Revert 129069 - Import libusb 1.0.9-rc3 into third_party.

Failing license check.

http://chromegw.corp.google.com/i/chromium/builders/Linux/builds/21702/steps/check_licenses


BUG=none
TEST=none

Review URL: http://codereview.chromium.org/9826025

TBR=gdk@chromium.org
Review URL: https://chromiumcodereview.appspot.com/9866021

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@129101 0039d316-1c4b-4281-b951-d872f2087c98

53 files changed, 0 insertions, 22047 deletions

diff --git a/third_party/libusb/AUTHORS b/third_party/libusb/AUTHORS
deleted file mode 100644
index 9ced4a9..0000000
--- a/third_party/libusb/AUTHORS
+++ /dev/null
@@ -1,24 +0,0 @@
-Copyright (C) 2007-2009 Daniel Drake <dsd@gentoo.org>
-Copyright (c) 2001 Johannes Erdfelt <johannes@erdfelt.com>
-Copyright (C) 2008-2010 Nathan Hjelm <hjelmn@users.sourceforge.net>
-Copyright (C) 2009-2010 Pete Batard <pbatard@gmail.com>
-Copyright (C) 2010 Michael Plante <michael.plante@gmail.com>
-
-Other contributors:
-Alex Vatchenko
-Artem Egorkine
-Aurelien Jarno
-Bastien Nocera
-David Engraf
-David Moore
-Felipe Balbi
-Hans Ulrich Niedermann
-Hoi-Ho Chan
-Ludovic Rousseau
-Martin Koegler
-Mikhail Gusarov
-Peter Stuge
-Rob Walker
-Toby Peterson
-Vasily Khoruzhick
-
diff --git a/third_party/libusb/COPYING b/third_party/libusb/COPYING
deleted file mode 100644
index 5ab7695..0000000
--- a/third_party/libusb/COPYING
+++ /dev/null
@@ -1,504 +0,0 @@
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diff --git a/third_party/libusb/INSTALL b/third_party/libusb/INSTALL
deleted file mode 100644
index 5458714..0000000
--- a/third_party/libusb/INSTALL
+++ /dev/null
@@ -1,234 +0,0 @@
-Installation Instructions
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-   The file `configure.ac' (or `configure.in') is used to create
-`configure' by a program called `autoconf'.  You need `configure.ac' if
-you want to change it or regenerate `configure' using a newer version
-of `autoconf'.
-
-The simplest way to compile this package is:
-
-  1. `cd' to the directory containing the package's source code and type
-     `./configure' to configure the package for your system.
-
-     Running `configure' might take a while.  While running, it prints
-     some messages telling which features it is checking for.
-
-  2. Type `make' to compile the package.
-
-  3. Optionally, type `make check' to run any self-tests that come with
-     the package.
-
-  4. Type `make install' to install the programs and any data files and
-     documentation.
-
-  5. You can remove the program binaries and object files from the
-     source code directory by typing `make clean'.  To also remove the
-     files that `configure' created (so you can compile the package for
-     a different kind of computer), type `make distclean'.  There is
-     also a `make maintainer-clean' target, but that is intended mainly
-     for the package's developers.  If you use it, you may have to get
-     all sorts of other programs in order to regenerate files that came
-     with the distribution.
-
-Compilers and Options
-=====================
-
-Some systems require unusual options for compilation or linking that the
-`configure' script does not know about.  Run `./configure --help' for
-details on some of the pertinent environment variables.
-
-   You can give `configure' initial values for configuration parameters
-by setting variables in the command line or in the environment.  Here
-is an example:
-
-     ./configure CC=c99 CFLAGS=-g LIBS=-lposix
-
-   *Note Defining Variables::, for more details.
-
-Compiling For Multiple Architectures
-====================================
-
-You can compile the package for more than one kind of computer at the
-same time, by placing the object files for each architecture in their
-own directory.  To do this, you can use GNU `make'.  `cd' to the
-directory where you want the object files and executables to go and run
-the `configure' script.  `configure' automatically checks for the
-source code in the directory that `configure' is in and in `..'.
-
-   With a non-GNU `make', it is safer to compile the package for one
-architecture at a time in the source code directory.  After you have
-installed the package for one architecture, use `make distclean' before
-reconfiguring for another architecture.
-
-Installation Names
-==================
-
-By default, `make install' installs the package's commands under
-`/usr/local/bin', include files under `/usr/local/include', etc.  You
-can specify an installation prefix other than `/usr/local' by giving
-`configure' the option `--prefix=PREFIX'.
-
-   You can specify separate installation prefixes for
-architecture-specific files and architecture-independent files.  If you
-pass the option `--exec-prefix=PREFIX' to `configure', the package uses
-PREFIX as the prefix for installing programs and libraries.
-Documentation and other data files still use the regular prefix.
-
-   In addition, if you use an unusual directory layout you can give
-options like `--bindir=DIR' to specify different values for particular
-kinds of files.  Run `configure --help' for a list of the directories
-you can set and what kinds of files go in them.
-
-   If the package supports it, you can cause programs to be installed
-with an extra prefix or suffix on their names by giving `configure' the
-option `--program-prefix=PREFIX' or `--program-suffix=SUFFIX'.
-
-Optional Features
-=================
-
-Some packages pay attention to `--enable-FEATURE' options to
-`configure', where FEATURE indicates an optional part of the package.
-They may also pay attention to `--with-PACKAGE' options, where PACKAGE
-is something like `gnu-as' or `x' (for the X Window System).  The
-`README' should mention any `--enable-' and `--with-' options that the
-package recognizes.
-
-   For packages that use the X Window System, `configure' can usually
-find the X include and library files automatically, but if it doesn't,
-you can use the `configure' options `--x-includes=DIR' and
-`--x-libraries=DIR' to specify their locations.
-
-Specifying the System Type
-==========================
-
-There may be some features `configure' cannot figure out automatically,
-but needs to determine by the type of machine the package will run on.
-Usually, assuming the package is built to be run on the _same_
-architectures, `configure' can figure that out, but if it prints a
-message saying it cannot guess the machine type, give it the
-`--build=TYPE' option.  TYPE can either be a short name for the system
-type, such as `sun4', or a canonical name which has the form:
-
-     CPU-COMPANY-SYSTEM
-
-where SYSTEM can have one of these forms:
-
-     OS KERNEL-OS
-
-   See the file `config.sub' for the possible values of each field.  If
-`config.sub' isn't included in this package, then this package doesn't
-need to know the machine type.
-
-   If you are _building_ compiler tools for cross-compiling, you should
-use the option `--target=TYPE' to select the type of system they will
-produce code for.
-
-   If you want to _use_ a cross compiler, that generates code for a
-platform different from the build platform, you should specify the
-"host" platform (i.e., that on which the generated programs will
-eventually be run) with `--host=TYPE'.
-
-Sharing Defaults
-================
-
-If you want to set default values for `configure' scripts to share, you
-can create a site shell script called `config.site' that gives default
-values for variables like `CC', `cache_file', and `prefix'.
-`configure' looks for `PREFIX/share/config.site' if it exists, then
-`PREFIX/etc/config.site' if it exists.  Or, you can set the
-`CONFIG_SITE' environment variable to the location of the site script.
-A warning: not all `configure' scripts look for a site script.
-
-Defining Variables
-==================
-
-Variables not defined in a site shell script can be set in the
-environment passed to `configure'.  However, some packages may run
-configure again during the build, and the customized values of these
-variables may be lost.  In order to avoid this problem, you should set
-them in the `configure' command line, using `VAR=value'.  For example:
-
-     ./configure CC=/usr/local2/bin/gcc
-
-causes the specified `gcc' to be used as the C compiler (unless it is
-overridden in the site shell script).
-
-Unfortunately, this technique does not work for `CONFIG_SHELL' due to
-an Autoconf bug.  Until the bug is fixed you can use this workaround:
-
-     CONFIG_SHELL=/bin/bash /bin/bash ./configure CONFIG_SHELL=/bin/bash
-
-`configure' Invocation
-======================
-
-`configure' recognizes the following options to control how it operates.
-
-`--help'
-`-h'
-     Print a summary of the options to `configure', and exit.
-
-`--version'
-`-V'
-     Print the version of Autoconf used to generate the `configure'
-     script, and exit.
-
-`--cache-file=FILE'
-     Enable the cache: use and save the results of the tests in FILE,
-     traditionally `config.cache'.  FILE defaults to `/dev/null' to
-     disable caching.
-
-`--config-cache'
-`-C'
-     Alias for `--cache-file=config.cache'.
-
-`--quiet'
-`--silent'
-`-q'
-     Do not print messages saying which checks are being made.  To
-     suppress all normal output, redirect it to `/dev/null' (any error
-     messages will still be shown).
-
-`--srcdir=DIR'
-     Look for the package's source code in directory DIR.  Usually
-     `configure' can determine that directory automatically.
-
-`configure' also accepts some other, not widely useful, options.  Run
-`configure --help' for more details.
-
diff --git a/third_party/libusb/Makefile.am b/third_party/libusb/Makefile.am
deleted file mode 100644
index f59b8c3..0000000
--- a/third_party/libusb/Makefile.am
+++ /dev/null
@@ -1,28 +0,0 @@
-AUTOMAKE_OPTIONS = dist-bzip2 no-dist-gzip
-ACLOCAL_AMFLAGS = -I m4
-DISTCLEANFILES = libusb-1.0.pc
-MAINTAINERCLEANFILES = ChangeLog
-EXTRA_DIST = TODO PORTING
-SUBDIRS = libusb doc
-
-if BUILD_EXAMPLES
-SUBDIRS += examples
-endif
-
-pkgconfigdir=$(libdir)/pkgconfig
-pkgconfig_DATA=libusb-1.0.pc
-
-.PHONY: ChangeLog dist-up
-ChangeLog:
-	git --git-dir $(top_srcdir)/.git log > ChangeLog || touch ChangeLog
-
-dist-hook: ChangeLog
-
-reldir = .release/$(distdir)
-dist-up: dist
-	rm -rf $(reldir)
-	mkdir -p $(reldir)
-	cp $(distdir).tar.bz2 $(reldir)
-	rsync -rv $(reldir) frs.sourceforge.net:/home/frs/project/l/li/libusb/libusb-1.0/
-	rm -rf $(reldir)
-
diff --git a/third_party/libusb/NEWS b/third_party/libusb/NEWS
deleted file mode 100644
index 42c232c..0000000
--- a/third_party/libusb/NEWS
+++ /dev/null
@@ -1,56 +0,0 @@
-This file lists notable changes in each release. For the full history of all
-changes, see ChangeLog.
-
-2010-05-07: v1.0.8
-* Bug fixes
-
-2010-04-19: v1.0.7
-* Bug fixes and documentation tweaks
-* Add more interface class definitions
-
-2009-11-22: v1.0.6
-* Bug fixes
-* Increase libusb_handle_events() timeout to 60s for powersaving
-
-2009-11-15: v1.0.5
- * Use timerfd when available for timer management
- * Small fixes/updates
-
-2009-11-06: v1.0.4 release
- * Bug fixes including transfer locking to fix some potential threading races
- * More flexibility with clock types on Linux
- * Use new bulk continuation tracking in Linux 2.6.32 for improved handling
-   of short/failed transfers
-
-2009-08-27: v1.0.3 release
- * Bug fixes
- * Add libusb_get_max_iso_packet_size()
-
-2009-06-13: v1.0.2 release
- * Bug fixes
-
-2009-05-12: v1.0.1 release
- * Bug fixes
- * Darwin backend
-
-2008-12-13: v1.0.0 release
- * Bug fixes
-
-2008-11-21: v0.9.4 release
- * Bug fixes
- * Add libusb_attach_kernel_driver()
-
-2008-08-23: v0.9.3 release
- * Bug fixes
-
-2008-07-19: v0.9.2 release
- * Bug fixes
-
-2008-06-28: v0.9.1 release
- * Bug fixes
- * Introduce contexts to the API
- * Compatibility with new Linux kernel features
-
-2008-05-25: v0.9.0 release
- * First libusb-1.0 beta release
-
diff --git a/third_party/libusb/PORTING b/third_party/libusb/PORTING
deleted file mode 100644
index 7070784..0000000
--- a/third_party/libusb/PORTING
+++ /dev/null
@@ -1,95 +0,0 @@
-PORTING LIBUSB TO OTHER PLATFORMS
-
-Introduction
-============
-
-This document is aimed at developers wishing to port libusb to unsupported
-platforms. I believe the libusb API is OS-independent, so by supporting
-multiple operating systems we pave the way for cross-platform USB device
-drivers.
-
-Implementation-wise, the basic idea is that you provide an interface to
-libusb's internal "backend" API, which performs the appropriate operations on
-your target platform.
-
-In terms of USB I/O, your backend provides functionality to submit
-asynchronous transfers (synchronous transfers are implemented in the higher
-layers, based on the async interface). Your backend must also provide
-functionality to cancel those transfers.
-
-Your backend must also provide an event handling function to "reap" ongoing
-transfers and process their results.
-
-The backend must also provide standard functions for other USB operations,
-e.g. setting configuration, obtaining descriptors, etc.
-
-
-File descriptors for I/O polling
-================================
-
-For libusb to work, your event handling function obviously needs to be called
-at various points in time. Your backend must provide a set of file descriptors
-which libusb and its users can pass to poll() or select() to determine when
-it is time to call the event handling function.
-
-On Linux, this is easy: the usbfs kernel interface exposes a file descriptor
-which can be passed to poll(). If something similar is not true for your
-platform, you can emulate this using an internal library thread to reap I/O as
-necessary, and a pipe() with the main library to raise events. The file
-descriptor of the pipe can then be provided to libusb as an event source.
-
-
-Interface semantics and documentation
-=====================================
-
-Documentation of the backend interface can be found in libusbi.h inside the
-usbi_os_backend structure definition.
-
-Your implementations of these functions will need to call various internal
-libusb functions, prefixed with "usbi_". Documentation for these functions
-can be found in the .c files where they are implemented.
-
-You probably want to skim over *all* the documentation before starting your
-implementation. For example, you probably need to allocate and store private
-OS-specific data for device handles, but the documentation for the mechanism
-for doing so is probably not the first thing you will see.
-
-The Linux backend acts as a good example - view it as a reference
-implementation which you should try to match the behaviour of.
-
-
-Getting started
-===============
-
-1. Modify configure.ac to detect your platform appropriately (see the OS_LINUX
-stuff for an example).
-
-2. Implement your backend in the libusb/os/ directory, modifying
-libusb/os/Makefile.am appropriately.
-
-3. Add preprocessor logic to the top of libusb/core.c to statically assign the
-right usbi_backend for your platform.
-
-4. Produce and test your implementation.
-
-5. Send your implementation to libusb-devel mailing list.
-
-
-Implementation difficulties? Questions?
-=======================================
-
-If you encounter difficulties porting libusb to your platform, please raise
-these issues on the libusb-devel mailing list. Where possible and sensible, I
-am interested in solving problems preventing libusb from operating on other
-platforms.
-
-The libusb-devel mailing list is also a good place to ask questions and
-make suggestions about the internal API. Hopefully we can produce some
-better documentation based on your questions and other input.
-
-You are encouraged to get involved in the process; if the library needs
-some infrastructure additions/modifications to better support your platform,
-you are encouraged to make such changes (in cleanly distinct patch
-submissions). Even if you do not make such changes yourself, please do raise
-the issues on the mailing list at the very minimum.
-
diff --git a/third_party/libusb/README b/third_party/libusb/README
deleted file mode 100644
index c5dabd7..0000000
--- a/third_party/libusb/README
+++ /dev/null
@@ -1,23 +0,0 @@
-libusb
-======
-
-libusb is a library for USB device access from Linux, Mac OS X and
-Windows userspace.
-It is written in C and licensed under the LGPL-2.1 (see COPYING).
-
-libusb is abstracted internally in such a way that it can hopefully
-be ported to other operating systems. See the PORTING file for some
-information, if you fancy a challenge :)
-
-libusb homepage:
-http://libusb.org/
-
-Developers will wish to consult the API documentation:
-http://libusb.sourceforge.net/api-1.0/
-
-Use the mailing list for questions, comments, etc:
-https://sourceforge.net/mailarchive/forum.php?forum_name=libusb-devel
-
-- Daniel Drake <dsd@gentoo.org>
-- Peter Stuge <peter@stuge.se>
-(use the mailing list rather than mailing developers directly)
diff --git a/third_party/libusb/README.chromium b/third_party/libusb/README.chromium
deleted file mode 100644
index df7680b..0000000
--- a/third_party/libusb/README.chromium
+++ /dev/null
@@ -1,12 +0,0 @@
-Name: libusb
-URL: http://libusb.org
-Version: 1.0.8
-License: LGPL 2.1
-Security Critical: yes
-
-Description:
-libusb provides a platform-agnostic API for accessing the USB subsystem on Mac,
-Windows, and Linux systems.
-
-Local Modifications:
-- config.h has been populated with required defines.
diff --git a/third_party/libusb/THANKS b/third_party/libusb/THANKS
deleted file mode 100644
index d926126..0000000
--- a/third_party/libusb/THANKS
+++ /dev/null
@@ -1,8 +0,0 @@
-Development contributors are listed in the AUTHORS file. Other community
-members who have made significant contributions in other areas are listed
-in this file:
-
-Alan Stern
-Ludovic Rousseau
-Tim Roberts
-Xiaofan Chen
diff --git a/third_party/libusb/TODO b/third_party/libusb/TODO
deleted file mode 100644
index 6c162a3..0000000
--- a/third_party/libusb/TODO
+++ /dev/null
@@ -1,9 +0,0 @@
-for 1.1 or future
-==================
-optional timerfd support (runtime detection)
-notifications of hotplugged/unplugged devices
-offer API to create/destroy handle_events thread
-isochronous sync I/O?
-exposing of parent-child device relationships
-"usb primer" introduction docs
-more examples
diff --git a/third_party/libusb/autogen.sh b/third_party/libusb/autogen.sh
deleted file mode 100755
index d5c6a19..0000000
--- a/third_party/libusb/autogen.sh
+++ /dev/null
@@ -1,12 +0,0 @@
-#!/bin/sh
-
-# use glibtoolize if it is available (darwin)
-(glibtoolize --version) < /dev/null > /dev/null 2>&1 && LIBTOOLIZE=glibtoolize || LIBTOOLIZE=libtoolize
-
-$LIBTOOLIZE --copy --force || exit 1
-aclocal || exit 1
-autoheader || exit 1
-autoconf || exit 1
-automake -a -c || exit 1
-./configure --enable-maintainer-mode --enable-debug-log \
-	--enable-examples-build $*
diff --git a/third_party/libusb/config.h b/third_party/libusb/config.h
deleted file mode 100644
index ac62ec9..0000000
--- a/third_party/libusb/config.h
+++ /dev/null
@@ -1,7 +0,0 @@
-#define DEFAULT_VISIBILITY
-#define _GNU_SOURCE 1
-
-// #define ENABLE_DEBUG_LOGGING 1
-// #define ENABLE_LOGGING 1
-
-// #define USBI_TIMERFD_AVAILABLE 1
diff --git a/third_party/libusb/configure.ac b/third_party/libusb/configure.ac
deleted file mode 100644
index 8020907..0000000
--- a/third_party/libusb/configure.ac
+++ /dev/null
@@ -1,198 +0,0 @@
-dnl These m4 macros are whitespace sensitive and break if moved around much.
-m4_define([LU_VERSION_H], m4_include([libusb/version.h]))
-m4_define([LU_DEFINE_VERSION_ATOM],
-	[m4_define([$1], m4_bregexp(LU_VERSION_H,
-	[^#define\s*$1\s*\([0-9]*\).*], [\1]))])
-m4_define([LU_DEFINE_VERSION_RC_ATOM],
-	[m4_define([$1], m4_bregexp(LU_VERSION_H,
-	[^#define\s*$1\s*"\(-rc[0-9]*\)".*], [\1]))])
-dnl The m4_bregexp() returns (only) the numbers following the #define named
-dnl in the first macro parameter. m4_define() then defines the name for use
-dnl in AC_INIT().
-
-LU_DEFINE_VERSION_ATOM([LIBUSB_MAJOR])
-LU_DEFINE_VERSION_ATOM([LIBUSB_MINOR])
-LU_DEFINE_VERSION_ATOM([LIBUSB_MICRO])
-LU_DEFINE_VERSION_RC_ATOM([LIBUSB_RC])
-
-AC_INIT([libusb], LIBUSB_MAJOR[.]LIBUSB_MINOR[.]LIBUSB_MICRO[]LIBUSB_RC, [libusb-devel@lists.sourceforge.net], [libusb], [http://www.libusb.org/])
-
-# Library versioning
-# These numbers should be tweaked on every release. Read carefully:
-# http://www.gnu.org/software/libtool/manual/html_node/Updating-version-info.html
-# http://sourceware.org/autobook/autobook/autobook_91.html
-lt_current="1"
-lt_revision="0"
-lt_age="1"
-LTLDFLAGS="-version-info ${lt_current}:${lt_revision}:${lt_age}"
-
-AM_INIT_AUTOMAKE
-AM_MAINTAINER_MODE
-
-AC_CONFIG_SRCDIR([libusb/core.c])
-AC_CONFIG_MACRO_DIR([m4])
-AM_CONFIG_HEADER([config.h])
-m4_ifdef([AM_SILENT_RULES],[AM_SILENT_RULES([yes])])
-
-AC_PREREQ([2.50])
-AC_PROG_CC
-AC_PROG_LIBTOOL
-AC_C_INLINE
-AM_PROG_CC_C_O
-AC_DEFINE([_GNU_SOURCE], 1, [Use GNU extensions])
-
-LTLDFLAGS="${LTLDFLAGS} -no-undefined"
-
-AC_MSG_CHECKING([operating system])
-case $host in
-*-linux*)
-	AC_DEFINE(OS_LINUX, 1, [Linux backend])
-	AC_SUBST(OS_LINUX)
-	AC_MSG_RESULT([Linux])
-	backend="linux"
-	AC_CHECK_LIB(rt, clock_gettime, PC_LIBS_PRIVATE="-lrt")
-	threads="posix"
-	THREAD_CFLAGS="-pthread"
-	PC_LIBS_PRIVATE="${PC_LIBS_PRIVATE} -pthread"
-	AC_CHECK_HEADERS([poll.h])
-	AC_DEFINE([POLL_NFDS_TYPE],[nfds_t],[type of second poll() argument])
-	;;
-*-darwin*)
-	AC_DEFINE(OS_DARWIN, 1, [Darwin backend])
-	AC_SUBST(OS_DARWIN)
-	AC_MSG_RESULT([Darwin/Mac OS X])
-	backend="darwin"
-	threads="posix"
-	LIBS="${LIBS} -lobjc"
-	PC_LIBS_PRIVATE="-Wl,-framework,IOKit -Wl,-framework,CoreFoundation"
-	LTLDFLAGS="${LTLDFLAGS} -Wl,-prebind"
-	AC_CHECK_HEADERS([poll.h])
-	AC_CHECK_TYPE([nfds_t],
-		[AC_DEFINE([POLL_NFDS_TYPE],[nfds_t],[type of second poll() argument])],
-		[AC_DEFINE([POLL_NFDS_TYPE],[unsigned int],[type of second poll() argument])],
-		[#include <poll.h>])
-	;;
-*-mingw*)
-	AC_MSG_RESULT([Windows])
-	backend="windows"
-	;;
-*-cygwin*)
-	AC_MSG_RESULT([Cygwin (using Windows backend)])
-	backend="windows"
-	threads="posix"
-	;;
-*)
-	AC_MSG_ERROR([unsupported operating system])
-esac
-if test "$backend" = windows; then
-	AC_DEFINE(OS_WINDOWS, 1, [Windows backend])
-	AC_SUBST(OS_WINDOWS)
-	PC_LIBS_PRIVATE=""
-	LTLDFLAGS="${LTLDFLAGS} -avoid-version -Wl,--add-stdcall-alias"
-	AC_CHECK_TOOL(RC, windres, no)
-	AC_DEFINE([POLL_NFDS_TYPE],[unsigned int],[type of second poll() argument])
-fi
-AC_SUBST(THREAD_CFLAGS)
-AC_SUBST(PC_LIBS_PRIVATE)
-LIBS="${LIBS} ${PC_LIBS_PRIVATE}"
-
-AM_CONDITIONAL(OS_LINUX, test "x$backend" = xlinux)
-AM_CONDITIONAL(OS_DARWIN, test "x$backend" = xdarwin)
-AM_CONDITIONAL(OS_WINDOWS, test "x$backend" = xwindows)
-AM_CONDITIONAL(THREADS_POSIX, test "x$threads" = xposix)
-if test "$threads" = posix; then
-	AC_DEFINE(THREADS_POSIX, 1, [Use POSIX Threads])
-fi
-
-# timerfd
-AC_CHECK_HEADER([sys/timerfd.h], [timerfd_h=1], [timerfd_h=0])
-AC_ARG_ENABLE([timerfd],
-	[AS_HELP_STRING([--enable-timerfd],
-		[use timerfd for timing (default auto)])],
-	[use_timerfd=$enableval], [use_timerfd='auto'])
-
-if test "x$use_timerfd" = "xyes" -a "x$timerfd_h" = "x0"; then
-	AC_MSG_ERROR([timerfd header not available; glibc 2.9+ required])
-fi
-
-AC_CHECK_DECL([TFD_NONBLOCK], [tfd_hdr_ok=yes], [tfd_hdr_ok=no], [#include <sys/timerfd.h>])
-if test "x$use_timerfd" = "xyes" -a "x$tfd_hdr_ok" = "xno"; then
-	AC_MSG_ERROR([timerfd header not usable; glibc 2.9+ required])
-fi
-
-AC_MSG_CHECKING([whether to use timerfd for timing])
-if test "x$use_timerfd" = "xno"; then
-	AC_MSG_RESULT([no (disabled by user)])
-else
-	if test "x$timerfd_h" = "x1" -a "x$tfd_hdr_ok" = "xyes"; then
-		AC_MSG_RESULT([yes])
-		AC_DEFINE(USBI_TIMERFD_AVAILABLE, 1, [timerfd headers available])
-	else
-		AC_MSG_RESULT([no (header not available)])
-	fi
-fi
-
-AC_CHECK_TYPES(struct timespec)
-
-# Message logging
-AC_ARG_ENABLE([log], [AS_HELP_STRING([--disable-log], [disable all logging])],
-	[log_enabled=$enableval],
-	[log_enabled='yes'])
-if test "x$log_enabled" != "xno"; then
-	AC_DEFINE([ENABLE_LOGGING], 1, [Message logging])
-fi
-
-AC_ARG_ENABLE([debug-log], [AS_HELP_STRING([--enable-debug-log],
-	[enable debug logging (default n)])],
-	[debug_log_enabled=$enableval],
-	[debug_log_enabled='no'])
-if test "x$debug_log_enabled" != "xno"; then
-	AC_DEFINE([ENABLE_DEBUG_LOGGING], 1, [Debug message logging])
-fi
-
-# Examples build
-AC_ARG_ENABLE([examples-build], [AS_HELP_STRING([--enable-examples-build],
-	[build example applications (default n)])],
-	[build_examples=$enableval],
-	[build_examples='no'])
-AM_CONDITIONAL([BUILD_EXAMPLES], [test "x$build_examples" != "xno"])
-
-# check for -fvisibility=hidden compiler support (GCC >= 3.4)
-saved_cflags="$CFLAGS"
-# -Werror required for cygwin
-CFLAGS="$CFLAGS -Werror -fvisibility=hidden"
-AC_COMPILE_IFELSE([AC_LANG_PROGRAM([])],
-	[VISIBILITY_CFLAGS="-fvisibility=hidden"
-	 AC_DEFINE([DEFAULT_VISIBILITY], [__attribute__((visibility("default")))], [Default visibility]) ],
-	[ VISIBILITY_CFLAGS=""
-	 AC_DEFINE([DEFAULT_VISIBILITY], [], [Default visibility]) ],
-	])
-CFLAGS="$saved_cflags"
-
-# check for -Wno-pointer-sign compiler support (GCC >= 4)
-saved_cflags="$CFLAGS"
-CFLAGS="$CFLAGS -Wno-pointer-sign"
-AC_COMPILE_IFELSE([AC_LANG_PROGRAM([])],
-	nopointersign_cflags="-Wno-pointer-sign", nopointersign_cflags="")
-CFLAGS="$saved_cflags"
-
-# sigaction not available on MinGW
-AC_CHECK_FUNC([sigaction], [have_sigaction=yes], [have_sigaction=no])
-AM_CONDITIONAL([HAVE_SIGACTION], [test "x$have_sigaction" = "xyes"])
-
-# headers not available on all platforms but required on others
-AC_CHECK_HEADERS([sys/time.h])
-
-AM_CFLAGS="-std=gnu99 -Wall -Wundef -Wunused -Wstrict-prototypes -Werror-implicit-function-declaration $nopointersign_cflags -Wshadow"
-
-AC_SUBST(VISIBILITY_CFLAGS)
-AC_SUBST(AM_CFLAGS)
-AC_SUBST(LTLDFLAGS)
-
-AC_CONFIG_FILES([libusb-1.0.pc])
-AC_CONFIG_FILES([Makefile])
-AC_CONFIG_FILES([libusb/Makefile])
-AC_CONFIG_FILES([examples/Makefile])
-AC_CONFIG_FILES([doc/Makefile])
-AC_CONFIG_FILES([doc/doxygen.cfg])
-AC_OUTPUT
diff --git a/third_party/libusb/doc/Makefile.am b/third_party/libusb/doc/Makefile.am
deleted file mode 100644
index ac5b189..0000000
--- a/third_party/libusb/doc/Makefile.am
+++ /dev/null
@@ -1,10 +0,0 @@
-EXTRA_DIST = doxygen.cfg.in
-
-docs: doxygen.cfg
-	doxygen $^
-
-docs-upload: docs
-	ln -s html api-1.0
-	rsync -av api-1.0/ dsd_,libusb@web.sourceforge.net:htdocs/api-1.0/
-	rm -f api-1.0
-
diff --git a/third_party/libusb/doc/doxygen.cfg.in b/third_party/libusb/doc/doxygen.cfg.in
deleted file mode 100644
index 128e1de..0000000
--- a/third_party/libusb/doc/doxygen.cfg.in
+++ /dev/null
@@ -1,1294 +0,0 @@
-# Doxyfile 1.5.3
-
-# This file describes the settings to be used by the documentation system
-# doxygen (www.doxygen.org) for a project
-#
-# All text after a hash (#) is considered a comment and will be ignored
-# The format is:
-#       TAG = value [value, ...]
-# For lists items can also be appended using:
-#       TAG += value [value, ...]
-# Values that contain spaces should be placed between quotes (" ")
-
-#---------------------------------------------------------------------------
-# Project related configuration options
-#---------------------------------------------------------------------------
-
-# This tag specifies the encoding used for all characters in the config file that 
-# follow. The default is UTF-8 which is also the encoding used for all text before 
-# the first occurrence of this tag. Doxygen uses libiconv (or the iconv built into 
-# libc) for the transcoding. See http://www.gnu.org/software/libiconv for the list of 
-# possible encodings.
-
-DOXYFILE_ENCODING      = UTF-8
-
-# The PROJECT_NAME tag is a single word (or a sequence of words surrounded 
-# by quotes) that should identify the project.
-
-PROJECT_NAME           = libusb
-
-# The PROJECT_NUMBER tag can be used to enter a project or revision number. 
-# This could be handy for archiving the generated documentation or 
-# if some version control system is used.
-
-PROJECT_NUMBER         = 
-
-# The OUTPUT_DIRECTORY tag is used to specify the (relative or absolute) 
-# base path where the generated documentation will be put. 
-# If a relative path is entered, it will be relative to the location 
-# where doxygen was started. If left blank the current directory will be used.
-
-OUTPUT_DIRECTORY       = 
-
-# If the CREATE_SUBDIRS tag is set to YES, then doxygen will create 
-# 4096 sub-directories (in 2 levels) under the output directory of each output 
-# format and will distribute the generated files over these directories. 
-# Enabling this option can be useful when feeding doxygen a huge amount of 
-# source files, where putting all generated files in the same directory would 
-# otherwise cause performance problems for the file system.
-
-CREATE_SUBDIRS         = NO
-
-# The OUTPUT_LANGUAGE tag is used to specify the language in which all 
-# documentation generated by doxygen is written. Doxygen will use this 
-# information to generate all constant output in the proper language. 
-# The default language is English, other supported languages are: 
-# Afrikaans, Arabic, Brazilian, Catalan, Chinese, Chinese-Traditional, 
-# Croatian, Czech, Danish, Dutch, Finnish, French, German, Greek, Hungarian, 
-# Italian, Japanese, Japanese-en (Japanese with English messages), Korean, 
-# Korean-en, Lithuanian, Norwegian, Polish, Portuguese, Romanian, Russian, 
-# Serbian, Slovak, Slovene, Spanish, Swedish, and Ukrainian.
-
-OUTPUT_LANGUAGE        = English
-
-# If the BRIEF_MEMBER_DESC tag is set to YES (the default) Doxygen will 
-# include brief member descriptions after the members that are listed in 
-# the file and class documentation (similar to JavaDoc). 
-# Set to NO to disable this.
-
-BRIEF_MEMBER_DESC      = YES
-
-# If the REPEAT_BRIEF tag is set to YES (the default) Doxygen will prepend 
-# the brief description of a member or function before the detailed description. 
-# Note: if both HIDE_UNDOC_MEMBERS and BRIEF_MEMBER_DESC are set to NO, the 
-# brief descriptions will be completely suppressed.
-
-REPEAT_BRIEF           = YES
-
-# This tag implements a quasi-intelligent brief description abbreviator 
-# that is used to form the text in various listings. Each string 
-# in this list, if found as the leading text of the brief description, will be 
-# stripped from the text and the result after processing the whole list, is 
-# used as the annotated text. Otherwise, the brief description is used as-is. 
-# If left blank, the following values are used ("$name" is automatically 
-# replaced with the name of the entity): "The $name class" "The $name widget" 
-# "The $name file" "is" "provides" "specifies" "contains" 
-# "represents" "a" "an" "the"
-
-ABBREVIATE_BRIEF       = 
-
-# If the ALWAYS_DETAILED_SEC and REPEAT_BRIEF tags are both set to YES then 
-# Doxygen will generate a detailed section even if there is only a brief 
-# description.
-
-ALWAYS_DETAILED_SEC    = NO
-
-# If the INLINE_INHERITED_MEMB tag is set to YES, doxygen will show all 
-# inherited members of a class in the documentation of that class as if those 
-# members were ordinary class members. Constructors, destructors and assignment 
-# operators of the base classes will not be shown.
-
-INLINE_INHERITED_MEMB  = NO
-
-# If the FULL_PATH_NAMES tag is set to YES then Doxygen will prepend the full 
-# path before files name in the file list and in the header files. If set 
-# to NO the shortest path that makes the file name unique will be used.
-
-FULL_PATH_NAMES        = NO
-
-# If the FULL_PATH_NAMES tag is set to YES then the STRIP_FROM_PATH tag 
-# can be used to strip a user-defined part of the path. Stripping is 
-# only done if one of the specified strings matches the left-hand part of 
-# the path. The tag can be used to show relative paths in the file list. 
-# If left blank the directory from which doxygen is run is used as the 
-# path to strip.
-
-STRIP_FROM_PATH        = 
-
-# The STRIP_FROM_INC_PATH tag can be used to strip a user-defined part of 
-# the path mentioned in the documentation of a class, which tells 
-# the reader which header file to include in order to use a class. 
-# If left blank only the name of the header file containing the class 
-# definition is used. Otherwise one should specify the include paths that 
-# are normally passed to the compiler using the -I flag.
-
-STRIP_FROM_INC_PATH    = 
-
-# If the SHORT_NAMES tag is set to YES, doxygen will generate much shorter 
-# (but less readable) file names. This can be useful is your file systems 
-# doesn't support long names like on DOS, Mac, or CD-ROM.
-
-SHORT_NAMES            = NO
-
-# If the JAVADOC_AUTOBRIEF tag is set to YES then Doxygen 
-# will interpret the first line (until the first dot) of a JavaDoc-style 
-# comment as the brief description. If set to NO, the JavaDoc 
-# comments will behave just like regular Qt-style comments 
-# (thus requiring an explicit @brief command for a brief description.)
-
-JAVADOC_AUTOBRIEF      = YES
-
-# If the QT_AUTOBRIEF tag is set to YES then Doxygen will 
-# interpret the first line (until the first dot) of a Qt-style 
-# comment as the brief description. If set to NO, the comments 
-# will behave just like regular Qt-style comments (thus requiring 
-# an explicit \brief command for a brief description.)
-
-QT_AUTOBRIEF           = NO
-
-# The MULTILINE_CPP_IS_BRIEF tag can be set to YES to make Doxygen 
-# treat a multi-line C++ special comment block (i.e. a block of //! or /// 
-# comments) as a brief description. This used to be the default behaviour. 
-# The new default is to treat a multi-line C++ comment block as a detailed 
-# description. Set this tag to YES if you prefer the old behaviour instead.
-
-MULTILINE_CPP_IS_BRIEF = NO
-
-# If the DETAILS_AT_TOP tag is set to YES then Doxygen 
-# will output the detailed description near the top, like JavaDoc.
-# If set to NO, the detailed description appears after the member 
-# documentation.
-
-DETAILS_AT_TOP         = NO
-
-# If the INHERIT_DOCS tag is set to YES (the default) then an undocumented 
-# member inherits the documentation from any documented member that it 
-# re-implements.
-
-INHERIT_DOCS           = YES
-
-# If the SEPARATE_MEMBER_PAGES tag is set to YES, then doxygen will produce 
-# a new page for each member. If set to NO, the documentation of a member will 
-# be part of the file/class/namespace that contains it.
-
-SEPARATE_MEMBER_PAGES  = NO
-
-# The TAB_SIZE tag can be used to set the number of spaces in a tab. 
-# Doxygen uses this value to replace tabs by spaces in code fragments.
-
-TAB_SIZE               = 4
-
-# This tag can be used to specify a number of aliases that acts 
-# as commands in the documentation. An alias has the form "name=value". 
-# For example adding "sideeffect=\par Side Effects:\n" will allow you to 
-# put the command \sideeffect (or @sideeffect) in the documentation, which 
-# will result in a user-defined paragraph with heading "Side Effects:". 
-# You can put \n's in the value part of an alias to insert newlines.
-
-ALIASES                = 
-
-# Set the OPTIMIZE_OUTPUT_FOR_C tag to YES if your project consists of C 
-# sources only. Doxygen will then generate output that is more tailored for C. 
-# For instance, some of the names that are used will be different. The list 
-# of all members will be omitted, etc.
-
-OPTIMIZE_OUTPUT_FOR_C  = YES
-
-# Set the OPTIMIZE_OUTPUT_JAVA tag to YES if your project consists of Java 
-# sources only. Doxygen will then generate output that is more tailored for Java. 
-# For instance, namespaces will be presented as packages, qualified scopes 
-# will look different, etc.
-
-OPTIMIZE_OUTPUT_JAVA   = NO
-
-# If you use STL classes (i.e. std::string, std::vector, etc.) but do not want to 
-# include (a tag file for) the STL sources as input, then you should 
-# set this tag to YES in order to let doxygen match functions declarations and 
-# definitions whose arguments contain STL classes (e.g. func(std::string); v.s. 
-# func(std::string) {}). This also make the inheritance and collaboration 
-# diagrams that involve STL classes more complete and accurate.
-
-BUILTIN_STL_SUPPORT    = NO
-
-# If you use Microsoft's C++/CLI language, you should set this option to YES to
-# enable parsing support.
-
-CPP_CLI_SUPPORT        = NO
-
-# If member grouping is used in the documentation and the DISTRIBUTE_GROUP_DOC 
-# tag is set to YES, then doxygen will reuse the documentation of the first 
-# member in the group (if any) for the other members of the group. By default 
-# all members of a group must be documented explicitly.
-
-DISTRIBUTE_GROUP_DOC   = NO
-
-# Set the SUBGROUPING tag to YES (the default) to allow class member groups of 
-# the same type (for instance a group of public functions) to be put as a 
-# subgroup of that type (e.g. under the Public Functions section). Set it to 
-# NO to prevent subgrouping. Alternatively, this can be done per class using 
-# the \nosubgrouping command.
-
-SUBGROUPING            = YES
-
-#---------------------------------------------------------------------------
-# Build related configuration options
-#---------------------------------------------------------------------------
-
-# If the EXTRACT_ALL tag is set to YES doxygen will assume all entities in 
-# documentation are documented, even if no documentation was available. 
-# Private class members and static file members will be hidden unless 
-# the EXTRACT_PRIVATE and EXTRACT_STATIC tags are set to YES
-
-EXTRACT_ALL            = NO
-
-# If the EXTRACT_PRIVATE tag is set to YES all private members of a class 
-# will be included in the documentation.
-
-EXTRACT_PRIVATE        = NO
-
-# If the EXTRACT_STATIC tag is set to YES all static members of a file 
-# will be included in the documentation.
-
-EXTRACT_STATIC         = YES
-
-# If the EXTRACT_LOCAL_CLASSES tag is set to YES classes (and structs) 
-# defined locally in source files will be included in the documentation. 
-# If set to NO only classes defined in header files are included.
-
-EXTRACT_LOCAL_CLASSES  = YES
-
-# This flag is only useful for Objective-C code. When set to YES local 
-# methods, which are defined in the implementation section but not in 
-# the interface are included in the documentation. 
-# If set to NO (the default) only methods in the interface are included.
-
-EXTRACT_LOCAL_METHODS  = NO
-
-# If this flag is set to YES, the members of anonymous namespaces will be extracted 
-# and appear in the documentation as a namespace called 'anonymous_namespace{file}', 
-# where file will be replaced with the base name of the file that contains the anonymous 
-# namespace. By default anonymous namespace are hidden.
-
-EXTRACT_ANON_NSPACES   = NO
-
-# If the HIDE_UNDOC_MEMBERS tag is set to YES, Doxygen will hide all 
-# undocumented members of documented classes, files or namespaces. 
-# If set to NO (the default) these members will be included in the 
-# various overviews, but no documentation section is generated. 
-# This option has no effect if EXTRACT_ALL is enabled.
-
-HIDE_UNDOC_MEMBERS     = NO
-
-# If the HIDE_UNDOC_CLASSES tag is set to YES, Doxygen will hide all 
-# undocumented classes that are normally visible in the class hierarchy. 
-# If set to NO (the default) these classes will be included in the various 
-# overviews. This option has no effect if EXTRACT_ALL is enabled.
-
-HIDE_UNDOC_CLASSES     = NO
-
-# If the HIDE_FRIEND_COMPOUNDS tag is set to YES, Doxygen will hide all 
-# friend (class|struct|union) declarations. 
-# If set to NO (the default) these declarations will be included in the 
-# documentation.
-
-HIDE_FRIEND_COMPOUNDS  = NO
-
-# If the HIDE_IN_BODY_DOCS tag is set to YES, Doxygen will hide any 
-# documentation blocks found inside the body of a function. 
-# If set to NO (the default) these blocks will be appended to the 
-# function's detailed documentation block.
-
-HIDE_IN_BODY_DOCS      = NO
-
-# The INTERNAL_DOCS tag determines if documentation 
-# that is typed after a \internal command is included. If the tag is set 
-# to NO (the default) then the documentation will be excluded. 
-# Set it to YES to include the internal documentation.
-
-INTERNAL_DOCS          = NO
-
-# If the CASE_SENSE_NAMES tag is set to NO then Doxygen will only generate 
-# file names in lower-case letters. If set to YES upper-case letters are also 
-# allowed. This is useful if you have classes or files whose names only differ 
-# in case and if your file system supports case sensitive file names. Windows 
-# and Mac users are advised to set this option to NO.
-
-CASE_SENSE_NAMES       = YES
-
-# If the HIDE_SCOPE_NAMES tag is set to NO (the default) then Doxygen 
-# will show members with their full class and namespace scopes in the 
-# documentation. If set to YES the scope will be hidden.
-
-HIDE_SCOPE_NAMES       = NO
-
-# If the SHOW_INCLUDE_FILES tag is set to YES (the default) then Doxygen 
-# will put a list of the files that are included by a file in the documentation 
-# of that file.
-
-SHOW_INCLUDE_FILES     = YES
-
-# If the INLINE_INFO tag is set to YES (the default) then a tag [inline] 
-# is inserted in the documentation for inline members.
-
-INLINE_INFO            = YES
-
-# If the SORT_MEMBER_DOCS tag is set to YES (the default) then doxygen 
-# will sort the (detailed) documentation of file and class members 
-# alphabetically by member name. If set to NO the members will appear in 
-# declaration order.
-
-SORT_MEMBER_DOCS       = NO
-
-# If the SORT_BRIEF_DOCS tag is set to YES then doxygen will sort the 
-# brief documentation of file, namespace and class members alphabetically 
-# by member name. If set to NO (the default) the members will appear in 
-# declaration order.
-
-SORT_BRIEF_DOCS        = NO
-
-# If the SORT_BY_SCOPE_NAME tag is set to YES, the class list will be 
-# sorted by fully-qualified names, including namespaces. If set to 
-# NO (the default), the class list will be sorted only by class name, 
-# not including the namespace part. 
-# Note: This option is not very useful if HIDE_SCOPE_NAMES is set to YES.
-# Note: This option applies only to the class list, not to the 
-# alphabetical list.
-
-SORT_BY_SCOPE_NAME     = NO
-
-# The GENERATE_TODOLIST tag can be used to enable (YES) or 
-# disable (NO) the todo list. This list is created by putting \todo 
-# commands in the documentation.
-
-GENERATE_TODOLIST      = YES
-
-# The GENERATE_TESTLIST tag can be used to enable (YES) or 
-# disable (NO) the test list. This list is created by putting \test 
-# commands in the documentation.
-
-GENERATE_TESTLIST      = YES
-
-# The GENERATE_BUGLIST tag can be used to enable (YES) or 
-# disable (NO) the bug list. This list is created by putting \bug 
-# commands in the documentation.
-
-GENERATE_BUGLIST       = YES
-
-# The GENERATE_DEPRECATEDLIST tag can be used to enable (YES) or 
-# disable (NO) the deprecated list. This list is created by putting 
-# \deprecated commands in the documentation.
-
-GENERATE_DEPRECATEDLIST= YES
-
-# The ENABLED_SECTIONS tag can be used to enable conditional 
-# documentation sections, marked by \if sectionname ... \endif.
-
-ENABLED_SECTIONS       = 
-
-# The MAX_INITIALIZER_LINES tag determines the maximum number of lines 
-# the initial value of a variable or define consists of for it to appear in 
-# the documentation. If the initializer consists of more lines than specified 
-# here it will be hidden. Use a value of 0 to hide initializers completely. 
-# The appearance of the initializer of individual variables and defines in the 
-# documentation can be controlled using \showinitializer or \hideinitializer 
-# command in the documentation regardless of this setting.
-
-MAX_INITIALIZER_LINES  = 30
-
-# Set the SHOW_USED_FILES tag to NO to disable the list of files generated 
-# at the bottom of the documentation of classes and structs. If set to YES the 
-# list will mention the files that were used to generate the documentation.
-
-SHOW_USED_FILES        = YES
-
-# If the sources in your project are distributed over multiple directories 
-# then setting the SHOW_DIRECTORIES tag to YES will show the directory hierarchy 
-# in the documentation. The default is NO.
-
-SHOW_DIRECTORIES       = NO
-
-# The FILE_VERSION_FILTER tag can be used to specify a program or script that 
-# doxygen should invoke to get the current version for each file (typically from the 
-# version control system). Doxygen will invoke the program by executing (via 
-# popen()) the command <command> <input-file>, where <command> is the value of 
-# the FILE_VERSION_FILTER tag, and <input-file> is the name of an input file 
-# provided by doxygen. Whatever the program writes to standard output 
-# is used as the file version. See the manual for examples.
-
-FILE_VERSION_FILTER    = 
-
-#---------------------------------------------------------------------------
-# configuration options related to warning and progress messages
-#---------------------------------------------------------------------------
-
-# The QUIET tag can be used to turn on/off the messages that are generated 
-# by doxygen. Possible values are YES and NO. If left blank NO is used.
-
-QUIET                  = NO
-
-# The WARNINGS tag can be used to turn on/off the warning messages that are 
-# generated by doxygen. Possible values are YES and NO. If left blank 
-# NO is used.
-
-WARNINGS               = YES
-
-# If WARN_IF_UNDOCUMENTED is set to YES, then doxygen will generate warnings 
-# for undocumented members. If EXTRACT_ALL is set to YES then this flag will 
-# automatically be disabled.
-
-WARN_IF_UNDOCUMENTED   = YES
-
-# If WARN_IF_DOC_ERROR is set to YES, doxygen will generate warnings for 
-# potential errors in the documentation, such as not documenting some 
-# parameters in a documented function, or documenting parameters that 
-# don't exist or using markup commands wrongly.
-
-WARN_IF_DOC_ERROR      = YES
-
-# This WARN_NO_PARAMDOC option can be abled to get warnings for 
-# functions that are documented, but have no documentation for their parameters 
-# or return value. If set to NO (the default) doxygen will only warn about 
-# wrong or incomplete parameter documentation, but not about the absence of 
-# documentation.
-
-WARN_NO_PARAMDOC       = NO
-
-# The WARN_FORMAT tag determines the format of the warning messages that 
-# doxygen can produce. The string should contain the $file, $line, and $text 
-# tags, which will be replaced by the file and line number from which the 
-# warning originated and the warning text. Optionally the format may contain 
-# $version, which will be replaced by the version of the file (if it could 
-# be obtained via FILE_VERSION_FILTER)
-
-WARN_FORMAT            = "$file:$line: $text"
-
-# The WARN_LOGFILE tag can be used to specify a file to which warning 
-# and error messages should be written. If left blank the output is written 
-# to stderr.
-
-WARN_LOGFILE           = 
-
-#---------------------------------------------------------------------------
-# configuration options related to the input files
-#---------------------------------------------------------------------------
-
-# The INPUT tag can be used to specify the files and/or directories that contain 
-# documented source files. You may enter file names like "myfile.cpp" or 
-# directories like "/usr/src/myproject". Separate the files or directories 
-# with spaces.
-
-INPUT                  = @top_srcdir@/libusb
-
-# This tag can be used to specify the character encoding of the source files that 
-# doxygen parses. Internally doxygen uses the UTF-8 encoding, which is also the default 
-# input encoding. Doxygen uses libiconv (or the iconv built into libc) for the transcoding. 
-# See http://www.gnu.org/software/libiconv for the list of possible encodings.
-
-INPUT_ENCODING         = UTF-8
-
-# If the value of the INPUT tag contains directories, you can use the 
-# FILE_PATTERNS tag to specify one or more wildcard pattern (like *.cpp 
-# and *.h) to filter out the source-files in the directories. If left 
-# blank the following patterns are tested: 
-# *.c *.cc *.cxx *.cpp *.c++ *.java *.ii *.ixx *.ipp *.i++ *.inl *.h *.hh *.hxx 
-# *.hpp *.h++ *.idl *.odl *.cs *.php *.php3 *.inc *.m *.mm *.py
-
-FILE_PATTERNS          = 
-
-# The RECURSIVE tag can be used to turn specify whether or not subdirectories 
-# should be searched for input files as well. Possible values are YES and NO. 
-# If left blank NO is used.
-
-RECURSIVE              = NO
-
-# The EXCLUDE tag can be used to specify files and/or directories that should 
-# excluded from the INPUT source files. This way you can easily exclude a 
-# subdirectory from a directory tree whose root is specified with the INPUT tag.
-
-EXCLUDE                = @top_srcdir@/libusb/libusbi.h
-
-# The EXCLUDE_SYMLINKS tag can be used select whether or not files or 
-# directories that are symbolic links (a Unix filesystem feature) are excluded 
-# from the input.
-
-EXCLUDE_SYMLINKS       = NO
-
-# If the value of the INPUT tag contains directories, you can use the 
-# EXCLUDE_PATTERNS tag to specify one or more wildcard patterns to exclude 
-# certain files from those directories. Note that the wildcards are matched 
-# against the file with absolute path, so to exclude all test directories 
-# for example use the pattern */test/*
-
-EXCLUDE_PATTERNS       = 
-
-# The EXCLUDE_SYMBOLS tag can be used to specify one or more symbol names 
-# (namespaces, classes, functions, etc.) that should be excluded from the output. 
-# The symbol name can be a fully qualified name, a word, or if the wildcard * is used, 
-# a substring. Examples: ANamespace, AClass, AClass::ANamespace, ANamespace::*Test
-
-EXCLUDE_SYMBOLS        = 
-
-# The EXAMPLE_PATH tag can be used to specify one or more files or 
-# directories that contain example code fragments that are included (see 
-# the \include command).
-
-EXAMPLE_PATH           = 
-
-# If the value of the EXAMPLE_PATH tag contains directories, you can use the 
-# EXAMPLE_PATTERNS tag to specify one or more wildcard pattern (like *.cpp 
-# and *.h) to filter out the source-files in the directories. If left 
-# blank all files are included.
-
-EXAMPLE_PATTERNS       = 
-
-# If the EXAMPLE_RECURSIVE tag is set to YES then subdirectories will be 
-# searched for input files to be used with the \include or \dontinclude 
-# commands irrespective of the value of the RECURSIVE tag. 
-# Possible values are YES and NO. If left blank NO is used.
-
-EXAMPLE_RECURSIVE      = NO
-
-# The IMAGE_PATH tag can be used to specify one or more files or 
-# directories that contain image that are included in the documentation (see 
-# the \image command).
-
-IMAGE_PATH             = 
-
-# The INPUT_FILTER tag can be used to specify a program that doxygen should 
-# invoke to filter for each input file. Doxygen will invoke the filter program 
-# by executing (via popen()) the command <filter> <input-file>, where <filter> 
-# is the value of the INPUT_FILTER tag, and <input-file> is the name of an 
-# input file. Doxygen will then use the output that the filter program writes 
-# to standard output.  If FILTER_PATTERNS is specified, this tag will be 
-# ignored.
-
-INPUT_FILTER           = 
-
-# The FILTER_PATTERNS tag can be used to specify filters on a per file pattern 
-# basis.  Doxygen will compare the file name with each pattern and apply the 
-# filter if there is a match.  The filters are a list of the form: 
-# pattern=filter (like *.cpp=my_cpp_filter). See INPUT_FILTER for further 
-# info on how filters are used. If FILTER_PATTERNS is empty, INPUT_FILTER 
-# is applied to all files.
-
-FILTER_PATTERNS        = 
-
-# If the FILTER_SOURCE_FILES tag is set to YES, the input filter (if set using 
-# INPUT_FILTER) will be used to filter the input files when producing source 
-# files to browse (i.e. when SOURCE_BROWSER is set to YES).
-
-FILTER_SOURCE_FILES    = NO
-
-#---------------------------------------------------------------------------
-# configuration options related to source browsing
-#---------------------------------------------------------------------------
-
-# If the SOURCE_BROWSER tag is set to YES then a list of source files will 
-# be generated. Documented entities will be cross-referenced with these sources. 
-# Note: To get rid of all source code in the generated output, make sure also 
-# VERBATIM_HEADERS is set to NO. If you have enabled CALL_GRAPH or CALLER_GRAPH 
-# then you must also enable this option. If you don't then doxygen will produce 
-# a warning and turn it on anyway
-
-SOURCE_BROWSER         = NO
-
-# Setting the INLINE_SOURCES tag to YES will include the body 
-# of functions and classes directly in the documentation.
-
-INLINE_SOURCES         = NO
-
-# Setting the STRIP_CODE_COMMENTS tag to YES (the default) will instruct 
-# doxygen to hide any special comment blocks from generated source code 
-# fragments. Normal C and C++ comments will always remain visible.
-
-STRIP_CODE_COMMENTS    = YES
-
-# If the REFERENCED_BY_RELATION tag is set to YES (the default) 
-# then for each documented function all documented 
-# functions referencing it will be listed.
-
-REFERENCED_BY_RELATION = NO
-
-# If the REFERENCES_RELATION tag is set to YES (the default) 
-# then for each documented function all documented entities 
-# called/used by that function will be listed.
-
-REFERENCES_RELATION    = NO
-
-# If the REFERENCES_LINK_SOURCE tag is set to YES (the default)
-# and SOURCE_BROWSER tag is set to YES, then the hyperlinks from
-# functions in REFERENCES_RELATION and REFERENCED_BY_RELATION lists will
-# link to the source code.  Otherwise they will link to the documentstion.
-
-REFERENCES_LINK_SOURCE = YES
-
-# If the USE_HTAGS tag is set to YES then the references to source code 
-# will point to the HTML generated by the htags(1) tool instead of doxygen 
-# built-in source browser. The htags tool is part of GNU's global source 
-# tagging system (see http://www.gnu.org/software/global/global.html). You 
-# will need version 4.8.6 or higher.
-
-USE_HTAGS              = NO
-
-# If the VERBATIM_HEADERS tag is set to YES (the default) then Doxygen 
-# will generate a verbatim copy of the header file for each class for 
-# which an include is specified. Set to NO to disable this.
-
-VERBATIM_HEADERS       = YES
-
-#---------------------------------------------------------------------------
-# configuration options related to the alphabetical class index
-#---------------------------------------------------------------------------
-
-# If the ALPHABETICAL_INDEX tag is set to YES, an alphabetical index 
-# of all compounds will be generated. Enable this if the project 
-# contains a lot of classes, structs, unions or interfaces.
-
-ALPHABETICAL_INDEX     = YES
-
-# If the alphabetical index is enabled (see ALPHABETICAL_INDEX) then 
-# the COLS_IN_ALPHA_INDEX tag can be used to specify the number of columns 
-# in which this list will be split (can be a number in the range [1..20])
-
-COLS_IN_ALPHA_INDEX    = 5
-
-# In case all classes in a project start with a common prefix, all 
-# classes will be put under the same header in the alphabetical index. 
-# The IGNORE_PREFIX tag can be used to specify one or more prefixes that 
-# should be ignored while generating the index headers.
-
-IGNORE_PREFIX          = 
-
-#---------------------------------------------------------------------------
-# configuration options related to the HTML output
-#---------------------------------------------------------------------------
-
-# If the GENERATE_HTML tag is set to YES (the default) Doxygen will 
-# generate HTML output.
-
-GENERATE_HTML          = YES
-
-# The HTML_OUTPUT tag is used to specify where the HTML docs will be put. 
-# If a relative path is entered the value of OUTPUT_DIRECTORY will be 
-# put in front of it. If left blank `html' will be used as the default path.
-
-HTML_OUTPUT            = html
-
-# The HTML_FILE_EXTENSION tag can be used to specify the file extension for 
-# each generated HTML page (for example: .htm,.php,.asp). If it is left blank 
-# doxygen will generate files with .html extension.
-
-HTML_FILE_EXTENSION    = .html
-
-# The HTML_HEADER tag can be used to specify a personal HTML header for 
-# each generated HTML page. If it is left blank doxygen will generate a 
-# standard header.
-
-HTML_HEADER            = 
-
-# The HTML_FOOTER tag can be used to specify a personal HTML footer for 
-# each generated HTML page. If it is left blank doxygen will generate a 
-# standard footer.
-
-HTML_FOOTER            = 
-
-# The HTML_STYLESHEET tag can be used to specify a user-defined cascading 
-# style sheet that is used by each HTML page. It can be used to 
-# fine-tune the look of the HTML output. If the tag is left blank doxygen 
-# will generate a default style sheet. Note that doxygen will try to copy 
-# the style sheet file to the HTML output directory, so don't put your own 
-# stylesheet in the HTML output directory as well, or it will be erased!
-
-HTML_STYLESHEET        = 
-
-# If the HTML_ALIGN_MEMBERS tag is set to YES, the members of classes, 
-# files or namespaces will be aligned in HTML using tables. If set to 
-# NO a bullet list will be used.
-
-HTML_ALIGN_MEMBERS     = YES
-
-# If the GENERATE_HTMLHELP tag is set to YES, additional index files 
-# will be generated that can be used as input for tools like the 
-# Microsoft HTML help workshop to generate a compressed HTML help file (.chm) 
-# of the generated HTML documentation.
-
-GENERATE_HTMLHELP      = NO
-
-# If the HTML_DYNAMIC_SECTIONS tag is set to YES then the generated HTML 
-# documentation will contain sections that can be hidden and shown after the 
-# page has loaded. For this to work a browser that supports 
-# JavaScript and DHTML is required (for instance Mozilla 1.0+, Firefox 
-# Netscape 6.0+, Internet explorer 5.0+, Konqueror, or Safari).
-
-HTML_DYNAMIC_SECTIONS  = YES
-
-# If the GENERATE_HTMLHELP tag is set to YES, the CHM_FILE tag can 
-# be used to specify the file name of the resulting .chm file. You 
-# can add a path in front of the file if the result should not be 
-# written to the html output directory.
-
-CHM_FILE               = 
-
-# If the GENERATE_HTMLHELP tag is set to YES, the HHC_LOCATION tag can 
-# be used to specify the location (absolute path including file name) of 
-# the HTML help compiler (hhc.exe). If non-empty doxygen will try to run 
-# the HTML help compiler on the generated index.hhp.
-
-HHC_LOCATION           = 
-
-# If the GENERATE_HTMLHELP tag is set to YES, the GENERATE_CHI flag 
-# controls if a separate .chi index file is generated (YES) or that 
-# it should be included in the master .chm file (NO).
-
-GENERATE_CHI           = NO
-
-# If the GENERATE_HTMLHELP tag is set to YES, the BINARY_TOC flag 
-# controls whether a binary table of contents is generated (YES) or a 
-# normal table of contents (NO) in the .chm file.
-
-BINARY_TOC             = NO
-
-# The TOC_EXPAND flag can be set to YES to add extra items for group members 
-# to the contents of the HTML help documentation and to the tree view.
-
-TOC_EXPAND             = NO
-
-# The DISABLE_INDEX tag can be used to turn on/off the condensed index at 
-# top of each HTML page. The value NO (the default) enables the index and 
-# the value YES disables it.
-
-DISABLE_INDEX          = NO
-
-# This tag can be used to set the number of enum values (range [1..20]) 
-# that doxygen will group on one line in the generated HTML documentation.
-
-ENUM_VALUES_PER_LINE   = 4
-
-# If the GENERATE_TREEVIEW tag is set to YES, a side panel will be
-# generated containing a tree-like index structure (just like the one that 
-# is generated for HTML Help). For this to work a browser that supports 
-# JavaScript, DHTML, CSS and frames is required (for instance Mozilla 1.0+, 
-# Netscape 6.0+, Internet explorer 5.0+, or Konqueror). Windows users are 
-# probably better off using the HTML help feature.
-
-GENERATE_TREEVIEW      = NO
-
-# If the treeview is enabled (see GENERATE_TREEVIEW) then this tag can be 
-# used to set the initial width (in pixels) of the frame in which the tree 
-# is shown.
-
-TREEVIEW_WIDTH         = 250
-
-#---------------------------------------------------------------------------
-# configuration options related to the LaTeX output
-#---------------------------------------------------------------------------
-
-# If the GENERATE_LATEX tag is set to YES (the default) Doxygen will 
-# generate Latex output.
-
-GENERATE_LATEX         = NO
-
-# The LATEX_OUTPUT tag is used to specify where the LaTeX docs will be put. 
-# If a relative path is entered the value of OUTPUT_DIRECTORY will be 
-# put in front of it. If left blank `latex' will be used as the default path.
-
-LATEX_OUTPUT           = latex
-
-# The LATEX_CMD_NAME tag can be used to specify the LaTeX command name to be 
-# invoked. If left blank `latex' will be used as the default command name.
-
-LATEX_CMD_NAME         = latex
-
-# The MAKEINDEX_CMD_NAME tag can be used to specify the command name to 
-# generate index for LaTeX. If left blank `makeindex' will be used as the 
-# default command name.
-
-MAKEINDEX_CMD_NAME     = makeindex
-
-# If the COMPACT_LATEX tag is set to YES Doxygen generates more compact 
-# LaTeX documents. This may be useful for small projects and may help to 
-# save some trees in general.
-
-COMPACT_LATEX          = NO
-
-# The PAPER_TYPE tag can be used to set the paper type that is used 
-# by the printer. Possible values are: a4, a4wide, letter, legal and 
-# executive. If left blank a4wide will be used.
-
-PAPER_TYPE             = a4wide
-
-# The EXTRA_PACKAGES tag can be to specify one or more names of LaTeX 
-# packages that should be included in the LaTeX output.
-
-EXTRA_PACKAGES         = 
-
-# The LATEX_HEADER tag can be used to specify a personal LaTeX header for 
-# the generated latex document. The header should contain everything until 
-# the first chapter. If it is left blank doxygen will generate a 
-# standard header. Notice: only use this tag if you know what you are doing!
-
-LATEX_HEADER           = 
-
-# If the PDF_HYPERLINKS tag is set to YES, the LaTeX that is generated 
-# is prepared for conversion to pdf (using ps2pdf). The pdf file will 
-# contain links (just like the HTML output) instead of page references 
-# This makes the output suitable for online browsing using a pdf viewer.
-
-PDF_HYPERLINKS         = NO
-
-# If the USE_PDFLATEX tag is set to YES, pdflatex will be used instead of 
-# plain latex in the generated Makefile. Set this option to YES to get a 
-# higher quality PDF documentation.
-
-USE_PDFLATEX           = NO
-
-# If the LATEX_BATCHMODE tag is set to YES, doxygen will add the \\batchmode. 
-# command to the generated LaTeX files. This will instruct LaTeX to keep 
-# running if errors occur, instead of asking the user for help. 
-# This option is also used when generating formulas in HTML.
-
-LATEX_BATCHMODE        = NO
-
-# If LATEX_HIDE_INDICES is set to YES then doxygen will not 
-# include the index chapters (such as File Index, Compound Index, etc.) 
-# in the output.
-
-LATEX_HIDE_INDICES     = NO
-
-#---------------------------------------------------------------------------
-# configuration options related to the RTF output
-#---------------------------------------------------------------------------
-
-# If the GENERATE_RTF tag is set to YES Doxygen will generate RTF output 
-# The RTF output is optimized for Word 97 and may not look very pretty with 
-# other RTF readers or editors.
-
-GENERATE_RTF           = NO
-
-# The RTF_OUTPUT tag is used to specify where the RTF docs will be put. 
-# If a relative path is entered the value of OUTPUT_DIRECTORY will be 
-# put in front of it. If left blank `rtf' will be used as the default path.
-
-RTF_OUTPUT             = rtf
-
-# If the COMPACT_RTF tag is set to YES Doxygen generates more compact 
-# RTF documents. This may be useful for small projects and may help to 
-# save some trees in general.
-
-COMPACT_RTF            = NO
-
-# If the RTF_HYPERLINKS tag is set to YES, the RTF that is generated 
-# will contain hyperlink fields. The RTF file will 
-# contain links (just like the HTML output) instead of page references. 
-# This makes the output suitable for online browsing using WORD or other 
-# programs which support those fields. 
-# Note: wordpad (write) and others do not support links.
-
-RTF_HYPERLINKS         = NO
-
-# Load stylesheet definitions from file. Syntax is similar to doxygen's 
-# config file, i.e. a series of assignments. You only have to provide 
-# replacements, missing definitions are set to their default value.
-
-RTF_STYLESHEET_FILE    = 
-
-# Set optional variables used in the generation of an rtf document. 
-# Syntax is similar to doxygen's config file.
-
-RTF_EXTENSIONS_FILE    = 
-
-#---------------------------------------------------------------------------
-# configuration options related to the man page output
-#---------------------------------------------------------------------------
-
-# If the GENERATE_MAN tag is set to YES (the default) Doxygen will 
-# generate man pages
-
-GENERATE_MAN           = NO
-
-# The MAN_OUTPUT tag is used to specify where the man pages will be put. 
-# If a relative path is entered the value of OUTPUT_DIRECTORY will be 
-# put in front of it. If left blank `man' will be used as the default path.
-
-MAN_OUTPUT             = man
-
-# The MAN_EXTENSION tag determines the extension that is added to 
-# the generated man pages (default is the subroutine's section .3)
-
-MAN_EXTENSION          = .3
-
-# If the MAN_LINKS tag is set to YES and Doxygen generates man output, 
-# then it will generate one additional man file for each entity 
-# documented in the real man page(s). These additional files 
-# only source the real man page, but without them the man command 
-# would be unable to find the correct page. The default is NO.
-
-MAN_LINKS              = NO
-
-#---------------------------------------------------------------------------
-# configuration options related to the XML output
-#---------------------------------------------------------------------------
-
-# If the GENERATE_XML tag is set to YES Doxygen will 
-# generate an XML file that captures the structure of 
-# the code including all documentation.
-
-GENERATE_XML           = NO
-
-# The XML_OUTPUT tag is used to specify where the XML pages will be put. 
-# If a relative path is entered the value of OUTPUT_DIRECTORY will be 
-# put in front of it. If left blank `xml' will be used as the default path.
-
-XML_OUTPUT             = xml
-
-# The XML_SCHEMA tag can be used to specify an XML schema, 
-# which can be used by a validating XML parser to check the 
-# syntax of the XML files.
-
-XML_SCHEMA             = 
-
-# The XML_DTD tag can be used to specify an XML DTD, 
-# which can be used by a validating XML parser to check the 
-# syntax of the XML files.
-
-XML_DTD                = 
-
-# If the XML_PROGRAMLISTING tag is set to YES Doxygen will 
-# dump the program listings (including syntax highlighting 
-# and cross-referencing information) to the XML output. Note that 
-# enabling this will significantly increase the size of the XML output.
-
-XML_PROGRAMLISTING     = YES
-
-#---------------------------------------------------------------------------
-# configuration options for the AutoGen Definitions output
-#---------------------------------------------------------------------------
-
-# If the GENERATE_AUTOGEN_DEF tag is set to YES Doxygen will 
-# generate an AutoGen Definitions (see autogen.sf.net) file 
-# that captures the structure of the code including all 
-# documentation. Note that this feature is still experimental 
-# and incomplete at the moment.
-
-GENERATE_AUTOGEN_DEF   = NO
-
-#---------------------------------------------------------------------------
-# configuration options related to the Perl module output
-#---------------------------------------------------------------------------
-
-# If the GENERATE_PERLMOD tag is set to YES Doxygen will 
-# generate a Perl module file that captures the structure of 
-# the code including all documentation. Note that this 
-# feature is still experimental and incomplete at the 
-# moment.
-
-GENERATE_PERLMOD       = NO
-
-# If the PERLMOD_LATEX tag is set to YES Doxygen will generate 
-# the necessary Makefile rules, Perl scripts and LaTeX code to be able 
-# to generate PDF and DVI output from the Perl module output.
-
-PERLMOD_LATEX          = NO
-
-# If the PERLMOD_PRETTY tag is set to YES the Perl module output will be 
-# nicely formatted so it can be parsed by a human reader.  This is useful 
-# if you want to understand what is going on.  On the other hand, if this 
-# tag is set to NO the size of the Perl module output will be much smaller 
-# and Perl will parse it just the same.
-
-PERLMOD_PRETTY         = YES
-
-# The names of the make variables in the generated doxyrules.make file 
-# are prefixed with the string contained in PERLMOD_MAKEVAR_PREFIX. 
-# This is useful so different doxyrules.make files included by the same 
-# Makefile don't overwrite each other's variables.
-
-PERLMOD_MAKEVAR_PREFIX = 
-
-#---------------------------------------------------------------------------
-# Configuration options related to the preprocessor   
-#---------------------------------------------------------------------------
-
-# If the ENABLE_PREPROCESSING tag is set to YES (the default) Doxygen will 
-# evaluate all C-preprocessor directives found in the sources and include 
-# files.
-
-ENABLE_PREPROCESSING   = YES
-
-# If the MACRO_EXPANSION tag is set to YES Doxygen will expand all macro 
-# names in the source code. If set to NO (the default) only conditional 
-# compilation will be performed. Macro expansion can be done in a controlled 
-# way by setting EXPAND_ONLY_PREDEF to YES.
-
-MACRO_EXPANSION        = YES
-
-# If the EXPAND_ONLY_PREDEF and MACRO_EXPANSION tags are both set to YES 
-# then the macro expansion is limited to the macros specified with the 
-# PREDEFINED and EXPAND_AS_DEFINED tags.
-
-EXPAND_ONLY_PREDEF     = YES
-
-# If the SEARCH_INCLUDES tag is set to YES (the default) the includes files 
-# in the INCLUDE_PATH (see below) will be search if a #include is found.
-
-SEARCH_INCLUDES        = YES
-
-# The INCLUDE_PATH tag can be used to specify one or more directories that 
-# contain include files that are not input files but should be processed by 
-# the preprocessor.
-
-INCLUDE_PATH           = 
-
-# You can use the INCLUDE_FILE_PATTERNS tag to specify one or more wildcard 
-# patterns (like *.h and *.hpp) to filter out the header-files in the 
-# directories. If left blank, the patterns specified with FILE_PATTERNS will 
-# be used.
-
-INCLUDE_FILE_PATTERNS  = 
-
-# The PREDEFINED tag can be used to specify one or more macro names that 
-# are defined before the preprocessor is started (similar to the -D option of 
-# gcc). The argument of the tag is a list of macros of the form: name 
-# or name=definition (no spaces). If the definition and the = are 
-# omitted =1 is assumed. To prevent a macro definition from being 
-# undefined via #undef or recursively expanded use the := operator 
-# instead of the = operator.
-
-PREDEFINED             = API_EXPORTED= LIBUSB_CALL= DEFAULT_VISIBILITY=
-
-# If the MACRO_EXPANSION and EXPAND_ONLY_PREDEF tags are set to YES then 
-# this tag can be used to specify a list of macro names that should be expanded. 
-# The macro definition that is found in the sources will be used. 
-# Use the PREDEFINED tag if you want to use a different macro definition.
-
-EXPAND_AS_DEFINED      = 
-
-# If the SKIP_FUNCTION_MACROS tag is set to YES (the default) then 
-# doxygen's preprocessor will remove all function-like macros that are alone 
-# on a line, have an all uppercase name, and do not end with a semicolon. Such 
-# function macros are typically used for boiler-plate code, and will confuse 
-# the parser if not removed.
-
-SKIP_FUNCTION_MACROS   = YES
-
-#---------------------------------------------------------------------------
-# Configuration::additions related to external references   
-#---------------------------------------------------------------------------
-
-# The TAGFILES option can be used to specify one or more tagfiles. 
-# Optionally an initial location of the external documentation 
-# can be added for each tagfile. The format of a tag file without 
-# this location is as follows: 
-#   TAGFILES = file1 file2 ... 
-# Adding location for the tag files is done as follows: 
-#   TAGFILES = file1=loc1 "file2 = loc2" ... 
-# where "loc1" and "loc2" can be relative or absolute paths or 
-# URLs. If a location is present for each tag, the installdox tool 
-# does not have to be run to correct the links.
-# Note that each tag file must have a unique name
-# (where the name does NOT include the path)
-# If a tag file is not located in the directory in which doxygen 
-# is run, you must also specify the path to the tagfile here.
-
-TAGFILES               = 
-
-# When a file name is specified after GENERATE_TAGFILE, doxygen will create 
-# a tag file that is based on the input files it reads.
-
-GENERATE_TAGFILE       = 
-
-# If the ALLEXTERNALS tag is set to YES all external classes will be listed 
-# in the class index. If set to NO only the inherited external classes 
-# will be listed.
-
-ALLEXTERNALS           = NO
-
-# If the EXTERNAL_GROUPS tag is set to YES all external groups will be listed 
-# in the modules index. If set to NO, only the current project's groups will 
-# be listed.
-
-EXTERNAL_GROUPS        = YES
-
-# The PERL_PATH should be the absolute path and name of the perl script 
-# interpreter (i.e. the result of `which perl').
-
-PERL_PATH              = /usr/bin/perl
-
-#---------------------------------------------------------------------------
-# Configuration options related to the dot tool   
-#---------------------------------------------------------------------------
-
-# If the CLASS_DIAGRAMS tag is set to YES (the default) Doxygen will 
-# generate a inheritance diagram (in HTML, RTF and LaTeX) for classes with base 
-# or super classes. Setting the tag to NO turns the diagrams off. Note that 
-# this option is superseded by the HAVE_DOT option below. This is only a 
-# fallback. It is recommended to install and use dot, since it yields more 
-# powerful graphs.
-
-CLASS_DIAGRAMS         = YES
-
-# You can define message sequence charts within doxygen comments using the \msc 
-# command. Doxygen will then run the mscgen tool (see http://www.mcternan.me.uk/mscgen/) to 
-# produce the chart and insert it in the documentation. The MSCGEN_PATH tag allows you to 
-# specify the directory where the mscgen tool resides. If left empty the tool is assumed to 
-# be found in the default search path.
-
-MSCGEN_PATH            = 
-
-# If set to YES, the inheritance and collaboration graphs will hide 
-# inheritance and usage relations if the target is undocumented 
-# or is not a class.
-
-HIDE_UNDOC_RELATIONS   = YES
-
-# If you set the HAVE_DOT tag to YES then doxygen will assume the dot tool is 
-# available from the path. This tool is part of Graphviz, a graph visualization 
-# toolkit from AT&T and Lucent Bell Labs. The other options in this section 
-# have no effect if this option is set to NO (the default)
-
-HAVE_DOT               = NO
-
-# If the CLASS_GRAPH and HAVE_DOT tags are set to YES then doxygen 
-# will generate a graph for each documented class showing the direct and 
-# indirect inheritance relations. Setting this tag to YES will force the 
-# the CLASS_DIAGRAMS tag to NO.
-
-CLASS_GRAPH            = YES
-
-# If the COLLABORATION_GRAPH and HAVE_DOT tags are set to YES then doxygen 
-# will generate a graph for each documented class showing the direct and 
-# indirect implementation dependencies (inheritance, containment, and 
-# class references variables) of the class with other documented classes.
-
-COLLABORATION_GRAPH    = YES
-
-# If the GROUP_GRAPHS and HAVE_DOT tags are set to YES then doxygen 
-# will generate a graph for groups, showing the direct groups dependencies
-
-GROUP_GRAPHS           = YES
-
-# If the UML_LOOK tag is set to YES doxygen will generate inheritance and 
-# collaboration diagrams in a style similar to the OMG's Unified Modeling 
-# Language.
-
-UML_LOOK               = NO
-
-# If set to YES, the inheritance and collaboration graphs will show the 
-# relations between templates and their instances.
-
-TEMPLATE_RELATIONS     = NO
-
-# If the ENABLE_PREPROCESSING, SEARCH_INCLUDES, INCLUDE_GRAPH, and HAVE_DOT 
-# tags are set to YES then doxygen will generate a graph for each documented 
-# file showing the direct and indirect include dependencies of the file with 
-# other documented files.
-
-INCLUDE_GRAPH          = YES
-
-# If the ENABLE_PREPROCESSING, SEARCH_INCLUDES, INCLUDED_BY_GRAPH, and 
-# HAVE_DOT tags are set to YES then doxygen will generate a graph for each 
-# documented header file showing the documented files that directly or 
-# indirectly include this file.
-
-INCLUDED_BY_GRAPH      = YES
-
-# If the CALL_GRAPH, SOURCE_BROWSER and HAVE_DOT tags are set to YES then doxygen will 
-# generate a call dependency graph for every global function or class method. 
-# Note that enabling this option will significantly increase the time of a run. 
-# So in most cases it will be better to enable call graphs for selected 
-# functions only using the \callgraph command.
-
-CALL_GRAPH             = NO
-
-# If the CALLER_GRAPH, SOURCE_BROWSER and HAVE_DOT tags are set to YES then doxygen will 
-# generate a caller dependency graph for every global function or class method. 
-# Note that enabling this option will significantly increase the time of a run. 
-# So in most cases it will be better to enable caller graphs for selected 
-# functions only using the \callergraph command.
-
-CALLER_GRAPH           = NO
-
-# If the GRAPHICAL_HIERARCHY and HAVE_DOT tags are set to YES then doxygen 
-# will graphical hierarchy of all classes instead of a textual one.
-
-GRAPHICAL_HIERARCHY    = YES
-
-# If the DIRECTORY_GRAPH, SHOW_DIRECTORIES and HAVE_DOT tags are set to YES 
-# then doxygen will show the dependencies a directory has on other directories 
-# in a graphical way. The dependency relations are determined by the #include
-# relations between the files in the directories.
-
-DIRECTORY_GRAPH        = YES
-
-# The DOT_IMAGE_FORMAT tag can be used to set the image format of the images 
-# generated by dot. Possible values are png, jpg, or gif
-# If left blank png will be used.
-
-DOT_IMAGE_FORMAT       = png
-
-# The tag DOT_PATH can be used to specify the path where the dot tool can be 
-# found. If left blank, it is assumed the dot tool can be found in the path.
-
-DOT_PATH               = 
-
-# The DOTFILE_DIRS tag can be used to specify one or more directories that 
-# contain dot files that are included in the documentation (see the 
-# \dotfile command).
-
-DOTFILE_DIRS           = 
-
-# The MAX_DOT_GRAPH_MAX_NODES tag can be used to set the maximum number of 
-# nodes that will be shown in the graph. If the number of nodes in a graph 
-# becomes larger than this value, doxygen will truncate the graph, which is 
-# visualized by representing a node as a red box. Note that doxygen if the number 
-# of direct children of the root node in a graph is already larger than 
-# MAX_DOT_GRAPH_NOTES then the graph will not be shown at all. Also note 
-# that the size of a graph can be further restricted by MAX_DOT_GRAPH_DEPTH.
-
-DOT_GRAPH_MAX_NODES    = 50
-
-# The MAX_DOT_GRAPH_DEPTH tag can be used to set the maximum depth of the 
-# graphs generated by dot. A depth value of 3 means that only nodes reachable 
-# from the root by following a path via at most 3 edges will be shown. Nodes 
-# that lay further from the root node will be omitted. Note that setting this 
-# option to 1 or 2 may greatly reduce the computation time needed for large 
-# code bases. Also note that the size of a graph can be further restricted by 
-# DOT_GRAPH_MAX_NODES. Using a depth of 0 means no depth restriction.
-
-MAX_DOT_GRAPH_DEPTH    = 0
-
-# Set the DOT_TRANSPARENT tag to YES to generate images with a transparent 
-# background. This is disabled by default, which results in a white background. 
-# Warning: Depending on the platform used, enabling this option may lead to 
-# badly anti-aliased labels on the edges of a graph (i.e. they become hard to 
-# read).
-
-DOT_TRANSPARENT        = NO
-
-# Set the DOT_MULTI_TARGETS tag to YES allow dot to generate multiple output 
-# files in one run (i.e. multiple -o and -T options on the command line). This 
-# makes dot run faster, but since only newer versions of dot (>1.8.10) 
-# support this, this feature is disabled by default.
-
-DOT_MULTI_TARGETS      = NO
-
-# If the GENERATE_LEGEND tag is set to YES (the default) Doxygen will 
-# generate a legend page explaining the meaning of the various boxes and 
-# arrows in the dot generated graphs.
-
-GENERATE_LEGEND        = YES
-
-# If the DOT_CLEANUP tag is set to YES (the default) Doxygen will 
-# remove the intermediate dot files that are used to generate 
-# the various graphs.
-
-DOT_CLEANUP            = YES
-
-#---------------------------------------------------------------------------
-# Configuration::additions related to the search engine   
-#---------------------------------------------------------------------------
-
-# The SEARCHENGINE tag specifies whether or not a search engine should be 
-# used. If set to NO the values of all tags below this one will be ignored.
-
-SEARCHENGINE           = NO
diff --git a/third_party/libusb/examples/Makefile.am b/third_party/libusb/examples/Makefile.am
deleted file mode 100644
index 846af15..0000000
--- a/third_party/libusb/examples/Makefile.am
+++ /dev/null
@@ -1,21 +0,0 @@
-INCLUDES = -I$(top_srcdir)/libusb
-noinst_PROGRAMS = lsusb
-
-lsusb_SOURCES = lsusb.c
-lsusb_LDADD = ../libusb/libusb-1.0.la -lusb-1.0
-
-if HAVE_SIGACTION
-dpfp_SOURCES = dpfp.c
-dpfp_LDADD = ../libusb/libusb-1.0.la -lusb-1.0
-noinst_PROGRAMS += dpfp
-endif
-
-if THREADS_POSIX
-if HAVE_SIGACTION
-dpfp_threaded_SOURCES = dpfp_threaded.c
-dpfp_threaded_CFLAGS = $(THREAD_CFLAGS) $(AM_CFLAGS)
-dpfp_threaded_LDADD = ../libusb/libusb-1.0.la -lusb-1.0
-noinst_PROGRAMS += dpfp_threaded
-endif
-endif
-
diff --git a/third_party/libusb/examples/dpfp.c b/third_party/libusb/examples/dpfp.c
deleted file mode 100644
index 1b3c3a4..0000000
--- a/third_party/libusb/examples/dpfp.c
+++ /dev/null
@@ -1,507 +0,0 @@
-/*
- * libusb example program to manipulate U.are.U 4000B fingerprint scanner.
- * Copyright (C) 2007 Daniel Drake <dsd@gentoo.org>
- *
- * Basic image capture program only, does not consider the powerup quirks or
- * the fact that image encryption may be enabled. Not expected to work
- * flawlessly all of the time.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#include <errno.h>
-#include <signal.h>
-#include <string.h>
-#include <stdio.h>
-#include <stdlib.h>
-
-#include <libusb.h>
-
-#define EP_INTR			(1 | LIBUSB_ENDPOINT_IN)
-#define EP_DATA			(2 | LIBUSB_ENDPOINT_IN)
-#define CTRL_IN			(LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_ENDPOINT_IN)
-#define CTRL_OUT		(LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_ENDPOINT_OUT)
-#define USB_RQ			0x04
-#define INTR_LENGTH		64
-
-enum {
-	MODE_INIT = 0x00,
-	MODE_AWAIT_FINGER_ON = 0x10,
-	MODE_AWAIT_FINGER_OFF = 0x12,
-	MODE_CAPTURE = 0x20,
-	MODE_SHUT_UP = 0x30,
-	MODE_READY = 0x80,
-};
-
-static int next_state(void);
-
-enum {
-	STATE_AWAIT_MODE_CHANGE_AWAIT_FINGER_ON = 1,
-	STATE_AWAIT_IRQ_FINGER_DETECTED,
-	STATE_AWAIT_MODE_CHANGE_CAPTURE,
-	STATE_AWAIT_IMAGE,
-	STATE_AWAIT_MODE_CHANGE_AWAIT_FINGER_OFF,
-	STATE_AWAIT_IRQ_FINGER_REMOVED,
-};
-
-static int state = 0;
-static struct libusb_device_handle *devh = NULL;
-static unsigned char imgbuf[0x1b340];
-static unsigned char irqbuf[INTR_LENGTH];
-static struct libusb_transfer *img_transfer = NULL;
-static struct libusb_transfer *irq_transfer = NULL;
-static int img_idx = 0;
-static int do_exit = 0;
-
-static int find_dpfp_device(void)
-{
-	devh = libusb_open_device_with_vid_pid(NULL, 0x05ba, 0x000a);
-	return devh ? 0 : -EIO;
-}
-
-static int print_f0_data(void)
-{
-	unsigned char data[0x10];
-	int r;
-	unsigned int i;
-
-	r = libusb_control_transfer(devh, CTRL_IN, USB_RQ, 0xf0, 0, data,
-		sizeof(data), 0);
-	if (r < 0) {
-		fprintf(stderr, "F0 error %d\n", r);
-		return r;
-	}
-	if ((unsigned int) r < sizeof(data)) {
-		fprintf(stderr, "short read (%d)\n", r);
-		return -1;
-	}
-
-	printf("F0 data:");
-	for (i = 0; i < sizeof(data); i++)
-		printf("%02x ", data[i]);
-	printf("\n");
-	return 0;
-}
-
-static int get_hwstat(unsigned char *status)
-{
-	int r;
-
-	r = libusb_control_transfer(devh, CTRL_IN, USB_RQ, 0x07, 0, status, 1, 0);
-	if (r < 0) {
-		fprintf(stderr, "read hwstat error %d\n", r);
-		return r;
-	}
-	if ((unsigned int) r < 1) {
-		fprintf(stderr, "short read (%d)\n", r);
-		return -1;
-	}
-
-	printf("hwstat reads %02x\n", *status);
-	return 0;
-}
-
-static int set_hwstat(unsigned char data)
-{
-	int r;
-
-	printf("set hwstat to %02x\n", data);
-	r = libusb_control_transfer(devh, CTRL_OUT, USB_RQ, 0x07, 0, &data, 1, 0);
-	if (r < 0) {
-		fprintf(stderr, "set hwstat error %d\n", r);
-		return r;
-	}
-	if ((unsigned int) r < 1) {
-		fprintf(stderr, "short write (%d)", r);
-		return -1;
-	}
-
-	return 0;
-}
-
-static int set_mode(unsigned char data)
-{
-	int r;
-	printf("set mode %02x\n", data);
-
-	r = libusb_control_transfer(devh, CTRL_OUT, USB_RQ, 0x4e, 0, &data, 1, 0);
-	if (r < 0) {
-		fprintf(stderr, "set mode error %d\n", r);
-		return r;
-	}
-	if ((unsigned int) r < 1) {
-		fprintf(stderr, "short write (%d)", r);
-		return -1;
-	}
-
-	return 0;
-}
-
-static void LIBUSB_CALL cb_mode_changed(struct libusb_transfer *transfer)
-{
-	if (transfer->status != LIBUSB_TRANSFER_COMPLETED) {
-		fprintf(stderr, "mode change transfer not completed!\n");
-		do_exit = 2;
-	}
-
-	printf("async cb_mode_changed length=%d actual_length=%d\n",
-		transfer->length, transfer->actual_length);
-	if (next_state() < 0)
-		do_exit = 2;
-}
-
-static int set_mode_async(unsigned char data)
-{
-	unsigned char *buf = malloc(LIBUSB_CONTROL_SETUP_SIZE + 1);
-	struct libusb_transfer *transfer;
-
-	if (!buf)
-		return -ENOMEM;
-
-	transfer = libusb_alloc_transfer(0);
-	if (!transfer) {
-		free(buf);
-		return -ENOMEM;
-	}
-
-	printf("async set mode %02x\n", data);
-	libusb_fill_control_setup(buf, CTRL_OUT, USB_RQ, 0x4e, 0, 1);
-	buf[LIBUSB_CONTROL_SETUP_SIZE] = data;
-	libusb_fill_control_transfer(transfer, devh, buf, cb_mode_changed, NULL,
-		1000);
-
-	transfer->flags = LIBUSB_TRANSFER_SHORT_NOT_OK
-		| LIBUSB_TRANSFER_FREE_BUFFER | LIBUSB_TRANSFER_FREE_TRANSFER;
-	return libusb_submit_transfer(transfer);
-}
-
-static int do_sync_intr(unsigned char *data)
-{
-	int r;
-	int transferred;
-
-	r = libusb_interrupt_transfer(devh, EP_INTR, data, INTR_LENGTH,
-		&transferred, 1000);
-	if (r < 0) {
-		fprintf(stderr, "intr error %d\n", r);
-		return r;
-	}
-	if (transferred < INTR_LENGTH) {
-		fprintf(stderr, "short read (%d)\n", r);
-		return -1;
-	}
-
-	printf("recv interrupt %04x\n", *((uint16_t *) data));
-	return 0;
-}
-
-static int sync_intr(unsigned char type)
-{
-	int r;
-	unsigned char data[INTR_LENGTH];
-
-	while (1) {
-		r = do_sync_intr(data);
-		if (r < 0)
-			return r;
-		if (data[0] == type)
-			return 0;
-	}
-}
-
-static int save_to_file(unsigned char *data)
-{
-	FILE *fd;
-	char filename[64];
-
-	sprintf(filename, "finger%d.pgm", img_idx++);
-	fd = fopen(filename, "w");
-	if (!fd)
-		return -1;
-
-	fputs("P5 384 289 255 ", fd);
-	(void) fwrite(data + 64, 1, 384*289, fd);
-	fclose(fd);
-	printf("saved image to %s\n", filename);
-	return 0;
-}
-
-static int next_state(void)
-{
-	int r = 0;
-	printf("old state: %d\n", state);
-	switch (state) {
-	case STATE_AWAIT_IRQ_FINGER_REMOVED:
-		state = STATE_AWAIT_MODE_CHANGE_AWAIT_FINGER_ON;
-		r = set_mode_async(MODE_AWAIT_FINGER_ON);
-		break;
-	case STATE_AWAIT_MODE_CHANGE_AWAIT_FINGER_ON:
-		state = STATE_AWAIT_IRQ_FINGER_DETECTED;
-		break;
-	case STATE_AWAIT_IRQ_FINGER_DETECTED:
-		state = STATE_AWAIT_MODE_CHANGE_CAPTURE;
-		r = set_mode_async(MODE_CAPTURE);
-		break;
-	case STATE_AWAIT_MODE_CHANGE_CAPTURE:
-		state = STATE_AWAIT_IMAGE;
-		break;
-	case STATE_AWAIT_IMAGE:
-		state = STATE_AWAIT_MODE_CHANGE_AWAIT_FINGER_OFF;
-		r = set_mode_async(MODE_AWAIT_FINGER_OFF);
-		break;
-	case STATE_AWAIT_MODE_CHANGE_AWAIT_FINGER_OFF:
-		state = STATE_AWAIT_IRQ_FINGER_REMOVED;
-		break;
-	default:
-		printf("unrecognised state %d\n", state);
-	}
-	if (r < 0) {
-		fprintf(stderr, "error detected changing state\n");
-		return r;
-	}
-
-	printf("new state: %d\n", state);
-	return 0;
-}
-
-static void LIBUSB_CALL cb_irq(struct libusb_transfer *transfer)
-{
-	unsigned char irqtype = transfer->buffer[0];
-
-	if (transfer->status != LIBUSB_TRANSFER_COMPLETED) {
-		fprintf(stderr, "irq transfer status %d?\n", transfer->status);
-		do_exit = 2;
-		libusb_free_transfer(transfer);
-		irq_transfer = NULL;
-		return;
-	}
-
-	printf("IRQ callback %02x\n", irqtype);
-	switch (state) {
-	case STATE_AWAIT_IRQ_FINGER_DETECTED:
-		if (irqtype == 0x01) {
-			if (next_state() < 0) {
-				do_exit = 2;
-				return;
-			}
-		} else {
-			printf("finger-on-sensor detected in wrong state!\n");
-		}
-		break;
-	case STATE_AWAIT_IRQ_FINGER_REMOVED:
-		if (irqtype == 0x02) {
-			if (next_state() < 0) {
-				do_exit = 2;
-				return;
-			}
-		} else {
-			printf("finger-on-sensor detected in wrong state!\n");
-		}
-		break;
-	}
-	if (libusb_submit_transfer(irq_transfer) < 0)
-		do_exit = 2;
-}
-
-static void LIBUSB_CALL cb_img(struct libusb_transfer *transfer)
-{
-	if (transfer->status != LIBUSB_TRANSFER_COMPLETED) {
-		fprintf(stderr, "img transfer status %d?\n", transfer->status);
-		do_exit = 2;
-		libusb_free_transfer(transfer);
-		img_transfer = NULL;
-		return;
-	}
-
-	printf("Image callback\n");
-	save_to_file(imgbuf);
-	if (next_state() < 0) {
-		do_exit = 2;
-		return;
-	}
-	if (libusb_submit_transfer(img_transfer) < 0)
-		do_exit = 2;
-}
-
-static int init_capture(void)
-{
-	int r;
-
-	r = libusb_submit_transfer(irq_transfer);
-	if (r < 0)
-		return r;
-
-	r = libusb_submit_transfer(img_transfer);
-	if (r < 0) {
-		libusb_cancel_transfer(irq_transfer);
-		while (irq_transfer)
-			if (libusb_handle_events(NULL) < 0)
-				break;
-		return r;
-	}
-
-	/* start state machine */
-	state = STATE_AWAIT_IRQ_FINGER_REMOVED;
-	return next_state();
-}
-
-static int do_init(void)
-{
-	unsigned char status;
-	int r;
-
-	r = get_hwstat(&status);
-	if (r < 0)
-		return r;
-
-	if (!(status & 0x80)) {
-		r = set_hwstat(status | 0x80);
-		if (r < 0)
-			return r;
-		r = get_hwstat(&status);
-		if (r < 0)
-			return r;
-	}
-
-	status &= ~0x80;
-	r = set_hwstat(status);
-	if (r < 0)
-		return r;
-
-	r = get_hwstat(&status);
-	if (r < 0)
-		return r;
-
-	r = sync_intr(0x56);
-	if (r < 0)
-		return r;
-
-	return 0;
-}
-
-static int alloc_transfers(void)
-{
-	img_transfer = libusb_alloc_transfer(0);
-	if (!img_transfer)
-		return -ENOMEM;
-
-	irq_transfer = libusb_alloc_transfer(0);
-	if (!irq_transfer)
-		return -ENOMEM;
-
-	libusb_fill_bulk_transfer(img_transfer, devh, EP_DATA, imgbuf,
-		sizeof(imgbuf), cb_img, NULL, 0);
-	libusb_fill_interrupt_transfer(irq_transfer, devh, EP_INTR, irqbuf,
-		sizeof(irqbuf), cb_irq, NULL, 0);
-
-	return 0;
-}
-
-static void sighandler(int signum)
-{
-	do_exit = 1;
-}
-
-int main(void)
-{
-	struct sigaction sigact;
-	int r = 1;
-
-	r = libusb_init(NULL);
-	if (r < 0) {
-		fprintf(stderr, "failed to initialise libusb\n");
-		exit(1);
-	}
-
-	r = find_dpfp_device();
-	if (r < 0) {
-		fprintf(stderr, "Could not find/open device\n");
-		goto out;
-	}
-
-	r = libusb_claim_interface(devh, 0);
-	if (r < 0) {
-		fprintf(stderr, "usb_claim_interface error %d\n", r);
-		goto out;
-	}
-	printf("claimed interface\n");
-
-	r = print_f0_data();
-	if (r < 0)
-		goto out_release;
-
-	r = do_init();
-	if (r < 0)
-		goto out_deinit;
-
-	/* async from here onwards */
-
-	r = alloc_transfers();
-	if (r < 0)
-		goto out_deinit;
-
-	r = init_capture();
-	if (r < 0)
-		goto out_deinit;
-
-	sigact.sa_handler = sighandler;
-	sigemptyset(&sigact.sa_mask);
-	sigact.sa_flags = 0;
-	sigaction(SIGINT, &sigact, NULL);
-	sigaction(SIGTERM, &sigact, NULL);
-	sigaction(SIGQUIT, &sigact, NULL);
-
-	while (!do_exit) {
-		r = libusb_handle_events(NULL);
-		if (r < 0)
-			goto out_deinit;
-	}
-
-	printf("shutting down...\n");
-
-	if (irq_transfer) {
-		r = libusb_cancel_transfer(irq_transfer);
-		if (r < 0)
-			goto out_deinit;
-	}
-
-	if (img_transfer) {
-		r = libusb_cancel_transfer(img_transfer);
-		if (r < 0)
-			goto out_deinit;
-	}
-
-	while (irq_transfer || img_transfer)
-		if (libusb_handle_events(NULL) < 0)
-			break;
-
-	if (do_exit == 1)
-		r = 0;
-	else
-		r = 1;
-
-out_deinit:
-	libusb_free_transfer(img_transfer);
-	libusb_free_transfer(irq_transfer);
-	set_mode(0);
-	set_hwstat(0x80);
-out_release:
-	libusb_release_interface(devh, 0);
-out:
-	libusb_close(devh);
-	libusb_exit(NULL);
-	return r >= 0 ? r : -r;
-}
-
diff --git a/third_party/libusb/examples/dpfp_threaded.c b/third_party/libusb/examples/dpfp_threaded.c
deleted file mode 100644
index c3d314d..0000000
--- a/third_party/libusb/examples/dpfp_threaded.c
+++ /dev/null
@@ -1,545 +0,0 @@
-/*
- * libusb example program to manipulate U.are.U 4000B fingerprint scanner.
