Introduce PPB_Flash_MessageLoop interface for Pepper Flash.

webkit/plugins/ppapi/ppb_flash_message_loop_impl.cc

+// Copyright (c) 2012 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 "webkit/plugins/ppapi/ppb_flash_message_loop_impl.h"
+
+#include "base/message_loop.h"
+#include "ppapi/c/pp_errors.h"
+
+using ppapi::thunk::PPB_Flash_MessageLoop_API;
+
+namespace webkit {
+namespace ppapi {
+
+class PPB_Flash_MessageLoop_Impl::State
+    : public RefCounted<PPB_Flash_MessageLoop_Impl::State> {
+ public:
+  State() : result_(PP_ERROR_ABORTED),
+            run_called_(false),
+            quit_called_(false),
+            run_callback_(PP_BlockUntilComplete()) {
+  }
+
+  int32_t result() const { return result_; }
+  void set_result(int32_t result) { result_ = result; }
+
+  bool run_called() const { return run_called_; }
+  void set_run_called() { run_called_ = true; }
+
+  bool quit_called() const { return quit_called_; }
+  void set_quit_called() { quit_called_ = true; }
+
+  const PP_CompletionCallback& run_callback() const { return run_callback_; }
+  void set_run_callback(const PP_CompletionCallback& run_callback) {
+    run_callback_ = run_callback;
+  }
+
+ private:
+  int32_t result_;
+  bool run_called_;
+  bool quit_called_;
+  PP_CompletionCallback run_callback_;
+};
+
+PPB_Flash_MessageLoop_Impl::PPB_Flash_MessageLoop_Impl(PP_Instance instance)
+    : Resource(instance),
+      state_(new State()) {
+}
+
+PPB_Flash_MessageLoop_Impl::~PPB_Flash_MessageLoop_Impl() {
+  // It is a no-op if either Run() hasn't been called or Quit() has been called
+  // to balance the call to Run().
+  InternalQuit(PP_ERROR_ABORTED);
+}
+
+// static
+PP_Resource PPB_Flash_MessageLoop_Impl::Create(PP_Instance instance) {
+  return (new PPB_Flash_MessageLoop_Impl(instance))->GetReference();
+}
+
+PPB_Flash_MessageLoop_API*
+    PPB_Flash_MessageLoop_Impl::AsPPB_Flash_MessageLoop_API() {
+  return this;
+}
+
+int32_t PPB_Flash_MessageLoop_Impl::Run() {
+  return InternalRun(PP_BlockUntilComplete());

[viettrungluu, 2012/01/17 21:26:06]

Using PP_BlockUntilComplete seems kind of hacky (and misleading?) to me.

[yzshen1, 2012/01/18 07:43:35]

Thanks. I changed to PP_MakeCompletionCallback. And added comments for
InternalRun() in the .h file.

+}
+
+void PPB_Flash_MessageLoop_Impl::RunFromHostProxy(
+    PP_CompletionCallback callback) {
+  if (!callback.func)

[viettrungluu, 2012/01/17 21:26:06]

Should this even happen?

[yzshen1, 2012/01/18 07:43:35]

Removed. It shouldn't happen. And it is the caller's responsibility to make sure
that a valid callback is used, if it wants to be notified.

+    return;
+  InternalRun(callback);
+}
+
+void PPB_Flash_MessageLoop_Impl::Quit() {
+  InternalQuit(PP_OK);
+}
+
+int32_t PPB_Flash_MessageLoop_Impl::InternalRun(
+    PP_CompletionCallback callback) {
+  if (state_->run_called()) {
+    if (callback.func)
+      PP_RunCompletionCallback(&callback, PP_ERROR_FAILED);
+    return PP_ERROR_FAILED;
+  }
+  state_->set_run_called();
+  state_->set_run_callback(callback);
+
+  // It is possible that the PPB_Flash_MessageLoop_Impl object has been
+  // destroyed when the nested message loop exits.
+  scoped_refptr<State> state_protector(state_);
+
+  bool old_value = MessageLoop::current()->NestableTasksAllowed();
+  MessageLoop::current()->SetNestableTasksAllowed(true);
+  MessageLoop::current()->Run();
+
+  // Don't access data members of the class below.
+
+  MessageLoop::current()->SetNestableTasksAllowed(old_value);
+  return state_protector->result();
+}
+
+void PPB_Flash_MessageLoop_Impl::InternalQuit(int32_t result) {
+  if (!state_->run_called() || state_->quit_called())
+    return;
+  state_->set_quit_called();
+  state_->set_result(result);
+
+  MessageLoop::current()->QuitNow();
+
+  PP_CompletionCallback callback = state_->run_callback();
+  if (callback.func)
+    PP_RunCompletionCallback(&callback, result);
+}
+
+}  // namespace ppapi
+}  // namespace webkit