mac/linux: rework plugin channel file descriptor creation

chrome/plugin/plugin_channel.cc

 // Copyright (c) 2006-2008 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 "chrome/plugin/plugin_channel.h"
 
 #include "base/command_line.h"
 #include "base/process_util.h"
 #include "base/string_util.h"
 #include "build/build_config.h"
 #include "chrome/common/child_process.h"
 #include "chrome/common/plugin_messages.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/plugin/plugin_thread.h"
 
 #if defined(OS_POSIX)
 #include "chrome/common/ipc_channel_posix.h"
 #endif
 
 PluginChannel* PluginChannel::GetPluginChannel(
-    int process_id, MessageLoop* ipc_message_loop, int channel_fd) {
+    int process_id, MessageLoop* ipc_message_loop) {
   // map renderer's process id to a (single) channel to that process
   std::string channel_name = StringPrintf(
       "%d.r%d", base::GetCurrentProcId(), process_id);
 
-#if defined(OS_POSIX)
-  // If we were provided an already-open channel, associate it with
-  // the channel name in this process's name<->socket map.
-  if (channel_fd > 0)
-    IPC::AddChannelSocket(channel_name, channel_fd);
-#endif
-
   return static_cast<PluginChannel*>(PluginChannelBase::GetChannel(
       channel_name,
       IPC::Channel::MODE_SERVER,
       ClassFactory,
       ipc_message_loop,
       false));
 }
 
-PluginChannel::PluginChannel() : renderer_handle_(0), in_send_(0),
-                                 off_the_record_(false) {
+PluginChannel::PluginChannel()
+    : renderer_handle_(0),
+#if defined(OS_POSIX)
+      renderer_fd_(-1),
+#endif
+      in_send_(0),
+      off_the_record_(false) {
   SendUnblockingOnlyDuringDispatch();
   ChildProcess::current()->AddRefProcess();
   const CommandLine* command_line = CommandLine::ForCurrentProcess();
   log_messages_ = command_line->HasSwitch(switches::kLogPluginMessages);
 }
 
 PluginChannel::~PluginChannel() {
   if (renderer_handle_)
     base::CloseProcessHandle(renderer_handle_);
+#if defined(OS_POSIX)
+  // If we still have the FD, close it.
+  if (renderer_fd_ != -1) {
+    close(renderer_fd_);
+  }
+#endif
   ChildProcess::current()->ReleaseProcess();
 }
 
 bool PluginChannel::Send(IPC::Message* msg) {
   in_send_++;
   if (log_messages_) {
     LOG(INFO) << "sending message @" << msg << " on channel @" << this
               << " with type " << msg->type();
   }
   bool result = PluginChannelBase::Send(msg);
@@ skipping 75 matching lines @@
     RemoveRoute(plugin_stubs_[i]->instance_id());
 
   // Need to addref this object temporarily because otherwise removing the last
   // stub will cause the destructor of this object to be called, however at
   // that point plugin_stubs_ will have one element and its destructor will be
   // called twice.
   scoped_refptr<PluginChannel> me(this);
 
   plugin_stubs_.clear();
 }
+
+bool PluginChannel::Init(MessageLoop* ipc_message_loop, bool create_pipe_now) {
+#if defined(OS_POSIX)
+  // This gets called when the PluginChannel is initially created. At this
+  // point, create the socketpair and assign the plugin side FD to the channel
+  // name. Keep the renderer side FD as a member variable in the PluginChannel
+  // to be able to transmit it through IPC.
+  int plugin_fd;
+  IPC::SocketPair(&plugin_fd, &renderer_fd_);
+  IPC::AddChannelSocket(channel_name(), plugin_fd);
+#endif
+  return PluginChannelBase::Init(ipc_message_loop, create_pipe_now);
+}