- * Copyright (C) 2007 Daniel Drake <dsd@gentoo.org>
- *
- * Basic image capture program only, does not consider the powerup quirks or
- * the fact that image encryption may be enabled. Not expected to work
- * flawlessly all of the time.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#include <errno.h>
-#include <pthread.h>
-#include <signal.h>
-#include <string.h>
-#include <stdio.h>
-#include <stdlib.h>
-
-#include <libusb.h>
-
-#define EP_INTR			(1 | LIBUSB_ENDPOINT_IN)
-#define EP_DATA			(2 | LIBUSB_ENDPOINT_IN)
-#define CTRL_IN			(LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_ENDPOINT_IN)
-#define CTRL_OUT		(LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_ENDPOINT_OUT)
-#define USB_RQ			0x04
-#define INTR_LENGTH		64
-
-enum {
-	MODE_INIT = 0x00,
-	MODE_AWAIT_FINGER_ON = 0x10,
-	MODE_AWAIT_FINGER_OFF = 0x12,
-	MODE_CAPTURE = 0x20,
-	MODE_SHUT_UP = 0x30,
-	MODE_READY = 0x80,
-};
-
-static int next_state(void);
-
-enum {
-	STATE_AWAIT_MODE_CHANGE_AWAIT_FINGER_ON = 1,
-	STATE_AWAIT_IRQ_FINGER_DETECTED,
-	STATE_AWAIT_MODE_CHANGE_CAPTURE,
-	STATE_AWAIT_IMAGE,
-	STATE_AWAIT_MODE_CHANGE_AWAIT_FINGER_OFF,
-	STATE_AWAIT_IRQ_FINGER_REMOVED,
-};
-
-static int state = 0;
-static struct libusb_device_handle *devh = NULL;
-static unsigned char imgbuf[0x1b340];
-static unsigned char irqbuf[INTR_LENGTH];
-static struct libusb_transfer *img_transfer = NULL;
-static struct libusb_transfer *irq_transfer = NULL;
-static int img_idx = 0;
-static int do_exit = 0;
-
-static pthread_t poll_thread;
-static pthread_cond_t exit_cond = PTHREAD_COND_INITIALIZER;
-static pthread_mutex_t exit_cond_lock = PTHREAD_MUTEX_INITIALIZER;
-
-static void request_exit(int code)
-{
-	do_exit = code;
-	pthread_cond_signal(&exit_cond);
-}
-
-static void *poll_thread_main(void *arg)
-{
-	int r = 0;
-	printf("poll thread running\n");
-
-	while (!do_exit) {
-		struct timeval tv = { 1, 0 };
-		r = libusb_handle_events_timeout(NULL, &tv);
-		if (r < 0) {
-			request_exit(2);
-			break;
-		}
-	}
-
-	printf("poll thread shutting down\n");
-	return NULL;
-}
-
-static int find_dpfp_device(void)
-{
-	devh = libusb_open_device_with_vid_pid(NULL, 0x05ba, 0x000a);
-	return devh ? 0 : -EIO;
-}
-
-static int print_f0_data(void)
-{
-	unsigned char data[0x10];
-	int r;
-	unsigned int i;
-
-	r = libusb_control_transfer(devh, CTRL_IN, USB_RQ, 0xf0, 0, data,
-		sizeof(data), 0);
-	if (r < 0) {
-		fprintf(stderr, "F0 error %d\n", r);
-		return r;
-	}
-	if ((unsigned int) r < sizeof(data)) {
-		fprintf(stderr, "short read (%d)\n", r);
-		return -1;
-	}
-
-	printf("F0 data:");
-	for (i = 0; i < sizeof(data); i++)
-		printf("%02x ", data[i]);
-	printf("\n");
-	return 0;
-}
-
-static int get_hwstat(unsigned char *status)
-{
-	int r;
-
-	r = libusb_control_transfer(devh, CTRL_IN, USB_RQ, 0x07, 0, status, 1, 0);
-	if (r < 0) {
-		fprintf(stderr, "read hwstat error %d\n", r);
-		return r;
-	}
-	if ((unsigned int) r < 1) {
-		fprintf(stderr, "short read (%d)\n", r);
-		return -1;
-	}
-
-	printf("hwstat reads %02x\n", *status);
-	return 0;
-}
-
-static int set_hwstat(unsigned char data)
-{
-	int r;
-
-	printf("set hwstat to %02x\n", data);
-	r = libusb_control_transfer(devh, CTRL_OUT, USB_RQ, 0x07, 0, &data, 1, 0);
-	if (r < 0) {
-		fprintf(stderr, "set hwstat error %d\n", r);
-		return r;
-	}
-	if ((unsigned int) r < 1) {
-		fprintf(stderr, "short write (%d)", r);
-		return -1;
-	}
-
-	return 0;
-}
-
-static int set_mode(unsigned char data)
-{
-	int r;
-	printf("set mode %02x\n", data);
-
-	r = libusb_control_transfer(devh, CTRL_OUT, USB_RQ, 0x4e, 0, &data, 1, 0);
-	if (r < 0) {
-		fprintf(stderr, "set mode error %d\n", r);
-		return r;
-	}
-	if ((unsigned int) r < 1) {
-		fprintf(stderr, "short write (%d)", r);
-		return -1;
-	}
-
-	return 0;
-}
-
-static void LIBUSB_CALL cb_mode_changed(struct libusb_transfer *transfer)
-{
-	if (transfer->status != LIBUSB_TRANSFER_COMPLETED) {
-		fprintf(stderr, "mode change transfer not completed!\n");
-		request_exit(2);
-	}
-
-	printf("async cb_mode_changed length=%d actual_length=%d\n",
-		transfer->length, transfer->actual_length);
-	if (next_state() < 0)
-		request_exit(2);
-}
-
-static int set_mode_async(unsigned char data)
-{
-	unsigned char *buf = malloc(LIBUSB_CONTROL_SETUP_SIZE + 1);
-	struct libusb_transfer *transfer;
-
-	if (!buf)
-		return -ENOMEM;
-
-	transfer = libusb_alloc_transfer(0);
-	if (!transfer) {
-		free(buf);
-		return -ENOMEM;
-	}
-
-	printf("async set mode %02x\n", data);
-	libusb_fill_control_setup(buf, CTRL_OUT, USB_RQ, 0x4e, 0, 1);
-	buf[LIBUSB_CONTROL_SETUP_SIZE] = data;
-	libusb_fill_control_transfer(transfer, devh, buf, cb_mode_changed, NULL,
-		1000);
-
-	transfer->flags = LIBUSB_TRANSFER_SHORT_NOT_OK
-		| LIBUSB_TRANSFER_FREE_BUFFER | LIBUSB_TRANSFER_FREE_TRANSFER;
-	return libusb_submit_transfer(transfer);
-}
-
-static int do_sync_intr(unsigned char *data)
-{
-	int r;
-	int transferred;
-
-	r = libusb_interrupt_transfer(devh, EP_INTR, data, INTR_LENGTH,
-		&transferred, 1000);
-	if (r < 0) {
-		fprintf(stderr, "intr error %d\n", r);
-		return r;
-	}
-	if (transferred < INTR_LENGTH) {
-		fprintf(stderr, "short read (%d)\n", r);
-		return -1;
-	}
-
-	printf("recv interrupt %04x\n", *((uint16_t *) data));
-	return 0;
-}
-
-static int sync_intr(unsigned char type)
-{
-	int r;
-	unsigned char data[INTR_LENGTH];
-
-	while (1) {
-		r = do_sync_intr(data);
-		if (r < 0)
-			return r;
-		if (data[0] == type)
-			return 0;
-	}
-}
-
-static int save_to_file(unsigned char *data)
-{
-	FILE *fd;
-	char filename[64];
-
-	sprintf(filename, "finger%d.pgm", img_idx++);
-	fd = fopen(filename, "w");
-	if (!fd)
-		return -1;
-
-	fputs("P5 384 289 255 ", fd);
-	(void) fwrite(data + 64, 1, 384*289, fd);
-	fclose(fd);
-	printf("saved image to %s\n", filename);
-	return 0;
-}
-
-static int next_state(void)
-{
-	int r = 0;
-	printf("old state: %d\n", state);
-	switch (state) {
-	case STATE_AWAIT_IRQ_FINGER_REMOVED:
-		state = STATE_AWAIT_MODE_CHANGE_AWAIT_FINGER_ON;
-		r = set_mode_async(MODE_AWAIT_FINGER_ON);
-		break;
-	case STATE_AWAIT_MODE_CHANGE_AWAIT_FINGER_ON:
-		state = STATE_AWAIT_IRQ_FINGER_DETECTED;
-		break;
-	case STATE_AWAIT_IRQ_FINGER_DETECTED:
-		state = STATE_AWAIT_MODE_CHANGE_CAPTURE;
-		r = set_mode_async(MODE_CAPTURE);
-		break;
-	case STATE_AWAIT_MODE_CHANGE_CAPTURE:
-		state = STATE_AWAIT_IMAGE;
-		break;
-	case STATE_AWAIT_IMAGE:
-		state = STATE_AWAIT_MODE_CHANGE_AWAIT_FINGER_OFF;
-		r = set_mode_async(MODE_AWAIT_FINGER_OFF);
-		break;
-	case STATE_AWAIT_MODE_CHANGE_AWAIT_FINGER_OFF:
-		state = STATE_AWAIT_IRQ_FINGER_REMOVED;
-		break;
-	default:
-		printf("unrecognised state %d\n", state);
-	}
-	if (r < 0) {
-		fprintf(stderr, "error detected changing state\n");
-		return r;
-	}
-
-	printf("new state: %d\n", state);
-	return 0;
-}
-
-static void LIBUSB_CALL cb_irq(struct libusb_transfer *transfer)
-{
-	unsigned char irqtype = transfer->buffer[0];
-
-	if (transfer->status != LIBUSB_TRANSFER_COMPLETED) {
-		fprintf(stderr, "irq transfer status %d?\n", transfer->status);
-		irq_transfer = NULL;
-		request_exit(2);
-		return;
-	}
-
-	printf("IRQ callback %02x\n", irqtype);
-	switch (state) {
-	case STATE_AWAIT_IRQ_FINGER_DETECTED:
-		if (irqtype == 0x01) {
-			if (next_state() < 0) {
-				request_exit(2);
-				return;
-			}
-		} else {
-			printf("finger-on-sensor detected in wrong state!\n");
-		}
-		break;
-	case STATE_AWAIT_IRQ_FINGER_REMOVED:
-		if (irqtype == 0x02) {
-			if (next_state() < 0) {
-				request_exit(2);
-				return;
-			}
-		} else {
-			printf("finger-on-sensor detected in wrong state!\n");
-		}
-		break;
-	}
-	if (libusb_submit_transfer(irq_transfer) < 0)
-		request_exit(2);
-}
-
-static void LIBUSB_CALL cb_img(struct libusb_transfer *transfer)
-{
-	if (transfer->status != LIBUSB_TRANSFER_COMPLETED) {
-		fprintf(stderr, "img transfer status %d?\n", transfer->status);
-		img_transfer = NULL;
-		request_exit(2);
-		return;
-	}
-
-	printf("Image callback\n");
-	save_to_file(imgbuf);
-	if (next_state() < 0) {
-		request_exit(2);
-		return;
-	}
-	if (libusb_submit_transfer(img_transfer) < 0)
-		request_exit(2);
-}
-
-static int init_capture(void)
-{
-	int r;
-
-	r = libusb_submit_transfer(irq_transfer);
-	if (r < 0)
-		return r;
-
-	r = libusb_submit_transfer(img_transfer);
-	if (r < 0) {
-		libusb_cancel_transfer(irq_transfer);
-		while (irq_transfer)
-			if (libusb_handle_events(NULL) < 0)
-				break;
-		return r;
-	}
-
-	/* start state machine */
-	state = STATE_AWAIT_IRQ_FINGER_REMOVED;
-	return next_state();
-}
-
-static int do_init(void)
-{
-	unsigned char status;
-	int r;
-
-	r = get_hwstat(&status);
-	if (r < 0)
-		return r;
-
-	if (!(status & 0x80)) {
-		r = set_hwstat(status | 0x80);
-		if (r < 0)
-			return r;
-		r = get_hwstat(&status);
-		if (r < 0)
-			return r;
-	}
-
-	status &= ~0x80;
-	r = set_hwstat(status);
-	if (r < 0)
-		return r;
-
-	r = get_hwstat(&status);
-	if (r < 0)
-		return r;
-
-	r = sync_intr(0x56);
-	if (r < 0)
-		return r;
-
-	return 0;
-}
-
-static int alloc_transfers(void)
-{
-	img_transfer = libusb_alloc_transfer(0);
-	if (!img_transfer)
-		return -ENOMEM;
-
-	irq_transfer = libusb_alloc_transfer(0);
-	if (!irq_transfer)
-		return -ENOMEM;
-
-	libusb_fill_bulk_transfer(img_transfer, devh, EP_DATA, imgbuf,
-		sizeof(imgbuf), cb_img, NULL, 0);
-	libusb_fill_interrupt_transfer(irq_transfer, devh, EP_INTR, irqbuf,
-		sizeof(irqbuf), cb_irq, NULL, 0);
-
-	return 0;
-}
-
-static void sighandler(int signum)
-{
-	request_exit(1);
-}
-
-int main(void)
-{
-	struct sigaction sigact;
-	int r = 1;
-
-	r = libusb_init(NULL);
-	if (r < 0) {
-		fprintf(stderr, "failed to initialise libusb\n");
-		exit(1);
-	}
-
-	r = find_dpfp_device();
-	if (r < 0) {
-		fprintf(stderr, "Could not find/open device\n");
-		goto out;
-	}
-
-	r = libusb_claim_interface(devh, 0);
-	if (r < 0) {
-		fprintf(stderr, "usb_claim_interface error %d %s\n", r, strerror(-r));
-		goto out;
-	}
-	printf("claimed interface\n");
-
-	r = print_f0_data();
-	if (r < 0)
-		goto out_release;
-
-	r = do_init();
-	if (r < 0)
-		goto out_deinit;
-
-	/* async from here onwards */
-
-	sigact.sa_handler = sighandler;
-	sigemptyset(&sigact.sa_mask);
-	sigact.sa_flags = 0;
-	sigaction(SIGINT, &sigact, NULL);
-	sigaction(SIGTERM, &sigact, NULL);
-	sigaction(SIGQUIT, &sigact, NULL);
-
-	r = pthread_create(&poll_thread, NULL, poll_thread_main, NULL);
-	if (r)
-		goto out_deinit;
-
-	r = alloc_transfers();
-	if (r < 0) {
-		request_exit(1);
-		pthread_join(poll_thread, NULL);
-		goto out_deinit;
-	}
-
-	r = init_capture();
-	if (r < 0) {
-		request_exit(1);
-		pthread_join(poll_thread, NULL);
-		goto out_deinit;
-	}
-
-	while (!do_exit) {
-		pthread_mutex_lock(&exit_cond_lock);
-		pthread_cond_wait(&exit_cond, &exit_cond_lock);
-		pthread_mutex_unlock(&exit_cond_lock);
-	}
-
-	printf("shutting down...\n");
-	pthread_join(poll_thread, NULL);
-
-	r = libusb_cancel_transfer(irq_transfer);
-	if (r < 0) {
-		request_exit(1);
-		goto out_deinit;
-	}
-
-	r = libusb_cancel_transfer(img_transfer);
-	if (r < 0) {
-		request_exit(1);
-		goto out_deinit;
-	}
-
-	while (img_transfer || irq_transfer)
-		if (libusb_handle_events(NULL) < 0)
-			break;
-
-	if (do_exit == 1)
-		r = 0;
-	else
-		r = 1;
-
-out_deinit:
-	libusb_free_transfer(img_transfer);
-	libusb_free_transfer(irq_transfer);
-	set_mode(0);
-	set_hwstat(0x80);
-out_release:
-	libusb_release_interface(devh, 0);
-out:
-	libusb_close(devh);
-	libusb_exit(NULL);
-	return r >= 0 ? r : -r;
-}
-
diff --git a/third_party/libusb/examples/lsusb.c b/third_party/libusb/examples/lsusb.c
deleted file mode 100644
index 6ab8917..0000000
--- a/third_party/libusb/examples/lsusb.c
+++ /dev/null
@@ -1,64 +0,0 @@
-/*
- * libusb example program to list devices on the bus
- * Copyright (C) 2007 Daniel Drake <dsd@gentoo.org>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#include <stdio.h>
-#include <sys/types.h>
-
-#include <libusb.h>
-
-static void print_devs(libusb_device **devs)
-{
-	libusb_device *dev;
-	int i = 0;
-
-	while ((dev = devs[i++]) != NULL) {
-		struct libusb_device_descriptor desc;
-		int r = libusb_get_device_descriptor(dev, &desc);
-		if (r < 0) {
-			fprintf(stderr, "failed to get device descriptor");
-			return;
-		}
-
-		printf("%04x:%04x (bus %d, device %d)\n",
-			desc.idVendor, desc.idProduct,
-			libusb_get_bus_number(dev), libusb_get_device_address(dev));
-	}
-}
-
-int main(void)
-{
-	libusb_device **devs;
-	int r;
-	ssize_t cnt;
-
-	r = libusb_init(NULL);
-	if (r < 0)
-		return r;
-
-	cnt = libusb_get_device_list(NULL, &devs);
-	if (cnt < 0)
-		return (int) cnt;
-
-	print_devs(devs);
-	libusb_free_device_list(devs, 1);
-
-	libusb_exit(NULL);
-	return 0;
-}
-
diff --git a/third_party/libusb/libusb-1.0.pc.in b/third_party/libusb/libusb-1.0.pc.in
deleted file mode 100644
index 81b56ec..0000000
--- a/third_party/libusb/libusb-1.0.pc.in
+++ /dev/null
@@ -1,12 +0,0 @@
-prefix=@prefix@
-exec_prefix=@exec_prefix@
-libdir=@libdir@
-includedir=@includedir@
-
-Name: libusb-1.0
-Description: C API for USB device access from Linux, Mac OS X and Windows userspace
-Version: @VERSION@
-Libs: -L${libdir} -lusb-1.0
-Libs.private: @PC_LIBS_PRIVATE@
-Cflags: -I${includedir}/libusb-1.0
-
diff --git a/third_party/libusb/libusb.gyp b/third_party/libusb/libusb.gyp
deleted file mode 100644
index b57609c..0000000
--- a/third_party/libusb/libusb.gyp
+++ /dev/null
@@ -1,63 +0,0 @@
-# Copyright (c) 2012 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-{
-  'targets': [
-    {
-      'target_name': 'libusb',
-      'type': '<(library)',
-      'sources': [
-        'libusb/core.c',
-        'libusb/descriptor.c',
-        'libusb/io.c',
-        'libusb/sync.c',
-      ],
-      'include_dirs': [
-        '.',
-        'libusb',
-        'libusb/os',
-      ],
-      'conditions': [
-        [ 'OS == "linux"', {
-          'sources': [
-            'libusb/os/linux_usbfs.c',
-            'libusb/os/threads_posix.c',
-          ],
-          'defines': [
-            'HAVE_POLL_H=1',
-            'HAVE_SYS_TIME_H=1',
-            'OS_LINUX=1',
-            'POLL_NFDS_TYPE=nfds_t',
-            'THREADS_POSIX=1',
-          ],
-        }],
-        [ 'OS == "win"', {
-          'sources': [
-            'libusb/os/windows_usb.c',
-            'libusb/os/threads_windows.c',
-          ],
-          'include_dirs!': [
-            '.',
-          ],
-          'include_dirs': [
-            'msvc',
-          ],
-        }],
-        [ 'OS == "mac"', {
-          'sources': [
-            'libusb/os/darwin_usb.c',
-            'libusb/os/threads_posix.c',
-          ],
-          'defines': [
-            'HAVE_POLL_H=1',
-            'HAVE_SYS_TIME_H=1',
-            'OS_DARWIN=1',
-            'POLL_NFDS_TYPE=nfds_t',
-            'THREADS_POSIX=1',
-          ],
-        }],
-      ],
-    },
-  ],
-}
diff --git a/third_party/libusb/libusb/Makefile.am b/third_party/libusb/libusb/Makefile.am
deleted file mode 100644
index 22661dcc..0000000
--- a/third_party/libusb/libusb/Makefile.am
+++ /dev/null
@@ -1,40 +0,0 @@
-lib_LTLIBRARIES = libusb-1.0.la
-
-LINUX_USBFS_SRC = os/linux_usbfs.c
-DARWIN_USB_SRC = os/darwin_usb.c
-WINDOWS_USB_SRC = os/poll_windows.c os/windows_usb.c libusb-1.0.rc
-
-EXTRA_DIST = $(LINUX_USBFS_SRC) $(DARWIN_USB_SRC) $(WINDOWS_USB_SRC) \
-	os/threads_posix.c os/threads_windows.c
-
-if OS_LINUX
-OS_SRC = $(LINUX_USBFS_SRC)
-endif
-
-if OS_DARWIN
-OS_SRC = $(DARWIN_USB_SRC)
-AM_CFLAGS_EXT = -no-cpp-precomp
-endif
-
-if OS_WINDOWS
-OS_SRC = $(WINDOWS_USB_SRC)
-
-.rc.lo:
-	$(LIBTOOL) $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(RC) $(RCFLAGS) -i $< -o $@
-endif
-
-if THREADS_POSIX
-THREADS_SRC = os/threads_posix.h os/threads_posix.c
-else
-THREADS_SRC = os/threads_windows.h os/threads_windows.c
-endif
-
-libusb_1_0_la_CFLAGS = $(VISIBILITY_CFLAGS) $(AM_CFLAGS) $(THREAD_CFLAGS)
-libusb_1_0_la_LDFLAGS = $(LTLDFLAGS)
-libusb_1_0_la_SOURCES = libusbi.h core.c descriptor.c io.c sync.c $(OS_SRC) \
-	os/linux_usbfs.h os/darwin_usb.h os/windows_usb.h \
-	$(THREADS_SRC) \
-	os/poll_posix.h os/poll_windows.h
-
-hdrdir = $(includedir)/libusb-1.0
-hdr_HEADERS = libusb.h
diff --git a/third_party/libusb/libusb/core.c b/third_party/libusb/libusb/core.c
deleted file mode 100644
index a91c77b..0000000
--- a/third_party/libusb/libusb/core.c
+++ /dev/null
@@ -1,1781 +0,0 @@
-/*
- * Core functions for libusb
- * Copyright (C) 2007-2008 Daniel Drake <dsd@gentoo.org>
- * Copyright (c) 2001 Johannes Erdfelt <johannes@erdfelt.com>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#include <config.h>
-
-#include <errno.h>
-#include <stdarg.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/types.h>
-
-#include "libusbi.h"
-
-#if defined(OS_LINUX)
-const struct usbi_os_backend * const usbi_backend = &linux_usbfs_backend;
-#elif defined(OS_DARWIN)
-const struct usbi_os_backend * const usbi_backend = &darwin_backend;
-#elif defined(OS_WINDOWS)
-const struct usbi_os_backend * const usbi_backend = &windows_backend;
-#else
-#error "Unsupported OS"
-#endif
-
-struct libusb_context *usbi_default_context = NULL;
-static int default_context_refcnt = 0;
-static usbi_mutex_static_t default_context_lock = USBI_MUTEX_INITIALIZER;
-
-/**
- * \mainpage libusb-1.0 API Reference
- *
- * \section intro Introduction
- *
- * libusb is an open source library that allows you to communicate with USB
- * devices from userspace. For more info, see the
- * <a href="http://libusb.sourceforge.net">libusb homepage</a>.
- *
- * This documentation is aimed at application developers wishing to
- * communicate with USB peripherals from their own software. After reviewing
- * this documentation, feedback and questions can be sent to the
- * <a href="http://sourceforge.net/mail/?group_id=1674">libusb-devel mailing
- * list</a>.
- *
- * This documentation assumes knowledge of how to operate USB devices from
- * a software standpoint (descriptors, configurations, interfaces, endpoints,
- * control/bulk/interrupt/isochronous transfers, etc). Full information
- * can be found in the <a href="http://www.usb.org/developers/docs/">USB 2.0
- * Specification</a> which is available for free download. You can probably
- * find less verbose introductions by searching the web.
- *
- * \section features Library features
- *
- * - All transfer types supported (control/bulk/interrupt/isochronous)
- * - 2 transfer interfaces:
- *    -# Synchronous (simple)
- *    -# Asynchronous (more complicated, but more powerful)
- * - Thread safe (although the asynchronous interface means that you
- *   usually won't need to thread)
- * - Lightweight with lean API
- * - Compatible with libusb-0.1 through the libusb-compat-0.1 translation layer
- *
- * \section gettingstarted Getting Started
- *
- * To begin reading the API documentation, start with the Modules page which
- * links to the different categories of libusb's functionality.
- *
- * One decision you will have to make is whether to use the synchronous
- * or the asynchronous data transfer interface. The \ref io documentation
- * provides some insight into this topic.
- *
- * Some example programs can be found in the libusb source distribution under
- * the "examples" subdirectory. The libusb homepage includes a list of
- * real-life project examples which use libusb.
- *
- * \section errorhandling Error handling
- *
- * libusb functions typically return 0 on success or a negative error code
- * on failure. These negative error codes relate to LIBUSB_ERROR constants
- * which are listed on the \ref misc "miscellaneous" documentation page.
- *
- * \section msglog Debug message logging
- *
- * libusb does not log any messages by default. Your application is therefore
- * free to close stdout/stderr and those descriptors may be reused without
- * worry.
- *
- * The libusb_set_debug() function can be used to enable stdout/stderr logging
- * of certain messages. Under standard configuration, libusb doesn't really
- * log much at all, so you are advised to use this function to enable all
- * error/warning/informational messages. It will help you debug problems with
- * your software.
- *
- * The logged messages are unstructured. There is no one-to-one correspondence
- * between messages being logged and success or failure return codes from
- * libusb functions. There is no format to the messages, so you should not
- * try to capture or parse them. They are not and will not be localized.
- * These messages are not suitable for being passed to your application user;
- * instead, you should interpret the error codes returned from libusb functions
- * and provide appropriate notification to the user. The messages are simply
- * there to aid you as a programmer, and if you're confused because you're
- * getting a strange error code from a libusb function, enabling message
- * logging may give you a suitable explanation.
- *
- * The LIBUSB_DEBUG environment variable can be used to enable message logging
- * at run-time. This environment variable should be set to a number, which is
- * interpreted the same as the libusb_set_debug() parameter. When this
- * environment variable is set, the message logging verbosity level is fixed
- * and libusb_set_debug() effectively does nothing.
- *
- * libusb can be compiled without any logging functions, useful for embedded
- * systems. In this case, libusb_set_debug() and the LIBUSB_DEBUG environment
- * variable have no effects.
- *
- * libusb can also be compiled with verbose debugging messages. When the
- * library is compiled in this way, all messages of all verbosities are always
- * logged.  libusb_set_debug() and the LIBUSB_DEBUG environment variable have
- * no effects.
- *
- * \section remarks Other remarks
- *
- * libusb does have imperfections. The \ref caveats "caveats" page attempts
- * to document these.
- */
-
-/**
- * \page caveats Caveats
- *
- * \section devresets Device resets
- *
- * The libusb_reset_device() function allows you to reset a device. If your
- * program has to call such a function, it should obviously be aware that
- * the reset will cause device state to change (e.g. register values may be
- * reset).
- *
- * The problem is that any other program could reset the device your program
- * is working with, at any time. libusb does not offer a mechanism to inform
- * you when this has happened, so if someone else resets your device it will
- * not be clear to your own program why the device state has changed.
- *
- * Ultimately, this is a limitation of writing drivers in userspace.
- * Separation from the USB stack in the underlying kernel makes it difficult
- * for the operating system to deliver such notifications to your program.
- * The Linux kernel USB stack allows such reset notifications to be delivered
- * to in-kernel USB drivers, but it is not clear how such notifications could
- * be delivered to second-class drivers that live in userspace.
- *
- * \section blockonly Blocking-only functionality
- *
- * The functionality listed below is only available through synchronous,
- * blocking functions. There are no asynchronous/non-blocking alternatives,
- * and no clear ways of implementing these.
- *
- * - Configuration activation (libusb_set_configuration())
- * - Interface/alternate setting activation (libusb_set_interface_alt_setting())
- * - Releasing of interfaces (libusb_release_interface())
- * - Clearing of halt/stall condition (libusb_clear_halt())
- * - Device resets (libusb_reset_device())
- *
- * \section nohotplug No hotplugging
- *
- * libusb-1.0 lacks functionality for providing notifications of when devices
- * are added or removed. This functionality is planned to be implemented
- * for libusb-1.1.
- *
- * That said, there is basic disconnection handling for open device handles:
- *  - If there are ongoing transfers, libusb's handle_events loop will detect
- *    disconnections and complete ongoing transfers with the
- *    LIBUSB_TRANSFER_NO_DEVICE status code.
- *  - Many functions such as libusb_set_configuration() return the special
- *    LIBUSB_ERROR_NO_DEVICE error code when the device has been disconnected.
- *
- * \section configsel Configuration selection and handling
- *
- * When libusb presents a device handle to an application, there is a chance
- * that the corresponding device may be in unconfigured state. For devices
- * with multiple configurations, there is also a chance that the configuration
- * currently selected is not the one that the application wants to use.
- *
- * The obvious solution is to add a call to libusb_set_configuration() early
- * on during your device initialization routines, but there are caveats to
- * be aware of:
- * -# If the device is already in the desired configuration, calling
- *    libusb_set_configuration() using the same configuration value will cause
- *    a lightweight device reset. This may not be desirable behaviour.
- * -# libusb will be unable to change configuration if the device is in
- *    another configuration and other programs or drivers have claimed
- *    interfaces under that configuration.
- * -# In the case where the desired configuration is already active, libusb
- *    may not even be able to perform a lightweight device reset. For example,
- *    take my USB keyboard with fingerprint reader: I'm interested in driving
- *    the fingerprint reader interface through libusb, but the kernel's
- *    USB-HID driver will almost always have claimed the keyboard interface.
- *    Because the kernel has claimed an interface, it is not even possible to
- *    perform the lightweight device reset, so libusb_set_configuration() will
- *    fail. (Luckily the device in question only has a single configuration.)
- *
- * One solution to some of the above problems is to consider the currently
- * active configuration. If the configuration we want is already active, then
- * we don't have to select any configuration:
-\code
-cfg = libusb_get_configuration(dev);
-if (cfg != desired)
-	libusb_set_configuration(dev, desired);
-\endcode
- *
- * This is probably suitable for most scenarios, but is inherently racy:
- * another application or driver may change the selected configuration
- * <em>after</em> the libusb_get_configuration() call.
- *
- * Even in cases where libusb_set_configuration() succeeds, consider that other
- * applications or drivers may change configuration after your application
- * calls libusb_set_configuration().
- *
- * One possible way to lock your device into a specific configuration is as
- * follows:
- * -# Set the desired configuration (or use the logic above to realise that
- *    it is already in the desired configuration)
- * -# Claim the interface that you wish to use
- * -# Check that the currently active configuration is the one that you want
- *    to use.
- *
- * The above method works because once an interface is claimed, no application
- * or driver is able to select another configuration.
- *
- * \section earlycomp Early transfer completion
- *
- * NOTE: This section is currently Linux-centric. I am not sure if any of these
- * considerations apply to Darwin or other platforms.
- *
- * When a transfer completes early (i.e. when less data is received/sent in
- * any one packet than the transfer buffer allows for) then libusb is designed
- * to terminate the transfer immediately, not transferring or receiving any
- * more data unless other transfers have been queued by the user.
- *
- * On legacy platforms, libusb is unable to do this in all situations. After
- * the incomplete packet occurs, "surplus" data may be transferred. Prior to
- * libusb v1.0.2, this information was lost (and for device-to-host transfers,
- * the corresponding data was discarded). As of libusb v1.0.3, this information
- * is kept (the data length of the transfer is updated) and, for device-to-host
- * transfers, any surplus data was added to the buffer. Still, this is not
- * a nice solution because it loses the information about the end of the short
- * packet, and the user probably wanted that surplus data to arrive in the next
- * logical transfer.
- *
- * A previous workaround was to only ever submit transfers of size 16kb or
- * less.
- *
- * As of libusb v1.0.4 and Linux v2.6.32, this is fixed. A technical
- * explanation of this issue follows.
- *
- * When you ask libusb to submit a bulk transfer larger than 16kb in size,
- * libusb breaks it up into a number of smaller subtransfers. This is because
- * the usbfs kernel interface only accepts transfers of up to 16kb in size.
- * The subtransfers are submitted all at once so that the kernel can queue
- * them at the hardware level, therefore maximizing bus throughput.
- *
- * On legacy platforms, this caused problems when transfers completed early.
- * Upon this event, the kernel would terminate all further packets in that
- * subtransfer (but not any following ones). libusb would note this event and
- * immediately cancel any following subtransfers that had been queued,
- * but often libusb was not fast enough, and the following subtransfers had
- * started before libusb got around to cancelling them.
- *
- * Thanks to an API extension to usbfs, this is fixed with recent kernel and
- * libusb releases. The solution was to allow libusb to communicate to the
- * kernel where boundaries occur between logical libusb-level transfers. When
- * a short transfer (or other error) occurs, the kernel will cancel all the
- * subtransfers until the boundary without allowing those transfers to start.
- */
-
-/**
- * \page contexts Contexts
- *
- * It is possible that libusb may be used simultaneously from two independent
- * libraries linked into the same executable. For example, if your application
- * has a plugin-like system which allows the user to dynamically load a range
- * of modules into your program, it is feasible that two independently
- * developed modules may both use libusb.
- *
- * libusb is written to allow for these multiple user scenarios. The two
- * "instances" of libusb will not interfere: libusb_set_debug() calls
- * from one user will not affect the same settings for other users, other
- * users can continue using libusb after one of them calls libusb_exit(), etc.
- *
- * This is made possible through libusb's <em>context</em> concept. When you
- * call libusb_init(), you are (optionally) given a context. You can then pass
- * this context pointer back into future libusb functions.
- *
- * In order to keep things simple for more simplistic applications, it is
- * legal to pass NULL to all functions requiring a context pointer (as long as
- * you're sure no other code will attempt to use libusb from the same process).
- * When you pass NULL, the default context will be used. The default context
- * is created the first time a process calls libusb_init() when no other
- * context is alive. Contexts are destroyed during libusb_exit().
- *
- * The default context is reference-counted and can be shared. That means that
- * if libusb_init(NULL) is called twice within the same process, the two
- * users end up sharing the same context. The deinitialization and freeing of
- * the default context will only happen when the last user calls libusb_exit().
- * In other words, the default context is created and initialized when its
- * reference count goes from 0 to 1, and is deinitialized and destroyed when
- * its reference count goes from 1 to 0.
- *
- * You may be wondering why only a subset of libusb functions require a
- * context pointer in their function definition. Internally, libusb stores
- * context pointers in other objects (e.g. libusb_device instances) and hence
- * can infer the context from those objects.
- */
-
-/**
- * @defgroup lib Library initialization/deinitialization
- * This page details how to initialize and deinitialize libusb. Initialization
- * must be performed before using any libusb functionality, and similarly you
- * must not call any libusb functions after deinitialization.
- */
-
-/**
- * @defgroup dev Device handling and enumeration
- * The functionality documented below is designed to help with the following
- * operations:
- * - Enumerating the USB devices currently attached to the system
- * - Choosing a device to operate from your software
- * - Opening and closing the chosen device
- *
- * \section nutshell In a nutshell...
- *
- * The description below really makes things sound more complicated than they
- * actually are. The following sequence of function calls will be suitable
- * for almost all scenarios and does not require you to have such a deep
- * understanding of the resource management issues:
- * \code
-// discover devices
-libusb_device **list;
-libusb_device *found = NULL;
-ssize_t cnt = libusb_get_device_list(NULL, &list);
-ssize_t i = 0;
-int err = 0;
-if (cnt < 0)
-	error();
-
-for (i = 0; i < cnt; i++) {
-	libusb_device *device = list[i];
-	if (is_interesting(device)) {
-		found = device;
-		break;
-	}
-}
-
-if (found) {
-	libusb_device_handle *handle;
-
-	err = libusb_open(found, &handle);
-	if (err)
-		error();
-	// etc
-}
-
-libusb_free_device_list(list, 1);
-\endcode
- *
- * The two important points:
- * - You asked libusb_free_device_list() to unreference the devices (2nd
- *   parameter)
- * - You opened the device before freeing the list and unreferencing the
- *   devices
- *
- * If you ended up with a handle, you can now proceed to perform I/O on the
- * device.
- *
- * \section devshandles Devices and device handles
- * libusb has a concept of a USB device, represented by the
- * \ref libusb_device opaque type. A device represents a USB device that
- * is currently or was previously connected to the system. Using a reference
- * to a device, you can determine certain information about the device (e.g.
- * you can read the descriptor data).
- *
- * The libusb_get_device_list() function can be used to obtain a list of
- * devices currently connected to the system. This is known as device
- * discovery.
- *
- * Just because you have a reference to a device does not mean it is
- * necessarily usable. The device may have been unplugged, you may not have
- * permission to operate such device, or another program or driver may be
- * using the device.
- *
- * When you've found a device that you'd like to operate, you must ask
- * libusb to open the device using the libusb_open() function. Assuming
- * success, libusb then returns you a <em>device handle</em>
- * (a \ref libusb_device_handle pointer). All "real" I/O operations then
- * operate on the handle rather than the original device pointer.
- *
- * \section devref Device discovery and reference counting
- *
- * Device discovery (i.e. calling libusb_get_device_list()) returns a
- * freshly-allocated list of devices. The list itself must be freed when
- * you are done with it. libusb also needs to know when it is OK to free
- * the contents of the list - the devices themselves.
- *
- * To handle these issues, libusb provides you with two separate items:
- * - A function to free the list itself
- * - A reference counting system for the devices inside
- *
- * New devices presented by the libusb_get_device_list() function all have a
- * reference count of 1. You can increase and decrease reference count using
- * libusb_ref_device() and libusb_unref_device(). A device is destroyed when
- * its reference count reaches 0.
- *
- * With the above information in mind, the process of opening a device can
- * be viewed as follows:
- * -# Discover devices using libusb_get_device_list().
- * -# Choose the device that you want to operate, and call libusb_open().
- * -# Unref all devices in the discovered device list.
- * -# Free the discovered device list.
- *
- * The order is important - you must not unreference the device before
- * attempting to open it, because unreferencing it may destroy the device.
- *
- * For convenience, the libusb_free_device_list() function includes a
- * parameter to optionally unreference all the devices in the list before
- * freeing the list itself. This combines steps 3 and 4 above.
- *
- * As an implementation detail, libusb_open() actually adds a reference to
- * the device in question. This is because the device remains available
- * through the handle via libusb_get_device(). The reference is deleted during
- * libusb_close().
- */
-
-/** @defgroup misc Miscellaneous */
-
-/* we traverse usbfs without knowing how many devices we are going to find.
- * so we create this discovered_devs model which is similar to a linked-list
- * which grows when required. it can be freed once discovery has completed,
- * eliminating the need for a list node in the libusb_device structure
- * itself. */
-#define DISCOVERED_DEVICES_SIZE_STEP 8
-
-static struct discovered_devs *discovered_devs_alloc(void)
-{
-	struct discovered_devs *ret =
-		malloc(sizeof(*ret) + (sizeof(void *) * DISCOVERED_DEVICES_SIZE_STEP));
-
-	if (ret) {
-		ret->len = 0;
-		ret->capacity = DISCOVERED_DEVICES_SIZE_STEP;
-	}
-	return ret;
-}
-
-/* append a device to the discovered devices collection. may realloc itself,
- * returning new discdevs. returns NULL on realloc failure. */
-struct discovered_devs *discovered_devs_append(
-	struct discovered_devs *discdevs, struct libusb_device *dev)
-{
-	size_t len = discdevs->len;
-	size_t capacity;
-
-	/* if there is space, just append the device */
-	if (len < discdevs->capacity) {
-		discdevs->devices[len] = libusb_ref_device(dev);
-		discdevs->len++;
-		return discdevs;
-	}
-
-	/* exceeded capacity, need to grow */
-	usbi_dbg("need to increase capacity");
-	capacity = discdevs->capacity + DISCOVERED_DEVICES_SIZE_STEP;
-	discdevs = realloc(discdevs,
-		sizeof(*discdevs) + (sizeof(void *) * capacity));
-	if (discdevs) {
-		discdevs->capacity = capacity;
-		discdevs->devices[len] = libusb_ref_device(dev);
-		discdevs->len++;
-	}
-
-	return discdevs;
-}
-
-static void discovered_devs_free(struct discovered_devs *discdevs)
-{
-	size_t i;
-
-	for (i = 0; i < discdevs->len; i++)
-		libusb_unref_device(discdevs->devices[i]);
-
-	free(discdevs);
-}
-
-/* Allocate a new device with a specific session ID. The returned device has
- * a reference count of 1. */
-struct libusb_device *usbi_alloc_device(struct libusb_context *ctx,
-	unsigned long session_id)
-{
-	size_t priv_size = usbi_backend->device_priv_size;
-	struct libusb_device *dev = calloc(1, sizeof(*dev) + priv_size);
-	int r;
-
-	if (!dev)
-		return NULL;
-
-	r = usbi_mutex_init(&dev->lock, NULL);
-	if (r) {
-		free(dev);
-		return NULL;
-	}
-
-	dev->ctx = ctx;
-	dev->refcnt = 1;
-	dev->session_data = session_id;
-	dev->speed = LIBUSB_SPEED_UNKNOWN;
-	memset(&dev->os_priv, 0, priv_size);
-
-	usbi_mutex_lock(&ctx->usb_devs_lock);
-	list_add(&dev->list, &ctx->usb_devs);
-	usbi_mutex_unlock(&ctx->usb_devs_lock);
-	return dev;
-}
-
-/* Perform some final sanity checks on a newly discovered device. If this
- * function fails (negative return code), the device should not be added
- * to the discovered device list. */
-int usbi_sanitize_device(struct libusb_device *dev)
-{
-	int r;
-	unsigned char raw_desc[DEVICE_DESC_LENGTH];
-	uint8_t num_configurations;
-	int host_endian;
-
-	r = usbi_backend->get_device_descriptor(dev, raw_desc, &host_endian);
-	if (r < 0)
-		return r;
-
-	num_configurations = raw_desc[DEVICE_DESC_LENGTH - 1];
-	if (num_configurations > USB_MAXCONFIG) {
-		usbi_err(DEVICE_CTX(dev), "too many configurations");
-		return LIBUSB_ERROR_IO;
-	} else if (0 == num_configurations)
-		usbi_dbg("zero configurations, maybe an unauthorized device");
-
-	dev->num_configurations = num_configurations;
-	return 0;
-}
-
-/* Examine libusb's internal list of known devices, looking for one with
- * a specific session ID. Returns the matching device if it was found, and
- * NULL otherwise. */
-struct libusb_device *usbi_get_device_by_session_id(struct libusb_context *ctx,
-	unsigned long session_id)
-{
-	struct libusb_device *dev;
-	struct libusb_device *ret = NULL;
-
-	usbi_mutex_lock(&ctx->usb_devs_lock);
-	list_for_each_entry(dev, &ctx->usb_devs, list, struct libusb_device)
-		if (dev->session_data == session_id) {
-			ret = dev;
-			break;
-		}
-	usbi_mutex_unlock(&ctx->usb_devs_lock);
-
-	return ret;
-}
-
-/** @ingroup dev
- * Returns a list of USB devices currently attached to the system. This is
- * your entry point into finding a USB device to operate.
- *
- * You are expected to unreference all the devices when you are done with
- * them, and then free the list with libusb_free_device_list(). Note that
- * libusb_free_device_list() can unref all the devices for you. Be careful
- * not to unreference a device you are about to open until after you have
- * opened it.
- *
- * This return value of this function indicates the number of devices in
- * the resultant list. The list is actually one element larger, as it is
- * NULL-terminated.
- *
- * \param ctx the context to operate on, or NULL for the default context
- * \param list output location for a list of devices. Must be later freed with
- * libusb_free_device_list().
- * \returns The number of devices in the outputted list, or any
- * \ref libusb_error according to errors encountered by the backend.
- */
-ssize_t API_EXPORTED libusb_get_device_list(libusb_context *ctx,
-	libusb_device ***list)
-{
-	struct discovered_devs *discdevs = discovered_devs_alloc();
-	struct libusb_device **ret;
-	int r = 0;
-	ssize_t i, len;
-	USBI_GET_CONTEXT(ctx);
-	usbi_dbg("");
-
-	if (!discdevs)
-		return LIBUSB_ERROR_NO_MEM;
-
-	r = usbi_backend->get_device_list(ctx, &discdevs);
-	if (r < 0) {
-		len = r;
-		goto out;
-	}
-
-	/* convert discovered_devs into a list */
-	len = discdevs->len;
-	ret = malloc(sizeof(void *) * (len + 1));
-	if (!ret) {
-		len = LIBUSB_ERROR_NO_MEM;
-		goto out;
-	}
-
-	ret[len] = NULL;
-	for (i = 0; i < len; i++) {
-		struct libusb_device *dev = discdevs->devices[i];
-		ret[i] = libusb_ref_device(dev);
-	}
-	*list = ret;
-
-out:
-	discovered_devs_free(discdevs);
-	return len;
-}
-
-/** \ingroup dev
- * Frees a list of devices previously discovered using
- * libusb_get_device_list(). If the unref_devices parameter is set, the
- * reference count of each device in the list is decremented by 1.
- * \param list the list to free
- * \param unref_devices whether to unref the devices in the list
- */
-void API_EXPORTED libusb_free_device_list(libusb_device **list,
-	int unref_devices)
-{
-	if (!list)
-		return;
-
-	if (unref_devices) {
-		int i = 0;
-		struct libusb_device *dev;
-
-		while ((dev = list[i++]) != NULL)
-			libusb_unref_device(dev);
-	}
-	free(list);
-}
-
-/** \ingroup dev
- * Get the number of the bus that a device is connected to.
- * \param dev a device
- * \returns the bus number
- */
-uint8_t API_EXPORTED libusb_get_bus_number(libusb_device *dev)
-{
-	return dev->bus_number;
-}
-
-/** \ingroup dev
- * Get the address of the device on the bus it is connected to.
- * \param dev a device
- * \returns the device address
- */
-uint8_t API_EXPORTED libusb_get_device_address(libusb_device *dev)
-{
-	return dev->device_address;
-}
-
-/** \ingroup dev
- * Get the negotiated connection speed for a device.
- * \param dev a device
- * \returns a \ref libusb_speed code, where LIBUSB_SPEED_UNKNOWN means that
- * the OS doesn't know or doesn't support returning the negotiated speed.
- */
-int API_EXPORTED libusb_get_device_speed(libusb_device *dev)
-{
-	return dev->speed;
-}
-
-static const struct libusb_endpoint_descriptor *find_endpoint(
-	struct libusb_config_descriptor *config, unsigned char endpoint)
-{
-	int iface_idx;
-	for (iface_idx = 0; iface_idx < config->bNumInterfaces; iface_idx++) {
-		const struct libusb_interface *iface = &config->interface[iface_idx];
-		int altsetting_idx;
-
-		for (altsetting_idx = 0; altsetting_idx < iface->num_altsetting;
-				altsetting_idx++) {
-			const struct libusb_interface_descriptor *altsetting
-				= &iface->altsetting[altsetting_idx];
-			int ep_idx;
-
-			for (ep_idx = 0; ep_idx < altsetting->bNumEndpoints; ep_idx++) {
-				const struct libusb_endpoint_descriptor *ep =
-					&altsetting->endpoint[ep_idx];
-				if (ep->bEndpointAddress == endpoint)
-					return ep;
-			}
-		}
-	}
-	return NULL;
-}
-
-/** \ingroup dev
- * Convenience function to retrieve the wMaxPacketSize value for a particular
- * endpoint in the active device configuration.
- *
- * This function was originally intended to be of assistance when setting up
- * isochronous transfers, but a design mistake resulted in this function
- * instead. It simply returns the wMaxPacketSize value without considering
- * its contents. If you're dealing with isochronous transfers, you probably
- * want libusb_get_max_iso_packet_size() instead.
- *
- * \param dev a device
- * \param endpoint address of the endpoint in question
- * \returns the wMaxPacketSize value
- * \returns LIBUSB_ERROR_NOT_FOUND if the endpoint does not exist
- * \returns LIBUSB_ERROR_OTHER on other failure
- */
-int API_EXPORTED libusb_get_max_packet_size(libusb_device *dev,
-	unsigned char endpoint)
-{
-	struct libusb_config_descriptor *config;
-	const struct libusb_endpoint_descriptor *ep;
-	int r;
-
-	r = libusb_get_active_config_descriptor(dev, &config);
-	if (r < 0) {
-		usbi_err(DEVICE_CTX(dev),
-			"could not retrieve active config descriptor");
-		return LIBUSB_ERROR_OTHER;
-	}
-
-	ep = find_endpoint(config, endpoint);
-	if (!ep)
-		return LIBUSB_ERROR_NOT_FOUND;
-
-	r = ep->wMaxPacketSize;
-	libusb_free_config_descriptor(config);
-	return r;
-}
-
-/** \ingroup dev
- * Calculate the maximum packet size which a specific endpoint is capable is
- * sending or receiving in the duration of 1 microframe
- *
- * Only the active configution is examined. The calculation is based on the
- * wMaxPacketSize field in the endpoint descriptor as described in section
- * 9.6.6 in the USB 2.0 specifications.
- *
- * If acting on an isochronous or interrupt endpoint, this function will
- * multiply the value found in bits 0:10 by the number of transactions per
- * microframe (determined by bits 11:12). Otherwise, this function just
- * returns the numeric value found in bits 0:10.
- *
- * This function is useful for setting up isochronous transfers, for example
- * you might pass the return value from this function to
- * libusb_set_iso_packet_lengths() in order to set the length field of every
- * isochronous packet in a transfer.
- *
- * Since v1.0.3.
- *
- * \param dev a device
- * \param endpoint address of the endpoint in question
- * \returns the maximum packet size which can be sent/received on this endpoint
- * \returns LIBUSB_ERROR_NOT_FOUND if the endpoint does not exist
- * \returns LIBUSB_ERROR_OTHER on other failure
- */
-int API_EXPORTED libusb_get_max_iso_packet_size(libusb_device *dev,
-	unsigned char endpoint)
-{
-	struct libusb_config_descriptor *config;
-	const struct libusb_endpoint_descriptor *ep;
-	enum libusb_transfer_type ep_type;
-	uint16_t val;
-	int r;
-
-	r = libusb_get_active_config_descriptor(dev, &config);
-	if (r < 0) {
-		usbi_err(DEVICE_CTX(dev),
-			"could not retrieve active config descriptor");
-		return LIBUSB_ERROR_OTHER;
-	}
-
-	ep = find_endpoint(config, endpoint);
-	if (!ep)
-		return LIBUSB_ERROR_NOT_FOUND;
-
-	val = ep->wMaxPacketSize;
-	ep_type = ep->bmAttributes & 0x3;
-	libusb_free_config_descriptor(config);
-
-	r = val & 0x07ff;
-	if (ep_type == LIBUSB_TRANSFER_TYPE_ISOCHRONOUS
-			|| ep_type == LIBUSB_TRANSFER_TYPE_INTERRUPT)
-		r *= (1 + ((val >> 11) & 3));
-	return r;
-}
-
-/** \ingroup dev
- * Increment the reference count of a device.
- * \param dev the device to reference
- * \returns the same device
- */
-DEFAULT_VISIBILITY
-libusb_device * LIBUSB_CALL libusb_ref_device(libusb_device *dev)
-{
-	usbi_mutex_lock(&dev->lock);
-	dev->refcnt++;
-	usbi_mutex_unlock(&dev->lock);
-	return dev;
-}
-
-/** \ingroup dev
- * Decrement the reference count of a device. If the decrement operation
- * causes the reference count to reach zero, the device shall be destroyed.
- * \param dev the device to unreference
- */
-void API_EXPORTED libusb_unref_device(libusb_device *dev)
-{
-	int refcnt;
-
-	if (!dev)
-		return;
-
-	usbi_mutex_lock(&dev->lock);
-	refcnt = --dev->refcnt;
-	usbi_mutex_unlock(&dev->lock);
-
-	if (refcnt == 0) {
-		usbi_dbg("destroy device %d.%d", dev->bus_number, dev->device_address);
-
-		if (usbi_backend->destroy_device)
-			usbi_backend->destroy_device(dev);
-
-		usbi_mutex_lock(&dev->ctx->usb_devs_lock);
-		list_del(&dev->list);
-		usbi_mutex_unlock(&dev->ctx->usb_devs_lock);
-
-		usbi_mutex_destroy(&dev->lock);
-		free(dev);
-	}
-}
-
-/*
- * Interrupt the iteration of the event handling thread, so that it picks
- * up the new fd.
- */
-void usbi_fd_notification(struct libusb_context *ctx)
-{
-	unsigned char dummy = 1;
-	ssize_t r;
-
-	if (ctx == NULL)
-		return;
-
-	/* record that we are messing with poll fds */
-	usbi_mutex_lock(&ctx->pollfd_modify_lock);
-	ctx->pollfd_modify++;
-	usbi_mutex_unlock(&ctx->pollfd_modify_lock);
-
-	/* write some data on control pipe to interrupt event handlers */
-	r = usbi_write(ctx->ctrl_pipe[1], &dummy, sizeof(dummy));
-	if (r <= 0) {
-		usbi_warn(ctx, "internal signalling write failed");
-		usbi_mutex_lock(&ctx->pollfd_modify_lock);
-		ctx->pollfd_modify--;
-		usbi_mutex_unlock(&ctx->pollfd_modify_lock);
-		return;
-	}
-
-	/* take event handling lock */
-	libusb_lock_events(ctx);
-
-	/* read the dummy data */
-	r = usbi_read(ctx->ctrl_pipe[0], &dummy, sizeof(dummy));
-	if (r <= 0)
-		usbi_warn(ctx, "internal signalling read failed");
-
-	/* we're done with modifying poll fds */
-	usbi_mutex_lock(&ctx->pollfd_modify_lock);
-	ctx->pollfd_modify--;
-	usbi_mutex_unlock(&ctx->pollfd_modify_lock);
-
-	/* Release event handling lock and wake up event waiters */
-	libusb_unlock_events(ctx);
-}
-
-/** \ingroup dev
- * Open a device and obtain a device handle. A handle allows you to perform
- * I/O on the device in question.
- *
- * Internally, this function adds a reference to the device and makes it
- * available to you through libusb_get_device(). This reference is removed
- * during libusb_close().
- *
- * This is a non-blocking function; no requests are sent over the bus.
- *
- * \param dev the device to open
- * \param handle output location for the returned device handle pointer. Only
- * populated when the return code is 0.
- * \returns 0 on success
- * \returns LIBUSB_ERROR_NO_MEM on memory allocation failure
- * \returns LIBUSB_ERROR_ACCESS if the user has insufficient permissions
- * \returns LIBUSB_ERROR_NO_DEVICE if the device has been disconnected
- * \returns another LIBUSB_ERROR code on other failure
- */
-int API_EXPORTED libusb_open(libusb_device *dev,
-	libusb_device_handle **handle)
-{
-	struct libusb_context *ctx = DEVICE_CTX(dev);
-	struct libusb_device_handle *_handle;
-	size_t priv_size = usbi_backend->device_handle_priv_size;
-	int r;
-	usbi_dbg("open %d.%d", dev->bus_number, dev->device_address);
-
-	_handle = malloc(sizeof(*_handle) + priv_size);
-	if (!_handle)
-		return LIBUSB_ERROR_NO_MEM;
-
-	r = usbi_mutex_init(&_handle->lock, NULL);
-	if (r) {
-		free(_handle);
-		return LIBUSB_ERROR_OTHER;
-	}
-
-	_handle->dev = libusb_ref_device(dev);
-	_handle->claimed_interfaces = 0;
-	memset(&_handle->os_priv, 0, priv_size);
-
-	r = usbi_backend->open(_handle);
-	if (r < 0) {
-		usbi_dbg("open %d.%d returns %d", dev->bus_number, dev->device_address, r);
-		libusb_unref_device(dev);
-		usbi_mutex_destroy(&_handle->lock);
-		free(_handle);
-		return r;
-	}
-
-	usbi_mutex_lock(&ctx->open_devs_lock);
-	list_add(&_handle->list, &ctx->open_devs);
-	usbi_mutex_unlock(&ctx->open_devs_lock);
-	*handle = _handle;
-
-	/* At this point, we want to interrupt any existing event handlers so
-	 * that they realise the addition of the new device's poll fd. One
-	 * example when this is desirable is if the user is running a separate
-	 * dedicated libusb events handling thread, which is running with a long
-	 * or infinite timeout. We want to interrupt that iteration of the loop,
-	 * so that it picks up the new fd, and then continues. */
-	usbi_fd_notification(ctx);
-
-	return 0;
-}
-
-/** \ingroup dev
- * Convenience function for finding a device with a particular
- * <tt>idVendor</tt>/<tt>idProduct</tt> combination. This function is intended
- * for those scenarios where you are using libusb to knock up a quick test
- * application - it allows you to avoid calling libusb_get_device_list() and
- * worrying about traversing/freeing the list.
- *
- * This function has limitations and is hence not intended for use in real
- * applications: if multiple devices have the same IDs it will only
- * give you the first one, etc.
- *
- * \param ctx the context to operate on, or NULL for the default context
- * \param vendor_id the idVendor value to search for
- * \param product_id the idProduct value to search for
- * \returns a handle for the first found device, or NULL on error or if the
- * device could not be found. */
-DEFAULT_VISIBILITY
-libusb_device_handle * LIBUSB_CALL libusb_open_device_with_vid_pid(
-	libusb_context *ctx, uint16_t vendor_id, uint16_t product_id)
-{
-	struct libusb_device **devs;
-	struct libusb_device *found = NULL;
-	struct libusb_device *dev;
-	struct libusb_device_handle *handle = NULL;
-	size_t i = 0;
-	int r;
-
-	if (libusb_get_device_list(ctx, &devs) < 0)
-		return NULL;
-
-	while ((dev = devs[i++]) != NULL) {
-		struct libusb_device_descriptor desc;
-		r = libusb_get_device_descriptor(dev, &desc);
-		if (r < 0)
-			goto out;
-		if (desc.idVendor == vendor_id && desc.idProduct == product_id) {
-			found = dev;
-			break;
-		}
-	}
-
-	if (found) {
-		r = libusb_open(found, &handle);
-		if (r < 0)
-			handle = NULL;
-	}
-
-out:
-	libusb_free_device_list(devs, 1);
-	return handle;
-}
-
-static void do_close(struct libusb_context *ctx,
-	struct libusb_device_handle *dev_handle)
-{
-	struct usbi_transfer *itransfer;
-	struct usbi_transfer *tmp;
-
-	libusb_lock_events(ctx);
-
-	/* remove any transfers in flight that are for this device */
-	usbi_mutex_lock(&ctx->flying_transfers_lock);
-
-	/* safe iteration because transfers may be being deleted */
-	list_for_each_entry_safe(itransfer, tmp, &ctx->flying_transfers, list, struct usbi_transfer) {
-		struct libusb_transfer *transfer =
-		        USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-
-		if (transfer->dev_handle != dev_handle)
-			continue;
-
-		if (!(itransfer->flags & USBI_TRANSFER_DEVICE_DISAPPEARED)) {
-			usbi_err(ctx, "Device handle closed while transfer was still being processed, but the device is still connected as far as we know");
-
-			if (itransfer->flags & USBI_TRANSFER_CANCELLING)
-				usbi_warn(ctx, "A cancellation for an in-flight transfer hasn't completed but closing the device handle");
-			else
-				usbi_err(ctx, "A cancellation hasn't even been scheduled on the transfer for which the device is closing");
-		}
-
-		/* remove from the list of in-flight transfers and make sure
-		 * we don't accidentally use the device handle in the future
-		 * (or that such accesses will be easily caught and identified as a crash)
-		 */
-		usbi_mutex_lock(&itransfer->lock);
-		list_del(&itransfer->list);
-		transfer->dev_handle = NULL;
-		usbi_mutex_unlock(&itransfer->lock);
-
-		/* it is up to the user to free up the actual transfer struct.  this is
-		 * just making sure that we don't attempt to process the transfer after
-		 * the device handle is invalid
-		 */
-		usbi_dbg("Removed transfer %p from the in-flight list because device handle %p closed",
-			 transfer, dev_handle);
-	}
-	usbi_mutex_unlock(&ctx->flying_transfers_lock);
-
-	libusb_unlock_events(ctx);
-
-	usbi_mutex_lock(&ctx->open_devs_lock);
-	list_del(&dev_handle->list);
-	usbi_mutex_unlock(&ctx->open_devs_lock);
-
-	usbi_backend->close(dev_handle);
-	libusb_unref_device(dev_handle->dev);
-	usbi_mutex_destroy(&dev_handle->lock);
-	free(dev_handle);
-}
-
-/** \ingroup dev
- * Close a device handle. Should be called on all open handles before your
- * application exits.
- *
- * Internally, this function destroys the reference that was added by
- * libusb_open() on the given device.
- *
- * This is a non-blocking function; no requests are sent over the bus.
- *
- * \param dev_handle the handle to close
- */
-void API_EXPORTED libusb_close(libusb_device_handle *dev_handle)
-{
-	struct libusb_context *ctx;
-	unsigned char dummy = 1;
-	ssize_t r;
-
-	if (!dev_handle)
-		return;
-	usbi_dbg("");
-
-	ctx = HANDLE_CTX(dev_handle);
-
-	/* Similarly to libusb_open(), we want to interrupt all event handlers
-	 * at this point. More importantly, we want to perform the actual close of
-	 * the device while holding the event handling lock (preventing any other
-	 * thread from doing event handling) because we will be removing a file
-	 * descriptor from the polling loop. */
-
-	/* record that we are messing with poll fds */
-	usbi_mutex_lock(&ctx->pollfd_modify_lock);
-	ctx->pollfd_modify++;
-	usbi_mutex_unlock(&ctx->pollfd_modify_lock);
-
-	/* write some data on control pipe to interrupt event handlers */
-	r = usbi_write(ctx->ctrl_pipe[1], &dummy, sizeof(dummy));
-	if (r <= 0) {
-		usbi_warn(ctx, "internal signalling write failed, closing anyway");
-		do_close(ctx, dev_handle);
-		usbi_mutex_lock(&ctx->pollfd_modify_lock);
-		ctx->pollfd_modify--;
-		usbi_mutex_unlock(&ctx->pollfd_modify_lock);
-		return;
-	}
-
-	/* take event handling lock */
-	libusb_lock_events(ctx);
-
-	/* read the dummy data */
-	r = usbi_read(ctx->ctrl_pipe[0], &dummy, sizeof(dummy));
-	if (r <= 0)
-		usbi_warn(ctx, "internal signalling read failed, closing anyway");
-
-	/* Close the device */
-	do_close(ctx, dev_handle);
-
-	/* we're done with modifying poll fds */
-	usbi_mutex_lock(&ctx->pollfd_modify_lock);
-	ctx->pollfd_modify--;
-	usbi_mutex_unlock(&ctx->pollfd_modify_lock);
-
-	/* Release event handling lock and wake up event waiters */
-	libusb_unlock_events(ctx);
-}
-
-/** \ingroup dev
- * Get the underlying device for a handle. This function does not modify
- * the reference count of the returned device, so do not feel compelled to
- * unreference it when you are done.
- * \param dev_handle a device handle
- * \returns the underlying device
- */
-DEFAULT_VISIBILITY
-libusb_device * LIBUSB_CALL libusb_get_device(libusb_device_handle *dev_handle)
-{
-	return dev_handle->dev;
-}
-
-/** \ingroup dev
- * Determine the bConfigurationValue of the currently active configuration.
- *
- * You could formulate your own control request to obtain this information,
- * but this function has the advantage that it may be able to retrieve the
- * information from operating system caches (no I/O involved).
- *
- * If the OS does not cache this information, then this function will block
- * while a control transfer is submitted to retrieve the information.
- *
- * This function will return a value of 0 in the <tt>config</tt> output
- * parameter if the device is in unconfigured state.
- *
- * \param dev a device handle
- * \param config output location for the bConfigurationValue of the active
- * configuration (only valid for return code 0)
- * \returns 0 on success
- * \returns LIBUSB_ERROR_NO_DEVICE if the device has been disconnected
- * \returns another LIBUSB_ERROR code on other failure
- */
-int API_EXPORTED libusb_get_configuration(libusb_device_handle *dev,
-	int *config)
-{
-	int r = LIBUSB_ERROR_NOT_SUPPORTED;
-
-	usbi_dbg("");
-	if (usbi_backend->get_configuration)
-		r = usbi_backend->get_configuration(dev, config);
-
-	if (r == LIBUSB_ERROR_NOT_SUPPORTED) {
-		uint8_t tmp = 0;
-		usbi_dbg("falling back to control message");
-		r = libusb_control_transfer(dev, LIBUSB_ENDPOINT_IN,
-			LIBUSB_REQUEST_GET_CONFIGURATION, 0, 0, &tmp, 1, 1000);
-		if (r == 0) {
-			usbi_err(HANDLE_CTX(dev), "zero bytes returned in ctrl transfer?");
-			r = LIBUSB_ERROR_IO;
-		} else if (r == 1) {
-			r = 0;
-			*config = tmp;
-		} else {
-			usbi_dbg("control failed, error %d", r);
-		}
-	}
-
-	if (r == 0)
-		usbi_dbg("active config %d", *config);
-
-	return r;
-}
-
-/** \ingroup dev
- * Set the active configuration for a device.
- *
- * The operating system may or may not have already set an active
- * configuration on the device. It is up to your application to ensure the
- * correct configuration is selected before you attempt to claim interfaces
- * and perform other operations.
- *
- * If you call this function on a device already configured with the selected
- * configuration, then this function will act as a lightweight device reset:
- * it will issue a SET_CONFIGURATION request using the current configuration,
- * causing most USB-related device state to be reset (altsetting reset to zero,
- * endpoint halts cleared, toggles reset).
- *
- * You cannot change/reset configuration if your application has claimed
- * interfaces - you should free them with libusb_release_interface() first.
- * You cannot change/reset configuration if other applications or drivers have
- * claimed interfaces.
- *
- * A configuration value of -1 will put the device in unconfigured state.
- * The USB specifications state that a configuration value of 0 does this,
- * however buggy devices exist which actually have a configuration 0.
- *
- * You should always use this function rather than formulating your own
- * SET_CONFIGURATION control request. This is because the underlying operating
- * system needs to know when such changes happen.
- *
- * This is a blocking function.
- *
- * \param dev a device handle
- * \param configuration the bConfigurationValue of the configuration you
- * wish to activate, or -1 if you wish to put the device in unconfigured state
- * \returns 0 on success
- * \returns LIBUSB_ERROR_NOT_FOUND if the requested configuration does not exist
- * \returns LIBUSB_ERROR_BUSY if interfaces are currently claimed
- * \returns LIBUSB_ERROR_NO_DEVICE if the device has been disconnected
- * \returns another LIBUSB_ERROR code on other failure
- */
-int API_EXPORTED libusb_set_configuration(libusb_device_handle *dev,
-	int configuration)
-{
-	usbi_dbg("configuration %d", configuration);
-	return usbi_backend->set_configuration(dev, configuration);
-}
-
-/** \ingroup dev
- * Claim an interface on a given device handle. You must claim the interface
- * you wish to use before you can perform I/O on any of its endpoints.
- *
- * It is legal to attempt to claim an already-claimed interface, in which
- * case libusb just returns 0 without doing anything.
- *
- * Claiming of interfaces is a purely logical operation; it does not cause
- * any requests to be sent over the bus. Interface claiming is used to
- * instruct the underlying operating system that your application wishes
- * to take ownership of the interface.
- *
- * This is a non-blocking function.
- *
- * \param dev a device handle
- * \param interface_number the <tt>bInterfaceNumber</tt> of the interface you
- * wish to claim
- * \returns 0 on success
- * \returns LIBUSB_ERROR_NOT_FOUND if the requested interface does not exist
- * \returns LIBUSB_ERROR_BUSY if another program or driver has claimed the
- * interface
- * \returns LIBUSB_ERROR_NO_DEVICE if the device has been disconnected
- * \returns a LIBUSB_ERROR code on other failure
- */
-int API_EXPORTED libusb_claim_interface(libusb_device_handle *dev,
-	int interface_number)
-{
-	int r = 0;
-
-	usbi_dbg("interface %d", interface_number);
-	if (interface_number >= USB_MAXINTERFACES)
-		return LIBUSB_ERROR_INVALID_PARAM;
-
-	usbi_mutex_lock(&dev->lock);
-	if (dev->claimed_interfaces & (1 << interface_number))
-		goto out;
-
-	r = usbi_backend->claim_interface(dev, interface_number);
-	if (r == 0)
-		dev->claimed_interfaces |= 1 << interface_number;
-
-out:
-	usbi_mutex_unlock(&dev->lock);
-	return r;
-}
-
-/** \ingroup dev
- * Release an interface previously claimed with libusb_claim_interface(). You
- * should release all claimed interfaces before closing a device handle.
- *
- * This is a blocking function. A SET_INTERFACE control request will be sent
- * to the device, resetting interface state to the first alternate setting.
- *
- * \param dev a device handle
- * \param interface_number the <tt>bInterfaceNumber</tt> of the
- * previously-claimed interface
- * \returns 0 on success
- * \returns LIBUSB_ERROR_NOT_FOUND if the interface was not claimed
- * \returns LIBUSB_ERROR_NO_DEVICE if the device has been disconnected
- * \returns another LIBUSB_ERROR code on other failure
- */
-int API_EXPORTED libusb_release_interface(libusb_device_handle *dev,
-	int interface_number)
-{
-	int r;
-
-	usbi_dbg("interface %d", interface_number);
-	if (interface_number >= USB_MAXINTERFACES)
-		return LIBUSB_ERROR_INVALID_PARAM;
-
-	usbi_mutex_lock(&dev->lock);
-	if (!(dev->claimed_interfaces & (1 << interface_number))) {
-		r = LIBUSB_ERROR_NOT_FOUND;
-		goto out;
-	}
-
-	r = usbi_backend->release_interface(dev, interface_number);
-	if (r == 0)
-		dev->claimed_interfaces &= ~(1 << interface_number);
-
-out:
-	usbi_mutex_unlock(&dev->lock);
-	return r;
-}
-
-/** \ingroup dev
- * Activate an alternate setting for an interface. The interface must have
- * been previously claimed with libusb_claim_interface().
- *
- * You should always use this function rather than formulating your own
- * SET_INTERFACE control request. This is because the underlying operating
- * system needs to know when such changes happen.
- *
- * This is a blocking function.
- *
- * \param dev a device handle
- * \param interface_number the <tt>bInterfaceNumber</tt> of the
- * previously-claimed interface
- * \param alternate_setting the <tt>bAlternateSetting</tt> of the alternate
- * setting to activate
- * \returns 0 on success
- * \returns LIBUSB_ERROR_NOT_FOUND if the interface was not claimed, or the
- * requested alternate setting does not exist
- * \returns LIBUSB_ERROR_NO_DEVICE if the device has been disconnected
- * \returns another LIBUSB_ERROR code on other failure
- */
-int API_EXPORTED libusb_set_interface_alt_setting(libusb_device_handle *dev,
-	int interface_number, int alternate_setting)
-{
-	usbi_dbg("interface %d altsetting %d",
-		interface_number, alternate_setting);
-	if (interface_number >= USB_MAXINTERFACES)
-		return LIBUSB_ERROR_INVALID_PARAM;
-
-	usbi_mutex_lock(&dev->lock);
-	if (!(dev->claimed_interfaces & (1 << interface_number))) {
-		usbi_mutex_unlock(&dev->lock);
-		return LIBUSB_ERROR_NOT_FOUND;
-	}
-	usbi_mutex_unlock(&dev->lock);
-
-	return usbi_backend->set_interface_altsetting(dev, interface_number,
-		alternate_setting);
-}
-
-/** \ingroup dev
- * Clear the halt/stall condition for an endpoint. Endpoints with halt status
- * are unable to receive or transmit data until the halt condition is stalled.
- *
- * You should cancel all pending transfers before attempting to clear the halt
- * condition.
- *
- * This is a blocking function.
- *
- * \param dev a device handle
- * \param endpoint the endpoint to clear halt status
- * \returns 0 on success
- * \returns LIBUSB_ERROR_NOT_FOUND if the endpoint does not exist
- * \returns LIBUSB_ERROR_NO_DEVICE if the device has been disconnected
- * \returns another LIBUSB_ERROR code on other failure
- */
-int API_EXPORTED libusb_clear_halt(libusb_device_handle *dev,
-	unsigned char endpoint)
-{
-	usbi_dbg("endpoint %x", endpoint);
-	return usbi_backend->clear_halt(dev, endpoint);
-}
-
-/** \ingroup dev
- * Perform a USB port reset to reinitialize a device. The system will attempt
- * to restore the previous configuration and alternate settings after the
- * reset has completed.
- *
- * If the reset fails, the descriptors change, or the previous state cannot be
- * restored, the device will appear to be disconnected and reconnected. This
- * means that the device handle is no longer valid (you should close it) and
- * rediscover the device. A return code of LIBUSB_ERROR_NOT_FOUND indicates
- * when this is the case.
- *
- * This is a blocking function which usually incurs a noticeable delay.
- *
- * \param dev a handle of the device to reset
- * \returns 0 on success
- * \returns LIBUSB_ERROR_NOT_FOUND if re-enumeration is required, or if the
- * device has been disconnected
- * \returns another LIBUSB_ERROR code on other failure
- */
-int API_EXPORTED libusb_reset_device(libusb_device_handle *dev)
-{
-	usbi_dbg("");
-	return usbi_backend->reset_device(dev);
-}
-
-/** \ingroup dev
- * Determine if a kernel driver is active on an interface. If a kernel driver
- * is active, you cannot claim the interface, and libusb will be unable to
- * perform I/O.
- *
- * This functionality is not available on Windows.
- *
- * \param dev a device handle
- * \param interface_number the interface to check
- * \returns 0 if no kernel driver is active
- * \returns 1 if a kernel driver is active
- * \returns LIBUSB_ERROR_NO_DEVICE if the device has been disconnected
- * \returns LIBUSB_ERROR_NOT_SUPPORTED on platforms where the functionality
- * is not available
- * \returns another LIBUSB_ERROR code on other failure
- * \see libusb_detach_kernel_driver()
- */
-int API_EXPORTED libusb_kernel_driver_active(libusb_device_handle *dev,
-	int interface_number)
-{
-	usbi_dbg("interface %d", interface_number);
-	if (usbi_backend->kernel_driver_active)
-		return usbi_backend->kernel_driver_active(dev, interface_number);
-	else
-		return LIBUSB_ERROR_NOT_SUPPORTED;
-}
-
-/** \ingroup dev
- * Detach a kernel driver from an interface. If successful, you will then be
- * able to claim the interface and perform I/O.
- *
- * This functionality is not available on Darwin or Windows.
- *
- * \param dev a device handle
- * \param interface_number the interface to detach the driver from
- * \returns 0 on success
- * \returns LIBUSB_ERROR_NOT_FOUND if no kernel driver was active
- * \returns LIBUSB_ERROR_INVALID_PARAM if the interface does not exist
- * \returns LIBUSB_ERROR_NO_DEVICE if the device has been disconnected
- * \returns LIBUSB_ERROR_NOT_SUPPORTED on platforms where the functionality
- * is not available
- * \returns another LIBUSB_ERROR code on other failure
- * \see libusb_kernel_driver_active()
- */
-int API_EXPORTED libusb_detach_kernel_driver(libusb_device_handle *dev,
-	int interface_number)
-{
-	usbi_dbg("interface %d", interface_number);
-	if (usbi_backend->detach_kernel_driver)
-		return usbi_backend->detach_kernel_driver(dev, interface_number);
-	else
-		return LIBUSB_ERROR_NOT_SUPPORTED;
-}
-
-/** \ingroup dev
- * Re-attach an interface's kernel driver, which was previously detached
- * using libusb_detach_kernel_driver(). This call is only effective on
- * Linux and returns LIBUSB_ERROR_NOT_SUPPORTED on all other platforms.
- *
- * This functionality is not available on Darwin or Windows.
- *
- * \param dev a device handle
- * \param interface_number the interface to attach the driver from
- * \returns 0 on success
- * \returns LIBUSB_ERROR_NOT_FOUND if no kernel driver was active
- * \returns LIBUSB_ERROR_INVALID_PARAM if the interface does not exist
- * \returns LIBUSB_ERROR_NO_DEVICE if the device has been disconnected
- * \returns LIBUSB_ERROR_NOT_SUPPORTED on platforms where the functionality
- * is not available
- * \returns LIBUSB_ERROR_BUSY if the driver cannot be attached because the
- * interface is claimed by a program or driver
- * \returns another LIBUSB_ERROR code on other failure
- * \see libusb_kernel_driver_active()
- */
-int API_EXPORTED libusb_attach_kernel_driver(libusb_device_handle *dev,
-	int interface_number)
-{
-	usbi_dbg("interface %d", interface_number);
-	if (usbi_backend->attach_kernel_driver)
-		return usbi_backend->attach_kernel_driver(dev, interface_number);
-	else
-		return LIBUSB_ERROR_NOT_SUPPORTED;
-}
-
-/** \ingroup lib
- * Set message verbosity.
- *  - Level 0: no messages ever printed by the library (default)
- *  - Level 1: error messages are printed to stderr
- *  - Level 2: warning and error messages are printed to stderr
- *  - Level 3: informational messages are printed to stdout, warning and error
- *    messages are printed to stderr
- *
- * The default level is 0, which means no messages are ever printed. If you
- * choose to increase the message verbosity level, ensure that your
- * application does not close the stdout/stderr file descriptors.
- *
- * You are advised to set level 3. libusb is conservative with its message
- * logging and most of the time, will only log messages that explain error
- * conditions and other oddities. This will help you debug your software.
- *
- * If the LIBUSB_DEBUG environment variable was set when libusb was
- * initialized, this function does nothing: the message verbosity is fixed
- * to the value in the environment variable.
- *
- * If libusb was compiled without any message logging, this function does
- * nothing: you'll never get any messages.
- *
- * If libusb was compiled with verbose debug message logging, this function
- * does nothing: you'll always get messages from all levels.
- *
- * \param ctx the context to operate on, or NULL for the default context
- * \param level debug level to set
- */
-void API_EXPORTED libusb_set_debug(libusb_context *ctx, int level)
-{
-	USBI_GET_CONTEXT(ctx);
-	if (!ctx->debug_fixed)
-		ctx->debug = level;
-}
-
-/** \ingroup lib
- * Initialize libusb. This function must be called before calling any other
- * libusb function.
- *
- * If you do not provide an output location for a context pointer, a default
- * context will be created. If there was already a default context, it will
- * be reused (and nothing will be initialized/reinitialized).
- *
- * \param context Optional output location for context pointer.
- * Only valid on return code 0.
- * \returns 0 on success, or a LIBUSB_ERROR code on failure
- * \see contexts
- */
-int API_EXPORTED libusb_init(libusb_context **context)
-{
-	char *dbg = getenv("LIBUSB_DEBUG");
-	struct libusb_context *ctx;
-	int r;
-
-	usbi_mutex_static_lock(&default_context_lock);
-	if (!context && usbi_default_context) {
-		r = 0;
-		usbi_dbg("reusing default context");
-		default_context_refcnt++;
-		usbi_mutex_static_unlock(&default_context_lock);
-		return 0;
-	}
-
-	ctx = malloc(sizeof(*ctx));
-	if (!ctx) {
-		r = LIBUSB_ERROR_NO_MEM;
-		goto err_unlock;
-	}
-	memset(ctx, 0, sizeof(*ctx));
-
-	if (dbg) {
-		ctx->debug = atoi(dbg);
-		if (ctx->debug)
-			ctx->debug_fixed = 1;
-	}
-
-	usbi_dbg("");
-
-	if (usbi_backend->init) {
-		r = usbi_backend->init(ctx);
-		if (r)
-			goto err_free_ctx;
-	}
-
-	usbi_mutex_init(&ctx->usb_devs_lock, NULL);
-	usbi_mutex_init(&ctx->open_devs_lock, NULL);
-	list_init(&ctx->usb_devs);
-	list_init(&ctx->open_devs);
-
-	r = usbi_io_init(ctx);
-	if (r < 0) {
-		if (usbi_backend->exit)
-			usbi_backend->exit();
-		goto err_destroy_mutex;
-	}
-
-	if (context) {
-		*context = ctx;
-	} else if (!usbi_default_context) {
-		usbi_dbg("created default context");
-		usbi_default_context = ctx;
-		default_context_refcnt++;
-	}
-	usbi_mutex_static_unlock(&default_context_lock);
-
-	return 0;
-
-err_destroy_mutex:
-	usbi_mutex_destroy(&ctx->open_devs_lock);
-	usbi_mutex_destroy(&ctx->usb_devs_lock);
-err_free_ctx:
-	free(ctx);
-err_unlock:
-	usbi_mutex_static_unlock(&default_context_lock);
-	return r;
-}
-
-/** \ingroup lib
- * Deinitialize libusb. Should be called after closing all open devices and
- * before your application terminates.
- * \param ctx the context to deinitialize, or NULL for the default context
- */
-void API_EXPORTED libusb_exit(struct libusb_context *ctx)
-{
-	usbi_dbg("");
-	USBI_GET_CONTEXT(ctx);
-
-	/* if working with default context, only actually do the deinitialization
-	 * if we're the last user */
-	if (ctx == usbi_default_context) {
-		usbi_mutex_static_lock(&default_context_lock);
-		if (--default_context_refcnt > 0) {
-			usbi_dbg("not destroying default context");
-			usbi_mutex_static_unlock(&default_context_lock);
-			return;
-		}
-		usbi_dbg("destroying default context");
-		usbi_default_context = NULL;
-		usbi_mutex_static_unlock(&default_context_lock);
-	}
-
-	/* a little sanity check. doesn't bother with open_devs locking because
-	 * unless there is an application bug, nobody will be accessing this. */
-	if (!list_empty(&ctx->open_devs))
-		usbi_warn(ctx, "application left some devices open");
-
-	usbi_io_exit(ctx);
-	if (usbi_backend->exit)
-		usbi_backend->exit();
-
-	usbi_mutex_destroy(&ctx->open_devs_lock);
-	usbi_mutex_destroy(&ctx->usb_devs_lock);
-	free(ctx);
-}
-
-/** \ingroup misc
- * Check if the running library has a given capability.
- *
- * \param capability the \ref libusb_capability to check for
- * \returns 1 if the running library has the capability, 0 otherwise
- */
-int API_EXPORTED libusb_has_capability(uint32_t capability)
-{
-	switch (capability) {
-	case LIBUSB_CAN_GET_DEVICE_SPEED:
-		return 1;
-	default:
-		break;
-	}
-	return 0;
-}
-
-void usbi_log_v(struct libusb_context *ctx, enum usbi_log_level level,
-	const char *function, const char *format, va_list args)
-{
-	FILE *stream = stdout;
-	const char *prefix;
-
-#ifndef ENABLE_DEBUG_LOGGING
-	USBI_GET_CONTEXT(ctx);
-	if (!ctx->debug)
-		return;
-	if (level == LOG_LEVEL_WARNING && ctx->debug < 2)
-		return;
-	if (level == LOG_LEVEL_INFO && ctx->debug < 3)
-		return;
-#endif
-
-	switch (level) {
-	case LOG_LEVEL_INFO:
-		prefix = "info";
-		break;
-	case LOG_LEVEL_WARNING:
-		stream = stderr;
-		prefix = "warning";
-		break;
-	case LOG_LEVEL_ERROR:
-		stream = stderr;
-		prefix = "error";
-		break;
-	case LOG_LEVEL_DEBUG:
-		stream = stderr;
-		prefix = "debug";
-		break;
-	default:
-		stream = stderr;
-		prefix = "unknown";
-		break;
-	}
-
-	fprintf(stream, "libusb:%s [%s] ", prefix, function);
-
-	vfprintf(stream, format, args);
-
-	fprintf(stream, "\n");
-}
-
-void usbi_log(struct libusb_context *ctx, enum usbi_log_level level,
-	const char *function, const char *format, ...)
-{
-	va_list args;
-
-	va_start (args, format);
-	usbi_log_v(ctx, level, function, format, args);
-	va_end (args);
-}
-
-/** \ingroup misc
- * Returns a constant NULL-terminated string with the ASCII name of a libusb
- * error code. The caller must not free() the returned string.
- *
- * \param error_code The \ref libusb_error code to return the name of.
- * \returns The error name, or the string **UNKNOWN** if the value of
- * error_code is not a known error code.
- */
-DEFAULT_VISIBILITY const char * LIBUSB_CALL libusb_error_name(int error_code)
-{
-	enum libusb_error error = error_code;
-	switch (error) {
-	case LIBUSB_SUCCESS:
-		return "LIBUSB_SUCCESS";
-	case LIBUSB_ERROR_IO:
-		return "LIBUSB_ERROR_IO";
-	case LIBUSB_ERROR_INVALID_PARAM:
-		return "LIBUSB_ERROR_INVALID_PARAM";
-	case LIBUSB_ERROR_ACCESS:
-		return "LIBUSB_ERROR_ACCESS";
-	case LIBUSB_ERROR_NO_DEVICE:
-		return "LIBUSB_ERROR_NO_DEVICE";
-	case LIBUSB_ERROR_NOT_FOUND:
-		return "LIBUSB_ERROR_NOT_FOUND";
-	case LIBUSB_ERROR_BUSY:
-		return "LIBUSB_ERROR_BUSY";
-	case LIBUSB_ERROR_TIMEOUT:
-		return "LIBUSB_ERROR_TIMEOUT";
-	case LIBUSB_ERROR_OVERFLOW:
-		return "LIBUSB_ERROR_OVERFLOW";
-	case LIBUSB_ERROR_PIPE:
-		return "LIBUSB_ERROR_PIPE";
-	case LIBUSB_ERROR_INTERRUPTED:
-		return "LIBUSB_ERROR_INTERRUPTED";
-	case LIBUSB_ERROR_NO_MEM:
-		return "LIBUSB_ERROR_NO_MEM";
-	case LIBUSB_ERROR_NOT_SUPPORTED:
-		return "LIBUSB_ERROR_NOT_SUPPORTED";
-	case LIBUSB_ERROR_OTHER:
-		return "LIBUSB_ERROR_OTHER";
-	}
-	return "**UNKNOWN**";
-}
diff --git a/third_party/libusb/libusb/descriptor.c b/third_party/libusb/libusb/descriptor.c
deleted file mode 100644
index e358e9e..0000000
--- a/third_party/libusb/libusb/descriptor.c
+++ /dev/null
@@ -1,730 +0,0 @@
-/*
- * USB descriptor handling functions for libusb
- * Copyright (C) 2007 Daniel Drake <dsd@gentoo.org>
- * Copyright (c) 2001 Johannes Erdfelt <johannes@erdfelt.com>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#include <errno.h>
-#include <stdint.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include "libusbi.h"
-
-#define DESC_HEADER_LENGTH		2
-#define DEVICE_DESC_LENGTH		18
-#define CONFIG_DESC_LENGTH		9
-#define INTERFACE_DESC_LENGTH		9
-#define ENDPOINT_DESC_LENGTH		7
-#define ENDPOINT_AUDIO_DESC_LENGTH	9
-
-/** @defgroup desc USB descriptors
- * This page details how to examine the various standard USB descriptors
- * for detected devices
- */
-
-/* set host_endian if the w values are already in host endian format,
- * as opposed to bus endian. */
-int usbi_parse_descriptor(unsigned char *source, const char *descriptor,
-	void *dest, int host_endian)
-{
-	unsigned char *sp = source, *dp = dest;
-	uint16_t w;
-	const char *cp;
-
-	for (cp = descriptor; *cp; cp++) {
-		switch (*cp) {
-			case 'b':	/* 8-bit byte */
-				*dp++ = *sp++;
-				break;
-			case 'w':	/* 16-bit word, convert from little endian to CPU */
-				dp += ((uintptr_t)dp & 1);	/* Align to word boundary */
-
-				if (host_endian) {
-					memcpy(dp, sp, 2);
-				} else {
-					w = (sp[1] << 8) | sp[0];
-					*((uint16_t *)dp) = w;
-				}
-				sp += 2;
-				dp += 2;
-				break;
-		}
-	}
-
-	return (int) (sp - source);
-}
-
-static void clear_endpoint(struct libusb_endpoint_descriptor *endpoint)
-{
-	if (endpoint->extra)
-		free((unsigned char *) endpoint->extra);
-}
-
-static int parse_endpoint(struct libusb_context *ctx,
-	struct libusb_endpoint_descriptor *endpoint, unsigned char *buffer,
-	int size, int host_endian)
-{
-	struct usb_descriptor_header header;
-	unsigned char *extra;
-	unsigned char *begin;
-	int parsed = 0;
-	int len;
-
-	usbi_parse_descriptor(buffer, "bb", &header, 0);
-
-	/* Everything should be fine being passed into here, but we sanity */
-	/*  check JIC */
-	if (header.bLength > size) {
-		usbi_err(ctx, "ran out of descriptors parsing");
-		return -1;
-	}
-
-	if (header.bDescriptorType != LIBUSB_DT_ENDPOINT) {
-		usbi_err(ctx, "unexpected descriptor %x (expected %x)",
-			header.bDescriptorType, LIBUSB_DT_ENDPOINT);
-		return parsed;
-	}
-
-	if (header.bLength >= ENDPOINT_AUDIO_DESC_LENGTH)
-		usbi_parse_descriptor(buffer, "bbbbwbbb", endpoint, host_endian);
-	else if (header.bLength >= ENDPOINT_DESC_LENGTH)
-		usbi_parse_descriptor(buffer, "bbbbwb", endpoint, host_endian);
-
-	buffer += header.bLength;
-	size -= header.bLength;
-	parsed += header.bLength;
-
-	/* Skip over the rest of the Class Specific or Vendor Specific */
-	/*  descriptors */
-	begin = buffer;
-	while (size >= DESC_HEADER_LENGTH) {
-		usbi_parse_descriptor(buffer, "bb", &header, 0);
-
-		if (header.bLength < 2) {
-			usbi_err(ctx, "invalid descriptor length %d", header.bLength);
-			return -1;
-		}
-
-		/* If we find another "proper" descriptor then we're done  */
-		if ((header.bDescriptorType == LIBUSB_DT_ENDPOINT) ||
-				(header.bDescriptorType == LIBUSB_DT_INTERFACE) ||
-				(header.bDescriptorType == LIBUSB_DT_CONFIG) ||
-				(header.bDescriptorType == LIBUSB_DT_DEVICE))
-			break;
-
-		usbi_dbg("skipping descriptor %x", header.bDescriptorType);
-		buffer += header.bLength;
-		size -= header.bLength;
-		parsed += header.bLength;
-	}
-
-	/* Copy any unknown descriptors into a storage area for drivers */
-	/*  to later parse */
-	len = (int)(buffer - begin);
-	if (!len) {
-		endpoint->extra = NULL;
-		endpoint->extra_length = 0;
-		return parsed;
-	}
-
-	extra = malloc(len);
-	endpoint->extra = extra;
-	if (!extra) {
-		endpoint->extra_length = 0;
-		return LIBUSB_ERROR_NO_MEM;
-	}
-
-	memcpy(extra, begin, len);
-	endpoint->extra_length = len;
-
-	return parsed;
-}
-
-static void clear_interface(struct libusb_interface *usb_interface)
-{
-	int i;
-	int j;
-
-	if (usb_interface->altsetting) {
-		for (i = 0; i < usb_interface->num_altsetting; i++) {
-			struct libusb_interface_descriptor *ifp =
-				(struct libusb_interface_descriptor *)
-				usb_interface->altsetting + i;
-			if (ifp->extra)
-				free((void *) ifp->extra);
-			if (ifp->endpoint) {
-				for (j = 0; j < ifp->bNumEndpoints; j++)
-					clear_endpoint((struct libusb_endpoint_descriptor *)
-						ifp->endpoint + j);
-				free((void *) ifp->endpoint);
-			}
-		}
-		free((void *) usb_interface->altsetting);
-		usb_interface->altsetting = NULL;
-	}
-
-}
-
-static int parse_interface(libusb_context *ctx,
-	struct libusb_interface *usb_interface, unsigned char *buffer, int size,
-	int host_endian)
-{
-	int i;
-	int len;
-	int r;
-	int parsed = 0;
-	size_t tmp;
-	struct usb_descriptor_header header;
-	struct libusb_interface_descriptor *ifp;
-	unsigned char *begin;
-
-	usb_interface->num_altsetting = 0;
-
-	while (size >= INTERFACE_DESC_LENGTH) {
-		struct libusb_interface_descriptor *altsetting =
-			(struct libusb_interface_descriptor *) usb_interface->altsetting;
-		altsetting = realloc(altsetting,
-			sizeof(struct libusb_interface_descriptor) *
-			(usb_interface->num_altsetting + 1));
-		if (!altsetting) {
-			r = LIBUSB_ERROR_NO_MEM;
-			goto err;
-		}
-		usb_interface->altsetting = altsetting;
-
-		ifp = altsetting + usb_interface->num_altsetting;
-		usb_interface->num_altsetting++;
-		usbi_parse_descriptor(buffer, "bbbbbbbbb", ifp, 0);
-		ifp->extra = NULL;
-		ifp->extra_length = 0;
-		ifp->endpoint = NULL;
-
-		/* Skip over the interface */
-		buffer += ifp->bLength;
-		parsed += ifp->bLength;
-		size -= ifp->bLength;
-
-		begin = buffer;
-
-		/* Skip over any interface, class or vendor descriptors */
-		while (size >= DESC_HEADER_LENGTH) {
-			usbi_parse_descriptor(buffer, "bb", &header, 0);
-			if (header.bLength < 2) {
-				usbi_err(ctx, "invalid descriptor of length %d",
-					header.bLength);
-				r = LIBUSB_ERROR_IO;
-				goto err;
-			}
-
-			/* If we find another "proper" descriptor then we're done */
-			if ((header.bDescriptorType == LIBUSB_DT_INTERFACE) ||
-					(header.bDescriptorType == LIBUSB_DT_ENDPOINT) ||
-					(header.bDescriptorType == LIBUSB_DT_CONFIG) ||
-					(header.bDescriptorType == LIBUSB_DT_DEVICE))
-				break;
-
-			buffer += header.bLength;
-			parsed += header.bLength;
-			size -= header.bLength;
-		}
-
-		/* Copy any unknown descriptors into a storage area for */
-		/*  drivers to later parse */
-		len = (int)(buffer - begin);
-		if (len) {
-			ifp->extra = malloc(len);
-			if (!ifp->extra) {
-				r = LIBUSB_ERROR_NO_MEM;
-				goto err;
-			}
-			memcpy((unsigned char *) ifp->extra, begin, len);
-			ifp->extra_length = len;
-		}
-
-		/* Did we hit an unexpected descriptor? */
-		if (size >= DESC_HEADER_LENGTH) {
-			usbi_parse_descriptor(buffer, "bb", &header, 0);
-			if ((header.bDescriptorType == LIBUSB_DT_CONFIG) ||
-			    (header.bDescriptorType == LIBUSB_DT_DEVICE)) {
-				return parsed;
-			}
-		}
-
-		if (ifp->bNumEndpoints > USB_MAXENDPOINTS) {
-			usbi_err(ctx, "too many endpoints (%d)", ifp->bNumEndpoints);
-			r = LIBUSB_ERROR_IO;
-			goto err;
-		}
-
-		if (ifp->bNumEndpoints > 0) {
-			struct libusb_endpoint_descriptor *endpoint;
-			tmp = ifp->bNumEndpoints * sizeof(struct libusb_endpoint_descriptor);
-			endpoint = malloc(tmp);
-			ifp->endpoint = endpoint;
-			if (!endpoint) {
-				r = LIBUSB_ERROR_NO_MEM;
-				goto err;
-			}
-
-			memset(endpoint, 0, tmp);
-			for (i = 0; i < ifp->bNumEndpoints; i++) {
-				usbi_parse_descriptor(buffer, "bb", &header, 0);
-
-				if (header.bLength > size) {
-					usbi_err(ctx, "ran out of descriptors parsing");
-					r = LIBUSB_ERROR_IO;
-					goto err;
-				}
-
-				r = parse_endpoint(ctx, endpoint + i, buffer, size,
-					host_endian);
-				if (r < 0)
-					goto err;
-
-				buffer += r;
-				parsed += r;
-				size -= r;
-			}
-		}
-
-		/* We check to see if it's an alternate to this one */
-		ifp = (struct libusb_interface_descriptor *) buffer;
-		if (size < LIBUSB_DT_INTERFACE_SIZE ||
-				ifp->bDescriptorType != LIBUSB_DT_INTERFACE ||
-				!ifp->bAlternateSetting)
-			return parsed;
-	}
-
-	return parsed;
-err:
-	clear_interface(usb_interface);
-	return r;
-}
-
-static void clear_configuration(struct libusb_config_descriptor *config)
-{
-	if (config->interface) {
-		int i;
-		for (i = 0; i < config->bNumInterfaces; i++)
-			clear_interface((struct libusb_interface *)
-				config->interface + i);
-		free((void *) config->interface);
-	}
-	if (config->extra)
-		free((void *) config->extra);
-}
-
-static int parse_configuration(struct libusb_context *ctx,
-	struct libusb_config_descriptor *config, unsigned char *buffer,
-	int host_endian)
-{
-	int i;
-	int r;
-	int size;
-	size_t tmp;
-	struct usb_descriptor_header header;
-	struct libusb_interface *usb_interface;
-
-	usbi_parse_descriptor(buffer, "bbwbbbbb", config, host_endian);
-	size = config->wTotalLength;
-
-	if (config->bNumInterfaces > USB_MAXINTERFACES) {
-		usbi_err(ctx, "too many interfaces (%d)", config->bNumInterfaces);
-		return LIBUSB_ERROR_IO;
-	}
-
-	tmp = config->bNumInterfaces * sizeof(struct libusb_interface);
-	usb_interface = malloc(tmp);
-	config->interface = usb_interface;
-	if (!config->interface)
-		return LIBUSB_ERROR_NO_MEM;
-
-	memset(usb_interface, 0, tmp);
-	buffer += config->bLength;
-	size -= config->bLength;
-
-	config->extra = NULL;
-	config->extra_length = 0;
-
-	for (i = 0; i < config->bNumInterfaces; i++) {
-		int len;
-		unsigned char *begin;
-
-		/* Skip over the rest of the Class Specific or Vendor */
-		/*  Specific descriptors */
-		begin = buffer;
-		while (size >= DESC_HEADER_LENGTH) {
-			usbi_parse_descriptor(buffer, "bb", &header, 0);
-
-			if ((header.bLength > size) ||
-					(header.bLength < DESC_HEADER_LENGTH)) {
-				usbi_err(ctx, "invalid descriptor length of %d",
-					header.bLength);
-				r = LIBUSB_ERROR_IO;
-				goto err;
-			}
-
-			/* If we find another "proper" descriptor then we're done */
-			if ((header.bDescriptorType == LIBUSB_DT_ENDPOINT) ||
-					(header.bDescriptorType == LIBUSB_DT_INTERFACE) ||
-					(header.bDescriptorType == LIBUSB_DT_CONFIG) ||
-					(header.bDescriptorType == LIBUSB_DT_DEVICE))
-				break;
-
-			usbi_dbg("skipping descriptor 0x%x\n", header.bDescriptorType);
-			buffer += header.bLength;
-			size -= header.bLength;
-		}
-
-		/* Copy any unknown descriptors into a storage area for */
-		/*  drivers to later parse */
-		len = (int)(buffer - begin);
-		if (len) {
-			/* FIXME: We should realloc and append here */
-			if (!config->extra_length) {
-				config->extra = malloc(len);
-				if (!config->extra) {
-					r = LIBUSB_ERROR_NO_MEM;
-					goto err;
-				}
-
-				memcpy((unsigned char *) config->extra, begin, len);
-				config->extra_length = len;
-			}
-		}
-
-		r = parse_interface(ctx, usb_interface + i, buffer, size, host_endian);
-		if (r < 0)
-			goto err;
-
-		buffer += r;
-		size -= r;
-	}
-
-	return size;
-
-err:
-	clear_configuration(config);
-	return r;
-}
-
-/** \ingroup desc
- * Get the USB device descriptor for a given device.
- *
- * This is a non-blocking function; the device descriptor is cached in memory.
- *
- * \param dev the device
- * \param desc output location for the descriptor data
- * \returns 0 on success or a LIBUSB_ERROR code on failure
- */
-int API_EXPORTED libusb_get_device_descriptor(libusb_device *dev,
-	struct libusb_device_descriptor *desc)
-{
-	unsigned char raw_desc[DEVICE_DESC_LENGTH];
-	int host_endian = 0;
-	int r;
-
-	usbi_dbg("");
-	r = usbi_backend->get_device_descriptor(dev, raw_desc, &host_endian);
-	if (r < 0)
-		return r;
-
-	memcpy((unsigned char *) desc, raw_desc, sizeof(raw_desc));
-	if (!host_endian) {
-		desc->bcdUSB = libusb_le16_to_cpu(desc->bcdUSB);
-		desc->idVendor = libusb_le16_to_cpu(desc->idVendor);
-		desc->idProduct = libusb_le16_to_cpu(desc->idProduct);
-		desc->bcdDevice = libusb_le16_to_cpu(desc->bcdDevice);
-	}
-	return 0;
-}
-
-/** \ingroup desc
- * Get the USB configuration descriptor for the currently active configuration.
- * This is a non-blocking function which does not involve any requests being
- * sent to the device.
- *
- * \param dev a device
- * \param config output location for the USB configuration descriptor. Only
- * valid if 0 was returned. Must be freed with libusb_free_config_descriptor()
- * after use.
- * \returns 0 on success
- * \returns LIBUSB_ERROR_NOT_FOUND if the device is in unconfigured state
- * \returns another LIBUSB_ERROR code on error
- * \see libusb_get_config_descriptor
- */
-int API_EXPORTED libusb_get_active_config_descriptor(libusb_device *dev,
-	struct libusb_config_descriptor **config)
-{
-	struct libusb_config_descriptor *_config = malloc(sizeof(*_config));
-	unsigned char tmp[8];
-	unsigned char *buf = NULL;
-	int host_endian = 0;
-	int r;
-
-	usbi_dbg("");
-	if (!_config)
-		return LIBUSB_ERROR_NO_MEM;
-
-	r = usbi_backend->get_active_config_descriptor(dev, tmp, sizeof(tmp),
-		&host_endian);
-	if (r < 0)
-		goto err;
-
-	usbi_parse_descriptor(tmp, "bbw", _config, host_endian);
-	buf = malloc(_config->wTotalLength);
-	if (!buf) {
-		r = LIBUSB_ERROR_NO_MEM;
-		goto err;
-	}
-
-	r = usbi_backend->get_active_config_descriptor(dev, buf,
-		_config->wTotalLength, &host_endian);
-	if (r < 0)
-		goto err;
-
-	r = parse_configuration(dev->ctx, _config, buf, host_endian);
-	if (r < 0) {
-		usbi_err(dev->ctx, "parse_configuration failed with error %d", r);
-		goto err;
-	} else if (r > 0) {
-		usbi_warn(dev->ctx, "descriptor data still left");
-	}
-
-	free(buf);
-	*config = _config;
-	return 0;
-
-err:
-	free(_config);
-	if (buf)
-		free(buf);
-	return r;
-}
-
-/** \ingroup desc
- * Get a USB configuration descriptor based on its index.
- * This is a non-blocking function which does not involve any requests being
- * sent to the device.
- *
- * \param dev a device
- * \param config_index the index of the configuration you wish to retrieve
- * \param config output location for the USB configuration descriptor. Only
- * valid if 0 was returned. Must be freed with libusb_free_config_descriptor()
- * after use.
- * \returns 0 on success
- * \returns LIBUSB_ERROR_NOT_FOUND if the configuration does not exist
- * \returns another LIBUSB_ERROR code on error
- * \see libusb_get_active_config_descriptor()
- * \see libusb_get_config_descriptor_by_value()
- */
-int API_EXPORTED libusb_get_config_descriptor(libusb_device *dev,
-	uint8_t config_index, struct libusb_config_descriptor **config)
-{
-	struct libusb_config_descriptor *_config;
-	unsigned char tmp[8];
-	unsigned char *buf = NULL;
-	int host_endian = 0;
-	int r;
-
-	usbi_dbg("index %d", config_index);
-	if (config_index >= dev->num_configurations)
-		return LIBUSB_ERROR_NOT_FOUND;
-
-	_config = malloc(sizeof(*_config));
-	if (!_config)
-		return LIBUSB_ERROR_NO_MEM;
-
-	r = usbi_backend->get_config_descriptor(dev, config_index, tmp,
-		sizeof(tmp), &host_endian);
-	if (r < 0)
-		goto err;
-
-	usbi_parse_descriptor(tmp, "bbw", _config, host_endian);
-	buf = malloc(_config->wTotalLength);
-	if (!buf) {
-		r = LIBUSB_ERROR_NO_MEM;
-		goto err;
-	}
-
-	host_endian = 0;
-	r = usbi_backend->get_config_descriptor(dev, config_index, buf,
-		_config->wTotalLength, &host_endian);
-	if (r < 0)
-		goto err;
-
-	r = parse_configuration(dev->ctx, _config, buf, host_endian);
-	if (r < 0) {
-		usbi_err(dev->ctx, "parse_configuration failed with error %d", r);
-		goto err;
-	} else if (r > 0) {
-		usbi_warn(dev->ctx, "descriptor data still left");
-	}
-
-	free(buf);
-	*config = _config;
-	return 0;
-
-err:
-	free(_config);
-	if (buf)
-		free(buf);
-	return r;
-}
-
-/* iterate through all configurations, returning the index of the configuration
- * matching a specific bConfigurationValue in the idx output parameter, or -1
- * if the config was not found.
