Non-SFI Mode: Build ipc/ library by PNaCl toolchain for nacl_helper_nonsfi.

This CL is to build ipc/ for nacl_helper_nonsfi.
The library is similar to ipc_nacl, but slightly different:
- The IPC::Channel should use ChannelPosix rather than ChannelNaCl,
  as it runs under linux directly.
- Some features of ChannelPosix cannot be compiled by PNaCl toolchain for
  Non-SFI build, but these are not necessary for nacl_helper_nonsfi.
  These are dropped by "ifdef" guard.
Note that this library is not used yet, but should be built successfully.

BUG=358465
TEST=Ran trybot. Implement nacl_helper_nonsfi on top of this CL, and made sure it works.

Review URL: https://codereview.chromium.org/659243002

Cr-Commit-Position: refs/heads/master@{#301037}

7 files changed, 98 insertions, 13 deletions

diff --git a/components/nacl_nonsfi.gyp b/components/nacl_nonsfi.gyp
index 5b96c7e..1625451 100644
--- a/components/nacl_nonsfi.gyp
+++ b/components/nacl_nonsfi.gyp
@@ -13,6 +13,20 @@
     ['disable_nacl==0 and disable_nacl_untrusted==0', {
       'targets': [
         {
+          # nacl_helper_nonsfi is similar to nacl_helper (built in nacl.gyp)
+          # but for the NaCl plugin in Non-SFI mode.
+          # This binary is built using the PNaCl toolchain, but it is native
+          # linux binary and will run on Linux directly.
+          # Most library code can be shared with the one for untrusted build
+          # (i.e. the one for irt.nexe built by the NaCl/PNaCl toolchain), but
+          # as nacl_helper_nonsfi runs on Linux, there are some differences,
+          # such as MessageLoopForIO (which is based on libevent in Non-SFI
+          # mode) or ipc_channel implementation.
+          # Because of the toolchain, in both builds, OS_NACL macro (derived
+          # from __native_client__ macro) is defined. Code can test whether
+          # __native_client_nonsfi__ is #defined in order to determine
+          # whether it is being compiled for SFI mode or Non-SFI mode.
+          #
           # Currently, nacl_helper_nonsfi is under development and the binary
           # does nothing (i.e. it has only empty main(), now).
           # TODO(crbug.com/358465): Implement it then switch nacl_helper in
@@ -48,6 +62,7 @@
                   '>(tc_lib_dir_nonsfi_helper32)/libgles2_implementation_nacl.a',
                   '>(tc_lib_dir_nonsfi_helper32)/libgles2_utils_nacl.a',
                   '>(tc_lib_dir_nonsfi_helper32)/libgpu_ipc_nacl.a',
+                  '>(tc_lib_dir_nonsfi_helper32)/libipc_nacl_nonsfi.a',
                   '>(tc_lib_dir_nonsfi_helper32)/libshared_memory_support_nacl.a',
                 ],
               }],
@@ -55,6 +70,7 @@
           },
           'dependencies': [
             '../base/base_nacl.gyp:base_nacl_nonsfi',
+            '../ipc/ipc_nacl.gyp:ipc_nacl_nonsfi',
             '../native_client/src/nonsfi/irt/irt.gyp:nacl_sys_private',
             '../native_client/src/untrusted/nacl/nacl.gyp:nacl_lib_newlib',
             '../native_client/tools.gyp:prep_toolchain',
diff --git a/ipc/ipc_channel.cc b/ipc/ipc_channel.cc
index a6ee14c..4a4e40d 100644
--- a/ipc/ipc_channel.cc
+++ b/ipc/ipc_channel.cc
@@ -10,14 +10,12 @@
 #include "base/rand_util.h"
 #include "base/strings/stringprintf.h"
 
-#if !defined(OS_NACL)
 namespace {
 
 // Global atomic used to guarantee channel IDs are unique.
 base::StaticAtomicSequenceNumber g_last_id;
 
 }  // namespace
-#endif
 
 namespace IPC {
 
@@ -39,4 +37,3 @@ std::string Channel::GenerateUniqueRandomChannelID() {
 }
 
 }  // namespace IPC
-
diff --git a/ipc/ipc_channel.h b/ipc/ipc_channel.h
index 2d8d449..3ed5e6a 100644
--- a/ipc/ipc_channel.h
+++ b/ipc/ipc_channel.h
@@ -179,7 +179,11 @@ class IPC_EXPORT Channel : public Sender {
   // deleted once the contents of the Message have been sent.
   virtual bool Send(Message* message) = 0;
 
-#if defined(OS_POSIX) && !defined(OS_NACL)
+  // NaCl in Non-SFI mode runs on Linux directly, and the following functions
+  // compiled on Linux are also needed. Please see also comments in
+  // components/nacl_nonsfi.gyp for more details.
+#if defined(OS_POSIX) && \
+    (!defined(OS_NACL) || defined(__native_client_nonsfi__))
   // On POSIX an IPC::Channel wraps a socketpair(), this method returns the
   // FD # for the client end of the socket.
   // This method may only be called on the server side of a channel.
@@ -190,13 +194,13 @@ class IPC_EXPORT Channel : public Sender {
   // file descriptor to the caller.
   // This method can be called on any thread.
   virtual base::ScopedFD TakeClientFileDescriptor() = 0;
-#endif  // defined(OS_POSIX) && !defined(OS_NACL)
+#endif
 
