Added command buffer implementation of WebGL which runs in the sandbox....

chrome/browser/gpu_process_host.cc

 // 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 "chrome/browser/gpu_process_host.h"
 
 #include "base/command_line.h"
 #include "base/singleton.h"
 #include "base/thread.h"
 #include "chrome/browser/browser_process.h"
@@ skipping 44 matching lines @@
 #elif defined(POSIX)
       false,  // Never use the zygote (GPU plugin can't be sandboxed).
       base::environment_vector(),
       channel_->GetClientFileDescriptor(),
 #endif
       cmd_line,
       this));
 }
 
 GpuProcessHost::~GpuProcessHost() {
+  while (!queued_synchronization_replies_.empty()) {
+    delete queued_synchronization_replies_.front();
+    queued_synchronization_replies_.pop();
+  }
 }
 
 // static
 GpuProcessHost* GpuProcessHost::Get() {
   GpuProcessHost* host = Singleton<GpuProcessHost>::get();
   if (!host->child_process_.get())
     return NULL;  // Failed to init.
   return host;
 }
 
@@ skipping 51 matching lines @@
   router_.RemoveRoute(routing_id);
 }
 
 void GpuProcessHost::EstablishGpuChannel(int renderer_id) {
   if (Send(new GpuMsg_EstablishChannel(renderer_id)))
     sent_requests_.push(ChannelRequest(renderer_id));
   else
     ReplyToRenderer(renderer_id, IPC::ChannelHandle());
 }
 
+void GpuProcessHost::Synchronize(int renderer_id, IPC::Message* reply) {
+  // ************
+  // TODO(kbr): the handling of this synchronous message (which is
+  // needed for proper initialization semantics of APIs like WebGL) is
+  // currently broken on Windows because the renderer is sending a
+  // synchronous message to the browser's UI thread. To fix this, the
+  // GpuProcessHost needs to move to the IO thread, and any backing
+  // store handling needs to remain on the UI thread in a new
+  // GpuProcessHostProxy, where work is sent from the IO thread to the
+  // UI thread via PostTask.
+  // ************
+  queued_synchronization_replies_.push(reply);
+  CHECK(Send(new GpuMsg_Synchronize(renderer_id)));
+}
+
 void GpuProcessHost::OnControlMessageReceived(const IPC::Message& message) {
   IPC_BEGIN_MESSAGE_MAP(GpuProcessHost, message)
     IPC_MESSAGE_HANDLER(GpuHostMsg_ChannelEstablished, OnChannelEstablished)
+    IPC_MESSAGE_HANDLER(GpuHostMsg_SynchronizeReply, OnSynchronizeReply)
     IPC_MESSAGE_UNHANDLED_ERROR()
   IPC_END_MESSAGE_MAP()
 }
 
 void GpuProcessHost::OnChannelEstablished(
     const IPC::ChannelHandle& channel_handle) {
   const ChannelRequest& request = sent_requests_.front();
 
   ReplyToRenderer(request.renderer_id, channel_handle);
   sent_requests_.pop();
 }
 
+void GpuProcessHost::OnSynchronizeReply(int renderer_id) {
+  IPC::Message* reply = queued_synchronization_replies_.front();
+  queued_synchronization_replies_.pop();
+  RenderProcessHost* process_host = RenderProcessHost::FromID(renderer_id);
+  if (!process_host) {
+    delete reply;
+    return;
+  }
+  CHECK(process_host->Send(reply));
+}
+
 void GpuProcessHost::ReplyToRenderer(
     int renderer_id,
     const IPC::ChannelHandle& channel) {
   // Check whether the renderer process is still around.
   RenderProcessHost* process_host = RenderProcessHost::FromID(renderer_id);
   if (!process_host)
     return;
 
-  CHECK(process_host->Send(new ViewMsg_GpuChannelEstablished(channel)));
+  ViewMsg_GpuChannelEstablished* msg =
+      new ViewMsg_GpuChannelEstablished(channel);
+  // If the renderer process is performing synchronous initialization,
+  // it needs to handle this message before receiving the reply for
+  // the synchronous ViewHostMsg_SynchronizeGpu message.
+  msg->set_unblock(true);
+  CHECK(process_host->Send(msg));
 }
 
 void GpuProcessHost::PropagateBrowserCommandLineToGpu(
     const CommandLine& browser_cmd,
     CommandLine* gpu_cmd) const {
   // Propagate the following switches to the GPU process command line (along
   // with any associated values) if present in the browser command line.
   static const char* const switch_names[] = {
     switches::kDisableLogging,
     switches::kEnableLogging,
     switches::kGpuStartupDialog,
     switches::kLoggingLevel,
   };
 
   for (size_t i = 0; i < arraysize(switch_names); ++i) {
     if (browser_cmd.HasSwitch(switch_names[i])) {
       gpu_cmd->AppendSwitchWithValue(switch_names[i],
           browser_cmd.GetSwitchValueASCII(switch_names[i]));
     }
   }
 }