- * returns 0 or a LIBUSB_ERROR code
- */
-int usbi_get_config_index_by_value(struct libusb_device *dev,
-	uint8_t bConfigurationValue, int *idx)
-{
-	uint8_t i;
-
-	usbi_dbg("value %d", bConfigurationValue);
-	for (i = 0; i < dev->num_configurations; i++) {
-		unsigned char tmp[6];
-		int host_endian;
-		int r = usbi_backend->get_config_descriptor(dev, i, tmp, sizeof(tmp),
-			&host_endian);
-		if (r < 0)
-			return r;
-		if (tmp[5] == bConfigurationValue) {
-			*idx = i;
-			return 0;
-		}
-	}
-
-	*idx = -1;
-	return 0;
-}
-
-/** \ingroup desc
- * Get a USB configuration descriptor with a specific bConfigurationValue.
- * This is a non-blocking function which does not involve any requests being
- * sent to the device.
- *
- * \param dev a device
- * \param bConfigurationValue the bConfigurationValue of the configuration you
- * wish to retrieve
- * \param config output location for the USB configuration descriptor. Only
- * valid if 0 was returned. Must be freed with libusb_free_config_descriptor()
- * after use.
- * \returns 0 on success
- * \returns LIBUSB_ERROR_NOT_FOUND if the configuration does not exist
- * \returns another LIBUSB_ERROR code on error
- * \see libusb_get_active_config_descriptor()
- * \see libusb_get_config_descriptor()
- */
-int API_EXPORTED libusb_get_config_descriptor_by_value(libusb_device *dev,
-	uint8_t bConfigurationValue, struct libusb_config_descriptor **config)
-{
-	int idx;
-	int r = usbi_get_config_index_by_value(dev, bConfigurationValue, &idx);
-	if (r < 0)
-		return r;
-	else if (idx == -1)
-		return LIBUSB_ERROR_NOT_FOUND;
-	else
-		return libusb_get_config_descriptor(dev, (uint8_t) idx, config);
-}
-
-/** \ingroup desc
- * Free a configuration descriptor obtained from
- * libusb_get_active_config_descriptor() or libusb_get_config_descriptor().
- * It is safe to call this function with a NULL config parameter, in which
- * case the function simply returns.
- *
- * \param config the configuration descriptor to free
- */
-void API_EXPORTED libusb_free_config_descriptor(
-	struct libusb_config_descriptor *config)
-{
-	if (!config)
-		return;
-
-	clear_configuration(config);
-	free(config);
-}
-
-/** \ingroup desc
- * Retrieve a string descriptor in C style ASCII.
- *
- * Wrapper around libusb_get_string_descriptor(). Uses the first language
- * supported by the device.
- *
- * \param dev a device handle
- * \param desc_index the index of the descriptor to retrieve
- * \param data output buffer for ASCII string descriptor
- * \param length size of data buffer
- * \returns number of bytes returned in data, or LIBUSB_ERROR code on failure
- */
-int API_EXPORTED libusb_get_string_descriptor_ascii(libusb_device_handle *dev,
-	uint8_t desc_index, unsigned char *data, int length)
-{
-	unsigned char tbuf[255]; /* Some devices choke on size > 255 */
-	int r, si, di;
-	uint16_t langid;
-
-	/* Asking for the zero'th index is special - it returns a string
-	 * descriptor that contains all the language IDs supported by the
-	 * device. Typically there aren't many - often only one. Language
-	 * IDs are 16 bit numbers, and they start at the third byte in the
-	 * descriptor. There's also no point in trying to read descriptor 0
-	 * with this function. See USB 2.0 specification section 9.6.7 for
-	 * more information.
-	 */
-
-	if (desc_index == 0)
-		return LIBUSB_ERROR_INVALID_PARAM;
-
-	r = libusb_get_string_descriptor(dev, 0, 0, tbuf, sizeof(tbuf));
-	if (r < 0)
-		return r;
-
-	if (r < 4)
-		return LIBUSB_ERROR_IO;
-
-	langid = tbuf[2] | (tbuf[3] << 8);
-
-	r = libusb_get_string_descriptor(dev, desc_index, langid, tbuf,
-		sizeof(tbuf));
-	if (r < 0)
-		return r;
-
-	if (tbuf[1] != LIBUSB_DT_STRING)
-		return LIBUSB_ERROR_IO;
-
-	if (tbuf[0] > r)
-		return LIBUSB_ERROR_IO;
-
-	for (di = 0, si = 2; si < tbuf[0]; si += 2) {
-		if (di >= (length - 1))
-			break;
-
-		if (tbuf[si + 1]) /* high byte */
-			data[di++] = '?';
-		else
-			data[di++] = tbuf[si];
-	}
-
-	data[di] = 0;
-	return di;
-}
-
diff --git a/third_party/libusb/libusb/io.c b/third_party/libusb/libusb/io.c
deleted file mode 100644
index 51b641d..0000000
--- a/third_party/libusb/libusb/io.c
+++ /dev/null
@@ -1,2445 +0,0 @@
-/*
- * I/O functions for libusb
- * Copyright (C) 2007-2009 Daniel Drake <dsd@gentoo.org>
- * Copyright (c) 2001 Johannes Erdfelt <johannes@erdfelt.com>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#include <config.h>
-#include <errno.h>
-#include <signal.h>
-#include <stdint.h>
-#include <stdlib.h>
-#include <string.h>
-#include <time.h>
-
-#ifdef HAVE_SYS_TIME_H
-#include <sys/time.h>
-#endif
-
-#ifdef USBI_TIMERFD_AVAILABLE
-#include <sys/timerfd.h>
-#endif
-
-#include "libusbi.h"
-
-/**
- * \page io Synchronous and asynchronous device I/O
- *
- * \section intro Introduction
- *
- * If you're using libusb in your application, you're probably wanting to
- * perform I/O with devices - you want to perform USB data transfers.
- *
- * libusb offers two separate interfaces for device I/O. This page aims to
- * introduce the two in order to help you decide which one is more suitable
- * for your application. You can also choose to use both interfaces in your
- * application by considering each transfer on a case-by-case basis.
- *
- * Once you have read through the following discussion, you should consult the
- * detailed API documentation pages for the details:
- * - \ref syncio
- * - \ref asyncio
- *
- * \section theory Transfers at a logical level
- *
- * At a logical level, USB transfers typically happen in two parts. For
- * example, when reading data from a endpoint:
- * -# A request for data is sent to the device
- * -# Some time later, the incoming data is received by the host
- *
- * or when writing data to an endpoint:
- *
- * -# The data is sent to the device
- * -# Some time later, the host receives acknowledgement from the device that
- *    the data has been transferred.
- *
- * There may be an indefinite delay between the two steps. Consider a
- * fictional USB input device with a button that the user can press. In order
- * to determine when the button is pressed, you would likely submit a request
- * to read data on a bulk or interrupt endpoint and wait for data to arrive.
- * Data will arrive when the button is pressed by the user, which is
- * potentially hours later.
- *
- * libusb offers both a synchronous and an asynchronous interface to performing
- * USB transfers. The main difference is that the synchronous interface
- * combines both steps indicated above into a single function call, whereas
- * the asynchronous interface separates them.
- *
- * \section sync The synchronous interface
- *
- * The synchronous I/O interface allows you to perform a USB transfer with
- * a single function call. When the function call returns, the transfer has
- * completed and you can parse the results.
- *
- * If you have used the libusb-0.1 before, this I/O style will seem familar to
- * you. libusb-0.1 only offered a synchronous interface.
- *
- * In our input device example, to read button presses you might write code
- * in the following style:
-\code
-unsigned char data[4];
-int actual_length;
-int r = libusb_bulk_transfer(handle, LIBUSB_ENDPOINT_IN, data, sizeof(data), &actual_length, 0);
-if (r == 0 && actual_length == sizeof(data)) {
-	// results of the transaction can now be found in the data buffer
-	// parse them here and report button press
-} else {
-	error();
-}
-\endcode
- *
- * The main advantage of this model is simplicity: you did everything with
- * a single simple function call.
- *
- * However, this interface has its limitations. Your application will sleep
- * inside libusb_bulk_transfer() until the transaction has completed. If it
- * takes the user 3 hours to press the button, your application will be
- * sleeping for that long. Execution will be tied up inside the library -
- * the entire thread will be useless for that duration.
- *
- * Another issue is that by tieing up the thread with that single transaction
- * there is no possibility of performing I/O with multiple endpoints and/or
- * multiple devices simultaneously, unless you resort to creating one thread
- * per transaction.
- *
- * Additionally, there is no opportunity to cancel the transfer after the
- * request has been submitted.
- *
- * For details on how to use the synchronous API, see the
- * \ref syncio "synchronous I/O API documentation" pages.
- *
- * \section async The asynchronous interface
- *
- * Asynchronous I/O is the most significant new feature in libusb-1.0.
- * Although it is a more complex interface, it solves all the issues detailed
- * above.
- *
- * Instead of providing which functions that block until the I/O has complete,
- * libusb's asynchronous interface presents non-blocking functions which
- * begin a transfer and then return immediately. Your application passes a
- * callback function pointer to this non-blocking function, which libusb will
- * call with the results of the transaction when it has completed.
- *
- * Transfers which have been submitted through the non-blocking functions
- * can be cancelled with a separate function call.
- *
- * The non-blocking nature of this interface allows you to be simultaneously
- * performing I/O to multiple endpoints on multiple devices, without having
- * to use threads.
- *
- * This added flexibility does come with some complications though:
- * - In the interest of being a lightweight library, libusb does not create
- * threads and can only operate when your application is calling into it. Your
- * application must call into libusb from it's main loop when events are ready
- * to be handled, or you must use some other scheme to allow libusb to
- * undertake whatever work needs to be done.
- * - libusb also needs to be called into at certain fixed points in time in
- * order to accurately handle transfer timeouts.
- * - Memory handling becomes more complex. You cannot use stack memory unless
- * the function with that stack is guaranteed not to return until the transfer
- * callback has finished executing.
- * - You generally lose some linearity from your code flow because submitting
- * the transfer request is done in a separate function from where the transfer
- * results are handled. This becomes particularly obvious when you want to
- * submit a second transfer based on the results of an earlier transfer.
- *
- * Internally, libusb's synchronous interface is expressed in terms of function
- * calls to the asynchronous interface.
- *
- * For details on how to use the asynchronous API, see the
- * \ref asyncio "asynchronous I/O API" documentation pages.
- */
-
-
-/**
- * \page packetoverflow Packets and overflows
- *
- * \section packets Packet abstraction
- *
- * The USB specifications describe how data is transmitted in packets, with
- * constraints on packet size defined by endpoint descriptors. The host must
- * not send data payloads larger than the endpoint's maximum packet size.
- *
- * libusb and the underlying OS abstract out the packet concept, allowing you
- * to request transfers of any size. Internally, the request will be divided
- * up into correctly-sized packets. You do not have to be concerned with
- * packet sizes, but there is one exception when considering overflows.
- *
- * \section overflow Bulk/interrupt transfer overflows
- *
- * When requesting data on a bulk endpoint, libusb requires you to supply a
- * buffer and the maximum number of bytes of data that libusb can put in that
- * buffer. However, the size of the buffer is not communicated to the device -
- * the device is just asked to send any amount of data.
- *
- * There is no problem if the device sends an amount of data that is less than
- * or equal to the buffer size. libusb reports this condition to you through
- * the \ref libusb_transfer::actual_length "libusb_transfer.actual_length"
- * field.
- *
- * Problems may occur if the device attempts to send more data than can fit in
- * the buffer. libusb reports LIBUSB_TRANSFER_OVERFLOW for this condition but
- * other behaviour is largely undefined: actual_length may or may not be
- * accurate, the chunk of data that can fit in the buffer (before overflow)
- * may or may not have been transferred.
- *
- * Overflows are nasty, but can be avoided. Even though you were told to
- * ignore packets above, think about the lower level details: each transfer is
- * split into packets (typically small, with a maximum size of 512 bytes).
- * Overflows can only happen if the final packet in an incoming data transfer
- * is smaller than the actual packet that the device wants to transfer.
- * Therefore, you will never see an overflow if your transfer buffer size is a
- * multiple of the endpoint's packet size: the final packet will either
- * fill up completely or will be only partially filled.
- */
-
-/**
- * @defgroup asyncio Asynchronous device I/O
- *
- * This page details libusb's asynchronous (non-blocking) API for USB device
- * I/O. This interface is very powerful but is also quite complex - you will
- * need to read this page carefully to understand the necessary considerations
- * and issues surrounding use of this interface. Simplistic applications
- * may wish to consider the \ref syncio "synchronous I/O API" instead.
- *
- * The asynchronous interface is built around the idea of separating transfer
- * submission and handling of transfer completion (the synchronous model
- * combines both of these into one). There may be a long delay between
- * submission and completion, however the asynchronous submission function
- * is non-blocking so will return control to your application during that
- * potentially long delay.
- *
- * \section asyncabstraction Transfer abstraction
- *
- * For the asynchronous I/O, libusb implements the concept of a generic
- * transfer entity for all types of I/O (control, bulk, interrupt,
- * isochronous). The generic transfer object must be treated slightly
- * differently depending on which type of I/O you are performing with it.
- *
- * This is represented by the public libusb_transfer structure type.
- *
- * \section asynctrf Asynchronous transfers
- *
- * We can view asynchronous I/O as a 5 step process:
- * -# <b>Allocation</b>: allocate a libusb_transfer
- * -# <b>Filling</b>: populate the libusb_transfer instance with information
- *    about the transfer you wish to perform
- * -# <b>Submission</b>: ask libusb to submit the transfer
- * -# <b>Completion handling</b>: examine transfer results in the
- *    libusb_transfer structure
- * -# <b>Deallocation</b>: clean up resources
- *
- *
- * \subsection asyncalloc Allocation
- *
- * This step involves allocating memory for a USB transfer. This is the
- * generic transfer object mentioned above. At this stage, the transfer
- * is "blank" with no details about what type of I/O it will be used for.
- *
- * Allocation is done with the libusb_alloc_transfer() function. You must use
- * this function rather than allocating your own transfers.
- *
- * \subsection asyncfill Filling
- *
- * This step is where you take a previously allocated transfer and fill it
- * with information to determine the message type and direction, data buffer,
- * callback function, etc.
- *
- * You can either fill the required fields yourself or you can use the
- * helper functions: libusb_fill_control_transfer(), libusb_fill_bulk_transfer()
- * and libusb_fill_interrupt_transfer().
- *
- * \subsection asyncsubmit Submission
- *
- * When you have allocated a transfer and filled it, you can submit it using
- * libusb_submit_transfer(). This function returns immediately but can be
- * regarded as firing off the I/O request in the background.
- *
- * \subsection asynccomplete Completion handling
- *
- * After a transfer has been submitted, one of four things can happen to it:
- *
- * - The transfer completes (i.e. some data was transferred)
- * - The transfer has a timeout and the timeout expires before all data is
- * transferred
- * - The transfer fails due to an error
- * - The transfer is cancelled
- *
- * Each of these will cause the user-specified transfer callback function to
- * be invoked. It is up to the callback function to determine which of the
- * above actually happened and to act accordingly.
- *
- * The user-specified callback is passed a pointer to the libusb_transfer
- * structure which was used to setup and submit the transfer. At completion
- * time, libusb has populated this structure with results of the transfer:
- * success or failure reason, number of bytes of data transferred, etc. See
- * the libusb_transfer structure documentation for more information.
- *
- * \subsection Deallocation
- *
- * When a transfer has completed (i.e. the callback function has been invoked),
- * you are advised to free the transfer (unless you wish to resubmit it, see
- * below). Transfers are deallocated with libusb_free_transfer().
- *
- * It is undefined behaviour to free a transfer which has not completed.
- *
- * \section asyncresubmit Resubmission
- *
- * You may be wondering why allocation, filling, and submission are all
- * separated above where they could reasonably be combined into a single
- * operation.
- *
- * The reason for separation is to allow you to resubmit transfers without
- * having to allocate new ones every time. This is especially useful for
- * common situations dealing with interrupt endpoints - you allocate one
- * transfer, fill and submit it, and when it returns with results you just
- * resubmit it for the next interrupt.
- *
- * \section asynccancel Cancellation
- *
- * Another advantage of using the asynchronous interface is that you have
- * the ability to cancel transfers which have not yet completed. This is
- * done by calling the libusb_cancel_transfer() function.
- *
- * libusb_cancel_transfer() is asynchronous/non-blocking in itself. When the
- * cancellation actually completes, the transfer's callback function will
- * be invoked, and the callback function should check the transfer status to
- * determine that it was cancelled.
- *
- * Freeing the transfer after it has been cancelled but before cancellation
- * has completed will result in undefined behaviour.
- *
- * When a transfer is cancelled, some of the data may have been transferred.
- * libusb will communicate this to you in the transfer callback. Do not assume
- * that no data was transferred.
- *
- * \section bulk_overflows Overflows on device-to-host bulk/interrupt endpoints
- *
- * If your device does not have predictable transfer sizes (or it misbehaves),
- * your application may submit a request for data on an IN endpoint which is
- * smaller than the data that the device wishes to send. In some circumstances
- * this will cause an overflow, which is a nasty condition to deal with. See
- * the \ref packetoverflow page for discussion.
- *
- * \section asyncctrl Considerations for control transfers
- *
- * The <tt>libusb_transfer</tt> structure is generic and hence does not
- * include specific fields for the control-specific setup packet structure.
- *
- * In order to perform a control transfer, you must place the 8-byte setup
- * packet at the start of the data buffer. To simplify this, you could
- * cast the buffer pointer to type struct libusb_control_setup, or you can
- * use the helper function libusb_fill_control_setup().
- *
- * The wLength field placed in the setup packet must be the length you would
- * expect to be sent in the setup packet: the length of the payload that
- * follows (or the expected maximum number of bytes to receive). However,
- * the length field of the libusb_transfer object must be the length of
- * the data buffer - i.e. it should be wLength <em>plus</em> the size of
- * the setup packet (LIBUSB_CONTROL_SETUP_SIZE).
- *
- * If you use the helper functions, this is simplified for you:
- * -# Allocate a buffer of size LIBUSB_CONTROL_SETUP_SIZE plus the size of the
- * data you are sending/requesting.
- * -# Call libusb_fill_control_setup() on the data buffer, using the transfer
- * request size as the wLength value (i.e. do not include the extra space you
- * allocated for the control setup).
- * -# If this is a host-to-device transfer, place the data to be transferred
- * in the data buffer, starting at offset LIBUSB_CONTROL_SETUP_SIZE.
- * -# Call libusb_fill_control_transfer() to associate the data buffer with
- * the transfer (and to set the remaining details such as callback and timeout).
- *   - Note that there is no parameter to set the length field of the transfer.
- *     The length is automatically inferred from the wLength field of the setup
- *     packet.
- * -# Submit the transfer.
- *
- * The multi-byte control setup fields (wValue, wIndex and wLength) must
- * be given in little-endian byte order (the endianness of the USB bus).
- * Endianness conversion is transparently handled by
- * libusb_fill_control_setup() which is documented to accept host-endian
- * values.
- *
- * Further considerations are needed when handling transfer completion in
- * your callback function:
- * - As you might expect, the setup packet will still be sitting at the start
- * of the data buffer.
- * - If this was a device-to-host transfer, the received data will be sitting
- * at offset LIBUSB_CONTROL_SETUP_SIZE into the buffer.
- * - The actual_length field of the transfer structure is relative to the
- * wLength of the setup packet, rather than the size of the data buffer. So,
- * if your wLength was 4, your transfer's <tt>length</tt> was 12, then you
- * should expect an <tt>actual_length</tt> of 4 to indicate that the data was
- * transferred in entirity.
- *
- * To simplify parsing of setup packets and obtaining the data from the
- * correct offset, you may wish to use the libusb_control_transfer_get_data()
- * and libusb_control_transfer_get_setup() functions within your transfer
- * callback.
- *
- * Even though control endpoints do not halt, a completed control transfer
- * may have a LIBUSB_TRANSFER_STALL status code. This indicates the control
- * request was not supported.
- *
- * \section asyncintr Considerations for interrupt transfers
- *
- * All interrupt transfers are performed using the polling interval presented
- * by the bInterval value of the endpoint descriptor.
- *
- * \section asynciso Considerations for isochronous transfers
- *
- * Isochronous transfers are more complicated than transfers to
- * non-isochronous endpoints.
- *
- * To perform I/O to an isochronous endpoint, allocate the transfer by calling
- * libusb_alloc_transfer() with an appropriate number of isochronous packets.
- *
- * During filling, set \ref libusb_transfer::type "type" to
- * \ref libusb_transfer_type::LIBUSB_TRANSFER_TYPE_ISOCHRONOUS
- * "LIBUSB_TRANSFER_TYPE_ISOCHRONOUS", and set
- * \ref libusb_transfer::num_iso_packets "num_iso_packets" to a value less than
- * or equal to the number of packets you requested during allocation.
- * libusb_alloc_transfer() does not set either of these fields for you, given
- * that you might not even use the transfer on an isochronous endpoint.
- *
- * Next, populate the length field for the first num_iso_packets entries in
- * the \ref libusb_transfer::iso_packet_desc "iso_packet_desc" array. Section
- * 5.6.3 of the USB2 specifications describe how the maximum isochronous
- * packet length is determined by the wMaxPacketSize field in the endpoint
- * descriptor.
- * Two functions can help you here:
- *
- * - libusb_get_max_iso_packet_size() is an easy way to determine the max
- *   packet size for an isochronous endpoint. Note that the maximum packet
- *   size is actually the maximum number of bytes that can be transmitted in
- *   a single microframe, therefore this function multiplies the maximum number
- *   of bytes per transaction by the number of transaction opportunities per
- *   microframe.
- * - libusb_set_iso_packet_lengths() assigns the same length to all packets
- *   within a transfer, which is usually what you want.
- *
- * For outgoing transfers, you'll obviously fill the buffer and populate the
- * packet descriptors in hope that all the data gets transferred. For incoming
- * transfers, you must ensure the buffer has sufficient capacity for
- * the situation where all packets transfer the full amount of requested data.
- *
- * Completion handling requires some extra consideration. The
- * \ref libusb_transfer::actual_length "actual_length" field of the transfer
- * is meaningless and should not be examined; instead you must refer to the
- * \ref libusb_iso_packet_descriptor::actual_length "actual_length" field of
- * each individual packet.
- *
- * The \ref libusb_transfer::status "status" field of the transfer is also a
- * little misleading:
- *  - If the packets were submitted and the isochronous data microframes
- *    completed normally, status will have value
- *    \ref libusb_transfer_status::LIBUSB_TRANSFER_COMPLETED
- *    "LIBUSB_TRANSFER_COMPLETED". Note that bus errors and software-incurred
- *    delays are not counted as transfer errors; the transfer.status field may
- *    indicate COMPLETED even if some or all of the packets failed. Refer to
- *    the \ref libusb_iso_packet_descriptor::status "status" field of each
- *    individual packet to determine packet failures.
- *  - The status field will have value
- *    \ref libusb_transfer_status::LIBUSB_TRANSFER_ERROR
- *    "LIBUSB_TRANSFER_ERROR" only when serious errors were encountered.
- *  - Other transfer status codes occur with normal behaviour.
- *
- * The data for each packet will be found at an offset into the buffer that
- * can be calculated as if each prior packet completed in full. The
- * libusb_get_iso_packet_buffer() and libusb_get_iso_packet_buffer_simple()
- * functions may help you here.
- *
- * \section asyncmem Memory caveats
- *
- * In most circumstances, it is not safe to use stack memory for transfer
- * buffers. This is because the function that fired off the asynchronous
- * transfer may return before libusb has finished using the buffer, and when
- * the function returns it's stack gets destroyed. This is true for both
- * host-to-device and device-to-host transfers.
- *
- * The only case in which it is safe to use stack memory is where you can
- * guarantee that the function owning the stack space for the buffer does not
- * return until after the transfer's callback function has completed. In every
- * other case, you need to use heap memory instead.
- *
- * \section asyncflags Fine control
- *
- * Through using this asynchronous interface, you may find yourself repeating
- * a few simple operations many times. You can apply a bitwise OR of certain
- * flags to a transfer to simplify certain things:
- * - \ref libusb_transfer_flags::LIBUSB_TRANSFER_SHORT_NOT_OK
- *   "LIBUSB_TRANSFER_SHORT_NOT_OK" results in transfers which transferred
- *   less than the requested amount of data being marked with status
- *   \ref libusb_transfer_status::LIBUSB_TRANSFER_ERROR "LIBUSB_TRANSFER_ERROR"
- *   (they would normally be regarded as COMPLETED)
- * - \ref libusb_transfer_flags::LIBUSB_TRANSFER_FREE_BUFFER
- *   "LIBUSB_TRANSFER_FREE_BUFFER" allows you to ask libusb to free the transfer
- *   buffer when freeing the transfer.
- * - \ref libusb_transfer_flags::LIBUSB_TRANSFER_FREE_TRANSFER
- *   "LIBUSB_TRANSFER_FREE_TRANSFER" causes libusb to automatically free the
- *   transfer after the transfer callback returns.
- *
- * \section asyncevent Event handling
- *
- * In accordance of the aim of being a lightweight library, libusb does not
- * create threads internally. This means that libusb code does not execute
- * at any time other than when your application is calling a libusb function.
- * However, an asynchronous model requires that libusb perform work at various
- * points in time - namely processing the results of previously-submitted
- * transfers and invoking the user-supplied callback function.
- *
- * This gives rise to the libusb_handle_events() function which your
- * application must call into when libusb has work do to. This gives libusb
- * the opportunity to reap pending transfers, invoke callbacks, etc.
- *
- * The first issue to discuss here is how your application can figure out
- * when libusb has work to do. In fact, there are two naive options which
- * do not actually require your application to know this:
- * -# Periodically call libusb_handle_events() in non-blocking mode at fixed
- *    short intervals from your main loop
- * -# Repeatedly call libusb_handle_events() in blocking mode from a dedicated
- *    thread.
- *
- * The first option is plainly not very nice, and will cause unnecessary
- * CPU wakeups leading to increased power usage and decreased battery life.
- * The second option is not very nice either, but may be the nicest option
- * available to you if the "proper" approach can not be applied to your
- * application (read on...).
- *
- * The recommended option is to integrate libusb with your application main
- * event loop. libusb exposes a set of file descriptors which allow you to do
- * this. Your main loop is probably already calling poll() or select() or a
- * variant on a set of file descriptors for other event sources (e.g. keyboard
- * button presses, mouse movements, network sockets, etc). You then add
- * libusb's file descriptors to your poll()/select() calls, and when activity
- * is detected on such descriptors you know it is time to call
- * libusb_handle_events().
- *
- * There is one final event handling complication. libusb supports
- * asynchronous transfers which time out after a specified time period, and
- * this requires that libusb is called into at or after the timeout so that
- * the timeout can be handled. So, in addition to considering libusb's file
- * descriptors in your main event loop, you must also consider that libusb
- * sometimes needs to be called into at fixed points in time even when there
- * is no file descriptor activity.
- *
- * For the details on retrieving the set of file descriptors and determining
- * the next timeout, see the \ref poll "polling and timing" API documentation.
- */
-
-/**
- * @defgroup poll Polling and timing
- *
- * This page documents libusb's functions for polling events and timing.
- * These functions are only necessary for users of the
- * \ref asyncio "asynchronous API". If you are only using the simpler
- * \ref syncio "synchronous API" then you do not need to ever call these
- * functions.
- *
- * The justification for the functionality described here has already been
- * discussed in the \ref asyncevent "event handling" section of the
- * asynchronous API documentation. In summary, libusb does not create internal
- * threads for event processing and hence relies on your application calling
- * into libusb at certain points in time so that pending events can be handled.
- * In order to know precisely when libusb needs to be called into, libusb
- * offers you a set of pollable file descriptors and information about when
- * the next timeout expires.
- *
- * If you are using the asynchronous I/O API, you must take one of the two
- * following options, otherwise your I/O will not complete.
- *
- * \section pollsimple The simple option
- *
- * If your application revolves solely around libusb and does not need to
- * handle other event sources, you can have a program structure as follows:
-\code
-// initialize libusb
-// find and open device
-// maybe fire off some initial async I/O
-
-while (user_has_not_requested_exit)
-	libusb_handle_events(ctx);
-
-// clean up and exit
-\endcode
- *
- * With such a simple main loop, you do not have to worry about managing
- * sets of file descriptors or handling timeouts. libusb_handle_events() will
- * handle those details internally.
- *
- * \section pollmain The more advanced option
- *
- * \note This functionality is currently only available on Unix-like platforms.
- * On Windows, libusb_get_pollfds() simply returns NULL. Exposing event sources
- * on Windows will require some further thought and design.
- *
- * In more advanced applications, you will already have a main loop which
- * is monitoring other event sources: network sockets, X11 events, mouse
- * movements, etc. Through exposing a set of file descriptors, libusb is
- * designed to cleanly integrate into such main loops.
- *
- * In addition to polling file descriptors for the other event sources, you
- * take a set of file descriptors from libusb and monitor those too. When you
- * detect activity on libusb's file descriptors, you call
- * libusb_handle_events_timeout() in non-blocking mode.
- *
- * What's more, libusb may also need to handle events at specific moments in
- * time. No file descriptor activity is generated at these times, so your
- * own application needs to be continually aware of when the next one of these
- * moments occurs (through calling libusb_get_next_timeout()), and then it
- * needs to call libusb_handle_events_timeout() in non-blocking mode when
- * these moments occur. This means that you need to adjust your
- * poll()/select() timeout accordingly.
- *
- * libusb provides you with a set of file descriptors to poll and expects you
- * to poll all of them, treating them as a single entity. The meaning of each
- * file descriptor in the set is an internal implementation detail,
- * platform-dependent and may vary from release to release. Don't try and
- * interpret the meaning of the file descriptors, just do as libusb indicates,
- * polling all of them at once.
- *
- * In pseudo-code, you want something that looks like:
-\code
-// initialise libusb
-
-libusb_get_pollfds(ctx)
-while (user has not requested application exit) {
-	libusb_get_next_timeout(ctx);
-	poll(on libusb file descriptors plus any other event sources of interest,
-		using a timeout no larger than the value libusb just suggested)
-	if (poll() indicated activity on libusb file descriptors)
-		libusb_handle_events_timeout(ctx, &zero_tv);
-	if (time has elapsed to or beyond the libusb timeout)
-		libusb_handle_events_timeout(ctx, &zero_tv);
-	// handle events from other sources here
-}
-
-// clean up and exit
-\endcode
- *
- * \subsection polltime Notes on time-based events
- *
- * The above complication with having to track time and call into libusb at
- * specific moments is a bit of a headache. For maximum compatibility, you do
- * need to write your main loop as above, but you may decide that you can
- * restrict the supported platforms of your application and get away with
- * a more simplistic scheme.
- *
- * These time-based event complications are \b not required on the following
- * platforms:
- *  - Darwin
- *  - Linux, provided that the following version requirements are satisfied:
- *   - Linux v2.6.27 or newer, compiled with timerfd support
- *   - glibc v2.9 or newer
- *   - libusb v1.0.5 or newer
- *
- * Under these configurations, libusb_get_next_timeout() will \em always return
- * 0, so your main loop can be simplified to:
-\code
-// initialise libusb
-
-libusb_get_pollfds(ctx)
-while (user has not requested application exit) {
-	poll(on libusb file descriptors plus any other event sources of interest,
-		using any timeout that you like)
-	if (poll() indicated activity on libusb file descriptors)
-		libusb_handle_events_timeout(ctx, &zero_tv);
-	// handle events from other sources here
-}
-
-// clean up and exit
-\endcode
- *
- * Do remember that if you simplify your main loop to the above, you will
- * lose compatibility with some platforms (including legacy Linux platforms,
- * and <em>any future platforms supported by libusb which may have time-based
- * event requirements</em>). The resultant problems will likely appear as
- * strange bugs in your application.
- *
- * You can use the libusb_pollfds_handle_timeouts() function to do a runtime
- * check to see if it is safe to ignore the time-based event complications.
- * If your application has taken the shortcut of ignoring libusb's next timeout
- * in your main loop, then you are advised to check the return value of
- * libusb_pollfds_handle_timeouts() during application startup, and to abort
- * if the platform does suffer from these timing complications.
- *
- * \subsection fdsetchange Changes in the file descriptor set
- *
- * The set of file descriptors that libusb uses as event sources may change
- * during the life of your application. Rather than having to repeatedly
- * call libusb_get_pollfds(), you can set up notification functions for when
- * the file descriptor set changes using libusb_set_pollfd_notifiers().
- *
- * \subsection mtissues Multi-threaded considerations
- *
- * Unfortunately, the situation is complicated further when multiple threads
- * come into play. If two threads are monitoring the same file descriptors,
- * the fact that only one thread will be woken up when an event occurs causes
- * some headaches.
- *
- * The events lock, event waiters lock, and libusb_handle_events_locked()
- * entities are added to solve these problems. You do not need to be concerned
- * with these entities otherwise.
- *
- * See the extra documentation: \ref mtasync
- */
-
-/** \page mtasync Multi-threaded applications and asynchronous I/O
- *
- * libusb is a thread-safe library, but extra considerations must be applied
- * to applications which interact with libusb from multiple threads.
- *
- * The underlying issue that must be addressed is that all libusb I/O
- * revolves around monitoring file descriptors through the poll()/select()
- * system calls. This is directly exposed at the
- * \ref asyncio "asynchronous interface" but it is important to note that the
- * \ref syncio "synchronous interface" is implemented on top of the
- * asynchonrous interface, therefore the same considerations apply.
- *
- * The issue is that if two or more threads are concurrently calling poll()
- * or select() on libusb's file descriptors then only one of those threads
- * will be woken up when an event arrives. The others will be completely
- * oblivious that anything has happened.
- *
- * Consider the following pseudo-code, which submits an asynchronous transfer
- * then waits for its completion. This style is one way you could implement a
- * synchronous interface on top of the asynchronous interface (and libusb
- * does something similar, albeit more advanced due to the complications
- * explained on this page).
- *
-\code
-void cb(struct libusb_transfer *transfer)
-{
-	int *completed = transfer->user_data;
-	*completed = 1;
-}
-
-void myfunc() {
-	struct libusb_transfer *transfer;
-	unsigned char buffer[LIBUSB_CONTROL_SETUP_SIZE];
-	int completed = 0;
-
-	transfer = libusb_alloc_transfer(0);
-	libusb_fill_control_setup(buffer,
-		LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_ENDPOINT_OUT, 0x04, 0x01, 0, 0);
-	libusb_fill_control_transfer(transfer, dev, buffer, cb, &completed, 1000);
-	libusb_submit_transfer(transfer);
-
-	while (!completed) {
-		poll(libusb file descriptors, 120*1000);
-		if (poll indicates activity)
-			libusb_handle_events_timeout(ctx, &zero_tv);
-	}
-	printf("completed!");
-	// other code here
-}
-\endcode
- *
- * Here we are <em>serializing</em> completion of an asynchronous event
- * against a condition - the condition being completion of a specific transfer.
- * The poll() loop has a long timeout to minimize CPU usage during situations
- * when nothing is happening (it could reasonably be unlimited).
- *
- * If this is the only thread that is polling libusb's file descriptors, there
- * is no problem: there is no danger that another thread will swallow up the
- * event that we are interested in. On the other hand, if there is another
- * thread polling the same descriptors, there is a chance that it will receive
- * the event that we were interested in. In this situation, <tt>myfunc()</tt>
- * will only realise that the transfer has completed on the next iteration of
- * the loop, <em>up to 120 seconds later.</em> Clearly a two-minute delay is
- * undesirable, and don't even think about using short timeouts to circumvent
- * this issue!
- *
- * The solution here is to ensure that no two threads are ever polling the
- * file descriptors at the same time. A naive implementation of this would
- * impact the capabilities of the library, so libusb offers the scheme
- * documented below to ensure no loss of functionality.
- *
- * Before we go any further, it is worth mentioning that all libusb-wrapped
- * event handling procedures fully adhere to the scheme documented below.
- * This includes libusb_handle_events() and its variants, and all the
- * synchronous I/O functions - libusb hides this headache from you.
- *
- * \section Using libusb_handle_events() from multiple threads
- *
- * Even when only using libusb_handle_events() and synchronous I/O functions,
- * you can still have a race condition. You might be tempted to solve the
- * above with libusb_handle_events() like so:
- *
-\code
-	libusb_submit_transfer(transfer);
-
-	while (!completed) {
-		libusb_handle_events(ctx);
-	}
-	printf("completed!");
-\endcode
- *
- * This however has a race between the checking of completed and
- * libusb_handle_events() acquiring the events lock, so another thread
- * could have completed the transfer, resulting in this thread hanging
- * until either a timeout or another event occurs. See also commit
- * 6696512aade99bb15d6792af90ae329af270eba6 which fixes this in the
- * synchronous API implementation of libusb.
- *
- * Fixing this race requires checking the variable completed only after
- * taking the event lock, which defeats the concept of just calling
- * libusb_handle_events() without worrying about locking. This is why
- * libusb-1.0.9 introduces the new libusb_handle_events_timeout_completed()
- * and libusb_handle_events_completed() functions, which handles doing the
- * completion check for you after they have acquired the lock:
- *
-\code
-	libusb_submit_transfer(transfer);
-
-	while (!completed) {
-		libusb_handle_events_completed(ctx, &completed);
-	}
-	printf("completed!");
-\endcode
- *
- * This nicely fixes the race in our example. Note that if all you want to
- * do is submit a single transfer and wait for its completion, then using
- * one of the synchronous I/O functions is much easier.
- *
- * \section eventlock The events lock
- *
- * The problem is when we consider the fact that libusb exposes file
- * descriptors to allow for you to integrate asynchronous USB I/O into
- * existing main loops, effectively allowing you to do some work behind
- * libusb's back. If you do take libusb's file descriptors and pass them to
- * poll()/select() yourself, you need to be aware of the associated issues.
- *
- * The first concept to be introduced is the events lock. The events lock
- * is used to serialize threads that want to handle events, such that only
- * one thread is handling events at any one time.
- *
- * You must take the events lock before polling libusb file descriptors,
- * using libusb_lock_events(). You must release the lock as soon as you have
- * aborted your poll()/select() loop, using libusb_unlock_events().
- *
- * \section threadwait Letting other threads do the work for you
- *
- * Although the events lock is a critical part of the solution, it is not
- * enough on it's own. You might wonder if the following is sufficient...
-\code
-	libusb_lock_events(ctx);
-	while (!completed) {
-		poll(libusb file descriptors, 120*1000);
-		if (poll indicates activity)
-			libusb_handle_events_timeout(ctx, &zero_tv);
-	}
-	libusb_unlock_events(ctx);
-\endcode
- * ...and the answer is that it is not. This is because the transfer in the
- * code shown above may take a long time (say 30 seconds) to complete, and
- * the lock is not released until the transfer is completed.
- *
- * Another thread with similar code that wants to do event handling may be
- * working with a transfer that completes after a few milliseconds. Despite
- * having such a quick completion time, the other thread cannot check that
- * status of its transfer until the code above has finished (30 seconds later)
- * due to contention on the lock.
- *
- * To solve this, libusb offers you a mechanism to determine when another
- * thread is handling events. It also offers a mechanism to block your thread
- * until the event handling thread has completed an event (and this mechanism
- * does not involve polling of file descriptors).
- *
- * After determining that another thread is currently handling events, you
- * obtain the <em>event waiters</em> lock using libusb_lock_event_waiters().
- * You then re-check that some other thread is still handling events, and if
- * so, you call libusb_wait_for_event().
- *
- * libusb_wait_for_event() puts your application to sleep until an event
- * occurs, or until a thread releases the events lock. When either of these
- * things happen, your thread is woken up, and should re-check the condition
- * it was waiting on. It should also re-check that another thread is handling
- * events, and if not, it should start handling events itself.
- *
- * This looks like the following, as pseudo-code:
-\code
-retry:
-if (libusb_try_lock_events(ctx) == 0) {
-	// we obtained the event lock: do our own event handling
-	while (!completed) {
-		if (!libusb_event_handling_ok(ctx)) {
-			libusb_unlock_events(ctx);
-			goto retry;
-		}
-		poll(libusb file descriptors, 120*1000);
-		if (poll indicates activity)
-			libusb_handle_events_locked(ctx, 0);
-	}
-	libusb_unlock_events(ctx);
-} else {
-	// another thread is doing event handling. wait for it to signal us that
-	// an event has completed
-	libusb_lock_event_waiters(ctx);
-
-	while (!completed) {
-		// now that we have the event waiters lock, double check that another
-		// thread is still handling events for us. (it may have ceased handling
-		// events in the time it took us to reach this point)
-		if (!libusb_event_handler_active(ctx)) {
-			// whoever was handling events is no longer doing so, try again
-			libusb_unlock_event_waiters(ctx);
-			goto retry;
-		}
-
-		libusb_wait_for_event(ctx, NULL);
-	}
-	libusb_unlock_event_waiters(ctx);
-}
-printf("completed!\n");
-\endcode
- *
- * A naive look at the above code may suggest that this can only support
- * one event waiter (hence a total of 2 competing threads, the other doing
- * event handling), because the event waiter seems to have taken the event
- * waiters lock while waiting for an event. However, the system does support
- * multiple event waiters, because libusb_wait_for_event() actually drops
- * the lock while waiting, and reaquires it before continuing.
- *
- * We have now implemented code which can dynamically handle situations where
- * nobody is handling events (so we should do it ourselves), and it can also
- * handle situations where another thread is doing event handling (so we can
- * piggyback onto them). It is also equipped to handle a combination of
- * the two, for example, another thread is doing event handling, but for
- * whatever reason it stops doing so before our condition is met, so we take
- * over the event handling.
- *
- * Four functions were introduced in the above pseudo-code. Their importance
- * should be apparent from the code shown above.
- * -# libusb_try_lock_events() is a non-blocking function which attempts
- *    to acquire the events lock but returns a failure code if it is contended.
- * -# libusb_event_handling_ok() checks that libusb is still happy for your
- *    thread to be performing event handling. Sometimes, libusb needs to
- *    interrupt the event handler, and this is how you can check if you have
- *    been interrupted. If this function returns 0, the correct behaviour is
- *    for you to give up the event handling lock, and then to repeat the cycle.
- *    The following libusb_try_lock_events() will fail, so you will become an
- *    events waiter. For more information on this, read \ref fullstory below.
- * -# libusb_handle_events_locked() is a variant of
- *    libusb_handle_events_timeout() that you can call while holding the
- *    events lock. libusb_handle_events_timeout() itself implements similar
- *    logic to the above, so be sure not to call it when you are
- *    "working behind libusb's back", as is the case here.
- * -# libusb_event_handler_active() determines if someone is currently
- *    holding the events lock
- *
- * You might be wondering why there is no function to wake up all threads
- * blocked on libusb_wait_for_event(). This is because libusb can do this
- * internally: it will wake up all such threads when someone calls
- * libusb_unlock_events() or when a transfer completes (at the point after its
- * callback has returned).
- *
- * \subsection fullstory The full story
- *
- * The above explanation should be enough to get you going, but if you're
- * really thinking through the issues then you may be left with some more
- * questions regarding libusb's internals. If you're curious, read on, and if
- * not, skip to the next section to avoid confusing yourself!
- *
- * The immediate question that may spring to mind is: what if one thread
- * modifies the set of file descriptors that need to be polled while another
- * thread is doing event handling?
- *
- * There are 2 situations in which this may happen.
- * -# libusb_open() will add another file descriptor to the poll set,
- *    therefore it is desirable to interrupt the event handler so that it
- *    restarts, picking up the new descriptor.
- * -# libusb_close() will remove a file descriptor from the poll set. There
- *    are all kinds of race conditions that could arise here, so it is
- *    important that nobody is doing event handling at this time.
- *
- * libusb handles these issues internally, so application developers do not
- * have to stop their event handlers while opening/closing devices. Here's how
- * it works, focusing on the libusb_close() situation first:
- *
- * -# During initialization, libusb opens an internal pipe, and it adds the read
- *    end of this pipe to the set of file descriptors to be polled.
- * -# During libusb_close(), libusb writes some dummy data on this control pipe.
- *    This immediately interrupts the event handler. libusb also records
- *    internally that it is trying to interrupt event handlers for this
- *    high-priority event.
- * -# At this point, some of the functions described above start behaving
- *    differently:
- *   - libusb_event_handling_ok() starts returning 1, indicating that it is NOT
- *     OK for event handling to continue.
- *   - libusb_try_lock_events() starts returning 1, indicating that another
- *     thread holds the event handling lock, even if the lock is uncontended.
- *   - libusb_event_handler_active() starts returning 1, indicating that
- *     another thread is doing event handling, even if that is not true.
- * -# The above changes in behaviour result in the event handler stopping and
- *    giving up the events lock very quickly, giving the high-priority
- *    libusb_close() operation a "free ride" to acquire the events lock. All
- *    threads that are competing to do event handling become event waiters.
- * -# With the events lock held inside libusb_close(), libusb can safely remove
- *    a file descriptor from the poll set, in the safety of knowledge that
- *    nobody is polling those descriptors or trying to access the poll set.
- * -# After obtaining the events lock, the close operation completes very
- *    quickly (usually a matter of milliseconds) and then immediately releases
- *    the events lock.
- * -# At the same time, the behaviour of libusb_event_handling_ok() and friends
- *    reverts to the original, documented behaviour.
- * -# The release of the events lock causes the threads that are waiting for
- *    events to be woken up and to start competing to become event handlers
- *    again. One of them will succeed; it will then re-obtain the list of poll
- *    descriptors, and USB I/O will then continue as normal.
- *
- * libusb_open() is similar, and is actually a more simplistic case. Upon a
- * call to libusb_open():
- *
- * -# The device is opened and a file descriptor is added to the poll set.
- * -# libusb sends some dummy data on the control pipe, and records that it
- *    is trying to modify the poll descriptor set.
- * -# The event handler is interrupted, and the same behaviour change as for
- *    libusb_close() takes effect, causing all event handling threads to become
- *    event waiters.
- * -# The libusb_open() implementation takes its free ride to the events lock.
- * -# Happy that it has successfully paused the events handler, libusb_open()
- *    releases the events lock.
- * -# The event waiter threads are all woken up and compete to become event
- *    handlers again. The one that succeeds will obtain the list of poll
- *    descriptors again, which will include the addition of the new device.
- *
- * \subsection concl Closing remarks
- *
- * The above may seem a little complicated, but hopefully I have made it clear
- * why such complications are necessary. Also, do not forget that this only
- * applies to applications that take libusb's file descriptors and integrate
- * them into their own polling loops.
- *
- * You may decide that it is OK for your multi-threaded application to ignore
- * some of the rules and locks detailed above, because you don't think that
- * two threads can ever be polling the descriptors at the same time. If that
- * is the case, then that's good news for you because you don't have to worry.
- * But be careful here; remember that the synchronous I/O functions do event
- * handling internally. If you have one thread doing event handling in a loop
- * (without implementing the rules and locking semantics documented above)
- * and another trying to send a synchronous USB transfer, you will end up with
- * two threads monitoring the same descriptors, and the above-described
- * undesirable behaviour occuring. The solution is for your polling thread to
- * play by the rules; the synchronous I/O functions do so, and this will result
- * in them getting along in perfect harmony.
- *
- * If you do have a dedicated thread doing event handling, it is perfectly
- * legal for it to take the event handling lock for long periods of time. Any
- * synchronous I/O functions you call from other threads will transparently
- * fall back to the "event waiters" mechanism detailed above. The only
- * consideration that your event handling thread must apply is the one related
- * to libusb_event_handling_ok(): you must call this before every poll(), and
- * give up the events lock if instructed.
- */
-
-int usbi_io_init(struct libusb_context *ctx)
-{
-	int r;
-
-	usbi_mutex_init(&ctx->flying_transfers_lock, NULL);
-	usbi_mutex_init(&ctx->pollfds_lock, NULL);
-	usbi_mutex_init(&ctx->pollfd_modify_lock, NULL);
-	usbi_mutex_init_recursive(&ctx->events_lock, NULL);
-	usbi_mutex_init(&ctx->event_waiters_lock, NULL);
-	usbi_cond_init(&ctx->event_waiters_cond, NULL);
-	list_init(&ctx->flying_transfers);
-	list_init(&ctx->pollfds);
-
-	/* FIXME should use an eventfd on kernels that support it */
-	r = usbi_pipe(ctx->ctrl_pipe);
-	if (r < 0) {
-		r = LIBUSB_ERROR_OTHER;
-		goto err;
-	}
-
-	r = usbi_add_pollfd(ctx, ctx->ctrl_pipe[0], POLLIN);
-	if (r < 0)
-		goto err_close_pipe;
-
-#ifdef USBI_TIMERFD_AVAILABLE
-	ctx->timerfd = timerfd_create(usbi_backend->get_timerfd_clockid(),
-		TFD_NONBLOCK);
-	if (ctx->timerfd >= 0) {
-		usbi_dbg("using timerfd for timeouts");
-		r = usbi_add_pollfd(ctx, ctx->timerfd, POLLIN);
-		if (r < 0) {
-			usbi_remove_pollfd(ctx, ctx->ctrl_pipe[0]);
-			close(ctx->timerfd);
-			goto err_close_pipe;
-		}
-	} else {
-		usbi_dbg("timerfd not available (code %d error %d)", ctx->timerfd, errno);
-		ctx->timerfd = -1;
-	}
-#endif
-
-	return 0;
-
-err_close_pipe:
-	usbi_close(ctx->ctrl_pipe[0]);
-	usbi_close(ctx->ctrl_pipe[1]);
-err:
-	usbi_mutex_destroy(&ctx->flying_transfers_lock);
-	usbi_mutex_destroy(&ctx->pollfds_lock);
-	usbi_mutex_destroy(&ctx->pollfd_modify_lock);
-	usbi_mutex_destroy(&ctx->events_lock);
-	usbi_mutex_destroy(&ctx->event_waiters_lock);
-	usbi_cond_destroy(&ctx->event_waiters_cond);
-	return r;
-}
-
-void usbi_io_exit(struct libusb_context *ctx)
-{
-	usbi_remove_pollfd(ctx, ctx->ctrl_pipe[0]);
-	usbi_close(ctx->ctrl_pipe[0]);
-	usbi_close(ctx->ctrl_pipe[1]);
-#ifdef USBI_TIMERFD_AVAILABLE
-	if (usbi_using_timerfd(ctx)) {
-		usbi_remove_pollfd(ctx, ctx->timerfd);
-		close(ctx->timerfd);
-	}
-#endif
-	usbi_mutex_destroy(&ctx->flying_transfers_lock);
-	usbi_mutex_destroy(&ctx->pollfds_lock);
-	usbi_mutex_destroy(&ctx->pollfd_modify_lock);
-	usbi_mutex_destroy(&ctx->events_lock);
-	usbi_mutex_destroy(&ctx->event_waiters_lock);
-	usbi_cond_destroy(&ctx->event_waiters_cond);
-}
-
-static int calculate_timeout(struct usbi_transfer *transfer)
-{
-	int r;
-	struct timespec current_time;
-	unsigned int timeout =
-		USBI_TRANSFER_TO_LIBUSB_TRANSFER(transfer)->timeout;
-
-	if (!timeout)
-		return 0;
-
-	r = usbi_backend->clock_gettime(USBI_CLOCK_MONOTONIC, &current_time);
-	if (r < 0) {
-		usbi_err(ITRANSFER_CTX(transfer),
-			"failed to read monotonic clock, errno=%d", errno);
-		return r;
-	}
-
-	current_time.tv_sec += timeout / 1000;
-	current_time.tv_nsec += (timeout % 1000) * 1000000;
-
-	if (current_time.tv_nsec > 1000000000) {
-		current_time.tv_nsec -= 1000000000;
-		current_time.tv_sec++;
-	}
-
-	TIMESPEC_TO_TIMEVAL(&transfer->timeout, &current_time);
-	return 0;
-}
-
-/* add a transfer to the (timeout-sorted) active transfers list.
- * returns 1 if the transfer has a timeout and it is the timeout next to
- * expire */
-static int add_to_flying_list(struct usbi_transfer *transfer)
-{
-	struct usbi_transfer *cur;
-	struct timeval *timeout = &transfer->timeout;
-	struct libusb_context *ctx = ITRANSFER_CTX(transfer);
-	int r = 0;
-	int first = 1;
-
-	usbi_mutex_lock(&ctx->flying_transfers_lock);
-
-	/* if we have no other flying transfers, start the list with this one */
-	if (list_empty(&ctx->flying_transfers)) {
-		list_add(&transfer->list, &ctx->flying_transfers);
-		if (timerisset(timeout))
-			r = 1;
-		goto out;
-	}
-
-	/* if we have infinite timeout, append to end of list */
-	if (!timerisset(timeout)) {
-		list_add_tail(&transfer->list, &ctx->flying_transfers);
-		goto out;
-	}
-
-	/* otherwise, find appropriate place in list */
-	list_for_each_entry(cur, &ctx->flying_transfers, list, struct usbi_transfer) {
-		/* find first timeout that occurs after the transfer in question */
-		struct timeval *cur_tv = &cur->timeout;
-
-		if (!timerisset(cur_tv) || (cur_tv->tv_sec > timeout->tv_sec) ||
-				(cur_tv->tv_sec == timeout->tv_sec &&
-					cur_tv->tv_usec > timeout->tv_usec)) {
-			list_add_tail(&transfer->list, &cur->list);
-			r = first;
-			goto out;
-		}
-		first = 0;
-	}
-
-	/* otherwise we need to be inserted at the end */
-	list_add_tail(&transfer->list, &ctx->flying_transfers);
-out:
-	usbi_mutex_unlock(&ctx->flying_transfers_lock);
-	return r;
-}
-
-/** \ingroup asyncio
- * Allocate a libusb transfer with a specified number of isochronous packet
- * descriptors. The returned transfer is pre-initialized for you. When the new
- * transfer is no longer needed, it should be freed with
- * libusb_free_transfer().
- *
- * Transfers intended for non-isochronous endpoints (e.g. control, bulk,
- * interrupt) should specify an iso_packets count of zero.
- *
- * For transfers intended for isochronous endpoints, specify an appropriate
- * number of packet descriptors to be allocated as part of the transfer.
- * The returned transfer is not specially initialized for isochronous I/O;
- * you are still required to set the
- * \ref libusb_transfer::num_iso_packets "num_iso_packets" and
- * \ref libusb_transfer::type "type" fields accordingly.
- *
- * It is safe to allocate a transfer with some isochronous packets and then
- * use it on a non-isochronous endpoint. If you do this, ensure that at time
- * of submission, num_iso_packets is 0 and that type is set appropriately.
- *
- * \param iso_packets number of isochronous packet descriptors to allocate
- * \returns a newly allocated transfer, or NULL on error
- */
-DEFAULT_VISIBILITY
-struct libusb_transfer * LIBUSB_CALL libusb_alloc_transfer(
-	int iso_packets)
-{
-	size_t os_alloc_size = usbi_backend->transfer_priv_size
-		+ (usbi_backend->add_iso_packet_size * iso_packets);
-	size_t alloc_size = sizeof(struct usbi_transfer)
-		+ sizeof(struct libusb_transfer)
-		+ (sizeof(struct libusb_iso_packet_descriptor) * iso_packets)
-		+ os_alloc_size;
-	struct usbi_transfer *itransfer = malloc(alloc_size);
-	if (!itransfer)
-		return NULL;
-
-	memset(itransfer, 0, alloc_size);
-	itransfer->num_iso_packets = iso_packets;
-	usbi_mutex_init(&itransfer->lock, NULL);
-	return USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-}
-
-/** \ingroup asyncio
- * Free a transfer structure. This should be called for all transfers
- * allocated with libusb_alloc_transfer().
- *
- * If the \ref libusb_transfer_flags::LIBUSB_TRANSFER_FREE_BUFFER
- * "LIBUSB_TRANSFER_FREE_BUFFER" flag is set and the transfer buffer is
- * non-NULL, this function will also free the transfer buffer using the
- * standard system memory allocator (e.g. free()).
- *
- * It is legal to call this function with a NULL transfer. In this case,
- * the function will simply return safely.
- *
- * It is not legal to free an active transfer (one which has been submitted
- * and has not yet completed).
- *
- * \param transfer the transfer to free
- */
-void API_EXPORTED libusb_free_transfer(struct libusb_transfer *transfer)
-{
-	struct usbi_transfer *itransfer;
-	if (!transfer)
-		return;
-
-	if (transfer->flags & LIBUSB_TRANSFER_FREE_BUFFER && transfer->buffer)
-		free(transfer->buffer);
-
-	itransfer = LIBUSB_TRANSFER_TO_USBI_TRANSFER(transfer);
-	usbi_mutex_destroy(&itransfer->lock);
-	free(itransfer);
-}
-
-/** \ingroup asyncio
- * Submit a transfer. This function will fire off the USB transfer and then
- * return immediately.
- *
- * \param transfer the transfer to submit
- * \returns 0 on success
- * \returns LIBUSB_ERROR_NO_DEVICE if the device has been disconnected
- * \returns LIBUSB_ERROR_BUSY if the transfer has already been submitted.
- * \returns another LIBUSB_ERROR code on other failure
- */
-int API_EXPORTED libusb_submit_transfer(struct libusb_transfer *transfer)
-{
-	struct libusb_context *ctx = TRANSFER_CTX(transfer);
-	struct usbi_transfer *itransfer =
-		LIBUSB_TRANSFER_TO_USBI_TRANSFER(transfer);
-	int r;
-	int first;
-
-	usbi_mutex_lock(&itransfer->lock);
-	itransfer->transferred = 0;
-	itransfer->flags = 0;
-	r = calculate_timeout(itransfer);
-	if (r < 0) {
-		r = LIBUSB_ERROR_OTHER;
-		goto out;
-	}
-
-	first = add_to_flying_list(itransfer);
-	r = usbi_backend->submit_transfer(itransfer);
-	if (r) {
-		usbi_mutex_lock(&ctx->flying_transfers_lock);
-		list_del(&itransfer->list);
-		usbi_mutex_unlock(&ctx->flying_transfers_lock);
-	}
-#ifdef USBI_TIMERFD_AVAILABLE
-	else if (first && usbi_using_timerfd(ctx)) {
-		/* if this transfer has the lowest timeout of all active transfers,
-		 * rearm the timerfd with this transfer's timeout */
-		const struct itimerspec it = { {0, 0},
-			{ itransfer->timeout.tv_sec, itransfer->timeout.tv_usec * 1000 } };
-		usbi_dbg("arm timerfd for timeout in %dms (first in line)", transfer->timeout);
-		r = timerfd_settime(ctx->timerfd, TFD_TIMER_ABSTIME, &it, NULL);
-		if (r < 0)
-			r = LIBUSB_ERROR_OTHER;
-	}
-#else
-	(void)first;
-#endif
-
-out:
-	usbi_mutex_unlock(&itransfer->lock);
-	return r;
-}
-
-/** \ingroup asyncio
- * Asynchronously cancel a previously submitted transfer.
- * This function returns immediately, but this does not indicate cancellation
- * is complete. Your callback function will be invoked at some later time
- * with a transfer status of
- * \ref libusb_transfer_status::LIBUSB_TRANSFER_CANCELLED
- * "LIBUSB_TRANSFER_CANCELLED."
- *
- * \param transfer the transfer to cancel
- * \returns 0 on success
- * \returns LIBUSB_ERROR_NOT_FOUND if the transfer is already complete or
- * cancelled.
- * \returns a LIBUSB_ERROR code on failure
- */
-int API_EXPORTED libusb_cancel_transfer(struct libusb_transfer *transfer)
-{
-	struct usbi_transfer *itransfer =
-		LIBUSB_TRANSFER_TO_USBI_TRANSFER(transfer);
-	int r;
-
-	usbi_dbg("");
-	usbi_mutex_lock(&itransfer->lock);
-	r = usbi_backend->cancel_transfer(itransfer);
-	if (r < 0) {
-		usbi_err(TRANSFER_CTX(transfer),
-			"cancel transfer failed error %d", r);
-
-		if (r == LIBUSB_ERROR_NO_DEVICE)
-			itransfer->flags |= USBI_TRANSFER_DEVICE_DISAPPEARED;
-	}
-
-	itransfer->flags |= USBI_TRANSFER_CANCELLING;
-
-	usbi_mutex_unlock(&itransfer->lock);
-	return r;
-}
-
-#ifdef USBI_TIMERFD_AVAILABLE
-static int disarm_timerfd(struct libusb_context *ctx)
-{
-	const struct itimerspec disarm_timer = { { 0, 0 }, { 0, 0 } };
-	int r;
-
-	usbi_dbg("");
-	r = timerfd_settime(ctx->timerfd, 0, &disarm_timer, NULL);
-	if (r < 0)
-		return LIBUSB_ERROR_OTHER;
-	else
-		return 0;
-}
-
-/* iterates through the flying transfers, and rearms the timerfd based on the
- * next upcoming timeout.
- * must be called with flying_list locked.
- * returns 0 if there was no timeout to arm, 1 if the next timeout was armed,
- * or a LIBUSB_ERROR code on failure.
- */
-static int arm_timerfd_for_next_timeout(struct libusb_context *ctx)
-{
-	struct usbi_transfer *transfer;
-
-	list_for_each_entry(transfer, &ctx->flying_transfers, list, struct usbi_transfer) {
-		struct timeval *cur_tv = &transfer->timeout;
-
-		/* if we've reached transfers of infinite timeout, then we have no
-		 * arming to do */
-		if (!timerisset(cur_tv))
-			return 0;
-
-		/* act on first transfer that is not already cancelled */
-		if (!(transfer->flags & USBI_TRANSFER_TIMED_OUT)) {
-			int r;
-			const struct itimerspec it = { {0, 0},
-				{ cur_tv->tv_sec, cur_tv->tv_usec * 1000 } };
-			usbi_dbg("next timeout originally %dms", USBI_TRANSFER_TO_LIBUSB_TRANSFER(transfer)->timeout);
-			r = timerfd_settime(ctx->timerfd, TFD_TIMER_ABSTIME, &it, NULL);
-			if (r < 0)
-				return LIBUSB_ERROR_OTHER;
-			return 1;
-		}
-	}
-
-	return 0;
-}
-#else
-static int disarm_timerfd(struct libusb_context *ctx)
-{
-	(void)ctx;
-	return 0;
-}
-static int arm_timerfd_for_next_timeout(struct libusb_context *ctx)
-{
-	(void)ctx;
-	return 0;
-}
-#endif
-
-/* Handle completion of a transfer (completion might be an error condition).
- * This will invoke the user-supplied callback function, which may end up
- * freeing the transfer. Therefore you cannot use the transfer structure
- * after calling this function, and you should free all backend-specific
- * data before calling it.
- * Do not call this function with the usbi_transfer lock held. User-specified
- * callback functions may attempt to directly resubmit the transfer, which
- * will attempt to take the lock. */
-int usbi_handle_transfer_completion(struct usbi_transfer *itransfer,
-	enum libusb_transfer_status status)
-{
-	struct libusb_transfer *transfer =
-		USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	struct libusb_context *ctx = TRANSFER_CTX(transfer);
-	uint8_t flags;
-	int r;
-
-	/* FIXME: could be more intelligent with the timerfd here. we don't need
-	 * to disarm the timerfd if there was no timer running, and we only need
-	 * to rearm the timerfd if the transfer that expired was the one with
-	 * the shortest timeout. */
-
-	usbi_mutex_lock(&ctx->flying_transfers_lock);
-	list_del(&itransfer->list);
-	r = arm_timerfd_for_next_timeout(ctx);
-	usbi_mutex_unlock(&ctx->flying_transfers_lock);
-
-	if (r < 0) {
-		return r;
-	} else if (r == 0) {
-		r = disarm_timerfd(ctx);
-		if (r < 0)
-			return r;
-	}
-
-	if (status == LIBUSB_TRANSFER_COMPLETED
-			&& transfer->flags & LIBUSB_TRANSFER_SHORT_NOT_OK) {
-		int rqlen = transfer->length;
-		if (transfer->type == LIBUSB_TRANSFER_TYPE_CONTROL)
-			rqlen -= LIBUSB_CONTROL_SETUP_SIZE;
-		if (rqlen != itransfer->transferred) {
-			usbi_dbg("interpreting short transfer as error");
-			status = LIBUSB_TRANSFER_ERROR;
-		}
-	}
-
-	flags = transfer->flags;
-	transfer->status = status;
-	transfer->actual_length = itransfer->transferred;
-	if (transfer->callback)
-		transfer->callback(transfer);
-	/* transfer might have been freed by the above call, do not use from
-	 * this point. */
-	if (flags & LIBUSB_TRANSFER_FREE_TRANSFER)
-		libusb_free_transfer(transfer);
-	usbi_mutex_lock(&ctx->event_waiters_lock);
-	usbi_cond_broadcast(&ctx->event_waiters_cond);
-	usbi_mutex_unlock(&ctx->event_waiters_lock);
-	return 0;
-}
-
-/* Similar to usbi_handle_transfer_completion() but exclusively for transfers
- * that were asynchronously cancelled. The same concerns w.r.t. freeing of
- * transfers exist here.
- * Do not call this function with the usbi_transfer lock held. User-specified
- * callback functions may attempt to directly resubmit the transfer, which
- * will attempt to take the lock. */
-int usbi_handle_transfer_cancellation(struct usbi_transfer *transfer)
-{
-	/* if the URB was cancelled due to timeout, report timeout to the user */
-	if (transfer->flags & USBI_TRANSFER_TIMED_OUT) {
-		usbi_dbg("detected timeout cancellation");
-		return usbi_handle_transfer_completion(transfer, LIBUSB_TRANSFER_TIMED_OUT);
-	}
-
-	/* otherwise its a normal async cancel */
-	return usbi_handle_transfer_completion(transfer, LIBUSB_TRANSFER_CANCELLED);
-}
-
-/** \ingroup poll
- * Attempt to acquire the event handling lock. This lock is used to ensure that
- * only one thread is monitoring libusb event sources at any one time.
- *
- * You only need to use this lock if you are developing an application
- * which calls poll() or select() on libusb's file descriptors directly.
- * If you stick to libusb's event handling loop functions (e.g.
- * libusb_handle_events()) then you do not need to be concerned with this
- * locking.
- *
- * While holding this lock, you are trusted to actually be handling events.
- * If you are no longer handling events, you must call libusb_unlock_events()
- * as soon as possible.
- *
- * \param ctx the context to operate on, or NULL for the default context
- * \returns 0 if the lock was obtained successfully
- * \returns 1 if the lock was not obtained (i.e. another thread holds the lock)
- * \see \ref mtasync
- */
-int API_EXPORTED libusb_try_lock_events(libusb_context *ctx)
-{
-	int r;
-	USBI_GET_CONTEXT(ctx);
-
-	/* is someone else waiting to modify poll fds? if so, don't let this thread
-	 * start event handling */
-	usbi_mutex_lock(&ctx->pollfd_modify_lock);
-	r = ctx->pollfd_modify;
-	usbi_mutex_unlock(&ctx->pollfd_modify_lock);
-	if (r) {
-		usbi_dbg("someone else is modifying poll fds");
-		return 1;
-	}
-
-	r = usbi_mutex_trylock(&ctx->events_lock);
-	if (r)
-		return 1;
-
-	ctx->event_handler_active = 1;
-	return 0;
-}
-
-/** \ingroup poll
- * Acquire the event handling lock, blocking until successful acquisition if
- * it is contended. This lock is used to ensure that only one thread is
- * monitoring libusb event sources at any one time.
- *
- * You only need to use this lock if you are developing an application
- * which calls poll() or select() on libusb's file descriptors directly.
- * If you stick to libusb's event handling loop functions (e.g.
- * libusb_handle_events()) then you do not need to be concerned with this
- * locking.
- *
- * While holding this lock, you are trusted to actually be handling events.
- * If you are no longer handling events, you must call libusb_unlock_events()
- * as soon as possible.
- *
- * \param ctx the context to operate on, or NULL for the default context
- * \see \ref mtasync
- */
-void API_EXPORTED libusb_lock_events(libusb_context *ctx)
-{
-	USBI_GET_CONTEXT(ctx);
-	usbi_mutex_lock(&ctx->events_lock);
-	ctx->event_handler_active = 1;
-}
-
-/** \ingroup poll
- * Release the lock previously acquired with libusb_try_lock_events() or
- * libusb_lock_events(). Releasing this lock will wake up any threads blocked
- * on libusb_wait_for_event().
- *
- * \param ctx the context to operate on, or NULL for the default context
- * \see \ref mtasync
- */
-void API_EXPORTED libusb_unlock_events(libusb_context *ctx)
-{
-	USBI_GET_CONTEXT(ctx);
-	ctx->event_handler_active = 0;
-	usbi_mutex_unlock(&ctx->events_lock);
-
-	/* FIXME: perhaps we should be a bit more efficient by not broadcasting
-	 * the availability of the events lock when we are modifying pollfds
-	 * (check ctx->pollfd_modify)? */
-	usbi_mutex_lock(&ctx->event_waiters_lock);
-	usbi_cond_broadcast(&ctx->event_waiters_cond);
-	usbi_mutex_unlock(&ctx->event_waiters_lock);
-}
-
-/** \ingroup poll
- * Determine if it is still OK for this thread to be doing event handling.
- *
- * Sometimes, libusb needs to temporarily pause all event handlers, and this
- * is the function you should use before polling file descriptors to see if
- * this is the case.
- *
- * If this function instructs your thread to give up the events lock, you
- * should just continue the usual logic that is documented in \ref mtasync.
- * On the next iteration, your thread will fail to obtain the events lock,
- * and will hence become an event waiter.
- *
- * This function should be called while the events lock is held: you don't
- * need to worry about the results of this function if your thread is not
- * the current event handler.
- *
- * \param ctx the context to operate on, or NULL for the default context
- * \returns 1 if event handling can start or continue
- * \returns 0 if this thread must give up the events lock
- * \see \ref fullstory "Multi-threaded I/O: the full story"
- */
-int API_EXPORTED libusb_event_handling_ok(libusb_context *ctx)
-{
-	int r;
-	USBI_GET_CONTEXT(ctx);
-
-	/* is someone else waiting to modify poll fds? if so, don't let this thread
-	 * continue event handling */
-	usbi_mutex_lock(&ctx->pollfd_modify_lock);
-	r = ctx->pollfd_modify;
-	usbi_mutex_unlock(&ctx->pollfd_modify_lock);
-	if (r) {
-		usbi_dbg("someone else is modifying poll fds");
-		return 0;
-	}
-
-	return 1;
-}
-
-
-/** \ingroup poll
- * Determine if an active thread is handling events (i.e. if anyone is holding
- * the event handling lock).
- *
- * \param ctx the context to operate on, or NULL for the default context
- * \returns 1 if a thread is handling events
- * \returns 0 if there are no threads currently handling events
- * \see \ref mtasync
- */
-int API_EXPORTED libusb_event_handler_active(libusb_context *ctx)
-{
-	int r;
-	USBI_GET_CONTEXT(ctx);
-
-	/* is someone else waiting to modify poll fds? if so, don't let this thread
-	 * start event handling -- indicate that event handling is happening */
-	usbi_mutex_lock(&ctx->pollfd_modify_lock);
-	r = ctx->pollfd_modify;
-	usbi_mutex_unlock(&ctx->pollfd_modify_lock);
-	if (r) {
-		usbi_dbg("someone else is modifying poll fds");
-		return 1;
-	}
-
-	return ctx->event_handler_active;
-}
-
-/** \ingroup poll
- * Acquire the event waiters lock. This lock is designed to be obtained under
- * the situation where you want to be aware when events are completed, but
- * some other thread is event handling so calling libusb_handle_events() is not
- * allowed.
- *
- * You then obtain this lock, re-check that another thread is still handling
- * events, then call libusb_wait_for_event().
- *
- * You only need to use this lock if you are developing an application
- * which calls poll() or select() on libusb's file descriptors directly,
- * <b>and</b> may potentially be handling events from 2 threads simultaenously.
- * If you stick to libusb's event handling loop functions (e.g.
- * libusb_handle_events()) then you do not need to be concerned with this
- * locking.
- *
- * \param ctx the context to operate on, or NULL for the default context
- * \see \ref mtasync
- */
-void API_EXPORTED libusb_lock_event_waiters(libusb_context *ctx)
-{
-	USBI_GET_CONTEXT(ctx);
-	usbi_mutex_lock(&ctx->event_waiters_lock);
-}
-
-/** \ingroup poll
- * Release the event waiters lock.
- * \param ctx the context to operate on, or NULL for the default context
- * \see \ref mtasync
- */
-void API_EXPORTED libusb_unlock_event_waiters(libusb_context *ctx)
-{
-	USBI_GET_CONTEXT(ctx);
-	usbi_mutex_unlock(&ctx->event_waiters_lock);
-}
-
-/** \ingroup poll
- * Wait for another thread to signal completion of an event. Must be called
- * with the event waiters lock held, see libusb_lock_event_waiters().
- *
- * This function will block until any of the following conditions are met:
- * -# The timeout expires
- * -# A transfer completes
- * -# A thread releases the event handling lock through libusb_unlock_events()
- *
- * Condition 1 is obvious. Condition 2 unblocks your thread <em>after</em>
- * the callback for the transfer has completed. Condition 3 is important
- * because it means that the thread that was previously handling events is no
- * longer doing so, so if any events are to complete, another thread needs to
- * step up and start event handling.
- *
- * This function releases the event waiters lock before putting your thread
- * to sleep, and reacquires the lock as it is being woken up.
- *
- * \param ctx the context to operate on, or NULL for the default context
- * \param tv maximum timeout for this blocking function. A NULL value
- * indicates unlimited timeout.
- * \returns 0 after a transfer completes or another thread stops event handling
- * \returns 1 if the timeout expired
- * \see \ref mtasync
- */
-int API_EXPORTED libusb_wait_for_event(libusb_context *ctx, struct timeval *tv)
-{
-	struct timespec timeout;
-	int r;
-
-	USBI_GET_CONTEXT(ctx);
-	if (tv == NULL) {
-		usbi_cond_wait(&ctx->event_waiters_cond, &ctx->event_waiters_lock);
-		return 0;
-	}
-
-	r = usbi_backend->clock_gettime(USBI_CLOCK_REALTIME, &timeout);
-	if (r < 0) {
-		usbi_err(ctx, "failed to read realtime clock, error %d", errno);
-		return LIBUSB_ERROR_OTHER;
-	}
-
-	timeout.tv_sec += tv->tv_sec;
-	timeout.tv_nsec += tv->tv_usec * 1000;
-	if (timeout.tv_nsec > 1000000000) {
-		timeout.tv_nsec -= 1000000000;
-		timeout.tv_sec++;
-	}
-
-	r = usbi_cond_timedwait(&ctx->event_waiters_cond,
-		&ctx->event_waiters_lock, &timeout);
-	return (r == ETIMEDOUT);
-}
-
-static void handle_timeout(struct usbi_transfer *itransfer)
-{
-	struct libusb_transfer *transfer =
-		USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	int r;
-
-	itransfer->flags |= USBI_TRANSFER_TIMED_OUT;
-	r = libusb_cancel_transfer(transfer);
-	if (r < 0)
-		usbi_warn(TRANSFER_CTX(transfer),
-			"async cancel failed %d errno=%d", r, errno);
-}
-
-static int handle_timeouts_locked(struct libusb_context *ctx)
-{
-	int r;
-	struct timespec systime_ts;
-	struct timeval systime;
-	struct usbi_transfer *transfer;
-
-	if (list_empty(&ctx->flying_transfers))
-		return 0;
-
-	/* get current time */
-	r = usbi_backend->clock_gettime(USBI_CLOCK_MONOTONIC, &systime_ts);
-	if (r < 0)
-		return r;
-
-	TIMESPEC_TO_TIMEVAL(&systime, &systime_ts);
-
-	/* iterate through flying transfers list, finding all transfers that
-	 * have expired timeouts */
-	list_for_each_entry(transfer, &ctx->flying_transfers, list, struct usbi_transfer) {
-		struct timeval *cur_tv = &transfer->timeout;
-
-		/* if we've reached transfers of infinite timeout, we're all done */
-		if (!timerisset(cur_tv))
-			return 0;
-
-		/* ignore timeouts we've already handled */
-		if (transfer->flags & (USBI_TRANSFER_TIMED_OUT | USBI_TRANSFER_OS_HANDLES_TIMEOUT))
-			continue;
-
-		/* if transfer has non-expired timeout, nothing more to do */
-		if ((cur_tv->tv_sec > systime.tv_sec) ||
-				(cur_tv->tv_sec == systime.tv_sec &&
-					cur_tv->tv_usec > systime.tv_usec))
-			return 0;
-
-		/* otherwise, we've got an expired timeout to handle */
-		handle_timeout(transfer);
-	}
-	return 0;
-}
-
-static int handle_timeouts(struct libusb_context *ctx)
-{
-	int r;
-	USBI_GET_CONTEXT(ctx);
-	usbi_mutex_lock(&ctx->flying_transfers_lock);
-	r = handle_timeouts_locked(ctx);
-	usbi_mutex_unlock(&ctx->flying_transfers_lock);
-	return r;
-}
-
-#ifdef USBI_TIMERFD_AVAILABLE
-static int handle_timerfd_trigger(struct libusb_context *ctx)
-{
-	int r;
-
-	r = disarm_timerfd(ctx);
-	if (r < 0)
-		return r;
-
-	usbi_mutex_lock(&ctx->flying_transfers_lock);
-
-	/* process the timeout that just happened */
-	r = handle_timeouts_locked(ctx);
-	if (r < 0)
-		goto out;
-
-	/* arm for next timeout*/
-	r = arm_timerfd_for_next_timeout(ctx);
-
-out:
-	usbi_mutex_unlock(&ctx->flying_transfers_lock);
-	return r;
-}
-#endif
-
-/* do the actual event handling. assumes that no other thread is concurrently
- * doing the same thing. */
-static int handle_events(struct libusb_context *ctx, struct timeval *tv)
-{
-	int r;
-	struct usbi_pollfd *ipollfd;
-	POLL_NFDS_TYPE nfds = 0;
-	struct pollfd *fds;
-	int i = -1;
-	int timeout_ms;
-
-	usbi_mutex_lock(&ctx->pollfds_lock);
-	list_for_each_entry(ipollfd, &ctx->pollfds, list, struct usbi_pollfd)
-		nfds++;
-
-	/* TODO: malloc when number of fd's changes, not on every poll */
-	fds = malloc(sizeof(*fds) * nfds);
-	if (!fds) {
-		usbi_mutex_unlock(&ctx->pollfds_lock);
-		return LIBUSB_ERROR_NO_MEM;
-	}
-
-	list_for_each_entry(ipollfd, &ctx->pollfds, list, struct usbi_pollfd) {
-		struct libusb_pollfd *pollfd = &ipollfd->pollfd;
-		int fd = pollfd->fd;
-		i++;
-		fds[i].fd = fd;
-		fds[i].events = pollfd->events;
-		fds[i].revents = 0;
-	}
-	usbi_mutex_unlock(&ctx->pollfds_lock);
-
-	timeout_ms = (tv->tv_sec * 1000) + (tv->tv_usec / 1000);
-
-	/* round up to next millisecond */
-	if (tv->tv_usec % 1000)
-		timeout_ms++;
-
-	usbi_dbg("poll() %d fds with timeout in %dms", nfds, timeout_ms);
-	r = usbi_poll(fds, nfds, timeout_ms);
-	usbi_dbg("poll() returned %d", r);
-	if (r == 0) {
-		free(fds);
-		return handle_timeouts(ctx);
-	} else if (r == -1 && errno == EINTR) {
-		free(fds);
-		return LIBUSB_ERROR_INTERRUPTED;
-	} else if (r < 0) {
-		free(fds);
-		usbi_err(ctx, "poll failed %d err=%d\n", r, errno);
-		return LIBUSB_ERROR_IO;
-	}
-
-	/* fd[0] is always the ctrl pipe */
-	if (fds[0].revents) {
-		/* another thread wanted to interrupt event handling, and it succeeded!
-		 * handle any other events that cropped up at the same time, and
-		 * simply return */
-		usbi_dbg("caught a fish on the control pipe");
-
-		if (r == 1) {
-			r = 0;
-			goto handled;
-		} else {
-			/* prevent OS backend from trying to handle events on ctrl pipe */
-			fds[0].revents = 0;
-			r--;
-		}
-	}
-
-#ifdef USBI_TIMERFD_AVAILABLE
-	/* on timerfd configurations, fds[1] is the timerfd */
-	if (usbi_using_timerfd(ctx) && fds[1].revents) {
-		/* timerfd indicates that a timeout has expired */
-		int ret;
-		usbi_dbg("timerfd triggered");
-
-		ret = handle_timerfd_trigger(ctx);
-		if (ret < 0) {
-			/* return error code */
-			r = ret;
-			goto handled;
-		} else if (r == 1) {
-			/* no more active file descriptors, nothing more to do */
-			r = 0;
-			goto handled;
-		} else {
-			/* more events pending...
-			 * prevent OS backend from trying to handle events on timerfd */
-			fds[1].revents = 0;
-			r--;
-		}
-	}
-#endif
-
-	r = usbi_backend->handle_events(ctx, fds, nfds, r);
-	if (r)
-		usbi_err(ctx, "backend handle_events failed with error %d", r);
-
-handled:
-	free(fds);
-	return r;
-}
-
-/* returns the smallest of:
- *  1. timeout of next URB
- *  2. user-supplied timeout
- * returns 1 if there is an already-expired timeout, otherwise returns 0
- * and populates out
- */
-static int get_next_timeout(libusb_context *ctx, struct timeval *tv,
-	struct timeval *out)
-{
-	struct timeval timeout;
-	int r = libusb_get_next_timeout(ctx, &timeout);
-	if (r) {
-		/* timeout already expired? */
-		if (!timerisset(&timeout))
-			return 1;
-
-		/* choose the smallest of next URB timeout or user specified timeout */
-		if (timercmp(&timeout, tv, <))
-			*out = timeout;
-		else
-			*out = *tv;
-	} else {
-		*out = *tv;
-	}
-	return 0;
-}
-
-/** \ingroup poll
- * Handle any pending events.
- *
- * libusb determines "pending events" by checking if any timeouts have expired
- * and by checking the set of file descriptors for activity.
- *
- * If a zero timeval is passed, this function will handle any already-pending
- * events and then immediately return in non-blocking style.
- *
- * If a non-zero timeval is passed and no events are currently pending, this
- * function will block waiting for events to handle up until the specified
- * timeout. If an event arrives or a signal is raised, this function will
- * return early.
- *
- * If the parameter completed is not NULL then <em>after obtaining the event
- * handling lock</em> this function will return immediately if the integer
- * pointed to is not 0. This allows for race free waiting for the completion
- * of a specific transfer.
- *
- * \param ctx the context to operate on, or NULL for the default context
- * \param tv the maximum time to block waiting for events, or an all zero
- * timeval struct for non-blocking mode
- * \param completed pointer to completion integer to check, or NULL
- * \returns 0 on success, or a LIBUSB_ERROR code on failure
- * \see \ref mtasync
- */
-int API_EXPORTED libusb_handle_events_timeout_completed(libusb_context *ctx,
-	struct timeval *tv, int *completed)
-{
-	int r;
-	struct timeval poll_timeout;
-
-	USBI_GET_CONTEXT(ctx);
-	r = get_next_timeout(ctx, tv, &poll_timeout);
-	if (r) {
-		/* timeout already expired */
-		return handle_timeouts(ctx);
-	}
-
-retry:
-	if (libusb_try_lock_events(ctx) == 0) {
-		if (completed == NULL || !*completed) {
-			/* we obtained the event lock: do our own event handling */
-			usbi_dbg("doing our own event handling");
-			r = handle_events(ctx, &poll_timeout);
-		}
-		libusb_unlock_events(ctx);
-		return r;
-	}
-
-	/* another thread is doing event handling. wait for pthread events that
-	 * notify event completion. */
-	libusb_lock_event_waiters(ctx);
-
-	if (completed && *completed)
-		goto already_done;
-
-	if (!libusb_event_handler_active(ctx)) {
-		/* we hit a race: whoever was event handling earlier finished in the
-		 * time it took us to reach this point. try the cycle again. */
-		libusb_unlock_event_waiters(ctx);
-		usbi_dbg("event handler was active but went away, retrying");
-		goto retry;
-	}
-
-	usbi_dbg("another thread is doing event handling");
-	r = libusb_wait_for_event(ctx, &poll_timeout);
-
-already_done:
-	libusb_unlock_event_waiters(ctx);
-
-	if (r < 0)
-		return r;
-	else if (r == 1)
-		return handle_timeouts(ctx);
-	else
-		return 0;
-}
-
-/** \ingroup poll
- * Handle any pending events
- *
- * Like libusb_handle_events_timeout_completed(), but without the completed
- * parameter, calling this function is equivalent to calling
- * libusb_handle_events_timeout_completed() with a NULL completed parameter.
- *
- * This function is kept primarily for backwards compatibility.
- * All new code should call libusb_handle_events_completed() or
- * libusb_handle_events_timeout_completed() to avoid race conditions.
- *
- * \param ctx the context to operate on, or NULL for the default context
- * \param tv the maximum time to block waiting for events, or an all zero
- * timeval struct for non-blocking mode
- * \returns 0 on success, or a LIBUSB_ERROR code on failure
- */
-int API_EXPORTED libusb_handle_events_timeout(libusb_context *ctx,
-	struct timeval *tv)
-{
-	return libusb_handle_events_timeout_completed(ctx, tv, NULL);
-}
-
-/** \ingroup poll
- * Handle any pending events in blocking mode. There is currently a timeout
- * hardcoded at 60 seconds but we plan to make it unlimited in future. For
- * finer control over whether this function is blocking or non-blocking, or
- * for control over the timeout, use libusb_handle_events_timeout_completed()
- * instead.
- *
- * This function is kept primarily for backwards compatibility.
- * All new code should call libusb_handle_events_completed() or
- * libusb_handle_events_timeout_completed() to avoid race conditions.
- *
- * \param ctx the context to operate on, or NULL for the default context
- * \returns 0 on success, or a LIBUSB_ERROR code on failure
- */
-int API_EXPORTED libusb_handle_events(libusb_context *ctx)
-{
-	struct timeval tv;
-	tv.tv_sec = 60;
-	tv.tv_usec = 0;
-	return libusb_handle_events_timeout_completed(ctx, &tv, NULL);
-}
-
-/** \ingroup poll
- * Handle any pending events in blocking mode.
- *
- * Like libusb_handle_events(), with the addition of a completed parameter
- * to allow for race free waiting for the completion of a specific transfer.
- *
- * See libusb_handle_events_timeout_completed() for details on the completed
- * parameter.
- *
- * \param ctx the context to operate on, or NULL for the default context
- * \param completed pointer to completion integer to check, or NULL
- * \returns 0 on success, or a LIBUSB_ERROR code on failure
- * \see \ref mtasync
- */
-int API_EXPORTED libusb_handle_events_completed(libusb_context *ctx,
-	int *completed)
-{
-	struct timeval tv;
-	tv.tv_sec = 60;
-	tv.tv_usec = 0;
-	return libusb_handle_events_timeout_completed(ctx, &tv, completed);
-}
-
-/** \ingroup poll
- * Handle any pending events by polling file descriptors, without checking if
- * any other threads are already doing so. Must be called with the event lock
- * held, see libusb_lock_events().
- *
- * This function is designed to be called under the situation where you have
- * taken the event lock and are calling poll()/select() directly on libusb's
- * file descriptors (as opposed to using libusb_handle_events() or similar).
- * You detect events on libusb's descriptors, so you then call this function
- * with a zero timeout value (while still holding the event lock).
- *
- * \param ctx the context to operate on, or NULL for the default context
- * \param tv the maximum time to block waiting for events, or zero for
- * non-blocking mode
- * \returns 0 on success, or a LIBUSB_ERROR code on failure
- * \see \ref mtasync
- */
-int API_EXPORTED libusb_handle_events_locked(libusb_context *ctx,
-	struct timeval *tv)
-{
-	int r;
-	struct timeval poll_timeout;
-
-	USBI_GET_CONTEXT(ctx);
-	r = get_next_timeout(ctx, tv, &poll_timeout);
-	if (r) {
-		/* timeout already expired */
-		return handle_timeouts(ctx);
-	}
-
-	return handle_events(ctx, &poll_timeout);
-}
-
-/** \ingroup poll
- * Determines whether your application must apply special timing considerations
- * when monitoring libusb's file descriptors.
- *
- * This function is only useful for applications which retrieve and poll
- * libusb's file descriptors in their own main loop (\ref pollmain).
- *
- * Ordinarily, libusb's event handler needs to be called into at specific
- * moments in time (in addition to times when there is activity on the file
- * descriptor set). The usual approach is to use libusb_get_next_timeout()
- * to learn about when the next timeout occurs, and to adjust your
- * poll()/select() timeout accordingly so that you can make a call into the
- * library at that time.
- *
- * Some platforms supported by libusb do not come with this baggage - any
- * events relevant to timing will be represented by activity on the file
- * descriptor set, and libusb_get_next_timeout() will always return 0.
- * This function allows you to detect whether you are running on such a
- * platform.
- *
- * Since v1.0.5.
- *
- * \param ctx the context to operate on, or NULL for the default context
- * \returns 0 if you must call into libusb at times determined by
- * libusb_get_next_timeout(), or 1 if all timeout events are handled internally
- * or through regular activity on the file descriptors.
- * \see \ref pollmain "Polling libusb file descriptors for event handling"
- */
-int API_EXPORTED libusb_pollfds_handle_timeouts(libusb_context *ctx)
-{
-#if defined(USBI_TIMERFD_AVAILABLE)
-	USBI_GET_CONTEXT(ctx);
-	return usbi_using_timerfd(ctx);
-#else
-	(void)ctx;
-	return 0;
-#endif
-}
-
-/** \ingroup poll
- * Determine the next internal timeout that libusb needs to handle. You only
- * need to use this function if you are calling poll() or select() or similar
- * on libusb's file descriptors yourself - you do not need to use it if you
- * are calling libusb_handle_events() or a variant directly.
- *
- * You should call this function in your main loop in order to determine how
- * long to wait for select() or poll() to return results. libusb needs to be
- * called into at this timeout, so you should use it as an upper bound on
- * your select() or poll() call.
- *
- * When the timeout has expired, call into libusb_handle_events_timeout()
- * (perhaps in non-blocking mode) so that libusb can handle the timeout.
- *
- * This function may return 1 (success) and an all-zero timeval. If this is
- * the case, it indicates that libusb has a timeout that has already expired
- * so you should call libusb_handle_events_timeout() or similar immediately.
- * A return code of 0 indicates that there are no pending timeouts.
- *
- * On some platforms, this function will always returns 0 (no pending
- * timeouts). See \ref polltime.
- *
- * \param ctx the context to operate on, or NULL for the default context
- * \param tv output location for a relative time against the current
- * clock in which libusb must be called into in order to process timeout events
- * \returns 0 if there are no pending timeouts, 1 if a timeout was returned,
- * or LIBUSB_ERROR_OTHER on failure
- */
-int API_EXPORTED libusb_get_next_timeout(libusb_context *ctx,
-	struct timeval *tv)
-{
-	struct usbi_transfer *transfer;
-	struct timespec cur_ts;
-	struct timeval cur_tv;
-	struct timeval *next_timeout;
-	int r;
-	int found = 0;
-
-	USBI_GET_CONTEXT(ctx);
-	if (usbi_using_timerfd(ctx))
-		return 0;
-
-	usbi_mutex_lock(&ctx->flying_transfers_lock);
-	if (list_empty(&ctx->flying_transfers)) {
-		usbi_mutex_unlock(&ctx->flying_transfers_lock);
-		usbi_dbg("no URBs, no timeout!");
-		return 0;
-	}
-
-	/* find next transfer which hasn't already been processed as timed out */
-	list_for_each_entry(transfer, &ctx->flying_transfers, list, struct usbi_transfer) {
-		if (transfer->flags & (USBI_TRANSFER_TIMED_OUT | USBI_TRANSFER_OS_HANDLES_TIMEOUT))
-			continue;
-
-		/* no timeout for this transfer? */
-		if (!timerisset(&transfer->timeout))
-			continue;
-
-		found = 1;
-		break;
-	}
-	usbi_mutex_unlock(&ctx->flying_transfers_lock);
-
-	if (!found) {
-		usbi_dbg("no URB with timeout or all handled by OS; no timeout!");
-		return 0;
-	}
-
-	next_timeout = &transfer->timeout;
-
-	r = usbi_backend->clock_gettime(USBI_CLOCK_MONOTONIC, &cur_ts);
-	if (r < 0) {
-		usbi_err(ctx, "failed to read monotonic clock, errno=%d", errno);
-		return LIBUSB_ERROR_OTHER;
-	}
-	TIMESPEC_TO_TIMEVAL(&cur_tv, &cur_ts);
-
-	if (!timercmp(&cur_tv, next_timeout, <)) {
-		usbi_dbg("first timeout already expired");
-		timerclear(tv);
-	} else {
-		timersub(next_timeout, &cur_tv, tv);
-		usbi_dbg("next timeout in %d.%06ds", tv->tv_sec, tv->tv_usec);
-	}
-
-	return 1;
-}
-
-/** \ingroup poll
- * Register notification functions for file descriptor additions/removals.
- * These functions will be invoked for every new or removed file descriptor
- * that libusb uses as an event source.
- *
- * To remove notifiers, pass NULL values for the function pointers.
- *
- * Note that file descriptors may have been added even before you register
- * these notifiers (e.g. at libusb_init() time).
- *
- * Additionally, note that the removal notifier may be called during
- * libusb_exit() (e.g. when it is closing file descriptors that were opened
- * and added to the poll set at libusb_init() time). If you don't want this,
- * remove the notifiers immediately before calling libusb_exit().
- *
- * \param ctx the context to operate on, or NULL for the default context
- * \param added_cb pointer to function for addition notifications
- * \param removed_cb pointer to function for removal notifications
- * \param user_data User data to be passed back to callbacks (useful for
- * passing context information)
- */
-void API_EXPORTED libusb_set_pollfd_notifiers(libusb_context *ctx,
-	libusb_pollfd_added_cb added_cb, libusb_pollfd_removed_cb removed_cb,
-	void *user_data)
-{
-	USBI_GET_CONTEXT(ctx);
-	ctx->fd_added_cb = added_cb;
-	ctx->fd_removed_cb = removed_cb;
-	ctx->fd_cb_user_data = user_data;
-}
-
-/* Add a file descriptor to the list of file descriptors to be monitored.
- * events should be specified as a bitmask of events passed to poll(), e.g.
- * POLLIN and/or POLLOUT. */
-int usbi_add_pollfd(struct libusb_context *ctx, int fd, short events)
-{
-	struct usbi_pollfd *ipollfd = malloc(sizeof(*ipollfd));
-	if (!ipollfd)
-		return LIBUSB_ERROR_NO_MEM;
-
-	usbi_dbg("add fd %d events %d", fd, events);
-	ipollfd->pollfd.fd = fd;
-	ipollfd->pollfd.events = events;
-	usbi_mutex_lock(&ctx->pollfds_lock);
-	list_add_tail(&ipollfd->list, &ctx->pollfds);
-	usbi_mutex_unlock(&ctx->pollfds_lock);
-
-	if (ctx->fd_added_cb)
-		ctx->fd_added_cb(fd, events, ctx->fd_cb_user_data);
-	return 0;
-}
-
-/* Remove a file descriptor from the list of file descriptors to be polled. */
-void usbi_remove_pollfd(struct libusb_context *ctx, int fd)
-{
-	struct usbi_pollfd *ipollfd;
-	int found = 0;
-
-	usbi_dbg("remove fd %d", fd);
-	usbi_mutex_lock(&ctx->pollfds_lock);
-	list_for_each_entry(ipollfd, &ctx->pollfds, list, struct usbi_pollfd)
-		if (ipollfd->pollfd.fd == fd) {
-			found = 1;
-			break;
-		}
-
-	if (!found) {
-		usbi_dbg("couldn't find fd %d to remove", fd);
-		usbi_mutex_unlock(&ctx->pollfds_lock);
-		return;
-	}
-
-	list_del(&ipollfd->list);
-	usbi_mutex_unlock(&ctx->pollfds_lock);
-	free(ipollfd);
-	if (ctx->fd_removed_cb)
-		ctx->fd_removed_cb(fd, ctx->fd_cb_user_data);
-}
-
-/** \ingroup poll
- * Retrieve a list of file descriptors that should be polled by your main loop
- * as libusb event sources.
- *
- * The returned list is NULL-terminated and should be freed with free() when
- * done. The actual list contents must not be touched.
- *
- * As file descriptors are a Unix-specific concept, this function is not
- * available on Windows and will always return NULL.
- *
- * \param ctx the context to operate on, or NULL for the default context
- * \returns a NULL-terminated list of libusb_pollfd structures
- * \returns NULL on error
- * \returns NULL on platforms where the functionality is not available
- */
-DEFAULT_VISIBILITY
-const struct libusb_pollfd ** LIBUSB_CALL libusb_get_pollfds(
-	libusb_context *ctx)
-{
-#ifndef OS_WINDOWS
-	struct libusb_pollfd **ret = NULL;
-	struct usbi_pollfd *ipollfd;
-	size_t i = 0;
-	size_t cnt = 0;
-	USBI_GET_CONTEXT(ctx);
-
-	usbi_mutex_lock(&ctx->pollfds_lock);
-	list_for_each_entry(ipollfd, &ctx->pollfds, list, struct usbi_pollfd)
-		cnt++;
-
-	ret = calloc(cnt + 1, sizeof(struct libusb_pollfd *));
-	if (!ret)
-		goto out;
-
-	list_for_each_entry(ipollfd, &ctx->pollfds, list, struct usbi_pollfd)
-		ret[i++] = (struct libusb_pollfd *) ipollfd;
-	ret[cnt] = NULL;
-
-out:
-	usbi_mutex_unlock(&ctx->pollfds_lock);
-	return (const struct libusb_pollfd **) ret;
-#else
-	return NULL;
-#endif
-}
-
-/* Backends call this from handle_events to report disconnection of a device.
- * The transfers get cancelled appropriately.
- */
-void usbi_handle_disconnect(struct libusb_device_handle *handle)
-{
-	struct usbi_transfer *cur;
-	struct usbi_transfer *to_cancel;
-
-	usbi_dbg("device %d.%d",
-		handle->dev->bus_number, handle->dev->device_address);
-
-	/* terminate all pending transfers with the LIBUSB_TRANSFER_NO_DEVICE
-	 * status code.
-	 *
-	 * this is a bit tricky because:
-	 * 1. we can't do transfer completion while holding flying_transfers_lock
-	 * 2. the transfers list can change underneath us - if we were to build a
-	 *    list of transfers to complete (while holding look), the situation
-	 *    might be different by the time we come to free them
-	 *
-	 * so we resort to a loop-based approach as below
-	 * FIXME: is this still potentially racy?
-	 */
-
-	while (1) {
-		usbi_mutex_lock(&HANDLE_CTX(handle)->flying_transfers_lock);
-		to_cancel = NULL;
-		list_for_each_entry(cur, &HANDLE_CTX(handle)->flying_transfers, list, struct usbi_transfer)
-			if (USBI_TRANSFER_TO_LIBUSB_TRANSFER(cur)->dev_handle == handle) {
-				to_cancel = cur;
-				break;
-			}
-		usbi_mutex_unlock(&HANDLE_CTX(handle)->flying_transfers_lock);
-
-		if (!to_cancel)
-			break;
-
-		usbi_backend->clear_transfer_priv(to_cancel);
-		usbi_handle_transfer_completion(to_cancel, LIBUSB_TRANSFER_NO_DEVICE);
-	}
-
-}
diff --git a/third_party/libusb/libusb/libusb-1.0.def b/third_party/libusb/libusb/libusb-1.0.def
deleted file mode 100644
index 96abd17..0000000
--- a/third_party/libusb/libusb/libusb-1.0.def
+++ /dev/null
@@ -1,118 +0,0 @@
-LIBRARY
-EXPORTS
-  libusb_alloc_transfer
-  libusb_alloc_transfer@4 = libusb_alloc_transfer
-  libusb_attach_kernel_driver
-  libusb_attach_kernel_driver@8 = libusb_attach_kernel_driver
-  libusb_bulk_transfer
-  libusb_bulk_transfer@24 = libusb_bulk_transfer
-  libusb_cancel_transfer
-  libusb_cancel_transfer@4 = libusb_cancel_transfer
-  libusb_claim_interface
-  libusb_claim_interface@8 = libusb_claim_interface
-  libusb_clear_halt
-  libusb_clear_halt@8 = libusb_clear_halt
-  libusb_close
-  libusb_close@4 = libusb_close
-  libusb_control_transfer
-  libusb_control_transfer@32 = libusb_control_transfer
-  libusb_detach_kernel_driver
-  libusb_detach_kernel_driver@8 = libusb_detach_kernel_driver
-  libusb_error_name
-  libusb_error_name@4 = libusb_error_name
-  libusb_event_handler_active
-  libusb_event_handler_active@4 = libusb_event_handler_active
-  libusb_event_handling_ok
-  libusb_event_handling_ok@4 = libusb_event_handling_ok
-  libusb_exit
-  libusb_exit@4 = libusb_exit
-  libusb_free_config_descriptor
-  libusb_free_config_descriptor@4 = libusb_free_config_descriptor
-  libusb_free_device_list
-  libusb_free_device_list@8 = libusb_free_device_list
-  libusb_free_transfer
-  libusb_free_transfer@4 = libusb_free_transfer
-  libusb_get_active_config_descriptor
-  libusb_get_active_config_descriptor@8 = libusb_get_active_config_descriptor
-  libusb_get_bus_number
-  libusb_get_bus_number@4 = libusb_get_bus_number
-  libusb_get_config_descriptor
-  libusb_get_config_descriptor@12 = libusb_get_config_descriptor
-  libusb_get_config_descriptor_by_value
-  libusb_get_config_descriptor_by_value@12 = libusb_get_config_descriptor_by_value
-  libusb_get_configuration
-  libusb_get_configuration@8 = libusb_get_configuration
-  libusb_get_device
-  libusb_get_device@4 = libusb_get_device
-  libusb_get_device_address
-  libusb_get_device_address@4 = libusb_get_device_address
-  libusb_get_device_descriptor
-  libusb_get_device_descriptor@8 = libusb_get_device_descriptor
-  libusb_get_device_list
-  libusb_get_device_list@8 = libusb_get_device_list
-  libusb_get_device_speed
-  libusb_get_device_speed@4 = libusb_get_device_speed
-  libusb_get_max_iso_packet_size
-  libusb_get_max_iso_packet_size@8 = libusb_get_max_iso_packet_size
-  libusb_get_max_packet_size
-  libusb_get_max_packet_size@8 = libusb_get_max_packet_size
-  libusb_get_next_timeout
-  libusb_get_next_timeout@8 = libusb_get_next_timeout
-  libusb_get_pollfds
-  libusb_get_pollfds@4 = libusb_get_pollfds
-  libusb_get_string_descriptor_ascii
-  libusb_get_string_descriptor_ascii@16 = libusb_get_string_descriptor_ascii
-  libusb_handle_events
-  libusb_handle_events@4 = libusb_handle_events
-  libusb_handle_events_completed
-  libusb_handle_events_completed@8 = libusb_handle_events_completed
-  libusb_handle_events_locked
-  libusb_handle_events_locked@8 = libusb_handle_events_locked
-  libusb_handle_events_timeout
-  libusb_handle_events_timeout@8 = libusb_handle_events_timeout
-  libusb_handle_events_timeout_completed
-  libusb_handle_events_timeout_completed@12 = libusb_handle_events_timeout_completed
-  libusb_has_capability
-  libusb_has_capability@4 = libusb_has_capability
-  libusb_init
-  libusb_init@4 = libusb_init
-  libusb_interrupt_transfer
-  libusb_interrupt_transfer@24 = libusb_interrupt_transfer
-  libusb_kernel_driver_active
-  libusb_kernel_driver_active@8 = libusb_kernel_driver_active
-  libusb_lock_event_waiters
-  libusb_lock_event_waiters@4 = libusb_lock_event_waiters
-  libusb_lock_events
-  libusb_lock_events@4 = libusb_lock_events
-  libusb_open
-  libusb_open@8 = libusb_open
-  libusb_open_device_with_vid_pid
-  libusb_open_device_with_vid_pid@12 = libusb_open_device_with_vid_pid
-  libusb_pollfds_handle_timeouts
-  libusb_pollfds_handle_timeouts@4 = libusb_pollfds_handle_timeouts
-  libusb_ref_device
-  libusb_ref_device@4 = libusb_ref_device
-  libusb_release_interface
-  libusb_release_interface@8 = libusb_release_interface
-  libusb_reset_device
-  libusb_reset_device@4 = libusb_reset_device
-  libusb_set_configuration
-  libusb_set_configuration@8 = libusb_set_configuration
-  libusb_set_debug
-  libusb_set_debug@8 = libusb_set_debug
-  libusb_set_interface_alt_setting
-  libusb_set_interface_alt_setting@12 = libusb_set_interface_alt_setting
-  libusb_set_pollfd_notifiers
-  libusb_set_pollfd_notifiers@16 = libusb_set_pollfd_notifiers
-  libusb_submit_transfer
-  libusb_submit_transfer@4 = libusb_submit_transfer
-  libusb_try_lock_events
-  libusb_try_lock_events@4 = libusb_try_lock_events
-  libusb_unlock_event_waiters
-  libusb_unlock_event_waiters@4 = libusb_unlock_event_waiters
-  libusb_unlock_events
-  libusb_unlock_events@4 = libusb_unlock_events
-  libusb_unref_device
-  libusb_unref_device@4 = libusb_unref_device
-  libusb_wait_for_event
-  libusb_wait_for_event@8 = libusb_wait_for_event
diff --git a/third_party/libusb/libusb/libusb-1.0.rc b/third_party/libusb/libusb/libusb-1.0.rc
deleted file mode 100644
index 0171f17..0000000
--- a/third_party/libusb/libusb/libusb-1.0.rc
+++ /dev/null
@@ -1,60 +0,0 @@
-/*
- * For Windows: input this file to the Resoure Compiler to produce a binary
- * .res file. This is then embedded in the resultant library (like any other
- * compilation object).
