GPU plugin forwards repaint events to Pepper plugin.

WM_PAINT results in a call to Pepper repaint callback.
Implemented WM_ERASEBKGND to prevent flickering on repaint.
Implemented PGL_NO_CONTEXT (copied from EGL spec). This is already reviewed by alokp but unfortunately got entangled with this CL.

TEST=none
BUG=none

Review URL: http://codereview.chromium.org/571018

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@39530 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 149 insertions, 24 deletions

diff --git a/chrome/plugin/command_buffer_stub.cc b/chrome/plugin/command_buffer_stub.cc
index e6f4b76..21e53e3 100644
--- a/chrome/plugin/command_buffer_stub.cc
+++ b/chrome/plugin/command_buffer_stub.cc
@@ -3,7 +3,7 @@
 // found in the LICENSE file.
 
 #include "base/callback.h"
-#include "base/process_util.h"
+#include "base/scoped_open_process.h"
 #include "base/shared_memory.h"
 #include "chrome/common/command_buffer_messages.h"
 #include "chrome/common/plugin_messages.h"
@@ -23,6 +23,7 @@ CommandBufferStub::CommandBufferStub(PluginChannel* channel,
 }
 
 CommandBufferStub::~CommandBufferStub() {
+  Destroy();
   channel_->RemoveRoute(route_id_);
 }
 
@@ -67,35 +68,54 @@ void CommandBufferStub::OnInitialize(int32 size,
 
   // Assume service is responsible for duplicating the handle from the calling
   // process.
-  base::ProcessHandle peer_handle;
-  if (!base::OpenProcessHandle(channel_->peer_pid(), &peer_handle))
+  base::ScopedOpenProcess peer_process;
+  if (!peer_process.Open(channel_->peer_pid()))
     return;
 
   command_buffer_.reset(new gpu::CommandBufferService);
 
-  // Initialize the CommandBufferService and GPUProcessor.
-  if (command_buffer_->Initialize(size)) {
-    Buffer buffer = command_buffer_->GetRingBuffer();
-    if (buffer.shared_memory) {
-      processor_ = new gpu::GPUProcessor(command_buffer_.get());
-      if (processor_->Initialize(window_)) {
-        command_buffer_->SetPutOffsetChangeCallback(
-            NewCallback(processor_.get(),
-                        &gpu::GPUProcessor::ProcessCommands));
-#if defined(OS_MACOSX)
-        processor_->SetSwapBuffersCallback(
-            NewCallback(this,
-                        &CommandBufferStub::SwapBuffersCallback));
-#endif
-        buffer.shared_memory->ShareToProcess(peer_handle, ring_buffer);
-      } else {
-        processor_ = NULL;
-        command_buffer_.reset();
-      }
-    }
+  // Initialize the CommandBufferService.
+  if (!command_buffer_->Initialize(size)) {
+    Destroy();
+    return;
   }
 
-  base::CloseProcessHandle(peer_handle);
+  // Get the ring buffer.
+  Buffer buffer = command_buffer_->GetRingBuffer();
+  if (!buffer.shared_memory) {
+    Destroy();
+    return;
+  }
+
+  // Initialize the GPUProcessor.
+  processor_ = new gpu::GPUProcessor(command_buffer_.get());
+  if (!processor_->Initialize(window_)) {
+    Destroy();
+    return;
+  }
+
+  // Perform platform specific initialization.
+  if (!InitializePlatformSpecific()) {
+    Destroy();
+    return;
+  }
+
+  // Share the ring buffer to the client process.
+  if (!buffer.shared_memory->ShareToProcess(peer_process.handle(),
+                                            ring_buffer)) {
+    Destroy();
+    return;
+  }
+
+  // Setup callbacks for events.
+  command_buffer_->SetPutOffsetChangeCallback(
+      NewCallback(processor_.get(),
+                  &gpu::GPUProcessor::ProcessCommands));
+#if defined(OS_MACOSX)
+  processor_->SetSwapBuffersCallback(
+      NewCallback(this,
+                  &CommandBufferStub::SwapBuffersCallback));
+#endif
 }
 
 void CommandBufferStub::OnGetState(gpu::CommandBuffer::State* state) {
@@ -147,6 +167,22 @@ void CommandBufferStub::OnGetTransferBuffer(
   base::CloseProcessHandle(peer_handle);
 }
 