   // Returns true if a named server channel is initialized on the given channel
   // ID. Even if true, the server may have already accepted a connection.
   static bool IsNamedServerInitialized(const std::string& channel_id);
 
-#if !defined(OS_NACL)
+#if !defined(OS_NACL) || defined(__native_client_nonsfi__)
   // Generates a channel ID that's non-predictable and unique.
   static std::string GenerateUniqueRandomChannelID();
 
diff --git a/ipc/ipc_channel_posix.cc b/ipc/ipc_channel_posix.cc
index c864db2..8e74c3a 100644
--- a/ipc/ipc_channel_posix.cc
+++ b/ipc/ipc_channel_posix.cc
@@ -10,13 +10,16 @@
 #include <sys/socket.h>
 #include <sys/stat.h>
 #include <sys/types.h>
-#include <sys/un.h>
 #include <unistd.h>
 
 #if defined(OS_OPENBSD)
 #include <sys/uio.h>
 #endif
 
+#if !defined(__native_client_nonsfi__)
+#include <sys/un.h>
+#endif
+
 #include <map>
 #include <string>
 
@@ -255,6 +258,10 @@ bool ChannelPosix::CreatePipe(
     }
 #endif   // IPC_USES_READWRITE
   } else if (mode_ & MODE_NAMED_FLAG) {
+#if defined(__native_client_nonsfi__)
+    LOG(FATAL)
+        << "IPC channels in nacl_helper_nonsfi should not be in NAMED mode.";
+#else
     // Case 2 from comment above.
     int local_pipe_fd = -1;
 
@@ -276,6 +283,7 @@ bool ChannelPosix::CreatePipe(
     }
 
     local_pipe.reset(local_pipe_fd);
+#endif  // !defined(__native_client_nonsfi__)
   } else {
     local_pipe.reset(PipeMap::GetInstance()->Lookup(pipe_name_));
     if (mode_ & MODE_CLIENT_FLAG) {
@@ -336,10 +344,16 @@ bool ChannelPosix::CreatePipe(
   }
 #endif  // IPC_USES_READWRITE
 
-  if ((mode_ & MODE_SERVER_FLAG) && (mode_ & MODE_NAMED_FLAG))
+  if ((mode_ & MODE_SERVER_FLAG) && (mode_ & MODE_NAMED_FLAG)) {
+#if defined(__native_client_nonsfi__)
+    LOG(FATAL) << "IPC channels in nacl_helper_nonsfi "
+               << "should not be in NAMED or SERVER mode.";
+#else
     server_listen_pipe_.reset(local_pipe.release());
-  else
+#endif
+  } else {
     pipe_.reset(local_pipe.release());
+  }
   return true;
 }
 
@@ -351,6 +365,10 @@ bool ChannelPosix::Connect() {
 
   bool did_connect = true;
   if (server_listen_pipe_.is_valid()) {
+#if defined(__native_client_nonsfi__)
+    LOG(FATAL) << "IPC channels in nacl_helper_nonsfi "
+               << "should always be in client mode.";
+#else
     // Watch the pipe for connections, and turn any connections into
     // active sockets.
     base::MessageLoopForIO::current()->WatchFileDescriptor(
@@ -359,6 +377,7 @@ bool ChannelPosix::Connect() {
         base::MessageLoopForIO::WATCH_READ,
         &server_listen_connection_watcher_,
         this);
+#endif
   } else {
     did_connect = AcceptConnection();
   }
@@ -581,10 +600,13 @@ bool ChannelPosix::HasAcceptedConnection() const {
   return AcceptsConnections() && pipe_.is_valid();
 }
 
+#if !defined(__native_client_nonsfi__)
+// GetPeerEuid is not supported in nacl_helper_nonsfi.
 bool ChannelPosix::GetPeerEuid(uid_t* peer_euid) const {
   DCHECK(!(mode_ & MODE_SERVER) || HasAcceptedConnection());
   return IPC::GetPeerEuid(pipe_.get(), peer_euid);
 }
+#endif
 
 void ChannelPosix::ResetToAcceptingConnectionState() {
   // Unregister libevent for the unix domain socket and close it.
@@ -633,6 +655,10 @@ void ChannelPosix::SetGlobalPid(int pid) {
 // Called by libevent when we can read from the pipe without blocking.
 void ChannelPosix::OnFileCanReadWithoutBlocking(int fd) {
   if (fd == server_listen_pipe_.get()) {
+#if defined(__native_client_nonsfi__)
+    LOG(FATAL)
+        << "IPC channels in nacl_helper_nonsfi should not be SERVER mode.";
+#else
     int new_pipe = 0;
     if (!ServerAcceptConnection(server_listen_pipe_.get(), &new_pipe) ||
         new_pipe < 0) {
@@ -671,6 +697,7 @@ void ChannelPosix::OnFileCanReadWithoutBlocking(int fd) {
       NOTREACHED() << "AcceptConnection should not fail on server";
     }
     waiting_connect_ = false;
+#endif
   } else if (fd == pipe_) {
     if (waiting_connect_ && (mode_ & MODE_SERVER_FLAG)) {
       waiting_connect_ = false;
@@ -923,11 +950,15 @@ bool ChannelPosix::ExtractFileDescriptorsFromMsghdr(msghdr* msg) {
                         file_descriptors,
                         file_descriptors + num_file_descriptors);
 