- * The information can then be queried using standard APIs and can also be
- * viewed with utilities such as Windows Explorer.
- */
-#include "winresrc.h"
-
-#include "version.h"
-#ifndef LIBUSB_VERSIONSTRING
-#define LU_STR(s) #s
-#define LU_XSTR(s) LU_STR(s)
-#if LIBUSB_NANO > 0
-#define LIBUSB_VERSIONSTRING \
-	LU_XSTR(LIBUSB_MAJOR) "." LU_XSTR(LIBUSB_MINOR) "." \
-	LU_XSTR(LIBUSB_MICRO) "." LU_XSTR(LIBUSB_NANO) LIBUSB_RC "\0"
-#else
-#define LIBUSB_VERSIONSTRING \
-	LU_XSTR(LIBUSB_MAJOR) "." LU_XSTR(LIBUSB_MINOR) "." \
-	LU_XSTR(LIBUSB_MICRO) LIBUSB_RC "\0"
-#endif
-#endif
-
-VS_VERSION_INFO VERSIONINFO
- FILEVERSION LIBUSB_MAJOR,LIBUSB_MINOR,LIBUSB_MICRO,LIBUSB_NANO
- PRODUCTVERSION LIBUSB_MAJOR,LIBUSB_MINOR,LIBUSB_MICRO,LIBUSB_NANO
- FILEFLAGSMASK 0x3fL
-#ifdef _DEBUG
- FILEFLAGS 0x1L
-#else
- FILEFLAGS 0x0L
-#endif
- FILEOS 0x40004L
- FILETYPE 0x2L
- FILESUBTYPE 0x0L
-BEGIN
-	BLOCK "StringFileInfo"
-	BEGIN
-		BLOCK "040904b0"
-		BEGIN
-			VALUE "Comments", "\0"
-			VALUE "CompanyName", "libusb.org\0"
-			VALUE "FileDescription", "C library for writing portable USB drivers in userspace\0"
-			VALUE "FileVersion", LIBUSB_VERSIONSTRING
-			VALUE "InternalName", "libusb\0"
-			VALUE "LegalCopyright", "See individual source files, GNU LGPL v2.1 or later.\0"
-			VALUE "LegalTrademarks", "http://www.gnu.org/licenses/lgpl-2.1.html\0"
-			VALUE "OriginalFilename", "libusb-1.0.dll\0"
-			VALUE "PrivateBuild", "\0"
-			VALUE "ProductName", "libusb-1.0\0"
-			VALUE "ProductVersion", LIBUSB_VERSIONSTRING
-			VALUE "SpecialBuild", "\0"
-		END
-	END
-	BLOCK "VarFileInfo"
-	BEGIN
-		VALUE "Translation", 0x409, 1200
-	END
-END
diff --git a/third_party/libusb/libusb/libusb.h b/third_party/libusb/libusb/libusb.h
deleted file mode 100644
index de2d050..0000000
--- a/third_party/libusb/libusb/libusb.h
+++ /dev/null
@@ -1,1394 +0,0 @@
-/*
- * Public libusb header file
- * Copyright (C) 2007-2008 Daniel Drake <dsd@gentoo.org>
- * Copyright (c) 2001 Johannes Erdfelt <johannes@erdfelt.com>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#ifndef LIBUSB_H
-#define LIBUSB_H
-
-#ifdef _MSC_VER
-/* on MS environments, the inline keyword is available in C++ only */
-#define inline __inline
-/* ssize_t is also not available (copy/paste from MinGW) */
-#ifndef _SSIZE_T_DEFINED
-#define _SSIZE_T_DEFINED
-#undef ssize_t
-#ifdef _WIN64
-  typedef __int64 ssize_t;
-#else
-  typedef int ssize_t;
-#endif /* _WIN64 */
-#endif /* _SSIZE_T_DEFINED */
-#endif /* _MSC_VER */
-
-/* stdint.h is also not usually available on MS */
-#if defined(_MSC_VER) && (_MSC_VER < 1600) && (!defined(_STDINT)) && (!defined(_STDINT_H))
-typedef unsigned __int8   uint8_t;
-typedef unsigned __int16  uint16_t;
-typedef unsigned __int32  uint32_t;
-#else
-#include <stdint.h>
-#endif
-
-#include <sys/types.h>
-#include <time.h>
-#include <limits.h>
-
-#if defined(__linux) || defined(__APPLE__) || defined(__CYGWIN__)
-#include <sys/time.h>
-#endif
-
-/* 'interface' might be defined as a macro on Windows, so we need to
- * undefine it so as not to break the current libusb API, because
- * libusb_config_descriptor has an 'interface' member
- * As this can be problematic if you include windows.h after libusb.h
- * in your sources, we force windows.h to be included first. */
-#if defined(_WIN32) || defined(__CYGWIN__)
-#include <windows.h>
-#if defined(interface)
-#undef interface
-#endif
-#endif
-
-/** \def LIBUSB_CALL
- * \ingroup misc
- * libusb's Windows calling convention.
- *
- * Under Windows, the selection of available compilers and configurations
- * means that, unlike other platforms, there is not <em>one true calling
- * convention</em> (calling convention: the manner in which parameters are
- * passed to funcions in the generated assembly code).
- *
- * Matching the Windows API itself, libusb uses the WINAPI convention (which
- * translates to the <tt>stdcall</tt> convention) and guarantees that the
- * library is compiled in this way. The public header file also includes
- * appropriate annotations so that your own software will use the right
- * convention, even if another convention is being used by default within
- * your codebase.
- *
- * The one consideration that you must apply in your software is to mark
- * all functions which you use as libusb callbacks with this LIBUSB_CALL
- * annotation, so that they too get compiled for the correct calling
- * convention.
- *
- * On non-Windows operating systems, this macro is defined as nothing. This
- * means that you can apply it to your code without worrying about
- * cross-platform compatibility.
- */
-/* LIBUSB_CALL must be defined on both definition and declaration of libusb
- * functions. You'd think that declaration would be enough, but cygwin will
- * complain about conflicting types unless both are marked this way.
- * The placement of this macro is important too; it must appear after the
- * return type, before the function name. See internal documentation for
- * API_EXPORTED.
- */
-#if defined(_WIN32) || defined(__CYGWIN__)
-#define LIBUSB_CALL WINAPI
-#else
-#define LIBUSB_CALL
-#endif
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/** \def libusb_cpu_to_le16
- * \ingroup misc
- * Convert a 16-bit value from host-endian to little-endian format. On
- * little endian systems, this function does nothing. On big endian systems,
- * the bytes are swapped.
- * \param x the host-endian value to convert
- * \returns the value in little-endian byte order
- */
-static inline uint16_t libusb_cpu_to_le16(const uint16_t x)
-{
-	union {
-		uint8_t  b8[2];
-		uint16_t b16;
-	} _tmp;
-	_tmp.b8[1] = x >> 8;
-	_tmp.b8[0] = x & 0xff;
-	return _tmp.b16;
-}
-
-/** \def libusb_le16_to_cpu
- * \ingroup misc
- * Convert a 16-bit value from little-endian to host-endian format. On
- * little endian systems, this function does nothing. On big endian systems,
- * the bytes are swapped.
- * \param x the little-endian value to convert
- * \returns the value in host-endian byte order
- */
-#define libusb_le16_to_cpu libusb_cpu_to_le16
-
-/* standard USB stuff */
-
-/** \ingroup desc
- * Device and/or Interface Class codes */
-enum libusb_class_code {
-	/** In the context of a \ref libusb_device_descriptor "device descriptor",
-	 * this bDeviceClass value indicates that each interface specifies its
-	 * own class information and all interfaces operate independently.
-	 */
-	LIBUSB_CLASS_PER_INTERFACE = 0,
-
-	/** Audio class */
-	LIBUSB_CLASS_AUDIO = 1,
-
-	/** Communications class */
-	LIBUSB_CLASS_COMM = 2,
-
-	/** Human Interface Device class */
-	LIBUSB_CLASS_HID = 3,
-
-	/** Physical */
-	LIBUSB_CLASS_PHYSICAL = 5,
-
-	/** Printer class */
-	LIBUSB_CLASS_PRINTER = 7,
-
-	/** Image class */
-	LIBUSB_CLASS_PTP = 6, /* legacy name from libusb-0.1 usb.h */
-	LIBUSB_CLASS_IMAGE = 6,
-
-	/** Mass storage class */
-	LIBUSB_CLASS_MASS_STORAGE = 8,
-
-	/** Hub class */
-	LIBUSB_CLASS_HUB = 9,
-
-	/** Data class */
-	LIBUSB_CLASS_DATA = 10,
-
-	/** Smart Card */
-	LIBUSB_CLASS_SMART_CARD = 0x0b,
-
-	/** Content Security */
-	LIBUSB_CLASS_CONTENT_SECURITY = 0x0d,
-
-	/** Video */
-	LIBUSB_CLASS_VIDEO = 0x0e,
-
-	/** Personal Healthcare */
-	LIBUSB_CLASS_PERSONAL_HEALTHCARE = 0x0f,
-
-	/** Diagnostic Device */
-	LIBUSB_CLASS_DIAGNOSTIC_DEVICE = 0xdc,
-
-	/** Wireless class */
-	LIBUSB_CLASS_WIRELESS = 0xe0,
-
-	/** Application class */
-	LIBUSB_CLASS_APPLICATION = 0xfe,
-
-	/** Class is vendor-specific */
-	LIBUSB_CLASS_VENDOR_SPEC = 0xff
-};
-
-/** \ingroup desc
- * Descriptor types as defined by the USB specification. */
-enum libusb_descriptor_type {
-	/** Device descriptor. See libusb_device_descriptor. */
-	LIBUSB_DT_DEVICE = 0x01,
-
-	/** Configuration descriptor. See libusb_config_descriptor. */
-	LIBUSB_DT_CONFIG = 0x02,
-
-	/** String descriptor */
-	LIBUSB_DT_STRING = 0x03,
-
-	/** Interface descriptor. See libusb_interface_descriptor. */
-	LIBUSB_DT_INTERFACE = 0x04,
-
-	/** Endpoint descriptor. See libusb_endpoint_descriptor. */
-	LIBUSB_DT_ENDPOINT = 0x05,
-
-	/** HID descriptor */
-	LIBUSB_DT_HID = 0x21,
-
-	/** HID report descriptor */
-	LIBUSB_DT_REPORT = 0x22,
-
-	/** Physical descriptor */
-	LIBUSB_DT_PHYSICAL = 0x23,
-
-	/** Hub descriptor */
-	LIBUSB_DT_HUB = 0x29
-};
-
-/* Descriptor sizes per descriptor type */
-#define LIBUSB_DT_DEVICE_SIZE			18
-#define LIBUSB_DT_CONFIG_SIZE			9
-#define LIBUSB_DT_INTERFACE_SIZE		9
-#define LIBUSB_DT_ENDPOINT_SIZE		7
-#define LIBUSB_DT_ENDPOINT_AUDIO_SIZE	9	/* Audio extension */
-#define LIBUSB_DT_HUB_NONVAR_SIZE		7
-
-#define LIBUSB_ENDPOINT_ADDRESS_MASK	0x0f    /* in bEndpointAddress */
-#define LIBUSB_ENDPOINT_DIR_MASK		0x80
-
-/** \ingroup desc
- * Endpoint direction. Values for bit 7 of the
- * \ref libusb_endpoint_descriptor::bEndpointAddress "endpoint address" scheme.
- */
-enum libusb_endpoint_direction {
-	/** In: device-to-host */
-	LIBUSB_ENDPOINT_IN = 0x80,
-
-	/** Out: host-to-device */
-	LIBUSB_ENDPOINT_OUT = 0x00
-};
-
-#define LIBUSB_TRANSFER_TYPE_MASK			0x03    /* in bmAttributes */
-
-/** \ingroup desc
- * Endpoint transfer type. Values for bits 0:1 of the
- * \ref libusb_endpoint_descriptor::bmAttributes "endpoint attributes" field.
- */
-enum libusb_transfer_type {
-	/** Control endpoint */
-	LIBUSB_TRANSFER_TYPE_CONTROL = 0,
-
-	/** Isochronous endpoint */
-	LIBUSB_TRANSFER_TYPE_ISOCHRONOUS = 1,
-
-	/** Bulk endpoint */
-	LIBUSB_TRANSFER_TYPE_BULK = 2,
-
-	/** Interrupt endpoint */
-	LIBUSB_TRANSFER_TYPE_INTERRUPT = 3
-};
-
-/** \ingroup misc
- * Standard requests, as defined in table 9-3 of the USB2 specifications */
-enum libusb_standard_request {
-	/** Request status of the specific recipient */
-	LIBUSB_REQUEST_GET_STATUS = 0x00,
-
-	/** Clear or disable a specific feature */
-	LIBUSB_REQUEST_CLEAR_FEATURE = 0x01,
-
-	/* 0x02 is reserved */
-
-	/** Set or enable a specific feature */
-	LIBUSB_REQUEST_SET_FEATURE = 0x03,
-
-	/* 0x04 is reserved */
-
-	/** Set device address for all future accesses */
-	LIBUSB_REQUEST_SET_ADDRESS = 0x05,
-
-	/** Get the specified descriptor */
-	LIBUSB_REQUEST_GET_DESCRIPTOR = 0x06,
-
-	/** Used to update existing descriptors or add new descriptors */
-	LIBUSB_REQUEST_SET_DESCRIPTOR = 0x07,
-
-	/** Get the current device configuration value */
-	LIBUSB_REQUEST_GET_CONFIGURATION = 0x08,
-
-	/** Set device configuration */
-	LIBUSB_REQUEST_SET_CONFIGURATION = 0x09,
-
-	/** Return the selected alternate setting for the specified interface */
-	LIBUSB_REQUEST_GET_INTERFACE = 0x0A,
-
-	/** Select an alternate interface for the specified interface */
-	LIBUSB_REQUEST_SET_INTERFACE = 0x0B,
-
-	/** Set then report an endpoint's synchronization frame */
-	LIBUSB_REQUEST_SYNCH_FRAME = 0x0C
-};
-
-/** \ingroup misc
- * Request type bits of the
- * \ref libusb_control_setup::bmRequestType "bmRequestType" field in control
- * transfers. */
-enum libusb_request_type {
-	/** Standard */
-	LIBUSB_REQUEST_TYPE_STANDARD = (0x00 << 5),
-
-	/** Class */
-	LIBUSB_REQUEST_TYPE_CLASS = (0x01 << 5),
-
-	/** Vendor */
-	LIBUSB_REQUEST_TYPE_VENDOR = (0x02 << 5),
-
-	/** Reserved */
-	LIBUSB_REQUEST_TYPE_RESERVED = (0x03 << 5)
-};
-
-/** \ingroup misc
- * Recipient bits of the
- * \ref libusb_control_setup::bmRequestType "bmRequestType" field in control
- * transfers. Values 4 through 31 are reserved. */
-enum libusb_request_recipient {
-	/** Device */
-	LIBUSB_RECIPIENT_DEVICE = 0x00,
-
-	/** Interface */
-	LIBUSB_RECIPIENT_INTERFACE = 0x01,
-
-	/** Endpoint */
-	LIBUSB_RECIPIENT_ENDPOINT = 0x02,
-
-	/** Other */
-	LIBUSB_RECIPIENT_OTHER = 0x03
-};
-
-#define LIBUSB_ISO_SYNC_TYPE_MASK		0x0C
-
-/** \ingroup desc
- * Synchronization type for isochronous endpoints. Values for bits 2:3 of the
- * \ref libusb_endpoint_descriptor::bmAttributes "bmAttributes" field in
- * libusb_endpoint_descriptor.
- */
-enum libusb_iso_sync_type {
-	/** No synchronization */
-	LIBUSB_ISO_SYNC_TYPE_NONE = 0,
-
-	/** Asynchronous */
-	LIBUSB_ISO_SYNC_TYPE_ASYNC = 1,
-
-	/** Adaptive */
-	LIBUSB_ISO_SYNC_TYPE_ADAPTIVE = 2,
-
-	/** Synchronous */
-	LIBUSB_ISO_SYNC_TYPE_SYNC = 3
-};
-
-#define LIBUSB_ISO_USAGE_TYPE_MASK 0x30
-
-/** \ingroup desc
- * Usage type for isochronous endpoints. Values for bits 4:5 of the
- * \ref libusb_endpoint_descriptor::bmAttributes "bmAttributes" field in
- * libusb_endpoint_descriptor.
- */
-enum libusb_iso_usage_type {
-	/** Data endpoint */
-	LIBUSB_ISO_USAGE_TYPE_DATA = 0,
-
-	/** Feedback endpoint */
-	LIBUSB_ISO_USAGE_TYPE_FEEDBACK = 1,
-
-	/** Implicit feedback Data endpoint */
-	LIBUSB_ISO_USAGE_TYPE_IMPLICIT = 2
-};
-
-/** \ingroup desc
- * A structure representing the standard USB device descriptor. This
- * descriptor is documented in section 9.6.1 of the USB 2.0 specification.
- * All multiple-byte fields are represented in host-endian format.
- */
-struct libusb_device_descriptor {
-	/** Size of this descriptor (in bytes) */
-	uint8_t  bLength;
-
-	/** Descriptor type. Will have value
-	 * \ref libusb_descriptor_type::LIBUSB_DT_DEVICE LIBUSB_DT_DEVICE in this
-	 * context. */
-	uint8_t  bDescriptorType;
-
-	/** USB specification release number in binary-coded decimal. A value of
-	 * 0x0200 indicates USB 2.0, 0x0110 indicates USB 1.1, etc. */
-	uint16_t bcdUSB;
-
-	/** USB-IF class code for the device. See \ref libusb_class_code. */
-	uint8_t  bDeviceClass;
-
-	/** USB-IF subclass code for the device, qualified by the bDeviceClass
-	 * value */
-	uint8_t  bDeviceSubClass;
-
-	/** USB-IF protocol code for the device, qualified by the bDeviceClass and
-	 * bDeviceSubClass values */
-	uint8_t  bDeviceProtocol;
-
-	/** Maximum packet size for endpoint 0 */
-	uint8_t  bMaxPacketSize0;
-
-	/** USB-IF vendor ID */
-	uint16_t idVendor;
-
-	/** USB-IF product ID */
-	uint16_t idProduct;
-
-	/** Device release number in binary-coded decimal */
-	uint16_t bcdDevice;
-
-	/** Index of string descriptor describing manufacturer */
-	uint8_t  iManufacturer;
-
-	/** Index of string descriptor describing product */
-	uint8_t  iProduct;
-
-	/** Index of string descriptor containing device serial number */
-	uint8_t  iSerialNumber;
-
-	/** Number of possible configurations */
-	uint8_t  bNumConfigurations;
-};
-
-/** \ingroup desc
- * A structure representing the standard USB endpoint descriptor. This
- * descriptor is documented in section 9.6.3 of the USB 2.0 specification.
- * All multiple-byte fields are represented in host-endian format.
- */
-struct libusb_endpoint_descriptor {
-	/** Size of this descriptor (in bytes) */
-	uint8_t  bLength;
-
-	/** Descriptor type. Will have value
-	 * \ref libusb_descriptor_type::LIBUSB_DT_ENDPOINT LIBUSB_DT_ENDPOINT in
-	 * this context. */
-	uint8_t  bDescriptorType;
-
-	/** The address of the endpoint described by this descriptor. Bits 0:3 are
-	 * the endpoint number. Bits 4:6 are reserved. Bit 7 indicates direction,
-	 * see \ref libusb_endpoint_direction.
-	 */
-	uint8_t  bEndpointAddress;
-
-	/** Attributes which apply to the endpoint when it is configured using
-	 * the bConfigurationValue. Bits 0:1 determine the transfer type and
-	 * correspond to \ref libusb_transfer_type. Bits 2:3 are only used for
-	 * isochronous endpoints and correspond to \ref libusb_iso_sync_type.
-	 * Bits 4:5 are also only used for isochronous endpoints and correspond to
-	 * \ref libusb_iso_usage_type. Bits 6:7 are reserved.
-	 */
-	uint8_t  bmAttributes;
-
-	/** Maximum packet size this endpoint is capable of sending/receiving. */
-	uint16_t wMaxPacketSize;
-
-	/** Interval for polling endpoint for data transfers. */
-	uint8_t  bInterval;
-
-	/** For audio devices only: the rate at which synchronization feedback
-	 * is provided. */
-	uint8_t  bRefresh;
-
-	/** For audio devices only: the address if the synch endpoint */
-	uint8_t  bSynchAddress;
-
-	/** Extra descriptors. If libusb encounters unknown endpoint descriptors,
-	 * it will store them here, should you wish to parse them. */
-	const unsigned char *extra;
-
-	/** Length of the extra descriptors, in bytes. */
-	int extra_length;
-};
-
-/** \ingroup desc
- * A structure representing the standard USB interface descriptor. This
- * descriptor is documented in section 9.6.5 of the USB 2.0 specification.
- * All multiple-byte fields are represented in host-endian format.
- */
-struct libusb_interface_descriptor {
-	/** Size of this descriptor (in bytes) */
-	uint8_t  bLength;
-
-	/** Descriptor type. Will have value
-	 * \ref libusb_descriptor_type::LIBUSB_DT_INTERFACE LIBUSB_DT_INTERFACE
-	 * in this context. */
-	uint8_t  bDescriptorType;
-
-	/** Number of this interface */
-	uint8_t  bInterfaceNumber;
-
-	/** Value used to select this alternate setting for this interface */
-	uint8_t  bAlternateSetting;
-
-	/** Number of endpoints used by this interface (excluding the control
-	 * endpoint). */
-	uint8_t  bNumEndpoints;
-
-	/** USB-IF class code for this interface. See \ref libusb_class_code. */
-	uint8_t  bInterfaceClass;
-
-	/** USB-IF subclass code for this interface, qualified by the
-	 * bInterfaceClass value */
-	uint8_t  bInterfaceSubClass;
-
-	/** USB-IF protocol code for this interface, qualified by the
-	 * bInterfaceClass and bInterfaceSubClass values */
-	uint8_t  bInterfaceProtocol;
-
-	/** Index of string descriptor describing this interface */
-	uint8_t  iInterface;
-
-	/** Array of endpoint descriptors. This length of this array is determined
-	 * by the bNumEndpoints field. */
-	const struct libusb_endpoint_descriptor *endpoint;
-
-	/** Extra descriptors. If libusb encounters unknown interface descriptors,
-	 * it will store them here, should you wish to parse them. */
-	const unsigned char *extra;
-
-	/** Length of the extra descriptors, in bytes. */
-	int extra_length;
-};
-
-/** \ingroup desc
- * A collection of alternate settings for a particular USB interface.
- */
-struct libusb_interface {
-	/** Array of interface descriptors. The length of this array is determined
-	 * by the num_altsetting field. */
-	const struct libusb_interface_descriptor *altsetting;
-
-	/** The number of alternate settings that belong to this interface */
-	int num_altsetting;
-};
-
-/** \ingroup desc
- * A structure representing the standard USB configuration descriptor. This
- * descriptor is documented in section 9.6.3 of the USB 2.0 specification.
- * All multiple-byte fields are represented in host-endian format.
- */
-struct libusb_config_descriptor {
-	/** Size of this descriptor (in bytes) */
-	uint8_t  bLength;
-
-	/** Descriptor type. Will have value
-	 * \ref libusb_descriptor_type::LIBUSB_DT_CONFIG LIBUSB_DT_CONFIG
-	 * in this context. */
-	uint8_t  bDescriptorType;
-
-	/** Total length of data returned for this configuration */
-	uint16_t wTotalLength;
-
-	/** Number of interfaces supported by this configuration */
-	uint8_t  bNumInterfaces;
-
-	/** Identifier value for this configuration */
-	uint8_t  bConfigurationValue;
-
-	/** Index of string descriptor describing this configuration */
-	uint8_t  iConfiguration;
-
-	/** Configuration characteristics */
-	uint8_t  bmAttributes;
-
-	/** Maximum power consumption of the USB device from this bus in this
-	 * configuration when the device is fully opreation. Expressed in units
-	 * of 2 mA. */
-	uint8_t  MaxPower;
-
-	/** Array of interfaces supported by this configuration. The length of
-	 * this array is determined by the bNumInterfaces field. */
-	const struct libusb_interface *interface;
-
-	/** Extra descriptors. If libusb encounters unknown configuration
-	 * descriptors, it will store them here, should you wish to parse them. */
-	const unsigned char *extra;
-
-	/** Length of the extra descriptors, in bytes. */
-	int extra_length;
-};
-
-/** \ingroup asyncio
- * Setup packet for control transfers. */
-struct libusb_control_setup {
-	/** Request type. Bits 0:4 determine recipient, see
-	 * \ref libusb_request_recipient. Bits 5:6 determine type, see
-	 * \ref libusb_request_type. Bit 7 determines data transfer direction, see
-	 * \ref libusb_endpoint_direction.
-	 */
-	uint8_t  bmRequestType;
-
-	/** Request. If the type bits of bmRequestType are equal to
-	 * \ref libusb_request_type::LIBUSB_REQUEST_TYPE_STANDARD
-	 * "LIBUSB_REQUEST_TYPE_STANDARD" then this field refers to
-	 * \ref libusb_standard_request. For other cases, use of this field is
-	 * application-specific. */
-	uint8_t  bRequest;
-
-	/** Value. Varies according to request */
-	uint16_t wValue;
-
-	/** Index. Varies according to request, typically used to pass an index
-	 * or offset */
-	uint16_t wIndex;
-
-	/** Number of bytes to transfer */
-	uint16_t wLength;
-};
-
-#define LIBUSB_CONTROL_SETUP_SIZE (sizeof(struct libusb_control_setup))
-
-/* libusb */
-
-struct libusb_context;
-struct libusb_device;
-struct libusb_device_handle;
-
-/** \ingroup lib
- * Structure representing a libusb session. The concept of individual libusb
- * sessions allows for your program to use two libraries (or dynamically
- * load two modules) which both independently use libusb. This will prevent
- * interference between the individual libusb users - for example
- * libusb_set_debug() will not affect the other user of the library, and
- * libusb_exit() will not destroy resources that the other user is still
- * using.
- *
- * Sessions are created by libusb_init() and destroyed through libusb_exit().
- * If your application is guaranteed to only ever include a single libusb
- * user (i.e. you), you do not have to worry about contexts: pass NULL in
- * every function call where a context is required. The default context
- * will be used.
- *
- * For more information, see \ref contexts.
- */
-typedef struct libusb_context libusb_context;
-
-/** \ingroup dev
- * Structure representing a USB device detected on the system. This is an
- * opaque type for which you are only ever provided with a pointer, usually
- * originating from libusb_get_device_list().
- *
- * Certain operations can be performed on a device, but in order to do any
- * I/O you will have to first obtain a device handle using libusb_open().
- *
- * Devices are reference counted with libusb_device_ref() and
- * libusb_device_unref(), and are freed when the reference count reaches 0.
- * New devices presented by libusb_get_device_list() have a reference count of
- * 1, and libusb_free_device_list() can optionally decrease the reference count
- * on all devices in the list. libusb_open() adds another reference which is
- * later destroyed by libusb_close().
- */
-typedef struct libusb_device libusb_device;
-
-
-/** \ingroup dev
- * Structure representing a handle on a USB device. This is an opaque type for
- * which you are only ever provided with a pointer, usually originating from
- * libusb_open().
- *
- * A device handle is used to perform I/O and other operations. When finished
- * with a device handle, you should call libusb_close().
- */
-typedef struct libusb_device_handle libusb_device_handle;
-
-/** \ingroup dev
- * Speed codes. Indicates the speed at which the device is operating.
- */
-enum libusb_speed {
-    /** The OS doesn't report or know the device speed. */
-    LIBUSB_SPEED_UNKNOWN = 0,
-
-    /** The device is operating at low speed (1.5MBit/s). */
-    LIBUSB_SPEED_LOW = 1,
-
-    /** The device is operating at full speed (12MBit/s). */
-    LIBUSB_SPEED_FULL = 2,
-
-    /** The device is operating at high speed (480MBit/s). */
-    LIBUSB_SPEED_HIGH = 3,
-
-    /** The device is operating at super speed (5000MBit/s). */
-    LIBUSB_SPEED_SUPER = 4,
-};
-
-/** \ingroup misc
- * Error codes. Most libusb functions return 0 on success or one of these
- * codes on failure.
- * You can call \ref libusb_error_name() to retrieve a string representation
- * of an error code.
- */
-enum libusb_error {
-	/** Success (no error) */
-	LIBUSB_SUCCESS = 0,
-
-	/** Input/output error */
-	LIBUSB_ERROR_IO = -1,
-
-	/** Invalid parameter */
-	LIBUSB_ERROR_INVALID_PARAM = -2,
-
-	/** Access denied (insufficient permissions) */
-	LIBUSB_ERROR_ACCESS = -3,
-
-	/** No such device (it may have been disconnected) */
-	LIBUSB_ERROR_NO_DEVICE = -4,
-
-	/** Entity not found */
-	LIBUSB_ERROR_NOT_FOUND = -5,
-
-	/** Resource busy */
-	LIBUSB_ERROR_BUSY = -6,
-
-	/** Operation timed out */
-	LIBUSB_ERROR_TIMEOUT = -7,
-
-	/** Overflow */
-	LIBUSB_ERROR_OVERFLOW = -8,
-
-	/** Pipe error */
-	LIBUSB_ERROR_PIPE = -9,
-
-	/** System call interrupted (perhaps due to signal) */
-	LIBUSB_ERROR_INTERRUPTED = -10,
-
-	/** Insufficient memory */
-	LIBUSB_ERROR_NO_MEM = -11,
-
-	/** Operation not supported or unimplemented on this platform */
-	LIBUSB_ERROR_NOT_SUPPORTED = -12,
-
-	/* NB! Remember to update libusb_error_name()
-	   when adding new error codes here. */
-
-	/** Other error */
-	LIBUSB_ERROR_OTHER = -99
-};
-
-/** \ingroup asyncio
- * Transfer status codes */
-enum libusb_transfer_status {
-	/** Transfer completed without error. Note that this does not indicate
-	 * that the entire amount of requested data was transferred. */
-	LIBUSB_TRANSFER_COMPLETED,
-
-	/** Transfer failed */
-	LIBUSB_TRANSFER_ERROR,
-
-	/** Transfer timed out */
-	LIBUSB_TRANSFER_TIMED_OUT,
-
-	/** Transfer was cancelled */
-	LIBUSB_TRANSFER_CANCELLED,
-
-	/** For bulk/interrupt endpoints: halt condition detected (endpoint
-	 * stalled). For control endpoints: control request not supported. */
-	LIBUSB_TRANSFER_STALL,
-
-	/** Device was disconnected */
-	LIBUSB_TRANSFER_NO_DEVICE,
-
-	/** Device sent more data than requested */
-	LIBUSB_TRANSFER_OVERFLOW
-};
-
-/** \ingroup asyncio
- * libusb_transfer.flags values */
-enum libusb_transfer_flags {
-	/** Report short frames as errors */
-	LIBUSB_TRANSFER_SHORT_NOT_OK = 1<<0,
-
-	/** Automatically free() transfer buffer during libusb_free_transfer() */
-	LIBUSB_TRANSFER_FREE_BUFFER = 1<<1,
-
-	/** Automatically call libusb_free_transfer() after callback returns.
-	 * If this flag is set, it is illegal to call libusb_free_transfer()
-	 * from your transfer callback, as this will result in a double-free
-	 * when this flag is acted upon. */
-	LIBUSB_TRANSFER_FREE_TRANSFER = 1<<2
-};
-
-/** \ingroup asyncio
- * Isochronous packet descriptor. */
-struct libusb_iso_packet_descriptor {
-	/** Length of data to request in this packet */
-	unsigned int length;
-
-	/** Amount of data that was actually transferred */
-	unsigned int actual_length;
-
-	/** Status code for this packet */
-	enum libusb_transfer_status status;
-};
-
-struct libusb_transfer;
-
-/** \ingroup asyncio
- * Asynchronous transfer callback function type. When submitting asynchronous
- * transfers, you pass a pointer to a callback function of this type via the
- * \ref libusb_transfer::callback "callback" member of the libusb_transfer
- * structure. libusb will call this function later, when the transfer has
- * completed or failed. See \ref asyncio for more information.
- * \param transfer The libusb_transfer struct the callback function is being
- * notified about.
- */
-typedef void (LIBUSB_CALL *libusb_transfer_cb_fn)(struct libusb_transfer *transfer);
-
-/** \ingroup asyncio
- * The generic USB transfer structure. The user populates this structure and
- * then submits it in order to request a transfer. After the transfer has
- * completed, the library populates the transfer with the results and passes
- * it back to the user.
- */
-struct libusb_transfer {
-	/** Handle of the device that this transfer will be submitted to */
-	libusb_device_handle *dev_handle;
-
-	/** A bitwise OR combination of \ref libusb_transfer_flags. */
-	uint8_t flags;
-
-	/** Address of the endpoint where this transfer will be sent. */
-	unsigned char endpoint;
-
-	/** Type of the endpoint from \ref libusb_transfer_type */
-	unsigned char type;
-
-	/** Timeout for this transfer in millseconds. A value of 0 indicates no
-	 * timeout. */
-	unsigned int timeout;
-
-	/** The status of the transfer. Read-only, and only for use within
-	 * transfer callback function.
-	 *
-	 * If this is an isochronous transfer, this field may read COMPLETED even
-	 * if there were errors in the frames. Use the
-	 * \ref libusb_iso_packet_descriptor::status "status" field in each packet
-	 * to determine if errors occurred. */
-	enum libusb_transfer_status status;
-
-	/** Length of the data buffer */
-	int length;
-
-	/** Actual length of data that was transferred. Read-only, and only for
-	 * use within transfer callback function. Not valid for isochronous
-	 * endpoint transfers. */
-	int actual_length;
-
-	/** Callback function. This will be invoked when the transfer completes,
-	 * fails, or is cancelled. */
-	libusb_transfer_cb_fn callback;
-
-	/** User context data to pass to the callback function. */
-	void *user_data;
-
-	/** Data buffer */
-	unsigned char *buffer;
-
-	/** Number of isochronous packets. Only used for I/O with isochronous
-	 * endpoints. */
-	int num_iso_packets;
-
-	/** Isochronous packet descriptors, for isochronous transfers only. */
-	struct libusb_iso_packet_descriptor iso_packet_desc
-#if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L)
-	[] /* valid C99 code */
-#else
-	[0] /* non-standard, but usually working code */
-#endif
-	;
-};
-
-/** \ingroup misc
- * Capabilities supported by this instance of libusb. Test if the running
- * library supports a given capability by calling
- * \ref libusb_has_capability().
- */
-enum libusb_capability {
-	/** The libusb_get_device_speed() API is available. */
-	LIBUSB_CAN_GET_DEVICE_SPEED = 0,
-};
-
-int LIBUSB_CALL libusb_init(libusb_context **ctx);
-void LIBUSB_CALL libusb_exit(libusb_context *ctx);
-void LIBUSB_CALL libusb_set_debug(libusb_context *ctx, int level);
-int LIBUSB_CALL libusb_has_capability(uint32_t capability);
-const char * LIBUSB_CALL libusb_error_name(int errcode);
-
-ssize_t LIBUSB_CALL libusb_get_device_list(libusb_context *ctx,
-	libusb_device ***list);
-void LIBUSB_CALL libusb_free_device_list(libusb_device **list,
-	int unref_devices);
-libusb_device * LIBUSB_CALL libusb_ref_device(libusb_device *dev);
-void LIBUSB_CALL libusb_unref_device(libusb_device *dev);
-
-int LIBUSB_CALL libusb_get_configuration(libusb_device_handle *dev,
-	int *config);
-int LIBUSB_CALL libusb_get_device_descriptor(libusb_device *dev,
-	struct libusb_device_descriptor *desc);
-int LIBUSB_CALL libusb_get_active_config_descriptor(libusb_device *dev,
-	struct libusb_config_descriptor **config);
-int LIBUSB_CALL libusb_get_config_descriptor(libusb_device *dev,
-	uint8_t config_index, struct libusb_config_descriptor **config);
-int LIBUSB_CALL libusb_get_config_descriptor_by_value(libusb_device *dev,
-	uint8_t bConfigurationValue, struct libusb_config_descriptor **config);
-void LIBUSB_CALL libusb_free_config_descriptor(
-	struct libusb_config_descriptor *config);
-uint8_t LIBUSB_CALL libusb_get_bus_number(libusb_device *dev);
-uint8_t LIBUSB_CALL libusb_get_device_address(libusb_device *dev);
-int LIBUSB_CALL libusb_get_device_speed(libusb_device *dev);
-int LIBUSB_CALL libusb_get_max_packet_size(libusb_device *dev,
-	unsigned char endpoint);
-int LIBUSB_CALL libusb_get_max_iso_packet_size(libusb_device *dev,
-	unsigned char endpoint);
-
-int LIBUSB_CALL libusb_open(libusb_device *dev, libusb_device_handle **handle);
-void LIBUSB_CALL libusb_close(libusb_device_handle *dev_handle);
-libusb_device * LIBUSB_CALL libusb_get_device(libusb_device_handle *dev_handle);
-
-int LIBUSB_CALL libusb_set_configuration(libusb_device_handle *dev,
-	int configuration);
-int LIBUSB_CALL libusb_claim_interface(libusb_device_handle *dev,
-	int interface_number);
-int LIBUSB_CALL libusb_release_interface(libusb_device_handle *dev,
-	int interface_number);
-
-libusb_device_handle * LIBUSB_CALL libusb_open_device_with_vid_pid(
-	libusb_context *ctx, uint16_t vendor_id, uint16_t product_id);
-
-int LIBUSB_CALL libusb_set_interface_alt_setting(libusb_device_handle *dev,
-	int interface_number, int alternate_setting);
-int LIBUSB_CALL libusb_clear_halt(libusb_device_handle *dev,
-	unsigned char endpoint);
-int LIBUSB_CALL libusb_reset_device(libusb_device_handle *dev);
-
-int LIBUSB_CALL libusb_kernel_driver_active(libusb_device_handle *dev,
-	int interface_number);
-int LIBUSB_CALL libusb_detach_kernel_driver(libusb_device_handle *dev,
-	int interface_number);
-int LIBUSB_CALL libusb_attach_kernel_driver(libusb_device_handle *dev,
-	int interface_number);
-
-/* async I/O */
-
-/** \ingroup asyncio
- * Get the data section of a control transfer. This convenience function is here
- * to remind you that the data does not start until 8 bytes into the actual
- * buffer, as the setup packet comes first.
- *
- * Calling this function only makes sense from a transfer callback function,
- * or situations where you have already allocated a suitably sized buffer at
- * transfer->buffer.
- *
- * \param transfer a transfer
- * \returns pointer to the first byte of the data section
- */
-static inline unsigned char *libusb_control_transfer_get_data(
-	struct libusb_transfer *transfer)
-{
-	return transfer->buffer + LIBUSB_CONTROL_SETUP_SIZE;
-}
-
-/** \ingroup asyncio
- * Get the control setup packet of a control transfer. This convenience
- * function is here to remind you that the control setup occupies the first
- * 8 bytes of the transfer data buffer.
- *
- * Calling this function only makes sense from a transfer callback function,
- * or situations where you have already allocated a suitably sized buffer at
- * transfer->buffer.
- *
- * \param transfer a transfer
- * \returns a casted pointer to the start of the transfer data buffer
- */
-static inline struct libusb_control_setup *libusb_control_transfer_get_setup(
-	struct libusb_transfer *transfer)
-{
-	return (struct libusb_control_setup *) transfer->buffer;
-}
-
-/** \ingroup asyncio
- * Helper function to populate the setup packet (first 8 bytes of the data
- * buffer) for a control transfer. The wIndex, wValue and wLength values should
- * be given in host-endian byte order.
- *
- * \param buffer buffer to output the setup packet into
- * \param bmRequestType see the
- * \ref libusb_control_setup::bmRequestType "bmRequestType" field of
- * \ref libusb_control_setup
- * \param bRequest see the
- * \ref libusb_control_setup::bRequest "bRequest" field of
- * \ref libusb_control_setup
- * \param wValue see the
- * \ref libusb_control_setup::wValue "wValue" field of
- * \ref libusb_control_setup
- * \param wIndex see the
- * \ref libusb_control_setup::wIndex "wIndex" field of
- * \ref libusb_control_setup
- * \param wLength see the
- * \ref libusb_control_setup::wLength "wLength" field of
- * \ref libusb_control_setup
- */
-static inline void libusb_fill_control_setup(unsigned char *buffer,
-	uint8_t bmRequestType, uint8_t bRequest, uint16_t wValue, uint16_t wIndex,
-	uint16_t wLength)
-{
-	struct libusb_control_setup *setup = (struct libusb_control_setup *) buffer;
-	setup->bmRequestType = bmRequestType;
-	setup->bRequest = bRequest;
-	setup->wValue = libusb_cpu_to_le16(wValue);
-	setup->wIndex = libusb_cpu_to_le16(wIndex);
-	setup->wLength = libusb_cpu_to_le16(wLength);
-}
-
-struct libusb_transfer * LIBUSB_CALL libusb_alloc_transfer(int iso_packets);
-int LIBUSB_CALL libusb_submit_transfer(struct libusb_transfer *transfer);
-int LIBUSB_CALL libusb_cancel_transfer(struct libusb_transfer *transfer);
-void LIBUSB_CALL libusb_free_transfer(struct libusb_transfer *transfer);
-
-/** \ingroup asyncio
- * Helper function to populate the required \ref libusb_transfer fields
- * for a control transfer.
- *
- * If you pass a transfer buffer to this function, the first 8 bytes will
- * be interpreted as a control setup packet, and the wLength field will be
- * used to automatically populate the \ref libusb_transfer::length "length"
- * field of the transfer. Therefore the recommended approach is:
- * -# Allocate a suitably sized data buffer (including space for control setup)
- * -# Call libusb_fill_control_setup()
- * -# If this is a host-to-device transfer with a data stage, put the data
- *    in place after the setup packet
- * -# Call this function
- * -# Call libusb_submit_transfer()
- *
- * It is also legal to pass a NULL buffer to this function, in which case this
- * function will not attempt to populate the length field. Remember that you
- * must then populate the buffer and length fields later.
- *
- * \param transfer the transfer to populate
- * \param dev_handle handle of the device that will handle the transfer
- * \param buffer data buffer. If provided, this function will interpret the
- * first 8 bytes as a setup packet and infer the transfer length from that.
- * \param callback callback function to be invoked on transfer completion
- * \param user_data user data to pass to callback function
- * \param timeout timeout for the transfer in milliseconds
- */
-static inline void libusb_fill_control_transfer(
-	struct libusb_transfer *transfer, libusb_device_handle *dev_handle,
-	unsigned char *buffer, libusb_transfer_cb_fn callback, void *user_data,
-	unsigned int timeout)
-{
-	struct libusb_control_setup *setup = (struct libusb_control_setup *) buffer;
-	transfer->dev_handle = dev_handle;
-	transfer->endpoint = 0;
-	transfer->type = LIBUSB_TRANSFER_TYPE_CONTROL;
-	transfer->timeout = timeout;
-	transfer->buffer = buffer;
-	if (setup)
-		transfer->length = LIBUSB_CONTROL_SETUP_SIZE
-			+ libusb_le16_to_cpu(setup->wLength);
-	transfer->user_data = user_data;
-	transfer->callback = callback;
-}
-
-/** \ingroup asyncio
- * Helper function to populate the required \ref libusb_transfer fields
- * for a bulk transfer.
- *
- * \param transfer the transfer to populate
- * \param dev_handle handle of the device that will handle the transfer
- * \param endpoint address of the endpoint where this transfer will be sent
- * \param buffer data buffer
- * \param length length of data buffer
- * \param callback callback function to be invoked on transfer completion
- * \param user_data user data to pass to callback function
- * \param timeout timeout for the transfer in milliseconds
- */
-static inline void libusb_fill_bulk_transfer(struct libusb_transfer *transfer,
-	libusb_device_handle *dev_handle, unsigned char endpoint,
-	unsigned char *buffer, int length, libusb_transfer_cb_fn callback,
-	void *user_data, unsigned int timeout)
-{
-	transfer->dev_handle = dev_handle;
-	transfer->endpoint = endpoint;
-	transfer->type = LIBUSB_TRANSFER_TYPE_BULK;
-	transfer->timeout = timeout;
-	transfer->buffer = buffer;
-	transfer->length = length;
-	transfer->user_data = user_data;
-	transfer->callback = callback;
-}
-
-/** \ingroup asyncio
- * Helper function to populate the required \ref libusb_transfer fields
- * for an interrupt transfer.
- *
- * \param transfer the transfer to populate
- * \param dev_handle handle of the device that will handle the transfer
- * \param endpoint address of the endpoint where this transfer will be sent
- * \param buffer data buffer
- * \param length length of data buffer
- * \param callback callback function to be invoked on transfer completion
- * \param user_data user data to pass to callback function
- * \param timeout timeout for the transfer in milliseconds
- */
-static inline void libusb_fill_interrupt_transfer(
-	struct libusb_transfer *transfer, libusb_device_handle *dev_handle,
-	unsigned char endpoint, unsigned char *buffer, int length,
-	libusb_transfer_cb_fn callback, void *user_data, unsigned int timeout)
-{
-	transfer->dev_handle = dev_handle;
-	transfer->endpoint = endpoint;
-	transfer->type = LIBUSB_TRANSFER_TYPE_INTERRUPT;
-	transfer->timeout = timeout;
-	transfer->buffer = buffer;
-	transfer->length = length;
-	transfer->user_data = user_data;
-	transfer->callback = callback;
-}
-
-/** \ingroup asyncio
- * Helper function to populate the required \ref libusb_transfer fields
- * for an isochronous transfer.
- *
- * \param transfer the transfer to populate
- * \param dev_handle handle of the device that will handle the transfer
- * \param endpoint address of the endpoint where this transfer will be sent
- * \param buffer data buffer
- * \param length length of data buffer
- * \param num_iso_packets the number of isochronous packets
- * \param callback callback function to be invoked on transfer completion
- * \param user_data user data to pass to callback function
- * \param timeout timeout for the transfer in milliseconds
- */
-static inline void libusb_fill_iso_transfer(struct libusb_transfer *transfer,
-	libusb_device_handle *dev_handle, unsigned char endpoint,
-	unsigned char *buffer, int length, int num_iso_packets,
-	libusb_transfer_cb_fn callback, void *user_data, unsigned int timeout)
-{
-	transfer->dev_handle = dev_handle;
-	transfer->endpoint = endpoint;
-	transfer->type = LIBUSB_TRANSFER_TYPE_ISOCHRONOUS;
-	transfer->timeout = timeout;
-	transfer->buffer = buffer;
-	transfer->length = length;
-	transfer->num_iso_packets = num_iso_packets;
-	transfer->user_data = user_data;
-	transfer->callback = callback;
-}
-
-/** \ingroup asyncio
- * Convenience function to set the length of all packets in an isochronous
- * transfer, based on the num_iso_packets field in the transfer structure.
- *
- * \param transfer a transfer
- * \param length the length to set in each isochronous packet descriptor
- * \see libusb_get_max_packet_size()
- */
-static inline void libusb_set_iso_packet_lengths(
-	struct libusb_transfer *transfer, unsigned int length)
-{
-	int i;
-	for (i = 0; i < transfer->num_iso_packets; i++)
-		transfer->iso_packet_desc[i].length = length;
-}
-
-/** \ingroup asyncio
- * Convenience function to locate the position of an isochronous packet
- * within the buffer of an isochronous transfer.
- *
- * This is a thorough function which loops through all preceding packets,
- * accumulating their lengths to find the position of the specified packet.
- * Typically you will assign equal lengths to each packet in the transfer,
- * and hence the above method is sub-optimal. You may wish to use
- * libusb_get_iso_packet_buffer_simple() instead.
- *
- * \param transfer a transfer
- * \param packet the packet to return the address of
- * \returns the base address of the packet buffer inside the transfer buffer,
- * or NULL if the packet does not exist.
- * \see libusb_get_iso_packet_buffer_simple()
- */
-static inline unsigned char *libusb_get_iso_packet_buffer(
-	struct libusb_transfer *transfer, unsigned int packet)
-{
-	int i;
-	size_t offset = 0;
-	int _packet;
-
-	/* oops..slight bug in the API. packet is an unsigned int, but we use
-	 * signed integers almost everywhere else. range-check and convert to
-	 * signed to avoid compiler warnings. FIXME for libusb-2. */
-	if (packet > INT_MAX)
-		return NULL;
-	_packet = packet;
-
-	if (_packet >= transfer->num_iso_packets)
-		return NULL;
-
-	for (i = 0; i < _packet; i++)
-		offset += transfer->iso_packet_desc[i].length;
-
-	return transfer->buffer + offset;
-}
-
-/** \ingroup asyncio
- * Convenience function to locate the position of an isochronous packet
- * within the buffer of an isochronous transfer, for transfers where each
- * packet is of identical size.
- *
- * This function relies on the assumption that every packet within the transfer
- * is of identical size to the first packet. Calculating the location of
- * the packet buffer is then just a simple calculation:
- * <tt>buffer + (packet_size * packet)</tt>
- *
- * Do not use this function on transfers other than those that have identical
- * packet lengths for each packet.
- *
- * \param transfer a transfer
- * \param packet the packet to return the address of
- * \returns the base address of the packet buffer inside the transfer buffer,
- * or NULL if the packet does not exist.
- * \see libusb_get_iso_packet_buffer()
- */
-static inline unsigned char *libusb_get_iso_packet_buffer_simple(
-	struct libusb_transfer *transfer, unsigned int packet)
-{
-	int _packet;
-
-	/* oops..slight bug in the API. packet is an unsigned int, but we use
-	 * signed integers almost everywhere else. range-check and convert to
-	 * signed to avoid compiler warnings. FIXME for libusb-2. */
-	if (packet > INT_MAX)
-		return NULL;
-	_packet = packet;
-
-	if (_packet >= transfer->num_iso_packets)
-		return NULL;
-
-	return transfer->buffer + (transfer->iso_packet_desc[0].length * _packet);
-}
-
-/* sync I/O */
-
-int LIBUSB_CALL libusb_control_transfer(libusb_device_handle *dev_handle,
-	uint8_t request_type, uint8_t bRequest, uint16_t wValue, uint16_t wIndex,
-	unsigned char *data, uint16_t wLength, unsigned int timeout);
-
-int LIBUSB_CALL libusb_bulk_transfer(libusb_device_handle *dev_handle,
-	unsigned char endpoint, unsigned char *data, int length,
-	int *actual_length, unsigned int timeout);
-
-int LIBUSB_CALL libusb_interrupt_transfer(libusb_device_handle *dev_handle,
-	unsigned char endpoint, unsigned char *data, int length,
-	int *actual_length, unsigned int timeout);
-
-/** \ingroup desc
- * Retrieve a descriptor from the default control pipe.
- * This is a convenience function which formulates the appropriate control
- * message to retrieve the descriptor.
- *
- * \param dev a device handle
- * \param desc_type the descriptor type, see \ref libusb_descriptor_type
- * \param desc_index the index of the descriptor to retrieve
- * \param data output buffer for descriptor
- * \param length size of data buffer
- * \returns number of bytes returned in data, or LIBUSB_ERROR code on failure
- */
-static inline int libusb_get_descriptor(libusb_device_handle *dev,
-	uint8_t desc_type, uint8_t desc_index, unsigned char *data, int length)
-{
-	return libusb_control_transfer(dev, LIBUSB_ENDPOINT_IN,
-		LIBUSB_REQUEST_GET_DESCRIPTOR, (desc_type << 8) | desc_index, 0, data,
-		(uint16_t) length, 1000);
-}
-
-/** \ingroup desc
- * Retrieve a descriptor from a device.
- * This is a convenience function which formulates the appropriate control
- * message to retrieve the descriptor. The string returned is Unicode, as
- * detailed in the USB specifications.
- *
- * \param dev a device handle
- * \param desc_index the index of the descriptor to retrieve
- * \param langid the language ID for the string descriptor
- * \param data output buffer for descriptor
- * \param length size of data buffer
- * \returns number of bytes returned in data, or LIBUSB_ERROR code on failure
- * \see libusb_get_string_descriptor_ascii()
- */
-static inline int libusb_get_string_descriptor(libusb_device_handle *dev,
-	uint8_t desc_index, uint16_t langid, unsigned char *data, int length)
-{
-	return libusb_control_transfer(dev, LIBUSB_ENDPOINT_IN,
-		LIBUSB_REQUEST_GET_DESCRIPTOR, (LIBUSB_DT_STRING << 8) | desc_index,
-		langid, data, (uint16_t) length, 1000);
-}
-
-int LIBUSB_CALL libusb_get_string_descriptor_ascii(libusb_device_handle *dev,
-	uint8_t desc_index, unsigned char *data, int length);
-
-/* polling and timeouts */
-
-int LIBUSB_CALL libusb_try_lock_events(libusb_context *ctx);
-void LIBUSB_CALL libusb_lock_events(libusb_context *ctx);
-void LIBUSB_CALL libusb_unlock_events(libusb_context *ctx);
-int LIBUSB_CALL libusb_event_handling_ok(libusb_context *ctx);
-int LIBUSB_CALL libusb_event_handler_active(libusb_context *ctx);
-void LIBUSB_CALL libusb_lock_event_waiters(libusb_context *ctx);
-void LIBUSB_CALL libusb_unlock_event_waiters(libusb_context *ctx);
-int LIBUSB_CALL libusb_wait_for_event(libusb_context *ctx, struct timeval *tv);
-
-int LIBUSB_CALL libusb_handle_events_timeout(libusb_context *ctx,
-	struct timeval *tv);
-int LIBUSB_CALL libusb_handle_events_timeout_completed(libusb_context *ctx,
-	struct timeval *tv, int *completed);
-int LIBUSB_CALL libusb_handle_events(libusb_context *ctx);
-int LIBUSB_CALL libusb_handle_events_completed(libusb_context *ctx, int *completed);
-int LIBUSB_CALL libusb_handle_events_locked(libusb_context *ctx,
-	struct timeval *tv);
-int LIBUSB_CALL libusb_pollfds_handle_timeouts(libusb_context *ctx);
-int LIBUSB_CALL libusb_get_next_timeout(libusb_context *ctx,
-	struct timeval *tv);
-
-/** \ingroup poll
- * File descriptor for polling
- */
-struct libusb_pollfd {
-	/** Numeric file descriptor */
-	int fd;
-
-	/** Event flags to poll for from <poll.h>. POLLIN indicates that you
-	 * should monitor this file descriptor for becoming ready to read from,
-	 * and POLLOUT indicates that you should monitor this file descriptor for
-	 * nonblocking write readiness. */
-	short events;
-};
-
-/** \ingroup poll
- * Callback function, invoked when a new file descriptor should be added
- * to the set of file descriptors monitored for events.
- * \param fd the new file descriptor
- * \param events events to monitor for, see \ref libusb_pollfd for a
- * description
- * \param user_data User data pointer specified in
- * libusb_set_pollfd_notifiers() call
- * \see libusb_set_pollfd_notifiers()
- */
-typedef void (LIBUSB_CALL *libusb_pollfd_added_cb)(int fd, short events,
-	void *user_data);
-
-/** \ingroup poll
- * Callback function, invoked when a file descriptor should be removed from
- * the set of file descriptors being monitored for events. After returning
- * from this callback, do not use that file descriptor again.
- * \param fd the file descriptor to stop monitoring
- * \param user_data User data pointer specified in
- * libusb_set_pollfd_notifiers() call
- * \see libusb_set_pollfd_notifiers()
- */
-typedef void (LIBUSB_CALL *libusb_pollfd_removed_cb)(int fd, void *user_data);
-
-const struct libusb_pollfd ** LIBUSB_CALL libusb_get_pollfds(
-	libusb_context *ctx);
-void LIBUSB_CALL libusb_set_pollfd_notifiers(libusb_context *ctx,
-	libusb_pollfd_added_cb added_cb, libusb_pollfd_removed_cb removed_cb,
-	void *user_data);
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif
diff --git a/third_party/libusb/libusb/libusbi.h b/third_party/libusb/libusb/libusbi.h
deleted file mode 100644
index fe9b7af..0000000
--- a/third_party/libusb/libusb/libusbi.h
+++ /dev/null
@@ -1,889 +0,0 @@
-/*
- * Internal header for libusb
- * Copyright (C) 2007-2009 Daniel Drake <dsd@gentoo.org>
- * Copyright (c) 2001 Johannes Erdfelt <johannes@erdfelt.com>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#ifndef LIBUSBI_H
-#define LIBUSBI_H
-
-#include <config.h>
-
-#include <stddef.h>
-#include <stdint.h>
-#include <time.h>
-#ifdef HAVE_POLL_H
-#include <poll.h>
-#endif
-
-#include <libusb.h>
-
-/* Inside the libusb code, mark all public functions as follows:
- *   return_type API_EXPORTED function_name(params) { ... }
- * But if the function returns a pointer, mark it as follows:
- *   DEFAULT_VISIBILITY return_type * LIBUSB_CALL function_name(params) { ... }
- * In the libusb public header, mark all declarations as:
- *   return_type LIBUSB_CALL function_name(params);
- */
-#define API_EXPORTED LIBUSB_CALL DEFAULT_VISIBILITY
-
-#define DEVICE_DESC_LENGTH		18
-
-#define USB_MAXENDPOINTS	32
-#define USB_MAXINTERFACES	32
-#define USB_MAXCONFIG		8
-
-struct list_head {
-	struct list_head *prev, *next;
-};
-
-/* Get an entry from the list
- * 	ptr - the address of this list_head element in "type"
- * 	type - the data type that contains "member"
- * 	member - the list_head element in "type"
- */
-#define list_entry(ptr, type, member) \
-	((type *)((uintptr_t)(ptr) - (uintptr_t)(&((type *)0L)->member)))
-
-/* Get each entry from a list
- *	pos - A structure pointer has a "member" element
- *	head - list head
- *	member - the list_head element in "pos"
- *	type - the type of the first parameter
- */
-#define list_for_each_entry(pos, head, member, type)			\
-	for (pos = list_entry((head)->next, type, member);			\
-		 &pos->member != (head);								\
-		 pos = list_entry(pos->member.next, type, member))
-
-#define list_for_each_entry_safe(pos, n, head, member, type)	\
-	for (pos = list_entry((head)->next, type, member),			\
-		 n = list_entry(pos->member.next, type, member);		\
-		 &pos->member != (head);								\
-		 pos = n, n = list_entry(n->member.next, type, member))
-
-#define list_empty(entry) ((entry)->next == (entry))
-
-static inline void list_init(struct list_head *entry)
-{
-	entry->prev = entry->next = entry;
-}
-
-static inline void list_add(struct list_head *entry, struct list_head *head)
-{
-	entry->next = head->next;
-	entry->prev = head;
-
-	head->next->prev = entry;
-	head->next = entry;
-}
-
-static inline void list_add_tail(struct list_head *entry,
-	struct list_head *head)
-{
-	entry->next = head;
-	entry->prev = head->prev;
-
-	head->prev->next = entry;
-	head->prev = entry;
-}
-
-static inline void list_del(struct list_head *entry)
-{
-	entry->next->prev = entry->prev;
-	entry->prev->next = entry->next;
-}
-
-#define container_of(ptr, type, member) ({                      \
-        const typeof( ((type *)0)->member ) *mptr = (ptr);    \
-        (type *)( (char *)mptr - offsetof(type,member) );})
-
-#define MIN(a, b)	((a) < (b) ? (a) : (b))
-#define MAX(a, b)	((a) > (b) ? (a) : (b))
-
-#define TIMESPEC_IS_SET(ts) ((ts)->tv_sec != 0 || (ts)->tv_nsec != 0)
-
-enum usbi_log_level {
-	LOG_LEVEL_DEBUG,
-	LOG_LEVEL_INFO,
-	LOG_LEVEL_WARNING,
-	LOG_LEVEL_ERROR,
-};
-
-void usbi_log(struct libusb_context *ctx, enum usbi_log_level level,
-	const char *function, const char *format, ...);
-
-#if !defined(_MSC_VER) || _MSC_VER > 1200
-
-#ifdef ENABLE_LOGGING
-#define _usbi_log(ctx, level, ...) usbi_log(ctx, level, __FUNCTION__, __VA_ARGS__)
-#else
-#define _usbi_log(ctx, level, ...) do { (void)(ctx); } while(0)
-#endif
-
-#ifdef ENABLE_DEBUG_LOGGING
-#define usbi_dbg(...) _usbi_log(NULL, LOG_LEVEL_DEBUG, __VA_ARGS__)
-#else
-#define usbi_dbg(...) do {} while(0)
-#endif
-
-#define usbi_info(ctx, ...) _usbi_log(ctx, LOG_LEVEL_INFO, __VA_ARGS__)
-#define usbi_warn(ctx, ...) _usbi_log(ctx, LOG_LEVEL_WARNING, __VA_ARGS__)
-#define usbi_err(ctx, ...) _usbi_log(ctx, LOG_LEVEL_ERROR, __VA_ARGS__)
-
-#else /* !defined(_MSC_VER) || _MSC_VER > 1200 */
-
-void usbi_log_v(struct libusb_context *ctx, enum usbi_log_level level,
-	const char *function, const char *format, va_list args);
-
-#ifdef ENABLE_LOGGING
-#define LOG_BODY(ctxt, level) \
-{                             \
-	va_list args;             \
-	va_start (args, format);  \
-	usbi_log_v(ctxt, level, "", format, args); \
-	va_end(args);             \
-}
-#else
-#define LOG_BODY(ctxt, level) do { (void)(ctxt); } while(0)
-#endif
-
-static inline void usbi_info(struct libusb_context *ctx, const char *format,
-	...)
-	LOG_BODY(ctx,LOG_LEVEL_INFO)
-static inline void usbi_warn(struct libusb_context *ctx, const char *format,
-	...)
-	LOG_BODY(ctx,LOG_LEVEL_WARNING)
-static inline void usbi_err( struct libusb_context *ctx, const char *format,
-	...)
-	LOG_BODY(ctx,LOG_LEVEL_ERROR)
-
-static inline void usbi_dbg(const char *format, ...)
-#ifdef ENABLE_DEBUG_LOGGING
-	LOG_BODY(NULL,LOG_LEVEL_DEBUG)
-#else
-{ }
-#endif
-
-#endif /* !defined(_MSC_VER) || _MSC_VER > 1200 */
-
-#define USBI_GET_CONTEXT(ctx) if (!(ctx)) (ctx) = usbi_default_context
-#define DEVICE_CTX(dev) ((dev)->ctx)
-#define HANDLE_CTX(handle) (DEVICE_CTX((handle)->dev))
-#define TRANSFER_CTX(transfer) (HANDLE_CTX((transfer)->dev_handle))
-#define ITRANSFER_CTX(transfer) \
-	(TRANSFER_CTX(USBI_TRANSFER_TO_LIBUSB_TRANSFER(transfer)))
-
-/* Internal abstractions for thread synchronization and poll */
-#if defined(THREADS_POSIX)
-#include <os/threads_posix.h>
-#elif defined(OS_WINDOWS)
-#include <os/threads_windows.h>
-#endif
-
-#if defined(OS_LINUX) || defined(OS_DARWIN)
-#include <unistd.h>
-#include <os/poll_posix.h>
-#elif defined(OS_WINDOWS)
-#include <os/poll_windows.h>
-#endif
-
-extern struct libusb_context *usbi_default_context;
-
-struct libusb_context {
-	int debug;
-	int debug_fixed;
-
-	/* internal control pipe, used for interrupting event handling when
-	 * something needs to modify poll fds. */
-	int ctrl_pipe[2];
-
-	struct list_head usb_devs;
-	usbi_mutex_t usb_devs_lock;
-
-	/* A list of open handles. Backends are free to traverse this if required.
-	 */
-	struct list_head open_devs;
-	usbi_mutex_t open_devs_lock;
-
-	/* this is a list of in-flight transfer handles, sorted by timeout
-	 * expiration. URBs to timeout the soonest are placed at the beginning of
-	 * the list, URBs that will time out later are placed after, and urbs with
-	 * infinite timeout are always placed at the very end. */
-	struct list_head flying_transfers;
-	usbi_mutex_t flying_transfers_lock;
-
-	/* list of poll fds */
-	struct list_head pollfds;
-	usbi_mutex_t pollfds_lock;
-
-	/* a counter that is set when we want to interrupt event handling, in order
-	 * to modify the poll fd set. and a lock to protect it. */
-	unsigned int pollfd_modify;
-	usbi_mutex_t pollfd_modify_lock;
-
-	/* user callbacks for pollfd changes */
-	libusb_pollfd_added_cb fd_added_cb;
-	libusb_pollfd_removed_cb fd_removed_cb;
-	void *fd_cb_user_data;
-
-	/* ensures that only one thread is handling events at any one time */
-	usbi_mutex_t events_lock;
-
-	/* used to see if there is an active thread doing event handling */
-	int event_handler_active;
-
-	/* used to wait for event completion in threads other than the one that is
-	 * event handling */
-	usbi_mutex_t event_waiters_lock;
-	usbi_cond_t event_waiters_cond;
-
-#ifdef USBI_TIMERFD_AVAILABLE
-	/* used for timeout handling, if supported by OS.
-	 * this timerfd is maintained to trigger on the next pending timeout */
-	int timerfd;
-#endif
-};
-
-#ifdef USBI_TIMERFD_AVAILABLE
-#define usbi_using_timerfd(ctx) ((ctx)->timerfd >= 0)
-#else
-#define usbi_using_timerfd(ctx) (0)
-#endif
-
-struct libusb_device {
-	/* lock protects refcnt, everything else is finalized at initialization
-	 * time */
-	usbi_mutex_t lock;
-	int refcnt;
-
-	struct libusb_context *ctx;
-
-	uint8_t bus_number;
-	uint8_t device_address;
-	uint8_t num_configurations;
-	enum libusb_speed speed;
-
-	struct list_head list;
-	unsigned long session_data;
-	unsigned char os_priv[0];
-};
-
-struct libusb_device_handle {
-	/* lock protects claimed_interfaces */
-	usbi_mutex_t lock;
-	unsigned long claimed_interfaces;
-
-	struct list_head list;
-	struct libusb_device *dev;
-	unsigned char os_priv[0];
-};
-
-enum {
-  USBI_CLOCK_MONOTONIC,
-  USBI_CLOCK_REALTIME
-};
-
-/* in-memory transfer layout:
- *
- * 1. struct usbi_transfer
- * 2. struct libusb_transfer (which includes iso packets) [variable size]
- * 3. os private data [variable size]
- *
- * from a libusb_transfer, you can get the usbi_transfer by rewinding the
- * appropriate number of bytes.
- * the usbi_transfer includes the number of allocated packets, so you can
- * determine the size of the transfer and hence the start and length of the
- * OS-private data.
- */
-
-struct usbi_transfer {
-	int num_iso_packets;
-	struct list_head list;
-	struct timeval timeout;
-	int transferred;
-	uint8_t flags;
-
-	/* this lock is held during libusb_submit_transfer() and
-	 * libusb_cancel_transfer() (allowing the OS backend to prevent duplicate
-	 * cancellation, submission-during-cancellation, etc). the OS backend
-	 * should also take this lock in the handle_events path, to prevent the user
-	 * cancelling the transfer from another thread while you are processing
-	 * its completion (presumably there would be races within your OS backend
-	 * if this were possible). */
-	usbi_mutex_t lock;
-};
-
-enum usbi_transfer_flags {
-	/* The transfer has timed out */
-	USBI_TRANSFER_TIMED_OUT = 1 << 0,
-
-	/* Set by backend submit_transfer() if the OS handles timeout */
-	USBI_TRANSFER_OS_HANDLES_TIMEOUT = 1 << 1,
-
-	/* Cancellation was requested via libusb_cancel_transfer() */
-	USBI_TRANSFER_CANCELLING = 1 << 2,
-
-	/* Operation on the transfer failed because the device disappeared */
-	USBI_TRANSFER_DEVICE_DISAPPEARED = 1 << 3,
-};
-
-#define USBI_TRANSFER_TO_LIBUSB_TRANSFER(transfer) \
-	((struct libusb_transfer *)(((unsigned char *)(transfer)) \
-		+ sizeof(struct usbi_transfer)))
-#define LIBUSB_TRANSFER_TO_USBI_TRANSFER(transfer) \
-	((struct usbi_transfer *)(((unsigned char *)(transfer)) \
-		- sizeof(struct usbi_transfer)))
-
-static inline void *usbi_transfer_get_os_priv(struct usbi_transfer *transfer)
-{
-	return ((unsigned char *)transfer) + sizeof(struct usbi_transfer)
-		+ sizeof(struct libusb_transfer)
-		+ (transfer->num_iso_packets
-			* sizeof(struct libusb_iso_packet_descriptor));
-}
-
-/* bus structures */
-
-/* All standard descriptors have these 2 fields in common */
-struct usb_descriptor_header {
-	uint8_t  bLength;
-	uint8_t  bDescriptorType;
-};
-
-/* shared data and functions */
-
-int usbi_io_init(struct libusb_context *ctx);
-void usbi_io_exit(struct libusb_context *ctx);
-
-struct libusb_device *usbi_alloc_device(struct libusb_context *ctx,
-	unsigned long session_id);
-struct libusb_device *usbi_get_device_by_session_id(struct libusb_context *ctx,
-	unsigned long session_id);
-int usbi_sanitize_device(struct libusb_device *dev);
-void usbi_handle_disconnect(struct libusb_device_handle *handle);
-
-int usbi_handle_transfer_completion(struct usbi_transfer *itransfer,
-	enum libusb_transfer_status status);
-int usbi_handle_transfer_cancellation(struct usbi_transfer *transfer);
-
-int usbi_parse_descriptor(unsigned char *source, const char *descriptor,
-	void *dest, int host_endian);
-int usbi_get_config_index_by_value(struct libusb_device *dev,
-	uint8_t bConfigurationValue, int *idx);
-
-/* polling */
-
-struct usbi_pollfd {
-	/* must come first */
-	struct libusb_pollfd pollfd;
-
-	struct list_head list;
-};
-
-int usbi_add_pollfd(struct libusb_context *ctx, int fd, short events);
-void usbi_remove_pollfd(struct libusb_context *ctx, int fd);
-void usbi_fd_notification(struct libusb_context *ctx);
-
-/* device discovery */
-
-/* we traverse usbfs without knowing how many devices we are going to find.
- * so we create this discovered_devs model which is similar to a linked-list
- * which grows when required. it can be freed once discovery has completed,
- * eliminating the need for a list node in the libusb_device structure
- * itself. */
-struct discovered_devs {
-	size_t len;
-	size_t capacity;
-	struct libusb_device *devices[0];
-};
-
-struct discovered_devs *discovered_devs_append(
-	struct discovered_devs *discdevs, struct libusb_device *dev);
-
-/* OS abstraction */
-
-/* This is the interface that OS backends need to implement.
- * All fields are mandatory, except ones explicitly noted as optional. */
-struct usbi_os_backend {
-	/* A human-readable name for your backend, e.g. "Linux usbfs" */
-	const char *name;
-
-	/* Perform initialization of your backend. You might use this function
-	 * to determine specific capabilities of the system, allocate required
-	 * data structures for later, etc.
-	 *
-	 * This function is called when a libusb user initializes the library
-	 * prior to use.
-	 *
-	 * Return 0 on success, or a LIBUSB_ERROR code on failure.
-	 */
-	int (*init)(struct libusb_context *ctx);
-
-	/* Deinitialization. Optional. This function should destroy anything
-	 * that was set up by init.
-	 *
-	 * This function is called when the user deinitializes the library.
-	 */
-	void (*exit)(void);
-
-	/* Enumerate all the USB devices on the system, returning them in a list
-	 * of discovered devices.
-	 *
-	 * Your implementation should enumerate all devices on the system,
-	 * regardless of whether they have been seen before or not.
-	 *
-	 * When you have found a device, compute a session ID for it. The session
-	 * ID should uniquely represent that particular device for that particular
-	 * connection session since boot (i.e. if you disconnect and reconnect a
-	 * device immediately after, it should be assigned a different session ID).
-	 * If your OS cannot provide a unique session ID as described above,
-	 * presenting a session ID of (bus_number << 8 | device_address) should
-	 * be sufficient. Bus numbers and device addresses wrap and get reused,
-	 * but that is an unlikely case.
-	 *
-	 * After computing a session ID for a device, call
-	 * usbi_get_device_by_session_id(). This function checks if libusb already
-	 * knows about the device, and if so, it provides you with a libusb_device
-	 * structure for it.
-	 *
-	 * If usbi_get_device_by_session_id() returns NULL, it is time to allocate
-	 * a new device structure for the device. Call usbi_alloc_device() to
-	 * obtain a new libusb_device structure with reference count 1. Populate
-	 * the bus_number and device_address attributes of the new device, and
-	 * perform any other internal backend initialization you need to do. At
-	 * this point, you should be ready to provide device descriptors and so
-	 * on through the get_*_descriptor functions. Finally, call
-	 * usbi_sanitize_device() to perform some final sanity checks on the
-	 * device. Assuming all of the above succeeded, we can now continue.
-	 * If any of the above failed, remember to unreference the device that
-	 * was returned by usbi_alloc_device().
-	 *
-	 * At this stage we have a populated libusb_device structure (either one
-	 * that was found earlier, or one that we have just allocated and
-	 * populated). This can now be added to the discovered devices list
-	 * using discovered_devs_append(). Note that discovered_devs_append()
-	 * may reallocate the list, returning a new location for it, and also
-	 * note that reallocation can fail. Your backend should handle these
-	 * error conditions appropriately.
-	 *
-	 * This function should not generate any bus I/O and should not block.
-	 * If I/O is required (e.g. reading the active configuration value), it is
-	 * OK to ignore these suggestions :)
-	 *
-	 * This function is executed when the user wishes to retrieve a list
-	 * of USB devices connected to the system.
-	 *
-	 * Return 0 on success, or a LIBUSB_ERROR code on failure.
-	 */
-	int (*get_device_list)(struct libusb_context *ctx,
-		struct discovered_devs **discdevs);
-
-	/* Open a device for I/O and other USB operations. The device handle
-	 * is preallocated for you, you can retrieve the device in question
-	 * through handle->dev.
-	 *
-	 * Your backend should allocate any internal resources required for I/O
-	 * and other operations so that those operations can happen (hopefully)
-	 * without hiccup. This is also a good place to inform libusb that it
-	 * should monitor certain file descriptors related to this device -
-	 * see the usbi_add_pollfd() function.
-	 *
-	 * This function should not generate any bus I/O and should not block.
-	 *
-	 * This function is called when the user attempts to obtain a device
-	 * handle for a device.
-	 *
-	 * Return:
-	 * - 0 on success
-	 * - LIBUSB_ERROR_ACCESS if the user has insufficient permissions
-	 * - LIBUSB_ERROR_NO_DEVICE if the device has been disconnected since
-	 *   discovery
-	 * - another LIBUSB_ERROR code on other failure
-	 *
-	 * Do not worry about freeing the handle on failed open, the upper layers
-	 * do this for you.
-	 */
-	int (*open)(struct libusb_device_handle *handle);
-
-	/* Close a device such that the handle cannot be used again. Your backend
-	 * should destroy any resources that were allocated in the open path.
-	 * This may also be a good place to call usbi_remove_pollfd() to inform
-	 * libusb of any file descriptors associated with this device that should
-	 * no longer be monitored.
-	 *
-	 * This function is called when the user closes a device handle.
-	 */
-	void (*close)(struct libusb_device_handle *handle);
-
-	/* Retrieve the device descriptor from a device.
-	 *
-	 * The descriptor should be retrieved from memory, NOT via bus I/O to the
-	 * device. This means that you may have to cache it in a private structure
-	 * during get_device_list enumeration. Alternatively, you may be able
-	 * to retrieve it from a kernel interface (some Linux setups can do this)
-	 * still without generating bus I/O.
-	 *
-	 * This function is expected to write DEVICE_DESC_LENGTH (18) bytes into
-	 * buffer, which is guaranteed to be big enough.
-	 *
-	 * This function is called when sanity-checking a device before adding
-	 * it to the list of discovered devices, and also when the user requests
-	 * to read the device descriptor.
-	 *
-	 * This function is expected to return the descriptor in bus-endian format
-	 * (LE). If it returns the multi-byte values in host-endian format,
-	 * set the host_endian output parameter to "1".
-	 *
-	 * Return 0 on success or a LIBUSB_ERROR code on failure.
-	 */
-	int (*get_device_descriptor)(struct libusb_device *device,
-		unsigned char *buffer, int *host_endian);
-
-	/* Get the ACTIVE configuration descriptor for a device.
-	 *
-	 * The descriptor should be retrieved from memory, NOT via bus I/O to the
-	 * device. This means that you may have to cache it in a private structure
-	 * during get_device_list enumeration. You may also have to keep track
-	 * of which configuration is active when the user changes it.
-	 *
-	 * This function is expected to write len bytes of data into buffer, which
-	 * is guaranteed to be big enough. If you can only do a partial write,
-	 * return an error code.
-	 *
-	 * This function is expected to return the descriptor in bus-endian format
-	 * (LE). If it returns the multi-byte values in host-endian format,
-	 * set the host_endian output parameter to "1".
-	 *
-	 * Return:
-	 * - 0 on success
-	 * - LIBUSB_ERROR_NOT_FOUND if the device is in unconfigured state
-	 * - another LIBUSB_ERROR code on other failure
-	 */
-	int (*get_active_config_descriptor)(struct libusb_device *device,
-		unsigned char *buffer, size_t len, int *host_endian);
-
-	/* Get a specific configuration descriptor for a device.
-	 *
-	 * The descriptor should be retrieved from memory, NOT via bus I/O to the
-	 * device. This means that you may have to cache it in a private structure
-	 * during get_device_list enumeration.
-	 *
-	 * The requested descriptor is expressed as a zero-based index (i.e. 0
-	 * indicates that we are requesting the first descriptor). The index does
-	 * not (necessarily) equal the bConfigurationValue of the configuration
-	 * being requested.
-	 *
-	 * This function is expected to write len bytes of data into buffer, which
-	 * is guaranteed to be big enough. If you can only do a partial write,
-	 * return an error code.
-	 *
-	 * This function is expected to return the descriptor in bus-endian format
-	 * (LE). If it returns the multi-byte values in host-endian format,
-	 * set the host_endian output parameter to "1".
-	 *
-	 * Return 0 on success or a LIBUSB_ERROR code on failure.
-	 */
-	int (*get_config_descriptor)(struct libusb_device *device,
-		uint8_t config_index, unsigned char *buffer, size_t len,
-		int *host_endian);
-
-	/* Get the bConfigurationValue for the active configuration for a device.
-	 * Optional. This should only be implemented if you can retrieve it from
-	 * cache (don't generate I/O).
-	 *
-	 * If you cannot retrieve this from cache, either do not implement this
-	 * function, or return LIBUSB_ERROR_NOT_SUPPORTED. This will cause
-	 * libusb to retrieve the information through a standard control transfer.
-	 *
-	 * This function must be non-blocking.
-	 * Return:
-	 * - 0 on success
-	 * - LIBUSB_ERROR_NO_DEVICE if the device has been disconnected since it
-	 *   was opened
-	 * - LIBUSB_ERROR_NOT_SUPPORTED if the value cannot be retrieved without
-	 *   blocking
-	 * - another LIBUSB_ERROR code on other failure.
-	 */
-	int (*get_configuration)(struct libusb_device_handle *handle, int *config);
-
-	/* Set the active configuration for a device.
-	 *
-	 * A configuration value of -1 should put the device in unconfigured state.
-	 *
-	 * This function can block.
-	 *
-	 * Return:
-	 * - 0 on success
-	 * - LIBUSB_ERROR_NOT_FOUND if the configuration does not exist
-	 * - LIBUSB_ERROR_BUSY if interfaces are currently claimed (and hence
-	 *   configuration cannot be changed)
-	 * - LIBUSB_ERROR_NO_DEVICE if the device has been disconnected since it
-	 *   was opened
-	 * - another LIBUSB_ERROR code on other failure.
-	 */
-	int (*set_configuration)(struct libusb_device_handle *handle, int config);
-
-	/* Claim an interface. When claimed, the application can then perform
-	 * I/O to an interface's endpoints.
-	 *
-	 * This function should not generate any bus I/O and should not block.
-	 * Interface claiming is a logical operation that simply ensures that
-	 * no other drivers/applications are using the interface, and after
-	 * claiming, no other drivers/applicatiosn can use the interface because
-	 * we now "own" it.
-	 *
-	 * Return:
-	 * - 0 on success
-	 * - LIBUSB_ERROR_NOT_FOUND if the interface does not exist
-	 * - LIBUSB_ERROR_BUSY if the interface is in use by another driver/app
-	 * - LIBUSB_ERROR_NO_DEVICE if the device has been disconnected since it
-	 *   was opened
-	 * - another LIBUSB_ERROR code on other failure
-	 */
-	int (*claim_interface)(struct libusb_device_handle *handle, int interface_number);
-
-	/* Release a previously claimed interface.
-	 *
-	 * This function should also generate a SET_INTERFACE control request,
-	 * resetting the alternate setting of that interface to 0. It's OK for
-	 * this function to block as a result.
-	 *
-	 * You will only ever be asked to release an interface which was
-	 * successfully claimed earlier.
-	 *
-	 * Return:
-	 * - 0 on success
-	 * - LIBUSB_ERROR_NO_DEVICE if the device has been disconnected since it
-	 *   was opened
-	 * - another LIBUSB_ERROR code on other failure
-	 */
-	int (*release_interface)(struct libusb_device_handle *handle, int interface_number);
-
-	/* Set the alternate setting for an interface.
-	 *
-	 * You will only ever be asked to set the alternate setting for an
-	 * interface which was successfully claimed earlier.
-	 *
-	 * It's OK for this function to block.
-	 *
-	 * Return:
-	 * - 0 on success
-	 * - LIBUSB_ERROR_NOT_FOUND if the alternate setting does not exist
-	 * - LIBUSB_ERROR_NO_DEVICE if the device has been disconnected since it
-	 *   was opened
-	 * - another LIBUSB_ERROR code on other failure
-	 */
-	int (*set_interface_altsetting)(struct libusb_device_handle *handle,
-		int interface_number, int altsetting);
-
-	/* Clear a halt/stall condition on an endpoint.
-	 *
-	 * It's OK for this function to block.
-	 *
-	 * Return:
-	 * - 0 on success
-	 * - LIBUSB_ERROR_NOT_FOUND if the endpoint does not exist
-	 * - LIBUSB_ERROR_NO_DEVICE if the device has been disconnected since it
-	 *   was opened
-	 * - another LIBUSB_ERROR code on other failure
-	 */
-	int (*clear_halt)(struct libusb_device_handle *handle,
-		unsigned char endpoint);
-
-	/* Perform a USB port reset to reinitialize a device.
-	 *
-	 * If possible, the handle should still be usable after the reset
-	 * completes, assuming that the device descriptors did not change during
-	 * reset and all previous interface state can be restored.
-	 *
-	 * If something changes, or you cannot easily locate/verify the resetted
-	 * device, return LIBUSB_ERROR_NOT_FOUND. This prompts the application
-	 * to close the old handle and re-enumerate the device.
-	 *
-	 * Return:
-	 * - 0 on success
-	 * - LIBUSB_ERROR_NOT_FOUND if re-enumeration is required, or if the device
-	 *   has been disconnected since it was opened
-	 * - another LIBUSB_ERROR code on other failure
-	 */
-	int (*reset_device)(struct libusb_device_handle *handle);
-
-	/* Determine if a kernel driver is active on an interface. Optional.
-	 *
-	 * The presence of a kernel driver on an interface indicates that any
-	 * calls to claim_interface would fail with the LIBUSB_ERROR_BUSY code.
-	 *
-	 * Return:
-	 * - 0 if no driver is active
-	 * - 1 if a driver is active
-	 * - LIBUSB_ERROR_NO_DEVICE if the device has been disconnected since it
-	 *   was opened
-	 * - another LIBUSB_ERROR code on other failure
-	 */
-	int (*kernel_driver_active)(struct libusb_device_handle *handle,
-		int interface_number);
-
-	/* Detach a kernel driver from an interface. Optional.
-	 *
-	 * After detaching a kernel driver, the interface should be available
-	 * for claim.
-	 *
-	 * Return:
-	 * - 0 on success
-	 * - LIBUSB_ERROR_NOT_FOUND if no kernel driver was active
-	 * - LIBUSB_ERROR_INVALID_PARAM if the interface does not exist
-	 * - LIBUSB_ERROR_NO_DEVICE if the device has been disconnected since it
-	 *   was opened
-	 * - another LIBUSB_ERROR code on other failure
-	 */
-	int (*detach_kernel_driver)(struct libusb_device_handle *handle,
-		int interface_number);
-
-	/* Attach a kernel driver to an interface. Optional.
-	 *
-	 * Reattach a kernel driver to the device.
-	 *
-	 * Return:
-	 * - 0 on success
-	 * - LIBUSB_ERROR_NOT_FOUND if no kernel driver was active
-	 * - LIBUSB_ERROR_INVALID_PARAM if the interface does not exist
-	 * - LIBUSB_ERROR_NO_DEVICE if the device has been disconnected since it
-	 *   was opened
-	 * - LIBUSB_ERROR_BUSY if a program or driver has claimed the interface,
-	 *   preventing reattachment
-	 * - another LIBUSB_ERROR code on other failure
-	 */
-	int (*attach_kernel_driver)(struct libusb_device_handle *handle,
-		int interface_number);
-
-	/* Destroy a device. Optional.
-	 *
-	 * This function is called when the last reference to a device is
-	 * destroyed. It should free any resources allocated in the get_device_list
-	 * path.
-	 */
-	void (*destroy_device)(struct libusb_device *dev);
-
-	/* Submit a transfer. Your implementation should take the transfer,
-	 * morph it into whatever form your platform requires, and submit it
-	 * asynchronously.
-	 *
-	 * This function must not block.
-	 *
-	 * Return:
-	 * - 0 on success
-	 * - LIBUSB_ERROR_NO_DEVICE if the device has been disconnected
-	 * - another LIBUSB_ERROR code on other failure
-	 */
-	int (*submit_transfer)(struct usbi_transfer *itransfer);
-
-	/* Cancel a previously submitted transfer.
-	 *
-	 * This function must not block. The transfer cancellation must complete
-	 * later, resulting in a call to usbi_handle_transfer_cancellation()
-	 * from the context of handle_events.
-	 */
-	int (*cancel_transfer)(struct usbi_transfer *itransfer);
-
-	/* Clear a transfer as if it has completed or cancelled, but do not
-	 * report any completion/cancellation to the library. You should free
-	 * all private data from the transfer as if you were just about to report
-	 * completion or cancellation.
-	 *
-	 * This function might seem a bit out of place. It is used when libusb
-	 * detects a disconnected device - it calls this function for all pending
-	 * transfers before reporting completion (with the disconnect code) to
-	 * the user. Maybe we can improve upon this internal interface in future.
-	 */
-	void (*clear_transfer_priv)(struct usbi_transfer *itransfer);
-
-	/* Handle any pending events. This involves monitoring any active
-	 * transfers and processing their completion or cancellation.
-	 *
-	 * The function is passed an array of pollfd structures (size nfds)
-	 * as a result of the poll() system call. The num_ready parameter
-	 * indicates the number of file descriptors that have reported events
-	 * (i.e. the poll() return value). This should be enough information
-	 * for you to determine which actions need to be taken on the currently
-	 * active transfers.
-	 *
-	 * For any cancelled transfers, call usbi_handle_transfer_cancellation().
-	 * For completed transfers, call usbi_handle_transfer_completion().
-	 * For control/bulk/interrupt transfers, populate the "transferred"
-	 * element of the appropriate usbi_transfer structure before calling the
-	 * above functions. For isochronous transfers, populate the status and
-	 * transferred fields of the iso packet descriptors of the transfer.
-	 *
-	 * This function should also be able to detect disconnection of the
-	 * device, reporting that situation with usbi_handle_disconnect().
-	 *
-	 * When processing an event related to a transfer, you probably want to
-	 * take usbi_transfer.lock to prevent races. See the documentation for
-	 * the usbi_transfer structure.
-	 *
-	 * Return 0 on success, or a LIBUSB_ERROR code on failure.
-	 */
-	int (*handle_events)(struct libusb_context *ctx,
-		struct pollfd *fds, POLL_NFDS_TYPE nfds, int num_ready);
-
-	/* Get time from specified clock. At least two clocks must be implemented
-	   by the backend: USBI_CLOCK_REALTIME, and USBI_CLOCK_MONOTONIC.
-
-	   Description of clocks:
-	     USBI_CLOCK_REALTIME : clock returns time since system epoch.
-	     USBI_CLOCK_MONOTONIC: clock returns time since unspecified start
-	                             time (usually boot).
-	 */
-	int (*clock_gettime)(int clkid, struct timespec *tp);
-
-#ifdef USBI_TIMERFD_AVAILABLE
-	/* clock ID of the clock that should be used for timerfd */
-	clockid_t (*get_timerfd_clockid)(void);
-#endif
-
-	/* Number of bytes to reserve for per-device private backend data.
-	 * This private data area is accessible through the "os_priv" field of
-	 * struct libusb_device. */
-	size_t device_priv_size;
-
-	/* Number of bytes to reserve for per-handle private backend data.
-	 * This private data area is accessible through the "os_priv" field of
-	 * struct libusb_device. */
-	size_t device_handle_priv_size;
-
-	/* Number of bytes to reserve for per-transfer private backend data.
-	 * This private data area is accessible by calling
-	 * usbi_transfer_get_os_priv() on the appropriate usbi_transfer instance.
-	 */
-	size_t transfer_priv_size;
-
-	/* Mumber of additional bytes for os_priv for each iso packet.
-	 * Can your backend use this? */
-	/* FIXME: linux can't use this any more. if other OS's cannot either,
-	 * then remove this */
-	size_t add_iso_packet_size;
-};
-
-extern const struct usbi_os_backend * const usbi_backend;
-
-extern const struct usbi_os_backend linux_usbfs_backend;
-extern const struct usbi_os_backend darwin_backend;
-extern const struct usbi_os_backend windows_backend;
-
-#endif
-
diff --git a/third_party/libusb/libusb/os/darwin_usb.c b/third_party/libusb/libusb/os/darwin_usb.c
deleted file mode 100644
index 0af4e3c..0000000
--- a/third_party/libusb/libusb/os/darwin_usb.c
+++ /dev/null
@@ -1,1751 +0,0 @@
-/*
- * darwin backend for libusb 1.0
- * Copyright (C) 2008-2011 Nathan Hjelm <hjelmn@users.sourceforge.net>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#include <config.h>
-#include <ctype.h>
-#include <dirent.h>
-#include <errno.h>
-#include <fcntl.h>
-#include <pthread.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/ioctl.h>
-#include <sys/stat.h>
-#include <sys/types.h>
-#include <unistd.h>
-
-#include <mach/clock.h>
-#include <mach/clock_types.h>
-#include <mach/mach_host.h>
-#include <mach/mach_port.h>
-
-#include <AvailabilityMacros.h>
-#if MAC_OS_X_VERSION_MIN_REQUIRED >= 1060
-  #include <objc/objc-auto.h>
-#endif
-
-#include <IOKit/IOCFBundle.h>
-#include <IOKit/usb/IOUSBLib.h>
-#include <IOKit/IOCFPlugIn.h>
-
-#include "darwin_usb.h"
-
-/* async event thread */
-static pthread_mutex_t libusb_darwin_at_mutex;
-static pthread_cond_t  libusb_darwin_at_cond;
-
-static clock_serv_t clock_realtime;
-static clock_serv_t clock_monotonic;
-
-static CFRunLoopRef libusb_darwin_acfl = NULL; /* async cf loop */
-static int initCount = 0;
-
-/* async event thread */
-static pthread_t libusb_darwin_at;
-
-static int darwin_get_config_descriptor(struct libusb_device *dev, uint8_t config_index, unsigned char *buffer, size_t len, int *host_endian);
-static int darwin_claim_interface(struct libusb_device_handle *dev_handle, int iface);
-static int darwin_release_interface(struct libusb_device_handle *dev_handle, int iface);
-static int darwin_reset_device(struct libusb_device_handle *dev_handle);
-static void darwin_async_io_callback (void *refcon, IOReturn result, void *arg0);
-
-static const char *darwin_error_str (int result) {
-  switch (result) {
-  case kIOReturnSuccess:
-    return "no error";
-  case kIOReturnNotOpen:
-    return "device not opened for exclusive access";
-  case kIOReturnNoDevice:
-    return "no connection to an IOService";
-  case kIOUSBNoAsyncPortErr:
-    return "no async port has been opened for interface";
-  case kIOReturnExclusiveAccess:
-    return "another process has device opened for exclusive access";
-  case kIOUSBPipeStalled:
-    return "pipe is stalled";
-  case kIOReturnError:
-    return "could not establish a connection to the Darwin kernel";
-  case kIOUSBTransactionTimeout:
-    return "transaction timed out";
-  case kIOReturnBadArgument:
-    return "invalid argument";
-  case kIOReturnAborted:
-    return "transaction aborted";
-  case kIOReturnNotResponding:
-    return "device not responding";
-  case kIOReturnOverrun:
-    return "data overrun";
-  case kIOReturnCannotWire:
-    return "physical memory can not be wired down";
-  default:
-    return "unknown error";
-  }
-}
-
-static int darwin_to_libusb (int result) {
-  switch (result) {
-  case kIOReturnUnderrun:
-  case kIOReturnSuccess:
-    return LIBUSB_SUCCESS;
-  case kIOReturnNotOpen:
-  case kIOReturnNoDevice:
-    return LIBUSB_ERROR_NO_DEVICE;
-  case kIOReturnExclusiveAccess:
-    return LIBUSB_ERROR_ACCESS;
-  case kIOUSBPipeStalled:
-    return LIBUSB_ERROR_PIPE;
-  case kIOReturnBadArgument:
-    return LIBUSB_ERROR_INVALID_PARAM;
-  case kIOUSBTransactionTimeout:
-    return LIBUSB_ERROR_TIMEOUT;
-  case kIOReturnNotResponding:
-  case kIOReturnAborted:
-  case kIOReturnError:
-  case kIOUSBNoAsyncPortErr:
-  default:
-    return LIBUSB_ERROR_OTHER;
-  }
-}
-
-
-static int ep_to_pipeRef(struct libusb_device_handle *dev_handle, uint8_t ep, uint8_t *pipep, uint8_t *ifcp) {
-  struct darwin_device_handle_priv *priv = (struct darwin_device_handle_priv *)dev_handle->os_priv;
-
-  /* current interface */
-  struct darwin_interface *cInterface;
-
-  int8_t i, iface;
-
-  usbi_info (HANDLE_CTX(dev_handle), "converting ep address 0x%02x to pipeRef and interface", ep);
-
-  for (iface = 0 ; iface < USB_MAXINTERFACES ; iface++) {
-    cInterface = &priv->interfaces[iface];
-
-    if (dev_handle->claimed_interfaces & (1 << iface)) {
-      for (i = 0 ; i < cInterface->num_endpoints ; i++) {
-	if (cInterface->endpoint_addrs[i] == ep) {
-	  *pipep = i + 1;
-	  *ifcp = iface;
-	  usbi_info (HANDLE_CTX(dev_handle), "pipe %d on interface %d matches", *pipep, *ifcp);
-	  return 0;
-	}
-      }
-    }
-  }
-
-  /* No pipe found with the correct endpoint address */
-  usbi_warn (HANDLE_CTX(dev_handle), "no pipeRef found with endpoint address 0x%02x.", ep);
-
-  return -1;
-}
-
-static int usb_setup_device_iterator (io_iterator_t *deviceIterator, long location) {
-  CFMutableDictionaryRef matchingDict = IOServiceMatching(kIOUSBDeviceClassName);
-
-  if (!matchingDict)
-    return kIOReturnError;
-
-  if (location) {
-    CFMutableDictionaryRef propertyMatchDict = CFDictionaryCreateMutable(kCFAllocatorDefault, 0,
-                                                                         &kCFTypeDictionaryKeyCallBacks,
-                                                                         &kCFTypeDictionaryValueCallBacks);
-
-    if (propertyMatchDict) {
-      CFTypeRef locationCF = CFNumberCreate (NULL, kCFNumberLongType, &location);
-
-      CFDictionarySetValue (propertyMatchDict, CFSTR(kUSBDevicePropertyLocationID), locationCF);
-      /* release our reference to the CFNumber (CFDictionarySetValue retains it) */
-      CFRelease (locationCF);
-
-      CFDictionarySetValue (matchingDict, CFSTR(kIOPropertyMatchKey), propertyMatchDict);
-      /* release out reference to the CFMutableDictionaryRef (CFDictionarySetValue retains it) */
-      CFRelease (propertyMatchDict);
-    }
-    /* else we can still proceed as long as the caller accounts for the possibility of other devices in the iterator */
-  }
-
-  return IOServiceGetMatchingServices(kIOMasterPortDefault, matchingDict, deviceIterator);
-}
-
-static usb_device_t **usb_get_next_device (io_iterator_t deviceIterator, UInt32 *locationp) {
-  io_cf_plugin_ref_t *plugInInterface = NULL;
-  usb_device_t **device;
-  io_service_t usbDevice;
-  long result;
-  SInt32 score;
-
-  if (!IOIteratorIsValid (deviceIterator))
-    return NULL;
-
-
-  while ((usbDevice = IOIteratorNext(deviceIterator))) {
-    result = IOCreatePlugInInterfaceForService(usbDevice, kIOUSBDeviceUserClientTypeID,
-					       kIOCFPlugInInterfaceID, &plugInInterface,
-					       &score);
-
-    /* we are done with the usb_device_t */
-    (void)IOObjectRelease(usbDevice);
-    if (kIOReturnSuccess == result && plugInInterface)
-      break;
-
-    usbi_dbg ("libusb/darwin.c usb_get_next_device: could not set up plugin for service: %s\n", darwin_error_str (result));
-  }
-
-  if (!usbDevice)
-    return NULL;
-
-  (void)(*plugInInterface)->QueryInterface(plugInInterface, CFUUIDGetUUIDBytes(DeviceInterfaceID),
-					   (LPVOID)&device);
-
-  (*plugInInterface)->Stop(plugInInterface);
-  IODestroyPlugInInterface (plugInInterface);
-
-  /* get the location from the device */
-  if (locationp)
-    (*(device))->GetLocationID(device, locationp);
-
-  return device;
-}
-
-static kern_return_t darwin_get_device (uint32_t dev_location, usb_device_t ***darwin_device) {
-  kern_return_t kresult;
-  UInt32        location;
-  io_iterator_t deviceIterator;
-
-  kresult = usb_setup_device_iterator (&deviceIterator, dev_location);
-  if (kresult)
-    return kresult;
-
-  /* This port of libusb uses locations to keep track of devices. */
-  while ((*darwin_device = usb_get_next_device (deviceIterator, &location)) != NULL) {
-    if (location == dev_location)
-      break;
-
-    (**darwin_device)->Release(*darwin_device);
-  }
-
-  IOObjectRelease (deviceIterator);
-
-  if (!(*darwin_device))
-    return kIOReturnNoDevice;
-
-  return kIOReturnSuccess;
-}
-
-
-
-static void darwin_devices_detached (void *ptr, io_iterator_t rem_devices) {
-  struct libusb_context *ctx = (struct libusb_context *)ptr;
-  struct libusb_device_handle *handle;
-  struct darwin_device_priv *dpriv;
-  struct darwin_device_handle_priv *priv;
-
-  io_service_t device;
-  long location;
-  bool locationValid;
-  CFTypeRef locationCF;
-  UInt32 message;
-
-  usbi_info (ctx, "a device has been detached");
-
-  while ((device = IOIteratorNext (rem_devices)) != 0) {
-    /* get the location from the i/o registry */
-    locationCF = IORegistryEntryCreateCFProperty (device, CFSTR(kUSBDevicePropertyLocationID), kCFAllocatorDefault, 0);
-
-    IOObjectRelease (device);
-
-    if (!locationCF)
-      continue;
-
-    locationValid = CFGetTypeID(locationCF) == CFNumberGetTypeID() &&
-	    CFNumberGetValue(locationCF, kCFNumberLongType, &location);
-
-    CFRelease (locationCF);
-
-    if (!locationValid)
-      continue;
-
-    usbi_mutex_lock(&ctx->open_devs_lock);
-    list_for_each_entry(handle, &ctx->open_devs, list, struct libusb_device_handle) {
-      dpriv = (struct darwin_device_priv *)handle->dev->os_priv;
-
-      /* the device may have been opened several times. write to each handle's event descriptor */
-      if (dpriv->location == location  && handle->os_priv) {
-	priv  = (struct darwin_device_handle_priv *)handle->os_priv;
-
-	message = MESSAGE_DEVICE_GONE;
-	write (priv->fds[1], &message, sizeof (message));
-      }
-    }
-
-    usbi_mutex_unlock(&ctx->open_devs_lock);
-  }
-}
-
-static void darwin_clear_iterator (io_iterator_t iter) {
-  io_service_t device;
-
-  while ((device = IOIteratorNext (iter)) != 0)
-    IOObjectRelease (device);
-}
-
-static void *event_thread_main (void *arg0) {
-  IOReturn kresult;
-  struct libusb_context *ctx = (struct libusb_context *)arg0;
-  CFRunLoopRef runloop;
-
-  /* Tell the Objective-C garbage collector about this thread.