+void CommandBufferStub::Destroy() {
+  processor_ = NULL;
+  command_buffer_.reset();
+
+  DestroyPlatformSpecific();
+}
+
+#if !defined(OS_WIN)
+bool CommandBufferStub::InitializePlatformSpecific() {
+  return true;
+}
+
+void CommandBufferStub::DestroyPlatformSpecific() {
+}
+#endif  // defined(OS_WIN)
+
 #if defined(OS_MACOSX)
 void CommandBufferStub::OnSetWindowSize(int32 width, int32 height) {
   uint64 new_backing_store = processor_->SetWindowSize(width, height);
diff --git a/chrome/plugin/command_buffer_stub.h b/chrome/plugin/command_buffer_stub.h
index f0d8ac0..f7bd691 100644
--- a/chrome/plugin/command_buffer_stub.h
+++ b/chrome/plugin/command_buffer_stub.h
@@ -37,6 +37,10 @@ class CommandBufferStub : public IPC::Channel::Listener,
 
   int route_id() const { return route_id_; }
 
+  // Notify the client that it must repaint due to the window becoming invalid
+  // or a lost context.
+  void NotifyRepaint();
+
  private:
   // Message handlers:
   void OnInitialize(int32 size, base::SharedMemoryHandle* ring_buffer);
@@ -49,6 +53,13 @@ class CommandBufferStub : public IPC::Channel::Listener,
   void OnGetTransferBuffer(int32 id,
                            base::SharedMemoryHandle* transfer_buffer,
                            uint32* size);
+
+  // Destroy all owned objects.
+  void Destroy();
+
+  bool InitializePlatformSpecific();
+  void DestroyPlatformSpecific();
+
 #if defined(OS_MACOSX)
   void OnSetWindowSize(int32 width, int32 height);
   void SwapBuffersCallback();
diff --git a/chrome/plugin/command_buffer_stub_win.cc b/chrome/plugin/command_buffer_stub_win.cc
new file mode 100644
index 0000000..656bbd1
--- /dev/null
+++ b/chrome/plugin/command_buffer_stub_win.cc
@@ -0,0 +1,78 @@
+// 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 <windows.h>
+
+#include "chrome/common/command_buffer_messages.h"
+#include "chrome/plugin/command_buffer_stub.h"
+
+namespace {
+const wchar_t* kPreviousWndProcProperty = L"CommandBufferStubPrevWndProc";
+const wchar_t* kCommandBufferStubProperty = L"CommandBufferStub";
+
+// Message handler for the GPU plugin's child window. Used to intercept
+// WM_PAINT events and forward repaint notifications to the client.
+LRESULT WINAPI WndProc(HWND handle,
+                       UINT message,
+                       WPARAM w_param,
+                       LPARAM l_param) {
+  WNDPROC previous_wnd_proc = reinterpret_cast<WNDPROC>(
+      ::GetProp(handle, kPreviousWndProcProperty));
+  CommandBufferStub* stub = reinterpret_cast<CommandBufferStub*>(
+      ::GetProp(handle, kCommandBufferStubProperty));
+
+  switch (message) {
+    case WM_ERASEBKGND:
+      // Do not clear background. Avoids flickering.
+      return 1;
+    case WM_PAINT:
+      // Validate the whole window to prevent another WM_PAINT message.
+      ValidateRect(handle, NULL);
+
+      // Notify client that the window is invalid and needs to be repainted.
+      stub->NotifyRepaint();
+
+      return 1;
+    default:
+      return CallWindowProc(previous_wnd_proc,
+                            handle,
+                            message,
+                            w_param,
+                            l_param);
+  }
+}
+}  // namespace anonymous
+
+void CommandBufferStub::NotifyRepaint() {
+  Send(new CommandBufferMsg_NotifyRepaint(route_id_));
+}
+
+bool CommandBufferStub::InitializePlatformSpecific() {
+  // Subclass window.
+  WNDPROC previous_wnd_proc = reinterpret_cast<WNDPROC>(
+      ::GetWindowLongPtr(window_, GWLP_WNDPROC));
+  ::SetProp(window_,
+            kPreviousWndProcProperty,
+            reinterpret_cast<HANDLE>(previous_wnd_proc));
+  ::SetWindowLongPtr(window_,
+                     GWLP_WNDPROC,
+                     reinterpret_cast<LONG_PTR>(WndProc));
+
+  // Record pointer to this in window.
+  ::SetProp(window_,
+            kCommandBufferStubProperty,
+            reinterpret_cast<HANDLE>(this));
+
+  return true;
+}
+
+void CommandBufferStub::DestroyPlatformSpecific() {
+  // Restore window.
+  WNDPROC previous_wnd_proc = reinterpret_cast<WNDPROC>(
+      ::GetProp(window_, kPreviousWndProcProperty));
+  ::SetWindowLongPtr(window_, GWLP_WNDPROC, reinterpret_cast<LONG_PTR>(
+      previous_wnd_proc));
+  ::RemoveProp(window_, kPreviousWndProcProperty);
+  ::RemoveProp(window_, kCommandBufferStubProperty);
+}