+#if !defined(__native_client_nonsfi__)
+      // The PNaCl toolchain for Non-SFI binary build does not support
+      // MSG_CTRUNC.
       // Check this after adding the FDs so we don't leak them.
       if (msg->msg_flags & MSG_CTRUNC) {
         ClearInputFDs();
         return false;
       }
+#endif
 
       return true;
     }
@@ -1032,9 +1063,14 @@ void ChannelPosix::Close() {
   }
 
   if (server_listen_pipe_.is_valid()) {
+#if defined(__native_client_nonsfi__)
+    LOG(FATAL)
+        << "IPC channels in nacl_helper_nonsfi should not be SERVER mode.";
+#else
     server_listen_pipe_.reset();
     // Unregister libevent for the listening socket and close it.
     server_listen_connection_watcher_.StopWatchingFileDescriptor();
+#endif
   }
 
   CloseClientFileDescriptor();
diff --git a/ipc/ipc_channel_proxy.cc b/ipc/ipc_channel_proxy.cc
index e2d7ad4..07f9552 100644
--- a/ipc/ipc_channel_proxy.cc
+++ b/ipc/ipc_channel_proxy.cc
@@ -434,7 +434,8 @@ void ChannelProxy::ClearIPCTaskRunner() {
   context()->ClearIPCTaskRunner();
 }
 
-#if defined(OS_POSIX) && !defined(OS_NACL)
+#if defined(OS_POSIX) && \
+    (!defined(OS_NACL) || defined(__native_client_nonsfi__))
 // See the TODO regarding lazy initialization of the channel in
 // ChannelProxy::Init().
 int ChannelProxy::GetClientFileDescriptor() {
diff --git a/ipc/ipc_channel_proxy.h b/ipc/ipc_channel_proxy.h
index 71a014b..e2ad4a9 100644
--- a/ipc/ipc_channel_proxy.h
+++ b/ipc/ipc_channel_proxy.h
@@ -119,11 +119,12 @@ class IPC_EXPORT ChannelProxy : public Sender, public base::NonThreadSafe {
   // Returns base::kNullProcessId if the peer is not connected yet.
   base::ProcessId GetPeerPID() const { return context_->peer_pid_; }
 
-#if defined(OS_POSIX) && !defined(OS_NACL)
+#if defined(OS_POSIX) && \
+    (!defined(OS_NACL) || defined(__native_client_nonsfi__))
   // Calls through to the underlying channel's methods.
   int GetClientFileDescriptor();
   base::ScopedFD TakeClientFileDescriptor();
-#endif  // defined(OS_POSIX)
+#endif
 
  protected:
   class Context;
diff --git a/ipc/ipc_nacl.gyp b/ipc/ipc_nacl.gyp
index 3119f46..6f0d522 100644
--- a/ipc/ipc_nacl.gyp
+++ b/ipc/ipc_nacl.gyp
@@ -25,8 +25,38 @@
             'build_irt': 1,
           },
           'dependencies': [
-            '<(DEPTH)/native_client/tools.gyp:prep_toolchain',
             '../base/base_nacl.gyp:base_nacl',
+            '../native_client/tools.gyp:prep_toolchain',
+          ],
+        },
+        {
+          'target_name': 'ipc_nacl_nonsfi',
+          'type': 'none',
+          'variables': {
+            'ipc_target': 1,
+            'nacl_untrusted_build': 1,
+            'nlib_target': 'libipc_nacl_nonsfi.a',
+            'build_glibc': 0,
+            'build_newlib': 0,
+            'build_irt': 0,
+            'build_pnacl_newlib': 0,
+            'build_nonsfi_helper': 1,
+
+            # Use linux IPC channel implementation for nacl_helper_nonsfi,
+            # instead of NaCl's IPC implementation (ipc_channel_nacl.cc),
+            # because nacl_helper_nonsfi will be running directly on Linux.
+            # ipc_channel_nacl.cc is excluded below.
+            'sources': [
+              'ipc_channel.cc',
+              'ipc_channel_posix.cc',
+            ],
+          },
+          'sources!': [
+            'ipc_channel_nacl.cc',
+          ],
+          'dependencies': [
+            '../base/base_nacl.gyp:base_nacl_nonsfi',
+            '../native_client/tools.gyp:prep_toolchain',
           ],
         },
       ],