-     This is required because, unlike NSThreads, pthreads are
-     not automatically registered. Although we don't use
-     Objective-C, we use CoreFoundation, which does. */
-#if MAC_OS_X_VERSION_MIN_REQUIRED >= 1060
-  objc_registerThreadWithCollector();
-#endif
-
-  /* hotplug (device removal) source */
-  CFRunLoopSourceRef     libusb_notification_cfsource;
-  io_notification_port_t libusb_notification_port;
-  io_iterator_t          libusb_rem_device_iterator;
-
-  usbi_info (ctx, "creating hotplug event source");
-
-  runloop = CFRunLoopGetCurrent ();
-  CFRetain (runloop);
-
-  /* add the notification port to the run loop */
-  libusb_notification_port     = IONotificationPortCreate (kIOMasterPortDefault);
-  libusb_notification_cfsource = IONotificationPortGetRunLoopSource (libusb_notification_port);
-  CFRunLoopAddSource(CFRunLoopGetCurrent (), libusb_notification_cfsource, kCFRunLoopDefaultMode);
-
-  /* create notifications for removed devices */
-  kresult = IOServiceAddMatchingNotification (libusb_notification_port, kIOTerminatedNotification,
-					      IOServiceMatching(kIOUSBDeviceClassName),
-					      (IOServiceMatchingCallback)darwin_devices_detached,
-					      (void *)ctx, &libusb_rem_device_iterator);
-
-  if (kresult != kIOReturnSuccess) {
-    usbi_err (ctx, "could not add hotplug event source: %s", darwin_error_str (kresult));
-
-    pthread_exit (NULL);
-  }
-
-  /* arm notifiers */
-  darwin_clear_iterator (libusb_rem_device_iterator);
-
-  usbi_info (ctx, "thread ready to receive events");
-
-  /* let the main thread know about the async runloop */
-  libusb_darwin_acfl = CFRunLoopGetCurrent ();
-
-  /* signal the main thread */
-  pthread_mutex_lock (&libusb_darwin_at_mutex);
-  pthread_cond_signal (&libusb_darwin_at_cond);
-  pthread_mutex_unlock (&libusb_darwin_at_mutex);
-
-  /* run the runloop */
-  CFRunLoopRun();
-
-  usbi_info (ctx, "thread exiting");
-
-  /* delete notification port */
-  IONotificationPortDestroy (libusb_notification_port);
-  IOObjectRelease (libusb_rem_device_iterator);
-
-  CFRelease (runloop);
-
-  libusb_darwin_acfl = NULL;
-
-  pthread_exit (NULL);
-}
-
-static int darwin_init(struct libusb_context *ctx) {
-  host_name_port_t host_self;
-
-  if (!(initCount++)) {
-    /* create the clocks that will be used */
-
-    host_self = mach_host_self();
-    host_get_clock_service(host_self, CALENDAR_CLOCK, &clock_realtime);
-    host_get_clock_service(host_self, SYSTEM_CLOCK, &clock_monotonic);
-    mach_port_deallocate(mach_task_self(), host_self);
-
-    pthread_mutex_init (&libusb_darwin_at_mutex, NULL);
-    pthread_cond_init (&libusb_darwin_at_cond, NULL);
-
-    pthread_create (&libusb_darwin_at, NULL, event_thread_main, (void *)ctx);
-
-    pthread_mutex_lock (&libusb_darwin_at_mutex);
-    while (!libusb_darwin_acfl)
-      pthread_cond_wait (&libusb_darwin_at_cond, &libusb_darwin_at_mutex);
-    pthread_mutex_unlock (&libusb_darwin_at_mutex);
-  }
-
-  return 0;
-}
-
-static void darwin_exit (void) {
-  if (!(--initCount)) {
-    mach_port_deallocate(mach_task_self(), clock_realtime);
-    mach_port_deallocate(mach_task_self(), clock_monotonic);
-
-    /* stop the async runloop */
-    CFRunLoopStop (libusb_darwin_acfl);
-    pthread_join (libusb_darwin_at, NULL);
-  }
-}
-
-static int darwin_get_device_descriptor(struct libusb_device *dev, unsigned char *buffer, int *host_endian) {
-  struct darwin_device_priv *priv = (struct darwin_device_priv *)dev->os_priv;
-
-  /* return cached copy */
-  memmove (buffer, &(priv->dev_descriptor), DEVICE_DESC_LENGTH);
-
-  *host_endian = 0;
-
-  return 0;
-}
-
-static int get_configuration_index (struct libusb_device *dev, int config_value) {
-  struct darwin_device_priv *priv = (struct darwin_device_priv *)dev->os_priv;
-  UInt8 i, numConfig;
-  IOUSBConfigurationDescriptorPtr desc;
-  IOReturn kresult;
-
-  /* is there a simpler way to determine the index? */
-  kresult = (*(priv->device))->GetNumberOfConfigurations (priv->device, &numConfig);
-  if (kresult != kIOReturnSuccess)
-    return darwin_to_libusb (kresult);
-
-  for (i = 0 ; i < numConfig ; i++) {
-    (*(priv->device))->GetConfigurationDescriptorPtr (priv->device, i, &desc);
-
-    if (desc->bConfigurationValue == config_value)
-      return i;
-  }
-
-  /* configuration not found */
-  return LIBUSB_ERROR_OTHER;
-}
-
-static int darwin_get_active_config_descriptor(struct libusb_device *dev, unsigned char *buffer, size_t len, int *host_endian) {
-  struct darwin_device_priv *priv = (struct darwin_device_priv *)dev->os_priv;
-  int config_index;
-
-  if (0 == priv->active_config)
-    return LIBUSB_ERROR_INVALID_PARAM;
-
-  config_index = get_configuration_index (dev, priv->active_config);
-  if (config_index < 0)
-    return config_index;
-
-  return darwin_get_config_descriptor (dev, config_index, buffer, len, host_endian);
-}
-
-static int darwin_get_config_descriptor(struct libusb_device *dev, uint8_t config_index, unsigned char *buffer, size_t len, int *host_endian) {
-  struct darwin_device_priv *priv = (struct darwin_device_priv *)dev->os_priv;
-  IOUSBConfigurationDescriptorPtr desc;
-  IOReturn kresult;
-  usb_device_t **device = NULL;
-
-  if (!priv)
-    return LIBUSB_ERROR_OTHER;
-
-  if (!priv->device) {
-    kresult = darwin_get_device (priv->location, &device);
-    if (kresult || !device) {
-      usbi_err (DEVICE_CTX (dev), "could not find device: %s", darwin_error_str (kresult));
-
-      return darwin_to_libusb (kresult);
-    }
-
-    /* don't have to open the device to get a config descriptor */
-  } else
-    device = priv->device;
-
-  kresult = (*device)->GetConfigurationDescriptorPtr (device, config_index, &desc);
-  if (kresult == kIOReturnSuccess) {
-    /* copy descriptor */
-    if (libusb_le16_to_cpu(desc->wTotalLength) < len)
-      len = libusb_le16_to_cpu(desc->wTotalLength);
-
-    memmove (buffer, desc, len);
-
-    /* GetConfigurationDescriptorPtr returns the descriptor in USB bus order */
-    *host_endian = 0;
-  }
-
-  if (!priv->device)
-    (*device)->Release (device);
-
-  return darwin_to_libusb (kresult);
-}
-
-/* check whether the os has configured the device */
-static int darwin_check_configuration (struct libusb_context *ctx, struct libusb_device *dev, usb_device_t **darwin_device) {
-  struct darwin_device_priv *priv = (struct darwin_device_priv *)dev->os_priv;
-
-  IOUSBConfigurationDescriptorPtr configDesc;
-  IOUSBFindInterfaceRequest request;
-  kern_return_t             kresult;
-  io_iterator_t             interface_iterator;
-  io_service_t              firstInterface;
-
-  if (priv->dev_descriptor.bNumConfigurations < 1) {
-    usbi_err (ctx, "device has no configurations");
-    return LIBUSB_ERROR_OTHER; /* no configurations at this speed so we can't use it */
-  }
-
-  /* find the first configuration */
-  kresult = (*darwin_device)->GetConfigurationDescriptorPtr (darwin_device, 0, &configDesc);
-  priv->first_config = (kIOReturnSuccess == kresult) ? configDesc->bConfigurationValue : 1;
-
-  /* check if the device is already configured. there is probably a better way than iterating over the
-     to accomplish this (the trick is we need to avoid a call to GetConfigurations since buggy devices
-     might lock up on the device request) */
-
-  /* Setup the Interface Request */
-  request.bInterfaceClass    = kIOUSBFindInterfaceDontCare;
-  request.bInterfaceSubClass = kIOUSBFindInterfaceDontCare;
-  request.bInterfaceProtocol = kIOUSBFindInterfaceDontCare;
-  request.bAlternateSetting  = kIOUSBFindInterfaceDontCare;
-
-  kresult = (*(darwin_device))->CreateInterfaceIterator(darwin_device, &request, &interface_iterator);
-  if (kresult)
-    return darwin_to_libusb (kresult);
-
-  /* iterate once */
-  firstInterface = IOIteratorNext(interface_iterator);
-
-  /* done with the interface iterator */
-  IOObjectRelease(interface_iterator);
-
-  if (firstInterface) {
-    IOObjectRelease (firstInterface);
-
-    /* device is configured */
-    if (priv->dev_descriptor.bNumConfigurations == 1)
-      /* to avoid problems with some devices get the configurations value from the configuration descriptor */
-      priv->active_config = priv->first_config;
-    else
-      /* devices with more than one configuration should work with GetConfiguration */
-      (*darwin_device)->GetConfiguration (darwin_device, &priv->active_config);
-  } else
-    /* not configured */
-    priv->active_config = 0;
-  
-  usbi_info (ctx, "active config: %u, first config: %u", priv->active_config, priv->first_config);
-
-  return 0;
-}
-
-static int darwin_cache_device_descriptor (struct libusb_context *ctx, struct libusb_device *dev, usb_device_t **device) {
-  struct darwin_device_priv *priv;
-  int retries = 5, delay = 30000;
-  int unsuspended = 0, try_unsuspend = 1, try_reconfigure = 1;
-  int is_open = 0;
-  int ret = 0, ret2;
-  IOUSBDevRequest req;
-  UInt8 bDeviceClass;
-  UInt16 idProduct, idVendor;
-
-  (*device)->GetDeviceClass (device, &bDeviceClass);
-  (*device)->GetDeviceProduct (device, &idProduct);
-  (*device)->GetDeviceVendor (device, &idVendor);
-
-  priv = (struct darwin_device_priv *)dev->os_priv;
-
-  /* try to open the device (we can usually continue even if this fails) */
-  is_open = ((*device)->USBDeviceOpenSeize(device) == kIOReturnSuccess);
-
-  /**** retrieve device descriptor ****/
-  do {
-    /* Set up request for device descriptor */
-    memset (&(priv->dev_descriptor), 0, sizeof(IOUSBDeviceDescriptor));
-    req.bmRequestType = USBmakebmRequestType(kUSBIn, kUSBStandard, kUSBDevice);
-    req.bRequest      = kUSBRqGetDescriptor;
-    req.wValue        = kUSBDeviceDesc << 8;
-    req.wIndex        = 0;
-    req.wLength       = sizeof(priv->dev_descriptor);
-    req.pData         = &(priv->dev_descriptor);
-
-    /* according to Apple's documentation the device must be open for DeviceRequest but we may not be able to open some
-     * devices and Apple's USB Prober doesn't bother to open the device before issuing a descriptor request.  Still,
-     * to follow the spec as closely as possible, try opening the device */
-
-    ret = (*(device))->DeviceRequest (device, &req);
-
-    if (kIOReturnOverrun == ret && kUSBDeviceDesc == priv->dev_descriptor.bDescriptorType)
-      /* received an overrun error but we still received a device descriptor */
-      ret = kIOReturnSuccess;
-
-    if (kIOReturnSuccess == ret && (0 == priv->dev_descriptor.idProduct ||
-				    0 == priv->dev_descriptor.bNumConfigurations ||
-				    0 == priv->dev_descriptor.bcdUSB)) {
-      /* work around for incorrectly configured devices */
-      if (try_reconfigure && is_open) {
-	usbi_dbg("descriptor appears to be invalid. resetting configuration before trying again...");
-
-	/* set the first configuration */
-	(*device)->SetConfiguration(device, 1);
-
-	/* don't try to reconfigure again */
-	try_reconfigure = 0;
-      }
-
-      ret = kIOUSBPipeStalled;
-    }
-
-    if (kIOReturnSuccess != ret && is_open && try_unsuspend) {
-      /* device may be suspended. unsuspend it and try again */
-#if DeviceVersion >= 320
-      UInt32 info;
-
-      /* IOUSBFamily 320+ provides a way to detect device suspension but earlier versions do not */
-      (void)(*device)->GetUSBDeviceInformation (device, &info);
-
-      try_unsuspend = info & (1 << kUSBInformationDeviceIsSuspendedBit);
-#endif
-
-      if (try_unsuspend) {
-	/* resume the device */
-	ret2 = (*device)->USBDeviceSuspend (device, 0);
-	if (kIOReturnSuccess != ret2) {
-	  /* prevent log spew from poorly behaving devices.  this indicates the
-	     os actually had trouble communicating with the device */
-	  usbi_dbg("could not retrieve device descriptor. failed to unsuspend: %s",darwin_error_str(ret2));
-	} else
-	  unsuspended = 1;
-
-	try_unsuspend = 0;
-      }
-    }
-
-    if (kIOReturnSuccess != ret) {
-      usbi_dbg("kernel responded with code: 0x%08x. sleeping for %d ms before trying again", ret, delay/1000);
-      /* sleep for a little while before trying again */
-      usleep (delay);
-    }
-  } while (kIOReturnSuccess != ret && retries--);
-
-  if (unsuspended)
-    /* resuspend the device */
-    (void)(*device)->USBDeviceSuspend (device, 1);
-
-  if (is_open)
-    (void) (*device)->USBDeviceClose (device);
-
-  if (ret != kIOReturnSuccess) {
-    /* a debug message was already printed out for this error */
-    if (LIBUSB_CLASS_HUB == bDeviceClass)
-      usbi_dbg ("could not retrieve device descriptor %.4x:%.4x: %s. skipping device", idVendor, idProduct, darwin_error_str (ret));
-    else
-      usbi_warn (ctx, "could not retrieve device descriptor %.4x:%.4x: %s. skipping device", idVendor, idProduct, darwin_error_str (ret));
-
-    return -1;
-  }
-
-  usbi_dbg ("device descriptor:");
-  usbi_dbg (" bDescriptorType:    0x%02x", priv->dev_descriptor.bDescriptorType);
-  usbi_dbg (" bcdUSB:             0x%04x", priv->dev_descriptor.bcdUSB);
-  usbi_dbg (" bDeviceClass:       0x%02x", priv->dev_descriptor.bDeviceClass);
-  usbi_dbg (" bDeviceSubClass:    0x%02x", priv->dev_descriptor.bDeviceSubClass);
-  usbi_dbg (" bDeviceProtocol:    0x%02x", priv->dev_descriptor.bDeviceProtocol);
-  usbi_dbg (" bMaxPacketSize0:    0x%02x", priv->dev_descriptor.bMaxPacketSize0);
-  usbi_dbg (" idVendor:           0x%04x", priv->dev_descriptor.idVendor);
-  usbi_dbg (" idProduct:          0x%04x", priv->dev_descriptor.idProduct);
-  usbi_dbg (" bcdDevice:          0x%04x", priv->dev_descriptor.bcdDevice);
-  usbi_dbg (" iManufacturer:      0x%02x", priv->dev_descriptor.iManufacturer);
-  usbi_dbg (" iProduct:           0x%02x", priv->dev_descriptor.iProduct);
-  usbi_dbg (" iSerialNumber:      0x%02x", priv->dev_descriptor.iSerialNumber);
-  usbi_dbg (" bNumConfigurations: 0x%02x", priv->dev_descriptor.bNumConfigurations);
-
-  /* catch buggy hubs (which appear to be virtual). Apple's own USB prober has problems with these devices. */
-  if (libusb_le16_to_cpu (priv->dev_descriptor.idProduct) != idProduct) {
-    /* not a valid device */
-    usbi_warn (ctx, "idProduct from iokit (%04x) does not match idProduct in descriptor (%04x). skipping device",
-	       idProduct, libusb_le16_to_cpu (priv->dev_descriptor.idProduct));
-    return -1;
-  }
-
-  return 0;
-}
-
-static int process_new_device (struct libusb_context *ctx, usb_device_t **device, UInt32 locationID, struct discovered_devs **_discdevs) {
-  struct darwin_device_priv *priv;
-  struct libusb_device *dev;
-  struct discovered_devs *discdevs;
-  UInt16                address;
-  UInt8                 devSpeed;
-  int ret = 0, need_unref = 0;
-
-  do {
-    dev = usbi_get_device_by_session_id(ctx, locationID);
-    if (!dev) {
-      usbi_info (ctx, "allocating new device for location 0x%08x", locationID);
-      dev = usbi_alloc_device(ctx, locationID);
-      need_unref = 1;
-    } else
-      usbi_info (ctx, "using existing device for location 0x%08x", locationID);
-
-    if (!dev) {
-      ret = LIBUSB_ERROR_NO_MEM;
-      break;
-    }
-
-    priv = (struct darwin_device_priv *)dev->os_priv;
-
-    (*device)->GetDeviceAddress (device, (USBDeviceAddress *)&address);
-
-    ret = darwin_cache_device_descriptor (ctx, dev, device);
-    if (ret < 0)
-      break;
-
-    /* check current active configuration (and cache the first configuration value-- which may be used by claim_interface) */
-    ret = darwin_check_configuration (ctx, dev, device);
-    if (ret < 0)
-      break;
-
-    dev->bus_number     = locationID >> 24;
-    dev->device_address = address;
-
-    (*device)->GetDeviceSpeed (device, &devSpeed);
-
-    switch (devSpeed) {
-    case kUSBDeviceSpeedLow: dev->speed = LIBUSB_SPEED_LOW; break;
-    case kUSBDeviceSpeedFull: dev->speed = LIBUSB_SPEED_FULL; break;
-    case kUSBDeviceSpeedHigh: dev->speed = LIBUSB_SPEED_HIGH; break;
-    default:
-      usbi_warn (ctx, "Got unknown device speed %d", devSpeed);
-    }
-
-    /* save our location, we'll need this later */
-    priv->location = locationID;
-    snprintf(priv->sys_path, 20, "%03i-%04x-%04x-%02x-%02x", address, priv->dev_descriptor.idVendor, priv->dev_descriptor.idProduct,
-	     priv->dev_descriptor.bDeviceClass, priv->dev_descriptor.bDeviceSubClass);
-
-    ret = usbi_sanitize_device (dev);
-    if (ret < 0)
-      break;
-
-    /* append the device to the list of discovered devices */
-    discdevs = discovered_devs_append(*_discdevs, dev);
-    if (!discdevs) {
-      ret = LIBUSB_ERROR_NO_MEM;
-      break;
-    }
-
-    *_discdevs = discdevs;
-
-    usbi_info (ctx, "found device with address %d at %s", dev->device_address, priv->sys_path);
-  } while (0);
-
-  if (need_unref)
-    libusb_unref_device(dev);
-
-  return ret;
-}
-
-static int darwin_get_device_list(struct libusb_context *ctx, struct discovered_devs **_discdevs) {
-  io_iterator_t        deviceIterator;
-  usb_device_t         **device;
-  kern_return_t        kresult;
-  UInt32               location;
-
-  kresult = usb_setup_device_iterator (&deviceIterator, 0);
-  if (kresult != kIOReturnSuccess)
-    return darwin_to_libusb (kresult);
-
-  while ((device = usb_get_next_device (deviceIterator, &location)) != NULL) {
-    (void) process_new_device (ctx, device, location, _discdevs);
-
-    (*(device))->Release(device);
-  }
-
-  IOObjectRelease(deviceIterator);
-
-  return 0;
-}
-
-static int darwin_open (struct libusb_device_handle *dev_handle) {
-  struct darwin_device_handle_priv *priv = (struct darwin_device_handle_priv *)dev_handle->os_priv;
-  struct darwin_device_priv *dpriv = (struct darwin_device_priv *)dev_handle->dev->os_priv;
-  usb_device_t  **darwin_device;
-  IOReturn kresult;
-
-  if (0 == dpriv->open_count) {
-    kresult = darwin_get_device (dpriv->location, &darwin_device);
-    if (kresult) {
-      usbi_err (HANDLE_CTX (dev_handle), "could not find device: %s", darwin_error_str (kresult));
-      return darwin_to_libusb (kresult);
-    }
-
-    dpriv->device = darwin_device;
-
-    /* try to open the device */
-    kresult = (*(dpriv->device))->USBDeviceOpenSeize (dpriv->device);
-
-    if (kresult != kIOReturnSuccess) {
-      usbi_err (HANDLE_CTX (dev_handle), "USBDeviceOpen: %s", darwin_error_str(kresult));
-
-      switch (kresult) {
-      case kIOReturnExclusiveAccess:
-	/* it is possible to perform some actions on a device that is not open so do not return an error */
-	priv->is_open = 0;
-
-	break;
-      default:
-	(*(dpriv->device))->Release (dpriv->device);
-	dpriv->device = NULL;
-	return darwin_to_libusb (kresult);
-      }
-    } else {
-      /* create async event source */
-      kresult = (*(dpriv->device))->CreateDeviceAsyncEventSource (dpriv->device, &priv->cfSource);
-      if (kresult != kIOReturnSuccess) {
-	usbi_err (HANDLE_CTX (dev_handle), "CreateDeviceAsyncEventSource: %s", darwin_error_str(kresult));
-
-	(*(dpriv->device))->USBDeviceClose (dpriv->device);
-	(*(dpriv->device))->Release (dpriv->device);
-
-	dpriv->device = NULL;
-	return darwin_to_libusb (kresult);
-      }
-
-      priv->is_open = 1;
-
-      CFRetain (libusb_darwin_acfl);
-
-      /* add the cfSource to the aync run loop */
-      CFRunLoopAddSource(libusb_darwin_acfl, priv->cfSource, kCFRunLoopCommonModes);
-    }
-  }
-
-  /* device opened successfully */
-  dpriv->open_count++;
-
-  /* create a file descriptor for notifications */
-  pipe (priv->fds);
-
-  /* set the pipe to be non-blocking */
-  fcntl (priv->fds[1], F_SETFD, O_NONBLOCK);
-
-  usbi_add_pollfd(HANDLE_CTX(dev_handle), priv->fds[0], POLLIN);
-
-  usbi_info (HANDLE_CTX (dev_handle), "device open for access");
-
-  return 0;
-}
-
-static void darwin_close (struct libusb_device_handle *dev_handle) {
-  struct darwin_device_handle_priv *priv = (struct darwin_device_handle_priv *)dev_handle->os_priv;
-  struct darwin_device_priv *dpriv = (struct darwin_device_priv *)dev_handle->dev->os_priv;
-  IOReturn kresult;
-  int i;
-
-  if (dpriv->open_count == 0) {
-    /* something is probably very wrong if this is the case */
-    usbi_err (HANDLE_CTX (dev_handle), "Close called on a device that was not open!\n");
-    return;
-  }
-
-  dpriv->open_count--;
-
-  /* make sure all interfaces are released */
-  for (i = 0 ; i < USB_MAXINTERFACES ; i++)
-    if (dev_handle->claimed_interfaces & (1 << i))
-      libusb_release_interface (dev_handle, i);
-
-  if (0 == dpriv->open_count) {
-    if (priv->is_open) {
-      /* delete the device's async event source */
-      if (priv->cfSource) {
-	CFRunLoopRemoveSource (libusb_darwin_acfl, priv->cfSource, kCFRunLoopDefaultMode);
-	CFRelease (priv->cfSource);
-      }
-
-      /* close the device */
-      kresult = (*(dpriv->device))->USBDeviceClose(dpriv->device);
-      if (kresult) {
-	/* Log the fact that we had a problem closing the file, however failing a
-	 * close isn't really an error, so return success anyway */
-	usbi_err (HANDLE_CTX (dev_handle), "USBDeviceClose: %s", darwin_error_str(kresult));
-      }
-    }
-
-    kresult = (*(dpriv->device))->Release(dpriv->device);
-    if (kresult) {
-      /* Log the fact that we had a problem closing the file, however failing a
-       * close isn't really an error, so return success anyway */
-      usbi_err (HANDLE_CTX (dev_handle), "Release: %s", darwin_error_str(kresult));
-    }
-
-    dpriv->device = NULL;
-  }
-
-  /* file descriptors are maintained per-instance */
-  usbi_remove_pollfd (HANDLE_CTX (dev_handle), priv->fds[0]);
-  close (priv->fds[1]);
-  close (priv->fds[0]);
-
-  priv->fds[0] = priv->fds[1] = -1;
-}
-
-static int darwin_get_configuration(struct libusb_device_handle *dev_handle, int *config) {
-  struct darwin_device_priv *dpriv = (struct darwin_device_priv *)dev_handle->dev->os_priv;
-
-  *config = (int) dpriv->active_config;
-
-  return 0;
-}
-
-static int darwin_set_configuration(struct libusb_device_handle *dev_handle, int config) {
-  struct darwin_device_priv *dpriv = (struct darwin_device_priv *)dev_handle->dev->os_priv;
-  IOReturn kresult;
-  int i;
-
-  /* Setting configuration will invalidate the interface, so we need
-     to reclaim it. First, dispose of existing interfaces, if any. */
-  for (i = 0 ; i < USB_MAXINTERFACES ; i++)
-    if (dev_handle->claimed_interfaces & (1 << i))
-      darwin_release_interface (dev_handle, i);
-
-  kresult = (*(dpriv->device))->SetConfiguration (dpriv->device, config);
-  if (kresult != kIOReturnSuccess)
-    return darwin_to_libusb (kresult);
-
-  /* Reclaim any interfaces. */
-  for (i = 0 ; i < USB_MAXINTERFACES ; i++)
-    if (dev_handle->claimed_interfaces & (1 << i))
-      darwin_claim_interface (dev_handle, i);
-
-  dpriv->active_config = config;
-
-  return 0;
-}
-
-static int darwin_get_interface (usb_device_t **darwin_device, uint8_t ifc, io_service_t *usbInterfacep) {
-  IOUSBFindInterfaceRequest request;
-  uint8_t                   current_interface;
-  kern_return_t             kresult;
-  io_iterator_t             interface_iterator;
-
-  *usbInterfacep = IO_OBJECT_NULL;
-
-  /* Setup the Interface Request */
-  request.bInterfaceClass    = kIOUSBFindInterfaceDontCare;
-  request.bInterfaceSubClass = kIOUSBFindInterfaceDontCare;
-  request.bInterfaceProtocol = kIOUSBFindInterfaceDontCare;
-  request.bAlternateSetting  = kIOUSBFindInterfaceDontCare;
-
-  kresult = (*(darwin_device))->CreateInterfaceIterator(darwin_device, &request, &interface_iterator);
-  if (kresult)
-    return kresult;
-
-  for ( current_interface = 0 ; current_interface <= ifc ; current_interface++ ) {
-    *usbInterfacep = IOIteratorNext(interface_iterator);
-    if (current_interface != ifc)
-      (void) IOObjectRelease (*usbInterfacep);
-  }
-
-  /* done with the interface iterator */
-  IOObjectRelease(interface_iterator);
-
-  return 0;
-}
-
-static int get_endpoints (struct libusb_device_handle *dev_handle, int iface) {
-  struct darwin_device_handle_priv *priv = (struct darwin_device_handle_priv *)dev_handle->os_priv;
-
-  /* current interface */
-  struct darwin_interface *cInterface = &priv->interfaces[iface];
-
-  kern_return_t kresult;
-
-  u_int8_t numep, direction, number;
-  u_int8_t dont_care1, dont_care3;
-  u_int16_t dont_care2;
-  int i;
-
-  usbi_info (HANDLE_CTX (dev_handle), "building table of endpoints.");
-
-  /* retrieve the total number of endpoints on this interface */
-  kresult = (*(cInterface->interface))->GetNumEndpoints(cInterface->interface, &numep);
-  if (kresult) {
-    usbi_err (HANDLE_CTX (dev_handle), "can't get number of endpoints for interface: %s", darwin_error_str(kresult));
-    return darwin_to_libusb (kresult);
-  }
-
-  /* iterate through pipe references */
-  for (i = 1 ; i <= numep ; i++) {
-    kresult = (*(cInterface->interface))->GetPipeProperties(cInterface->interface, i, &direction, &number, &dont_care1,
-							    &dont_care2, &dont_care3);
-
-    if (kresult != kIOReturnSuccess) {
-      usbi_err (HANDLE_CTX (dev_handle), "error getting pipe information for pipe %d: %s", i, darwin_error_str(kresult));
-
-      return darwin_to_libusb (kresult);
-    }
-
-    usbi_info (HANDLE_CTX (dev_handle), "interface: %i pipe %i: dir: %i number: %i", iface, i, direction, number);
-
-    cInterface->endpoint_addrs[i - 1] = ((direction << 7 & LIBUSB_ENDPOINT_DIR_MASK) | (number & LIBUSB_ENDPOINT_ADDRESS_MASK));
-  }
-
-  cInterface->num_endpoints = numep;
-
-  return 0;
-}
-
-static int darwin_claim_interface(struct libusb_device_handle *dev_handle, int iface) {
-  struct darwin_device_priv *dpriv = (struct darwin_device_priv *)dev_handle->dev->os_priv;
-  struct darwin_device_handle_priv *priv = (struct darwin_device_handle_priv *)dev_handle->os_priv;
-  io_service_t          usbInterface = IO_OBJECT_NULL;
-  IOReturn kresult;
-  IOCFPlugInInterface **plugInInterface = NULL;
-  SInt32                score;
-
-  /* current interface */
-  struct darwin_interface *cInterface = &priv->interfaces[iface];
-
-  kresult = darwin_get_interface (dpriv->device, iface, &usbInterface);
-  if (kresult != kIOReturnSuccess)
-    return darwin_to_libusb (kresult);
-
-  /* make sure we have an interface */
-  if (!usbInterface && dpriv->first_config != 0) {
-    usbi_info (HANDLE_CTX (dev_handle), "no interface found; setting configuration: %d", dpriv->first_config);
-
-    /* set the configuration */
-    kresult = darwin_set_configuration (dev_handle, dpriv->first_config);
-    if (kresult != LIBUSB_SUCCESS) {
-      usbi_err (HANDLE_CTX (dev_handle), "could not set configuration");
-      return kresult;
-    }
-
-    kresult = darwin_get_interface (dpriv->device, iface, &usbInterface);
-    if (kresult) {
-      usbi_err (HANDLE_CTX (dev_handle), "darwin_get_interface: %s", darwin_error_str(kresult));
-      return darwin_to_libusb (kresult);
-    }
-  }
-
-  if (!usbInterface) {
-    usbi_err (HANDLE_CTX (dev_handle), "interface not found");
-    return LIBUSB_ERROR_NOT_FOUND;
-  }
-
-  /* get an interface to the device's interface */
-  kresult = IOCreatePlugInInterfaceForService (usbInterface, kIOUSBInterfaceUserClientTypeID,
-					       kIOCFPlugInInterfaceID, &plugInInterface, &score);
-
-  /* ignore release error */
-  (void)IOObjectRelease (usbInterface);
-
-  if (kresult) {
-    usbi_err (HANDLE_CTX (dev_handle), "IOCreatePlugInInterfaceForService: %s", darwin_error_str(kresult));
-    return darwin_to_libusb (kresult);
-  }
-
-  if (!plugInInterface) {
-    usbi_err (HANDLE_CTX (dev_handle), "plugin interface not found");
-    return LIBUSB_ERROR_NOT_FOUND;
-  }
-
-  /* Do the actual claim */
-  kresult = (*plugInInterface)->QueryInterface(plugInInterface,
-					       CFUUIDGetUUIDBytes(kIOUSBInterfaceInterfaceID),
-					       (LPVOID)&cInterface->interface);
-  /* We no longer need the intermediate plug-in */
-  IODestroyPlugInInterface (plugInInterface);
-  if (kresult || !cInterface->interface) {
-    usbi_err (HANDLE_CTX (dev_handle), "QueryInterface: %s", darwin_error_str(kresult));
-    return darwin_to_libusb (kresult);
-  }
-
-  /* claim the interface */
-  kresult = (*(cInterface->interface))->USBInterfaceOpen(cInterface->interface);
-  if (kresult) {
-    usbi_err (HANDLE_CTX (dev_handle), "USBInterfaceOpen: %s", darwin_error_str(kresult));
-    return darwin_to_libusb (kresult);
-  }
-
-  /* update list of endpoints */
-  kresult = get_endpoints (dev_handle, iface);
-  if (kresult) {
-    /* this should not happen */
-    darwin_release_interface (dev_handle, iface);
-    usbi_err (HANDLE_CTX (dev_handle), "could not build endpoint table");
-    return kresult;
-  }
-
-  cInterface->cfSource = NULL;
-
-  /* create async event source */
-  kresult = (*(cInterface->interface))->CreateInterfaceAsyncEventSource (cInterface->interface, &cInterface->cfSource);
-  if (kresult != kIOReturnSuccess) {
-    usbi_err (HANDLE_CTX (dev_handle), "could not create async event source");
-
-    /* can't continue without an async event source */
-    (void)darwin_release_interface (dev_handle, iface);
-
-    return darwin_to_libusb (kresult);
-  }
-
-  /* add the cfSource to the async thread's run loop */
-  CFRunLoopAddSource(libusb_darwin_acfl, cInterface->cfSource, kCFRunLoopDefaultMode);
-
-  usbi_info (HANDLE_CTX (dev_handle), "interface opened");
-
-  return 0;
-}
-
-static int darwin_release_interface(struct libusb_device_handle *dev_handle, int iface) {
-  struct darwin_device_handle_priv *priv = (struct darwin_device_handle_priv *)dev_handle->os_priv;
-  IOReturn kresult;
-
-  /* current interface */
-  struct darwin_interface *cInterface = &priv->interfaces[iface];
-
-  /* Check to see if an interface is open */
-  if (!cInterface->interface)
-    return LIBUSB_SUCCESS;
-
-  /* clean up endpoint data */
-  cInterface->num_endpoints = 0;
-
-  /* delete the interface's async event source */
-  if (cInterface->cfSource) {
-    CFRunLoopRemoveSource (libusb_darwin_acfl, cInterface->cfSource, kCFRunLoopDefaultMode);
-    CFRelease (cInterface->cfSource);
-  }
-
-  kresult = (*(cInterface->interface))->USBInterfaceClose(cInterface->interface);
-  if (kresult)
-    usbi_err (HANDLE_CTX (dev_handle), "USBInterfaceClose: %s", darwin_error_str(kresult));
-
-  kresult = (*(cInterface->interface))->Release(cInterface->interface);
-  if (kresult != kIOReturnSuccess)
-    usbi_err (HANDLE_CTX (dev_handle), "Release: %s", darwin_error_str(kresult));
-
-  cInterface->interface = IO_OBJECT_NULL;
-
-  return darwin_to_libusb (kresult);
-}
-
-static int darwin_set_interface_altsetting(struct libusb_device_handle *dev_handle, int iface, int altsetting) {
-  struct darwin_device_handle_priv *priv = (struct darwin_device_handle_priv *)dev_handle->os_priv;
-  IOReturn kresult;
-
-  /* current interface */
-  struct darwin_interface *cInterface = &priv->interfaces[iface];
-
-  if (!cInterface->interface)
-    return LIBUSB_ERROR_NO_DEVICE;
-
-  kresult = (*(cInterface->interface))->SetAlternateInterface (cInterface->interface, altsetting);
-  if (kresult != kIOReturnSuccess)
-    darwin_reset_device (dev_handle);
-
-  /* update list of endpoints */
-  kresult = get_endpoints (dev_handle, iface);
-  if (kresult) {
-    /* this should not happen */
-    darwin_release_interface (dev_handle, iface);
-    usbi_err (HANDLE_CTX (dev_handle), "could not build endpoint table");
-    return kresult;
-  }
-
-  return darwin_to_libusb (kresult);
-}
-
-static int darwin_clear_halt(struct libusb_device_handle *dev_handle, unsigned char endpoint) {
-  struct darwin_device_handle_priv *priv = (struct darwin_device_handle_priv *)dev_handle->os_priv;
-
-  /* current interface */
-  struct darwin_interface *cInterface;
-  uint8_t pipeRef, iface;
-  IOReturn kresult;
-
-  /* determine the interface/endpoint to use */
-  if (ep_to_pipeRef (dev_handle, endpoint, &pipeRef, &iface) != 0) {
-    usbi_err (HANDLE_CTX (dev_handle), "endpoint not found on any open interface");
-
-    return LIBUSB_ERROR_NOT_FOUND;
-  }
-
-  cInterface = &priv->interfaces[iface];
-
-#if (InterfaceVersion < 190)
-  kresult = (*(cInterface->interface))->ClearPipeStall(cInterface->interface, pipeRef);
-#else
-  /* newer versions of darwin support clearing additional bits on the device's endpoint */
-  kresult = (*(cInterface->interface))->ClearPipeStallBothEnds(cInterface->interface, pipeRef);
-#endif
-  if (kresult)
-    usbi_err (HANDLE_CTX (dev_handle), "ClearPipeStall: %s", darwin_error_str (kresult));
-
-  return darwin_to_libusb (kresult);
-}
-
-static int darwin_reset_device(struct libusb_device_handle *dev_handle) {
-  struct darwin_device_priv *dpriv = (struct darwin_device_priv *)dev_handle->dev->os_priv;
-  IOReturn kresult;
-
-  kresult = (*(dpriv->device))->ResetDevice (dpriv->device);
-  if (kresult)
-    usbi_err (HANDLE_CTX (dev_handle), "ResetDevice: %s", darwin_error_str (kresult));
-
-  return darwin_to_libusb (kresult);
-}
-
-static int darwin_kernel_driver_active(struct libusb_device_handle *dev_handle, int interface) {
-  struct darwin_device_priv *dpriv = (struct darwin_device_priv *)dev_handle->dev->os_priv;
-  io_service_t usbInterface;
-  CFTypeRef driver;
-  IOReturn kresult;
-
-  kresult = darwin_get_interface (dpriv->device, interface, &usbInterface);
-  if (kresult) {
-    usbi_err (HANDLE_CTX (dev_handle), "darwin_get_interface: %s", darwin_error_str(kresult));
-
-    return darwin_to_libusb (kresult);
-  }
-
-  driver = IORegistryEntryCreateCFProperty (usbInterface, kIOBundleIdentifierKey, kCFAllocatorDefault, 0);
-  IOObjectRelease (usbInterface);
-
-  if (driver) {
-    CFRelease (driver);
-
-    return 1;
-  }
-
-  /* no driver */
-  return 0;
-}
-
-/* attaching/detaching kernel drivers is not currently supported (maybe in the future?) */
-static int darwin_attach_kernel_driver (struct libusb_device_handle *dev_handle, int interface) {
-  (void)dev_handle;
-  (void)interface;
-  return LIBUSB_ERROR_NOT_SUPPORTED;
-}
-
-static int darwin_detach_kernel_driver (struct libusb_device_handle *dev_handle, int interface) {
-  (void)dev_handle;
-  (void)interface;
-  return LIBUSB_ERROR_NOT_SUPPORTED;
-}
-
-static void darwin_destroy_device(struct libusb_device *dev) {
-  (void)dev;
-}
-
-static int submit_bulk_transfer(struct usbi_transfer *itransfer) {
-  struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-  struct darwin_device_handle_priv *priv = (struct darwin_device_handle_priv *)transfer->dev_handle->os_priv;
-
-  IOReturn               ret;
-  uint8_t                is_read; /* 0 = we're reading, 1 = we're writing */
-  uint8_t                transferType;
-  /* None of the values below are used in libusb for bulk transfers */
-  uint8_t                direction, number, interval, pipeRef, iface;
-  uint16_t               maxPacketSize;
-
-  struct darwin_interface *cInterface;
-
-  /* are we reading or writing? */
-  is_read = transfer->endpoint & LIBUSB_ENDPOINT_IN;
-
-  if (ep_to_pipeRef (transfer->dev_handle, transfer->endpoint, &pipeRef, &iface) != 0) {
-    usbi_err (TRANSFER_CTX (transfer), "endpoint not found on any open interface");
-
-    return LIBUSB_ERROR_NOT_FOUND;
-  }
-
-  cInterface = &priv->interfaces[iface];
-
-  (*(cInterface->interface))->GetPipeProperties (cInterface->interface, pipeRef, &direction, &number,
-						 &transferType, &maxPacketSize, &interval);
-
-  /* submit the request */
-  /* timeouts are unavailable on interrupt endpoints */
-  if (transferType == kUSBInterrupt) {
-    if (is_read)
-      ret = (*(cInterface->interface))->ReadPipeAsync(cInterface->interface, pipeRef, transfer->buffer,
-						      transfer->length, darwin_async_io_callback, itransfer);
-    else
-      ret = (*(cInterface->interface))->WritePipeAsync(cInterface->interface, pipeRef, transfer->buffer,
-						       transfer->length, darwin_async_io_callback, itransfer);
-  } else {
-    itransfer->flags |= USBI_TRANSFER_OS_HANDLES_TIMEOUT;
-
-    if (is_read)
-      ret = (*(cInterface->interface))->ReadPipeAsyncTO(cInterface->interface, pipeRef, transfer->buffer,
-							transfer->length, transfer->timeout, transfer->timeout,
-							darwin_async_io_callback, (void *)itransfer);
-    else
-      ret = (*(cInterface->interface))->WritePipeAsyncTO(cInterface->interface, pipeRef, transfer->buffer,
-							 transfer->length, transfer->timeout, transfer->timeout,
-							 darwin_async_io_callback, (void *)itransfer);
-  }
-
-  if (ret)
-    usbi_err (TRANSFER_CTX (transfer), "bulk transfer failed (dir = %s): %s (code = 0x%08x)", is_read ? "In" : "Out",
-	       darwin_error_str(ret), ret);
-
-  return darwin_to_libusb (ret);
-}
-
-static int submit_iso_transfer(struct usbi_transfer *itransfer) {
-  struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-  struct darwin_transfer_priv *tpriv = usbi_transfer_get_os_priv(itransfer);
-  struct darwin_device_handle_priv *priv = (struct darwin_device_handle_priv *)transfer->dev_handle->os_priv;
-
-  IOReturn                kresult;
-  uint8_t                 is_read; /* 0 = we're writing, 1 = we're reading */
-  uint8_t                 pipeRef, iface;
-  UInt64                  frame;
-  AbsoluteTime            atTime;
-  int                     i;
-
-  struct darwin_interface *cInterface;
-
-  /* are we reading or writing? */
-  is_read = transfer->endpoint & LIBUSB_ENDPOINT_IN;
-
-  /* construct an array of IOUSBIsocFrames, reuse the old one if possible */
-  if (tpriv->isoc_framelist && tpriv->num_iso_packets != transfer->num_iso_packets) {
-    free(tpriv->isoc_framelist);
-    tpriv->isoc_framelist = NULL;
-  }
-
-  if (!tpriv->isoc_framelist) {
-    tpriv->num_iso_packets = transfer->num_iso_packets;
-    tpriv->isoc_framelist = (IOUSBIsocFrame*) calloc (transfer->num_iso_packets, sizeof(IOUSBIsocFrame));
-    if (!tpriv->isoc_framelist)
-      return LIBUSB_ERROR_NO_MEM;
-  }
-
-  /* copy the frame list from the libusb descriptor (the structures differ only is member order) */
-  for (i = 0 ; i < transfer->num_iso_packets ; i++)
-    tpriv->isoc_framelist[i].frReqCount = transfer->iso_packet_desc[i].length;
-
-  /* determine the interface/endpoint to use */
-  if (ep_to_pipeRef (transfer->dev_handle, transfer->endpoint, &pipeRef, &iface) != 0) {
-    usbi_err (TRANSFER_CTX (transfer), "endpoint not found on any open interface");
-
-    return LIBUSB_ERROR_NOT_FOUND;
-  }
-
-  cInterface = &priv->interfaces[iface];
-
-  /* Last but not least we need the bus frame number */
-  kresult = (*(cInterface->interface))->GetBusFrameNumber(cInterface->interface, &frame, &atTime);
-  if (kresult) {
-    usbi_err (TRANSFER_CTX (transfer), "failed to get bus frame number: %d", kresult);
-    free(tpriv->isoc_framelist);
-    tpriv->isoc_framelist = NULL;
-
-    return darwin_to_libusb (kresult);
-  }
-
-  /* schedule for a frame a little in the future */
-  frame += 4;
-
-  if (cInterface->frames[transfer->endpoint] && frame < cInterface->frames[transfer->endpoint])
-    frame = cInterface->frames[transfer->endpoint];
-
-  /* submit the request */
-  if (is_read)
-    kresult = (*(cInterface->interface))->ReadIsochPipeAsync(cInterface->interface, pipeRef, transfer->buffer, frame,
-							     transfer->num_iso_packets, tpriv->isoc_framelist, darwin_async_io_callback,
-							     itransfer);
-  else
-    kresult = (*(cInterface->interface))->WriteIsochPipeAsync(cInterface->interface, pipeRef, transfer->buffer, frame,
-							      transfer->num_iso_packets, tpriv->isoc_framelist, darwin_async_io_callback,
-							      itransfer);
-
-  cInterface->frames[transfer->endpoint] = frame + transfer->num_iso_packets / 8;
-
-  if (kresult != kIOReturnSuccess) {
-    usbi_err (TRANSFER_CTX (transfer), "isochronous transfer failed (dir: %s): %s", is_read ? "In" : "Out",
-	       darwin_error_str(kresult));
-    free (tpriv->isoc_framelist);
-    tpriv->isoc_framelist = NULL;
-  }
-
-  return darwin_to_libusb (kresult);
-}
-
-static int submit_control_transfer(struct usbi_transfer *itransfer) {
-  struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-  struct libusb_control_setup *setup = (struct libusb_control_setup *) transfer->buffer;
-  struct darwin_device_priv *dpriv = (struct darwin_device_priv *)transfer->dev_handle->dev->os_priv;
-  struct darwin_device_handle_priv *priv = (struct darwin_device_handle_priv *)transfer->dev_handle->os_priv;
-  struct darwin_transfer_priv *tpriv = usbi_transfer_get_os_priv(itransfer);
-
-  IOReturn               kresult;
-
-  bzero(&tpriv->req, sizeof(tpriv->req));
-
-  /* IOUSBDeviceInterface expects the request in cpu endianess */
-  tpriv->req.bmRequestType     = setup->bmRequestType;
-  tpriv->req.bRequest          = setup->bRequest;
-  /* these values should be in bus order from libusb_fill_control_setup */
-  tpriv->req.wValue            = OSSwapLittleToHostInt16 (setup->wValue);
-  tpriv->req.wIndex            = OSSwapLittleToHostInt16 (setup->wIndex);
-  tpriv->req.wLength           = OSSwapLittleToHostInt16 (setup->wLength);
-  /* data is stored after the libusb control block */
-  tpriv->req.pData             = transfer->buffer + LIBUSB_CONTROL_SETUP_SIZE;
-  tpriv->req.completionTimeout = transfer->timeout;
-  tpriv->req.noDataTimeout     = transfer->timeout;
-
-  itransfer->flags |= USBI_TRANSFER_OS_HANDLES_TIMEOUT;
-
-  /* all transfers in libusb-1.0 are async */
-
-  if (transfer->endpoint) {
-    struct darwin_interface *cInterface;
-    uint8_t                 pipeRef, iface;
-
-    if (ep_to_pipeRef (transfer->dev_handle, transfer->endpoint, &pipeRef, &iface) != 0) {
-      usbi_err (TRANSFER_CTX (transfer), "endpoint not found on any open interface");
-
-      return LIBUSB_ERROR_NOT_FOUND;
-    }
-
-    cInterface = &priv->interfaces[iface];
-
-    kresult = (*(cInterface->interface))->ControlRequestAsyncTO (cInterface->interface, pipeRef, &(tpriv->req), darwin_async_io_callback, itransfer);
-  } else
-    /* control request on endpoint 0 */
-    kresult = (*(dpriv->device))->DeviceRequestAsyncTO(dpriv->device, &(tpriv->req), darwin_async_io_callback, itransfer);
-
-  if (kresult != kIOReturnSuccess)
-    usbi_err (TRANSFER_CTX (transfer), "control request failed: %s", darwin_error_str(kresult));
-
-  return darwin_to_libusb (kresult);
-}
-
-static int darwin_submit_transfer(struct usbi_transfer *itransfer) {
-  struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-
-  switch (transfer->type) {
-  case LIBUSB_TRANSFER_TYPE_CONTROL:
-    return submit_control_transfer(itransfer);
-  case LIBUSB_TRANSFER_TYPE_BULK:
-  case LIBUSB_TRANSFER_TYPE_INTERRUPT:
-    return submit_bulk_transfer(itransfer);
-  case LIBUSB_TRANSFER_TYPE_ISOCHRONOUS:
-    return submit_iso_transfer(itransfer);
-  default:
-    usbi_err (TRANSFER_CTX(transfer), "unknown endpoint type %d", transfer->type);
-    return LIBUSB_ERROR_INVALID_PARAM;
-  }
-}
-
-static int cancel_control_transfer(struct usbi_transfer *itransfer) {
-  struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-  struct darwin_device_priv *dpriv = (struct darwin_device_priv *)transfer->dev_handle->dev->os_priv;
-  IOReturn kresult;
-
-  usbi_info (ITRANSFER_CTX (itransfer), "WARNING: aborting all transactions control pipe");
-
-  if (!dpriv->device)
-    return LIBUSB_ERROR_NO_DEVICE;
-
-  kresult = (*(dpriv->device))->USBDeviceAbortPipeZero (dpriv->device);
-
-  return darwin_to_libusb (kresult);
-}
-
-static int darwin_abort_transfers (struct usbi_transfer *itransfer) {
-  struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-  struct darwin_device_priv *dpriv = (struct darwin_device_priv *)transfer->dev_handle->dev->os_priv;
-  struct darwin_device_handle_priv *priv = (struct darwin_device_handle_priv *)transfer->dev_handle->os_priv;
-  struct darwin_interface *cInterface;
-  uint8_t pipeRef, iface;
-  IOReturn kresult;
-
-  if (ep_to_pipeRef (transfer->dev_handle, transfer->endpoint, &pipeRef, &iface) != 0) {
-    usbi_err (TRANSFER_CTX (transfer), "endpoint not found on any open interface");
-
-    return LIBUSB_ERROR_NOT_FOUND;
-  }
-
-  cInterface = &priv->interfaces[iface];
-
-  if (!dpriv->device)
-    return LIBUSB_ERROR_NO_DEVICE;
-
-  usbi_info (ITRANSFER_CTX (itransfer), "WARNING: aborting all transactions on interface %d pipe %d", iface, pipeRef);
-
-  /* abort transactions */
-  (*(cInterface->interface))->AbortPipe (cInterface->interface, pipeRef);
-
-  usbi_info (ITRANSFER_CTX (itransfer), "calling clear pipe stall to clear the data toggle bit");
-
-  /* clear the data toggle bit */
-#if (InterfaceVersion < 190)
-  kresult = (*(cInterface->interface))->ClearPipeStall(cInterface->interface, pipeRef);
-#else
-  /* newer versions of darwin support clearing additional bits on the device's endpoint */
-  kresult = (*(cInterface->interface))->ClearPipeStallBothEnds(cInterface->interface, pipeRef);
-#endif
-
-  return darwin_to_libusb (kresult);
-}
-
-static int darwin_cancel_transfer(struct usbi_transfer *itransfer) {
-  struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-
-  switch (transfer->type) {
-  case LIBUSB_TRANSFER_TYPE_CONTROL:
-    return cancel_control_transfer(itransfer);
-  case LIBUSB_TRANSFER_TYPE_BULK:
-  case LIBUSB_TRANSFER_TYPE_INTERRUPT:
-  case LIBUSB_TRANSFER_TYPE_ISOCHRONOUS:
-    return darwin_abort_transfers (itransfer);
-  default:
-    usbi_err (TRANSFER_CTX(transfer), "unknown endpoint type %d", transfer->type);
-    return LIBUSB_ERROR_INVALID_PARAM;
-  }
-}
-
-static void darwin_clear_transfer_priv (struct usbi_transfer *itransfer) {
-  struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-  struct darwin_transfer_priv *tpriv = usbi_transfer_get_os_priv(itransfer);
-
-  if (transfer->type == LIBUSB_TRANSFER_TYPE_ISOCHRONOUS && tpriv->isoc_framelist) {
-    free (tpriv->isoc_framelist);
-    tpriv->isoc_framelist = NULL;
-  }
-}
-
-static void darwin_async_io_callback (void *refcon, IOReturn result, void *arg0) {
-  struct usbi_transfer *itransfer = (struct usbi_transfer *)refcon;
-  struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-  struct darwin_device_handle_priv *priv = (struct darwin_device_handle_priv *)transfer->dev_handle->os_priv;
-  UInt32 message, size;
-
-  usbi_info (ITRANSFER_CTX (itransfer), "an async io operation has completed");
-
-  size = (UInt32) arg0;
-
-  /* send a completion message to the device's file descriptor */
-  message = MESSAGE_ASYNC_IO_COMPLETE;
-  write (priv->fds[1], &message, sizeof (message));
-  write (priv->fds[1], &itransfer, sizeof (itransfer));
-  write (priv->fds[1], &result, sizeof (IOReturn));
-  write (priv->fds[1], &size, sizeof (size));
-}
-
-static int darwin_transfer_status (struct usbi_transfer *itransfer, kern_return_t result) {
-  if (itransfer->flags & USBI_TRANSFER_TIMED_OUT)
-    result = kIOUSBTransactionTimeout;
-
-  switch (result) {
-  case kIOReturnUnderrun:
-  case kIOReturnSuccess:
-    return LIBUSB_TRANSFER_COMPLETED;
-  case kIOReturnAborted:
-    return LIBUSB_TRANSFER_CANCELLED;
-  case kIOUSBPipeStalled:
-    usbi_warn (ITRANSFER_CTX (itransfer), "transfer error: pipe is stalled");
-    return LIBUSB_TRANSFER_STALL;
-  case kIOReturnOverrun:
-    usbi_err (ITRANSFER_CTX (itransfer), "transfer error: data overrun");
-    return LIBUSB_TRANSFER_OVERFLOW;
-  case kIOUSBTransactionTimeout:
-    usbi_err (ITRANSFER_CTX (itransfer), "transfer error: timed out");
-    itransfer->flags |= USBI_TRANSFER_TIMED_OUT;
-    return LIBUSB_TRANSFER_TIMED_OUT;
-  default:
-    usbi_err (ITRANSFER_CTX (itransfer), "transfer error: %s (value = 0x%08x)", darwin_error_str (result), result);
-    return LIBUSB_TRANSFER_ERROR;
-  }
-}
-
-static void darwin_handle_callback (struct usbi_transfer *itransfer, kern_return_t result, UInt32 io_size) {
-  struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-  struct darwin_transfer_priv *tpriv = usbi_transfer_get_os_priv(itransfer);
-  int isIsoc      = LIBUSB_TRANSFER_TYPE_ISOCHRONOUS == transfer->type;
-  int isBulk      = LIBUSB_TRANSFER_TYPE_BULK == transfer->type;
-  int isControl   = LIBUSB_TRANSFER_TYPE_CONTROL == transfer->type;
-  int isInterrupt = LIBUSB_TRANSFER_TYPE_INTERRUPT == transfer->type;
-  int i;
-
-  if (!isIsoc && !isBulk && !isControl && !isInterrupt) {
-    usbi_err (TRANSFER_CTX(transfer), "unknown endpoint type %d", transfer->type);
-    return;
-  }
-
-  usbi_info (ITRANSFER_CTX (itransfer), "handling %s completion with kernel status %d",
-	     isControl ? "control" : isBulk ? "bulk" : isIsoc ? "isoc" : "interrupt", result);
-
-  if (kIOReturnSuccess == result || kIOReturnUnderrun == result) {
-    if (isIsoc && tpriv->isoc_framelist) {
-      /* copy isochronous results back */
-
-      for (i = 0; i < transfer->num_iso_packets ; i++) {
-	struct libusb_iso_packet_descriptor *lib_desc = &transfer->iso_packet_desc[i];
-	lib_desc->status = darwin_to_libusb (tpriv->isoc_framelist[i].frStatus);
-	lib_desc->actual_length = tpriv->isoc_framelist[i].frActCount;
-      }
-    } else if (!isIsoc)
-      itransfer->transferred += io_size;
-  }
-
-  /* it is ok to handle cancelled transfers without calling usbi_handle_transfer_cancellation (we catch timeout transfers) */
-  usbi_handle_transfer_completion (itransfer, darwin_transfer_status (itransfer, result));
-}
-
-static int op_handle_events(struct libusb_context *ctx, struct pollfd *fds, POLL_NFDS_TYPE nfds, int num_ready) {
-  struct usbi_transfer *itransfer;
-  UInt32 io_size;
-  IOReturn kresult;
-  POLL_NFDS_TYPE i = 0;
-  ssize_t ret;
-  UInt32 message;
-
-  usbi_mutex_lock(&ctx->open_devs_lock);
-  for (i = 0; i < nfds && num_ready > 0; i++) {
-    struct pollfd *pollfd = &fds[i];
-    struct libusb_device_handle *handle;
-    struct darwin_device_handle_priv *hpriv = NULL;
-
-    usbi_info (ctx, "checking fd %i with revents = %x", fds[i], pollfd->revents);
-
-    if (!pollfd->revents)
-      continue;
-
-    num_ready--;
-    list_for_each_entry(handle, &ctx->open_devs, list, struct libusb_device_handle) {
-      hpriv =  (struct darwin_device_handle_priv *)handle->os_priv;
-      if (hpriv->fds[0] == pollfd->fd)
-	break;
-    }
-
-    if (!(pollfd->revents & POLLERR)) {
-      ret = read (hpriv->fds[0], &message, sizeof (message));
-      if (ret < (ssize_t)sizeof (message))
-	continue;
-    } else
-      /* could not poll the device-- response is to delete the device (this seems a little heavy-handed) */
-      message = MESSAGE_DEVICE_GONE;
-
-    switch (message) {
-    case MESSAGE_DEVICE_GONE:
-      /* remove the device's async port from the runloop */
-      if (hpriv->cfSource) {
-	if (libusb_darwin_acfl)
-	  CFRunLoopRemoveSource (libusb_darwin_acfl, hpriv->cfSource, kCFRunLoopDefaultMode);
-	CFRelease (hpriv->cfSource);
-	hpriv->cfSource = NULL;
-      }
-
-      usbi_remove_pollfd(HANDLE_CTX(handle), hpriv->fds[0]);
-      usbi_handle_disconnect(handle);
-
-      /* done with this device */
-      continue;
-    case MESSAGE_ASYNC_IO_COMPLETE:
-      read (hpriv->fds[0], &itransfer, sizeof (itransfer));
-      read (hpriv->fds[0], &kresult, sizeof (IOReturn));
-      read (hpriv->fds[0], &io_size, sizeof (UInt32));
-
-      darwin_handle_callback (itransfer, kresult, io_size);
-      break;
-    default:
-      usbi_err (ctx, "unknown message received from device pipe");
-    }
-  }
-
-  usbi_mutex_unlock(&ctx->open_devs_lock);
-
-  return 0;
-}
-
-static int darwin_clock_gettime(int clk_id, struct timespec *tp) {
-  mach_timespec_t sys_time;
-  clock_serv_t clock_ref;
-
-  switch (clk_id) {
-  case USBI_CLOCK_REALTIME:
-    /* CLOCK_REALTIME represents time since the epoch */
-    clock_ref = clock_realtime;
-    break;
-  case USBI_CLOCK_MONOTONIC:
-    /* use system boot time as reference for the monotonic clock */
-    clock_ref = clock_monotonic;
-    break;
-  default:
-    return LIBUSB_ERROR_INVALID_PARAM;
-  }
-
-  clock_get_time (clock_ref, &sys_time);
-
-  tp->tv_sec  = sys_time.tv_sec;
-  tp->tv_nsec = sys_time.tv_nsec;
-
-  return 0;
-}
-
-const struct usbi_os_backend darwin_backend = {
-	.name = "Darwin",
-	.init = darwin_init,
-	.exit = darwin_exit,
-	.get_device_list = darwin_get_device_list,
-	.get_device_descriptor = darwin_get_device_descriptor,
-	.get_active_config_descriptor = darwin_get_active_config_descriptor,
-	.get_config_descriptor = darwin_get_config_descriptor,
-
-	.open = darwin_open,
-	.close = darwin_close,
-	.get_configuration = darwin_get_configuration,
-	.set_configuration = darwin_set_configuration,
-	.claim_interface = darwin_claim_interface,
-	.release_interface = darwin_release_interface,
-
-	.set_interface_altsetting = darwin_set_interface_altsetting,
-	.clear_halt = darwin_clear_halt,
-	.reset_device = darwin_reset_device,
-
-	.kernel_driver_active = darwin_kernel_driver_active,
-	.detach_kernel_driver = darwin_detach_kernel_driver,
-	.attach_kernel_driver = darwin_attach_kernel_driver,
-
-	.destroy_device = darwin_destroy_device,
-
-	.submit_transfer = darwin_submit_transfer,
-	.cancel_transfer = darwin_cancel_transfer,
-	.clear_transfer_priv = darwin_clear_transfer_priv,
-
-	.handle_events = op_handle_events,
-
-	.clock_gettime = darwin_clock_gettime,
-
-	.device_priv_size = sizeof(struct darwin_device_priv),
-	.device_handle_priv_size = sizeof(struct darwin_device_handle_priv),
-	.transfer_priv_size = sizeof(struct darwin_transfer_priv),
-	.add_iso_packet_size = 0,
-};
-
diff --git a/third_party/libusb/libusb/os/darwin_usb.h b/third_party/libusb/libusb/os/darwin_usb.h
deleted file mode 100644
index 59d0a69..0000000
--- a/third_party/libusb/libusb/os/darwin_usb.h
+++ /dev/null
@@ -1,169 +0,0 @@
-/*
- * darwin backend for libusb 1.0
- * Copyright (C) 2008-2009 Nathan Hjelm <hjelmn@users.sourceforge.net>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#if !defined(LIBUSB_DARWIN_H)
-#define LIBUSB_DARWIN_H
-
-#include "libusbi.h"
-
-#include <IOKit/IOTypes.h>
-#include <IOKit/IOCFBundle.h>
-#include <IOKit/usb/IOUSBLib.h>
-#include <IOKit/IOCFPlugIn.h>
-
-/* IOUSBInterfaceInferface */
-#if defined (kIOUSBInterfaceInterfaceID300)
-
-#define usb_interface_t IOUSBInterfaceInterface300
-#define InterfaceInterfaceID kIOUSBInterfaceInterfaceID300
-#define InterfaceVersion 300
-
-#elif defined (kIOUSBInterfaceInterfaceID245)
-
-#define usb_interface_t IOUSBInterfaceInterface245
-#define InterfaceInterfaceID kIOUSBInterfaceInterfaceID245
-#define InterfaceVersion 245
-
-#elif defined (kIOUSBInterfaceInterfaceID220)
-
-#define usb_interface_t IOUSBInterfaceInterface220
-#define InterfaceInterfaceID kIOUSBInterfaceInterfaceID220
-#define InterfaceVersion 220
-
-#elif defined (kIOUSBInterfaceInterfaceID197)
-
-#define usb_interface_t IOUSBInterfaceInterface197
-#define InterfaceInterfaceID kIOUSBInterfaceInterfaceID197
-#define InterfaceVersion 197
-
-#elif defined (kIOUSBInterfaceInterfaceID190)
-
-#define usb_interface_t IOUSBInterfaceInterface190
-#define InterfaceInterfaceID kIOUSBInterfaceInterfaceID190
-#define InterfaceVersion 190
-
-#elif defined (kIOUSBInterfaceInterfaceID182)
-
-#define usb_interface_t IOUSBInterfaceInterface182
-#define InterfaceInterfaceID kIOUSBInterfaceInterfaceID182
-#define InterfaceVersion 182
-
-#else
-
-#error "IOUSBFamily is too old. Please upgrade your OS"
-
-#endif
-
-/* IOUSBDeviceInterface */
-#if defined (kIOUSBDeviceInterfaceID320)
-
-#define usb_device_t    IOUSBDeviceInterface320
-#define DeviceInterfaceID kIOUSBDeviceInterfaceID320
-#define DeviceVersion 320
-
-#elif defined (kIOUSBDeviceInterfaceID300)
-
-#define usb_device_t    IOUSBDeviceInterface300
-#define DeviceInterfaceID kIOUSBDeviceInterfaceID300
-#define DeviceVersion 300
-
-#elif defined (kIOUSBDeviceInterfaceID245)
-
-#define usb_device_t    IOUSBDeviceInterface245
-#define DeviceInterfaceID kIOUSBDeviceInterfaceID245
-#define DeviceVersion 245
-
-#elif defined (kIOUSBDeviceInterfaceID197)
-
-#define usb_device_t    IOUSBDeviceInterface197
-#define DeviceInterfaceID kIOUSBDeviceInterfaceID197
-#define DeviceVersion 197
-
-#elif defined (kIOUSBDeviceInterfaceID187)
-
-#define usb_device_t    IOUSBDeviceInterface187
-#define DeviceInterfaceID kIOUSBDeviceInterfaceID187
-#define DeviceVersion 187
-
-#elif defined (kIOUSBDeviceInterfaceID182)
-
-#define usb_device_t    IOUSBDeviceInterface182
-#define DeviceInterfaceID kIOUSBDeviceInterfaceID182
-#define DeviceVersion 182
-
-#else
-
-#error "IOUSBFamily is too old. Please upgrade your OS"
-
-#endif
-
-#if !defined(IO_OBJECT_NULL)
-#define IO_OBJECT_NULL ((io_object_t) 0)
-#endif
-
-typedef IOCFPlugInInterface *io_cf_plugin_ref_t;
-typedef IONotificationPortRef io_notification_port_t;
-
-/* private structures */
-struct darwin_device_priv {
-  IOUSBDeviceDescriptor dev_descriptor;
-  UInt32                location;
-  char                  sys_path[21];
-  usb_device_t        **device;
-  int                   open_count;
-  UInt8                 first_config, active_config;
-};
-
-struct darwin_device_handle_priv {
-  int                  is_open;
-  CFRunLoopSourceRef   cfSource;
-  int                  fds[2];
-
-  struct darwin_interface {
-    usb_interface_t    **interface;
-    uint8_t              num_endpoints;
-    CFRunLoopSourceRef   cfSource;
-    uint64_t             frames[256];
-    uint8_t            endpoint_addrs[USB_MAXENDPOINTS];
-  } interfaces[USB_MAXINTERFACES];
-};
-
-struct darwin_transfer_priv {
-  /* Isoc */
-  IOUSBIsocFrame *isoc_framelist;
-  size_t num_iso_packets;
-
-  /* Control */
-#if !defined (LIBUSB_NO_TIMEOUT_DEVICE)
-  IOUSBDevRequestTO req;
-#else
-  IOUSBDevRequest req;
-#endif
-
-  /* Bulk */
-};
-
-enum {
-  MESSAGE_DEVICE_GONE,
-  MESSAGE_ASYNC_IO_COMPLETE
-};
-
-
-
-#endif
diff --git a/third_party/libusb/libusb/os/linux_usbfs.c b/third_party/libusb/libusb/os/linux_usbfs.c
deleted file mode 100644
index 2b81189..0000000
--- a/third_party/libusb/libusb/os/linux_usbfs.c
+++ /dev/null
@@ -1,2313 +0,0 @@
-/*
- * Linux usbfs backend for libusb
- * Copyright (C) 2007-2009 Daniel Drake <dsd@gentoo.org>
- * Copyright (c) 2001 Johannes Erdfelt <johannes@erdfelt.com>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#include <config.h>
-#include <ctype.h>
-#include <dirent.h>
-#include <errno.h>
-#include <fcntl.h>
-#include <poll.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/ioctl.h>
-#include <sys/stat.h>
-#include <sys/types.h>
-#include <sys/utsname.h>
-#include <unistd.h>
-
-#include "libusb.h"
-#include "libusbi.h"
-#include "linux_usbfs.h"
-
-/* sysfs vs usbfs:
- * opening a usbfs node causes the device to be resumed, so we attempt to
- * avoid this during enumeration.
- *
- * sysfs allows us to read the kernel's in-memory copies of device descriptors
- * and so forth, avoiding the need to open the device:
- *  - The binary "descriptors" file was added in 2.6.23.
- *  - The "busnum" file was added in 2.6.22
- *  - The "devnum" file has been present since pre-2.6.18
- *  - the "bConfigurationValue" file has been present since pre-2.6.18
- *
- * If we have bConfigurationValue, busnum, and devnum, then we can determine
- * the active configuration without having to open the usbfs node in RDWR mode.
- * We assume this is the case if we see the busnum file (indicates 2.6.22+).
- * The busnum file is important as that is the only way we can relate sysfs
- * devices to usbfs nodes.
- *
- * If we also have descriptors, we can obtain the device descriptor and active 
- * configuration without touching usbfs at all.
- *
- * The descriptors file originally only contained the active configuration
- * descriptor alongside the device descriptor, but all configurations are
- * included as of Linux 2.6.26.
- */
-
-/* endianness for multi-byte fields:
- *
- * Descriptors exposed by usbfs have the multi-byte fields in the device
- * descriptor as host endian. Multi-byte fields in the other descriptors are
- * bus-endian. The kernel documentation says otherwise, but it is wrong.
- */
-
-static const char *usbfs_path = NULL;
-
-/* Linux 2.6.32 adds support for a bulk continuation URB flag. this basically
- * allows us to mark URBs as being part of a specific logical transfer when
- * we submit them to the kernel. then, on any error except a cancellation, all
- * URBs within that transfer will be cancelled and no more URBs will be
- * accepted for the transfer, meaning that no more data can creep in.
- *
- * The BULK_CONTINUATION flag must be set on all URBs within a bulk transfer
- * (in either direction) except the first.
- * For IN transfers, we must also set SHORT_NOT_OK on all URBs except the
- * last; it means that the kernel should treat a short reply as an error.
- * For OUT transfers, SHORT_NOT_OK must not be set. it isn't needed (OUT
- * transfers can't be short unless there's already some sort of error), and
- * setting this flag is disallowed (a kernel with USB debugging enabled will
- * reject such URBs).
- */
-static int supports_flag_bulk_continuation = -1;
-
-/* clock ID for monotonic clock, as not all clock sources are available on all
- * systems. appropriate choice made at initialization time. */
-static clockid_t monotonic_clkid = -1;
-
-/* do we have a busnum to relate devices? this also implies that we can read
- * the active configuration through bConfigurationValue */
-static int sysfs_can_relate_devices = 0;
-
-/* do we have a descriptors file? */
-static int sysfs_has_descriptors = 0;
-
-struct linux_device_priv {
-	char *sysfs_dir;
-	unsigned char *dev_descriptor;
-	unsigned char *config_descriptor;
-};
-
-struct linux_device_handle_priv {
-	int fd;
-};
-
-enum reap_action {
-	NORMAL = 0,
-	/* submission failed after the first URB, so await cancellation/completion
-	 * of all the others */
-	SUBMIT_FAILED,
-
-	/* cancelled by user or timeout */
-	CANCELLED,
-
-	/* completed multi-URB transfer in non-final URB */
-	COMPLETED_EARLY,
-
-	/* one or more urbs encountered a low-level error */
-	ERROR,
-};
-
-struct linux_transfer_priv {
-	union {
-		struct usbfs_urb *urbs;
-		struct usbfs_urb **iso_urbs;
-	};
-
-	enum reap_action reap_action;
-	int num_urbs;
-	unsigned int num_retired;
-	enum libusb_transfer_status reap_status;
-
-	/* next iso packet in user-supplied transfer to be populated */
-	int iso_packet_offset;
-};
-
-static void _get_usbfs_path(struct libusb_device *dev, char *path)
-{
-	snprintf(path, PATH_MAX, "%s/%03d/%03d", usbfs_path, dev->bus_number,
-		dev->device_address);
-}
-
-static struct linux_device_priv *_device_priv(struct libusb_device *dev)
-{
-	return (struct linux_device_priv *) dev->os_priv;
-}
-
-static struct linux_device_handle_priv *_device_handle_priv(
-	struct libusb_device_handle *handle)
-{
-	return (struct linux_device_handle_priv *) handle->os_priv;
-}
-
-static int check_usb_vfs(const char *dirname)
-{
-	DIR *dir;
-	struct dirent *entry;
-	int found = 0;
-
-	dir = opendir(dirname);
-	if (!dir)
-		return 0;
-
-	while ((entry = readdir(dir)) != NULL) {
-		if (entry->d_name[0] == '.')
-			continue;
-
-		/* We assume if we find any files that it must be the right place */
-		found = 1;
-		break;
-	}
-
-	closedir(dir);
-	return found;
-}
-
-static const char *find_usbfs_path(void)
-{
-	const char *path = "/dev/bus/usb";
-	const char *ret = NULL;
-
-	if (check_usb_vfs(path)) {
-		ret = path;
-	} else {
-		path = "/proc/bus/usb";
-		if (check_usb_vfs(path))
-			ret = path;
-	}
-
-	usbi_dbg("found usbfs at %s", ret);
-	return ret;
-}
-
-/* the monotonic clock is not usable on all systems (e.g. embedded ones often
- * seem to lack it). fall back to REALTIME if we have to. */
-static clockid_t find_monotonic_clock(void)
-{
-	struct timespec ts;
-	int r;
-
-#ifdef CLOCK_MONOTONIC
-	/* Linux 2.6.28 adds CLOCK_MONOTONIC_RAW but we don't use it
-	 * because it's not available through timerfd */
-	r = clock_gettime(CLOCK_MONOTONIC, &ts);
-	if (r == 0)
-		return CLOCK_MONOTONIC;
-	usbi_dbg("monotonic clock doesn't work, errno %d", errno);
-#endif
-
-	return CLOCK_REALTIME;
-}
-
-/* bulk continuation URB flag available from Linux 2.6.32 */
-static int check_flag_bulk_continuation(void)
-{
-	struct utsname uts;
-	int atoms, major, minor, sublevel;
-
-	if (uname(&uts) < 0)
-		return -1;
-	atoms = sscanf(uts.release, "%d.%d.%d", &major, &minor, &sublevel);
-	if (atoms < 1)
-		return -1;
-
-	if (major > 2)
-		return 1;
-	if (major < 2)
-		return 0;
-
-	if (atoms < 2)
-		return 0;
-
-	/* major == 2 */
-	if (minor < 6)
-		return 0;
-	if (minor > 6) /* Does not exist, just here for correctness */
-		return 1;
-
-	/* 2.6.x */
-	if (3 == atoms && sublevel >= 32)
-		return 1;
-
-	return 0;
-}
-
-/* Return 1 if filename exists inside dirname in sysfs.
-   SYSFS_DEVICE_PATH is assumed to be the beginning of the path. */
-static int sysfs_has_file(const char *dirname, const char *filename)
-{
-	struct stat statbuf;
-	char path[PATH_MAX];
-	int r;
-
-	snprintf(path, PATH_MAX, "%s/%s/%s", SYSFS_DEVICE_PATH, dirname, filename);
-	r = stat(path, &statbuf);
-	if (r == 0 && S_ISREG(statbuf.st_mode))
-		return 1;
-
-	return 0;
-}
-
-static int op_init(struct libusb_context *ctx)
-{
-	struct stat statbuf;
-	int r;
-
-	usbfs_path = find_usbfs_path();
-	if (!usbfs_path) {
-		usbi_err(ctx, "could not find usbfs");
-		return LIBUSB_ERROR_OTHER;
-	}
-
-	if (monotonic_clkid == -1)
-		monotonic_clkid = find_monotonic_clock();
-
-	if (supports_flag_bulk_continuation == -1) {
-		supports_flag_bulk_continuation = check_flag_bulk_continuation();
-		if (supports_flag_bulk_continuation == -1) {
-			usbi_err(ctx, "error checking for bulk continuation support");
-			return LIBUSB_ERROR_OTHER;
-		}
-	}
-
-	if (supports_flag_bulk_continuation)
-		usbi_dbg("bulk continuation flag supported");
-
-	r = stat(SYSFS_DEVICE_PATH, &statbuf);
-	if (r == 0 && S_ISDIR(statbuf.st_mode)) {
-		DIR *devices = opendir(SYSFS_DEVICE_PATH);
-		struct dirent *entry;
-
-		usbi_dbg("found usb devices in sysfs");
-
-		if (!devices) {
-			usbi_err(ctx, "opendir devices failed errno=%d", errno);
-			return LIBUSB_ERROR_IO;
-		}
-
-		/* Make sure sysfs supports all the required files. If it
-		 * does not, then usbfs will be used instead.  Determine
-		 * this by looping through the directories in
-		 * SYSFS_DEVICE_PATH.  With the assumption that there will
-		 * always be subdirectories of the name usbN (usb1, usb2,
-		 * etc) representing the root hubs, check the usbN
-		 * subdirectories to see if they have all the needed files.
-		 * This algorithm uses the usbN subdirectories (root hubs)
-		 * because a device disconnection will cause a race
-		 * condition regarding which files are available, sometimes
-		 * causing an incorrect result.  The root hubs are used
-		 * because it is assumed that they will always be present.
-		 * See the "sysfs vs usbfs" comment at the top of this file
-		 * for more details.  */
-		while ((entry = readdir(devices))) {
-			int has_busnum=0, has_devnum=0, has_descriptors=0;
-			int has_configuration_value=0;
-
-			/* Only check the usbN directories. */
-			if (strncmp(entry->d_name, "usb", 3) != 0)
-				continue;
-
-			/* Check for the files libusb needs from sysfs. */
-			has_busnum = sysfs_has_file(entry->d_name, "busnum");
-			has_devnum = sysfs_has_file(entry->d_name, "devnum");
-			has_descriptors = sysfs_has_file(entry->d_name, "descriptors");
-			has_configuration_value = sysfs_has_file(entry->d_name, "bConfigurationValue");
-
-			if (has_busnum && has_devnum && has_configuration_value)
-				sysfs_can_relate_devices = 1;
-			if (has_descriptors)
-				sysfs_has_descriptors = 1;
-
-			/* Only need to check until we've found ONE device which
-			   has all the attributes. */
-			if (sysfs_has_descriptors && sysfs_can_relate_devices)
-				break;
-		}
-		closedir(devices);
-
-		/* Only use sysfs descriptors if the rest of
-		   sysfs will work for libusb. */
-		if (!sysfs_can_relate_devices)
-			sysfs_has_descriptors = 0;
-	} else {
-		usbi_dbg("sysfs usb info not available");
-		sysfs_has_descriptors = 0;
-		sysfs_can_relate_devices = 0;
-	}
-
-	return 0;
-}
-
-static int usbfs_get_device_descriptor(struct libusb_device *dev,
-	unsigned char *buffer)
-{
-	struct linux_device_priv *priv = _device_priv(dev);
-
-	/* return cached copy */
-	memcpy(buffer, priv->dev_descriptor, DEVICE_DESC_LENGTH);
-	return 0;
-}
-
-static int _open_sysfs_attr(struct libusb_device *dev, const char *attr)
-{
-	struct linux_device_priv *priv = _device_priv(dev);
-	char filename[PATH_MAX];
-	int fd;
-
-	snprintf(filename, PATH_MAX, "%s/%s/%s",
-		SYSFS_DEVICE_PATH, priv->sysfs_dir, attr);
-	fd = open(filename, O_RDONLY);
-	if (fd < 0) {
-		usbi_err(DEVICE_CTX(dev),
-			"open %s failed ret=%d errno=%d", filename, fd, errno);
-		return LIBUSB_ERROR_IO;
-	}
-
-	return fd;
-}
-
-/* Note only suitable for attributes which always read >= 0, < 0 is error */
-static int __read_sysfs_attr(struct libusb_context *ctx,
-	const char *devname, const char *attr)
-{
-	char filename[PATH_MAX];
-	FILE *f;
-	int r, value;
-
-	snprintf(filename, PATH_MAX, "%s/%s/%s", SYSFS_DEVICE_PATH,
-		 devname, attr);
-	f = fopen(filename, "r");
-	if (f == NULL) {
-		if (errno == ENOENT) {
-			/* File doesn't exist. Assume the device has been
-			   disconnected (see trac ticket #70). */
-			return LIBUSB_ERROR_NO_DEVICE;
-		}
-		usbi_err(ctx, "open %s failed errno=%d", filename, errno);
-		return LIBUSB_ERROR_IO;
-	}
-
-	r = fscanf(f, "%d", &value);
-	fclose(f);
-	if (r != 1) {
-		usbi_err(ctx, "fscanf %s returned %d, errno=%d", attr, r, errno);
-		return LIBUSB_ERROR_NO_DEVICE; /* For unplug race (trac #70) */
-	}
-	if (value < 0) {
-		usbi_err(ctx, "%s contains a negative value", filename);
-		return LIBUSB_ERROR_IO;
-	}
-
-	return value;
-}
-
-static int sysfs_get_device_descriptor(struct libusb_device *dev,
-	unsigned char *buffer)
-{
-	int fd;
-	ssize_t r;
-
-	/* sysfs provides access to an in-memory copy of the device descriptor,
-	 * so we use that rather than keeping our own copy */
-
-	fd = _open_sysfs_attr(dev, "descriptors");
-	if (fd < 0)
-		return fd;
-
-	r = read(fd, buffer, DEVICE_DESC_LENGTH);;
-	close(fd);
-	if (r < 0) {
-		usbi_err(DEVICE_CTX(dev), "read failed, ret=%d errno=%d", fd, errno);
-		return LIBUSB_ERROR_IO;
-	} else if (r < DEVICE_DESC_LENGTH) {
-		usbi_err(DEVICE_CTX(dev), "short read %d/%d", r, DEVICE_DESC_LENGTH);
-		return LIBUSB_ERROR_IO;
-	}
-
-	return 0;
-}
-
-static int op_get_device_descriptor(struct libusb_device *dev,
-	unsigned char *buffer, int *host_endian)
-{
-	if (sysfs_has_descriptors) {
-		return sysfs_get_device_descriptor(dev, buffer);
-	} else {
-		*host_endian = 1;
-		return usbfs_get_device_descriptor(dev, buffer);
-	}
-}
-
-static int usbfs_get_active_config_descriptor(struct libusb_device *dev,
-	unsigned char *buffer, size_t len)
-{
-	struct linux_device_priv *priv = _device_priv(dev);
-	if (!priv->config_descriptor)
-		return LIBUSB_ERROR_NOT_FOUND; /* device is unconfigured */
-
-	/* retrieve cached copy */
-	memcpy(buffer, priv->config_descriptor, len);
-	return 0;
-}
-
-/* read the bConfigurationValue for a device */
-static int sysfs_get_active_config(struct libusb_device *dev, int *config)
-{
-	char *endptr;
-	char tmp[4] = {0, 0, 0, 0};
-	long num;
-	int fd;
-	ssize_t r;
-
-	fd = _open_sysfs_attr(dev, "bConfigurationValue");
-	if (fd < 0)
-		return fd;
-
-	r = read(fd, tmp, sizeof(tmp));
-	close(fd);
-	if (r < 0) {
-		usbi_err(DEVICE_CTX(dev), 
-			"read bConfigurationValue failed ret=%d errno=%d", r, errno);
-		return LIBUSB_ERROR_IO;
-	} else if (r == 0) {
-		usbi_err(DEVICE_CTX(dev), "device unconfigured");
-		*config = -1;
-		return 0;
-	}
-
-	if (tmp[sizeof(tmp) - 1] != 0) {
-		usbi_err(DEVICE_CTX(dev), "not null-terminated?");
-		return LIBUSB_ERROR_IO;
-	} else if (tmp[0] == 0) {
-		usbi_err(DEVICE_CTX(dev), "no configuration value?");
-		return LIBUSB_ERROR_IO;
-	}
-
-	num = strtol(tmp, &endptr, 10);
-	if (endptr == tmp) {
-		usbi_err(DEVICE_CTX(dev), "error converting '%s' to integer", tmp);
-		return LIBUSB_ERROR_IO;
-	}
-
-	*config = (int) num;
-	return 0;
-}
-
-/* takes a usbfs/descriptors fd seeked to the start of a configuration, and
- * seeks to the next one. */
-static int seek_to_next_config(struct libusb_context *ctx, int fd,
-	int host_endian)
-{
-	struct libusb_config_descriptor config;
-	unsigned char tmp[6];
-	off_t off;
-	ssize_t r;
-
-	/* read first 6 bytes of descriptor */
-	r = read(fd, tmp, sizeof(tmp));
-	if (r < 0) {
-		usbi_err(ctx, "read failed ret=%d errno=%d", r, errno);
-		return LIBUSB_ERROR_IO;
-	} else if (r < sizeof(tmp)) {
-		usbi_err(ctx, "short descriptor read %d/%d", r, sizeof(tmp));
-		return LIBUSB_ERROR_IO;
-	}
-
-	/* seek forward to end of config */
-	usbi_parse_descriptor(tmp, "bbwbb", &config, host_endian);
-	off = lseek(fd, config.wTotalLength - sizeof(tmp), SEEK_CUR);
-	if (off < 0) {
-		usbi_err(ctx, "seek failed ret=%d errno=%d", off, errno);
-		return LIBUSB_ERROR_IO;
-	}
-
-	return 0;
-}
-
-static int sysfs_get_active_config_descriptor(struct libusb_device *dev,
-	unsigned char *buffer, size_t len)
-{
-	int fd;
-	ssize_t r;
-	off_t off;
-	int to_copy;
-	int config;
-	unsigned char tmp[6];
-
-	r = sysfs_get_active_config(dev, &config);
-	if (r < 0)
-		return r;
-	if (config == -1)
-		return LIBUSB_ERROR_NOT_FOUND;
-
-	usbi_dbg("active configuration %d", config);
-
-	/* sysfs provides access to an in-memory copy of the device descriptor,
-	 * so we use that rather than keeping our own copy */
-
-	fd = _open_sysfs_attr(dev, "descriptors");
-	if (fd < 0)
-		return fd;
-
-	/* device might have been unconfigured since we read bConfigurationValue,
-	 * so first check that there is any config descriptor data at all... */
-	off = lseek(fd, 0, SEEK_END);
-	if (off < 1) {
-		usbi_err(DEVICE_CTX(dev), "end seek failed, ret=%d errno=%d",
-			off, errno);
-		close(fd);
-		return LIBUSB_ERROR_IO;
-	} else if (off == DEVICE_DESC_LENGTH) {
-		close(fd);
-		return LIBUSB_ERROR_NOT_FOUND;
-	}
-
-	off = lseek(fd, DEVICE_DESC_LENGTH, SEEK_SET);
-	if (off < 0) {
-		usbi_err(DEVICE_CTX(dev), "seek failed, ret=%d errno=%d", off, errno);
-		close(fd);
-		return LIBUSB_ERROR_IO;
-	}
-
-	/* unbounded loop: we expect the descriptor to be present under all
-	 * circumstances */
-	while (1) {
-		r = read(fd, tmp, sizeof(tmp));
-		if (r < 0) {
-			usbi_err(DEVICE_CTX(dev), "read failed, ret=%d errno=%d",
-				fd, errno);
-			return LIBUSB_ERROR_IO;
-		} else if (r < sizeof(tmp)) {
-			usbi_err(DEVICE_CTX(dev), "short read %d/%d", r, sizeof(tmp));
-			return LIBUSB_ERROR_IO;
-		}
-
-		/* check bConfigurationValue */
-		if (tmp[5] == config)
-			break;
-
-		/* try the next descriptor */
-		off = lseek(fd, 0 - sizeof(tmp), SEEK_CUR);
-		if (off < 0)
-			return LIBUSB_ERROR_IO;
-
-		r = seek_to_next_config(DEVICE_CTX(dev), fd, 0);
-		if (r < 0)
-			return r;
-	}
-
-	to_copy = (len < sizeof(tmp)) ? len : sizeof(tmp);
-	memcpy(buffer, tmp, to_copy);
-	if (len > sizeof(tmp)) {
-		r = read(fd, buffer + sizeof(tmp), len - sizeof(tmp));
-		if (r < 0) {
-			usbi_err(DEVICE_CTX(dev), "read failed, ret=%d errno=%d",
-				fd, errno);
-			r = LIBUSB_ERROR_IO;
-		} else if (r == 0) {
-			usbi_dbg("device is unconfigured");
-			r = LIBUSB_ERROR_NOT_FOUND;
-		} else if (r < len - sizeof(tmp)) {
-			usbi_err(DEVICE_CTX(dev), "short read %d/%d", r, len);
-			r = LIBUSB_ERROR_IO;
-		}
-	} else {
-		r = 0;
-	}
-
-	close(fd);
-	return r;
-}
-
-static int op_get_active_config_descriptor(struct libusb_device *dev,
-	unsigned char *buffer, size_t len, int *host_endian)
-{
-	if (sysfs_has_descriptors) {
-		return sysfs_get_active_config_descriptor(dev, buffer, len);
-	} else {
-		return usbfs_get_active_config_descriptor(dev, buffer, len);
-	}
-}
-
-/* takes a usbfs fd, attempts to find the requested config and copy a certain
- * amount of it into an output buffer. */
-static int get_config_descriptor(struct libusb_context *ctx, int fd,
-	uint8_t config_index, unsigned char *buffer, size_t len)
-{
-	off_t off;
-	ssize_t r;
-
-	off = lseek(fd, DEVICE_DESC_LENGTH, SEEK_SET);
-	if (off < 0) {
-		usbi_err(ctx, "seek failed ret=%d errno=%d", off, errno);
-		return LIBUSB_ERROR_IO;
-	}
-
-	/* might need to skip some configuration descriptors to reach the
-	 * requested configuration */
-	while (config_index > 0) {
-		r = seek_to_next_config(ctx, fd, 1);
-		if (r < 0)
-			return r;
-		config_index--;
-	}
-
-	/* read the rest of the descriptor */
-	r = read(fd, buffer, len);
-	if (r < 0) {
-		usbi_err(ctx, "read failed ret=%d errno=%d", r, errno);
-		return LIBUSB_ERROR_IO;
-	} else if (r < len) {
-		usbi_err(ctx, "short output read %d/%d", r, len);
-		return LIBUSB_ERROR_IO;
-	}
-
-	return 0;
-}
-
-static int op_get_config_descriptor(struct libusb_device *dev,
-	uint8_t config_index, unsigned char *buffer, size_t len, int *host_endian)
-{
-	char filename[PATH_MAX];
-	int fd;
-	int r;
-
-	/* always read from usbfs: sysfs only has the active descriptor
-	 * this will involve waking the device up, but oh well! */
-
-	/* FIXME: the above is no longer true, new kernels have all descriptors
-	 * in the descriptors file. but its kinda hard to detect if the kernel
-	 * is sufficiently new. */
-
-	_get_usbfs_path(dev, filename);
-	fd = open(filename, O_RDONLY);
-	if (fd < 0) {
-		usbi_err(DEVICE_CTX(dev),
-			"open '%s' failed, ret=%d errno=%d", filename, fd, errno);
-		return LIBUSB_ERROR_IO;
-	}
-
-	r = get_config_descriptor(DEVICE_CTX(dev), fd, config_index, buffer, len);
-	close(fd);
-	return r;
-}
-
-/* cache the active config descriptor in memory. a value of -1 means that
- * we aren't sure which one is active, so just assume the first one. 
- * only for usbfs. */
-static int cache_active_config(struct libusb_device *dev, int fd,
-	int active_config)
-{
-	struct linux_device_priv *priv = _device_priv(dev);
-	struct libusb_config_descriptor config;
-	unsigned char tmp[8];
-	unsigned char *buf;
-	int idx;
-	int r;
-
-	if (active_config == -1) {
-		idx = 0;
-	} else {
-		r = usbi_get_config_index_by_value(dev, active_config, &idx);
-		if (r < 0)
-			return r;
-		if (idx == -1)
-			return LIBUSB_ERROR_NOT_FOUND;
-	}
-
-	r = get_config_descriptor(DEVICE_CTX(dev), fd, idx, tmp, sizeof(tmp));
-	if (r < 0) {
-		usbi_err(DEVICE_CTX(dev), "first read error %d", r);
-		return r;
-	}
-
-	usbi_parse_descriptor(tmp, "bbw", &config, 0);
-	buf = malloc(config.wTotalLength);
-	if (!buf)
-		return LIBUSB_ERROR_NO_MEM;
-
-	r = get_config_descriptor(DEVICE_CTX(dev), fd, idx, buf,
-		config.wTotalLength);
-	if (r < 0) {
-		free(buf);
-		return r;
-	}
-
-	if (priv->config_descriptor)
-		free(priv->config_descriptor);
-	priv->config_descriptor = buf;
-	return 0;
-}
-
-/* send a control message to retrieve active configuration */
-static int usbfs_get_active_config(struct libusb_device *dev, int fd)
-{
-	unsigned char active_config = 0;
-	int r;
-
-	struct usbfs_ctrltransfer ctrl = {
-		.bmRequestType = LIBUSB_ENDPOINT_IN,
-		.bRequest = LIBUSB_REQUEST_GET_CONFIGURATION,
-		.wValue = 0,
-		.wIndex = 0,
-		.wLength = 1,
-		.timeout = 1000,
-		.data = &active_config
-	};
-
-	r = ioctl(fd, IOCTL_USBFS_CONTROL, &ctrl);
-	if (r < 0) {
-		if (errno == ENODEV)
-			return LIBUSB_ERROR_NO_DEVICE;
-
-		/* we hit this error path frequently with buggy devices :( */
-		usbi_warn(DEVICE_CTX(dev),
-			"get_configuration failed ret=%d errno=%d", r, errno);
-		return LIBUSB_ERROR_IO;
-	}
-
-	return active_config;
-}
-
-static int initialize_device(struct libusb_device *dev, uint8_t busnum,
-	uint8_t devaddr, const char *sysfs_dir)
-{
-	struct linux_device_priv *priv = _device_priv(dev);
-	unsigned char *dev_buf;
-	char path[PATH_MAX];
-	int fd, speed;
-	int active_config = 0;
-	int device_configured = 1;
-	ssize_t r;
-
-	dev->bus_number = busnum;
-	dev->device_address = devaddr;
-
-	if (sysfs_dir) {
-		priv->sysfs_dir = malloc(strlen(sysfs_dir) + 1);
-		if (!priv->sysfs_dir)
-			return LIBUSB_ERROR_NO_MEM;
-		strcpy(priv->sysfs_dir, sysfs_dir);
-
-		/* Note speed can contain 1.5, in this case __read_sysfs_attr
-		   will stop parsing at the '.' and return 1 */
-		speed = __read_sysfs_attr(DEVICE_CTX(dev), sysfs_dir, "speed");
-		if (speed >= 0) {
-			switch (speed) {
-			case     1: dev->speed = LIBUSB_SPEED_LOW; break;
-			case    12: dev->speed = LIBUSB_SPEED_FULL; break;
-			case   480: dev->speed = LIBUSB_SPEED_HIGH; break;
-			case  5000: dev->speed = LIBUSB_SPEED_SUPER; break;
-			default:
-				usbi_warn(DEVICE_CTX(dev), "Unknown device speed: %d Mbps", speed);
-			}
-		}
-	}
-
-	if (sysfs_has_descriptors)
-		return 0;
-
-	/* cache device descriptor in memory so that we can retrieve it later
-	 * without waking the device up (op_get_device_descriptor) */
-
-	priv->dev_descriptor = NULL;
-	priv->config_descriptor = NULL;
-
-	if (sysfs_can_relate_devices) {
-		int tmp = sysfs_get_active_config(dev, &active_config);
-		if (tmp < 0)
-			return tmp;
-		if (active_config == -1)
-			device_configured = 0;
-	}
-
-	_get_usbfs_path(dev, path);
-	fd = open(path, O_RDWR);
-	if (fd < 0 && errno == EACCES) {
-		fd = open(path, O_RDONLY);
-		/* if we only have read-only access to the device, we cannot
-		 * send a control message to determine the active config. just
-		 * assume the first one is active. */
-		active_config = -1;
-	}
-
-	if (fd < 0) {
-		usbi_err(DEVICE_CTX(dev), "open failed, ret=%d errno=%d", fd, errno);
-		return LIBUSB_ERROR_IO;
-	}
-
-	if (!sysfs_can_relate_devices) {
-		if (active_config == -1) {
-			/* if we only have read-only access to the device, we cannot
-			 * send a control message to determine the active config. just
-			 * assume the first one is active. */
-			usbi_warn(DEVICE_CTX(dev), "access to %s is read-only; cannot "
-				"determine active configuration descriptor", path);
-		} else {
-			active_config = usbfs_get_active_config(dev, fd);
-			if (active_config == LIBUSB_ERROR_IO) {
-				/* buggy devices sometimes fail to report their active config.
-				 * assume unconfigured and continue the probing */
-				usbi_warn(DEVICE_CTX(dev), "couldn't query active "
-					"configuration, assumung unconfigured");
-				device_configured = 0;
-			} else if (active_config < 0) {
-				close(fd);
-				return active_config;
-			} else if (active_config == 0) {
-				/* some buggy devices have a configuration 0, but we're
-				 * reaching into the corner of a corner case here, so let's
-				 * not support buggy devices in these circumstances.
-				 * stick to the specs: a configuration value of 0 means
-				 * unconfigured. */
-				usbi_dbg("active cfg 0? assuming unconfigured device");
-				device_configured = 0;
-			}
-		}
-	}
-
-	dev_buf = malloc(DEVICE_DESC_LENGTH);
-	if (!dev_buf) {
-		close(fd);
-		return LIBUSB_ERROR_NO_MEM;
-	}
-
-	r = read(fd, dev_buf, DEVICE_DESC_LENGTH);
-	if (r < 0) {
-		usbi_err(DEVICE_CTX(dev),
-			"read descriptor failed ret=%d errno=%d", fd, errno);
-		free(dev_buf);
-		close(fd);
-		return LIBUSB_ERROR_IO;
-	} else if (r < DEVICE_DESC_LENGTH) {
-		usbi_err(DEVICE_CTX(dev), "short descriptor read (%d)", r);
-		free(dev_buf);
-		close(fd);
-		return LIBUSB_ERROR_IO;
-	}
-
-	/* bit of a hack: set num_configurations now because cache_active_config()
-	 * calls usbi_get_config_index_by_value() which uses it */
-	dev->num_configurations = dev_buf[DEVICE_DESC_LENGTH - 1];
-
-	if (device_configured) {
-		r = cache_active_config(dev, fd, active_config);
-		if (r < 0) {
-			close(fd);
-			free(dev_buf);
-			return r;
-		}
-	}
-
-	close(fd);
-	priv->dev_descriptor = dev_buf;
-	return 0;
-}
-
-static int enumerate_device(struct libusb_context *ctx,
-	struct discovered_devs **_discdevs, uint8_t busnum, uint8_t devaddr,
-	const char *sysfs_dir)
-{
-	struct discovered_devs *discdevs;
-	unsigned long session_id;
-	int need_unref = 0;
-	struct libusb_device *dev;
-	int r = 0;
-
-	/* FIXME: session ID is not guaranteed unique as addresses can wrap and
-	 * will be reused. instead we should add a simple sysfs attribute with
-	 * a session ID. */
-	session_id = busnum << 8 | devaddr;
-	usbi_dbg("busnum %d devaddr %d session_id %ld", busnum, devaddr,
-		session_id);
-
-	dev = usbi_get_device_by_session_id(ctx, session_id);
-	if (dev) {
-		usbi_dbg("using existing device for %d/%d (session %ld)",
-			busnum, devaddr, session_id);
-	} else {
-		usbi_dbg("allocating new device for %d/%d (session %ld)",
-			busnum, devaddr, session_id);
-		dev = usbi_alloc_device(ctx, session_id);
-		if (!dev)
-			return LIBUSB_ERROR_NO_MEM;
-		need_unref = 1;
-		r = initialize_device(dev, busnum, devaddr, sysfs_dir);
-		if (r < 0)
-			goto out;
-		r = usbi_sanitize_device(dev);
-		if (r < 0)
-			goto out;
-	}
-
-	discdevs = discovered_devs_append(*_discdevs, dev);
-	if (!discdevs)
-		r = LIBUSB_ERROR_NO_MEM;
-	else
-		*_discdevs = discdevs;
-
-out:
-	if (need_unref)
-		libusb_unref_device(dev);
-	return r;
-}
-
-/* open a bus directory and adds all discovered devices to discdevs. on
- * failure (non-zero return) the pre-existing discdevs should be destroyed
- * (and devices freed). on success, the new discdevs pointer should be used
- * as it may have been moved. */
-static int usbfs_scan_busdir(struct libusb_context *ctx,
-	struct discovered_devs **_discdevs, uint8_t busnum)
-{
-	DIR *dir;
-	char dirpath[PATH_MAX];
-	struct dirent *entry;
-	struct discovered_devs *discdevs = *_discdevs;
-	int r = LIBUSB_ERROR_IO;
-
-	snprintf(dirpath, PATH_MAX, "%s/%03d", usbfs_path, busnum);
-	usbi_dbg("%s", dirpath);
-	dir = opendir(dirpath);
-	if (!dir) {
-		usbi_err(ctx, "opendir '%s' failed, errno=%d", dirpath, errno);
-		/* FIXME: should handle valid race conditions like hub unplugged
-		 * during directory iteration - this is not an error */
-		return r;
-	}
-
-	while ((entry = readdir(dir))) {
-		int devaddr;
-
-		if (entry->d_name[0] == '.')
