Move debug-related stuff from base to the base/debug directory and use the

base::debug namespace.

This splits apart debug_util into base/debugger and base/stack_trace
There are still two functions in debug_util that I'm not sure what to do with.
Since this uses the base::debug namespace, I removed the functions in
debugger.h from the static class and just made them free functions in the
namespace.

TEST=it compiles
BUG=none
Review URL: http://codereview.chromium.org/3945002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@63859 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 165 insertions, 0 deletions

diff --git a/base/debug/debugger_posix.cc b/base/debug/debugger_posix.cc
new file mode 100644
index 0000000..a5ab066
--- /dev/null
+++ b/base/debug/debugger_posix.cc
@@ -0,0 +1,165 @@
+// Copyright (c) 2010 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.
+
+#include "base/debug/debugger.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <sys/sysctl.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <string>
+#include <vector>
+
+#if defined(__GLIBCXX__)
+#include <cxxabi.h>
+#endif
+
+#if defined(OS_MACOSX)
+#include <AvailabilityMacros.h>
+#endif
+
+#include <iostream>
+
+#include "base/basictypes.h"
+#include "base/compat_execinfo.h"
+#include "base/eintr_wrapper.h"
+#include "base/logging.h"
+#include "base/safe_strerror_posix.h"
+#include "base/scoped_ptr.h"
+#include "base/string_piece.h"
+#include "base/stringprintf.h"
+
+#if defined(USE_SYMBOLIZE)
+#include "base/third_party/symbolize/symbolize.h"
+#endif
+
+namespace base {
+namespace debug {
+
+bool SpawnDebuggerOnProcess(unsigned /* process_id */) {
+  NOTIMPLEMENTED();
+  return false;
+}
+
+#if defined(OS_MACOSX)
+
+// Based on Apple's recommended method as described in
+// http://developer.apple.com/qa/qa2004/qa1361.html
+bool BeingDebugged() {
+  // If the process is sandboxed then we can't use the sysctl, so cache the
+  // value.
+  static bool is_set = false;
+  static bool being_debugged = false;
+
+  if (is_set) {
+    return being_debugged;
+  }
+
+  // Initialize mib, which tells sysctl what info we want.  In this case,
+  // we're looking for information about a specific process ID.
+  int mib[] = {
+    CTL_KERN,
+    KERN_PROC,
+    KERN_PROC_PID,
+    getpid()
+  };
+
+  // Caution: struct kinfo_proc is marked __APPLE_API_UNSTABLE.  The source and
+  // binary interfaces may change.
+  struct kinfo_proc info;
+  size_t info_size = sizeof(info);
+
+  int sysctl_result = sysctl(mib, arraysize(mib), &info, &info_size, NULL, 0);
+  DCHECK_EQ(sysctl_result, 0);
+  if (sysctl_result != 0) {
+    is_set = true;
+    being_debugged = false;
+    return being_debugged;
+  }
+
+  // This process is being debugged if the P_TRACED flag is set.
+  is_set = true;
+  being_debugged = (info.kp_proc.p_flag & P_TRACED) != 0;
+  return being_debugged;
+}
+
+#elif defined(OS_LINUX)
+
+// We can look in /proc/self/status for TracerPid.  We are likely used in crash
+// handling, so we are careful not to use the heap or have side effects.
+// Another option that is common is to try to ptrace yourself, but then we
+// can't detach without forking(), and that's not so great.
+// static
+bool BeingDebugged() {
+  int status_fd = open("/proc/self/status", O_RDONLY);
+  if (status_fd == -1)
+    return false;
+
+  // We assume our line will be in the first 1024 characters and that we can
+  // read this much all at once.  In practice this will generally be true.
+  // This simplifies and speeds up things considerably.
+  char buf[1024];
+
+  ssize_t num_read = HANDLE_EINTR(read(status_fd, buf, sizeof(buf)));
+  if (HANDLE_EINTR(close(status_fd)) < 0)
+    return false;
+
+  if (num_read <= 0)
+    return false;
+
+  StringPiece status(buf, num_read);
+  StringPiece tracer("TracerPid:\t");
+
+  StringPiece::size_type pid_index = status.find(tracer);
+  if (pid_index == StringPiece::npos)
+    return false;
+
+  // Our pid is 0 without a debugger, assume this for any pid starting with 0.
+  pid_index += tracer.size();
+  return pid_index < status.size() && status[pid_index] != '0';
+}
+
+#elif defined(OS_FREEBSD)
+
+bool DebugUtil::BeingDebugged() {
+  // TODO(benl): can we determine this under FreeBSD?
+  NOTIMPLEMENTED();
+  return false;
+}
+
+#endif  // defined(OS_FREEBSD)
+
+// We want to break into the debugger in Debug mode, and cause a crash dump in
+// Release mode. Breakpad behaves as follows:
+//
+// +-------+-----------------+-----------------+
+// | OS    | Dump on SIGTRAP | Dump on SIGABRT |
+// +-------+-----------------+-----------------+
+// | Linux |       N         |        Y        |
+// | Mac   |       Y         |        N        |
+// +-------+-----------------+-----------------+
+//
+// Thus we do the following:
+// Linux: Debug mode, send SIGTRAP; Release mode, send SIGABRT.
+// Mac: Always send SIGTRAP.
+
+#if defined(NDEBUG) && !defined(OS_MACOSX)
+#define DEBUG_BREAK() abort()
+#elif defined(ARCH_CPU_ARM_FAMILY)
+#define DEBUG_BREAK() asm("bkpt 0")
+#else
+#define DEBUG_BREAK() asm("int3")
+#endif
+
+void BreakDebugger() {
+  DEBUG_BREAK();
+}
+
+}  // namespace debug
+}  // namespace base