-			continue;
-
-		devaddr = atoi(entry->d_name);
-		if (devaddr == 0) {
-			usbi_dbg("unknown dir entry %s", entry->d_name);
-			continue;
-		}
-
-		if (enumerate_device(ctx, &discdevs, busnum, (uint8_t) devaddr, NULL)) {
-			usbi_dbg("failed to enumerate dir entry %s", entry->d_name);
-			continue;
-		}
-
-		r = 0;
-	}
-
-	if (!r)
-		*_discdevs = discdevs;
-	closedir(dir);
-	return r;
-}
-
-static int usbfs_get_device_list(struct libusb_context *ctx,
-	struct discovered_devs **_discdevs)
-{
-	struct dirent *entry;
-	DIR *buses = opendir(usbfs_path);
-	struct discovered_devs *discdevs = *_discdevs;
-	int r = 0;
-
-	if (!buses) {
-		usbi_err(ctx, "opendir buses failed errno=%d", errno);
-		return LIBUSB_ERROR_IO;
-	}
-
-	while ((entry = readdir(buses))) {
-		struct discovered_devs *discdevs_new = discdevs;
-		int busnum;
-
-		if (entry->d_name[0] == '.')
-			continue;
-
-		busnum = atoi(entry->d_name);
-		if (busnum == 0) {
-			usbi_dbg("unknown dir entry %s", entry->d_name);
-			continue;
-		}
-
-		r = usbfs_scan_busdir(ctx, &discdevs_new, busnum);
-		if (r < 0)
-			goto out;
-		discdevs = discdevs_new;
-	}
-
-out:
-	closedir(buses);
-	*_discdevs = discdevs;
-	return r;
-
-}
-
-static int sysfs_scan_device(struct libusb_context *ctx,
-	struct discovered_devs **_discdevs, const char *devname)
-{
-	int busnum;
-	int devaddr;
-
-	usbi_dbg("scan %s", devname);
-
-	busnum = __read_sysfs_attr(ctx, devname, "busnum");
-	if (busnum < 0)
-		return busnum;
-
-	devaddr = __read_sysfs_attr(ctx, devname, "devnum");
-	if (devaddr < 0)
-		return devaddr;
-
-	usbi_dbg("bus=%d dev=%d", busnum, devaddr);
-	if (busnum > 255 || devaddr > 255)
-		return LIBUSB_ERROR_INVALID_PARAM;
-
-	return enumerate_device(ctx, _discdevs, busnum & 0xff, devaddr & 0xff,
-		devname);
-}
-
-static int sysfs_get_device_list(struct libusb_context *ctx,
-	struct discovered_devs **_discdevs)
-{
-	struct discovered_devs *discdevs = *_discdevs;
-	DIR *devices = opendir(SYSFS_DEVICE_PATH);
-	struct dirent *entry;
-	int r = LIBUSB_ERROR_IO;
-
-	if (!devices) {
-		usbi_err(ctx, "opendir devices failed errno=%d", errno);
-		return r;
-	}
-
-	while ((entry = readdir(devices))) {
-		struct discovered_devs *discdevs_new = discdevs;
-
-		if ((!isdigit(entry->d_name[0]) && strncmp(entry->d_name, "usb", 3))
-				|| strchr(entry->d_name, ':'))
-			continue;
-
-		if (sysfs_scan_device(ctx, &discdevs_new, entry->d_name)) {
-			usbi_dbg("failed to enumerate dir entry %s", entry->d_name);
-			continue;
-		}
-
-		r = 0;
-		discdevs = discdevs_new;
-	}
-
-	if (!r)
-		*_discdevs = discdevs;
-	closedir(devices);
-	return r;
-}
-
-static int op_get_device_list(struct libusb_context *ctx,
-	struct discovered_devs **_discdevs)
-{
-	/* we can retrieve device list and descriptors from sysfs or usbfs.
-	 * sysfs is preferable, because if we use usbfs we end up resuming
-	 * any autosuspended USB devices. however, sysfs is not available
-	 * everywhere, so we need a usbfs fallback too.
-	 *
-	 * as described in the "sysfs vs usbfs" comment at the top of this
-	 * file, sometimes we have sysfs but not enough information to
-	 * relate sysfs devices to usbfs nodes.  op_init() determines the
-	 * adequacy of sysfs and sets sysfs_can_relate_devices.
-	 */
-	if (sysfs_can_relate_devices != 0)
-		return sysfs_get_device_list(ctx, _discdevs);
-	else
-		return usbfs_get_device_list(ctx, _discdevs);
-}
-
-static int op_open(struct libusb_device_handle *handle)
-{
-	struct linux_device_handle_priv *hpriv = _device_handle_priv(handle);
-	char filename[PATH_MAX];
-
-	_get_usbfs_path(handle->dev, filename);
-	usbi_dbg("opening %s", filename);
-	hpriv->fd = open(filename, O_RDWR);
-	if (hpriv->fd < 0) {
-		if (errno == EACCES) {
-			usbi_err(HANDLE_CTX(handle), "libusb couldn't open USB device %s: "
-				"Permission denied.", filename);
-			usbi_err(HANDLE_CTX(handle),
-				"libusb requires write access to USB device nodes.");
-			return LIBUSB_ERROR_ACCESS;
-		} else if (errno == ENOENT) {
-			usbi_err(HANDLE_CTX(handle), "libusb couldn't open USB device %s: "
-				"No such file or directory.", filename);
-			return LIBUSB_ERROR_NO_DEVICE;
-		} else {
-			usbi_err(HANDLE_CTX(handle),
-				"open failed, code %d errno %d", hpriv->fd, errno);
-			return LIBUSB_ERROR_IO;
-		}
-	}
-
-	return usbi_add_pollfd(HANDLE_CTX(handle), hpriv->fd, POLLOUT);
-}
-
-static void op_close(struct libusb_device_handle *dev_handle)
-{
-	int fd = _device_handle_priv(dev_handle)->fd;
-	usbi_remove_pollfd(HANDLE_CTX(dev_handle), fd);
-	close(fd);
-}
-
-static int op_get_configuration(struct libusb_device_handle *handle,
-	int *config)
-{
-	int r;
-	if (sysfs_can_relate_devices != 1)
-		return LIBUSB_ERROR_NOT_SUPPORTED;
-
-	r = sysfs_get_active_config(handle->dev, config);
-	if (r < 0)
-		return r;
-
-	if (*config == -1)
-		*config = 0;
-
-	return 0;
-}
-
-static int op_set_configuration(struct libusb_device_handle *handle, int config)
-{
-	struct linux_device_priv *priv = _device_priv(handle->dev);
-	int fd = _device_handle_priv(handle)->fd;
-	int r = ioctl(fd, IOCTL_USBFS_SETCONFIG, &config);
-	if (r) {
-		if (errno == EINVAL)
-			return LIBUSB_ERROR_NOT_FOUND;
-		else if (errno == EBUSY)
-			return LIBUSB_ERROR_BUSY;
-		else if (errno == ENODEV)
-			return LIBUSB_ERROR_NO_DEVICE;
-
-		usbi_err(HANDLE_CTX(handle), "failed, error %d errno %d", r, errno);
-		return LIBUSB_ERROR_OTHER;
-	}
-
-	if (!sysfs_has_descriptors) {
-		/* update our cached active config descriptor */
-		if (config == -1) {
-			if (priv->config_descriptor) {
-				free(priv->config_descriptor);
-				priv->config_descriptor = NULL;
-			}
-		} else {
-			r = cache_active_config(handle->dev, fd, config);
-			if (r < 0)
-				usbi_warn(HANDLE_CTX(handle),
-					"failed to update cached config descriptor, error %d", r);
-		}
-	}
-
-	return 0;
-}
-
-static int op_claim_interface(struct libusb_device_handle *handle, int iface)
-{
-	int fd = _device_handle_priv(handle)->fd;
-	int r = ioctl(fd, IOCTL_USBFS_CLAIMINTF, &iface);
-	if (r) {
-		if (errno == ENOENT)
-			return LIBUSB_ERROR_NOT_FOUND;
-		else if (errno == EBUSY)
-			return LIBUSB_ERROR_BUSY;
-		else if (errno == ENODEV)
-			return LIBUSB_ERROR_NO_DEVICE;
-
-		usbi_err(HANDLE_CTX(handle),
-			"claim interface failed, error %d errno %d", r, errno);
-		return LIBUSB_ERROR_OTHER;
-	}
-	return 0;
-}
-
-static int op_release_interface(struct libusb_device_handle *handle, int iface)
-{
-	int fd = _device_handle_priv(handle)->fd;
-	int r = ioctl(fd, IOCTL_USBFS_RELEASEINTF, &iface);
-	if (r) {
-		if (errno == ENODEV)
-			return LIBUSB_ERROR_NO_DEVICE;
-
-		usbi_err(HANDLE_CTX(handle),
-			"release interface failed, error %d errno %d", r, errno);
-		return LIBUSB_ERROR_OTHER;
-	}
-	return 0;
-}
-
-static int op_set_interface(struct libusb_device_handle *handle, int iface,
-	int altsetting)
-{
-	int fd = _device_handle_priv(handle)->fd;
-	struct usbfs_setinterface setintf;
-	int r;
-
-	setintf.interface = iface;
-	setintf.altsetting = altsetting;
-	r = ioctl(fd, IOCTL_USBFS_SETINTF, &setintf);
-	if (r) {
-		if (errno == EINVAL)
-			return LIBUSB_ERROR_NOT_FOUND;
-		else if (errno == ENODEV)
-			return LIBUSB_ERROR_NO_DEVICE;
-
-		usbi_err(HANDLE_CTX(handle),
-			"setintf failed error %d errno %d", r, errno);
-		return LIBUSB_ERROR_OTHER;
-	}
-
-	return 0;
-}
-
-static int op_clear_halt(struct libusb_device_handle *handle,
-	unsigned char endpoint)
-{
-	int fd = _device_handle_priv(handle)->fd;
-	unsigned int _endpoint = endpoint;
-	int r = ioctl(fd, IOCTL_USBFS_CLEAR_HALT, &_endpoint);
-	if (r) {
-		if (errno == ENOENT)
-			return LIBUSB_ERROR_NOT_FOUND;
-		else if (errno == ENODEV)
-			return LIBUSB_ERROR_NO_DEVICE;
-
-		usbi_err(HANDLE_CTX(handle),
-			"clear_halt failed error %d errno %d", r, errno);
-		return LIBUSB_ERROR_OTHER;
-	}
-
-	return 0;
-}
-
-static int op_reset_device(struct libusb_device_handle *handle)
-{
-	int fd = _device_handle_priv(handle)->fd;
-	int i, r, ret = 0;
-
-	/* Doing a device reset will cause the usbfs driver to get unbound
-	   from any interfaces it is bound to. By voluntarily unbinding
-	   the usbfs driver ourself, we stop the kernel from rebinding
-	   the interface after reset (which would end up with the interface
-	   getting bound to the in kernel driver if any). */
-	for (i = 0; i < USB_MAXINTERFACES; i++) {
-		if (handle->claimed_interfaces & (1L << i)) {
-			op_release_interface(handle, i);
-		}
-	}
-
-	usbi_mutex_lock(&handle->lock);
-	r = ioctl(fd, IOCTL_USBFS_RESET, NULL);
-	if (r) {
-		if (errno == ENODEV) {
-			ret = LIBUSB_ERROR_NOT_FOUND;
-			goto out;
-		}
-
-		usbi_err(HANDLE_CTX(handle),
-			"reset failed error %d errno %d", r, errno);
-		ret = LIBUSB_ERROR_OTHER;
-		goto out;
-	}
-
-	/* And re-claim any interfaces which were claimed before the reset */
-	for (i = 0; i < USB_MAXINTERFACES; i++) {
-		if (handle->claimed_interfaces & (1L << i)) {
-			r = op_claim_interface(handle, i);
-			if (r) {
-				usbi_warn(HANDLE_CTX(handle),
-					"failed to re-claim interface %d after reset", i);
-				handle->claimed_interfaces &= ~(1L << i);
-			}
-		}
-	}
-out:
-	usbi_mutex_unlock(&handle->lock);
-	return ret;
-}
-
-static int op_kernel_driver_active(struct libusb_device_handle *handle,
-	int interface)
-{
-	int fd = _device_handle_priv(handle)->fd;
-	struct usbfs_getdriver getdrv;
-	int r;
-
-	getdrv.interface = interface;
-	r = ioctl(fd, IOCTL_USBFS_GETDRIVER, &getdrv);
-	if (r) {
-		if (errno == ENODATA)
-			return 0;
-		else if (errno == ENODEV)
-			return LIBUSB_ERROR_NO_DEVICE;
-
-		usbi_err(HANDLE_CTX(handle),
-			"get driver failed error %d errno %d", r, errno);
-		return LIBUSB_ERROR_OTHER;
-	}
-
-	return 1;
-}
-
-static int op_detach_kernel_driver(struct libusb_device_handle *handle,
-	int interface)
-{
-	int fd = _device_handle_priv(handle)->fd;
-	struct usbfs_ioctl command;
-	int r;
-
-	command.ifno = interface;
-	command.ioctl_code = IOCTL_USBFS_DISCONNECT;
-	command.data = NULL;
-
-	r = ioctl(fd, IOCTL_USBFS_IOCTL, &command);
-	if (r) {
-		if (errno == ENODATA)
-			return LIBUSB_ERROR_NOT_FOUND;
-		else if (errno == EINVAL)
-			return LIBUSB_ERROR_INVALID_PARAM;
-		else if (errno == ENODEV)
-			return LIBUSB_ERROR_NO_DEVICE;
-
-		usbi_err(HANDLE_CTX(handle),
-			"detach failed error %d errno %d", r, errno);
-		return LIBUSB_ERROR_OTHER;
-	}
-
-	return 0;
-}
-
-static int op_attach_kernel_driver(struct libusb_device_handle *handle,
-	int interface)
-{
-	int fd = _device_handle_priv(handle)->fd;
-	struct usbfs_ioctl command;
-	int r;
-
-	command.ifno = interface;
-	command.ioctl_code = IOCTL_USBFS_CONNECT;
-	command.data = NULL;
-
-	r = ioctl(fd, IOCTL_USBFS_IOCTL, &command);
-	if (r < 0) {
-		if (errno == ENODATA)
-			return LIBUSB_ERROR_NOT_FOUND;
-		else if (errno == EINVAL)
-			return LIBUSB_ERROR_INVALID_PARAM;
-		else if (errno == ENODEV)
-			return LIBUSB_ERROR_NO_DEVICE;
-		else if (errno == EBUSY)
-			return LIBUSB_ERROR_BUSY;
-
-		usbi_err(HANDLE_CTX(handle),
-			"attach failed error %d errno %d", r, errno);
-		return LIBUSB_ERROR_OTHER;
-	} else if (r == 0) {
-		return LIBUSB_ERROR_NOT_FOUND;
-	}
-
-	return 0;
-}
-
-static void op_destroy_device(struct libusb_device *dev)
-{
-	struct linux_device_priv *priv = _device_priv(dev);
-	if (!sysfs_has_descriptors) {
-		if (priv->dev_descriptor)
-			free(priv->dev_descriptor);
-		if (priv->config_descriptor)
-			free(priv->config_descriptor);
-	}
-	if (priv->sysfs_dir)
-		free(priv->sysfs_dir);
-}
-
-/* URBs are discarded in reverse order of submission to avoid races. */
-static int discard_urbs(struct usbi_transfer *itransfer, int first, int last_plus_one)
-{
-	struct libusb_transfer *transfer =
-		USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	struct linux_transfer_priv *tpriv =
-		usbi_transfer_get_os_priv(itransfer);
-	struct linux_device_handle_priv *dpriv =
-		_device_handle_priv(transfer->dev_handle);
-	int i, ret = 0;
-	struct usbfs_urb *urb;
-
-	for (i = last_plus_one - 1; i >= first; i--) {
-		if (LIBUSB_TRANSFER_TYPE_ISOCHRONOUS == transfer->type)
-			urb = tpriv->iso_urbs[i];
-		else
-			urb = &tpriv->urbs[i];
-
-		if (0 == ioctl(dpriv->fd, IOCTL_USBFS_DISCARDURB, urb))
-			continue;
-
-		if (EINVAL == errno) {
-			usbi_dbg("URB not found --> assuming ready to be reaped");
-			ret = LIBUSB_ERROR_NOT_FOUND;
-		} else if (ENODEV == errno) {
-			usbi_dbg("Device not found for URB --> assuming ready to be reaped");
-			ret = LIBUSB_ERROR_NO_DEVICE;
-		} else {
-			usbi_warn(TRANSFER_CTX(transfer),
-				"unrecognised discard errno %d", errno);
-			ret = LIBUSB_ERROR_OTHER;
-		}
-	}
-	return ret;
-}
-
-static void free_iso_urbs(struct linux_transfer_priv *tpriv)
-{
-	int i;
-	for (i = 0; i < tpriv->num_urbs; i++) {
-		struct usbfs_urb *urb = tpriv->iso_urbs[i];
-		if (!urb)
-			break;
-		free(urb);
-	}
-
-	free(tpriv->iso_urbs);
-	tpriv->iso_urbs = NULL;
-}
-
-static int submit_bulk_transfer(struct usbi_transfer *itransfer,
-	unsigned char urb_type)
-{
-	struct libusb_transfer *transfer =
-		USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	struct linux_transfer_priv *tpriv = usbi_transfer_get_os_priv(itransfer);
-	struct linux_device_handle_priv *dpriv =
-		_device_handle_priv(transfer->dev_handle);
-	struct usbfs_urb *urbs;
-	int is_out = (transfer->endpoint & LIBUSB_ENDPOINT_DIR_MASK)
-		== LIBUSB_ENDPOINT_OUT;
-	int r;
-	int i;
-	size_t alloc_size;
-
-	if (tpriv->urbs)
-		return LIBUSB_ERROR_BUSY;
-
-	/* usbfs places a 16kb limit on bulk URBs. we divide up larger requests
-	 * into smaller units to meet such restriction, then fire off all the
-	 * units at once. it would be simpler if we just fired one unit at a time,
-	 * but there is a big performance gain through doing it this way. */
-	int num_urbs = transfer->length / MAX_BULK_BUFFER_LENGTH;
-	int last_urb_partial = 0;
-
-	if (transfer->length == 0) {
-		num_urbs = 1;
-	} else if ((transfer->length % MAX_BULK_BUFFER_LENGTH) > 0) {
-		last_urb_partial = 1;
-		num_urbs++;
-	}
-	usbi_dbg("need %d urbs for new transfer with length %d", num_urbs,
-		transfer->length);
-	alloc_size = num_urbs * sizeof(struct usbfs_urb);
-	urbs = malloc(alloc_size);
-	if (!urbs)
-		return LIBUSB_ERROR_NO_MEM;
-	memset(urbs, 0, alloc_size);
-	tpriv->urbs = urbs;
-	tpriv->num_urbs = num_urbs;
-	tpriv->num_retired = 0;
-	tpriv->reap_action = NORMAL;
-	tpriv->reap_status = LIBUSB_TRANSFER_COMPLETED;
-
-	for (i = 0; i < num_urbs; i++) {
-		struct usbfs_urb *urb = &urbs[i];
-		urb->usercontext = itransfer;
-		urb->type = urb_type;
-		urb->endpoint = transfer->endpoint;
-		urb->buffer = transfer->buffer + (i * MAX_BULK_BUFFER_LENGTH);
-		if (supports_flag_bulk_continuation && !is_out)
-			urb->flags = USBFS_URB_SHORT_NOT_OK;
-		if (i == num_urbs - 1 && last_urb_partial)
-			urb->buffer_length = transfer->length % MAX_BULK_BUFFER_LENGTH;
-		else if (transfer->length == 0)
-			urb->buffer_length = 0;
-		else
-			urb->buffer_length = MAX_BULK_BUFFER_LENGTH;
-
-		if (i > 0 && supports_flag_bulk_continuation)
-			urb->flags |= USBFS_URB_BULK_CONTINUATION;
-
-		r = ioctl(dpriv->fd, IOCTL_USBFS_SUBMITURB, urb);
-		if (r < 0) {
-			if (errno == ENODEV) {
-				r = LIBUSB_ERROR_NO_DEVICE;
-			} else {
-				usbi_err(TRANSFER_CTX(transfer),
-					"submiturb failed error %d errno=%d", r, errno);
-				r = LIBUSB_ERROR_IO;
-			}
-	
-			/* if the first URB submission fails, we can simply free up and
-			 * return failure immediately. */
-			if (i == 0) {
-				usbi_dbg("first URB failed, easy peasy");
-				free(urbs);
-				tpriv->urbs = NULL;
-				return r;
-			}
-
-			/* if it's not the first URB that failed, the situation is a bit
-			 * tricky. we may need to discard all previous URBs. there are
-			 * complications:
-			 *  - discarding is asynchronous - discarded urbs will be reaped
-			 *    later. the user must not have freed the transfer when the
-			 *    discarded URBs are reaped, otherwise libusb will be using
-			 *    freed memory.
-			 *  - the earlier URBs may have completed successfully and we do
-			 *    not want to throw away any data.
-			 *  - this URB failing may be no error; EREMOTEIO means that
-			 *    this transfer simply didn't need all the URBs we submitted
-			 * so, we report that the transfer was submitted successfully and
-			 * in case of error we discard all previous URBs. later when
-			 * the final reap completes we can report error to the user,
-			 * or success if an earlier URB was completed successfully.
-			 */
-			tpriv->reap_action = EREMOTEIO == errno ? COMPLETED_EARLY : SUBMIT_FAILED;
-
-			/* The URBs we haven't submitted yet we count as already
-			 * retired. */
-			tpriv->num_retired += num_urbs - i;
-
-			/* If we completed short then don't try to discard. */
-			if (COMPLETED_EARLY == tpriv->reap_action)
-				return 0;
-
-			discard_urbs(itransfer, 0, i);
-
-			usbi_dbg("reporting successful submission but waiting for %d "
-				"discards before reporting error", i);
-			return 0;
-		}
-	}
-
-	return 0;
-}
-
-static int submit_iso_transfer(struct usbi_transfer *itransfer)
-{
-	struct libusb_transfer *transfer =
-		USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	struct linux_transfer_priv *tpriv = usbi_transfer_get_os_priv(itransfer);
-	struct linux_device_handle_priv *dpriv =
-		_device_handle_priv(transfer->dev_handle);
-	struct usbfs_urb **urbs;
-	size_t alloc_size;
-	int num_packets = transfer->num_iso_packets;
-	int i;
-	int this_urb_len = 0;
-	int num_urbs = 1;
-	int packet_offset = 0;
-	unsigned int packet_len;
-	unsigned char *urb_buffer = transfer->buffer;
-
-	if (tpriv->iso_urbs)
-		return LIBUSB_ERROR_BUSY;
-
-	/* usbfs places a 32kb limit on iso URBs. we divide up larger requests
-	 * into smaller units to meet such restriction, then fire off all the
-	 * units at once. it would be simpler if we just fired one unit at a time,
-	 * but there is a big performance gain through doing it this way. */
-
-	/* calculate how many URBs we need */
-	for (i = 0; i < num_packets; i++) {
-		int space_remaining = MAX_ISO_BUFFER_LENGTH - this_urb_len;
-		packet_len = transfer->iso_packet_desc[i].length;
-
-		if (packet_len > space_remaining) {
-			num_urbs++;
-			this_urb_len = packet_len;
-		} else {
-			this_urb_len += packet_len;
-		}
-	}
-	usbi_dbg("need %d 32k URBs for transfer", num_urbs);
-
-	alloc_size = num_urbs * sizeof(*urbs);
-	urbs = malloc(alloc_size);
-	if (!urbs)
-		return LIBUSB_ERROR_NO_MEM;
-	memset(urbs, 0, alloc_size);
-
-	tpriv->iso_urbs = urbs;
-	tpriv->num_urbs = num_urbs;
-	tpriv->num_retired = 0;
-	tpriv->reap_action = NORMAL;
-	tpriv->iso_packet_offset = 0;
-
-	/* allocate + initialize each URB with the correct number of packets */
-	for (i = 0; i < num_urbs; i++) {
-		struct usbfs_urb *urb;
-		int space_remaining_in_urb = MAX_ISO_BUFFER_LENGTH;
-		int urb_packet_offset = 0;
-		unsigned char *urb_buffer_orig = urb_buffer;
-		int j;
-		int k;
-
-		/* swallow up all the packets we can fit into this URB */
-		while (packet_offset < transfer->num_iso_packets) {
-			packet_len = transfer->iso_packet_desc[packet_offset].length;
-			if (packet_len <= space_remaining_in_urb) {
-				/* throw it in */
-				urb_packet_offset++;
-				packet_offset++;
-				space_remaining_in_urb -= packet_len;
-				urb_buffer += packet_len;
-			} else {
-				/* it can't fit, save it for the next URB */
-				break;
-			}
-		}
-
-		alloc_size = sizeof(*urb)
-			+ (urb_packet_offset * sizeof(struct usbfs_iso_packet_desc));
-		urb = malloc(alloc_size);
-		if (!urb) {
-			free_iso_urbs(tpriv);
-			return LIBUSB_ERROR_NO_MEM;
-		}
-		memset(urb, 0, alloc_size);
-		urbs[i] = urb;
-
-		/* populate packet lengths */
-		for (j = 0, k = packet_offset - urb_packet_offset;
-				k < packet_offset; k++, j++) {
-			packet_len = transfer->iso_packet_desc[k].length;
-			urb->iso_frame_desc[j].length = packet_len;
-		}
-
-		urb->usercontext = itransfer;
-		urb->type = USBFS_URB_TYPE_ISO;
-		/* FIXME: interface for non-ASAP data? */
-		urb->flags = USBFS_URB_ISO_ASAP;
-		urb->endpoint = transfer->endpoint;
-		urb->number_of_packets = urb_packet_offset;
-		urb->buffer = urb_buffer_orig;
-	}
-
-	/* submit URBs */
-	for (i = 0; i < num_urbs; i++) {
-		int r = ioctl(dpriv->fd, IOCTL_USBFS_SUBMITURB, urbs[i]);
-		if (r < 0) {
-			if (errno == ENODEV) {
-				r = LIBUSB_ERROR_NO_DEVICE;
-			} else {
-				usbi_err(TRANSFER_CTX(transfer),
-					"submiturb failed error %d errno=%d", r, errno);
-				r = LIBUSB_ERROR_IO;
-			}
-
-			/* if the first URB submission fails, we can simply free up and
-			 * return failure immediately. */
-			if (i == 0) {
-				usbi_dbg("first URB failed, easy peasy");
-				free_iso_urbs(tpriv);
-				return r;
-			}
-
-			/* if it's not the first URB that failed, the situation is a bit
-			 * tricky. we must discard all previous URBs. there are
-			 * complications:
-			 *  - discarding is asynchronous - discarded urbs will be reaped
-			 *    later. the user must not have freed the transfer when the
-			 *    discarded URBs are reaped, otherwise libusb will be using
-			 *    freed memory.
-			 *  - the earlier URBs may have completed successfully and we do
-			 *    not want to throw away any data.
-			 * so, in this case we discard all the previous URBs BUT we report
-			 * that the transfer was submitted successfully. then later when
-			 * the final discard completes we can report error to the user.
-			 */
-			tpriv->reap_action = SUBMIT_FAILED;
-
-			/* The URBs we haven't submitted yet we count as already
-			 * retired. */
-			tpriv->num_retired = num_urbs - i;
-			discard_urbs(itransfer, 0, i);
-
-			usbi_dbg("reporting successful submission but waiting for %d "
-				"discards before reporting error", i);
-			return 0;
-		}
-	}
-
-	return 0;
-}
-
-static int submit_control_transfer(struct usbi_transfer *itransfer)
-{
-	struct linux_transfer_priv *tpriv = usbi_transfer_get_os_priv(itransfer);
-	struct libusb_transfer *transfer =
-		USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	struct linux_device_handle_priv *dpriv =
-		_device_handle_priv(transfer->dev_handle);
-	struct usbfs_urb *urb;
-	int r;
-
-	if (tpriv->urbs)
-		return LIBUSB_ERROR_BUSY;
-
-	if (transfer->length - LIBUSB_CONTROL_SETUP_SIZE > MAX_CTRL_BUFFER_LENGTH)
-		return LIBUSB_ERROR_INVALID_PARAM;
-
-	urb = malloc(sizeof(struct usbfs_urb));
-	if (!urb)
-		return LIBUSB_ERROR_NO_MEM;
-	memset(urb, 0, sizeof(struct usbfs_urb));
-	tpriv->urbs = urb;
-	tpriv->num_urbs = 1;
-	tpriv->reap_action = NORMAL;
-
-	urb->usercontext = itransfer;
-	urb->type = USBFS_URB_TYPE_CONTROL;
-	urb->endpoint = transfer->endpoint;
-	urb->buffer = transfer->buffer;
-	urb->buffer_length = transfer->length;
-
-	r = ioctl(dpriv->fd, IOCTL_USBFS_SUBMITURB, urb);
-	if (r < 0) {
-		free(urb);
-		tpriv->urbs = NULL;
-		if (errno == ENODEV)
-			return LIBUSB_ERROR_NO_DEVICE;
-
-		usbi_err(TRANSFER_CTX(transfer),
-			"submiturb failed error %d errno=%d", r, errno);
-		return LIBUSB_ERROR_IO;
-	}
-	return 0;
-}
-
-static int op_submit_transfer(struct usbi_transfer *itransfer)
-{
-	struct libusb_transfer *transfer =
-		USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-
-	switch (transfer->type) {
-	case LIBUSB_TRANSFER_TYPE_CONTROL:
-		return submit_control_transfer(itransfer);
-	case LIBUSB_TRANSFER_TYPE_BULK:
-		return submit_bulk_transfer(itransfer, USBFS_URB_TYPE_BULK);
-	case LIBUSB_TRANSFER_TYPE_INTERRUPT:
-		return submit_bulk_transfer(itransfer, USBFS_URB_TYPE_INTERRUPT);
-	case LIBUSB_TRANSFER_TYPE_ISOCHRONOUS:
-		return submit_iso_transfer(itransfer);
-	default:
-		usbi_err(TRANSFER_CTX(transfer),
-			"unknown endpoint type %d", transfer->type);
-		return LIBUSB_ERROR_INVALID_PARAM;
-	}
-}
-
-static int op_cancel_transfer(struct usbi_transfer *itransfer)
-{
-	struct linux_transfer_priv *tpriv = usbi_transfer_get_os_priv(itransfer);
-	struct libusb_transfer *transfer =
-		USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-
-	switch (transfer->type) {
-	case LIBUSB_TRANSFER_TYPE_BULK:
-		if (tpriv->reap_action == ERROR)
-			break;
-		/* else, fall through */
-	case LIBUSB_TRANSFER_TYPE_CONTROL:
-	case LIBUSB_TRANSFER_TYPE_INTERRUPT:
-	case LIBUSB_TRANSFER_TYPE_ISOCHRONOUS:
-		tpriv->reap_action = CANCELLED;
-		break;
-	default:
-		usbi_err(TRANSFER_CTX(transfer),
-			"unknown endpoint type %d", transfer->type);
-		return LIBUSB_ERROR_INVALID_PARAM;
-	}
-
-	if (!tpriv->urbs)
-		return LIBUSB_ERROR_NOT_FOUND;
-
-	return discard_urbs(itransfer, 0, tpriv->num_urbs);
-}
-
-static void op_clear_transfer_priv(struct usbi_transfer *itransfer)
-{
-	struct libusb_transfer *transfer =
-		USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	struct linux_transfer_priv *tpriv = usbi_transfer_get_os_priv(itransfer);
-
-	/* urbs can be freed also in submit_transfer so lock mutex first */
-	switch (transfer->type) {
-	case LIBUSB_TRANSFER_TYPE_CONTROL:
-	case LIBUSB_TRANSFER_TYPE_BULK:
-	case LIBUSB_TRANSFER_TYPE_INTERRUPT:
-		usbi_mutex_lock(&itransfer->lock);
-		if (tpriv->urbs)
-			free(tpriv->urbs);
-		tpriv->urbs = NULL;
-		usbi_mutex_unlock(&itransfer->lock);
-		break;
-	case LIBUSB_TRANSFER_TYPE_ISOCHRONOUS:
-		usbi_mutex_lock(&itransfer->lock);
-		if (tpriv->iso_urbs)
-			free_iso_urbs(tpriv);
-		usbi_mutex_unlock(&itransfer->lock);
-		break;
-	default:
-		usbi_err(TRANSFER_CTX(transfer),
-			"unknown endpoint type %d", transfer->type);
-	}
-}
-
-static int handle_bulk_completion(struct usbi_transfer *itransfer,
-	struct usbfs_urb *urb)
-{
-	struct linux_transfer_priv *tpriv = usbi_transfer_get_os_priv(itransfer);
-	struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	int urb_idx = urb - tpriv->urbs;
-
-	usbi_mutex_lock(&itransfer->lock);
-	usbi_dbg("handling completion status %d of bulk urb %d/%d", urb->status,
-		urb_idx + 1, tpriv->num_urbs);
-
-	tpriv->num_retired++;
-
-	if (tpriv->reap_action != NORMAL) {
-		/* cancelled, submit_fail, or completed early */
-		usbi_dbg("abnormal reap: urb status %d", urb->status);
-
-		/* even though we're in the process of cancelling, it's possible that
-		 * we may receive some data in these URBs that we don't want to lose.
-		 * examples:
-		 * 1. while the kernel is cancelling all the packets that make up an
-		 *    URB, a few of them might complete. so we get back a successful
-		 *    cancellation *and* some data.
-		 * 2. we receive a short URB which marks the early completion condition,
-		 *    so we start cancelling the remaining URBs. however, we're too
-		 *    slow and another URB completes (or at least completes partially).
-		 *    (this can't happen since we always use BULK_CONTINUATION.)
-		 *
-		 * When this happens, our objectives are not to lose any "surplus" data,
-		 * and also to stick it at the end of the previously-received data
-		 * (closing any holes), so that libusb reports the total amount of
-		 * transferred data and presents it in a contiguous chunk.
-		 */
-		if (urb->actual_length > 0) {
-			unsigned char *target = transfer->buffer + itransfer->transferred;
-			usbi_dbg("received %d bytes of surplus data", urb->actual_length);
-			if (urb->buffer != target) {
-				usbi_dbg("moving surplus data from offset %d to offset %d",
-					(unsigned char *) urb->buffer - transfer->buffer,
-					target - transfer->buffer);
-				memmove(target, urb->buffer, urb->actual_length);
-			}
-			itransfer->transferred += urb->actual_length;
-		}
-
-		if (tpriv->num_retired == tpriv->num_urbs) {
-			usbi_dbg("abnormal reap: last URB handled, reporting");
-			if (tpriv->reap_action != COMPLETED_EARLY &&
-			    tpriv->reap_status == LIBUSB_TRANSFER_COMPLETED)
-				tpriv->reap_status = LIBUSB_TRANSFER_ERROR;
-			goto completed;
-		}
-		goto out_unlock;
-	}
-
-	itransfer->transferred += urb->actual_length;
-
-	/* Many of these errors can occur on *any* urb of a multi-urb
-	 * transfer.  When they do, we tear down the rest of the transfer.
-	 */
-	switch (urb->status) {
-	case 0:
-		break;
-	case -EREMOTEIO: /* short transfer */
-		break;
-	case -ENOENT: /* cancelled */
-	case -ECONNRESET:
-		break;
-	case -ESHUTDOWN:
-		usbi_dbg("device removed");
-		tpriv->reap_status = LIBUSB_TRANSFER_NO_DEVICE;
-		goto cancel_remaining;
-	case -EPIPE:
-		usbi_dbg("detected endpoint stall");
-		if (tpriv->reap_status == LIBUSB_TRANSFER_COMPLETED)
-			tpriv->reap_status = LIBUSB_TRANSFER_STALL;
-		goto cancel_remaining;
-	case -EOVERFLOW:
-		/* overflow can only ever occur in the last urb */
-		usbi_dbg("overflow, actual_length=%d", urb->actual_length);
-		if (tpriv->reap_status == LIBUSB_TRANSFER_COMPLETED)
-			tpriv->reap_status = LIBUSB_TRANSFER_OVERFLOW;
-		goto completed;
-	case -ETIME:
-	case -EPROTO:
-	case -EILSEQ:
-		usbi_dbg("low level error %d", urb->status);
-		tpriv->reap_action = ERROR;
-		goto cancel_remaining;
-	default:
-		usbi_warn(ITRANSFER_CTX(itransfer),
-			"unrecognised urb status %d", urb->status);
-		tpriv->reap_action = ERROR;
-		goto cancel_remaining;
-	}
-
-	/* if we're the last urb or we got less data than requested then we're
-	 * done */
-	if (urb_idx == tpriv->num_urbs - 1) {
-		usbi_dbg("last URB in transfer --> complete!");
-		goto completed;
-	} else if (urb->actual_length < urb->buffer_length) {
-		usbi_dbg("short transfer %d/%d --> complete!",
-			urb->actual_length, urb->buffer_length);
-		if (tpriv->reap_action == NORMAL)
-			tpriv->reap_action = COMPLETED_EARLY;
-	} else
-		goto out_unlock;
-
-cancel_remaining:
-	if (ERROR == tpriv->reap_action && LIBUSB_TRANSFER_COMPLETED == tpriv->reap_status)
-		tpriv->reap_status = LIBUSB_TRANSFER_ERROR;
-
-	if (tpriv->num_retired == tpriv->num_urbs) /* nothing to cancel */
-		goto completed;
-
-	/* cancel remaining urbs and wait for their completion before
-	 * reporting results */
-	discard_urbs(itransfer, urb_idx + 1, tpriv->num_urbs);
-
-out_unlock:
-	usbi_mutex_unlock(&itransfer->lock);
-	return 0;
-
-completed:
-	free(tpriv->urbs);
-	tpriv->urbs = NULL;
-	usbi_mutex_unlock(&itransfer->lock);
-	return CANCELLED == tpriv->reap_action ?
-		usbi_handle_transfer_cancellation(itransfer) :
-		usbi_handle_transfer_completion(itransfer, tpriv->reap_status);
-}
-
-static int handle_iso_completion(struct usbi_transfer *itransfer,
-	struct usbfs_urb *urb)
-{
-	struct libusb_transfer *transfer =
-		USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	struct linux_transfer_priv *tpriv = usbi_transfer_get_os_priv(itransfer);
-	int num_urbs = tpriv->num_urbs;
-	int urb_idx = 0;
-	int i;
-	enum libusb_transfer_status status = LIBUSB_TRANSFER_COMPLETED;
-
-	usbi_mutex_lock(&itransfer->lock);
-	for (i = 0; i < num_urbs; i++) {
-		if (urb == tpriv->iso_urbs[i]) {
-			urb_idx = i + 1;
-			break;
-		}
-	}
-	if (urb_idx == 0) {
-		usbi_err(TRANSFER_CTX(transfer), "could not locate urb!");
-		usbi_mutex_unlock(&itransfer->lock);
-		return LIBUSB_ERROR_NOT_FOUND;
-	}
-
-	usbi_dbg("handling completion status %d of iso urb %d/%d", urb->status,
-		urb_idx, num_urbs);
-
-	/* copy isochronous results back in */
-
-	for (i = 0; i < urb->number_of_packets; i++) {
-		struct usbfs_iso_packet_desc *urb_desc = &urb->iso_frame_desc[i];
-		struct libusb_iso_packet_descriptor *lib_desc =
-			&transfer->iso_packet_desc[tpriv->iso_packet_offset++];
-		lib_desc->status = urb_desc->status;
-		lib_desc->actual_length = urb_desc->actual_length;
-	}
-
-	tpriv->num_retired++;
-
-	if (tpriv->reap_action != NORMAL) { /* cancelled or submit_fail */
-		usbi_dbg("CANCEL: urb status %d", urb->status);
-
-		if (status == LIBUSB_TRANSFER_COMPLETED)
-			status = LIBUSB_TRANSFER_ERROR;
-
-		if (tpriv->num_retired == num_urbs) {
-			usbi_dbg("CANCEL: last URB handled, reporting");
-			free_iso_urbs(tpriv);
-			if (tpriv->reap_action == CANCELLED) {
-				usbi_mutex_unlock(&itransfer->lock);
-				return usbi_handle_transfer_cancellation(itransfer);
-			} else {
-				usbi_mutex_unlock(&itransfer->lock);
-				return usbi_handle_transfer_completion(itransfer,
-					LIBUSB_TRANSFER_ERROR);
-			}
-		}
-		goto out;
-	}
-
-	switch (urb->status) {
-	case 0:
-		break;
-	case -ENOENT: /* cancelled */
-		break;
-	case -ESHUTDOWN:
-		usbi_dbg("device removed");
-		status = LIBUSB_TRANSFER_NO_DEVICE;
-		break;
-	case -ETIME:
-	case -EPROTO:
-	case -EILSEQ:
-		usbi_dbg("low-level USB error %d", urb->status);
-		break;
-	default:
-		usbi_warn(TRANSFER_CTX(transfer),
-			"unrecognised urb status %d", urb->status);
-		break;
-	}
-
-	/* if we're the last urb or we got less data than requested then we're
-	 * done */
-	if (urb_idx == num_urbs) {
-		usbi_dbg("last URB in transfer --> complete!");
-		free_iso_urbs(tpriv);
-		usbi_mutex_unlock(&itransfer->lock);
-		return usbi_handle_transfer_completion(itransfer, status);
-	}
-
-out:
-	usbi_mutex_unlock(&itransfer->lock);
-	return 0;
-}
-
-static int handle_control_completion(struct usbi_transfer *itransfer,
-	struct usbfs_urb *urb)
-{
-	struct linux_transfer_priv *tpriv = usbi_transfer_get_os_priv(itransfer);
-	int status;
-
-	usbi_mutex_lock(&itransfer->lock);
-	usbi_dbg("handling completion status %d", urb->status);
-
-	itransfer->transferred += urb->actual_length;
-
-	if (tpriv->reap_action == CANCELLED) {
-		if (urb->status != 0 && urb->status != -ENOENT)
-			usbi_warn(ITRANSFER_CTX(itransfer),
-				"cancel: unrecognised urb status %d", urb->status);
-		free(tpriv->urbs);
-		tpriv->urbs = NULL;
-		usbi_mutex_unlock(&itransfer->lock);
-		return usbi_handle_transfer_cancellation(itransfer);
-	}
-
-	switch (urb->status) {
-	case 0:
-		status = LIBUSB_TRANSFER_COMPLETED;
-		break;
-	case -ENOENT: /* cancelled */
-		status = LIBUSB_TRANSFER_CANCELLED;
-		break;
-	case -ESHUTDOWN:
-		usbi_dbg("device removed");
-		status = LIBUSB_TRANSFER_NO_DEVICE;
-		break;
-	case -EPIPE:
-		usbi_dbg("unsupported control request");
-		status = LIBUSB_TRANSFER_STALL;
-		break;
-	case -ETIME:
-	case -EPROTO:
-	case -EILSEQ:
-		usbi_dbg("low-level bus error occurred");
-		status = LIBUSB_TRANSFER_ERROR;
-		break;
-	default:
-		usbi_warn(ITRANSFER_CTX(itransfer),
-			"unrecognised urb status %d", urb->status);
-		status = LIBUSB_TRANSFER_ERROR;
-		break;
-	}
-
-	free(tpriv->urbs);
-	tpriv->urbs = NULL;
-	usbi_mutex_unlock(&itransfer->lock);
-	return usbi_handle_transfer_completion(itransfer, status);
-}
-
-static int reap_for_handle(struct libusb_device_handle *handle)
-{
-	struct linux_device_handle_priv *hpriv = _device_handle_priv(handle);
-	int r;
-	struct usbfs_urb *urb;
-	struct usbi_transfer *itransfer;
-	struct libusb_transfer *transfer;
-
-	r = ioctl(hpriv->fd, IOCTL_USBFS_REAPURBNDELAY, &urb);
-	if (r == -1 && errno == EAGAIN)
-		return 1;
-	if (r < 0) {
-		if (errno == ENODEV)
-			return LIBUSB_ERROR_NO_DEVICE;
-
-		usbi_err(HANDLE_CTX(handle), "reap failed error %d errno=%d",
-			r, errno);
-		return LIBUSB_ERROR_IO;
-	}
-
-	itransfer = urb->usercontext;
-	transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-
-	usbi_dbg("urb type=%d status=%d transferred=%d", urb->type, urb->status,
-		urb->actual_length);
-
-	switch (transfer->type) {
-	case LIBUSB_TRANSFER_TYPE_ISOCHRONOUS:
-		return handle_iso_completion(itransfer, urb);
-	case LIBUSB_TRANSFER_TYPE_BULK:
-	case LIBUSB_TRANSFER_TYPE_INTERRUPT:
-		return handle_bulk_completion(itransfer, urb);
-	case LIBUSB_TRANSFER_TYPE_CONTROL:
-		return handle_control_completion(itransfer, urb);
-	default:
-		usbi_err(HANDLE_CTX(handle), "unrecognised endpoint type %x",
-			transfer->type);
-		return LIBUSB_ERROR_OTHER;
-	}
-}
-
-static int op_handle_events(struct libusb_context *ctx,
-	struct pollfd *fds, POLL_NFDS_TYPE nfds, int num_ready)
-{
-	int r;
-	int i = 0;
-
-	usbi_mutex_lock(&ctx->open_devs_lock);
-	for (i = 0; i < nfds && num_ready > 0; i++) {
-		struct pollfd *pollfd = &fds[i];
-		struct libusb_device_handle *handle;
-		struct linux_device_handle_priv *hpriv = NULL;
-
-		if (!pollfd->revents)
-			continue;
-
-		num_ready--;
-		list_for_each_entry(handle, &ctx->open_devs, list, struct libusb_device_handle) {
-			hpriv = _device_handle_priv(handle);
-			if (hpriv->fd == pollfd->fd)
-				break;
-		}
-
-		if (pollfd->revents & POLLERR) {
-			usbi_remove_pollfd(HANDLE_CTX(handle), hpriv->fd);
-			usbi_handle_disconnect(handle);
-			continue;
-		}
-
-		r = reap_for_handle(handle);
-		if (r == 1 || r == LIBUSB_ERROR_NO_DEVICE)
-			continue;
-		else if (r < 0)
-			goto out;
-	}
-
-	r = 0;
-out:
-	usbi_mutex_unlock(&ctx->open_devs_lock);
-	return r;
-}
-
-static int op_clock_gettime(int clk_id, struct timespec *tp)
-{
-	switch (clk_id) {
-	case USBI_CLOCK_MONOTONIC:
-		return clock_gettime(monotonic_clkid, tp);
-	case USBI_CLOCK_REALTIME:
-		return clock_gettime(CLOCK_REALTIME, tp);
-	default:
-		return LIBUSB_ERROR_INVALID_PARAM;
-  }
-}
-
-#ifdef USBI_TIMERFD_AVAILABLE
-static clockid_t op_get_timerfd_clockid(void)
-{
-	return monotonic_clkid;
-
-}
-#endif
-
-const struct usbi_os_backend linux_usbfs_backend = {
-	.name = "Linux usbfs",
-	.init = op_init,
-	.exit = NULL,
-	.get_device_list = op_get_device_list,
-	.get_device_descriptor = op_get_device_descriptor,
-	.get_active_config_descriptor = op_get_active_config_descriptor,
-	.get_config_descriptor = op_get_config_descriptor,
-
-	.open = op_open,
-	.close = op_close,
-	.get_configuration = op_get_configuration,
-	.set_configuration = op_set_configuration,
-	.claim_interface = op_claim_interface,
-	.release_interface = op_release_interface,
-
-	.set_interface_altsetting = op_set_interface,
-	.clear_halt = op_clear_halt,
-	.reset_device = op_reset_device,
-
-	.kernel_driver_active = op_kernel_driver_active,
-	.detach_kernel_driver = op_detach_kernel_driver,
-	.attach_kernel_driver = op_attach_kernel_driver,
-
-	.destroy_device = op_destroy_device,
-
-	.submit_transfer = op_submit_transfer,
-	.cancel_transfer = op_cancel_transfer,
-	.clear_transfer_priv = op_clear_transfer_priv,
-
-	.handle_events = op_handle_events,
-
-	.clock_gettime = op_clock_gettime,
-
-#ifdef USBI_TIMERFD_AVAILABLE
-	.get_timerfd_clockid = op_get_timerfd_clockid,
-#endif
-
-	.device_priv_size = sizeof(struct linux_device_priv),
-	.device_handle_priv_size = sizeof(struct linux_device_handle_priv),
-	.transfer_priv_size = sizeof(struct linux_transfer_priv),
-	.add_iso_packet_size = 0,
-};
-
diff --git a/third_party/libusb/libusb/os/linux_usbfs.h b/third_party/libusb/libusb/os/linux_usbfs.h
deleted file mode 100644
index 93e7f31..0000000
--- a/third_party/libusb/libusb/os/linux_usbfs.h
+++ /dev/null
@@ -1,138 +0,0 @@
-/*
- * usbfs header structures
- * Copyright (C) 2007 Daniel Drake <dsd@gentoo.org>
- * Copyright (c) 2001 Johannes Erdfelt <johannes@erdfelt.com>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#ifndef LIBUSB_USBFS_H
-#define LIBUSB_USBFS_H
-
-#define SYSFS_DEVICE_PATH "/sys/bus/usb/devices"
-
-struct usbfs_ctrltransfer {
-	/* keep in sync with usbdevice_fs.h:usbdevfs_ctrltransfer */
-	uint8_t  bmRequestType;
-	uint8_t  bRequest;
-	uint16_t wValue;
-	uint16_t wIndex;
-	uint16_t wLength;
-
-	uint32_t timeout;	/* in milliseconds */
-
-	/* pointer to data */
-	void *data;
-};
-
-struct usbfs_bulktransfer {
-	/* keep in sync with usbdevice_fs.h:usbdevfs_bulktransfer */
-	unsigned int ep;
-	unsigned int len;
-	unsigned int timeout;	/* in milliseconds */
-
-	/* pointer to data */
-	void *data;
-};
-
-struct usbfs_setinterface {
-	/* keep in sync with usbdevice_fs.h:usbdevfs_setinterface */
-	unsigned int interface;
-	unsigned int altsetting;
-};
-
-#define USBFS_MAXDRIVERNAME 255
-
-struct usbfs_getdriver {
-	unsigned int interface;
-	char driver[USBFS_MAXDRIVERNAME + 1];
-};
-
-#define USBFS_URB_SHORT_NOT_OK		0x01
-#define USBFS_URB_ISO_ASAP			0x02
-#define USBFS_URB_BULK_CONTINUATION	0x04
-#define USBFS_URB_QUEUE_BULK		0x10
-
-enum usbfs_urb_type {
-	USBFS_URB_TYPE_ISO = 0,
-	USBFS_URB_TYPE_INTERRUPT = 1,
-	USBFS_URB_TYPE_CONTROL = 2,
-	USBFS_URB_TYPE_BULK = 3,
-};
-
-struct usbfs_iso_packet_desc {
-	unsigned int length;
-	unsigned int actual_length;
-	unsigned int status;
-};
-
-#define MAX_ISO_BUFFER_LENGTH		32768
-#define MAX_BULK_BUFFER_LENGTH		16384
-#define MAX_CTRL_BUFFER_LENGTH		4096
-
-struct usbfs_urb {
-	unsigned char type;
-	unsigned char endpoint;
-	int status;
-	unsigned int flags;
-	void *buffer;
-	int buffer_length;
-	int actual_length;
-	int start_frame;
-	int number_of_packets;
-	int error_count;
-	unsigned int signr;
-	void *usercontext;
-	struct usbfs_iso_packet_desc iso_frame_desc[0];
-};
-
-struct usbfs_connectinfo {
-	unsigned int devnum;
-	unsigned char slow;
-};
-
-struct usbfs_ioctl {
-	int ifno;	/* interface 0..N ; negative numbers reserved */
-	int ioctl_code;	/* MUST encode size + direction of data so the
-			 * macros in <asm/ioctl.h> give correct values */
-	void *data;	/* param buffer (in, or out) */
-};
-
-struct usbfs_hub_portinfo {
-	unsigned char numports;
-	unsigned char port[127];	/* port to device num mapping */
-};
-
-#define IOCTL_USBFS_CONTROL	_IOWR('U', 0, struct usbfs_ctrltransfer)
-#define IOCTL_USBFS_BULK		_IOWR('U', 2, struct usbfs_bulktransfer)
-#define IOCTL_USBFS_RESETEP	_IOR('U', 3, unsigned int)
-#define IOCTL_USBFS_SETINTF	_IOR('U', 4, struct usbfs_setinterface)
-#define IOCTL_USBFS_SETCONFIG	_IOR('U', 5, unsigned int)
-#define IOCTL_USBFS_GETDRIVER	_IOW('U', 8, struct usbfs_getdriver)
-#define IOCTL_USBFS_SUBMITURB	_IOR('U', 10, struct usbfs_urb)
-#define IOCTL_USBFS_DISCARDURB	_IO('U', 11)
-#define IOCTL_USBFS_REAPURB	_IOW('U', 12, void *)
-#define IOCTL_USBFS_REAPURBNDELAY	_IOW('U', 13, void *)
-#define IOCTL_USBFS_CLAIMINTF	_IOR('U', 15, unsigned int)
-#define IOCTL_USBFS_RELEASEINTF	_IOR('U', 16, unsigned int)
-#define IOCTL_USBFS_CONNECTINFO	_IOW('U', 17, struct usbfs_connectinfo)
-#define IOCTL_USBFS_IOCTL         _IOWR('U', 18, struct usbfs_ioctl)
-#define IOCTL_USBFS_HUB_PORTINFO	_IOR('U', 19, struct usbfs_hub_portinfo)
-#define IOCTL_USBFS_RESET		_IO('U', 20)
-#define IOCTL_USBFS_CLEAR_HALT	_IOR('U', 21, unsigned int)
-#define IOCTL_USBFS_DISCONNECT	_IO('U', 22)
-#define IOCTL_USBFS_CONNECT	_IO('U', 23)
-
-#endif
diff --git a/third_party/libusb/libusb/os/poll_posix.h b/third_party/libusb/libusb/os/poll_posix.h
deleted file mode 100644
index 0e5e7f5b..0000000
--- a/third_party/libusb/libusb/os/poll_posix.h
+++ /dev/null
@@ -1,10 +0,0 @@
-#ifndef LIBUSB_POLL_POSIX_H
-#define LIBUSB_POLL_POSIX_H
-
-#define usbi_write write
-#define usbi_read read
-#define usbi_close close
-#define usbi_pipe pipe
-#define usbi_poll poll
-
-#endif /* LIBUSB_POLL_POSIX_H */
diff --git a/third_party/libusb/libusb/os/poll_windows.c b/third_party/libusb/libusb/os/poll_windows.c
deleted file mode 100644
index c997c81..0000000
--- a/third_party/libusb/libusb/os/poll_windows.c
+++ /dev/null
@@ -1,839 +0,0 @@
-/*
- * poll_windows: poll compatibility wrapper for Windows
- * Copyright (C) 2009-2010 Pete Batard <pbatard@gmail.com>
- * With contributions from Michael Plante, Orin Eman et al.
- * Parts of poll implementation from libusb-win32, by Stephan Meyer et al.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- *
- */
-
-/*
- * poll() and pipe() Windows compatibility layer for libusb 1.0
- *
- * The way this layer works is by using OVERLAPPED with async I/O transfers, as
- * OVERLAPPED have an associated event which is flagged for I/O completion.
- *
- * For USB pollable async I/O, you would typically:
- * - obtain a Windows HANDLE to a file or device that has been opened in
- *   OVERLAPPED mode
- * - call usbi_create_fd with this handle to obtain a custom fd.
- *   Note that if you need simultaneous R/W access, you need to call create_fd
- *   twice, once in _O_RDONLY and once in _O_WRONLY mode to obtain 2 separate
- *   pollable fds
- * - leave the core functions call the poll routine and flag POLLIN/POLLOUT
- *
- * The pipe pollable synchronous I/O works using the overlapped event associated
- * with a fake pipe. The read/write functions are only meant to be used in that
- * context.
- */
-#include <errno.h>
-#include <fcntl.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <io.h>
-
-#include <libusbi.h>
-
-// Uncomment to debug the polling layer
-//#define DEBUG_POLL_WINDOWS
-#if defined(DEBUG_POLL_WINDOWS)
-#define poll_dbg usbi_dbg
-#else
-// MSVC6 cannot use a variadic argument and non MSVC
-// compilers produce warnings if parenthesis are ommitted.
-#if defined(_MSC_VER)
-#define poll_dbg
-#else
-#define poll_dbg(...)
-#endif
-#endif
-
-#if defined(_PREFAST_)
-#pragma warning(disable:28719)
-#endif
-
-#if defined(__CYGWIN__)
-// cygwin produces a warning unless these prototypes are defined
-extern int _open(char* name, int flags);
-extern int _close(int fd);
-extern int _snprintf(char *buffer, size_t count, const char *format, ...);
-#define NUL_DEVICE "/dev/null"
-#else
-#define NUL_DEVICE "NUL"
-#endif
-
-#define CHECK_INIT_POLLING do {if(!is_polling_set) init_polling();} while(0)
-
-// public fd data
-const struct winfd INVALID_WINFD = {-1, INVALID_HANDLE_VALUE, NULL, RW_NONE};
-struct winfd poll_fd[MAX_FDS];
-// internal fd data
-struct {
-	CRITICAL_SECTION mutex; // lock for fds
-	// Additional variables for XP CancelIoEx partial emulation
-	HANDLE original_handle;
-	DWORD thread_id;
-} _poll_fd[MAX_FDS];
-
-// globals
-BOOLEAN is_polling_set = FALSE;
-#if defined(DYNAMIC_FDS)
-HANDLE fd_update = INVALID_HANDLE_VALUE;	// event to notify poll of fd update
-HANDLE new_fd[MAX_FDS];		// overlapped event handles for fds created since last poll
-unsigned nb_new_fds = 0;	// nb new fds created since last poll
-usbi_mutex_t new_fd_mutex;	// mutex required for the above
-#endif
-LONG pipe_number = 0;
-static volatile LONG compat_spinlock = 0;
-
-// CancelIoEx, available on Vista and later only, provides the ability to cancel
-// a single transfer (OVERLAPPED) when used. As it may not be part of any of the
-// platform headers, we hook into the Kernel32 system DLL directly to seek it.
-static BOOL (__stdcall *pCancelIoEx)(HANDLE, LPOVERLAPPED) = NULL;
-#define CancelIoEx_Available (pCancelIoEx != NULL)
-static __inline BOOL cancel_io(int _index)
-{
-	if ((_index < 0) || (_index >= MAX_FDS)) {
-		return FALSE;
-	}
-
-	if ( (poll_fd[_index].fd < 0) || (poll_fd[_index].handle == INVALID_HANDLE_VALUE)
-	  || (poll_fd[_index].handle == 0) || (poll_fd[_index].overlapped == NULL) ) {
-		return TRUE;
-	}
-	if (CancelIoEx_Available) {
-		return (*pCancelIoEx)(poll_fd[_index].handle, poll_fd[_index].overlapped);
-	}
-	if (_poll_fd[_index].thread_id == GetCurrentThreadId()) {
-		return CancelIo(poll_fd[_index].handle);
-	}
-	usbi_warn(NULL, "Unable to cancel I/O that was started from another thread");
-	return FALSE;
-}
-
-// Init
-void init_polling(void)
-{
-	int i;
-
-	while (InterlockedExchange((LONG *)&compat_spinlock, 1) == 1) {
-		SleepEx(0, TRUE);
-	}
-	if (!is_polling_set) {
-		pCancelIoEx = (BOOL (__stdcall *)(HANDLE,LPOVERLAPPED))
-			GetProcAddress(GetModuleHandleA("KERNEL32"), "CancelIoEx");
-		usbi_dbg("Will use CancelIo%s for I/O cancellation",
-			CancelIoEx_Available?"Ex":"");
-		for (i=0; i<MAX_FDS; i++) {
-			poll_fd[i] = INVALID_WINFD;
-			_poll_fd[i].original_handle = INVALID_HANDLE_VALUE;
-			_poll_fd[i].thread_id = 0;
-			InitializeCriticalSection(&_poll_fd[i].mutex);
-		}
-#if defined(DYNAMIC_FDS)
-		// We need to create an update event so that poll is warned when there
-		// are new/deleted fds during a timeout wait operation
-		fd_update = CreateEvent(NULL, TRUE, FALSE, NULL);
-		if (fd_update == NULL) {
-			usbi_err(NULL, "unable to create update event");
-		}
-		usbi_mutex_init(&new_fd_mutex, NULL);
-		nb_new_fds = 0;
-#endif
-		is_polling_set = TRUE;
-	}
-	compat_spinlock = 0;
-}
-
-// Internal function to retrieve the table index (and lock the fd mutex)
-int _fd_to_index_and_lock(int fd)
-{
-	int i;
-
-	if (fd <= 0)
-		return -1;
-
-	for (i=0; i<MAX_FDS; i++) {
-		if (poll_fd[i].fd == fd) {
-			EnterCriticalSection(&_poll_fd[i].mutex);
-			// fd might have changed before we got to critical
-			if (poll_fd[i].fd != fd) {
-				LeaveCriticalSection(&_poll_fd[i].mutex);
-				continue;
-			}
-			return i;
-		}
-	}
-	return -1;
-}
-
-OVERLAPPED *create_overlapped(void)
-{
-	OVERLAPPED *overlapped = calloc(1, sizeof(OVERLAPPED));
-	if (overlapped == NULL) {
-		return NULL;
-	}
-	overlapped->hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
-	if(overlapped->hEvent == NULL) {
-		free (overlapped);
-		return NULL;
-	}
-	return overlapped;
-}
-
-void free_overlapped(OVERLAPPED *overlapped)
-{
-	if (overlapped == NULL)
-		return;
-
-	if ( (overlapped->hEvent != 0)
-	  && (overlapped->hEvent != INVALID_HANDLE_VALUE) ) {
-		CloseHandle(overlapped->hEvent);
-	}
-	free(overlapped);
-}
-
-void reset_overlapped(OVERLAPPED *overlapped)
-{
-	HANDLE event_handle;
-	if (overlapped == NULL)
-		return;
-
-	event_handle = overlapped->hEvent;
-	if (event_handle != NULL) {
-		ResetEvent(event_handle);
-	}
-	memset(overlapped, 0, sizeof(OVERLAPPED));
-	overlapped->hEvent = event_handle;
-}
-
-void exit_polling(void)
-{
-	int i;
-
-	while (InterlockedExchange((LONG *)&compat_spinlock, 1) == 1) {
-		SleepEx(0, TRUE);
-	}
-	if (is_polling_set) {
-		is_polling_set = FALSE;
-
-		for (i=0; i<MAX_FDS; i++) {
-			// Cancel any async I/O (handle can be invalid)
-			cancel_io(i);
-			// If anything was pending on that I/O, it should be
-			// terminating, and we should be able to access the fd
-			// mutex lock before too long
-			EnterCriticalSection(&_poll_fd[i].mutex);
-			if ( (poll_fd[i].fd > 0) && (poll_fd[i].handle != INVALID_HANDLE_VALUE) && (poll_fd[i].handle != 0)
-			  && (GetFileType(poll_fd[i].handle) == FILE_TYPE_UNKNOWN) ) {
-				_close(poll_fd[i].fd);
-			}
-			free_overlapped(poll_fd[i].overlapped);
-			if (!CancelIoEx_Available) {
-				// Close duplicate handle
-				if (_poll_fd[i].original_handle != INVALID_HANDLE_VALUE) {
-					CloseHandle(poll_fd[i].handle);
-				}
-			}
-			poll_fd[i] = INVALID_WINFD;
-#if defined(DYNAMIC_FDS)
-			usbi_mutex_destroy(&new_fd_mutex);
-			CloseHandle(fd_update);
-			fd_update = INVALID_HANDLE_VALUE;
-#endif
-			LeaveCriticalSection(&_poll_fd[i].mutex);
-			DeleteCriticalSection(&_poll_fd[i].mutex);
-		}
-	}
-	compat_spinlock = 0;
-}
-
-/*
- * Create a fake pipe.
- * As libusb only uses pipes for signaling, all we need from a pipe is an
- * event. To that extent, we create a single wfd and overlapped as a means
- * to access that event.
- */
-int usbi_pipe(int filedes[2])
-{
-	int i;
-	OVERLAPPED* overlapped;
-
-	CHECK_INIT_POLLING;
-
-	overlapped = calloc(1, sizeof(OVERLAPPED));
-	if (overlapped == NULL) {
-		return -1;
-	}
-	// The overlapped must have status pending for signaling to work in poll
-	overlapped->Internal = STATUS_PENDING;
-	overlapped->InternalHigh = 0;
-
-	// Read end of the "pipe"
-	filedes[0] = _open(NUL_DEVICE, _O_WRONLY);
-	if (filedes[0] < 0) {
-		usbi_err(NULL, "could not create pipe: errno %d", errno);
-		goto out1;
-	}
-	// We can use the same handle for both ends
-	filedes[1] = filedes[0];
-	poll_dbg("pipe filedes = %d", filedes[0]);
-
-	// Note: manual reset must be true (second param) as the reset occurs in read
-	overlapped->hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
-	if(!overlapped->hEvent) {
-		goto out2;
-	}
-
-	for (i=0; i<MAX_FDS; i++) {
-		if (poll_fd[i].fd < 0) {
-			EnterCriticalSection(&_poll_fd[i].mutex);
-			// fd might have been allocated before we got to critical
-			if (poll_fd[i].fd >= 0) {
-				LeaveCriticalSection(&_poll_fd[i].mutex);
-				continue;
-			}
-
-			poll_fd[i].fd = filedes[0];
-			poll_fd[i].handle = DUMMY_HANDLE;
-			poll_fd[i].overlapped = overlapped;
-			// There's no polling on the write end, so we just use READ for our needs
-			poll_fd[i].rw = RW_READ;
-			_poll_fd[i].original_handle = INVALID_HANDLE_VALUE;
-			LeaveCriticalSection(&_poll_fd[i].mutex);
-			return 0;
-		}
-	}
-
-	CloseHandle(overlapped->hEvent);
-out2:
-	_close(filedes[0]);
-out1:
-	free(overlapped);
-	return -1;
-}
-
-/*
- * Create both an fd and an OVERLAPPED from an open Windows handle, so that
- * it can be used with our polling function
- * The handle MUST support overlapped transfers (usually requires CreateFile
- * with FILE_FLAG_OVERLAPPED)
- * Return a pollable file descriptor struct, or INVALID_WINFD on error
- *
- * Note that the fd returned by this function is a per-transfer fd, rather
- * than a per-session fd and cannot be used for anything else but our
- * custom functions (the fd itself points to the NUL: device)
- * if you plan to do R/W on the same handle, you MUST create 2 fds: one for
- * read and one for write. Using a single R/W fd is unsupported and will
- * produce unexpected results
- */
-struct winfd usbi_create_fd(HANDLE handle, int access_mode)
-{
-	int i, fd;
-	struct winfd wfd = INVALID_WINFD;
-	OVERLAPPED* overlapped = NULL;
-
-	CHECK_INIT_POLLING;
-
-	if ((handle == 0) || (handle == INVALID_HANDLE_VALUE)) {
-		return INVALID_WINFD;
-	}
-
-	if ((access_mode != _O_RDONLY) && (access_mode != _O_WRONLY)) {
-		usbi_warn(NULL, "only one of _O_RDONLY or _O_WRONLY are supported.\n"
-			"If you want to poll for R/W simultaneously, create multiple fds from the same handle.");
-		return INVALID_WINFD;
-	}
-	if (access_mode == _O_RDONLY) {
-		wfd.rw = RW_READ;
-	} else {
-		wfd.rw = RW_WRITE;
-	}
-
-	// Ensure that we get a non system conflicting unique fd, using
-	// the same fd attribution system as the pipe ends
-	fd = _open(NUL_DEVICE, _O_WRONLY);
-	if (fd < 0) {
-		return INVALID_WINFD;
-	}
-
-	overlapped = create_overlapped();
-	if(overlapped == NULL) {
-		_close(fd);
-		return INVALID_WINFD;
-	}
-
-	for (i=0; i<MAX_FDS; i++) {
-		if (poll_fd[i].fd < 0) {
-			EnterCriticalSection(&_poll_fd[i].mutex);
-			// fd might have been removed before we got to critical
-			if (poll_fd[i].fd >= 0) {
-				LeaveCriticalSection(&_poll_fd[i].mutex);
-				continue;
-			}
-			wfd.fd = fd;
-			// Attempt to emulate some of the CancelIoEx behaviour on platforms
-			// that don't have it
-			if (!CancelIoEx_Available) {
-				_poll_fd[i].thread_id = GetCurrentThreadId();
-				if (!DuplicateHandle(GetCurrentProcess(), handle, GetCurrentProcess(),
-					&wfd.handle, 0, TRUE, DUPLICATE_SAME_ACCESS)) {
-					usbi_dbg("could not duplicate handle for CancelIo - using original one");
-					wfd.handle = handle;
-					// Make sure we won't close the original handle on fd deletion then
-					_poll_fd[i].original_handle = INVALID_HANDLE_VALUE;
-				} else {
-					_poll_fd[i].original_handle = handle;
-				}
-			} else {
-				wfd.handle = handle;
-			}
-			wfd.overlapped = overlapped;
-			memcpy(&poll_fd[i], &wfd, sizeof(struct winfd));
-			LeaveCriticalSection(&_poll_fd[i].mutex);
-#if defined(DYNAMIC_FDS)
-			usbi_mutex_lock(&new_fd_mutex);
-			new_fd[nb_new_fds++] = overlapped->hEvent;
-			usbi_mutex_unlock(&new_fd_mutex);
-			// Notify poll that fds have been updated
-			SetEvent(fd_update);
-#endif
-			return wfd;
-		}
-	}
-	free_overlapped(overlapped);
-	_close(fd);
-	return INVALID_WINFD;
-}
-
-void _free_index(int _index)
-{
-	// Cancel any async IO (Don't care about the validity of our handles for this)
-	cancel_io(_index);
-	// close fake handle for devices
-	if ( (poll_fd[_index].handle != INVALID_HANDLE_VALUE) && (poll_fd[_index].handle != 0)
-	  && (GetFileType(poll_fd[_index].handle) == FILE_TYPE_UNKNOWN) ) {
-		_close(poll_fd[_index].fd);
-	}
-	// close the duplicate handle (if we have an actual duplicate)
-	if (!CancelIoEx_Available) {
-		if (_poll_fd[_index].original_handle != INVALID_HANDLE_VALUE) {
-			CloseHandle(poll_fd[_index].handle);
-		}
-		_poll_fd[_index].original_handle = INVALID_HANDLE_VALUE;
-		_poll_fd[_index].thread_id = 0;
-	}
-	free_overlapped(poll_fd[_index].overlapped);
-	poll_fd[_index] = INVALID_WINFD;
-}
-
-/*
- * Release a pollable file descriptor.
- *
- * Note that the associated Windows handle is not closed by this call
- */
-void usbi_free_fd(int fd)
-{
-	int _index;
-
-	CHECK_INIT_POLLING;
-
-	_index = _fd_to_index_and_lock(fd);
-	if (_index < 0) {
-		return;
-	}
-	_free_index(_index);
-	LeaveCriticalSection(&_poll_fd[_index].mutex);
-}
-
-/*
- * The functions below perform various conversions between fd, handle and OVERLAPPED
- */
-struct winfd fd_to_winfd(int fd)
-{
-	int i;
-	struct winfd wfd;
-
-	CHECK_INIT_POLLING;
-
-	if (fd <= 0)
-		return INVALID_WINFD;
-
-	for (i=0; i<MAX_FDS; i++) {
-		if (poll_fd[i].fd == fd) {
-			EnterCriticalSection(&_poll_fd[i].mutex);
-			// fd might have been deleted before we got to critical
-			if (poll_fd[i].fd != fd) {
-				LeaveCriticalSection(&_poll_fd[i].mutex);
-				continue;
-			}
-			memcpy(&wfd, &poll_fd[i], sizeof(struct winfd));
-			LeaveCriticalSection(&_poll_fd[i].mutex);
-			return wfd;
-		}
-	}
-	return INVALID_WINFD;
-}
-
-struct winfd handle_to_winfd(HANDLE handle)
-{
-	int i;
-	struct winfd wfd;
-
-	CHECK_INIT_POLLING;
-
-	if ((handle == 0) || (handle == INVALID_HANDLE_VALUE))
-		return INVALID_WINFD;
-
-	for (i=0; i<MAX_FDS; i++) {
-		if (poll_fd[i].handle == handle) {
-			EnterCriticalSection(&_poll_fd[i].mutex);
-			// fd might have been deleted before we got to critical
-			if (poll_fd[i].handle != handle) {
-				LeaveCriticalSection(&_poll_fd[i].mutex);
-				continue;
-			}
-			memcpy(&wfd, &poll_fd[i], sizeof(struct winfd));
-			LeaveCriticalSection(&_poll_fd[i].mutex);
-			return wfd;
-		}
-	}
-	return INVALID_WINFD;
-}
-
-struct winfd overlapped_to_winfd(OVERLAPPED* overlapped)
-{
-	int i;
-	struct winfd wfd;
-
-	CHECK_INIT_POLLING;
-
-	if (overlapped == NULL)
-		return INVALID_WINFD;
-
-	for (i=0; i<MAX_FDS; i++) {
-		if (poll_fd[i].overlapped == overlapped) {
-			EnterCriticalSection(&_poll_fd[i].mutex);
-			// fd might have been deleted before we got to critical
-			if (poll_fd[i].overlapped != overlapped) {
-				LeaveCriticalSection(&_poll_fd[i].mutex);
-				continue;
-			}
-			memcpy(&wfd, &poll_fd[i], sizeof(struct winfd));
-			LeaveCriticalSection(&_poll_fd[i].mutex);
-			return wfd;
-		}
-	}
-	return INVALID_WINFD;
-}
-
-/*
- * POSIX poll equivalent, using Windows OVERLAPPED
- * Currently, this function only accepts one of POLLIN or POLLOUT per fd
- * (but you can create multiple fds from the same handle for read and write)
- */
-int usbi_poll(struct pollfd *fds, unsigned int nfds, int timeout)
-{
-	unsigned i;
-	int _index, object_index, triggered;
-	HANDLE *handles_to_wait_on;
-	int *handle_to_index;
-	DWORD nb_handles_to_wait_on = 0;
-	DWORD ret;
-
-#if defined(DYNAMIC_FDS)
-	DWORD nb_extra_handles = 0;
-	unsigned j;
-
-	// To address the possibility of missing new fds between the time the new
-	// pollable fd set is assembled, and the ResetEvent() call below, an
-	// additional new_fd[] HANDLE table is used for any new fd that was created
-	// since the last call to poll (see below)
-	ResetEvent(fd_update);
-
-	// At this stage, any new fd creation will be detected through the fd_update
-	// event notification, and any previous creation that we may have missed
-	// will be picked up through the existing new_fd[] table.
-#endif
-
-	CHECK_INIT_POLLING;
-
-	triggered = 0;
-	handles_to_wait_on = malloc((nfds+1)*sizeof(HANDLE));	// +1 for fd_update
-	handle_to_index = malloc(nfds*sizeof(int));
-	if ((handles_to_wait_on == NULL) || (handle_to_index == NULL)) {
-		errno = ENOMEM;
-		triggered = -1;
-		goto poll_exit;
-	}
-
-	for (i = 0; i < nfds; ++i) {
-		fds[i].revents = 0;
-
-		// Only one of POLLIN or POLLOUT can be selected with this version of poll (not both)
-		if ((fds[i].events & ~POLLIN) && (!(fds[i].events & POLLOUT))) {
-			fds[i].revents |= POLLERR;
-			errno = EACCES;
-			usbi_warn(NULL, "unsupported set of events");
-			triggered = -1;
-			goto poll_exit;
-		}
-
-		_index = _fd_to_index_and_lock(fds[i].fd);
-		poll_dbg("fd[%d]=%d: (overlapped=%p) got events %04X", i, poll_fd[_index].fd, poll_fd[_index].overlapped, fds[i].events);
-
-		if ( (_index < 0) || (poll_fd[_index].handle == INVALID_HANDLE_VALUE)
-		  || (poll_fd[_index].handle == 0) || (poll_fd[_index].overlapped == NULL)) {
-			fds[i].revents |= POLLNVAL | POLLERR;
-			errno = EBADF;
-			if (_index >= 0) {
-				LeaveCriticalSection(&_poll_fd[_index].mutex);
-			}
-			usbi_warn(NULL, "invalid fd");
-			triggered = -1;
-			goto poll_exit;
-		}
-
-		// IN or OUT must match our fd direction
-		if ((fds[i].events & POLLIN) && (poll_fd[_index].rw != RW_READ)) {
-			fds[i].revents |= POLLNVAL | POLLERR;
-			errno = EBADF;
-			usbi_warn(NULL, "attempted POLLIN on fd without READ access");
-			LeaveCriticalSection(&_poll_fd[_index].mutex);
-			triggered = -1;
-			goto poll_exit;
-		}
-
-		if ((fds[i].events & POLLOUT) && (poll_fd[_index].rw != RW_WRITE)) {
-			fds[i].revents |= POLLNVAL | POLLERR;
-			errno = EBADF;
-			usbi_warn(NULL, "attempted POLLOUT on fd without WRITE access");
-			LeaveCriticalSection(&_poll_fd[_index].mutex);
-			triggered = -1;
-			goto poll_exit;
-		}
-
-		// The following macro only works if overlapped I/O was reported pending
-		if ( (HasOverlappedIoCompleted(poll_fd[_index].overlapped))
-		  || (HasOverlappedIoCompletedSync(poll_fd[_index].overlapped)) ) {
-			poll_dbg("  completed");
-			// checks above should ensure this works:
-			fds[i].revents = fds[i].events;
-			triggered++;
-		} else {
-			handles_to_wait_on[nb_handles_to_wait_on] = poll_fd[_index].overlapped->hEvent;
-			handle_to_index[nb_handles_to_wait_on] = i;
-#if defined(DYNAMIC_FDS)
-			// If this fd from the poll set is also part of the new_fd event handle table, remove it
-			usbi_mutex_lock(&new_fd_mutex);
-			for (j=0; j<nb_new_fds; j++) {
-				if (handles_to_wait_on[nb_handles_to_wait_on] == new_fd[j]) {
-					new_fd[j] = INVALID_HANDLE_VALUE;
-					break;
-				}
-			}
-			usbi_mutex_unlock(&new_fd_mutex);
-#endif
-			nb_handles_to_wait_on++;
-		}
-		LeaveCriticalSection(&_poll_fd[_index].mutex);
-	}
-#if defined(DYNAMIC_FDS)
-	// At this stage, new_fd[] should only contain events from fds that
-	// have been added since the last call to poll, but are not (yet) part
-	// of the pollable fd set. Typically, these would be from fds that have
-	// been created between the construction of the fd set and the calling
-	// of poll.
-	// Event if we won't be able to return usable poll data on these events,
-	// make sure we monitor them to return an EINTR code
-	usbi_mutex_lock(&new_fd_mutex); // We could probably do without
-	for (i=0; i<nb_new_fds; i++) {
-		if (new_fd[i] != INVALID_HANDLE_VALUE) {
-			handles_to_wait_on[nb_handles_to_wait_on++] = new_fd[i];
-			nb_extra_handles++;
-		}
-	}
-	usbi_mutex_unlock(&new_fd_mutex);
-	poll_dbg("dynamic_fds: added %d extra handles", nb_extra_handles);
-#endif
-
-	// If nothing was triggered, wait on all fds that require it
-	if ((timeout != 0) && (triggered == 0) && (nb_handles_to_wait_on != 0)) {
-#if defined(DYNAMIC_FDS)
-		// Register for fd update notifications
-		handles_to_wait_on[nb_handles_to_wait_on++] = fd_update;
-		nb_extra_handles++;
-#endif
-		if (timeout < 0) {
-			poll_dbg("starting infinite wait for %d handles...", (int)nb_handles_to_wait_on);
-		} else {
-			poll_dbg("starting %d ms wait for %d handles...", timeout, (int)nb_handles_to_wait_on);
-		}
-		ret = WaitForMultipleObjects(nb_handles_to_wait_on, handles_to_wait_on,
-			FALSE, (timeout<0)?INFINITE:(DWORD)timeout);
-		object_index = ret-WAIT_OBJECT_0;
-		if ((object_index >= 0) && ((DWORD)object_index < nb_handles_to_wait_on)) {
-#if defined(DYNAMIC_FDS)
-			if ((DWORD)object_index >= (nb_handles_to_wait_on-nb_extra_handles)) {
-				// Detected fd update => flag a poll interruption
-				if ((DWORD)object_index == (nb_handles_to_wait_on-1))
-					poll_dbg("  dynamic_fds: fd_update event");
-				else
-					poll_dbg("  dynamic_fds: new fd I/O event");
-				errno = EINTR;
-				triggered = -1;
-				goto poll_exit;
-			}
-#endif
-			poll_dbg("  completed after wait");
-			i = handle_to_index[object_index];
-			_index = _fd_to_index_and_lock(fds[i].fd);
-			fds[i].revents = fds[i].events;
-			triggered++;
-			if (_index >= 0) {
-				LeaveCriticalSection(&_poll_fd[_index].mutex);
-			}
-		} else if (ret == WAIT_TIMEOUT) {
-			poll_dbg("  timed out");
-			triggered = 0;	// 0 = timeout
-		} else {
-			errno = EIO;
-			triggered = -1;	// error
-		}
-	}
-
-poll_exit:
-	if (handles_to_wait_on != NULL) {
-		free(handles_to_wait_on);
-	}
-	if (handle_to_index != NULL) {
-		free(handle_to_index);
-	}
-#if defined(DYNAMIC_FDS)
-	usbi_mutex_lock(&new_fd_mutex);
-	nb_new_fds = 0;
-	usbi_mutex_unlock(&new_fd_mutex);
-#endif
-	return triggered;
-}
-
-/*
- * close a fake pipe fd
- */
-int usbi_close(int fd)
-{
-	int _index;
-	int r = -1;
-
-	CHECK_INIT_POLLING;
-
-	_index = _fd_to_index_and_lock(fd);
-
-	if (_index < 0) {
-		errno = EBADF;
-	} else {
-		if (poll_fd[_index].overlapped != NULL) {
-			// Must be a different event for each end of the pipe
-			CloseHandle(poll_fd[_index].overlapped->hEvent);
-			free(poll_fd[_index].overlapped);
-		}
-		r = _close(poll_fd[_index].fd);
-		if (r != 0) {
-			errno = EIO;
-		}
-		poll_fd[_index] = INVALID_WINFD;
-		LeaveCriticalSection(&_poll_fd[_index].mutex);
-	}
-	return r;
-}
-
-/*
- * synchronous write for fake "pipe" signaling
- */
-ssize_t usbi_write(int fd, const void *buf, size_t count)
-{
-	int _index;
-
-	CHECK_INIT_POLLING;
-
-	if (count != sizeof(unsigned char)) {
-		usbi_err(NULL, "this function should only used for signaling");
-		return -1;
-	}
-
-	_index = _fd_to_index_and_lock(fd);
-
-	if ( (_index < 0) || (poll_fd[_index].overlapped == NULL) ) {
-		errno = EBADF;
-		if (_index >= 0) {
-			LeaveCriticalSection(&_poll_fd[_index].mutex);
-		}
-		return -1;
-	}
-
-	poll_dbg("set pipe event (fd = %d, thread = %08X)", _index, GetCurrentThreadId());
-	SetEvent(poll_fd[_index].overlapped->hEvent);
-	poll_fd[_index].overlapped->Internal = STATUS_WAIT_0;
-	// If two threads write on the pipe at the same time, we need to
-	// process two separate reads => use the overlapped as a counter
-	poll_fd[_index].overlapped->InternalHigh++;
-
-	LeaveCriticalSection(&_poll_fd[_index].mutex);
-	return sizeof(unsigned char);
-}
-
-/*
- * synchronous read for fake "pipe" signaling
- */
-ssize_t usbi_read(int fd, void *buf, size_t count)
-{
-	int _index;
-	ssize_t r = -1;
-
-	CHECK_INIT_POLLING;
-
-	if (count != sizeof(unsigned char)) {
-		usbi_err(NULL, "this function should only used for signaling");
-		return -1;
-	}
-
-	_index = _fd_to_index_and_lock(fd);
-
-	if (_index < 0) {
-		errno = EBADF;
-		return -1;
-	}
-
-	if (WaitForSingleObject(poll_fd[_index].overlapped->hEvent, INFINITE) != WAIT_OBJECT_0) {
-		usbi_warn(NULL, "waiting for event failed: %d", (int)GetLastError());
-		errno = EIO;
-		goto out;
-	}
-
-	poll_dbg("clr pipe event (fd = %d, thread = %08X)", _index, GetCurrentThreadId());
-	poll_fd[_index].overlapped->InternalHigh--;
-	// Don't reset unless we don't have any more events to process
-	if (poll_fd[_index].overlapped->InternalHigh <= 0) {
-		ResetEvent(poll_fd[_index].overlapped->hEvent);
-		poll_fd[_index].overlapped->Internal = STATUS_PENDING;
-	}
-
-	r = sizeof(unsigned char);
-
-out:
-	LeaveCriticalSection(&_poll_fd[_index].mutex);
-	return r;
-}
diff --git a/third_party/libusb/libusb/os/poll_windows.h b/third_party/libusb/libusb/os/poll_windows.h
deleted file mode 100644
index 27986b8..0000000
--- a/third_party/libusb/libusb/os/poll_windows.h
+++ /dev/null
@@ -1,118 +0,0 @@
-/*
- * Windows compat: POSIX compatibility wrapper
- * Copyright (C) 2009-2010 Pete Batard <pbatard@gmail.com>
- * With contributions from Michael Plante, Orin Eman et al.
- * Parts of poll implementation from libusb-win32, by Stephan Meyer et al.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- *
- */
-
-#ifndef LIBUSB_POLL_WINDOWS_H
-#define LIBUSB_POLL_WINDOWS_H
-#pragma once
-
-#if defined(_MSC_VER)
-// disable /W4 MSVC warnings that are benign
-#pragma warning(disable:4127) // conditional expression is constant
-#endif
-
-// Uncomment to have poll return with EINTR as soon as a new transfer (fd) is added
-// This should result in a LIBUSB_ERROR_INTERRUPTED being returned by libusb calls,
-// which should give the app an opportunity to resubmit a new fd set.
-//#define DYNAMIC_FDS
-
-// Handle synchronous completion through the overlapped structure
-#if !defined(STATUS_REPARSE)	// reuse the REPARSE status code
-#define STATUS_REPARSE ((LONG)0x00000104L)
-#endif
-#define STATUS_COMPLETED_SYNCHRONOUSLY	STATUS_REPARSE
-#define HasOverlappedIoCompletedSync(lpOverlapped)	(((DWORD)(lpOverlapped)->Internal) == STATUS_COMPLETED_SYNCHRONOUSLY)
-
-#define DUMMY_HANDLE ((HANDLE)(LONG_PTR)-2)
-
-enum windows_version {
-	WINDOWS_UNSUPPORTED,
-	WINDOWS_XP,
-	WINDOWS_2003,	// also includes XP 64
-	WINDOWS_VISTA_AND_LATER,
-};
-extern enum windows_version windows_version;
-
-#define MAX_FDS     256
-
-#define POLLIN      0x0001    /* There is data to read */
-#define POLLPRI     0x0002    /* There is urgent data to read */
-#define POLLOUT     0x0004    /* Writing now will not block */
-#define POLLERR     0x0008    /* Error condition */
-#define POLLHUP     0x0010    /* Hung up */
-#define POLLNVAL    0x0020    /* Invalid request: fd not open */
-
-// access modes
-enum rw_type {
-	RW_NONE,
-	RW_READ,
-	RW_WRITE,
-};
-
-// fd struct that can be used for polling on Windows
-struct winfd {
-	int fd;							// what's exposed to libusb core
-	HANDLE handle;					// what we need to attach overlapped to the I/O op, so we can poll it
-	OVERLAPPED* overlapped;			// what will report our I/O status
-	enum rw_type rw;				// I/O transfer direction: read *XOR* write (NOT BOTH)
-};
-extern const struct winfd INVALID_WINFD;
-
-int usbi_pipe(int pipefd[2]);
-int usbi_poll(struct pollfd *fds, unsigned int nfds, int timeout);
-ssize_t usbi_write(int fd, const void *buf, size_t count);
-ssize_t usbi_read(int fd, void *buf, size_t count);
-int usbi_close(int fd);
-
-void init_polling(void);
-void exit_polling(void);
-struct winfd usbi_create_fd(HANDLE handle, int access_mode);
-void usbi_free_fd(int fd);
-struct winfd fd_to_winfd(int fd);
-struct winfd handle_to_winfd(HANDLE handle);
-struct winfd overlapped_to_winfd(OVERLAPPED* overlapped);
-
-/*
- * Timeval operations
- */
-#if defined(DDKBUILD)
-#include <winsock.h>	// defines timeval functions on DDK
-#endif
-
-#if !defined(TIMESPEC_TO_TIMEVAL)
-#define TIMESPEC_TO_TIMEVAL(tv, ts) {                   \
-	(tv)->tv_sec = (long)(ts)->tv_sec;                  \
-	(tv)->tv_usec = (long)(ts)->tv_nsec / 1000;         \
-}
-#endif
-#if !defined(timersub)
-#define timersub(a, b, result)                          \
-do {                                                    \
-	(result)->tv_sec = (a)->tv_sec - (b)->tv_sec;       \
-	(result)->tv_usec = (a)->tv_usec - (b)->tv_usec;    \
-	if ((result)->tv_usec < 0) {                        \
-		--(result)->tv_sec;                             \
-		(result)->tv_usec += 1000000;                   \
-	}                                                   \
-} while (0)
-#endif
-
-#endif /* LIBUSB_POLL_WINDOWS_H */
diff --git a/third_party/libusb/libusb/os/threads_posix.c b/third_party/libusb/libusb/os/threads_posix.c
deleted file mode 100644
index 435b873..0000000
--- a/third_party/libusb/libusb/os/threads_posix.c
+++ /dev/null
@@ -1,55 +0,0 @@
-/*
- * libusb synchronization using POSIX Threads
- *
- * Copyright (C) 2011 Vitali Lovich <vlovich@aliph.com>
- * Copyright (C) 2011 Peter Stuge <peter@stuge.se>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#ifdef _XOPEN_SOURCE
-# if _XOPEN_SOURCE < 500
-#  undef _XOPEN_SOURCE
-#  define _XOPEN_SOURCE 500
-# endif
-#else
-#define _XOPEN_SOURCE 500
-#endif /* _XOPEN_SOURCE */
-
-#include <pthread.h>
-
-int usbi_mutex_init_recursive(pthread_mutex_t *mutex, pthread_mutexattr_t *attr)
-{
-	int err;
-	pthread_mutexattr_t stack_attr;
-	if (!attr) {
-		attr = &stack_attr;
-		err = pthread_mutexattr_init(&stack_attr);
-		if (err != 0)
-			return err;
-	}
-
-	err = pthread_mutexattr_settype(attr, PTHREAD_MUTEX_RECURSIVE);
-	if (err != 0)
-		goto finish;
-
-	err = pthread_mutex_init(mutex, attr);
-
-finish:
-	if (attr == &stack_attr)
-		pthread_mutexattr_destroy(&stack_attr);
-
-	return err;
-}
diff --git a/third_party/libusb/libusb/os/threads_posix.h b/third_party/libusb/libusb/os/threads_posix.h
deleted file mode 100644
index 9752208..0000000
--- a/third_party/libusb/libusb/os/threads_posix.h
+++ /dev/null
@@ -1,48 +0,0 @@
-/*
- * libusb synchronization using POSIX Threads
- *
- * Copyright (C) 2010 Peter Stuge <peter@stuge.se>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#ifndef LIBUSB_THREADS_POSIX_H
-#define LIBUSB_THREADS_POSIX_H
-
-#include <pthread.h>
-
-#define usbi_mutex_static_t		pthread_mutex_t
-#define USBI_MUTEX_INITIALIZER		PTHREAD_MUTEX_INITIALIZER
-#define usbi_mutex_static_lock		pthread_mutex_lock
-#define usbi_mutex_static_unlock	pthread_mutex_unlock
-
-#define usbi_mutex_t			pthread_mutex_t
-#define usbi_mutex_init			pthread_mutex_init
-#define usbi_mutex_lock			pthread_mutex_lock
-#define usbi_mutex_unlock		pthread_mutex_unlock
-#define usbi_mutex_trylock		pthread_mutex_trylock
-#define usbi_mutex_destroy		pthread_mutex_destroy
-
-#define usbi_cond_t			pthread_cond_t
-#define usbi_cond_init			pthread_cond_init
-#define usbi_cond_wait			pthread_cond_wait
-#define usbi_cond_timedwait		pthread_cond_timedwait
-#define usbi_cond_broadcast		pthread_cond_broadcast
-#define usbi_cond_destroy		pthread_cond_destroy
-#define usbi_cond_signal		pthread_cond_signal
-
-extern int usbi_mutex_init_recursive(pthread_mutex_t *mutex, pthread_mutexattr_t *attr);
-
-#endif /* LIBUSB_THREADS_POSIX_H */
diff --git a/third_party/libusb/libusb/os/threads_windows.c b/third_party/libusb/libusb/os/threads_windows.c
deleted file mode 100644
index 8a29920..0000000
--- a/third_party/libusb/libusb/os/threads_windows.c
+++ /dev/null
@@ -1,208 +0,0 @@
-/*
- * libusb synchronization on Microsoft Windows
- *
- * Copyright (C) 2010 Michael Plante <michael.plante@gmail.com>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#include <config.h>
-#include <objbase.h>
-#include <errno.h>
-#include <stdarg.h>
-
-#include "libusbi.h"
-
-
-int usbi_mutex_init(usbi_mutex_t *mutex,
-					const usbi_mutexattr_t *attr) {
-	if(! mutex) return ((errno=EINVAL));
-	*mutex = CreateMutex(NULL, FALSE, NULL);
-	if(!*mutex) return ((errno=ENOMEM));
-	return 0;
-}
-int usbi_mutex_destroy(usbi_mutex_t *mutex) {
-	// It is not clear if CloseHandle failure is due to failure to unlock.
-	//   If so, this should be errno=EBUSY.
-	if(!mutex || !CloseHandle(*mutex)) return ((errno=EINVAL));
-	*mutex = NULL;
-	return 0;
-}
-int usbi_mutex_trylock(usbi_mutex_t *mutex) {
-	DWORD result;
-	if(!mutex) return ((errno=EINVAL));
-	result = WaitForSingleObject(*mutex, 0);
-	if(result == WAIT_OBJECT_0 || result == WAIT_ABANDONED)
-		return 0; // acquired (ToDo: check that abandoned is ok)
-	if(result == WAIT_TIMEOUT)
-		return ((errno=EBUSY));
-	return ((errno=EINVAL)); // don't know how this would happen
-							 //   so don't know proper errno
-}
-int usbi_mutex_lock(usbi_mutex_t *mutex) {
-	DWORD result;
-	if(!mutex) return ((errno=EINVAL));
-	result = WaitForSingleObject(*mutex, INFINITE);
-	if(result == WAIT_OBJECT_0 || result == WAIT_ABANDONED)
-		return 0; // acquired (ToDo: check that abandoned is ok)
-	return ((errno=EINVAL)); // don't know how this would happen
-							 //   so don't know proper errno
-}
-int usbi_mutex_unlock(usbi_mutex_t *mutex) {
-	if(!mutex)                return ((errno=EINVAL));
-	if(!ReleaseMutex(*mutex)) return ((errno=EPERM ));
-	return 0;
-}
-
-int usbi_mutex_static_lock(usbi_mutex_static_t *mutex) {
-	if(!mutex)               return ((errno=EINVAL));
-	while (InterlockedExchange((LONG *)mutex, 1) == 1) {
-		SleepEx(0, TRUE);
-	}
-	return 0;
-}
-int usbi_mutex_static_unlock(usbi_mutex_static_t *mutex) {
-	if(!mutex)               return ((errno=EINVAL));
-	*mutex = 0;
-	return 0;
-}
-
-
-
-int usbi_cond_init(usbi_cond_t *cond,
-				   const usbi_condattr_t *attr) {
-	if(!cond)           return ((errno=EINVAL));
-	list_init(&cond->waiters    );
-	list_init(&cond->not_waiting);
-	return 0;
-}
-int usbi_cond_destroy(usbi_cond_t *cond) {
-	// This assumes no one is using this anymore.  The check MAY NOT BE safe.
-	struct usbi_cond_perthread *pos, *prev_pos = NULL;
-	if(!cond) return ((errno=EINVAL));
-	if(!list_empty(&cond->waiters)) return ((errno=EBUSY )); // (!see above!)
-	list_for_each_entry(pos, &cond->not_waiting, list, struct usbi_cond_perthread) {
-		free(prev_pos);
-		list_del(&pos->list);
-		prev_pos = pos;
-	}
-	free(prev_pos);
-	prev_pos = pos = NULL;
-
-	return 0;
-}
-
-int usbi_cond_broadcast(usbi_cond_t *cond) {
-	// Assumes mutex is locked; this is not in keeping with POSIX spec, but
-	//   libusb does this anyway, so we simplify by not adding more sync
-	//   primitives to the CV definition!
-	int fail = 0;
-	struct usbi_cond_perthread *pos;
-	if(!cond)                      return ((errno=EINVAL));
-	list_for_each_entry(pos, &cond->waiters, list, struct usbi_cond_perthread) {
-		if(!SetEvent(pos->event))
-			fail = 1;
-	}
-	// The wait function will remove its respective item from the list.
-	return fail ? ((errno=EINVAL)) : 0;
-}
-int usbi_cond_signal(usbi_cond_t *cond) {
-	// Assumes mutex is locked; this is not in keeping with POSIX spec, but
-	//   libusb does this anyway, so we simplify by not adding more sync
-	//   primitives to the CV definition!
-	struct usbi_cond_perthread *pos;
-	if(!cond)                      return ((errno=EINVAL));
-	if(list_empty(&cond->waiters)) return 0; // no one to wakeup.
-	pos = list_entry(&cond->waiters.next, struct usbi_cond_perthread, list);
-	// The wait function will remove its respective item from the list.
-	return SetEvent(pos->event) ? 0 : ((errno=EINVAL));
-}
-static int __inline usbi_cond_intwait(usbi_cond_t *cond,
-									  usbi_mutex_t *mutex,
-									  DWORD timeout_ms) {
-	struct usbi_cond_perthread *pos;
-	int found = 0, r;
-	DWORD r2,tid = GetCurrentThreadId();
-	if(!cond || !mutex) return ((errno=EINVAL));
-	list_for_each_entry(pos, &cond->not_waiting, list, struct usbi_cond_perthread) {
-		if(tid == pos->tid) {
-			found = 1;
-			break;
-		}
-	}
-	if(!found) {
-		pos      = malloc(sizeof(struct usbi_cond_perthread));
-		if(!pos) return ((errno=ENOMEM)); // This errno is not POSIX-allowed.
-		pos->tid = tid;
-		pos->event = CreateEvent(NULL, FALSE, FALSE, NULL); // auto-reset.
-		if(!pos->event) {
-			free(pos);
-			return      ((errno=ENOMEM));
-		}
-		list_add(&pos->list, &cond->not_waiting);
-	}
-
-	list_del(&pos->list); // remove from not_waiting list.
-	list_add(&pos->list, &cond->waiters);
-
-	r  = usbi_mutex_unlock(mutex);
-	if(r) return r;
-	r2 = WaitForSingleObject(pos->event, timeout_ms);
-	r  = usbi_mutex_lock(mutex);
-	if(r) return r;
-
-	list_del(&pos->list);
-	list_add(&pos->list, &cond->not_waiting);
-
-	if(r2 == WAIT_TIMEOUT) return ((errno=ETIMEDOUT));
-
-	return 0;
-}
-// N.B.: usbi_cond_*wait() can also return ENOMEM, even though pthread_cond_*wait cannot!
-int usbi_cond_wait(usbi_cond_t *cond, usbi_mutex_t *mutex) {
-	return usbi_cond_intwait(cond, mutex, INFINITE);
-}
-int usbi_cond_timedwait(usbi_cond_t *cond,
-						usbi_mutex_t *mutex,
-						const struct timespec *abstime) {
-	FILETIME filetime;
-	ULARGE_INTEGER rtime;
-	struct timeval targ_time, cur_time, delta_time;
-	struct timespec cur_time_ns;
-	DWORD millis;
-	extern const uint64_t epoch_time;
-
-	GetSystemTimeAsFileTime(&filetime);
-	rtime.LowPart   = filetime.dwLowDateTime;
-	rtime.HighPart  = filetime.dwHighDateTime;
-	rtime.QuadPart -= epoch_time;
-	cur_time_ns.tv_sec = (long)(rtime.QuadPart / 10000000);
-	cur_time_ns.tv_nsec = (long)((rtime.QuadPart % 10000000)*100);
-	TIMESPEC_TO_TIMEVAL(&cur_time, &cur_time_ns);
-
-	TIMESPEC_TO_TIMEVAL(&targ_time, abstime);
-	timersub(&targ_time, &cur_time, &delta_time);
-	if(delta_time.tv_sec < 0) // abstime already passed?
-		millis = 0;
-	else {
-		millis  = delta_time.tv_usec/1000;
-		millis += delta_time.tv_sec *1000;
-		if (delta_time.tv_usec % 1000) // round up to next millisecond
-			millis++;
-	}
-
-	return usbi_cond_intwait(cond, mutex, millis);
-}
-
diff --git a/third_party/libusb/libusb/os/threads_windows.h b/third_party/libusb/libusb/os/threads_windows.h
deleted file mode 100644
index 7bb144a..0000000
--- a/third_party/libusb/libusb/os/threads_windows.h
+++ /dev/null
@@ -1,86 +0,0 @@
-/*
- * libusb synchronization on Microsoft Windows
- *
- * Copyright (C) 2010 Michael Plante <michael.plante@gmail.com>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#ifndef LIBUSB_THREADS_WINDOWS_H
-#define LIBUSB_THREADS_WINDOWS_H
-
-#define usbi_mutex_static_t     volatile LONG
-#define USBI_MUTEX_INITIALIZER  0
-
-#define usbi_mutex_t            HANDLE
-
-struct usbi_cond_perthread {
-	struct list_head list;
-	DWORD            tid;
-	HANDLE           event;
-};
-struct usbi_cond_t_ {
-	// Every time a thread touches the CV, it winds up in one of these lists.
-	//   It stays there until the CV is destroyed, even if the thread
-	//   terminates.
-	struct list_head waiters;
-	struct list_head not_waiting;
-};
-typedef struct usbi_cond_t_ usbi_cond_t;
-
-// We *were* getting timespec from pthread.h:
-#if (!defined(HAVE_STRUCT_TIMESPEC) && !defined(_TIMESPEC_DEFINED))
-#define HAVE_STRUCT_TIMESPEC 1
-#define _TIMESPEC_DEFINED 1
-struct timespec {
-		long tv_sec;
-		long tv_nsec;
-};
-#endif /* HAVE_STRUCT_TIMESPEC | _TIMESPEC_DEFINED */
-
-// We *were* getting ETIMEDOUT from pthread.h:
-#ifndef ETIMEDOUT
-#  define ETIMEDOUT 10060     /* This is the value in winsock.h. */
-#endif
-
-#define usbi_mutexattr_t void
-#define usbi_condattr_t  void
-
-// all Windows mutexes are recursive
-#define usbi_mutex_init_recursive(mutex, attr) usbi_mutex_init((mutex), (attr))
-
-int usbi_mutex_static_lock(usbi_mutex_static_t *mutex);
-int usbi_mutex_static_unlock(usbi_mutex_static_t *mutex);
-
-
-int usbi_mutex_init(usbi_mutex_t *mutex,
-					const usbi_mutexattr_t *attr);
-int usbi_mutex_lock(usbi_mutex_t *mutex);
-int usbi_mutex_unlock(usbi_mutex_t *mutex);
-int usbi_mutex_trylock(usbi_mutex_t *mutex);
-int usbi_mutex_destroy(usbi_mutex_t *mutex);
-
-int usbi_cond_init(usbi_cond_t *cond,
-				   const usbi_condattr_t *attr);
-int usbi_cond_destroy(usbi_cond_t *cond);
-int usbi_cond_wait(usbi_cond_t *cond, usbi_mutex_t *mutex);
-int usbi_cond_timedwait(usbi_cond_t *cond,
-						usbi_mutex_t *mutex,
-						const struct timespec *abstime);
-int usbi_cond_broadcast(usbi_cond_t *cond);
-int usbi_cond_signal(usbi_cond_t *cond);
-
-#endif /* LIBUSB_THREADS_WINDOWS_H */
-
diff --git a/third_party/libusb/libusb/os/windows_usb.c b/third_party/libusb/libusb/os/windows_usb.c
deleted file mode 100644
index 68216db..0000000
--- a/third_party/libusb/libusb/os/windows_usb.c
+++ /dev/null
@@ -1,3038 +0,0 @@
-/*
- * windows backend for libusb 1.0
- * Copyright (c) 2009-2010 Pete Batard <pbatard@gmail.com>
- * With contributions from Michael Plante, Orin Eman et al.
- * Parts of this code adapted from libusb-win32-v1 by Stephan Meyer
- * Hash table functions adapted from glibc, by Ulrich Drepper et al.
- * Major code testing contribution by Xiaofan Chen
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-// COMPILATION OPTIONS:
-// - Should libusb automatically claim (and release) the interfaces it requires?
-#define AUTO_CLAIM
-// - Forces instant overlapped completion on timeouts: can prevents extensive
-//   wait in poll, after a timeout, but might affect subsequent API calls.
-//   ***USE AT YOUR OWN RISKS***
-//#define FORCE_INSTANT_TIMEOUTS
-
-#include <config.h>
-#include <windows.h>
-#include <setupapi.h>
-#include <ctype.h>
-#include <errno.h>
-#include <fcntl.h>
-#include <process.h>
-#include <stdio.h>
-#include <inttypes.h>
-#include <objbase.h>
-#include <winioctl.h>
-
-#include <libusbi.h>
-#include "poll_windows.h"
-#include "windows_usb.h"
-
-// The following prevents "banned API" errors when using the MS's WDK OACR/Prefast
-#if defined(_PREFAST_)
-#pragma warning(disable:28719)
-#endif
-
-// The 2 macros below are used in conjunction with safe loops.
-#define LOOP_CHECK(fcall) { r=fcall; if (r != LIBUSB_SUCCESS) continue; }
-#define LOOP_BREAK(err) { r=err; continue; }
-
-extern void usbi_fd_notification(struct libusb_context *ctx);
-
-// Helper prototypes
-static int windows_get_active_config_descriptor(struct libusb_device *dev, unsigned char *buffer, size_t len, int *host_endian);
-static int windows_clock_gettime(int clk_id, struct timespec *tp);
-unsigned __stdcall windows_clock_gettime_threaded(void* param);
-// WinUSB API prototypes
-static int winusb_init(struct libusb_context *ctx);
-static int winusb_exit(void);
-static int winusb_open(struct libusb_device_handle *dev_handle);
-static void winusb_close(struct libusb_device_handle *dev_handle);
-static int winusb_configure_endpoints(struct libusb_device_handle *dev_handle, int iface);
-static int winusb_claim_interface(struct libusb_device_handle *dev_handle, int iface);
-static int winusb_release_interface(struct libusb_device_handle *dev_handle, int iface);
-static int winusb_submit_control_transfer(struct usbi_transfer *itransfer);
-static int winusb_set_interface_altsetting(struct libusb_device_handle *dev_handle, int iface, int altsetting);
-static int winusb_submit_bulk_transfer(struct usbi_transfer *itransfer);
-static int winusb_clear_halt(struct libusb_device_handle *dev_handle, unsigned char endpoint);
-static int winusb_abort_transfers(struct usbi_transfer *itransfer);
-static int winusb_abort_control(struct usbi_transfer *itransfer);
-static int winusb_reset_device(struct libusb_device_handle *dev_handle);
-static int winusb_copy_transfer_data(struct usbi_transfer *itransfer, uint32_t io_size);
-// Composite API prototypes
-static int composite_init(struct libusb_context *ctx);
-static int composite_exit(void);
-static int composite_open(struct libusb_device_handle *dev_handle);
-static void composite_close(struct libusb_device_handle *dev_handle);
-static int composite_claim_interface(struct libusb_device_handle *dev_handle, int iface);
-static int composite_set_interface_altsetting(struct libusb_device_handle *dev_handle, int iface, int altsetting);
-static int composite_release_interface(struct libusb_device_handle *dev_handle, int iface);
-static int composite_submit_control_transfer(struct usbi_transfer *itransfer);
-static int composite_submit_bulk_transfer(struct usbi_transfer *itransfer);
-static int composite_submit_iso_transfer(struct usbi_transfer *itransfer);
-static int composite_clear_halt(struct libusb_device_handle *dev_handle, unsigned char endpoint);
-static int composite_abort_transfers(struct usbi_transfer *itransfer);
-static int composite_abort_control(struct usbi_transfer *itransfer);
-static int composite_reset_device(struct libusb_device_handle *dev_handle);
-static int composite_copy_transfer_data(struct usbi_transfer *itransfer, uint32_t io_size);
-
-
-// Global variables
-uint64_t hires_frequency, hires_ticks_to_ps;
-const uint64_t epoch_time = UINT64_C(116444736000000000);	// 1970.01.01 00:00:000 in MS Filetime
-enum windows_version windows_version = WINDOWS_UNSUPPORTED;
-// Concurrency
-static int concurrent_usage = -1;
-#if defined(AUTO_CLAIM)
-usbi_mutex_t autoclaim_lock;
-#endif
-// Timer thread
-// NB: index 0 is for monotonic and 1 is for the thread exit event
-HANDLE timer_thread = NULL;
-HANDLE timer_mutex = NULL;
-struct timespec timer_tp;
-volatile LONG request_count[2] = {0, 1};	// last one must be > 0
-HANDLE timer_request[2] = { NULL, NULL };
-HANDLE timer_response = NULL;
-// API globals
-bool api_winusb_available = false;
-#define CHECK_WINUSB_AVAILABLE do { if (!api_winusb_available) return LIBUSB_ERROR_ACCESS; } while (0)
-
-static inline BOOLEAN guid_eq(const GUID *guid1, const GUID *guid2) {
-	if ((guid1 != NULL) && (guid2 != NULL)) {
-		return (memcmp(guid1, guid2, sizeof(GUID)) == 0);
-	}
-	return false;
-}
-
-#if defined(ENABLE_DEBUG_LOGGING)
-static char* guid_to_string(const GUID* guid)
-{
-	static char guid_string[MAX_GUID_STRING_LENGTH];
-
-	if (guid == NULL) return NULL;
-	sprintf(guid_string, "{%08X-%04X-%04X-%02X%02X-%02X%02X%02X%02X%02X%02X}",
-		(unsigned int)guid->Data1, guid->Data2, guid->Data3,
-		guid->Data4[0], guid->Data4[1], guid->Data4[2], guid->Data4[3],
-		guid->Data4[4], guid->Data4[5], guid->Data4[6], guid->Data4[7]);
-	return guid_string;
-}
-#endif
-
-/*
- * Converts a windows error to human readable string
- * uses retval as errorcode, or, if 0, use GetLastError()
- */
-#if defined(ENABLE_LOGGING)
-static char *windows_error_str(uint32_t retval)
-{
-static char err_string[ERR_BUFFER_SIZE];
-
-	DWORD size;
-	size_t i;
-	uint32_t error_code, format_error;
-
-	error_code = retval?retval:GetLastError();
-
-	safe_sprintf(err_string, ERR_BUFFER_SIZE, "[%d] ", error_code);
-
-	size = FormatMessageA(FORMAT_MESSAGE_FROM_SYSTEM, NULL, error_code,
-		MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), &err_string[safe_strlen(err_string)],
-		ERR_BUFFER_SIZE - (DWORD)safe_strlen(err_string), NULL);
-	if (size == 0) {
-		format_error = GetLastError();
-		if (format_error)
-			safe_sprintf(err_string, ERR_BUFFER_SIZE,
-				"Windows error code %u (FormatMessage error code %u)", error_code, format_error);
-		else
-			safe_sprintf(err_string, ERR_BUFFER_SIZE, "Unknown error code %u", error_code);
-	} else {
-		// Remove CR/LF terminators
-		for (i=safe_strlen(err_string)-1; ((err_string[i]==0x0A) || (err_string[i]==0x0D)); i--) {
-			err_string[i] = 0;
-		}
-	}
-	return err_string;
-}
-#endif
-
-/*
- * Sanitize Microsoft's paths: convert to uppercase, add prefix and fix backslashes.
- * Return an allocated sanitized string or NULL on error.
- */
-static char* sanitize_path(const char* path)
-{
-	const char root_prefix[] = "\\\\.\\";
-	size_t j, size, root_size;
-	char* ret_path = NULL;
-	size_t add_root = 0;
-
-	if (path == NULL)
-		return NULL;
-
-	size = safe_strlen(path)+1;
-	root_size = sizeof(root_prefix)-1;
-
-	// Microsoft indiscriminatly uses '\\?\', '\\.\', '##?#" or "##.#" for root prefixes.
-	if (!((size > 3) && (((path[0] == '\\') && (path[1] == '\\') && (path[3] == '\\')) ||
-		((path[0] == '#') && (path[1] == '#') && (path[3] == '#'))))) {
-		add_root = root_size;
-		size += add_root;
-	}
-
-	if ((ret_path = (char*)calloc(size, 1)) == NULL)
-		return NULL;
-
-	safe_strcpy(&ret_path[add_root], size-add_root, path);
-
-	// Ensure consistancy with root prefix
-	for (j=0; j<root_size; j++)
-		ret_path[j] = root_prefix[j];
-
-	// Same goes for '\' and '#' after the root prefix. Ensure '#' is used
-	for(j=root_size; j<size; j++) {
-		ret_path[j] = (char)toupper((int)ret_path[j]);	// Fix case too
-		if (ret_path[j] == '\\')
-			ret_path[j] = '#';
-	}
-
-	return ret_path;
-}
-
-/*
- * Cfgmgr32, OLE32 and SetupAPI DLL functions
- */
-static int init_dlls(void)
-{
-	DLL_LOAD(Cfgmgr32.dll, CM_Get_Parent, TRUE);
-	DLL_LOAD(Cfgmgr32.dll, CM_Get_Child, TRUE);
-	DLL_LOAD(Cfgmgr32.dll, CM_Get_Sibling, TRUE);
-	DLL_LOAD(Cfgmgr32.dll, CM_Get_Device_IDA, TRUE);
-	// Prefixed to avoid conflict with header files
-	DLL_LOAD_PREFIXED(OLE32.dll, p, CLSIDFromString, TRUE);
-	DLL_LOAD_PREFIXED(SetupAPI.dll, p, SetupDiGetClassDevsA, TRUE);
-	DLL_LOAD_PREFIXED(SetupAPI.dll, p, SetupDiEnumDeviceInfo, TRUE);
-	DLL_LOAD_PREFIXED(SetupAPI.dll, p, SetupDiEnumDeviceInterfaces, TRUE);
-	DLL_LOAD_PREFIXED(SetupAPI.dll, p, SetupDiGetDeviceInterfaceDetailA, TRUE);
-	DLL_LOAD_PREFIXED(SetupAPI.dll, p, SetupDiDestroyDeviceInfoList, TRUE);
-	DLL_LOAD_PREFIXED(SetupAPI.dll, p, SetupDiOpenDevRegKey, TRUE);
-	DLL_LOAD_PREFIXED(SetupAPI.dll, p, SetupDiGetDeviceRegistryPropertyA, TRUE);
-	DLL_LOAD_PREFIXED(AdvAPI32.dll, p, RegQueryValueExW, TRUE);
-	DLL_LOAD_PREFIXED(AdvAPI32.dll, p, RegCloseKey, TRUE);
-	return LIBUSB_SUCCESS;
-}
-
-/*
- * enumerate interfaces for the whole USB class
- *
- * Parameters:
- * dev_info: a pointer to a dev_info list
- * dev_info_data: a pointer to an SP_DEVINFO_DATA to be filled (or NULL if not needed)
- * usb_class: the generic USB class for which to retrieve interface details
- * index: zero based index of the interface in the device info list
- *
- * Note: it is the responsibility of the caller to free the DEVICE_INTERFACE_DETAIL_DATA
- * structure returned and call this function repeatedly using the same guid (with an
- * incremented index starting at zero) until all interfaces have been returned.
- */
-static bool get_devinfo_data(struct libusb_context *ctx,
-	HDEVINFO *dev_info, SP_DEVINFO_DATA *dev_info_data, char* usb_class, unsigned _index)
-{
-	if (_index <= 0) {
-		*dev_info = pSetupDiGetClassDevsA(NULL, usb_class, NULL, DIGCF_PRESENT|DIGCF_ALLCLASSES);
-		if (*dev_info == INVALID_HANDLE_VALUE) {
-			return false;
-		}
-	}
-
-	dev_info_data->cbSize = sizeof(SP_DEVINFO_DATA);
-	if (!pSetupDiEnumDeviceInfo(*dev_info, _index, dev_info_data)) {
-		if (GetLastError() != ERROR_NO_MORE_ITEMS) {
-			usbi_err(ctx, "Could not obtain device info data for index %u: %s",
-				_index, windows_error_str(0));
-		}
-		pSetupDiDestroyDeviceInfoList(*dev_info);
-		*dev_info = INVALID_HANDLE_VALUE;
-		return false;
-	}
-	return true;
-}
-
-/*
- * enumerate interfaces for a specific GUID
- *
- * Parameters:
- * dev_info: a pointer to a dev_info list
- * dev_info_data: a pointer to an SP_DEVINFO_DATA to be filled (or NULL if not needed)
- * guid: the GUID for which to retrieve interface details
- * index: zero based index of the interface in the device info list
- *
- * Note: it is the responsibility of the caller to free the DEVICE_INTERFACE_DETAIL_DATA
- * structure returned and call this function repeatedly using the same guid (with an
- * incremented index starting at zero) until all interfaces have been returned.
- */
-static SP_DEVICE_INTERFACE_DETAIL_DATA_A *get_interface_details(struct libusb_context *ctx,
-	HDEVINFO *dev_info, SP_DEVINFO_DATA *dev_info_data, const GUID* guid, unsigned _index)
-{
-	SP_DEVICE_INTERFACE_DATA dev_interface_data;
-	SP_DEVICE_INTERFACE_DETAIL_DATA_A *dev_interface_details = NULL;
-	DWORD size;
-
-	if (_index <= 0) {
-		*dev_info = pSetupDiGetClassDevsA(guid, NULL, NULL, DIGCF_PRESENT|DIGCF_DEVICEINTERFACE);
-	}
-
-	if (dev_info_data != NULL) {
-		dev_info_data->cbSize = sizeof(SP_DEVINFO_DATA);
-		if (!pSetupDiEnumDeviceInfo(*dev_info, _index, dev_info_data)) {
-			if (GetLastError() != ERROR_NO_MORE_ITEMS) {
-				usbi_err(ctx, "Could not obtain device info data for index %u: %s",
-					_index, windows_error_str(0));
-			}
-			pSetupDiDestroyDeviceInfoList(*dev_info);
-			*dev_info = INVALID_HANDLE_VALUE;
-			return NULL;
-		}
-	}
-
-	dev_interface_data.cbSize = sizeof(SP_DEVICE_INTERFACE_DATA);
-	if (!pSetupDiEnumDeviceInterfaces(*dev_info, NULL, guid, _index, &dev_interface_data)) {
-		if (GetLastError() != ERROR_NO_MORE_ITEMS) {
-			usbi_err(ctx, "Could not obtain interface data for index %u: %s",
-				_index, windows_error_str(0));
-		}
-		pSetupDiDestroyDeviceInfoList(*dev_info);
-		*dev_info = INVALID_HANDLE_VALUE;
-		return NULL;
-	}
-
-	// Read interface data (dummy + actual) to access the device path
-	if (!pSetupDiGetDeviceInterfaceDetailA(*dev_info, &dev_interface_data, NULL, 0, &size, NULL)) {
-		// The dummy call should fail with ERROR_INSUFFICIENT_BUFFER
-		if (GetLastError() != ERROR_INSUFFICIENT_BUFFER) {
-			usbi_err(ctx, "could not access interface data (dummy) for index %u: %s",
-				_index, windows_error_str(0));
-			goto err_exit;
-		}
-	} else {
-		usbi_err(ctx, "program assertion failed - http://msdn.microsoft.com/en-us/library/ms792901.aspx is wrong.");
-		goto err_exit;
-	}
-
-	if ((dev_interface_details = malloc(size)) == NULL) {
-		usbi_err(ctx, "could not allocate interface data for index %u.", _index);
-		goto err_exit;
-	}
-
-	dev_interface_details->cbSize = sizeof(SP_DEVICE_INTERFACE_DETAIL_DATA_A);
-	if (!pSetupDiGetDeviceInterfaceDetailA(*dev_info, &dev_interface_data,
-		dev_interface_details, size, &size, NULL)) {
-		usbi_err(ctx, "could not access interface data (actual) for index %u: %s",
-			_index, windows_error_str(0));
-	}
-
-	return dev_interface_details;
-
-err_exit:
-	pSetupDiDestroyDeviceInfoList(*dev_info);
-	*dev_info = INVALID_HANDLE_VALUE;
-	return NULL;
-}
-
-/* Hash table functions - modified From glibc 2.3.2:
-   [Aho,Sethi,Ullman] Compilers: Principles, Techniques and Tools, 1986
-   [Knuth]            The Art of Computer Programming, part 3 (6.4)  */
-typedef struct htab_entry {
-	unsigned long used;
-	char* str;
-} htab_entry;
-htab_entry* htab_table = NULL;
-usbi_mutex_t htab_write_mutex = NULL;
-unsigned long htab_size, htab_filled;
-
-/* For the used double hash method the table size has to be a prime. To
-   correct the user given table size we need a prime test.  This trivial
-   algorithm is adequate because the code is called only during init and
-   the number is likely to be small  */
-static int isprime(unsigned long number)
-{
-	// no even number will be passed
-	unsigned int divider = 3;
-
-	while((divider * divider < number) && (number % divider != 0))
-		divider += 2;
-
-	return (number % divider != 0);
-}
-
-/* Before using the hash table we must allocate memory for it.
-   We allocate one element more as the found prime number says.
-   This is done for more effective indexing as explained in the
-   comment for the hash function.  */
-static int htab_create(struct libusb_context *ctx, unsigned long nel)
-{
-	if (htab_table != NULL) {
-		usbi_err(ctx, "hash table already allocated");
-	}
-
-	// Create a mutex
-	usbi_mutex_init(&htab_write_mutex, NULL);
-
-	// Change nel to the first prime number not smaller as nel.
-	nel |= 1;
-	while(!isprime(nel))
-		nel += 2;
-
-	htab_size = nel;
-	usbi_dbg("using %d entries hash table", nel);
-	htab_filled = 0;
-
-	// allocate memory and zero out.
-	htab_table = (htab_entry*)calloc(htab_size + 1, sizeof(htab_entry));
-	if (htab_table == NULL) {
-		usbi_err(ctx, "could not allocate space for hash table");
-		return 0;
-	}
-
-	return 1;
-}
-
-/* After using the hash table it has to be destroyed.  */
-static void htab_destroy(void)
-{
-	size_t i;
-	if (htab_table == NULL) {
-		return;
-	}
-
-	for (i=0; i<htab_size; i++) {
-		if (htab_table[i].used) {
-			safe_free(htab_table[i].str);
-		}
-	}
-	usbi_mutex_destroy(&htab_write_mutex);
-	safe_free(htab_table);
-}
-
-/* This is the search function. It uses double hashing with open addressing.
-   We use an trick to speed up the lookup. The table is created with one
-   more element available. This enables us to use the index zero special.
-   This index will never be used because we store the first hash index in
-   the field used where zero means not used. Every other value means used.
-   The used field can be used as a first fast comparison for equality of
-   the stored and the parameter value. This helps to prevent unnecessary
-   expensive calls of strcmp.  */
-static unsigned long htab_hash(char* str)
-{
-	unsigned long hval, hval2;
-	unsigned long idx;
-	unsigned long r = 5381;
-	int c;
-	char* sz = str;
-
-	// Compute main hash value (algorithm suggested by Nokia)
-	while ((c = *sz++))
-		r = ((r << 5) + r) + c;
-	if (r == 0)
-		++r;
-
-	// compute table hash: simply take the modulus
-	hval = r % htab_size;
-	if (hval == 0)
-		++hval;
-
-	// Try the first index
-	idx = hval;
-
-	if (htab_table[idx].used) {
-		if ( (htab_table[idx].used == hval)
-		  && (safe_strcmp(str, htab_table[idx].str) == 0) ) {
-			// existing hash
-			return idx;
-		}
-		usbi_dbg("hash collision ('%s' vs '%s')", str, htab_table[idx].str);
-
-		// Second hash function, as suggested in [Knuth]
-		hval2 = 1 + hval % (htab_size - 2);
-
-		do {
-			// Because size is prime this guarantees to step through all available indexes
-			if (idx <= hval2) {
-				idx = htab_size + idx - hval2;
-			} else {
-				idx -= hval2;
-			}
-
-			// If we visited all entries leave the loop unsuccessfully
-			if (idx == hval) {
-				break;
-			}
-
-			// If entry is found use it.
-			if ( (htab_table[idx].used == hval)
-			  && (safe_strcmp(str, htab_table[idx].str) == 0) ) {
-				return idx;
-			}
-		}
-		while (htab_table[idx].used);
-	}
-
-	// Not found => New entry
-
-	// If the table is full return an error
-	if (htab_filled >= htab_size) {
-		usbi_err(NULL, "hash table is full (%d entries)", htab_size);
-		return 0;
-	}
-
-	// Concurrent threads might be storing the same entry at the same time
-	// (eg. "simultaneous" enums from different threads) => use a mutex
-	usbi_mutex_lock(&htab_write_mutex);
-	// Just free any previously allocated string (which should be the same as
-	// new one). The possibility of concurrent threads storing a collision
-	// string (same hash, different string) at the same time is extremely low
-	safe_free(htab_table[idx].str);
-	htab_table[idx].used = hval;
-	htab_table[idx].str = malloc(safe_strlen(str)+1);
-	if (htab_table[idx].str == NULL) {
-		usbi_err(NULL, "could not duplicate string for hash table");
-		usbi_mutex_unlock(&htab_write_mutex);
-		return 0;
-	}
-	memcpy(htab_table[idx].str, str, safe_strlen(str)+1);
-	++htab_filled;
-	usbi_mutex_unlock(&htab_write_mutex);
-
-	return idx;
-}
-
-/*
- * Returns the session ID of a device's nth level ancestor
- * If there's no device at the nth level, return 0
- */
-static unsigned long get_ancestor_session_id(DWORD devinst, unsigned level)
-{
-	DWORD parent_devinst;
-	unsigned long session_id = 0;
-	char* sanitized_path = NULL;
-	char path[MAX_PATH_LENGTH];
-	unsigned i;
-
-	if (level < 1) return 0;
-	for (i = 0; i<level; i++) {
-		if (CM_Get_Parent(&parent_devinst, devinst, 0) != CR_SUCCESS) {
-			return 0;
-		}
-		devinst = parent_devinst;
-	}
-	if (CM_Get_Device_IDA(devinst, path, MAX_PATH_LENGTH, 0) != CR_SUCCESS) {
-		return 0;
-	}
-	// TODO (post hotplug): try without sanitizing
-	sanitized_path = sanitize_path(path);
-	if (sanitized_path == NULL) {
-		return 0;
-	}
-	session_id = htab_hash(sanitized_path);
-	safe_free(sanitized_path);
-	return session_id;
-}
-
-/*
- * Populate the endpoints addresses of the device_priv interface helper structs
- */
-static int windows_assign_endpoints(struct libusb_device_handle *dev_handle, int iface, int altsetting)
-{
-	int i, r;
-	struct windows_device_priv *priv = _device_priv(dev_handle->dev);
-	struct libusb_config_descriptor *conf_desc;
-	const struct libusb_interface_descriptor *if_desc;
-	struct libusb_context *ctx = DEVICE_CTX(dev_handle->dev);
-
-	r = libusb_get_config_descriptor(dev_handle->dev, 0, &conf_desc);
-	if (r != LIBUSB_SUCCESS) {
-		usbi_warn(ctx, "could not read config descriptor: error %d", r);
-		return r;
-	}
-
-	if_desc = &conf_desc->interface[iface].altsetting[altsetting];
-	safe_free(priv->usb_interface[iface].endpoint);
-
-	if (if_desc->bNumEndpoints == 0) {
-		usbi_dbg("no endpoints found for interface %d", iface);
-		return LIBUSB_SUCCESS;
-	}
-
-	priv->usb_interface[iface].endpoint = malloc(if_desc->bNumEndpoints);
-	if (priv->usb_interface[iface].endpoint == NULL) {
-		return LIBUSB_ERROR_NO_MEM;
-	}
-
-	priv->usb_interface[iface].nb_endpoints = if_desc->bNumEndpoints;
-	for (i=0; i<if_desc->bNumEndpoints; i++) {
-		priv->usb_interface[iface].endpoint[i] = if_desc->endpoint[i].bEndpointAddress;
-		usbi_dbg("(re)assigned endpoint %02X to interface %d", priv->usb_interface[iface].endpoint[i], iface);
-	}
-	libusb_free_config_descriptor(conf_desc);
-
-	// Extra init is required for WinUSB endpoints
-	if (priv->apib->id == USB_API_WINUSB) {
-		return winusb_configure_endpoints(dev_handle, iface);
-	}
-
-	return LIBUSB_SUCCESS;
-}
-
-// Lookup for a match in the list of API driver names
-static bool is_api_driver(char* driver, uint8_t api)
-{
-	uint8_t i;
-	const char sep_str[2] = {LIST_SEPARATOR, 0};
-	char *tok, *tmp_str;
-	size_t len = safe_strlen(driver);
-
-	if (len == 0) return false;
-	tmp_str = calloc(len+1, 1);
-	if (tmp_str == NULL) return false;
-	memcpy(tmp_str, driver, len+1);
-	tok = strtok(tmp_str, sep_str);
-	while (tok != NULL) {
-		for (i=0; i<usb_api_backend[api].nb_driver_names; i++) {
-			if (safe_strcmp(tok, usb_api_backend[api].driver_name_list[i]) == 0) {
-				free(tmp_str);
-				return true;
-			}
-		}
-		tok = strtok(NULL, sep_str);
-	}
-	free (tmp_str);
-	return false;
-}
-
-/*
- * auto-claiming and auto-release helper functions
- */
-#if defined(AUTO_CLAIM)
-static int auto_claim(struct libusb_transfer *transfer, int *interface_number, int api_type)
-{
-	struct libusb_context *ctx = DEVICE_CTX(transfer->dev_handle->dev);
-	struct windows_device_handle_priv *handle_priv = _device_handle_priv(
-		transfer->dev_handle);
-	struct windows_device_priv *priv = _device_priv(transfer->dev_handle->dev);
-	int current_interface = *interface_number;
-	int r = LIBUSB_SUCCESS;
-
-	usbi_mutex_lock(&autoclaim_lock);
-	if (current_interface < 0)	// No serviceable interface was found
-	{
-		for (current_interface=0; current_interface<USB_MAXINTERFACES; current_interface++) {
-			// Must claim an interface of the same API type
-			if ( (priv->usb_interface[current_interface].apib->id == api_type)
-			  && (libusb_claim_interface(transfer->dev_handle, current_interface) == LIBUSB_SUCCESS) ) {
-				usbi_dbg("auto-claimed interface %d for control request", current_interface);
-				if (handle_priv->autoclaim_count[current_interface] != 0) {
-					usbi_warn(ctx, "program assertion failed - autoclaim_count was nonzero");
-				}
-				handle_priv->autoclaim_count[current_interface]++;
-				break;
-			}
-		}
-		if (current_interface == USB_MAXINTERFACES) {
-			usbi_err(ctx, "could not auto-claim any interface");
-			r = LIBUSB_ERROR_NOT_FOUND;
-		}
-	} else {
-		// If we have a valid interface that was autoclaimed, we must increment
-		// its autoclaim count so that we can prevent an early release.
-		if (handle_priv->autoclaim_count[current_interface] != 0) {
-			handle_priv->autoclaim_count[current_interface]++;
-		}
-	}
-	usbi_mutex_unlock(&autoclaim_lock);
-
-	*interface_number = current_interface;
-	return r;
-
-}
-
-static void auto_release(struct usbi_transfer *itransfer)
-{
-	struct windows_transfer_priv *transfer_priv = (struct windows_transfer_priv*)usbi_transfer_get_os_priv(itransfer);
-	struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	libusb_device_handle *dev_handle = transfer->dev_handle;
-	struct windows_device_handle_priv* handle_priv = _device_handle_priv(dev_handle);
-	int r;
-
-	usbi_mutex_lock(&autoclaim_lock);
-	if (handle_priv->autoclaim_count[transfer_priv->interface_number] > 0) {
-		handle_priv->autoclaim_count[transfer_priv->interface_number]--;
-		if (handle_priv->autoclaim_count[transfer_priv->interface_number] == 0) {
-			r = libusb_release_interface(dev_handle, transfer_priv->interface_number);
-			if (r == LIBUSB_SUCCESS) {
-				usbi_dbg("auto-released interface %d", transfer_priv->interface_number);
-			} else {
-				usbi_dbg("failed to auto-release interface %d (error=%d)",
-					transfer_priv->interface_number, r);
-			}
-		}
-	}
-	usbi_mutex_unlock(&autoclaim_lock);
-}
-#endif
-
-
-/*
- * init: libusb backend init function
- *
- * This function enumerates the HCDs (Host Controller Drivers) and populates our private HCD list
- * In our implementation, we equate Windows' "HCD" to LibUSB's "bus". Note that bus is zero indexed.
- * HCDs are not expected to change after init (might not hold true for hot pluggable USB PCI card?)
- */
-static int windows_init(struct libusb_context *ctx)
-{
-	int i, r = LIBUSB_ERROR_OTHER;
-	OSVERSIONINFO os_version;
-	HANDLE semaphore;
-	char sem_name[11+1+8]; // strlen(libusb_init)+'\0'+(32-bit hex PID)
-
-	sprintf(sem_name, "libusb_init%08X", (unsigned int)GetCurrentProcessId()&0xFFFFFFFF);
-	semaphore = CreateSemaphoreA(NULL, 1, 1, sem_name);
-	if (semaphore == NULL) {
-		usbi_err(ctx, "could not create semaphore: %s", windows_error_str(0));
-		return LIBUSB_ERROR_NO_MEM;
-	}
-
-	// A successful wait brings our semaphore count to 0 (unsignaled)
-	// => any concurent wait stalls until the semaphore's release
-	if (WaitForSingleObject(semaphore, INFINITE) != WAIT_OBJECT_0) {
-		usbi_err(ctx, "failure to access semaphore: %s", windows_error_str(0));
-		CloseHandle(semaphore);
-		return LIBUSB_ERROR_NO_MEM;
-	}
-
-	// NB: concurrent usage supposes that init calls are equally balanced with
-	// exit calls. If init is called more than exit, we will not exit properly
-	if ( ++concurrent_usage == 0 ) {	// First init?
-		// Detect OS version
-		memset(&os_version, 0, sizeof(OSVERSIONINFO));
-		os_version.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);
-		windows_version = WINDOWS_UNSUPPORTED;
-		if ((GetVersionEx(&os_version) != 0) && (os_version.dwPlatformId == VER_PLATFORM_WIN32_NT)) {
-			if ((os_version.dwMajorVersion == 5) && (os_version.dwMinorVersion == 1)) {
-				windows_version = WINDOWS_XP;
-			} else if ((os_version.dwMajorVersion == 5) && (os_version.dwMinorVersion == 2)) {
-				windows_version = WINDOWS_2003;	// also includes XP 64
-			} else if (os_version.dwMajorVersion >= 6) {
-				windows_version = WINDOWS_VISTA_AND_LATER;
-			}
-		}
-		if (windows_version == WINDOWS_UNSUPPORTED) {
-			usbi_err(ctx, "This version of Windows is NOT supported");
-			r = LIBUSB_ERROR_NOT_SUPPORTED;
-			goto init_exit;
-		}
-
-#if defined(AUTO_CLAIM)
-		// We need a lock for proper auto-release
-		usbi_mutex_init(&autoclaim_lock, NULL);
-#endif
-
-		// Initialize pollable file descriptors
-		init_polling();
-
-		// Load DLL imports
-		if (init_dlls() != LIBUSB_SUCCESS) {
-			usbi_err(ctx, "could not resolve DLL functions");
-			return LIBUSB_ERROR_NOT_FOUND;
-		}
-
-		// Initialize the low level APIs (we don't care about errors at this stage)
-		for (i=0; i<USB_API_MAX; i++) {
-			usb_api_backend[i].init(ctx);
-		}
-
-		// Because QueryPerformanceCounter might report different values when
-		// running on different cores, we create a separate thread for the timer
-		// calls, which we glue to the first core always to prevent timing discrepancies.
-		r = LIBUSB_ERROR_NO_MEM;
-		for (i = 0; i < 2; i++) {
-			timer_request[i] = CreateEvent(NULL, TRUE, FALSE, NULL);
-			if (timer_request[i] == NULL) {
-				usbi_err(ctx, "could not create timer request event %d - aborting", i);
-				goto init_exit;
-			}
-		}
-		timer_response = CreateSemaphore(NULL, 0, MAX_TIMER_SEMAPHORES, NULL);
-		if (timer_response == NULL) {
-			usbi_err(ctx, "could not create timer response semaphore - aborting");
-			goto init_exit;
-		}
-		timer_mutex = CreateMutex(NULL, FALSE, NULL);
-		if (timer_mutex == NULL) {
-			usbi_err(ctx, "could not create timer mutex - aborting");
-			goto init_exit;
-		}
-		timer_thread = (HANDLE)_beginthreadex(NULL, 0, windows_clock_gettime_threaded, NULL, 0, NULL);
-		if (timer_thread == NULL) {
-			usbi_err(ctx, "Unable to create timer thread - aborting");
-			goto init_exit;
-		}
-		SetThreadAffinityMask(timer_thread, 0);
-
-		// Create a hash table to store session ids. Second parameter is better if prime
-		htab_create(ctx, HTAB_SIZE);
-	}
-	// At this stage, either we went through full init successfully, or didn't need to
-	r = LIBUSB_SUCCESS;
-
-init_exit: // Holds semaphore here.
-	if (!concurrent_usage && r != LIBUSB_SUCCESS) { // First init failed?
-		if (timer_thread) {
-			SetEvent(timer_request[1]); // actually the signal to quit the thread.
-			if (WAIT_OBJECT_0 != WaitForSingleObject(timer_thread, INFINITE)) {
-				usbi_warn(ctx, "could not wait for timer thread to quit");
-				TerminateThread(timer_thread, 1); // shouldn't happen, but we're destroying
-												  // all objects it might have held anyway.
-			}
-			CloseHandle(timer_thread);
-			timer_thread = NULL;
-		}
-		for (i = 0; i < 2; i++) {
-			if (timer_request[i]) {
-				CloseHandle(timer_request[i]);
-				timer_request[i] = NULL;
-			}
-		}
-		if (timer_response) {
-			CloseHandle(timer_response);
-			timer_response = NULL;
-		}
-		if (timer_mutex) {
-			CloseHandle(timer_mutex);
-			timer_mutex = NULL;
-		}
-		htab_destroy();
-	}
-
-	if (r != LIBUSB_SUCCESS)
-		--concurrent_usage; // Not expected to call libusb_exit if we failed.
-
-	ReleaseSemaphore(semaphore, 1, NULL);	// increase count back to 1
-	CloseHandle(semaphore);
-	return r;
-}
-
-/*
- * HCD (root) hubs need to have their device descriptor manually populated
- *
- * Note that, like Microsoft does in the device manager, we populate the
- * Vendor and Device ID for HCD hubs with the ones from the PCI HCD device.
- */
-static int force_hcd_device_descriptor(struct libusb_device *dev)
-{
-	struct windows_device_priv *parent_priv, *priv = _device_priv(dev);
-	struct libusb_context *ctx = DEVICE_CTX(dev);
-	int vid, pid;
-
-	dev->num_configurations = 1;
-	priv->dev_descriptor.bLength = sizeof(USB_DEVICE_DESCRIPTOR);
-	priv->dev_descriptor.bDescriptorType = USB_DEVICE_DESCRIPTOR_TYPE;
-	priv->dev_descriptor.bNumConfigurations = 1;
-	priv->active_config = 1;
-
-	if (priv->parent_dev == NULL) {
-		usbi_err(ctx, "program assertion failed - HCD hub has no parent");
-		return LIBUSB_ERROR_NO_DEVICE;
-	}
-	parent_priv = _device_priv(priv->parent_dev);
-	if (sscanf(parent_priv->path, "\\\\.\\PCI#VEN_%04x&DEV_%04x%*s", &vid, &pid) == 2) {
-		priv->dev_descriptor.idVendor = (uint16_t)vid;
-		priv->dev_descriptor.idProduct = (uint16_t)pid;
-	} else {
-		usbi_warn(ctx, "could not infer VID/PID of HCD hub from '%s'", parent_priv->path);
-		priv->dev_descriptor.idVendor = 0x1d6b;		// Linux Foundation root hub
-		priv->dev_descriptor.idProduct = 1;
-	}
-	return LIBUSB_SUCCESS;
-}
-
-/*
- * fetch and cache all the config descriptors through I/O
- */
-static int cache_config_descriptors(struct libusb_device *dev, HANDLE hub_handle, char* device_id)
-{
-	DWORD size, ret_size;
-	struct libusb_context *ctx = DEVICE_CTX(dev);
-	struct windows_device_priv *priv = _device_priv(dev);
-	int r;
-	uint8_t i;
-
-	USB_CONFIGURATION_DESCRIPTOR_SHORT cd_buf_short;    // dummy request
-	PUSB_DESCRIPTOR_REQUEST cd_buf_actual = NULL;       // actual request
-	PUSB_CONFIGURATION_DESCRIPTOR cd_data = NULL;
-
-	if (dev->num_configurations == 0)
-		return LIBUSB_ERROR_INVALID_PARAM;
-
-	priv->config_descriptor = malloc(dev->num_configurations * sizeof(PUSB_CONFIGURATION_DESCRIPTOR));
-	if (priv->config_descriptor == NULL)
-		return LIBUSB_ERROR_NO_MEM;
-	for (i=0; i<dev->num_configurations; i++)
-		priv->config_descriptor[i] = NULL;
-
-	for (i=0, r=LIBUSB_SUCCESS; ; i++)
-	{
-		// safe loop: release all dynamic resources
-		safe_free(cd_buf_actual);
-
-		// safe loop: end of loop condition
-		if ((i >= dev->num_configurations) || (r != LIBUSB_SUCCESS))
-			break;
-
-		size = sizeof(USB_CONFIGURATION_DESCRIPTOR_SHORT);
-		memset(&cd_buf_short, 0, size);
-
-		cd_buf_short.req.ConnectionIndex = (ULONG)priv->port;
-		cd_buf_short.req.SetupPacket.bmRequest = LIBUSB_ENDPOINT_IN;
-		cd_buf_short.req.SetupPacket.bRequest = USB_REQUEST_GET_DESCRIPTOR;
-		cd_buf_short.req.SetupPacket.wValue = (USB_CONFIGURATION_DESCRIPTOR_TYPE << 8) | i;
-		cd_buf_short.req.SetupPacket.wIndex = i;
-		cd_buf_short.req.SetupPacket.wLength = (USHORT)(size - sizeof(USB_DESCRIPTOR_REQUEST));
-
-		// Dummy call to get the required data size
-		if (!DeviceIoControl(hub_handle, IOCTL_USB_GET_DESCRIPTOR_FROM_NODE_CONNECTION, &cd_buf_short, size,
-			&cd_buf_short, size, &ret_size, NULL)) {
-			usbi_err(ctx, "could not access configuration descriptor (dummy) for '%s': %s", device_id, windows_error_str(0));
-			LOOP_BREAK(LIBUSB_ERROR_IO);
-		}
-
-		if ((ret_size != size) || (cd_buf_short.data.wTotalLength < sizeof(USB_CONFIGURATION_DESCRIPTOR))) {
-			usbi_err(ctx, "unexpected configuration descriptor size (dummy) for '%s'.", device_id);
-			LOOP_BREAK(LIBUSB_ERROR_IO);
-		}
-
-		size = sizeof(USB_DESCRIPTOR_REQUEST) + cd_buf_short.data.wTotalLength;
-		if ((cd_buf_actual = (PUSB_DESCRIPTOR_REQUEST)malloc(size)) == NULL) {
-			usbi_err(ctx, "could not allocate configuration descriptor buffer for '%s'.", device_id);
-			LOOP_BREAK(LIBUSB_ERROR_NO_MEM);
-		}
-		memset(cd_buf_actual, 0, size);
-
-		// Actual call
-		cd_buf_actual->ConnectionIndex = (ULONG)priv->port;
-		cd_buf_actual->SetupPacket.bmRequest = LIBUSB_ENDPOINT_IN;
-		cd_buf_actual->SetupPacket.bRequest = USB_REQUEST_GET_DESCRIPTOR;
-		cd_buf_actual->SetupPacket.wValue = (USB_CONFIGURATION_DESCRIPTOR_TYPE << 8) | i;
-		cd_buf_actual->SetupPacket.wIndex = i;
-		cd_buf_actual->SetupPacket.wLength = (USHORT)(size - sizeof(USB_DESCRIPTOR_REQUEST));
-
-		if (!DeviceIoControl(hub_handle, IOCTL_USB_GET_DESCRIPTOR_FROM_NODE_CONNECTION, cd_buf_actual, size,
-			cd_buf_actual, size, &ret_size, NULL)) {
-			usbi_err(ctx, "could not access configuration descriptor (actual) for '%s': %s", device_id, windows_error_str(0));
-			LOOP_BREAK(LIBUSB_ERROR_IO);
-		}
-
-		cd_data = (PUSB_CONFIGURATION_DESCRIPTOR)((UCHAR*)cd_buf_actual+sizeof(USB_DESCRIPTOR_REQUEST));
-
-		if ((size != ret_size) || (cd_data->wTotalLength != cd_buf_short.data.wTotalLength)) {
-			usbi_err(ctx, "unexpected configuration descriptor size (actual) for '%s'.", device_id);
-			LOOP_BREAK(LIBUSB_ERROR_IO);
-		}
-
-		if (cd_data->bDescriptorType != USB_CONFIGURATION_DESCRIPTOR_TYPE) {
-			usbi_err(ctx, "not a configuration descriptor for '%s'", device_id);
-			LOOP_BREAK(LIBUSB_ERROR_IO);
-		}
-
-		usbi_dbg("cached config descriptor %d (bConfigurationValue=%d, %d bytes)",
-			i, cd_data->bConfigurationValue, cd_data->wTotalLength);
-
-		// Cache the descriptor
-		priv->config_descriptor[i] = malloc(cd_data->wTotalLength);
-		if (priv->config_descriptor[i] == NULL)
-			return LIBUSB_ERROR_NO_MEM;
-
-		memcpy(priv->config_descriptor[i], cd_data, cd_data->wTotalLength);
-	}
-	return LIBUSB_SUCCESS;
-}
-
-/*
- * Populate a libusb device structure
- */
-static int init_device(struct libusb_device* dev, struct libusb_device* parent_dev,
-					   uint8_t port_number, char* device_id, DWORD devinst)
-{
-	HANDLE handle;
-	DWORD size;
-	USB_NODE_CONNECTION_INFORMATION_EX conn_info;
-	struct windows_device_priv *priv, *parent_priv;
-	struct libusb_context *ctx = DEVICE_CTX(dev);
-	struct libusb_device* tmp_dev;
-	unsigned i;
-
-	if ((dev == NULL) || (parent_dev == NULL)) {
-		return LIBUSB_ERROR_NOT_FOUND;
-	}
-	priv = _device_priv(dev);
-	parent_priv = _device_priv(parent_dev);
-	if (parent_priv->apib->id != USB_API_HUB) {
-		usbi_warn(ctx, "parent for device '%s' is not a hub", device_id);
-		return LIBUSB_ERROR_NOT_FOUND;
-	}
-
-	// It is possible for the parent hub not to have been initialized yet
-	// If that's the case, lookup the ancestors to set the bus number
-	if (parent_dev->bus_number == 0) {
-		for (i=2; ; i++) {
-			tmp_dev = usbi_get_device_by_session_id(ctx, get_ancestor_session_id(devinst, i));
-			if (tmp_dev == NULL) break;
-			if (tmp_dev->bus_number != 0) {
-				usbi_dbg("got bus number from ancestor #%d", i);
-				parent_dev->bus_number = tmp_dev->bus_number;
-				break;
-			}
-		}
-	}
-	if (parent_dev->bus_number == 0) {
-		usbi_err(ctx, "program assertion failed: unable to find ancestor bus number for '%s'", device_id);
-		return LIBUSB_ERROR_NOT_FOUND;
-	}
-	dev->bus_number = parent_dev->bus_number;
-	priv->port = port_number;
-	priv->depth = parent_priv->depth + 1;
-	priv->parent_dev = parent_dev;
-
-	// If the device address is already set, we can stop here
-	if (dev->device_address != 0) {
-		return LIBUSB_SUCCESS;
-	}
-	memset(&conn_info, 0, sizeof(conn_info));
-	if (priv->depth != 0) {	// Not a HCD hub
-		handle = CreateFileA(parent_priv->path, GENERIC_WRITE, FILE_SHARE_WRITE, NULL, OPEN_EXISTING,
-			FILE_FLAG_OVERLAPPED, NULL);
-		if (handle == INVALID_HANDLE_VALUE) {
-			usbi_warn(ctx, "could not open hub %s: %s", parent_priv->path, windows_error_str(0));
-			return LIBUSB_ERROR_ACCESS;
-		}
-		size = sizeof(conn_info);
-		conn_info.ConnectionIndex = (ULONG)port_number;
-		if (!DeviceIoControl(handle, IOCTL_USB_GET_NODE_CONNECTION_INFORMATION_EX, &conn_info, size,
-			&conn_info, size, &size, NULL)) {
-			usbi_warn(ctx, "could not get node connection information for device '%s': %s",
-				device_id, windows_error_str(0));
-			safe_closehandle(handle);
-			return LIBUSB_ERROR_NO_DEVICE;
-		}
-		if (conn_info.ConnectionStatus == NoDeviceConnected) {
-			usbi_err(ctx, "device '%s' is no longer connected!", device_id);
-			safe_closehandle(handle);
-			return LIBUSB_ERROR_NO_DEVICE;
-		}
-		memcpy(&priv->dev_descriptor, &(conn_info.DeviceDescriptor), sizeof(USB_DEVICE_DESCRIPTOR));
-		dev->num_configurations = priv->dev_descriptor.bNumConfigurations;
-		priv->active_config = conn_info.CurrentConfigurationValue;
-		usbi_dbg("found %d configurations (active conf: %d)", dev->num_configurations, priv->active_config);
-		// If we can't read the config descriptors, just set the number of confs to zero
-		if (cache_config_descriptors(dev, handle, device_id) != LIBUSB_SUCCESS) {
-			dev->num_configurations = 0;
-			priv->dev_descriptor.bNumConfigurations = 0;
-		}
-		safe_closehandle(handle);
-
-		if (conn_info.DeviceAddress > UINT8_MAX) {
-			usbi_err(ctx, "program assertion failed: device address overflow");
-		}
-		dev->device_address = (uint8_t)conn_info.DeviceAddress;
-		switch (conn_info.Speed) {
-		case 0: dev->speed = LIBUSB_SPEED_LOW; break;
-		case 1: dev->speed = LIBUSB_SPEED_FULL; break;
-		case 2: dev->speed = LIBUSB_SPEED_HIGH; break;
-		default:
-			usbi_warn(ctx, "Got unknown device speed %d", conn_info.Speed);
-			break;
-		}
-	} else {
-		dev->device_address = UINT8_MAX;	// Hubs from HCD have a devaddr of 255
-		force_hcd_device_descriptor(dev);
-	}
-
-	usbi_dbg("(bus: %d, addr: %d, depth: %d, port: %d): '%s'",
-		dev->bus_number, dev->device_address, priv->depth, priv->port, device_id);
-
-	return LIBUSB_SUCCESS;
-}
-
-// Returns the api type, or 0 if not found/unsupported
-static uint8_t get_api_type(struct libusb_context *ctx,
-						HDEVINFO *dev_info, SP_DEVINFO_DATA *dev_info_data)
-{
-	// Precedence for filter drivers vs driver is in the order of this array
-	struct driver_lookup lookup[3] = {
-		{"\0\0", SPDRP_SERVICE, "driver"},
-		{"\0\0", SPDRP_UPPERFILTERS, "upper filter driver"},
-		{"\0\0", SPDRP_LOWERFILTERS, "lower filter driver"}
-	};
-	DWORD size, reg_type;
-	unsigned k, l;
-	uint8_t api;
-
-	// Check the service & filter names to know the API we should use
-	for (k=0; k<3; k++) {
-		if (pSetupDiGetDeviceRegistryPropertyA(*dev_info, dev_info_data, lookup[k].reg_prop,
-			&reg_type, (BYTE*)lookup[k].list, MAX_KEY_LENGTH, &size)) {
-			// Turn the REG_SZ SPDRP_SERVICE into REG_MULTI_SZ
-			if (lookup[k].reg_prop == SPDRP_SERVICE) {
-				// our buffers are MAX_KEY_LENGTH+1 so we can overflow if needed
-				lookup[k].list[safe_strlen(lookup[k].list)+1] = 0;
-			}
-			// MULTI_SZ is a pain to work with. Turn it into something much more manageable
-			// NB: none of the driver names we check against contain LIST_SEPARATOR,
-			// (currently ';'), so even if an unsuported one does, it's not an issue
-			for (l=0; (lookup[k].list[l] != 0) || (lookup[k].list[l+1] != 0); l++) {
-				if (lookup[k].list[l] == 0) {
-					lookup[k].list[l] = LIST_SEPARATOR;
-				}
-			}
-			upperize(lookup[k].list);
-			usbi_dbg("%s(s): %s", lookup[k].designation, lookup[k].list);
-		} else {
-			if (GetLastError() != ERROR_INVALID_DATA) {
-				usbi_dbg("could not access %s: %s", lookup[k].designation, windows_error_str(0));
-			}
-			lookup[k].list[0] = 0;
-		}
-	}
-
-	for (api=1; api<USB_API_MAX; api++) {
-		for (k=0; k<3; k++) {
-			if (is_api_driver(lookup[k].list, api)) {
-				usbi_dbg("matched %s name against %s", lookup[k].designation, usb_api_backend[api].designation);
-				break;
-			}
-		}
-		if (k >= 3) continue;
-		return api;
-	}
-	return 0;
-}
-
-static int set_composite_interface(struct libusb_context* ctx, struct libusb_device* dev,
-							char* dev_interface_path, char* device_id, uint8_t api)
-{
-	unsigned i;
-	struct windows_device_priv *priv = _device_priv(dev);
-	int interface_number;
-
-	if (priv->apib->id != USB_API_COMPOSITE) {
-		usbi_err(ctx, "program assertion failed: '%s' is not composite", device_id);
-		return LIBUSB_ERROR_NO_DEVICE;
-	}
-
-	// Because MI_## are not necessarily in sequential order (some composite
-	// devices will have only MI_00 & MI_03 for instance), we retrieve the actual
-	// interface number from the path's MI value
-	interface_number = 0;
-	for (i=0; device_id[i] != 0; ) {
-		if ( (device_id[i++] == 'M') && (device_id[i++] == 'I')
-		  && (device_id[i++] == '_') ) {
-			interface_number = (device_id[i++] - '0')*10;
-			interface_number += device_id[i] - '0';
-			break;
-		}
-	}
-
-	if (device_id[i] == 0) {
-		usbi_warn(ctx, "failure to read interface number for %s. Using default value %d",
-			device_id, interface_number);
-	}
-
-	if (priv->usb_interface[interface_number].path != NULL) {
-		usbi_warn(ctx, "interface[%d] already set - ignoring: %s", interface_number, device_id);
-		return LIBUSB_ERROR_ACCESS;
-	}
-
-	usbi_dbg("interface[%d] = %s", interface_number, dev_interface_path);
-	priv->usb_interface[interface_number].path = dev_interface_path;
-	priv->usb_interface[interface_number].apib = &usb_api_backend[api];
-	priv->composite_api_flags |= 1<<api;
-
-	return LIBUSB_SUCCESS;
-}
-
-/*
- * get_device_list: libusb backend device enumeration function
- */
-static int windows_get_device_list(struct libusb_context *ctx, struct discovered_devs **_discdevs)
-{
-	struct discovered_devs *discdevs = *_discdevs;
-	HDEVINFO dev_info = { 0 };
-	char* usb_class[2] = {"USB", "NUSB3"};
-	SP_DEVINFO_DATA dev_info_data;
-	SP_DEVICE_INTERFACE_DETAIL_DATA_A *dev_interface_details = NULL;
-#define MAX_ENUM_GUIDS 64
-	const GUID* guid[MAX_ENUM_GUIDS];
-#define HCD_PASS 0
-#define HUB_PASS 1
-#define GEN_PASS 2
-#define DEV_PASS 3
-	int r = LIBUSB_SUCCESS;
-	int class_index = 0;
-	unsigned int nb_guids, pass, i, j, ancestor;
-	char path[MAX_PATH_LENGTH];
-	char strbuf[MAX_PATH_LENGTH];
-	struct libusb_device *dev, *parent_dev;
-	struct windows_device_priv *priv, *parent_priv;
-	char* dev_interface_path = NULL;
-	char* dev_id_path = NULL;
-	unsigned long session_id;
-	DWORD size, reg_type, port_nr, install_state;
-	BOOL b = FALSE;
-	HKEY key;
-	WCHAR guid_string_w[MAX_GUID_STRING_LENGTH];
-	GUID* if_guid;
-	LONG s;
-	uint8_t api;
-	// Keep a list of newly allocated devs to unref
-	libusb_device** unref_list;
-	unsigned int unref_size = 64;
-	unsigned int unref_cur = 0;
-
-	// PASS 1 : (re)enumerate HCDs (allows for HCD hotplug)
-	// PASS 2 : (re)enumerate HUBS
-	// PASS 3 : (re)enumerate generic USB devices (including driverless)
-	//           and list additional USB device interface GUIDs to explore
-	// PASS 4 : (re)enumerate master USB devices that have a device interface
-	// PASS 5+: (re)enumerate device interfaced GUIDs and set the device interfaces.
-
-	// Init the GUID table
-	guid[HCD_PASS] = &GUID_DEVINTERFACE_USB_HOST_CONTROLLER;
-	guid[HUB_PASS] = &GUID_DEVINTERFACE_USB_HUB;
-	guid[GEN_PASS] = NULL;
-	guid[DEV_PASS] = &GUID_DEVINTERFACE_USB_DEVICE;
-	nb_guids = DEV_PASS+1;
-
-	unref_list = malloc(unref_size*sizeof(libusb_device*));
-	if (unref_list == NULL) {
-		return LIBUSB_ERROR_NO_MEM;
-	}
-
-	for (pass = 0; ((pass < nb_guids) && (r == LIBUSB_SUCCESS)); pass++) {
-//#define ENUM_DEBUG
-#ifdef ENUM_DEBUG
-		switch(pass) {
-		case HCD_PASS:
-			usbi_dbg("PROCESSING HCDs %s", guid_to_string(guid[pass]));
-			break;
-		case HUB_PASS:
-			usbi_dbg("PROCESSING HUBs %s", guid_to_string(guid[pass]));
-			break;
-		case DEV_PASS:
-			usbi_dbg("PROCESSING DEVs %s", guid_to_string(guid[pass]));
-			break;
-		case GEN_PASS:
-			usbi_dbg("PROCESSING GENs");
-			break;
-		default:
-			usbi_dbg("PROCESSING EXTs %s", guid_to_string(guid[pass]));
-			break;
-		}
-#endif
-		for (i = 0; ; i++) {
-			// safe loop: free up any (unprotected) dynamic resource
-			// NB: this is always executed before breaking the loop
-			safe_free(dev_interface_details);
-			safe_free(dev_interface_path);
-			safe_free(dev_id_path);
-			session_id = 0;
-			priv = parent_priv = NULL;
-			dev = parent_dev = NULL;
-
-			// Safe loop: end of loop conditions
-			if (r != LIBUSB_SUCCESS) {
-				break;
-			}
-			if ((pass == HCD_PASS) && (i == UINT8_MAX)) {
-				usbi_warn(ctx, "program assertion failed - found more than %d buses, skipping the rest.", UINT8_MAX);
-				break;
-			}
-			if (pass != GEN_PASS) {
-				// Except for GEN, all passes deal with device interfaces
-				dev_interface_details = get_interface_details(ctx, &dev_info, &dev_info_data, guid[pass], i);
-				if (dev_interface_details == NULL) {
-					break;
-				} else {
-					dev_interface_path = sanitize_path(dev_interface_details->DevicePath);
-					if (dev_interface_path == NULL) {
-						usbi_warn(ctx, "could not sanitize device interface path for '%s'", dev_interface_details->DevicePath);
-						continue;
-					}
-				}
-			} else {
-				// Workaround for a Nec/Renesas USB 3.0 driver bug where root hubs are
-				// being listed under the "NUSB3" PnP Symbolic Name rather than "USB"
-				while ( (class_index < 2) &&
-					    (!(b = get_devinfo_data(ctx, &dev_info, &dev_info_data, usb_class[class_index], i))) ) {
-						class_index++;
-						i = 0;
-				}
-				if (!b) break;
-			}
-
-			// Read the Device ID path. This is what we'll use as UID
-			// Note that if the device is plugged in a different port or hub, the Device ID changes
-			if (CM_Get_Device_IDA(dev_info_data.DevInst, path, sizeof(path), 0) != CR_SUCCESS) {
-				usbi_warn(ctx, "could not read the device id path for devinst %X, skipping",
-					dev_info_data.DevInst);
-				continue;
-			}
-			dev_id_path = sanitize_path(path);
-			if (dev_id_path == NULL) {
-				usbi_warn(ctx, "could not sanitize device id path for devinst %X, skipping",
-					dev_info_data.DevInst);
-				continue;
-			}
-#ifdef ENUM_DEBUG
-			usbi_dbg("PRO: %s", dev_id_path);
-#endif
-
-			// The SPDRP_ADDRESS for USB devices is the device port number on the hub
-			port_nr = 0;
-			if ((pass >= HUB_PASS) && (pass <= GEN_PASS)) {
-				if ( (!pSetupDiGetDeviceRegistryPropertyA(dev_info, &dev_info_data, SPDRP_ADDRESS,
-					&reg_type, (BYTE*)&port_nr, 4, &size))
-				  || (size != 4) ) {
-					usbi_warn(ctx, "could not retrieve port number for device '%s', skipping: %s",
-						dev_id_path, windows_error_str(0));
-					continue;
-				}
-			}
-
-			// Set API to use or get additional data from generic pass
-			api = USB_API_UNSUPPORTED;
-			switch (pass) {
-			case HCD_PASS:
-				break;
-			case GEN_PASS:
-				// We use the GEN pass to detect driverless devices...
-				size = sizeof(strbuf);
-				if (!pSetupDiGetDeviceRegistryPropertyA(dev_info, &dev_info_data, SPDRP_DRIVER,
-					&reg_type, (BYTE*)strbuf, size, &size)) {
-						usbi_info(ctx, "The following device has no driver: '%s'", dev_id_path);
-						usbi_info(ctx, "libusb will not be able to access it.");
-				}
-				// ...and to add the additional device interface GUIDs
-				key = pSetupDiOpenDevRegKey(dev_info, &dev_info_data, DICS_FLAG_GLOBAL, 0, DIREG_DEV, KEY_READ);
-				if (key != INVALID_HANDLE_VALUE) {
-					size = sizeof(guid_string_w);
-					s = pRegQueryValueExW(key, L"DeviceInterfaceGUIDs", NULL, &reg_type,
-						(BYTE*)guid_string_w, &size);
-					pRegCloseKey(key);
-					if (s == ERROR_SUCCESS) {
-						if (nb_guids >= MAX_ENUM_GUIDS) {
-							// If this assert is ever reported, grow a GUID table dynamically
-							usbi_err(ctx, "program assertion failed: too many GUIDs");
-							LOOP_BREAK(LIBUSB_ERROR_OVERFLOW);
-						}
-						if_guid = calloc(1, sizeof(GUID));
-						pCLSIDFromString(guid_string_w, if_guid);
-						guid[nb_guids++] = if_guid;
-						usbi_dbg("extra GUID: %s", guid_to_string(if_guid));
-					}
-				}
-				break;
-			default:
-				// Get the API type (after checking that the driver installation is OK)
-				if ( (!pSetupDiGetDeviceRegistryPropertyA(dev_info, &dev_info_data, SPDRP_INSTALL_STATE,
-					&reg_type, (BYTE*)&install_state, 4, &size))
-				  || (size != 4) ){
-					usbi_warn(ctx, "could not detect installation state of driver for '%s': %s",
-						dev_id_path, windows_error_str(0));
-				} else if (install_state != 0) {
-					usbi_warn(ctx, "driver for device '%s' is reporting an issue (code: %d) - skipping",
-						dev_id_path, install_state);
-					continue;
-				}
-				api = get_api_type(ctx, &dev_info, &dev_info_data);
-				break;
-			}
-
-			// Find parent device (for the passes that need it)
-			switch (pass) {
-			case HCD_PASS:
-			case DEV_PASS:
-			case HUB_PASS:
-				break;
-			default:
-				// Go through the ancestors until we see a face we recognize
-				parent_dev = NULL;
-				for (ancestor = 1; parent_dev == NULL; ancestor++) {
-					session_id = get_ancestor_session_id(dev_info_data.DevInst, ancestor);
-					if (session_id == 0) {
-						break;
-					}
-					parent_dev = usbi_get_device_by_session_id(ctx, session_id);
-				}
-				if (parent_dev == NULL) {
-					usbi_dbg("unlisted ancestor for '%s' (newly connected, etc.) - ignoring", dev_id_path);
-					continue;
-				}
-				parent_priv = _device_priv(parent_dev);
-				// virtual USB devices are also listed during GEN - don't process these yet
-				if ( (pass == GEN_PASS) && (parent_priv->apib->id != USB_API_HUB) ) {
-					continue;
-				}
-				break;
-			}
-
-			// Create new or match existing device, using the (hashed) device_id as session id
-			if (pass <= DEV_PASS) {	// For subsequent passes, we'll lookup the parent
-				// These are the passes that create "new" devices
-				session_id = htab_hash(dev_id_path);
-				dev = usbi_get_device_by_session_id(ctx, session_id);
-				if (dev == NULL) {
-					if (pass == DEV_PASS) {
-						// This can occur if the OS only reports a newly plugged device after we started enum
-						usbi_warn(ctx, "'%s' was only detected in late pass (newly connected device?)"
-							" - ignoring", dev_id_path);
-						continue;
-					}
-					usbi_dbg("allocating new device for session [%X]", session_id);
-					if ((dev = usbi_alloc_device(ctx, session_id)) == NULL) {
-						LOOP_BREAK(LIBUSB_ERROR_NO_MEM);
-					}
-					windows_device_priv_init(dev);
-					// Keep track of devices that need unref
-					unref_list[unref_cur++] = dev;
-					if (unref_cur > unref_size) {
-						unref_size += 64;
-						unref_list = realloc(unref_list, unref_size*sizeof(libusb_device*));
-						if (unref_list == NULL) {
-							usbi_err(ctx, "could not realloc list for unref - aborting.");
-							LOOP_BREAK(LIBUSB_ERROR_NO_MEM);
-						}
-					}
-				} else {
-					usbi_dbg("found existing device for session [%X] (%d.%d)",
-						session_id, dev->bus_number, dev->device_address);
-				}
-				priv = _device_priv(dev);
-			}
-
-			// Setup device
-			switch (pass) {
-			case HCD_PASS:
-				dev->bus_number = (uint8_t)(i + 1);	// bus 0 is reserved for disconnected
-				dev->device_address = 0;
-				dev->num_configurations = 0;
-				priv->apib = &usb_api_backend[USB_API_HUB];
-				priv->depth = UINT8_MAX;	// Overflow to 0 for HCD Hubs
-				priv->path = dev_interface_path; dev_interface_path = NULL;
-				break;
-			case HUB_PASS:
-			case DEV_PASS:
-				// If the device has already been setup, don't do it again
-				if (priv->path != NULL)
-					break;
-				// Take care of API initialization
-				priv->path = dev_interface_path; dev_interface_path = NULL;
-				priv->apib = &usb_api_backend[api];
-				switch(api) {
-				case USB_API_COMPOSITE:
-				case USB_API_HUB:
-					break;
-				default:
-					// For other devices, the first interface is the same as the device
-					priv->usb_interface[0].path = malloc(safe_strlen(priv->path)+1);
-					if (priv->usb_interface[0].path != NULL) {
-						safe_strcpy(priv->usb_interface[0].path, safe_strlen(priv->path)+1, priv->path);
-					}
-					// The following is needed if we want API calls to work for both simple
-					// and composite devices.
-					for(j=0; j<USB_MAXINTERFACES; j++) {
-						priv->usb_interface[j].apib = &usb_api_backend[api];
-					}
-					break;
-				}
-				break;
-			case GEN_PASS:
-				r = init_device(dev, parent_dev, (uint8_t)port_nr, dev_id_path, dev_info_data.DevInst);
-				if (r == LIBUSB_SUCCESS) {
-					// Append device to the list of discovered devices
-					discdevs = discovered_devs_append(*_discdevs, dev);
-					if (!discdevs) {
-						LOOP_BREAK(LIBUSB_ERROR_NO_MEM);
-					}
-					*_discdevs = discdevs;
-				} else if (r == LIBUSB_ERROR_NO_DEVICE) {
-					// This can occur if the device was disconnected but Windows hasn't
-					// refreshed its enumeration yet - in that case, we ignore the device
-					r = LIBUSB_SUCCESS;
-				}
-				break;
-			default:	// later passes
-				if (parent_priv->apib->id == USB_API_COMPOSITE) {
-					usbi_dbg("setting composite interface for [%lX]:", parent_dev->session_data);
-					switch (set_composite_interface(ctx, parent_dev, dev_interface_path, dev_id_path, api)) {
-					case LIBUSB_SUCCESS:
-						dev_interface_path = NULL;
-						break;
-					case LIBUSB_ERROR_ACCESS:
-						// interface has already been set => make sure dev_interface_path is freed then
-						break;
-					default:
-						LOOP_BREAK(r);
-						break;
-					}
-				}
-				break;
-			}
-		}
-	}
-
-	// Free any additional GUIDs
-	for (pass = DEV_PASS+1; pass < nb_guids; pass++) {
-		safe_free(guid[pass]);
-	}
-
-	// Unref newly allocated devs
-	for (i=0; i<unref_cur; i++) {
-		safe_unref_device(unref_list[i]);
-	}
-	safe_free(unref_list);
-
-	return r;
-}
-
-/*
- * exit: libusb backend deinitialization function
- */
-static void windows_exit(void)
-{
-	int i;
-	HANDLE semaphore;
-	char sem_name[11+1+8]; // strlen(libusb_init)+'\0'+(32-bit hex PID)
-
-	sprintf(sem_name, "libusb_init%08X", (unsigned int)GetCurrentProcessId()&0xFFFFFFFF);
-	semaphore = CreateSemaphoreA(NULL, 1, 1, sem_name);
-	if (semaphore == NULL) {
-		return;
-	}
-
-	// A successful wait brings our semaphore count to 0 (unsignaled)
-	// => any concurent wait stalls until the semaphore release
-	if (WaitForSingleObject(semaphore, INFINITE) != WAIT_OBJECT_0) {
-		CloseHandle(semaphore);
-		return;
-	}
-
-	// Only works if exits and inits are balanced exactly
-	if (--concurrent_usage < 0) {	// Last exit
-		for (i=0; i<USB_API_MAX; i++) {
-			usb_api_backend[i].exit();
-		}
-		exit_polling();
-
-		if (timer_thread) {
-			SetEvent(timer_request[1]); // actually the signal to quit the thread.
-			if (WAIT_OBJECT_0 != WaitForSingleObject(timer_thread, INFINITE)) {
-				usbi_dbg("could not wait for timer thread to quit");
-				TerminateThread(timer_thread, 1);
-			}
-			CloseHandle(timer_thread);
-			timer_thread = NULL;
-		}
-		for (i = 0; i < 2; i++) {
-			if (timer_request[i]) {
-				CloseHandle(timer_request[i]);
-				timer_request[i] = NULL;
-			}
-		}
-		if (timer_response) {
-			CloseHandle(timer_response);
-			timer_response = NULL;
-		}
-		if (timer_mutex) {
-			CloseHandle(timer_mutex);
-			timer_mutex = NULL;
-		}
-		htab_destroy();
-	}
-
-	ReleaseSemaphore(semaphore, 1, NULL);	// increase count back to 1
-	CloseHandle(semaphore);
-}
-
-static int windows_get_device_descriptor(struct libusb_device *dev, unsigned char *buffer, int *host_endian)
-{
-	struct windows_device_priv *priv = _device_priv(dev);
-
-	memcpy(buffer, &(priv->dev_descriptor), DEVICE_DESC_LENGTH);
-	*host_endian = 0;
-
-	return LIBUSB_SUCCESS;
-}
-
-static int windows_get_config_descriptor(struct libusb_device *dev, uint8_t config_index, unsigned char *buffer, size_t len, int *host_endian)
-{
-	struct windows_device_priv *priv = _device_priv(dev);
-	PUSB_CONFIGURATION_DESCRIPTOR config_header;
-	size_t size;
-
-	// config index is zero based
-	if (config_index >= dev->num_configurations)
-		return LIBUSB_ERROR_INVALID_PARAM;
-
-	if ((priv->config_descriptor == NULL) || (priv->config_descriptor[config_index] == NULL))
-		return LIBUSB_ERROR_NOT_FOUND;
-
-	config_header = (PUSB_CONFIGURATION_DESCRIPTOR)priv->config_descriptor[config_index];
-
-	size = min(config_header->wTotalLength, len);
-	memcpy(buffer, priv->config_descriptor[config_index], size);
-
-	return LIBUSB_SUCCESS;
-}
-
-/*
- * return the cached copy of the active config descriptor
- */
-static int windows_get_active_config_descriptor(struct libusb_device *dev, unsigned char *buffer, size_t len, int *host_endian)
-{
-	struct windows_device_priv *priv = _device_priv(dev);
-
-	if (priv->active_config == 0)
-		return LIBUSB_ERROR_NOT_FOUND;
-
-	// config index is zero based
-	return windows_get_config_descriptor(dev, (uint8_t)(priv->active_config-1), buffer, len, host_endian);
-}
-
-static int windows_open(struct libusb_device_handle *dev_handle)
-{
-	struct windows_device_priv *priv = _device_priv(dev_handle->dev);
-	struct libusb_context *ctx = DEVICE_CTX(dev_handle->dev);
-
-	if (priv->apib == NULL) {
-		usbi_err(ctx, "program assertion failed - device is not initialized");
-		return LIBUSB_ERROR_NO_DEVICE;
-	}
-
-	return priv->apib->open(dev_handle);
-}
-
-static void windows_close(struct libusb_device_handle *dev_handle)
-{
-	struct windows_device_priv *priv = _device_priv(dev_handle->dev);
-
-	priv->apib->close(dev_handle);
-}
-
-static int windows_get_configuration(struct libusb_device_handle *dev_handle, int *config)
-{
-	struct windows_device_priv *priv = _device_priv(dev_handle->dev);
-
-	if (priv->active_config == 0) {
-		*config = 0;
-		return LIBUSB_ERROR_NOT_FOUND;
-	}
-
-	*config = priv->active_config;
-	return LIBUSB_SUCCESS;
-}
-
-/*
- * from http://msdn.microsoft.com/en-us/library/ms793522.aspx: "The port driver
- * does not currently expose a service that allows higher-level drivers to set
- * the configuration."
- */
-static int windows_set_configuration(struct libusb_device_handle *dev_handle, int config)
-{
-	struct windows_device_priv *priv = _device_priv(dev_handle->dev);
-	int r = LIBUSB_SUCCESS;
-
-	if (config >= USB_MAXCONFIG)
-		return LIBUSB_ERROR_INVALID_PARAM;
-
-	r = libusb_control_transfer(dev_handle, LIBUSB_ENDPOINT_OUT |
-		LIBUSB_REQUEST_TYPE_STANDARD | LIBUSB_RECIPIENT_DEVICE,
-		LIBUSB_REQUEST_SET_CONFIGURATION, (uint16_t)config,
-		0, NULL, 0, 1000);
-
-	if (r == LIBUSB_SUCCESS) {
-		priv->active_config = (uint8_t)config;
-	}
-	return r;
-}
-
-static int windows_claim_interface(struct libusb_device_handle *dev_handle, int iface)
-{
-	int r = LIBUSB_SUCCESS;
-	struct windows_device_priv *priv = _device_priv(dev_handle->dev);
-
-	if (iface >= USB_MAXINTERFACES)
-		return LIBUSB_ERROR_INVALID_PARAM;
-
-	safe_free(priv->usb_interface[iface].endpoint);
-	priv->usb_interface[iface].nb_endpoints= 0;
-
-	r = priv->apib->claim_interface(dev_handle, iface);
-
-	if (r == LIBUSB_SUCCESS) {
-		r = windows_assign_endpoints(dev_handle, iface, 0);
-	}
-
-	return r;
-}
-
-static int windows_set_interface_altsetting(struct libusb_device_handle *dev_handle, int iface, int altsetting)
-{
-	int r = LIBUSB_SUCCESS;
-	struct windows_device_priv *priv = _device_priv(dev_handle->dev);
-
-	safe_free(priv->usb_interface[iface].endpoint);
-	priv->usb_interface[iface].nb_endpoints= 0;
-
-	r = priv->apib->set_interface_altsetting(dev_handle, iface, altsetting);
-
-	if (r == LIBUSB_SUCCESS) {
-		r = windows_assign_endpoints(dev_handle, iface, altsetting);
-	}
-
-	return r;
-}
-
-static int windows_release_interface(struct libusb_device_handle *dev_handle, int iface)
-{
-	struct windows_device_priv *priv = _device_priv(dev_handle->dev);
-
-	return priv->apib->release_interface(dev_handle, iface);
-}
-
-static int windows_clear_halt(struct libusb_device_handle *dev_handle, unsigned char endpoint)
-{
-	struct windows_device_priv *priv = _device_priv(dev_handle->dev);
-	return priv->apib->clear_halt(dev_handle, endpoint);
-}
-
-static int windows_reset_device(struct libusb_device_handle *dev_handle)
-{
-	struct windows_device_priv *priv = _device_priv(dev_handle->dev);
-	return priv->apib->reset_device(dev_handle);
-}
-
-// The 3 functions below are unlikely to ever get supported on Windows
-static int windows_kernel_driver_active(struct libusb_device_handle *dev_handle, int iface)
-{
-	return LIBUSB_ERROR_NOT_SUPPORTED;
-}
-
-static int windows_attach_kernel_driver(struct libusb_device_handle *dev_handle, int iface)
-{
-	return LIBUSB_ERROR_NOT_SUPPORTED;
-}
-
-static int windows_detach_kernel_driver(struct libusb_device_handle *dev_handle, int iface)
-{
-	return LIBUSB_ERROR_NOT_SUPPORTED;
-}
-
-static void windows_destroy_device(struct libusb_device *dev)
-{
-	windows_device_priv_release(dev);
-}
-
-static void windows_clear_transfer_priv(struct usbi_transfer *itransfer)
-{
-	struct windows_transfer_priv *transfer_priv = (struct windows_transfer_priv*)usbi_transfer_get_os_priv(itransfer);
-
-	usbi_free_fd(transfer_priv->pollable_fd.fd);
-#if defined(AUTO_CLAIM)
-	// When auto claim is in use, attempt to release the auto-claimed interface
-	auto_release(itransfer);
-#endif
-}
-
-static int submit_bulk_transfer(struct usbi_transfer *itransfer)
-{
-	struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	struct libusb_context *ctx = DEVICE_CTX(transfer->dev_handle->dev);
-	struct windows_transfer_priv *transfer_priv = (struct windows_transfer_priv*)usbi_transfer_get_os_priv(itransfer);
-	struct windows_device_priv *priv = _device_priv(transfer->dev_handle->dev);
-	int r;
-
-	r = priv->apib->submit_bulk_transfer(itransfer);
-	if (r != LIBUSB_SUCCESS) {
-		return r;
-	}
-
-	usbi_add_pollfd(ctx, transfer_priv->pollable_fd.fd,
-		(short)((transfer->endpoint & LIBUSB_ENDPOINT_IN)?POLLIN:POLLOUT));
-#if !defined(DYNAMIC_FDS)
-	usbi_fd_notification(ctx);
-#endif
-
-	return LIBUSB_SUCCESS;
-}
-
-static int submit_iso_transfer(struct usbi_transfer *itransfer)
-{
-	struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	struct libusb_context *ctx = DEVICE_CTX(transfer->dev_handle->dev);
-	struct windows_transfer_priv *transfer_priv = (struct windows_transfer_priv*)usbi_transfer_get_os_priv(itransfer);
-	struct windows_device_priv *priv = _device_priv(transfer->dev_handle->dev);
-	int r;
-
-	r = priv->apib->submit_iso_transfer(itransfer);
-	if (r != LIBUSB_SUCCESS) {
-		return r;
-	}
-
-	usbi_add_pollfd(ctx, transfer_priv->pollable_fd.fd,
-		(short)((transfer->endpoint & LIBUSB_ENDPOINT_IN)?POLLIN:POLLOUT));
-#if !defined(DYNAMIC_FDS)
-	usbi_fd_notification(ctx);
-#endif
-
-	return LIBUSB_SUCCESS;
-}
-
-static int submit_control_transfer(struct usbi_transfer *itransfer)
-{
-	struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	struct libusb_context *ctx = DEVICE_CTX(transfer->dev_handle->dev);
-	struct windows_transfer_priv *transfer_priv = (struct windows_transfer_priv*)usbi_transfer_get_os_priv(itransfer);
-	struct windows_device_priv *priv = _device_priv(transfer->dev_handle->dev);
-	int r;
-
-	r = priv->apib->submit_control_transfer(itransfer);
-	if (r != LIBUSB_SUCCESS) {
-		return r;
-	}
-
-	usbi_add_pollfd(ctx, transfer_priv->pollable_fd.fd, POLLIN);
-#if !defined(DYNAMIC_FDS)
-	usbi_fd_notification(ctx);
-#endif
-
-	return LIBUSB_SUCCESS;
-
-}
-
-static int windows_submit_transfer(struct usbi_transfer *itransfer)
-{
-	struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-
-	switch (transfer->type) {
-	case LIBUSB_TRANSFER_TYPE_CONTROL:
-		return submit_control_transfer(itransfer);
-	case LIBUSB_TRANSFER_TYPE_BULK:
-	case LIBUSB_TRANSFER_TYPE_INTERRUPT:
-		return submit_bulk_transfer(itransfer);
-	case LIBUSB_TRANSFER_TYPE_ISOCHRONOUS:
-		return submit_iso_transfer(itransfer);
-	default:
-		usbi_err(TRANSFER_CTX(transfer), "unknown endpoint type %d", transfer->type);
-		return LIBUSB_ERROR_INVALID_PARAM;
-	}
-}
-
-static int windows_abort_control(struct usbi_transfer *itransfer)
-{
-	struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	struct windows_device_priv *priv = _device_priv(transfer->dev_handle->dev);
-
-	return priv->apib->abort_control(itransfer);
-}
-
-static int windows_abort_transfers(struct usbi_transfer *itransfer)
-{
-	struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	struct windows_device_priv *priv = _device_priv(transfer->dev_handle->dev);
-
-	return priv->apib->abort_transfers(itransfer);
-}
-
-static int windows_cancel_transfer(struct usbi_transfer *itransfer)
-{
-	struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-#if defined(FORCE_INSTANT_TIMEOUTS)
-	struct windows_transfer_priv *transfer_priv = usbi_transfer_get_os_priv(itransfer);
-
-	// Forces instant overlapped completion on timeouts - use at your own risks
-	if (itransfer->flags & USBI_TRANSFER_TIMED_OUT) {
-		transfer_priv->pollable_fd.overlapped->Internal &= ~STATUS_PENDING;
-	}
-#endif
-	switch (transfer->type) {
-	case LIBUSB_TRANSFER_TYPE_CONTROL:
-		return windows_abort_control(itransfer);
-	case LIBUSB_TRANSFER_TYPE_BULK:
-	case LIBUSB_TRANSFER_TYPE_INTERRUPT:
-	case LIBUSB_TRANSFER_TYPE_ISOCHRONOUS:
-		return windows_abort_transfers(itransfer);
-	default:
-		usbi_err(ITRANSFER_CTX(itransfer), "unknown endpoint type %d", transfer->type);
-		return LIBUSB_ERROR_INVALID_PARAM;
-	}
-}
-
-static void windows_transfer_callback(struct usbi_transfer *itransfer, uint32_t io_result, uint32_t io_size)
-{
-	struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	struct windows_device_priv *priv = _device_priv(transfer->dev_handle->dev);
-	int status;
-
-	usbi_dbg("handling I/O completion with errcode %d", io_result);
-
-	switch(io_result) {
-	case NO_ERROR:
-		status = priv->apib->copy_transfer_data(itransfer, io_size);
-		break;
-	case ERROR_GEN_FAILURE:
-		usbi_dbg("detected endpoint stall");
-		status = LIBUSB_TRANSFER_STALL;
-		break;
-	case ERROR_SEM_TIMEOUT:
-		usbi_dbg("detected semaphore timeout");
-		status = LIBUSB_TRANSFER_TIMED_OUT;
-		break;
-	case ERROR_OPERATION_ABORTED:
-		if (itransfer->flags & USBI_TRANSFER_TIMED_OUT) {
-			usbi_dbg("detected timeout");
-			status = LIBUSB_TRANSFER_TIMED_OUT;
-		} else {
-			usbi_dbg("detected operation aborted");
-			status = LIBUSB_TRANSFER_CANCELLED;
-		}
-		break;
-	default:
-		usbi_err(ITRANSFER_CTX(itransfer), "detected I/O error: %s", windows_error_str(0));
-		status = LIBUSB_TRANSFER_ERROR;
-		break;
-	}
-	windows_clear_transfer_priv(itransfer);	// Cancel polling
-	usbi_handle_transfer_completion(itransfer, (enum libusb_transfer_status)status);
-}
-
-static void windows_handle_callback (struct usbi_transfer *itransfer, uint32_t io_result, uint32_t io_size)
-{
-	struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-
-	switch (transfer->type) {
-	case LIBUSB_TRANSFER_TYPE_CONTROL:
-	case LIBUSB_TRANSFER_TYPE_BULK:
-	case LIBUSB_TRANSFER_TYPE_INTERRUPT:
-	case LIBUSB_TRANSFER_TYPE_ISOCHRONOUS:
-		windows_transfer_callback (itransfer, io_result, io_size);
-		break;
-	default:
-		usbi_err(ITRANSFER_CTX(itransfer), "unknown endpoint type %d", transfer->type);
-	}
-}
-
-static int windows_handle_events(struct libusb_context *ctx, struct pollfd *fds, POLL_NFDS_TYPE nfds, int num_ready)
-{
-	struct windows_transfer_priv* transfer_priv = NULL;
-	POLL_NFDS_TYPE i = 0;
-	bool found = false;
-	struct usbi_transfer *transfer;
-	DWORD io_size, io_result;
-
-	usbi_mutex_lock(&ctx->open_devs_lock);
-	for (i = 0; i < nfds && num_ready > 0; i++) {
-
-		usbi_dbg("checking fd %d with revents = %04x", fds[i].fd, fds[i].revents);
-
-		if (!fds[i].revents) {
-			continue;
-		}
-
-		num_ready--;
-
-		// Because a Windows OVERLAPPED is used for poll emulation,
-		// a pollable fd is created and stored with each transfer
-		usbi_mutex_lock(&ctx->flying_transfers_lock);
-		list_for_each_entry(transfer, &ctx->flying_transfers, list, struct usbi_transfer) {
-			transfer_priv = usbi_transfer_get_os_priv(transfer);
-			if (transfer_priv->pollable_fd.fd == fds[i].fd) {
-				found = true;
-				break;
-			}
-		}
-		usbi_mutex_unlock(&ctx->flying_transfers_lock);
-
-		if (found) {
-			// Handle async requests that completed synchronously first
-			if (HasOverlappedIoCompletedSync(transfer_priv->pollable_fd.overlapped)) {
-				io_result = NO_ERROR;
-				io_size = (DWORD)transfer_priv->pollable_fd.overlapped->InternalHigh;
-			// Regular async overlapped
-			} else if (GetOverlappedResult(transfer_priv->pollable_fd.handle,
-				transfer_priv->pollable_fd.overlapped, &io_size, false)) {
-				io_result = NO_ERROR;
-			} else {
-				io_result = GetLastError();
-			}
-			usbi_remove_pollfd(ctx, transfer_priv->pollable_fd.fd);
-			// let handle_callback free the event using the transfer wfd
-			// If you don't use the transfer wfd, you run a risk of trying to free a
-			// newly allocated wfd that took the place of the one from the transfer.
-			windows_handle_callback(transfer, io_result, io_size);
-		} else {
-			usbi_err(ctx, "could not find a matching transfer for fd %x", fds[i]);
-			return LIBUSB_ERROR_NOT_FOUND;
-		}
-	}
-
-	usbi_mutex_unlock(&ctx->open_devs_lock);
-	return LIBUSB_SUCCESS;
-}
-
-/*
- * Monotonic and real time functions
- */
-unsigned __stdcall windows_clock_gettime_threaded(void* param)
-{
-	LARGE_INTEGER hires_counter, li_frequency;
-	LONG nb_responses;
-	int timer_index;
-
-	// Init - find out if we have access to a monotonic (hires) timer
-	if (!QueryPerformanceFrequency(&li_frequency)) {
-		usbi_dbg("no hires timer available on this platform");
-		hires_frequency = 0;
-		hires_ticks_to_ps = UINT64_C(0);
-	} else {
-		hires_frequency = li_frequency.QuadPart;
-		// The hires frequency can go as high as 4 GHz, so we'll use a conversion
-		// to picoseconds to compute the tv_nsecs part in clock_gettime
-		hires_ticks_to_ps = UINT64_C(1000000000000) / hires_frequency;
-		usbi_dbg("hires timer available (Frequency: %"PRIu64" Hz)", hires_frequency);
-	}
-
-	// Main loop - wait for requests
-	while (1) {
-		timer_index = WaitForMultipleObjects(2, timer_request, FALSE, INFINITE) - WAIT_OBJECT_0;
-		if ( (timer_index != 0) && (timer_index != 1) ) {
-			usbi_dbg("failure to wait on requests: %s", windows_error_str(0));
-			continue;
-		}
-		if (request_count[timer_index] == 0) {
-			// Request already handled
-			ResetEvent(timer_request[timer_index]);
-			// There's still a possiblity that a thread sends a request between the
-			// time we test request_count[] == 0 and we reset the event, in which case
-			// the request would be ignored. The simple solution to that is to test
-			// request_count again and process requests if non zero.
-			if (request_count[timer_index] == 0)
-				continue;
-		}
-		switch (timer_index) {
-		case 0:
-			WaitForSingleObject(timer_mutex, INFINITE);
-			// Requests to this thread are for hires always
-			if (QueryPerformanceCounter(&hires_counter) != 0) {
-				timer_tp.tv_sec = (long)(hires_counter.QuadPart / hires_frequency);
-				timer_tp.tv_nsec = (long)(((hires_counter.QuadPart % hires_frequency)/1000) * hires_ticks_to_ps);
-			} else {
-				// Fallback to real-time if we can't get monotonic value
-				// Note that real-time clock does not wait on the mutex or this thread.
-				windows_clock_gettime(USBI_CLOCK_REALTIME, &timer_tp);
-			}
-			ReleaseMutex(timer_mutex);
-
-			nb_responses = InterlockedExchange((LONG*)&request_count[0], 0);
-			if ( (nb_responses)
-			  && (ReleaseSemaphore(timer_response, nb_responses, NULL) == 0) ) {
-				usbi_dbg("unable to release timer semaphore %d: %s", windows_error_str(0));
-			}
-			continue;
-		case 1: // time to quit
-			usbi_dbg("timer thread quitting");
-			return 0;
-		}
-	}
-	usbi_dbg("ERROR: broken timer thread");
-	return 1;
-}
-
-static int windows_clock_gettime(int clk_id, struct timespec *tp)
-{
-	FILETIME filetime;
-	ULARGE_INTEGER rtime;
-	DWORD r;
-	switch(clk_id) {
-	case USBI_CLOCK_MONOTONIC:
-		if (hires_frequency != 0) {
-			while (1) {
-				InterlockedIncrement((LONG*)&request_count[0]);
-				SetEvent(timer_request[0]);
-				r = WaitForSingleObject(timer_response, TIMER_REQUEST_RETRY_MS);
-				switch(r) {
-				case WAIT_OBJECT_0:
-					WaitForSingleObject(timer_mutex, INFINITE);
-					*tp = timer_tp;
-					ReleaseMutex(timer_mutex);
-					return LIBUSB_SUCCESS;
-				case WAIT_TIMEOUT:
-					usbi_dbg("could not obtain a timer value within reasonable timeframe - too much load?");
-					break; // Retry until successful
-				default:
-					usbi_dbg("WaitForSingleObject failed: %s", windows_error_str(0));
-					return LIBUSB_ERROR_OTHER;
-				}
-			}
-		}
-		// Fall through and return real-time if monotonic was not detected @ timer init
-	case USBI_CLOCK_REALTIME:
-		// We follow http://msdn.microsoft.com/en-us/library/ms724928%28VS.85%29.aspx
-		// with a predef epoch_time to have an epoch that starts at 1970.01.01 00:00
-		// Note however that our resolution is bounded by the Windows system time
-		// functions and is at best of the order of 1 ms (or, usually, worse)
-		GetSystemTimeAsFileTime(&filetime);
-		rtime.LowPart = filetime.dwLowDateTime;
-		rtime.HighPart = filetime.dwHighDateTime;
-		rtime.QuadPart -= epoch_time;
-		tp->tv_sec = (long)(rtime.QuadPart / 10000000);
-		tp->tv_nsec = (long)((rtime.QuadPart % 10000000)*100);
-		return LIBUSB_SUCCESS;
-	default:
-		return LIBUSB_ERROR_INVALID_PARAM;
-	}
-}
-
-
-// NB: MSVC6 does not support named initializers.
-const struct usbi_os_backend windows_backend = {
-	"Windows",
-	windows_init,
-	windows_exit,
-
-	windows_get_device_list,
-	windows_open,
-	windows_close,
-
-	windows_get_device_descriptor,
-	windows_get_active_config_descriptor,
-	windows_get_config_descriptor,
-
-	windows_get_configuration,
-	windows_set_configuration,
-	windows_claim_interface,
-	windows_release_interface,
-
-	windows_set_interface_altsetting,
-	windows_clear_halt,
-	windows_reset_device,
-
-	windows_kernel_driver_active,
-	windows_detach_kernel_driver,
-	windows_attach_kernel_driver,
-
-	windows_destroy_device,
-
-	windows_submit_transfer,
-	windows_cancel_transfer,
-	windows_clear_transfer_priv,
-
-	windows_handle_events,
-
-	windows_clock_gettime,
-#if defined(USBI_TIMERFD_AVAILABLE)
-	NULL,
-#endif
-	sizeof(struct windows_device_priv),
-	sizeof(struct windows_device_handle_priv),
-	sizeof(struct windows_transfer_priv),
-	0,
-};
-
-
-/*
- * USB API backends
- */
-static int unsupported_init(struct libusb_context *ctx) {
-	return LIBUSB_SUCCESS;
-}
-static int unsupported_exit(void) {
-	return LIBUSB_SUCCESS;
-}
-static int unsupported_open(struct libusb_device_handle *dev_handle) {
-	PRINT_UNSUPPORTED_API(open);
-}
-static void unsupported_close(struct libusb_device_handle *dev_handle) {
-	usbi_dbg("unsupported API call for 'close'");
-}
-static int unsupported_claim_interface(struct libusb_device_handle *dev_handle, int iface) {
-	PRINT_UNSUPPORTED_API(claim_interface);
-}
-static int unsupported_set_interface_altsetting(struct libusb_device_handle *dev_handle, int iface, int altsetting) {
-	PRINT_UNSUPPORTED_API(set_interface_altsetting);
-}
-static int unsupported_release_interface(struct libusb_device_handle *dev_handle, int iface) {
-	PRINT_UNSUPPORTED_API(release_interface);
-}
-static int unsupported_clear_halt(struct libusb_device_handle *dev_handle, unsigned char endpoint) {
-	PRINT_UNSUPPORTED_API(clear_halt);
-}
-static int unsupported_reset_device(struct libusb_device_handle *dev_handle) {
-	PRINT_UNSUPPORTED_API(reset_device);
-}
-static int unsupported_submit_bulk_transfer(struct usbi_transfer *itransfer) {
-	PRINT_UNSUPPORTED_API(submit_bulk_transfer);
-}
-static int unsupported_submit_iso_transfer(struct usbi_transfer *itransfer) {
-	PRINT_UNSUPPORTED_API(submit_iso_transfer);
-}
-static int unsupported_submit_control_transfer(struct usbi_transfer *itransfer) {
-	PRINT_UNSUPPORTED_API(submit_control_transfer);
-}
-static int unsupported_abort_control(struct usbi_transfer *itransfer) {
-	PRINT_UNSUPPORTED_API(abort_control);
-}
-static int unsupported_abort_transfers(struct usbi_transfer *itransfer) {
-	PRINT_UNSUPPORTED_API(abort_transfers);
-}
-static int unsupported_copy_transfer_data(struct usbi_transfer *itransfer, uint32_t io_size) {
-	PRINT_UNSUPPORTED_API(copy_transfer_data);
-}
-
-// These names must be uppercase
-const char* hub_driver_names[] = {"USBHUB", "USBHUB3", "NUSB3HUB", "FLXHCIH", "TIHUB3", "ETRONHUB3", "VIAHUB3", "ASMTHUB3"};
-const char* composite_driver_names[] = {"USBCCGP"};
-const char* winusb_driver_names[] = {"WINUSB"};
-const struct windows_usb_api_backend usb_api_backend[USB_API_MAX] = {
-	{
-		USB_API_UNSUPPORTED,
-		"Unsupported API",
-		&CLASS_GUID_UNSUPPORTED,
-		NULL,
-		0,
-		unsupported_init,
-		unsupported_exit,
-		unsupported_open,
-		unsupported_close,
-		unsupported_claim_interface,
-		unsupported_set_interface_altsetting,
-		unsupported_release_interface,
-		unsupported_clear_halt,
-		unsupported_reset_device,
-		unsupported_submit_bulk_transfer,
-		unsupported_submit_iso_transfer,
-		unsupported_submit_control_transfer,
-		unsupported_abort_control,
-		unsupported_abort_transfers,
-		unsupported_copy_transfer_data,
-	}, {
-		USB_API_HUB,
-		"HUB API",
-		&CLASS_GUID_UNSUPPORTED,
-		hub_driver_names,
-		sizeof(hub_driver_names)/sizeof(hub_driver_names[0]),
-		unsupported_init,
-		unsupported_exit,
-		unsupported_open,
-		unsupported_close,
-		unsupported_claim_interface,
-		unsupported_set_interface_altsetting,
-		unsupported_release_interface,
-		unsupported_clear_halt,
-		unsupported_reset_device,
-		unsupported_submit_bulk_transfer,
-		unsupported_submit_iso_transfer,
-		unsupported_submit_control_transfer,
-		unsupported_abort_control,
-		unsupported_abort_transfers,
-		unsupported_copy_transfer_data,
-	}, {
-		USB_API_COMPOSITE,
-		"Composite API",
-		&CLASS_GUID_COMPOSITE,
-		composite_driver_names,
-		sizeof(composite_driver_names)/sizeof(composite_driver_names[0]),
-		composite_init,
-		composite_exit,
-		composite_open,
-		composite_close,
-		composite_claim_interface,
-		composite_set_interface_altsetting,
-		composite_release_interface,
-		composite_clear_halt,
-		composite_reset_device,
-		composite_submit_bulk_transfer,
-		composite_submit_iso_transfer,
-		composite_submit_control_transfer,
-		composite_abort_control,
-		composite_abort_transfers,
-		composite_copy_transfer_data,
-	}, {
-		USB_API_WINUSB,
-		"WinUSB API",
-		&CLASS_GUID_LIBUSB_WINUSB,
-		winusb_driver_names,
-		sizeof(winusb_driver_names)/sizeof(winusb_driver_names[0]),
-		winusb_init,
-		winusb_exit,
-		winusb_open,
-		winusb_close,
-		winusb_claim_interface,
-		winusb_set_interface_altsetting,
-		winusb_release_interface,
-		winusb_clear_halt,
-		winusb_reset_device,
-		winusb_submit_bulk_transfer,
-		unsupported_submit_iso_transfer,
-		winusb_submit_control_transfer,
-		winusb_abort_control,
-		winusb_abort_transfers,
-		winusb_copy_transfer_data,
-	},
-};
-
-
-/*
- * WinUSB API functions
- */
-static int winusb_init(struct libusb_context *ctx)
-{
-	DLL_LOAD(winusb.dll, WinUsb_Initialize, TRUE);
-	DLL_LOAD(winusb.dll, WinUsb_Free, TRUE);
-	DLL_LOAD(winusb.dll, WinUsb_GetAssociatedInterface, TRUE);
-	DLL_LOAD(winusb.dll, WinUsb_GetDescriptor, TRUE);
-	DLL_LOAD(winusb.dll, WinUsb_QueryInterfaceSettings, TRUE);
-	DLL_LOAD(winusb.dll, WinUsb_QueryDeviceInformation, TRUE);
-	DLL_LOAD(winusb.dll, WinUsb_SetCurrentAlternateSetting, TRUE);
-	DLL_LOAD(winusb.dll, WinUsb_GetCurrentAlternateSetting, TRUE);
-	DLL_LOAD(winusb.dll, WinUsb_QueryPipe, TRUE);
-	DLL_LOAD(winusb.dll, WinUsb_SetPipePolicy, TRUE);
-	DLL_LOAD(winusb.dll, WinUsb_GetPipePolicy, TRUE);
-	DLL_LOAD(winusb.dll, WinUsb_ReadPipe, TRUE);
-	DLL_LOAD(winusb.dll, WinUsb_WritePipe, TRUE);
-	DLL_LOAD(winusb.dll, WinUsb_ControlTransfer, TRUE);
-	DLL_LOAD(winusb.dll, WinUsb_ResetPipe, TRUE);
-	DLL_LOAD(winusb.dll, WinUsb_AbortPipe, TRUE);
-	DLL_LOAD(winusb.dll, WinUsb_FlushPipe, TRUE);
-
-	api_winusb_available = true;
-	return LIBUSB_SUCCESS;
-}
-
-static int winusb_exit(void)
-{
-	return LIBUSB_SUCCESS;
-}
-
-// NB: open and close must ensure that they only handle interface of
-// the right API type, as these functions can be called wholesale from
-// composite_open(), with interfaces belonging to different APIs
-static int winusb_open(struct libusb_device_handle *dev_handle)
-{
-	struct libusb_context *ctx = DEVICE_CTX(dev_handle->dev);
-	struct windows_device_priv *priv = _device_priv(dev_handle->dev);
-	struct windows_device_handle_priv *handle_priv = _device_handle_priv(dev_handle);
-
-	HANDLE file_handle;
-	int i;
-
-	CHECK_WINUSB_AVAILABLE;
-
-	// WinUSB requires a seperate handle for each interface
-	for (i = 0; i < USB_MAXINTERFACES; i++) {
-		if ( (priv->usb_interface[i].path != NULL)
-		  && (priv->usb_interface[i].apib->id == USB_API_WINUSB) ) {
-			file_handle = CreateFileA(priv->usb_interface[i].path, GENERIC_WRITE | GENERIC_READ, FILE_SHARE_WRITE | FILE_SHARE_READ,
-				NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL | FILE_FLAG_OVERLAPPED, NULL);
-			if (file_handle == INVALID_HANDLE_VALUE) {
-				usbi_err(ctx, "could not open device %s (interface %d): %s", priv->usb_interface[i].path, i, windows_error_str(0));
-				switch(GetLastError()) {
-				case ERROR_FILE_NOT_FOUND:	// The device was disconnected
-					return LIBUSB_ERROR_NO_DEVICE;
-				case ERROR_ACCESS_DENIED:
-					return LIBUSB_ERROR_ACCESS;
-				default:
-					return LIBUSB_ERROR_IO;
-				}
-			}
-			handle_priv->interface_handle[i].dev_handle = file_handle;
-		}
-	}
-
-	return LIBUSB_SUCCESS;
-}
-
-static void winusb_close(struct libusb_device_handle *dev_handle)
-{
-	struct windows_device_handle_priv *handle_priv = _device_handle_priv(dev_handle);
-	struct windows_device_priv *priv = _device_priv(dev_handle->dev);
-	HANDLE file_handle;
-	int i;
-
-	if (!api_winusb_available)
-		return;
-
-	for (i = 0; i < USB_MAXINTERFACES; i++) {
-		if (priv->usb_interface[i].apib->id == USB_API_WINUSB) {
-			file_handle = handle_priv->interface_handle[i].dev_handle;
-			if ( (file_handle != 0) && (file_handle != INVALID_HANDLE_VALUE)) {
-				CloseHandle(file_handle);
-			}
-		}
-	}
-}
-
-static int winusb_configure_endpoints(struct libusb_device_handle *dev_handle, int iface)
-{
-	struct windows_device_handle_priv *handle_priv = _device_handle_priv(dev_handle);
-	struct windows_device_priv *priv = _device_priv(dev_handle->dev);
-	HANDLE winusb_handle = handle_priv->interface_handle[iface].api_handle;
-	UCHAR policy;
-	ULONG timeout = 0;
-	uint8_t endpoint_address;
-	int i;
-
-	CHECK_WINUSB_AVAILABLE;
-
-	// With handle and enpoints set (in parent), we can setup the default pipe properties
-	// see http://download.microsoft.com/download/D/1/D/D1DD7745-426B-4CC3-A269-ABBBE427C0EF/DVC-T705_DDC08.pptx
-	for (i=-1; i<priv->usb_interface[iface].nb_endpoints; i++) {
-		endpoint_address =(i==-1)?0:priv->usb_interface[iface].endpoint[i];
-		if (!WinUsb_SetPipePolicy(winusb_handle, endpoint_address,
-			PIPE_TRANSFER_TIMEOUT, sizeof(ULONG), &timeout)) {
-			usbi_dbg("failed to set PIPE_TRANSFER_TIMEOUT for control endpoint %02X", endpoint_address);
-		}
-		if (i == -1) continue;	// Other policies don't apply to control endpoint
-		policy = false;
-		if (!WinUsb_SetPipePolicy(winusb_handle, endpoint_address,
-			SHORT_PACKET_TERMINATE, sizeof(UCHAR), &policy)) {
-			usbi_dbg("failed to disable SHORT_PACKET_TERMINATE for endpoint %02X", endpoint_address);
-		}
-		if (!WinUsb_SetPipePolicy(winusb_handle, endpoint_address,
-			IGNORE_SHORT_PACKETS, sizeof(UCHAR), &policy)) {
-			usbi_dbg("failed to disable IGNORE_SHORT_PACKETS for endpoint %02X", endpoint_address);
-		}
-		if (!WinUsb_SetPipePolicy(winusb_handle, endpoint_address,
-			ALLOW_PARTIAL_READS, sizeof(UCHAR), &policy)) {
-			usbi_dbg("failed to disable ALLOW_PARTIAL_READS for endpoint %02X", endpoint_address);
-		}
-		policy = true;
-		if (!WinUsb_SetPipePolicy(winusb_handle, endpoint_address,
-			AUTO_CLEAR_STALL, sizeof(UCHAR), &policy)) {
-			usbi_dbg("failed to enable AUTO_CLEAR_STALL for endpoint %02X", endpoint_address);
-		}
-	}
-
-	return LIBUSB_SUCCESS;
-}
-
-static int winusb_claim_interface(struct libusb_device_handle *dev_handle, int iface)
-{
-	struct libusb_context *ctx = DEVICE_CTX(dev_handle->dev);
-	struct windows_device_handle_priv *handle_priv = _device_handle_priv(dev_handle);
-	struct windows_device_priv *priv = _device_priv(dev_handle->dev);
-	bool is_using_usbccgp = (priv->apib->id == USB_API_COMPOSITE);
-	HANDLE file_handle, winusb_handle;
-
-	CHECK_WINUSB_AVAILABLE;
-
-	// If the device is composite, but using the default Windows composite parent driver (usbccgp)
-	// or if it's the first WinUSB interface, we get a handle through WinUsb_Initialize().
-	if ((is_using_usbccgp) || (iface == 0)) {
-		// composite device (independent interfaces) or interface 0
-		file_handle = handle_priv->interface_handle[iface].dev_handle;
-		if ((file_handle == 0) || (file_handle == INVALID_HANDLE_VALUE)) {
-			return LIBUSB_ERROR_NOT_FOUND;
-		}
-
-		if (!WinUsb_Initialize(file_handle, &winusb_handle)) {
-			usbi_err(ctx, "could not access interface %d: %s", iface, windows_error_str(0));
-			handle_priv->interface_handle[iface].api_handle = INVALID_HANDLE_VALUE;
-
-			switch(GetLastError()) {
-			case ERROR_BAD_COMMAND:	// The device was disconnected
-				return LIBUSB_ERROR_NO_DEVICE;
-			default:
-				usbi_err(ctx, "could not claim interface %d: %s", iface, windows_error_str(0));
-				return LIBUSB_ERROR_ACCESS;
-			}
-		}
-		handle_priv->interface_handle[iface].api_handle = winusb_handle;
-	} else {
-		// For all other interfaces, use WinUsb_GetAssociatedInterface()
-		winusb_handle = handle_priv->interface_handle[0].api_handle;
-		// It is a requirement for multiple interface devices using WinUSB that you
-		// must first claim the first interface before you claim any other
-		if ((winusb_handle == 0) || (winusb_handle == INVALID_HANDLE_VALUE)) {
-#if defined(AUTO_CLAIM)
-			file_handle = handle_priv->interface_handle[0].dev_handle;
-			if (WinUsb_Initialize(file_handle, &winusb_handle)) {
-				handle_priv->interface_handle[0].api_handle = winusb_handle;
-				usbi_warn(ctx, "auto-claimed interface 0 (required to claim %d with WinUSB)", iface);
-			} else {
-				usbi_warn(ctx, "failed to auto-claim interface 0 (required to claim %d with WinUSB)", iface);
-				return LIBUSB_ERROR_ACCESS;
-			}
-#else
-			usbi_warn(ctx, "you must claim interface 0 before you can claim %d with WinUSB", iface);
-			return LIBUSB_ERROR_ACCESS;
-#endif
-		}
-		if (!WinUsb_GetAssociatedInterface(winusb_handle, (UCHAR)(iface-1),
-			&handle_priv->interface_handle[iface].api_handle)) {
-			handle_priv->interface_handle[iface].api_handle = INVALID_HANDLE_VALUE;
-			switch(GetLastError()) {
-			case ERROR_NO_MORE_ITEMS:   // invalid iface
-				return LIBUSB_ERROR_NOT_FOUND;
-			case ERROR_BAD_COMMAND:     // The device was disconnected
-				return LIBUSB_ERROR_NO_DEVICE;
-			case ERROR_ALREADY_EXISTS:  // already claimed
-				return LIBUSB_ERROR_BUSY;
-			default:
-				usbi_err(ctx, "could not claim interface %d: %s", iface, windows_error_str(0));
-				return LIBUSB_ERROR_ACCESS;
-			}
-		}
-	}
-	usbi_dbg("claimed interface %d", iface);
-	handle_priv->active_interface = iface;
-
-	return LIBUSB_SUCCESS;
-}
-
-static int winusb_release_interface(struct libusb_device_handle *dev_handle, int iface)
-{
-	struct windows_device_handle_priv *handle_priv = _device_handle_priv(dev_handle);
-	HANDLE winusb_handle;
-
-	CHECK_WINUSB_AVAILABLE;
-
-	winusb_handle = handle_priv->interface_handle[iface].api_handle;
-	if ((winusb_handle == 0) || (winusb_handle == INVALID_HANDLE_VALUE)) {
-		return LIBUSB_ERROR_NOT_FOUND;
-	}
-
-	WinUsb_Free(winusb_handle);
-	handle_priv->interface_handle[iface].api_handle = INVALID_HANDLE_VALUE;
-
-	return LIBUSB_SUCCESS;
-}
-
-/*
- * Return the first valid interface (of the same API type), for control transfers
- */
-static int winusb_get_valid_interface(struct libusb_device_handle *dev_handle)
-{
-	struct windows_device_handle_priv *handle_priv = _device_handle_priv(dev_handle);
-	int i;
-
-	for (i=0; i<USB_MAXINTERFACES; i++) {
-		if ( (handle_priv->interface_handle[i].dev_handle != 0)
-		  && (handle_priv->interface_handle[i].dev_handle != INVALID_HANDLE_VALUE)
-		  && (handle_priv->interface_handle[i].api_handle != 0)
-		  && (handle_priv->interface_handle[i].api_handle != INVALID_HANDLE_VALUE) ) {
-			return i;
-		}
-	}
-	return -1;
-}
-
-/*
- * Lookup interface by endpoint address. -1 if not found
- */
-static int interface_by_endpoint(struct windows_device_priv *priv,
-	struct windows_device_handle_priv *handle_priv, uint8_t endpoint_address)
-{
-	int i, j;
-	for (i=0; i<USB_MAXINTERFACES; i++) {
-		if (handle_priv->interface_handle[i].api_handle == INVALID_HANDLE_VALUE)
-			continue;
-		if (handle_priv->interface_handle[i].api_handle == 0)
-			continue;
-		if (priv->usb_interface[i].endpoint == NULL)
-			continue;
-		for (j=0; j<priv->usb_interface[i].nb_endpoints; j++) {
-			if (priv->usb_interface[i].endpoint[j] == endpoint_address) {
-				return i;
-			}
-		}
-	}
-	return -1;
-}
-
-static int winusb_submit_control_transfer(struct usbi_transfer *itransfer)
-{
-	struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	struct libusb_context *ctx = DEVICE_CTX(transfer->dev_handle->dev);
-	struct windows_device_priv *priv = _device_priv(transfer->dev_handle->dev);
-	struct windows_transfer_priv *transfer_priv = (struct windows_transfer_priv*)usbi_transfer_get_os_priv(itransfer);
-	struct windows_device_handle_priv *handle_priv = _device_handle_priv(
-		transfer->dev_handle);
-	WINUSB_SETUP_PACKET *setup = (WINUSB_SETUP_PACKET *) transfer->buffer;
-	ULONG size;
-	HANDLE winusb_handle;
-	int current_interface;
-	struct winfd wfd;
-
-	CHECK_WINUSB_AVAILABLE;
-
-	transfer_priv->pollable_fd = INVALID_WINFD;
-	size = transfer->length - LIBUSB_CONTROL_SETUP_SIZE;
-
-	if (size > MAX_CTRL_BUFFER_LENGTH)
-		return LIBUSB_ERROR_INVALID_PARAM;
-
-	current_interface = winusb_get_valid_interface(transfer->dev_handle);
-	if (current_interface < 0) {
-#if defined(AUTO_CLAIM)
-		if (auto_claim(transfer, &current_interface, USB_API_WINUSB) != LIBUSB_SUCCESS) {
-			return LIBUSB_ERROR_NOT_FOUND;
-		}
-#else
-		usbi_warn(ctx, "no interface available for control transfer");
-		return LIBUSB_ERROR_NOT_FOUND;
-#endif
-	}
-
-	usbi_dbg("will use interface %d", current_interface);
-	winusb_handle = handle_priv->interface_handle[current_interface].api_handle;
-
-	wfd = usbi_create_fd(winusb_handle, _O_RDONLY);
-	// Always use the handle returned from usbi_create_fd (wfd.handle)
-	if (wfd.fd < 0) {
-		return LIBUSB_ERROR_NO_MEM;
-	}
-
-	// Sending of set configuration control requests from WinUSB creates issues
-	if ( ((setup->request_type & (0x03 << 5)) == LIBUSB_REQUEST_TYPE_STANDARD)
-	  && (setup->request == LIBUSB_REQUEST_SET_CONFIGURATION) ) {
-		if (setup->value != priv->active_config) {
-			usbi_warn(ctx, "cannot set configuration other than the default one");
-			usbi_free_fd(wfd.fd);
-			return LIBUSB_ERROR_INVALID_PARAM;
-		}
-		wfd.overlapped->Internal = STATUS_COMPLETED_SYNCHRONOUSLY;
-		wfd.overlapped->InternalHigh = 0;
-	} else {
-		if (!WinUsb_ControlTransfer(wfd.handle, *setup, transfer->buffer + LIBUSB_CONTROL_SETUP_SIZE, size, NULL, wfd.overlapped)) {
-			if(GetLastError() != ERROR_IO_PENDING) {
-				usbi_err(ctx, "WinUsb_ControlTransfer failed: %s", windows_error_str(0));
-				usbi_free_fd(wfd.fd);
-				return LIBUSB_ERROR_IO;
-			}
-		} else {
-			wfd.overlapped->Internal = STATUS_COMPLETED_SYNCHRONOUSLY;
-			wfd.overlapped->InternalHigh = (DWORD)size;
-		}
-	}
-
-	// Use priv_transfer to store data needed for async polling
-	transfer_priv->pollable_fd = wfd;
-	transfer_priv->interface_number = (uint8_t)current_interface;
-
-	return LIBUSB_SUCCESS;
-}
-
-static int winusb_set_interface_altsetting(struct libusb_device_handle *dev_handle, int iface, int altsetting)
-{
-	struct libusb_context *ctx = DEVICE_CTX(dev_handle->dev);
-	struct windows_device_handle_priv *handle_priv = _device_handle_priv(dev_handle);
-	HANDLE winusb_handle;
-
-	CHECK_WINUSB_AVAILABLE;
-
-	if (altsetting > 255) {
-		return LIBUSB_ERROR_INVALID_PARAM;
-	}
-
-	winusb_handle = handle_priv->interface_handle[iface].api_handle;
-	if ((winusb_handle == 0) || (winusb_handle == INVALID_HANDLE_VALUE)) {
-		usbi_err(ctx, "interface must be claimed first");
-		return LIBUSB_ERROR_NOT_FOUND;
-	}
-
-	if (!WinUsb_SetCurrentAlternateSetting(winusb_handle, (UCHAR)altsetting)) {
-		usbi_err(ctx, "WinUsb_SetCurrentAlternateSetting failed: %s", windows_error_str(0));
-		return LIBUSB_ERROR_IO;
-	}
-
-	return LIBUSB_SUCCESS;
-}
-
-static int winusb_submit_bulk_transfer(struct usbi_transfer *itransfer)
-{
-	struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	struct libusb_context *ctx = DEVICE_CTX(transfer->dev_handle->dev);
-	struct windows_transfer_priv *transfer_priv = (struct windows_transfer_priv*)usbi_transfer_get_os_priv(itransfer);
-	struct windows_device_handle_priv *handle_priv = _device_handle_priv(transfer->dev_handle);
-	struct windows_device_priv *priv = _device_priv(transfer->dev_handle->dev);
-	HANDLE winusb_handle;
-	bool direction_in, ret;
-	int current_interface;
-	struct winfd wfd;
-
-	CHECK_WINUSB_AVAILABLE;
-
-	transfer_priv->pollable_fd = INVALID_WINFD;
-
-	current_interface = interface_by_endpoint(priv, handle_priv, transfer->endpoint);
-	if (current_interface < 0) {
-		usbi_err(ctx, "unable to match endpoint to an open interface - cancelling transfer");
-		return LIBUSB_ERROR_NOT_FOUND;
-	}
-
-	usbi_dbg("matched endpoint %02X with interface %d", transfer->endpoint, current_interface);
-
-	winusb_handle = handle_priv->interface_handle[current_interface].api_handle;
-	direction_in = transfer->endpoint & LIBUSB_ENDPOINT_IN;
-
-	wfd = usbi_create_fd(winusb_handle, direction_in?_O_RDONLY:_O_WRONLY);
-	// Always use the handle returned from usbi_create_fd (wfd.handle)
-	if (wfd.fd < 0) {
-		return LIBUSB_ERROR_NO_MEM;
-	}
-
-	if (direction_in) {
-		usbi_dbg("reading %d bytes", transfer->length);
-		ret = WinUsb_ReadPipe(wfd.handle, transfer->endpoint, transfer->buffer, transfer->length, NULL, wfd.overlapped);
-	} else {
-		usbi_dbg("writing %d bytes", transfer->length);
-		ret = WinUsb_WritePipe(wfd.handle, transfer->endpoint, transfer->buffer, transfer->length, NULL, wfd.overlapped);
-	}
-	if (!ret) {
-		if(GetLastError() != ERROR_IO_PENDING) {
-			usbi_err(ctx, "WinUsb_Pipe Transfer failed: %s", windows_error_str(0));
-			usbi_free_fd(wfd.fd);
-			return LIBUSB_ERROR_IO;
-		}
-	} else {
-		wfd.overlapped->Internal = STATUS_COMPLETED_SYNCHRONOUSLY;
-		wfd.overlapped->InternalHigh = (DWORD)transfer->length;
-	}
-
-	transfer_priv->pollable_fd = wfd;
-	transfer_priv->interface_number = (uint8_t)current_interface;
-
-	return LIBUSB_SUCCESS;
-}
-
-static int winusb_clear_halt(struct libusb_device_handle *dev_handle, unsigned char endpoint)
-{
-	struct libusb_context *ctx = DEVICE_CTX(dev_handle->dev);
-	struct windows_device_handle_priv *handle_priv = _device_handle_priv(dev_handle);
-	struct windows_device_priv *priv = _device_priv(dev_handle->dev);
-	HANDLE winusb_handle;
-	int current_interface;
-
-	CHECK_WINUSB_AVAILABLE;
-
-	current_interface = interface_by_endpoint(priv, handle_priv, endpoint);
-	if (current_interface < 0) {
-		usbi_err(ctx, "unable to match endpoint to an open interface - cannot clear");
-		return LIBUSB_ERROR_NOT_FOUND;
-	}
-
-	usbi_dbg("matched endpoint %02X with interface %d", endpoint, current_interface);
-	winusb_handle = handle_priv->interface_handle[current_interface].api_handle;
-
-	if (!WinUsb_ResetPipe(winusb_handle, endpoint)) {
-		usbi_err(ctx, "WinUsb_ResetPipe failed: %s", windows_error_str(0));
-		return LIBUSB_ERROR_NO_DEVICE;
-	}
-
-	return LIBUSB_SUCCESS;
-}
-
-/*
- * from http://www.winvistatips.com/winusb-bugchecks-t335323.html (confirmed
- * through testing as well):
- * "You can not call WinUsb_AbortPipe on control pipe. You can possibly cancel
- * the control transfer using CancelIo"
- */
-static int winusb_abort_control(struct usbi_transfer *itransfer)
-{
-	// Cancelling of the I/O is done in the parent
-	return LIBUSB_SUCCESS;
-}
-
-static int winusb_abort_transfers(struct usbi_transfer *itransfer)
-{
-	struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	struct libusb_context *ctx = DEVICE_CTX(transfer->dev_handle->dev);
-	struct windows_device_handle_priv *handle_priv = _device_handle_priv(transfer->dev_handle);
-	struct windows_transfer_priv *transfer_priv = usbi_transfer_get_os_priv(itransfer);
-	HANDLE winusb_handle;
-	int current_interface;
-
-	CHECK_WINUSB_AVAILABLE;
-
-	current_interface = transfer_priv->interface_number;
-	if ((current_interface < 0) || (current_interface >= USB_MAXINTERFACES)) {
-		usbi_err(ctx, "program assertion failed: invalid interface_number");
-		return LIBUSB_ERROR_NOT_FOUND;
-	}
-	usbi_dbg("will use interface %d", current_interface);
-
-	winusb_handle = handle_priv->interface_handle[current_interface].api_handle;
-
-	if (!WinUsb_AbortPipe(winusb_handle, transfer->endpoint)) {
-		usbi_err(ctx, "WinUsb_AbortPipe failed: %s", windows_error_str(0));
-		return LIBUSB_ERROR_NO_DEVICE;
-	}
-
-	return LIBUSB_SUCCESS;
-}
-
-/*
- * from the "How to Use WinUSB to Communicate with a USB Device" Microsoft white paper
- * (http://www.microsoft.com/whdc/connect/usb/winusb_howto.mspx):
- * "WinUSB does not support host-initiated reset port and cycle port operations" and
- * IOCTL_INTERNAL_USB_CYCLE_PORT is only available in kernel mode and the
- * IOCTL_USB_HUB_CYCLE_PORT ioctl was removed from Vista => the best we can do is
- * cycle the pipes (and even then, the control pipe can not be reset using WinUSB)
- */
-// TODO (post hotplug): see if we can force eject the device and redetect it (reuse hotplug?)
-static int winusb_reset_device(struct libusb_device_handle *dev_handle)
-{
-	struct libusb_context *ctx = DEVICE_CTX(dev_handle->dev);
-	struct windows_device_handle_priv *handle_priv = _device_handle_priv(dev_handle);
-	struct windows_device_priv *priv = _device_priv(dev_handle->dev);
-	struct winfd wfd;
-	HANDLE winusb_handle;
-	int i, j;
-
-	CHECK_WINUSB_AVAILABLE;
-
-	// Reset any available pipe (except control)
-	for (i=0; i<USB_MAXINTERFACES; i++) {
-		winusb_handle = handle_priv->interface_handle[i].api_handle;
-		for (wfd = handle_to_winfd(winusb_handle); wfd.fd > 0;)
-		{
-			// Cancel any pollable I/O
-			usbi_remove_pollfd(ctx, wfd.fd);
-			usbi_free_fd(wfd.fd);
-			wfd = handle_to_winfd(winusb_handle);
-		}
-
-		if ( (winusb_handle != 0) && (winusb_handle != INVALID_HANDLE_VALUE)) {
-			for (j=0; j<priv->usb_interface[i].nb_endpoints; j++) {
-				usbi_dbg("resetting ep %02X", priv->usb_interface[i].endpoint[j]);
-				if (!WinUsb_AbortPipe(winusb_handle, priv->usb_interface[i].endpoint[j])) {
-					usbi_err(ctx, "WinUsb_AbortPipe (pipe address %02X) failed: %s",
-						priv->usb_interface[i].endpoint[j], windows_error_str(0));
-				}
-				// FlushPipe seems to fail on OUT pipes
-				if ( (priv->usb_interface[i].endpoint[j] & LIBUSB_ENDPOINT_IN)
-				  && (!WinUsb_FlushPipe(winusb_handle, priv->usb_interface[i].endpoint[j])) ) {
-					usbi_err(ctx, "WinUsb_FlushPipe (pipe address %02X) failed: %s",
-						priv->usb_interface[i].endpoint[j], windows_error_str(0));
-				}
-				if (!WinUsb_ResetPipe(winusb_handle, priv->usb_interface[i].endpoint[j])) {
-					usbi_err(ctx, "WinUsb_ResetPipe (pipe address %02X) failed: %s",
-						priv->usb_interface[i].endpoint[j], windows_error_str(0));
-				}
-			}
-		}
-	}
-
-	return LIBUSB_SUCCESS;
-}
-
-static int winusb_copy_transfer_data(struct usbi_transfer *itransfer, uint32_t io_size)
-{
-	itransfer->transferred += io_size;
-	return LIBUSB_TRANSFER_COMPLETED;
-}
-
-
-/*
- * Composite API functions
- */
-static int composite_init(struct libusb_context *ctx)
-{
-	return LIBUSB_SUCCESS;
-}
-
-static int composite_exit(void)
-{
-	return LIBUSB_SUCCESS;
-}
-
-static int composite_open(struct libusb_device_handle *dev_handle)
-{
-	struct windows_device_priv *priv = _device_priv(dev_handle->dev);
-	unsigned api;
-	int r;
-	uint8_t flag = 1<<USB_API_WINUSB;
-
-	for (api=USB_API_WINUSB; api<USB_API_MAX; api++) {
-		if (priv->composite_api_flags & flag) {
-			r = usb_api_backend[api].open(dev_handle);
-			if (r != LIBUSB_SUCCESS) {
-				return r;
-			}
-		}
-		flag <<= 1;
-	}
-	return LIBUSB_SUCCESS;
-}
-
-static void composite_close(struct libusb_device_handle *dev_handle)
-{
-	struct windows_device_priv *priv = _device_priv(dev_handle->dev);
-	unsigned api;
-	uint8_t flag = 1<<USB_API_WINUSB;
-
-	for (api=USB_API_WINUSB; api<USB_API_MAX; api++) {
-		if (priv->composite_api_flags & flag) {
-			usb_api_backend[api].close(dev_handle);
-		}
-		flag <<= 1;
-	}
-}
-
-static int composite_claim_interface(struct libusb_device_handle *dev_handle, int iface)
-{
-	struct windows_device_priv *priv = _device_priv(dev_handle->dev);
-	return priv->usb_interface[iface].apib->claim_interface(dev_handle, iface);
-}
-
-static int composite_set_interface_altsetting(struct libusb_device_handle *dev_handle, int iface, int altsetting)
-{
-	struct windows_device_priv *priv = _device_priv(dev_handle->dev);
-	return priv->usb_interface[iface].apib->set_interface_altsetting(dev_handle, iface, altsetting);
-}
-
-static int composite_release_interface(struct libusb_device_handle *dev_handle, int iface)
-{
-	struct windows_device_priv *priv = _device_priv(dev_handle->dev);
-	return priv->usb_interface[iface].apib->release_interface(dev_handle, iface);
-}
-
-static int composite_submit_control_transfer(struct usbi_transfer *itransfer)
-{
-	struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	struct libusb_context *ctx = DEVICE_CTX(transfer->dev_handle->dev);
-	struct windows_device_priv *priv = _device_priv(transfer->dev_handle->dev);
-	int i;
-
-	for (i=0; i<USB_MAXINTERFACES; i++) {
-		if (priv->usb_interface[i].path != NULL) {
-			usbi_dbg("using interface %d", i);
-			return priv->usb_interface[i].apib->submit_control_transfer(itransfer);
-		}
-	}
-
-	usbi_err(ctx, "no libusb supported interfaces to complete request");
-	return LIBUSB_ERROR_NOT_FOUND;
-}
-
-static int composite_submit_bulk_transfer(struct usbi_transfer *itransfer) {
-	struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	struct libusb_context *ctx = DEVICE_CTX(transfer->dev_handle->dev);
-	struct windows_device_handle_priv *handle_priv = _device_handle_priv(transfer->dev_handle);
-	struct windows_device_priv *priv = _device_priv(transfer->dev_handle->dev);
-	int current_interface;
-
-	current_interface = interface_by_endpoint(priv, handle_priv, transfer->endpoint);
-	if (current_interface < 0) {
-		usbi_err(ctx, "unable to match endpoint to an open interface - cancelling transfer");
-		return LIBUSB_ERROR_NOT_FOUND;
-	}
-
-	return priv->usb_interface[current_interface].apib->submit_bulk_transfer(itransfer);
-}
-
-static int composite_submit_iso_transfer(struct usbi_transfer *itransfer) {
-	struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	struct libusb_context *ctx = DEVICE_CTX(transfer->dev_handle->dev);
-	struct windows_device_handle_priv *handle_priv = _device_handle_priv(transfer->dev_handle);
-	struct windows_device_priv *priv = _device_priv(transfer->dev_handle->dev);
-	int current_interface;
-
-	current_interface = interface_by_endpoint(priv, handle_priv, transfer->endpoint);
-	if (current_interface < 0) {
-		usbi_err(ctx, "unable to match endpoint to an open interface - cancelling transfer");
-		return LIBUSB_ERROR_NOT_FOUND;
-	}
-
-	return priv->usb_interface[current_interface].apib->submit_iso_transfer(itransfer);
-}
-
-static int composite_clear_halt(struct libusb_device_handle *dev_handle, unsigned char endpoint)
-{
-	struct libusb_context *ctx = DEVICE_CTX(dev_handle->dev);
-	struct windows_device_handle_priv *handle_priv = _device_handle_priv(dev_handle);
-	struct windows_device_priv *priv = _device_priv(dev_handle->dev);
-	int current_interface;
-
-	current_interface = interface_by_endpoint(priv, handle_priv, endpoint);
-	if (current_interface < 0) {
-		usbi_err(ctx, "unable to match endpoint to an open interface - cannot clear");
-		return LIBUSB_ERROR_NOT_FOUND;
-	}
-
-	return priv->usb_interface[current_interface].apib->clear_halt(dev_handle, endpoint);
-}
-
-static int composite_abort_control(struct usbi_transfer *itransfer)
-{
-	struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	struct windows_transfer_priv *transfer_priv = usbi_transfer_get_os_priv(itransfer);
-	struct windows_device_priv *priv = _device_priv(transfer->dev_handle->dev);
-
-	return priv->usb_interface[transfer_priv->interface_number].apib->abort_control(itransfer);
-}
-
-static int composite_abort_transfers(struct usbi_transfer *itransfer)
-{
-	struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	struct windows_transfer_priv *transfer_priv = usbi_transfer_get_os_priv(itransfer);
-	struct windows_device_priv *priv = _device_priv(transfer->dev_handle->dev);
-
-	return priv->usb_interface[transfer_priv->interface_number].apib->abort_transfers(itransfer);
-}
-
-static int composite_reset_device(struct libusb_device_handle *dev_handle)
-{
-	struct windows_device_priv *priv = _device_priv(dev_handle->dev);
-	unsigned api;
-	int r;
-	uint8_t flag = 1<<USB_API_WINUSB;
-
-	for (api=USB_API_WINUSB; api<USB_API_MAX; api++) {
-		if (priv->composite_api_flags & flag) {
-			r = usb_api_backend[api].reset_device(dev_handle);
-			if (r != LIBUSB_SUCCESS) {
-				return r;
-			}
-		}
-		flag <<= 1;
-	}
-	return LIBUSB_SUCCESS;
-}
-
-static int composite_copy_transfer_data(struct usbi_transfer *itransfer, uint32_t io_size)
-{
-	struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
-	struct windows_transfer_priv *transfer_priv = usbi_transfer_get_os_priv(itransfer);
-	struct windows_device_priv *priv = _device_priv(transfer->dev_handle->dev);
-
-	return priv->usb_interface[transfer_priv->interface_number].apib->copy_transfer_data(itransfer, io_size);
-}
diff --git a/third_party/libusb/libusb/os/windows_usb.h b/third_party/libusb/libusb/os/windows_usb.h
deleted file mode 100644
index b629d18..0000000
--- a/third_party/libusb/libusb/os/windows_usb.h
+++ /dev/null
@@ -1,608 +0,0 @@
-/*
- * Windows backend for libusb 1.0
- * Copyright (C) 2009-2010 Pete Batard <pbatard@gmail.com>
- * With contributions from Michael Plante, Orin Eman et al.
- * Parts of this code adapted from libusb-win32-v1 by Stephan Meyer
- * Major code testing contribution by Xiaofan Chen
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#pragma once
-
-#if defined(_MSC_VER)
-// disable /W4 MSVC warnings that are benign
-#pragma warning(disable:4127) // conditional expression is constant
-#pragma warning(disable:4100) // unreferenced formal parameter
-#pragma warning(disable:4214) // bit field types other than int
-#pragma warning(disable:4201) // nameless struct/union
-#endif
-
-// Windows API default is uppercase - ugh!
-#if !defined(bool)
-#define bool BOOL
-#endif
-#if !defined(true)
-#define true TRUE
-#endif
-#if !defined(false)
-#define false FALSE
-#endif
-
-// Missing from MSVC6 setupapi.h
-#if !defined(SPDRP_ADDRESS)
-#define SPDRP_ADDRESS	28
-#endif
-#if !defined(SPDRP_INSTALL_STATE)
-#define SPDRP_INSTALL_STATE	34
-#endif
-
-#if defined(__CYGWIN__ )
-// cygwin produces a warning unless these prototypes are defined
-extern int _snprintf(char *buffer, size_t count, const char *format, ...);
-extern char *_strdup(const char *strSource);
-// _beginthreadex is MSVCRT => unavailable for cygwin. Fallback to using CreateThread
-#define _beginthreadex(a, b, c, d, e, f) CreateThread(a, b, (LPTHREAD_START_ROUTINE)c, d, e, f)
-#endif
-#define safe_free(p) do {if (p != NULL) {free((void*)p); p = NULL;}} while(0)
-#define safe_closehandle(h) do {if (h != INVALID_HANDLE_VALUE) {CloseHandle(h); h = INVALID_HANDLE_VALUE;}} while(0)
-#define safe_min(a, b) min((size_t)(a), (size_t)(b))
-#define safe_strcp(dst, dst_max, src, count) do {memcpy(dst, src, safe_min(count, dst_max)); \
-	((char*)dst)[safe_min(count, dst_max)-1] = 0;} while(0)
-#define safe_strcpy(dst, dst_max, src) safe_strcp(dst, dst_max, src, safe_strlen(src)+1)
-#define safe_strncat(dst, dst_max, src, count) strncat(dst, src, safe_min(count, dst_max - safe_strlen(dst) - 1))
-#define safe_strcat(dst, dst_max, src) safe_strncat(dst, dst_max, src, safe_strlen(src)+1)
-#define safe_strcmp(str1, str2) strcmp(((str1==NULL)?"<NULL>":str1), ((str2==NULL)?"<NULL>":str2))
-#define safe_strncmp(str1, str2, count) strncmp(((str1==NULL)?"<NULL>":str1), ((str2==NULL)?"<NULL>":str2), count)
-#define safe_strlen(str) ((str==NULL)?0:strlen(str))
-#define safe_sprintf _snprintf
-#define safe_unref_device(dev) do {if (dev != NULL) {libusb_unref_device(dev); dev = NULL;}} while(0)
-#define wchar_to_utf8_ms(wstr, str, strlen) WideCharToMultiByte(CP_UTF8, 0, wstr, -1, str, strlen, NULL, NULL)
-static inline void upperize(char* str) {
-	size_t i;
-	if (str == NULL) return;
-	for (i=0; i<safe_strlen(str); i++)
-		str[i] = (char)toupper((int)str[i]);
-}
-
-#define MAX_CTRL_BUFFER_LENGTH      4096
-#define MAX_USB_DEVICES             256
-#define MAX_USB_STRING_LENGTH       128
-#define MAX_GUID_STRING_LENGTH      40
-#define MAX_PATH_LENGTH             128
-#define MAX_KEY_LENGTH              256
-#define MAX_TIMER_SEMAPHORES        128
-#define TIMER_REQUEST_RETRY_MS      100
-#define ERR_BUFFER_SIZE             256
-#define LIST_SEPARATOR              ';'
-#define HTAB_SIZE                   1021
-
-// http://msdn.microsoft.com/en-us/library/ff545978.aspx
-// http://msdn.microsoft.com/en-us/library/ff545972.aspx
-// http://msdn.microsoft.com/en-us/library/ff545982.aspx
-#if !defined(GUID_DEVINTERFACE_USB_HOST_CONTROLLER)
-const GUID GUID_DEVINTERFACE_USB_HOST_CONTROLLER = { 0x3ABF6F2D, 0x71C4, 0x462A, {0x8A, 0x92, 0x1E, 0x68, 0x61, 0xE6, 0xAF, 0x27} };
-#endif
-#if !defined(GUID_DEVINTERFACE_USB_DEVICE)
-const GUID GUID_DEVINTERFACE_USB_DEVICE = { 0xA5DCBF10, 0x6530, 0x11D2, {0x90, 0x1F, 0x00, 0xC0, 0x4F, 0xB9, 0x51, 0xED} };
-#endif
-#if !defined(GUID_DEVINTERFACE_USB_HUB)
-const GUID GUID_DEVINTERFACE_USB_HUB = { 0xF18A0E88, 0xC30C, 0x11D0, {0x88, 0x15, 0x00, 0xA0, 0xC9, 0x06, 0xBE, 0xD8} };
-#endif
-const GUID GUID_NULL = { 0x00000000, 0x0000, 0x0000, {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00} };
-
-
-/*
- * Multiple USB API backend support
- */
-#define USB_API_UNSUPPORTED 0
-#define USB_API_HUB         1
-#define USB_API_COMPOSITE   2
-#define USB_API_WINUSB      3
-#define USB_API_MAX         4
-
-#define CLASS_GUID_UNSUPPORTED      GUID_NULL
-const GUID CLASS_GUID_LIBUSB_WINUSB = { 0x78A1C341, 0x4539, 0x11D3, {0xB8, 0x8D, 0x00, 0xC0, 0x4F, 0xAD, 0x51, 0x71} };
-const GUID CLASS_GUID_COMPOSITE     = { 0x36FC9E60, 0xC465, 0x11cF, {0x80, 0x56, 0x44, 0x45, 0x53, 0x54, 0x00, 0x00} };
-
-struct windows_usb_api_backend {
-	const uint8_t id;
-	const char* designation;
-	const GUID *class_guid;  // The Class GUID (for fallback in case the driver name cannot be read)
-	const char **driver_name_list; // Driver name, without .sys, e.g. "usbccgp"
-	const uint8_t nb_driver_names;
-	int (*init)(struct libusb_context *ctx);
-	int (*exit)(void);
-	int (*open)(struct libusb_device_handle *dev_handle);
-	void (*close)(struct libusb_device_handle *dev_handle);
-	int (*claim_interface)(struct libusb_device_handle *dev_handle, int iface);
-	int (*set_interface_altsetting)(struct libusb_device_handle *dev_handle, int iface, int altsetting);
-	int (*release_interface)(struct libusb_device_handle *dev_handle, int iface);
-	int (*clear_halt)(struct libusb_device_handle *dev_handle, unsigned char endpoint);
-	int (*reset_device)(struct libusb_device_handle *dev_handle);
-	int (*submit_bulk_transfer)(struct usbi_transfer *itransfer);
-	int (*submit_iso_transfer)(struct usbi_transfer *itransfer);
-	int (*submit_control_transfer)(struct usbi_transfer *itransfer);
-	int (*abort_control)(struct usbi_transfer *itransfer);
-	int (*abort_transfers)(struct usbi_transfer *itransfer);
-	int (*copy_transfer_data)(struct usbi_transfer *itransfer, uint32_t io_size);
-};
-
-extern const struct windows_usb_api_backend usb_api_backend[USB_API_MAX];
-
-#define PRINT_UNSUPPORTED_API(fname)              \
-	usbi_dbg("unsupported API call for '"         \
-		#fname "' (unrecognized device driver)"); \
-	return LIBUSB_ERROR_NOT_SUPPORTED;
-
-/*
- * private structures definition
- * with inline pseudo constructors/destructors
- */
-typedef struct libusb_device_descriptor USB_DEVICE_DESCRIPTOR, *PUSB_DEVICE_DESCRIPTOR;
-struct windows_device_priv {
-	uint8_t depth;						// distance to HCD
-	uint8_t port;						// port number on the hub
-	struct libusb_device *parent_dev;	// access to parent is required for usermode ops
-	char *path;							// device interface path
-	struct windows_usb_api_backend const *apib;
-	struct {
-		char *path;						// each interface needs a device interface path,
-		struct windows_usb_api_backend const *apib; // an API backend (multiple drivers support),
-		int8_t nb_endpoints;			// and a set of endpoint addresses (USB_MAXENDPOINTS)
-		uint8_t *endpoint;
-	} usb_interface[USB_MAXINTERFACES];
-	uint8_t composite_api_flags;		// composite devices require additional data
-	uint8_t active_config;
-	USB_DEVICE_DESCRIPTOR dev_descriptor;
-	unsigned char **config_descriptor;	// list of pointers to the cached config descriptors
-};
-
-static inline struct windows_device_priv *_device_priv(struct libusb_device *dev) {
-	return (struct windows_device_priv *)dev->os_priv;
-}
-
-static inline void windows_device_priv_init(libusb_device* dev) {
-	struct windows_device_priv* p = _device_priv(dev);
-	int i;
-	p->depth = 0;
-	p->port = 0;
-	p->parent_dev = NULL;
-	p->path = NULL;
-	p->apib = &usb_api_backend[USB_API_UNSUPPORTED];
-	p->composite_api_flags = 0;
-	p->active_config = 0;
-	p->config_descriptor = NULL;
-	memset(&(p->dev_descriptor), 0, sizeof(USB_DEVICE_DESCRIPTOR));
-	for (i=0; i<USB_MAXINTERFACES; i++) {
-		p->usb_interface[i].path = NULL;
-		p->usb_interface[i].apib = &usb_api_backend[USB_API_UNSUPPORTED];
-		p->usb_interface[i].nb_endpoints = 0;
-		p->usb_interface[i].endpoint = NULL;
-	}
-}
-
-static inline void windows_device_priv_release(libusb_device* dev) {
-	struct windows_device_priv* p = _device_priv(dev);
-	int i;
-	safe_free(p->path);
-	if ((dev->num_configurations > 0) && (p->config_descriptor != NULL)) {
-		for (i=0; i < dev->num_configurations; i++)
-			safe_free(p->config_descriptor[i]);
-	}
-	safe_free(p->config_descriptor);
-	for (i=0; i<USB_MAXINTERFACES; i++) {
-		safe_free(p->usb_interface[i].path);
-		safe_free(p->usb_interface[i].endpoint);
-	}
-}
-
-struct interface_handle_t {
-	HANDLE dev_handle; // WinUSB needs an extra handle for the file
-	HANDLE api_handle; // used by the API to communicate with the device
-};
-
-struct windows_device_handle_priv {
-	int active_interface;
-	struct interface_handle_t interface_handle[USB_MAXINTERFACES];
-#if defined(AUTO_CLAIM)
-	int autoclaim_count[USB_MAXINTERFACES]; // For auto-release
-#endif
-};
-
-static inline struct windows_device_handle_priv *_device_handle_priv(
-	struct libusb_device_handle *handle)
-{
-	return (struct windows_device_handle_priv *) handle->os_priv;
-}
-
-// used for async polling functions
-struct windows_transfer_priv {
-	struct winfd pollable_fd;
-	uint8_t interface_number;
-};
-
-// used to match a device driver (including filter drivers) against a supported API
-struct driver_lookup {
-	char list[MAX_KEY_LENGTH+1];// REG_MULTI_SZ list of services (driver) names
-	const DWORD reg_prop;		// SPDRP registry key to use to retreive list
-	const char* designation;	// internal designation (for debug output)
-};
-
-/*
- * API macros - from libusb-win32 1.x
- */
-#define DLL_DECLARE_PREFIXED(api, ret, prefix, name, args)    \
-	typedef ret (api * __dll_##name##_t)args;                 \
-	static __dll_##name##_t prefix##name = NULL
-
-#define DLL_LOAD_PREFIXED(dll, prefix, name, ret_on_failure)  \
-	do {                                                      \
-		HMODULE h = GetModuleHandleA(#dll);                   \
-	if (!h)                                                   \
-		h = LoadLibraryA(#dll);                               \
-	if (!h) {                                                 \
-		if (ret_on_failure) { return LIBUSB_ERROR_NOT_FOUND; }\
-		else { break; }                                       \
-	}                                                         \
-	prefix##name = (__dll_##name##_t)GetProcAddress(h, #name);\
-	if (prefix##name) break;                                  \
-	prefix##name = (__dll_##name##_t)GetProcAddress(h, #name "A");\
-	if (prefix##name) break;                                  \
-	prefix##name = (__dll_##name##_t)GetProcAddress(h, #name "W");\
-	if (prefix##name) break;                                  \
-	if(ret_on_failure)                                        \
-		return LIBUSB_ERROR_NOT_FOUND;                        \
-	} while(0)
-
-#define DLL_DECLARE(api, ret, name, args)   DLL_DECLARE_PREFIXED(api, ret, , name, args)
-#define DLL_LOAD(dll, name, ret_on_failure) DLL_LOAD_PREFIXED(dll, , name, ret_on_failure)
-
-/* OLE32 dependency */
-DLL_DECLARE_PREFIXED(WINAPI, HRESULT, p, CLSIDFromString, (LPCOLESTR, LPCLSID));
-
-/* SetupAPI dependencies */
-DLL_DECLARE_PREFIXED(WINAPI, HDEVINFO, p, SetupDiGetClassDevsA, (const GUID*, PCSTR, HWND, DWORD));
-DLL_DECLARE_PREFIXED(WINAPI, BOOL, p, SetupDiEnumDeviceInfo, (HDEVINFO, DWORD, PSP_DEVINFO_DATA));
-DLL_DECLARE_PREFIXED(WINAPI, BOOL, p, SetupDiEnumDeviceInterfaces, (HDEVINFO, PSP_DEVINFO_DATA,
-			const GUID*, DWORD, PSP_DEVICE_INTERFACE_DATA));
-DLL_DECLARE_PREFIXED(WINAPI, BOOL, p, SetupDiGetDeviceInterfaceDetailA, (HDEVINFO, PSP_DEVICE_INTERFACE_DATA,
-			PSP_DEVICE_INTERFACE_DETAIL_DATA_A, DWORD, PDWORD, PSP_DEVINFO_DATA));
-DLL_DECLARE_PREFIXED(WINAPI, BOOL, p, SetupDiDestroyDeviceInfoList, (HDEVINFO));
-DLL_DECLARE_PREFIXED(WINAPI, HKEY, p, SetupDiOpenDevRegKey, (HDEVINFO, PSP_DEVINFO_DATA, DWORD, DWORD, DWORD, REGSAM));
-DLL_DECLARE_PREFIXED(WINAPI, BOOL, p, SetupDiGetDeviceRegistryPropertyA, (HDEVINFO,
-			PSP_DEVINFO_DATA, DWORD, PDWORD, PBYTE, DWORD, PDWORD));
-DLL_DECLARE_PREFIXED(WINAPI, LONG, p, RegQueryValueExW, (HKEY, LPCWSTR, LPDWORD, LPDWORD, LPBYTE, LPDWORD));
-DLL_DECLARE_PREFIXED(WINAPI, LONG, p, RegCloseKey, (HKEY));
-
-/*
- * Windows DDK API definitions. Most of it copied from MinGW's includes
- */
-typedef DWORD DEVNODE, DEVINST;
-typedef DEVNODE *PDEVNODE, *PDEVINST;
-typedef DWORD RETURN_TYPE;
-typedef RETURN_TYPE CONFIGRET;
-
-#define CR_SUCCESS                              0x00000000
-#define CR_NO_SUCH_DEVNODE                      0x0000000D
-
-#define USB_DEVICE_DESCRIPTOR_TYPE              LIBUSB_DT_DEVICE
-#define USB_CONFIGURATION_DESCRIPTOR_TYPE       LIBUSB_DT_CONFIG
-#define USB_STRING_DESCRIPTOR_TYPE              LIBUSB_DT_STRING
-#define USB_INTERFACE_DESCRIPTOR_TYPE           LIBUSB_DT_INTERFACE
-#define USB_ENDPOINT_DESCRIPTOR_TYPE            LIBUSB_DT_ENDPOINT
-
-#define USB_REQUEST_GET_STATUS                  LIBUSB_REQUEST_GET_STATUS
-#define USB_REQUEST_CLEAR_FEATURE               LIBUSB_REQUEST_CLEAR_FEATURE
-#define USB_REQUEST_SET_FEATURE                 LIBUSB_REQUEST_SET_FEATURE
-#define USB_REQUEST_SET_ADDRESS                 LIBUSB_REQUEST_SET_ADDRESS
-#define USB_REQUEST_GET_DESCRIPTOR              LIBUSB_REQUEST_GET_DESCRIPTOR
-#define USB_REQUEST_SET_DESCRIPTOR              LIBUSB_REQUEST_SET_DESCRIPTOR
-#define USB_REQUEST_GET_CONFIGURATION           LIBUSB_REQUEST_GET_CONFIGURATION
-#define USB_REQUEST_SET_CONFIGURATION           LIBUSB_REQUEST_SET_CONFIGURATION
-#define USB_REQUEST_GET_INTERFACE               LIBUSB_REQUEST_GET_INTERFACE
-#define USB_REQUEST_SET_INTERFACE               LIBUSB_REQUEST_SET_INTERFACE
-#define USB_REQUEST_SYNC_FRAME                  LIBUSB_REQUEST_SYNCH_FRAME
-
-#define USB_GET_NODE_INFORMATION                258
-#define USB_GET_DESCRIPTOR_FROM_NODE_CONNECTION 260
-#define USB_GET_NODE_CONNECTION_NAME            261
-#define USB_GET_HUB_CAPABILITIES                271
-#if !defined(USB_GET_NODE_CONNECTION_INFORMATION_EX)
-#define USB_GET_NODE_CONNECTION_INFORMATION_EX  274
-#endif
-#if !defined(USB_GET_HUB_CAPABILITIES_EX)
-#define USB_GET_HUB_CAPABILITIES_EX             276
-#endif
-
-#ifndef METHOD_BUFFERED
-#define METHOD_BUFFERED                         0
-#endif
-#ifndef FILE_ANY_ACCESS
-#define FILE_ANY_ACCESS                         0x00000000
-#endif
-#ifndef FILE_DEVICE_UNKNOWN
-#define FILE_DEVICE_UNKNOWN                     0x00000022
-#endif
-#ifndef FILE_DEVICE_USB
-#define FILE_DEVICE_USB                         FILE_DEVICE_UNKNOWN
-#endif
-
-#ifndef CTL_CODE
-#define CTL_CODE(DeviceType, Function, Method, Access)( \
-  ((DeviceType) << 16) | ((Access) << 14) | ((Function) << 2) | (Method))
-#endif
-
-typedef enum USB_CONNECTION_STATUS {
-	NoDeviceConnected,
-	DeviceConnected,
-	DeviceFailedEnumeration,
-	DeviceGeneralFailure,
-	DeviceCausedOvercurrent,
-	DeviceNotEnoughPower,
-	DeviceNotEnoughBandwidth,
-	DeviceHubNestedTooDeeply,
-	DeviceInLegacyHub
-} USB_CONNECTION_STATUS, *PUSB_CONNECTION_STATUS;
-
-typedef enum USB_HUB_NODE {
-	UsbHub,
-	UsbMIParent
-} USB_HUB_NODE;
-
-/* Cfgmgr32.dll interface */
-DLL_DECLARE(WINAPI, CONFIGRET, CM_Get_Parent, (PDEVINST, DEVINST, ULONG));
-DLL_DECLARE(WINAPI, CONFIGRET, CM_Get_Child, (PDEVINST, DEVINST, ULONG));
-DLL_DECLARE(WINAPI, CONFIGRET, CM_Get_Sibling, (PDEVINST, DEVINST, ULONG));
-DLL_DECLARE(WINAPI, CONFIGRET, CM_Get_Device_IDA, (DEVINST, PCHAR, ULONG, ULONG));
-
-#define IOCTL_USB_GET_HUB_CAPABILITIES_EX \
-  CTL_CODE( FILE_DEVICE_USB, USB_GET_HUB_CAPABILITIES_EX, METHOD_BUFFERED, FILE_ANY_ACCESS)
-
-#define IOCTL_USB_GET_HUB_CAPABILITIES \
-  CTL_CODE(FILE_DEVICE_USB, USB_GET_HUB_CAPABILITIES, METHOD_BUFFERED, FILE_ANY_ACCESS)
-
-#define IOCTL_USB_GET_DESCRIPTOR_FROM_NODE_CONNECTION \
-  CTL_CODE(FILE_DEVICE_USB, USB_GET_DESCRIPTOR_FROM_NODE_CONNECTION, METHOD_BUFFERED, FILE_ANY_ACCESS)
-
-#define IOCTL_USB_GET_ROOT_HUB_NAME \
-  CTL_CODE(FILE_DEVICE_USB, HCD_GET_ROOT_HUB_NAME, METHOD_BUFFERED, FILE_ANY_ACCESS)
-
-#define IOCTL_USB_GET_NODE_INFORMATION \
-  CTL_CODE(FILE_DEVICE_USB, USB_GET_NODE_INFORMATION, METHOD_BUFFERED, FILE_ANY_ACCESS)
-
-#define IOCTL_USB_GET_NODE_CONNECTION_INFORMATION_EX \
-  CTL_CODE(FILE_DEVICE_USB, USB_GET_NODE_CONNECTION_INFORMATION_EX, METHOD_BUFFERED, FILE_ANY_ACCESS)
-
-#define IOCTL_USB_GET_NODE_CONNECTION_ATTRIBUTES \
-  CTL_CODE(FILE_DEVICE_USB, USB_GET_NODE_CONNECTION_ATTRIBUTES, METHOD_BUFFERED, FILE_ANY_ACCESS)
-
-#define IOCTL_USB_GET_NODE_CONNECTION_NAME \
-  CTL_CODE(FILE_DEVICE_USB, USB_GET_NODE_CONNECTION_NAME, METHOD_BUFFERED, FILE_ANY_ACCESS)
-
-// Most of the structures below need to be packed
-#pragma pack(push, 1)
-
-typedef struct USB_INTERFACE_DESCRIPTOR {
-  UCHAR  bLength;
-  UCHAR  bDescriptorType;
-  UCHAR  bInterfaceNumber;
-  UCHAR  bAlternateSetting;
-  UCHAR  bNumEndpoints;
-  UCHAR  bInterfaceClass;
-  UCHAR  bInterfaceSubClass;
-  UCHAR  bInterfaceProtocol;
-  UCHAR  iInterface;
-} USB_INTERFACE_DESCRIPTOR, *PUSB_INTERFACE_DESCRIPTOR;
-
-typedef struct USB_CONFIGURATION_DESCRIPTOR {
-  UCHAR  bLength;
-  UCHAR  bDescriptorType;
-  USHORT wTotalLength;
-  UCHAR  bNumInterfaces;
-  UCHAR  bConfigurationValue;
-  UCHAR  iConfiguration;
-  UCHAR  bmAttributes;
-  UCHAR  MaxPower;
-} USB_CONFIGURATION_DESCRIPTOR, *PUSB_CONFIGURATION_DESCRIPTOR;
-
-typedef struct USB_CONFIGURATION_DESCRIPTOR_SHORT {
-	struct {
-		ULONG ConnectionIndex;
-		struct {
-			UCHAR bmRequest;
-			UCHAR bRequest;
-			USHORT wValue;
-			USHORT wIndex;
-			USHORT wLength;
-		} SetupPacket;
-	} req;
-	USB_CONFIGURATION_DESCRIPTOR data;
-} USB_CONFIGURATION_DESCRIPTOR_SHORT;
-
-typedef struct USB_ENDPOINT_DESCRIPTOR {
-  UCHAR  bLength;
-  UCHAR  bDescriptorType;
-  UCHAR  bEndpointAddress;
-  UCHAR  bmAttributes;
-  USHORT  wMaxPacketSize;
-  UCHAR  bInterval;
-} USB_ENDPOINT_DESCRIPTOR, *PUSB_ENDPOINT_DESCRIPTOR;
-
-typedef struct USB_DESCRIPTOR_REQUEST {
-	ULONG  ConnectionIndex;
-	struct {
-		UCHAR  bmRequest;
-		UCHAR  bRequest;
-		USHORT  wValue;
-		USHORT  wIndex;
-		USHORT  wLength;
-	} SetupPacket;
-//	UCHAR  Data[0];
-} USB_DESCRIPTOR_REQUEST, *PUSB_DESCRIPTOR_REQUEST;
-
-typedef struct USB_HUB_DESCRIPTOR {
-	UCHAR  bDescriptorLength;
-	UCHAR  bDescriptorType;
-	UCHAR  bNumberOfPorts;
-	USHORT  wHubCharacteristics;
-	UCHAR  bPowerOnToPowerGood;
-	UCHAR  bHubControlCurrent;
-	UCHAR  bRemoveAndPowerMask[64];
-} USB_HUB_DESCRIPTOR, *PUSB_HUB_DESCRIPTOR;
-
-typedef struct USB_ROOT_HUB_NAME {
-	ULONG  ActualLength;
-	WCHAR  RootHubName[1];
-} USB_ROOT_HUB_NAME, *PUSB_ROOT_HUB_NAME;
-
-typedef struct USB_ROOT_HUB_NAME_FIXED {
-	ULONG ActualLength;
-	WCHAR RootHubName[MAX_PATH_LENGTH];
-} USB_ROOT_HUB_NAME_FIXED;
-
-typedef struct USB_NODE_CONNECTION_NAME {
-	ULONG  ConnectionIndex;
-	ULONG  ActualLength;
-	WCHAR  NodeName[1];
-} USB_NODE_CONNECTION_NAME, *PUSB_NODE_CONNECTION_NAME;
-
-typedef struct USB_NODE_CONNECTION_NAME_FIXED {
-	ULONG ConnectionIndex;
-	ULONG ActualLength;
-	WCHAR NodeName[MAX_PATH_LENGTH];
-} USB_NODE_CONNECTION_NAME_FIXED;
-
-typedef struct USB_HUB_NAME_FIXED {
-	union {
-		USB_ROOT_HUB_NAME_FIXED root;
-		USB_NODE_CONNECTION_NAME_FIXED node;
-	} u;
-} USB_HUB_NAME_FIXED;
-
-typedef struct USB_HUB_INFORMATION {
-	USB_HUB_DESCRIPTOR  HubDescriptor;
-	BOOLEAN  HubIsBusPowered;
-} USB_HUB_INFORMATION, *PUSB_HUB_INFORMATION;
-
-typedef struct USB_MI_PARENT_INFORMATION {
-  ULONG  NumberOfInterfaces;
-} USB_MI_PARENT_INFORMATION, *PUSB_MI_PARENT_INFORMATION;
-
-typedef struct USB_NODE_INFORMATION {
-	USB_HUB_NODE  NodeType;
-	union {
-		USB_HUB_INFORMATION  HubInformation;
-		USB_MI_PARENT_INFORMATION  MiParentInformation;
-	} u;
-} USB_NODE_INFORMATION, *PUSB_NODE_INFORMATION;
-
-typedef struct USB_PIPE_INFO {
-	USB_ENDPOINT_DESCRIPTOR  EndpointDescriptor;
-	ULONG  ScheduleOffset;
-} USB_PIPE_INFO, *PUSB_PIPE_INFO;
-
-typedef struct USB_NODE_CONNECTION_INFORMATION_EX {
-	ULONG  ConnectionIndex;
-	USB_DEVICE_DESCRIPTOR  DeviceDescriptor;
-	UCHAR  CurrentConfigurationValue;
-	UCHAR  Speed;
-	BOOLEAN  DeviceIsHub;
-	USHORT  DeviceAddress;
-	ULONG  NumberOfOpenPipes;
-	USB_CONNECTION_STATUS  ConnectionStatus;
-//	USB_PIPE_INFO  PipeList[0];
-} USB_NODE_CONNECTION_INFORMATION_EX, *PUSB_NODE_CONNECTION_INFORMATION_EX;
-
-typedef struct USB_HUB_CAP_FLAGS {
-	ULONG HubIsHighSpeedCapable:1;
-	ULONG HubIsHighSpeed:1;
-	ULONG HubIsMultiTtCapable:1;
-	ULONG HubIsMultiTt:1;
-	ULONG HubIsRoot:1;
-	ULONG HubIsArmedWakeOnConnect:1;
-	ULONG ReservedMBZ:26;
-} USB_HUB_CAP_FLAGS, *PUSB_HUB_CAP_FLAGS;
-
-typedef struct USB_HUB_CAPABILITIES {
-  ULONG  HubIs2xCapable : 1;
-} USB_HUB_CAPABILITIES, *PUSB_HUB_CAPABILITIES;
-
-typedef struct USB_HUB_CAPABILITIES_EX {
-	USB_HUB_CAP_FLAGS CapabilityFlags;
-} USB_HUB_CAPABILITIES_EX, *PUSB_HUB_CAPABILITIES_EX;
-
-#pragma pack(pop)
-
-/* winusb.dll interface */
-
-#define SHORT_PACKET_TERMINATE  0x01
-#define AUTO_CLEAR_STALL        0x02
-#define PIPE_TRANSFER_TIMEOUT   0x03
-#define IGNORE_SHORT_PACKETS    0x04
-#define ALLOW_PARTIAL_READS     0x05
-#define AUTO_FLUSH              0x06
-#define RAW_IO                  0x07
-#define MAXIMUM_TRANSFER_SIZE   0x08
-#define AUTO_SUSPEND            0x81
-#define SUSPEND_DELAY           0x83
-#define DEVICE_SPEED            0x01
-#define LowSpeed                0x01
-#define FullSpeed               0x02
-#define HighSpeed               0x03
-
-typedef enum USBD_PIPE_TYPE {
-	UsbdPipeTypeControl,
-	UsbdPipeTypeIsochronous,
-	UsbdPipeTypeBulk,
-	UsbdPipeTypeInterrupt
-} USBD_PIPE_TYPE;
-
-typedef struct {
-  USBD_PIPE_TYPE PipeType;
-  UCHAR          PipeId;
-  USHORT         MaximumPacketSize;
-  UCHAR          Interval;
-} WINUSB_PIPE_INFORMATION, *PWINUSB_PIPE_INFORMATION;
-
-#pragma pack(1)
-typedef struct {
-  UCHAR  request_type;
-  UCHAR  request;
-  USHORT value;
-  USHORT index;
-  USHORT length;
-} WINUSB_SETUP_PACKET, *PWINUSB_SETUP_PACKET;
-#pragma pack()
-
-typedef void *WINUSB_INTERFACE_HANDLE, *PWINUSB_INTERFACE_HANDLE;
-
-DLL_DECLARE(WINAPI, BOOL, WinUsb_Initialize, (HANDLE, PWINUSB_INTERFACE_HANDLE));
-DLL_DECLARE(WINAPI, BOOL, WinUsb_Free, (WINUSB_INTERFACE_HANDLE));
-DLL_DECLARE(WINAPI, BOOL, WinUsb_GetAssociatedInterface, (WINUSB_INTERFACE_HANDLE, UCHAR, PWINUSB_INTERFACE_HANDLE));
-DLL_DECLARE(WINAPI, BOOL, WinUsb_GetDescriptor, (WINUSB_INTERFACE_HANDLE, UCHAR, UCHAR, USHORT, PUCHAR, ULONG, PULONG));
-DLL_DECLARE(WINAPI, BOOL, WinUsb_QueryInterfaceSettings, (WINUSB_INTERFACE_HANDLE, UCHAR, PUSB_INTERFACE_DESCRIPTOR));
-DLL_DECLARE(WINAPI, BOOL, WinUsb_QueryDeviceInformation, (WINUSB_INTERFACE_HANDLE, ULONG, PULONG, PVOID));
-DLL_DECLARE(WINAPI, BOOL, WinUsb_SetCurrentAlternateSetting, (WINUSB_INTERFACE_HANDLE, UCHAR));
-DLL_DECLARE(WINAPI, BOOL, WinUsb_GetCurrentAlternateSetting, (WINUSB_INTERFACE_HANDLE, PUCHAR));
-DLL_DECLARE(WINAPI, BOOL, WinUsb_QueryPipe, (WINUSB_INTERFACE_HANDLE, UCHAR, UCHAR, PWINUSB_PIPE_INFORMATION));
-DLL_DECLARE(WINAPI, BOOL, WinUsb_SetPipePolicy, (WINUSB_INTERFACE_HANDLE, UCHAR, ULONG, ULONG, PVOID));
-DLL_DECLARE(WINAPI, BOOL, WinUsb_GetPipePolicy, (WINUSB_INTERFACE_HANDLE, UCHAR, ULONG, PULONG, PVOID));
-DLL_DECLARE(WINAPI, BOOL, WinUsb_ReadPipe, (WINUSB_INTERFACE_HANDLE, UCHAR, PUCHAR, ULONG, PULONG, LPOVERLAPPED));
-DLL_DECLARE(WINAPI, BOOL, WinUsb_WritePipe, (WINUSB_INTERFACE_HANDLE, UCHAR, PUCHAR, ULONG, PULONG, LPOVERLAPPED));
-DLL_DECLARE(WINAPI, BOOL, WinUsb_ControlTransfer, (WINUSB_INTERFACE_HANDLE, WINUSB_SETUP_PACKET, PUCHAR, ULONG, PULONG, LPOVERLAPPED));
-DLL_DECLARE(WINAPI, BOOL, WinUsb_ResetPipe, (WINUSB_INTERFACE_HANDLE, UCHAR));
-DLL_DECLARE(WINAPI, BOOL, WinUsb_AbortPipe, (WINUSB_INTERFACE_HANDLE, UCHAR));
-DLL_DECLARE(WINAPI, BOOL, WinUsb_FlushPipe, (WINUSB_INTERFACE_HANDLE, UCHAR));
diff --git a/third_party/libusb/libusb/sync.c b/third_party/libusb/libusb/sync.c
deleted file mode 100644
index 8eed47b..0000000
--- a/third_party/libusb/libusb/sync.c
+++ /dev/null
@@ -1,314 +0,0 @@
-/*
- * Synchronous I/O functions for libusb
- * Copyright (C) 2007-2008 Daniel Drake <dsd@gentoo.org>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#include <config.h>
-#include <errno.h>
-#include <stdint.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include "libusbi.h"
-
-/**
- * @defgroup syncio Synchronous device I/O
- *
- * This page documents libusb's synchronous (blocking) API for USB device I/O.
- * This interface is easy to use but has some limitations. More advanced users
- * may wish to consider using the \ref asyncio "asynchronous I/O API" instead.
- */
-
-static void LIBUSB_CALL ctrl_transfer_cb(struct libusb_transfer *transfer)
-{
-	int *completed = transfer->user_data;
-	*completed = 1;
-	usbi_dbg("actual_length=%d", transfer->actual_length);
-	/* caller interprets result and frees transfer */
-}
-
-/** \ingroup syncio
- * Perform a USB control transfer.
- *
- * The direction of the transfer is inferred from the bmRequestType field of
- * the setup packet.
- *
- * The wValue, wIndex and wLength fields values should be given in host-endian
- * byte order.
- *
- * \param dev_handle a handle for the device to communicate with
- * \param bmRequestType the request type field for the setup packet
- * \param bRequest the request field for the setup packet
- * \param wValue the value field for the setup packet
- * \param wIndex the index field for the setup packet
- * \param data a suitably-sized data buffer for either input or output
- * (depending on direction bits within bmRequestType)
- * \param wLength the length field for the setup packet. The data buffer should
- * be at least this size.
- * \param timeout timeout (in millseconds) that this function should wait
- * before giving up due to no response being received. For an unlimited
- * timeout, use value 0.
- * \returns on success, the number of bytes actually transferred
- * \returns LIBUSB_ERROR_TIMEOUT if the transfer timed out
- * \returns LIBUSB_ERROR_PIPE if the control request was not supported by the
- * device
- * \returns LIBUSB_ERROR_NO_DEVICE if the device has been disconnected
- * \returns another LIBUSB_ERROR code on other failures
- */
-int API_EXPORTED libusb_control_transfer(libusb_device_handle *dev_handle,
-	uint8_t bmRequestType, uint8_t bRequest, uint16_t wValue, uint16_t wIndex,
-	unsigned char *data, uint16_t wLength, unsigned int timeout)
-{
-	struct libusb_transfer *transfer = libusb_alloc_transfer(0);
-	unsigned char *buffer;
-	int completed = 0;
-	int r;
-
-	if (!transfer)
-		return LIBUSB_ERROR_NO_MEM;
-
-	buffer = malloc(LIBUSB_CONTROL_SETUP_SIZE + wLength);
-	if (!buffer) {
-		libusb_free_transfer(transfer);
-		return LIBUSB_ERROR_NO_MEM;
-	}
-
-	libusb_fill_control_setup(buffer, bmRequestType, bRequest, wValue, wIndex,
-		wLength);
-	if ((bmRequestType & LIBUSB_ENDPOINT_DIR_MASK) == LIBUSB_ENDPOINT_OUT)
-		memcpy(buffer + LIBUSB_CONTROL_SETUP_SIZE, data, wLength);
-
-	libusb_fill_control_transfer(transfer, dev_handle, buffer,
-		ctrl_transfer_cb, &completed, timeout);
-	transfer->flags = LIBUSB_TRANSFER_FREE_BUFFER;
-	r = libusb_submit_transfer(transfer);
-	if (r < 0) {
-		libusb_free_transfer(transfer);
-		return r;
-	}
-
-	while (!completed) {
-		r = libusb_handle_events_completed(HANDLE_CTX(dev_handle), &completed);
-		if (r < 0) {
-			if (r == LIBUSB_ERROR_INTERRUPTED)
-				continue;
-			libusb_cancel_transfer(transfer);
-			while (!completed)
-				if (libusb_handle_events_completed(HANDLE_CTX(dev_handle), &completed) < 0)
-					break;
-			libusb_free_transfer(transfer);
-			return r;
-		}
-	}
-
-	if ((bmRequestType & LIBUSB_ENDPOINT_DIR_MASK) == LIBUSB_ENDPOINT_IN)
-		memcpy(data, libusb_control_transfer_get_data(transfer),
-			transfer->actual_length);
-
-	switch (transfer->status) {
-	case LIBUSB_TRANSFER_COMPLETED:
-		r = transfer->actual_length;
-		break;
-	case LIBUSB_TRANSFER_TIMED_OUT:
-		r = LIBUSB_ERROR_TIMEOUT;
-		break;
-	case LIBUSB_TRANSFER_STALL:
-		r = LIBUSB_ERROR_PIPE;
-		break;
-	case LIBUSB_TRANSFER_NO_DEVICE:
-		r = LIBUSB_ERROR_NO_DEVICE;
-		break;
-	case LIBUSB_TRANSFER_OVERFLOW:
-		r = LIBUSB_ERROR_OVERFLOW;
-		break;
-	default:
-		usbi_warn(HANDLE_CTX(dev_handle),
-			"unrecognised status code %d", transfer->status);
-		r = LIBUSB_ERROR_OTHER;
-	}
-
-	libusb_free_transfer(transfer);
-	return r;
-}
-
-static void LIBUSB_CALL bulk_transfer_cb(struct libusb_transfer *transfer)
-{
-	int *completed = transfer->user_data;
-	*completed = 1;
-	usbi_dbg("actual_length=%d", transfer->actual_length);
-	/* caller interprets results and frees transfer */
-}
-
-static int do_sync_bulk_transfer(struct libusb_device_handle *dev_handle,
-	unsigned char endpoint, unsigned char *buffer, int length,
-	int *transferred, unsigned int timeout, unsigned char type)
-{
-	struct libusb_transfer *transfer = libusb_alloc_transfer(0);
-	int completed = 0;
-	int r;
-
-	if (!transfer)
-		return LIBUSB_ERROR_NO_MEM;
-
-	libusb_fill_bulk_transfer(transfer, dev_handle, endpoint, buffer, length,
-		bulk_transfer_cb, &completed, timeout);
-	transfer->type = type;
-
-	r = libusb_submit_transfer(transfer);
-	if (r < 0) {
-		libusb_free_transfer(transfer);
-		return r;
-	}
-
-	while (!completed) {
-		r = libusb_handle_events_completed(HANDLE_CTX(dev_handle), &completed);
-		if (r < 0) {
-			if (r == LIBUSB_ERROR_INTERRUPTED)
-				continue;
-			libusb_cancel_transfer(transfer);
-			while (!completed)
-				if (libusb_handle_events_completed(HANDLE_CTX(dev_handle), &completed) < 0)
-					break;
-			libusb_free_transfer(transfer);
-			return r;
-		}
-	}
-
-	*transferred = transfer->actual_length;
-	switch (transfer->status) {
-	case LIBUSB_TRANSFER_COMPLETED:
-		r = 0;
-		break;
-	case LIBUSB_TRANSFER_TIMED_OUT:
-		r = LIBUSB_ERROR_TIMEOUT;
-		break;
-	case LIBUSB_TRANSFER_STALL:
-		r = LIBUSB_ERROR_PIPE;
-		break;
-	case LIBUSB_TRANSFER_OVERFLOW:
-		r = LIBUSB_ERROR_OVERFLOW;
-		break;
-	case LIBUSB_TRANSFER_NO_DEVICE:
-		r = LIBUSB_ERROR_NO_DEVICE;
-		break;
-	default:
-		usbi_warn(HANDLE_CTX(dev_handle),
-			"unrecognised status code %d", transfer->status);
-		r = LIBUSB_ERROR_OTHER;
-	}
-
-	libusb_free_transfer(transfer);
-	return r;
-}
-
-/** \ingroup syncio
- * Perform a USB bulk transfer. The direction of the transfer is inferred from
- * the direction bits of the endpoint address.
- *
- * For bulk reads, the <tt>length</tt> field indicates the maximum length of
- * data you are expecting to receive. If less data arrives than expected,
- * this function will return that data, so be sure to check the
- * <tt>transferred</tt> output parameter.
- *
- * You should also check the <tt>transferred</tt> parameter for bulk writes.
- * Not all of the data may have been written.
- *
- * Also check <tt>transferred</tt> when dealing with a timeout error code.
- * libusb may have to split your transfer into a number of chunks to satisfy
- * underlying O/S requirements, meaning that the timeout may expire after
- * the first few chunks have completed. libusb is careful not to lose any data
- * that may have been transferred; do not assume that timeout conditions
- * indicate a complete lack of I/O.
- *
- * \param dev_handle a handle for the device to communicate with
- * \param endpoint the address of a valid endpoint to communicate with
- * \param data a suitably-sized data buffer for either input or output
- * (depending on endpoint)
- * \param length for bulk writes, the number of bytes from data to be sent. for
- * bulk reads, the maximum number of bytes to receive into the data buffer.
- * \param transferred output location for the number of bytes actually
- * transferred.
- * \param timeout timeout (in millseconds) that this function should wait
- * before giving up due to no response being received. For an unlimited
- * timeout, use value 0.
- *
- * \returns 0 on success (and populates <tt>transferred</tt>)
- * \returns LIBUSB_ERROR_TIMEOUT if the transfer timed out (and populates
- * <tt>transferred</tt>)
- * \returns LIBUSB_ERROR_PIPE if the endpoint halted
- * \returns LIBUSB_ERROR_OVERFLOW if the device offered more data, see
- * \ref packetoverflow
- * \returns LIBUSB_ERROR_NO_DEVICE if the device has been disconnected
- * \returns another LIBUSB_ERROR code on other failures
- */
-int API_EXPORTED libusb_bulk_transfer(struct libusb_device_handle *dev_handle,
-	unsigned char endpoint, unsigned char *data, int length, int *transferred,
-	unsigned int timeout)
-{
-	return do_sync_bulk_transfer(dev_handle, endpoint, data, length,
-		transferred, timeout, LIBUSB_TRANSFER_TYPE_BULK);
-}
-
-/** \ingroup syncio
- * Perform a USB interrupt transfer. The direction of the transfer is inferred
- * from the direction bits of the endpoint address.
- *
- * For interrupt reads, the <tt>length</tt> field indicates the maximum length
- * of data you are expecting to receive. If less data arrives than expected,
- * this function will return that data, so be sure to check the
- * <tt>transferred</tt> output parameter.
- *
- * You should also check the <tt>transferred</tt> parameter for interrupt
- * writes. Not all of the data may have been written.
- *
- * Also check <tt>transferred</tt> when dealing with a timeout error code.
- * libusb may have to split your transfer into a number of chunks to satisfy
- * underlying O/S requirements, meaning that the timeout may expire after
- * the first few chunks have completed. libusb is careful not to lose any data
- * that may have been transferred; do not assume that timeout conditions
- * indicate a complete lack of I/O.
- *
- * The default endpoint bInterval value is used as the polling interval.
- *
- * \param dev_handle a handle for the device to communicate with
- * \param endpoint the address of a valid endpoint to communicate with
- * \param data a suitably-sized data buffer for either input or output
- * (depending on endpoint)
- * \param length for bulk writes, the number of bytes from data to be sent. for
- * bulk reads, the maximum number of bytes to receive into the data buffer.
- * \param transferred output location for the number of bytes actually
- * transferred.
- * \param timeout timeout (in millseconds) that this function should wait
- * before giving up due to no response being received. For an unlimited
- * timeout, use value 0.
- *
- * \returns 0 on success (and populates <tt>transferred</tt>)
- * \returns LIBUSB_ERROR_TIMEOUT if the transfer timed out
- * \returns LIBUSB_ERROR_PIPE if the endpoint halted
- * \returns LIBUSB_ERROR_OVERFLOW if the device offered more data, see
- * \ref packetoverflow
- * \returns LIBUSB_ERROR_NO_DEVICE if the device has been disconnected
- * \returns another LIBUSB_ERROR code on other error
- */
-int API_EXPORTED libusb_interrupt_transfer(
-	struct libusb_device_handle *dev_handle, unsigned char endpoint,
-	unsigned char *data, int length, int *transferred, unsigned int timeout)
-{
-	return do_sync_bulk_transfer(dev_handle, endpoint, data, length,
-		transferred, timeout, LIBUSB_TRANSFER_TYPE_INTERRUPT);
-}
-
diff --git a/third_party/libusb/libusb/version.h b/third_party/libusb/libusb/version.h
deleted file mode 100644
index 08e2c872..0000000
--- a/third_party/libusb/libusb/version.h
+++ /dev/null
@@ -1,18 +0,0 @@
-/* This file is parsed by m4 and windres and RC.EXE so please keep it simple. */
-#ifndef LIBUSB_MAJOR
-#define LIBUSB_MAJOR 1
-#endif
-#ifndef LIBUSB_MINOR
-#define LIBUSB_MINOR 0
-#endif
-#ifndef LIBUSB_MICRO
-#define LIBUSB_MICRO 9
-#endif
-/* LIBUSB_NANO may be used for Windows internal versioning. 0 means unused. */
-#ifndef LIBUSB_NANO
-#define LIBUSB_NANO 0
-#endif
-/* LIBUSB_RC is the release candidate suffix. Should normally be empty. */
-#ifndef LIBUSB_RC
-#define LIBUSB_RC "-rc3"
-#endif
diff --git a/third_party/libusb/msvc/config.h b/third_party/libusb/msvc/config.h
deleted file mode 100644
index 9ac6134..0000000
--- a/third_party/libusb/msvc/config.h
+++ /dev/null
@@ -1,23 +0,0 @@
-/* config.h.  Manual config for MSVC.  */
-
-#ifndef _MSC_VER
-#warn "msvc/config.h shouldn't be included for your development environment."
-#error "Please make sure the msvc/ directory is removed from your build path."
-#endif
-
-/* Default visibility */
-#define DEFAULT_VISIBILITY /**/
-
-/* Debug message logging */
-//#define ENABLE_DEBUG_LOGGING 1
-
-/* Message logging */
-#define ENABLE_LOGGING 1
-
-/* Windows backend */
-#define OS_WINDOWS 1
-
-/* type of second poll() argument */
-#define POLL_NFDS_TYPE unsigned int
-
-#include <Winsock2.h>
diff --git a/third_party/libusb/msvc/ddk_build.cmd b/third_party/libusb/msvc/ddk_build.cmd
deleted file mode 100644
index fa79b82..0000000
--- a/third_party/libusb/msvc/ddk_build.cmd
+++ /dev/null
@@ -1,106 +0,0 @@
-@rem default builds static library.
-@rem you can pass the following arguments (case insensitive):
-@rem - "DLL" to build a DLL instead of a static library
-@rem - "/MT" to build a static library compatible with MSVC's /MT option (LIBCMT vs MSVCRT)
-@echo off
-
-if Test%BUILD_ALT_DIR%==Test goto usage
-
-rem process commandline parameters
-set TARGET=LIBRARY
-set STATIC_LIBC=
-set version=1.0
-
-if "%1" == "" goto no_more_args
-rem /I for case insensitive
-if /I Test%1==TestDLL set TARGET=DYNLINK
-if /I Test%1==Test/MT set STATIC_LIBC=1
-:no_more_args
-
-cd ..\libusb\os
-echo TARGETTYPE=%TARGET% > target
-copy target+..\..\msvc\libusb_sources sources >NUL 2>&1
-del target
-@echo on
-build -cwgZ
-@echo off
-if errorlevel 1 goto builderror
-cd ..\..
-
-set cpudir=i386
-set destType=Win32
-if %_BUILDARCH%==x86 goto isI386
-set cpudir=amd64
-set destType=x64
-:isI386
-
-set srcPath=libusb\os\obj%BUILD_ALT_DIR%\%cpudir%
-
-set dstPath=%destType%\Debug
-if %DDKBUILDENV%==chk goto isDebug
-set dstPath=%destType%\Release
-:isDebug
-
-if exist %destType% goto md2
-mkdir %destType%
-:md2
-if exist %dstPath% goto md3
-mkdir %dstPath%
-:md3
-if exist %dstPath%\dll goto md4
-mkdir %dstPath%\dll
-:md4
-if exist %dstPath%\lib goto md5
-md %dstPath%\lib
-:md5
-if exist %dstPath%\examples goto md6
-md %dstPath%\examples
-:md6
-@echo on
-
-@if /I NOT Test%1==TestDLL goto copylib
-copy %srcPath%\libusb-%version%.dll %dstPath%\dll
-copy %srcPath%\libusb-%version%.pdb %dstPath%\dll
-:copylib
-copy %srcPath%\libusb-%version%.lib %dstPath%\lib
-
-@echo off
-
-if exist examples\lsusb_ddkbuild goto md7
-md examples\lsusb_ddkbuild
-:md7
-
-cd examples\lsusb_ddkbuild
-copy ..\..\msvc\lsusb_sources sources >NUL 2>&1
-@echo on
-build -cwgZ
-@echo off
-if errorlevel 1 goto buildlsusberror
-cd ..\..
-
-set srcPath=examples\lsusb_ddkbuild\obj%BUILD_ALT_DIR%\%cpudir%
-@echo on
-
-copy %srcPath%\lsusb.exe %dstPath%\examples
-copy %srcPath%\lsusb.pdb %dstPath%\examples
-
-cd msvc
-goto done
-
-
-:builderror
-cd ..\..\msvc
-echo Build failed
-goto done
-
-:buildlsusberror
-cd ..\..\msvc
-echo lsusb build failed
-goto done
-
-:usage
-echo ddk_build must be run in a WDK build environment
-pause
-goto done
-
-:done
diff --git a/third_party/libusb/msvc/inttypes.h b/third_party/libusb/msvc/inttypes.h
deleted file mode 100644
index 289bb50..0000000
--- a/third_party/libusb/msvc/inttypes.h
+++ /dev/null
@@ -1,295 +0,0 @@
-/**
- * This file has no copyright assigned and is placed in the Public Domain.
- * This file was original part of the w64 mingw-runtime package.
- */
-
-/*
- *  THIS SOFTWARE IS NOT COPYRIGHTED
- *
- *  Modified for libusb/MSVC: Pete Batard <pbatard@gmail.com>
- *
- *  This source code is offered for use in the public domain. You may
- *  use, modify or distribute it freely.
- *
- *  This code is distributed in the hope that it will be useful but
- *  WITHOUT ANY WARRANTY. ALL WARRANTIES, EXPRESS OR IMPLIED ARE HEREBY
- *  DISCLAIMED. This includes but is not limited to warranties of
- *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
- *
- *  Date: 2010-04-02
- */
-
-#ifndef _MSC_VER
-#error This header should only be used with Microsoft compilers
-#endif
-
-/* 7.8 Format conversion of integer types <inttypes.h> */
-
-#ifndef _INTTYPES_H_
-#define _INTTYPES_H_
-
-#include <stdint.h>
-
-#ifdef	__cplusplus
-extern	"C"	{
-#endif
-
-typedef struct {
-	intmax_t quot;
-	intmax_t rem;
-	} imaxdiv_t;
-
-
-/* 7.8.1 Macros for format specifiers
- *
- * MS runtime does not yet understand C9x standard "ll"
- * length specifier. It appears to treat "ll" as "l".
- * The non-standard I64 length specifier causes warning in GCC,
- * but understood by MS runtime functions.
- */
-
-/* fprintf macros for signed types */
-#define PRId8 "d"
-#define PRId16 "d"
-#define PRId32 "d"
-#define PRId64 "I64d"
-
-#define PRIdLEAST8 "d"
-#define PRIdLEAST16 "d"
-#define PRIdLEAST32 "d"
-#define PRIdLEAST64 "I64d"
-
-#define PRIdFAST8 "d"
-#define PRIdFAST16 "d"
-#define PRIdFAST32 "d"
-#define PRIdFAST64 "I64d"
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-#define PRIdMAX "I64d"
-
-#define PRIi8 "i"
-#define PRIi16 "i"
-#define PRIi32 "i"
-#define PRIi64 "I64i"
-
-#define PRIiLEAST8 "i"
-#define PRIiLEAST16 "i"
-#define PRIiLEAST32 "i"
-#define PRIiLEAST64 "I64i"
-
-#define PRIiFAST8 "i"
-#define PRIiFAST16 "i"
-#define PRIiFAST32 "i"
-#define PRIiFAST64 "I64i"
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-#define PRIiMAX "I64i"
-
-#define PRIo8 "o"
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-#define PRIo32 "o"
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-
-#define PRIoLEAST8 "o"
-#define PRIoLEAST16 "o"
-#define PRIoLEAST32 "o"
-#define PRIoLEAST64 "I64o"
-
-#define PRIoFAST8 "o"
-#define PRIoFAST16 "o"
-#define PRIoFAST32 "o"
-#define PRIoFAST64 "I64o"
-
-#define PRIoMAX "I64o"
-
-/* fprintf macros for unsigned types */
-#define PRIu8 "u"
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-#define PRIu32 "u"
-#define PRIu64 "I64u"
-
-
-#define PRIuLEAST8 "u"
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-#define PRIuLEAST32 "u"
-#define PRIuLEAST64 "I64u"
-
-#define PRIuFAST8 "u"
-#define PRIuFAST16 "u"
-#define PRIuFAST32 "u"
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-#define PRIx8 "x"
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-#define PRIxLEAST8 "x"
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-#define PRIxFAST8 "x"
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-#define PRIxFAST32 "x"
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-
-#define PRIxMAX "I64x"
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-#define PRIX8 "X"
-#define PRIX16 "X"
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-
-#define PRIXLEAST8 "X"
-#define PRIXLEAST16 "X"
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-#define PRIXLEAST64 "I64X"
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-#define PRIXMAX "I64X"
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-/*
- *   fscanf macros for signed int types
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- */
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-#define SCNd16 "hd"
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-#define SCNdLEAST16 "hd"
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-#define SCNdFAST16 "hd"
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-#define SCNdMAX "I64d"
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-#define SCNi64 "I64i"
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-#define SCNiLEAST16 "hi"
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-#define SCNiFAST16 "hi"
-#define SCNiFAST32 "i"
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-
-#define SCNiMAX "I64i"
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-#define SCNo16 "ho"
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-#define SCNoLEAST16 "ho"
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-#define SCNoLEAST64 "I64o"
-
-#define SCNoFAST16 "ho"
-#define SCNoFAST32 "o"
-#define SCNoFAST64 "I64o"
-
-#define SCNoMAX "I64o"
-
-#define SCNx16 "hx"
-#define SCNx32 "x"
-#define SCNx64 "I64x"
-
-#define SCNxLEAST16 "hx"
-#define SCNxLEAST32 "x"
-#define SCNxLEAST64 "I64x"
-
-#define SCNxFAST16 "hx"
-#define SCNxFAST32 "x"
-#define SCNxFAST64 "I64x"
-
-#define SCNxMAX "I64x"
-
-/* fscanf macros for unsigned int types */
-
-#define SCNu16 "hu"
-#define SCNu32 "u"
-#define SCNu64 "I64u"
-
-#define SCNuLEAST16 "hu"
-#define SCNuLEAST32 "u"
-#define SCNuLEAST64 "I64u"
-
-#define SCNuFAST16 "hu"
-#define SCNuFAST32 "u"
-#define SCNuFAST64 "I64u"
-
-#define SCNuMAX "I64u"
-
-#ifdef _WIN64
-#define PRIdPTR "I64d"
-#define PRIiPTR "I64i"
-#define PRIoPTR "I64o"
-#define PRIuPTR "I64u"
-#define PRIxPTR "I64x"
-#define PRIXPTR "I64X"
-#define SCNdPTR "I64d"
-#define SCNiPTR "I64i"
-#define SCNoPTR "I64o"
-#define SCNxPTR "I64x"
-#define SCNuPTR "I64u"
-#else
-#define PRIdPTR "d"
-#define PRIiPTR "i"
-#define PRIoPTR "o"
-#define PRIuPTR "u"
-#define PRIxPTR "x"
-#define PRIXPTR "X"
-#define SCNdPTR "d"
-#define SCNiPTR "i"
-#define SCNoPTR "o"
-#define SCNxPTR "x"
- #define SCNuPTR "u"
-#endif
-
-#if defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
-/*
- * no length modifier for char types prior to C9x
- * MS runtime  scanf appears to treat "hh" as "h"
- */
-
-/* signed char */
-#define SCNd8 "hhd"
-#define SCNdLEAST8 "hhd"
-#define SCNdFAST8 "hhd"
-
-#define SCNi8 "hhi"
-#define SCNiLEAST8 "hhi"
-#define SCNiFAST8 "hhi"
-
-#define SCNo8 "hho"
-#define SCNoLEAST8 "hho"
-#define SCNoFAST8 "hho"
-
-#define SCNx8 "hhx"
-#define SCNxLEAST8 "hhx"
-#define SCNxFAST8 "hhx"
-
-/* unsigned char */
-#define SCNu8 "hhu"
-#define SCNuLEAST8 "hhu"
-#define SCNuFAST8 "hhu"
-#endif /* __STDC_VERSION__ >= 199901 */
-
-
-#ifdef	__cplusplus
-}
-#endif
-
-#endif /* ndef _INTTYPES_H */
diff --git a/third_party/libusb/msvc/libusb.dsw b/third_party/libusb/msvc/libusb.dsw
deleted file mode 100644
index e4de346..0000000
--- a/third_party/libusb/msvc/libusb.dsw
+++ /dev/null
@@ -1,56 +0,0 @@
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-{{{
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diff --git a/third_party/libusb/msvc/libusb_dll.dsp b/third_party/libusb/msvc/libusb_dll.dsp
deleted file mode 100644
index 4754a531..0000000
--- a/third_party/libusb/msvc/libusb_dll.dsp
+++ /dev/null
@@ -1,190 +0,0 @@
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diff --git a/third_party/libusb/msvc/libusb_sources b/third_party/libusb/msvc/libusb_sources
deleted file mode 100644
index 8e8e65c..0000000
--- a/third_party/libusb/msvc/libusb_sources
+++ /dev/null
@@ -1,36 +0,0 @@
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-INCLUDES=..;..\..\msvc;$(DDK_INC_PATH)
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-
-# http://jpassing.com/2009/10/21/ltcg-issues-with-the-win7amd64-environment-of-wdk-7600/
-# prevents the following error when using the 64 bit static lib with Visual Studio 2010:
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-# (compiler file 'f:\dd\vctools\compiler\utc\src\p2\p2symtab.c', line 1823)"
-# and the following with Visual Studio 2010:
-# "fatal error C1047: The object or library file 'libusb-1.0.lib' was created with
-#  an older compiler than other objects; rebuild old objects and libraries"
-USER_C_FLAGS=/GL-
-
-TARGETLIBS=$(SDK_LIB_PATH)\kernel32.lib
-
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-	..\io.c \
-	..\sync.c \
-	threads_windows.c \
-	poll_windows.c \
-	windows_usb.c \
-	..\libusb-1.0.rc
diff --git a/third_party/libusb/msvc/libusb_static.dsp b/third_party/libusb/msvc/libusb_static.dsp
deleted file mode 100644
index f866a63..0000000
--- a/third_party/libusb/msvc/libusb_static.dsp
+++ /dev/null
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-SOURCE=..\libusb\os\poll_windows.h
-# End Source File
-# Begin Source File
-
-SOURCE=..\libusb\os\threads_posix.h
-# End Source File
-# Begin Source File
-
-SOURCE=..\libusb\os\threads_windows.h
-# End Source File
-# Begin Source File
-
-SOURCE=..\libusb\os\windows_usb.h
-# End Source File
-# End Group
-# End Target
-# End Project
diff --git a/third_party/libusb/msvc/lsusb_sources b/third_party/libusb/msvc/lsusb_sources
deleted file mode 100644
index dbfefbb..0000000
--- a/third_party/libusb/msvc/lsusb_sources
+++ /dev/null
@@ -1,19 +0,0 @@
-TARGETNAME=lsusb
-TARGETTYPE=PROGRAM
-386_STDCALL=0
-
-_NT_TARGET_VERSION= $(_NT_TARGET_VERSION_WINXP)
-!IFNDEF MSC_WARNING_LEVEL
-MSC_WARNING_LEVEL=/W3
-!ENDIF
-
-!IFDEF STATIC_LIBC
-USE_LIBCMT=1
-!ELSE
-USE_MSVCRT=1
-!ENDIF
-
-UMTYPE=console
-INCLUDES=..\..\libusb;$(DDK_INC_PATH)
-UMLIBS=..\..\libusb\os\obj$(BUILD_ALT_DIR)\*\libusb-1.0.lib
-SOURCES=..\lsusb.c
diff --git a/third_party/libusb/msvc/stdint.h b/third_party/libusb/msvc/stdint.h
deleted file mode 100644
index 00988d9..0000000
--- a/third_party/libusb/msvc/stdint.h
+++ /dev/null
@@ -1,256 +0,0 @@
-/**
- * This file has no copyright assigned and is placed in the Public Domain.
- * This file was originally part of the w64 mingw-runtime package.
- */
-
-/* ISO C9x  7.18  Integer types <stdint.h>
- * Based on ISO/IEC SC22/WG14 9899 Committee draft (SC22 N2794)
- *
- *  THIS SOFTWARE IS NOT COPYRIGHTED
- *
- *  Contributor: Danny Smith <danny_r_smith_2001@yahoo.co.nz>
- *  Modified for libusb/MSVC: Pete Batard <pbatard@gmail.com>
- *
- *  This source code is offered for use in the public domain. You may
- *  use, modify or distribute it freely.
- *
- *  This code is distributed in the hope that it will be useful but
- *  WITHOUT ANY WARRANTY. ALL WARRANTIES, EXPRESS OR IMPLIED ARE HEREBY
- *  DISCLAIMED. This includes but is not limited to warranties of
- *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
- *
- *  Date: 2010-04-02
- */
-
-#ifndef _MSC_VER
-#error This header should only be used with Microsoft compilers
-#endif
-
-#ifndef _STDINT_H
-#define _STDINT_H
-
-#ifndef _INTPTR_T_DEFINED
-#define _INTPTR_T_DEFINED
-#ifndef __intptr_t_defined
-#define __intptr_t_defined
-#undef intptr_t
-#ifdef _WIN64
-  typedef __int64 intptr_t;
-#else
-  typedef int intptr_t;
-#endif /* _WIN64 */
-#endif /* __intptr_t_defined */
-#endif /* _INTPTR_T_DEFINED */
-
-#ifndef _UINTPTR_T_DEFINED
-#define _UINTPTR_T_DEFINED
-#ifndef __uintptr_t_defined
-#define __uintptr_t_defined
-#undef uintptr_t
-#ifdef _WIN64
-  typedef unsigned __int64 uintptr_t;
-#else
-  typedef unsigned int uintptr_t;
-#endif /* _WIN64 */
-#endif /* __uintptr_t_defined */
-#endif /* _UINTPTR_T_DEFINED */
-
-#ifndef _PTRDIFF_T_DEFINED
-#define _PTRDIFF_T_DEFINED
-#ifndef _PTRDIFF_T_
-#define _PTRDIFF_T_
-#undef ptrdiff_t
-#ifdef _WIN64
-  typedef __int64 ptrdiff_t;
-#else
-  typedef int ptrdiff_t;
-#endif /* _WIN64 */
-#endif /* _PTRDIFF_T_ */
-#endif /* _PTRDIFF_T_DEFINED */
-
-#ifndef _WCHAR_T_DEFINED
-#define _WCHAR_T_DEFINED
-#ifndef __cplusplus
-  typedef unsigned short wchar_t;
-#endif /* C++ */
-#endif /* _WCHAR_T_DEFINED */
-
-#ifndef _WCTYPE_T_DEFINED
-#define _WCTYPE_T_DEFINED
-#ifndef _WINT_T
-#define _WINT_T
-  typedef unsigned short wint_t;
-  typedef unsigned short wctype_t;
-#endif /* _WINT_T */
-#endif /* _WCTYPE_T_DEFINED */
-
-/* 7.18.1.1  Exact-width integer types */
-typedef __int8 int8_t;
-typedef unsigned __int8   uint8_t;
-typedef __int16  int16_t;
-typedef unsigned __int16  uint16_t;
-typedef __int32  int32_t;
-typedef unsigned __int32  uint32_t;
-typedef __int64  int64_t;
-typedef unsigned __int64   uint64_t;
-
-/* 7.18.1.2  Minimum-width integer types */
-typedef signed char int_least8_t;
-typedef unsigned char   uint_least8_t;
-typedef short  int_least16_t;
-typedef unsigned short  uint_least16_t;
-typedef int  int_least32_t;
-typedef unsigned   uint_least32_t;
-typedef __int64  int_least64_t;
-typedef unsigned __int64   uint_least64_t;
-
-/*  7.18.1.3  Fastest minimum-width integer types
- *  Not actually guaranteed to be fastest for all purposes
- *  Here we use the exact-width types for 8 and 16-bit ints.
- */
-typedef __int8 int_fast8_t;
-typedef unsigned __int8 uint_fast8_t;
-typedef __int16  int_fast16_t;
-typedef unsigned __int16  uint_fast16_t;
-typedef __int32  int_fast32_t;
-typedef unsigned  __int32  uint_fast32_t;
-typedef __int64  int_fast64_t;
-typedef unsigned __int64   uint_fast64_t;
-
-/* 7.18.1.5  Greatest-width integer types */
-typedef __int64  intmax_t;
-typedef unsigned __int64   uintmax_t;
-
-/* 7.18.2  Limits of specified-width integer types */
-
-/* 7.18.2.1  Limits of exact-width integer types */
-#define INT8_MIN (-128)
-#define INT16_MIN (-32768)
-#define INT32_MIN (-2147483647 - 1)
-#define INT64_MIN  (-9223372036854775807LL - 1)
-
-#define INT8_MAX 127
-#define INT16_MAX 32767
-#define INT32_MAX 2147483647
-#define INT64_MAX 9223372036854775807LL
-
-#define UINT8_MAX 255
-#define UINT16_MAX 65535
-#define UINT32_MAX 0xffffffffU  /* 4294967295U */
-#define UINT64_MAX 0xffffffffffffffffULL /* 18446744073709551615ULL */
-
-/* 7.18.2.2  Limits of minimum-width integer types */
-#define INT_LEAST8_MIN INT8_MIN
-#define INT_LEAST16_MIN INT16_MIN
-#define INT_LEAST32_MIN INT32_MIN
-#define INT_LEAST64_MIN INT64_MIN
-
-#define INT_LEAST8_MAX INT8_MAX
-#define INT_LEAST16_MAX INT16_MAX
-#define INT_LEAST32_MAX INT32_MAX
-#define INT_LEAST64_MAX INT64_MAX
-
-#define UINT_LEAST8_MAX UINT8_MAX
-#define UINT_LEAST16_MAX UINT16_MAX
-#define UINT_LEAST32_MAX UINT32_MAX
-#define UINT_LEAST64_MAX UINT64_MAX
-
-/* 7.18.2.3  Limits of fastest minimum-width integer types */
-#define INT_FAST8_MIN INT8_MIN
-#define INT_FAST16_MIN INT16_MIN
-#define INT_FAST32_MIN INT32_MIN
-#define INT_FAST64_MIN INT64_MIN
-
-#define INT_FAST8_MAX INT8_MAX
-#define INT_FAST16_MAX INT16_MAX
-#define INT_FAST32_MAX INT32_MAX
-#define INT_FAST64_MAX INT64_MAX
-
-#define UINT_FAST8_MAX UINT8_MAX
-#define UINT_FAST16_MAX UINT16_MAX
-#define UINT_FAST32_MAX UINT32_MAX
-#define UINT_FAST64_MAX UINT64_MAX
-
-/* 7.18.2.4  Limits of integer types capable of holding
-    object pointers */
-#ifdef _WIN64
-#define INTPTR_MIN INT64_MIN
-#define INTPTR_MAX INT64_MAX
-#define UINTPTR_MAX UINT64_MAX
-#else
-#define INTPTR_MIN INT32_MIN
-#define INTPTR_MAX INT32_MAX
-#define UINTPTR_MAX UINT32_MAX
-#endif
-
-/* 7.18.2.5  Limits of greatest-width integer types */
-#define INTMAX_MIN INT64_MIN
-#define INTMAX_MAX INT64_MAX
-#define UINTMAX_MAX UINT64_MAX
-
-/* 7.18.3  Limits of other integer types */
-#ifdef _WIN64
-#define PTRDIFF_MIN INT64_MIN
-#define PTRDIFF_MAX INT64_MAX
-#else
-#define PTRDIFF_MIN INT32_MIN
-#define PTRDIFF_MAX INT32_MAX
-#endif
-
-#define SIG_ATOMIC_MIN INT32_MIN
-#define SIG_ATOMIC_MAX INT32_MAX
-
-#ifndef SIZE_MAX
-#ifdef _WIN64
-#define SIZE_MAX UINT64_MAX
-#else
-#define SIZE_MAX UINT32_MAX
-#endif
-#endif
-
-#ifndef WCHAR_MIN  /* also in wchar.h */
-#define WCHAR_MIN 0U
-#define WCHAR_MAX 0xffffU
-#endif
-
-/*
- * wint_t is unsigned short for compatibility with MS runtime
- */
-#define WINT_MIN 0U
-#define WINT_MAX 0xffffU
-
-
-/* 7.18.4  Macros for integer constants */
-
-/* 7.18.4.1  Macros for minimum-width integer constants
-
-    Accoding to Douglas Gwyn <gwyn@arl.mil>:
-	"This spec was changed in ISO/IEC 9899:1999 TC1; in ISO/IEC
-	9899:1999 as initially published, the expansion was required
-	to be an integer constant of precisely matching type, which
-	is impossible to accomplish for the shorter types on most
-	platforms, because C99 provides no standard way to designate
-	an integer constant with width less than that of type int.
-	TC1 changed this to require just an integer constant
-	*expression* with *promoted* type."
-
-	The trick used here is from Clive D W Feather.
-*/
-
-#define INT8_C(val) (INT_LEAST8_MAX-INT_LEAST8_MAX+(val))
-#define INT16_C(val) (INT_LEAST16_MAX-INT_LEAST16_MAX+(val))
-#define INT32_C(val) (INT_LEAST32_MAX-INT_LEAST32_MAX+(val))
-/*  The 'trick' doesn't work in C89 for long long because, without
-    suffix, (val) will be evaluated as int, not intmax_t */
-#define INT64_C(val) val##i64
-
-#define UINT8_C(val) (val)
-#define UINT16_C(val) (val)
-#define UINT32_C(val) (val##i32)
-#define UINT64_C(val) val##ui64
-
-/* 7.18.4.2  Macros for greatest-width integer constants */
-#define INTMAX_C(val) val##i64
-#define UINTMAX_C(val) val##ui64
-
-#endif