First step towards moving AudioDevice from content/ to media/audio.

content/renderer/media/audio_device.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 "content/renderer/media/audio_device.h"
 
 #include "base/debug/trace_event.h"
 #include "base/message_loop.h"
 #include "base/threading/thread_restrictions.h"
 #include "base/time.h"
-#include "content/common/media/audio_messages.h"
-#include "content/common/view_messages.h"
 #include "media/audio/audio_output_controller.h"
 #include "media/audio/audio_util.h"
 
 using media::AudioRendererSink;
 
 // Takes care of invoking the render callback on the audio thread.
 // An instance of this class is created for each capture stream in
 // OnStreamCreated().
 class AudioDevice::AudioThreadCallback
     : public AudioDeviceThread::Callback {
  public:
   AudioThreadCallback(const media::AudioParameters& audio_parameters,
                       base::SharedMemoryHandle memory,
                       int memory_length,
                       AudioRendererSink::RenderCallback* render_callback);
   virtual ~AudioThreadCallback();
 
   virtual void MapSharedMemory() OVERRIDE;
 
   // Called whenever we receive notifications about pending data.
   virtual void Process(int pending_data) OVERRIDE;
 
  private:
   AudioRendererSink::RenderCallback* render_callback_;
   DISALLOW_COPY_AND_ASSIGN(AudioThreadCallback);
 };
 
 AudioDevice::AudioDevice(
+    media::AudioOutputIPC* ipc,
     const scoped_refptr<base::MessageLoopProxy>& io_loop)
     : ScopedLoopObserver(io_loop),
       callback_(NULL),
+      ipc_(ipc),
       stream_id_(0),
       play_on_start_(true),
       is_started_(false) {
-  // Use the filter instance already created on the main render thread.
-  CHECK(AudioMessageFilter::Get()) << "Invalid audio message filter.";
-  filter_ = AudioMessageFilter::Get();
+  CHECK(ipc_);
 }
 
 void AudioDevice::Initialize(const media::AudioParameters& params,
                              RenderCallback* callback) {
   CHECK_EQ(0, stream_id_) <<
       "AudioDevice::Initialize() must be called before Start()";
 
   CHECK(!callback_);  // Calling Initialize() twice?
 
   audio_parameters_ = params;
@@ skipping 45 matching lines @@
   return true;
 }
 
 void AudioDevice::CreateStreamOnIOThread(const media::AudioParameters& params) {
   DCHECK(message_loop()->BelongsToCurrentThread());
   // Make sure we don't create the stream more than once.
   DCHECK_EQ(0, stream_id_);
   if (stream_id_)
     return;
 
-  stream_id_ = filter_->AddDelegate(this);
-  Send(new AudioHostMsg_CreateStream(stream_id_, params));
+  stream_id_ = ipc_->AddDelegate(this);
+  ipc_->CreateStream(stream_id_, params);
 }
 
 void AudioDevice::PlayOnIOThread() {
   DCHECK(message_loop()->BelongsToCurrentThread());
   if (stream_id_ && is_started_)
-    Send(new AudioHostMsg_PlayStream(stream_id_));
+    ipc_->PlayStream(stream_id_);
   else
     play_on_start_ = true;
 }
 
 void AudioDevice::PauseOnIOThread(bool flush) {
   DCHECK(message_loop()->BelongsToCurrentThread());
   if (stream_id_ && is_started_) {
-    Send(new AudioHostMsg_PauseStream(stream_id_));
+    ipc_->PauseStream(stream_id_);
     if (flush)
-      Send(new AudioHostMsg_FlushStream(stream_id_));
+      ipc_->FlushStream(stream_id_);
   } else {
     // Note that |flush| isn't relevant here since this is the case where
     // the stream is first starting.
     play_on_start_ = false;
   }
 }
 
 void AudioDevice::ShutDownOnIOThread() {
   DCHECK(message_loop()->BelongsToCurrentThread());
 
   // Make sure we don't call shutdown more than once.
   if (stream_id_) {
     is_started_ = false;
 
-    filter_->RemoveDelegate(stream_id_);
-    Send(new AudioHostMsg_CloseStream(stream_id_));
+    ipc_->RemoveDelegate(stream_id_);
+    ipc_->CloseStream(stream_id_);
     stream_id_ = 0;
   }
 
   // We can run into an issue where ShutDownOnIOThread is called right after
   // OnStreamCreated is called in cases where Start/Stop are called before we
   // get the OnStreamCreated callback.  To handle that corner case, we call
   // Stop(). In most cases, the thread will already be stopped.
   // Another situation is when the IO thread goes away before Stop() is called
   // in which case, we cannot use the message loop to close the thread handle
   // and can't not rely on the main thread existing either.
   base::ThreadRestrictions::ScopedAllowIO allow_io;
   audio_thread_.Stop(NULL);
   audio_callback_.reset();
 }
 
 void AudioDevice::SetVolumeOnIOThread(double volume) {
   DCHECK(message_loop()->BelongsToCurrentThread());
   if (stream_id_)
-    Send(new AudioHostMsg_SetVolume(stream_id_, volume));
+    ipc_->SetVolume(stream_id_, volume);
 }
 
-void AudioDevice::OnStateChanged(AudioStreamState state) {
+void AudioDevice::OnStateChanged(media::AudioOutputIPCDelegate::State state) {
   DCHECK(message_loop()->BelongsToCurrentThread());
 
   // Do nothing if the stream has been closed.
   if (!stream_id_)
     return;
 
-  if (state == kAudioStreamError) {
+  if (state == media::AudioOutputIPCDelegate::kError) {
     DLOG(WARNING) << "AudioDevice::OnStateChanged(kError)";
     // Don't dereference the callback object if the audio thread
     // is stopped or stopping.  That could mean that the callback
     // object has been deleted.
     // TODO(tommi): Add an explicit contract for clearing the callback
     // object.  Possibly require calling Initialize again or provide
     // a callback object via Start() and clear it in Stop().
     if (!audio_thread_.IsStopped())
       callback_->OnRenderError();
   }
 }
 
 void AudioDevice::OnStreamCreated(
     base::SharedMemoryHandle handle,
     base::SyncSocket::Handle socket_handle,
-    uint32 length) {
+    int length) {
   DCHECK(message_loop()->BelongsToCurrentThread());
-  // TODO(vrk): Remove cast when |length| is int instead of uint32.
-  DCHECK_GE(length, static_cast<uint32>(audio_parameters_.GetBytesPerBuffer()));
+  DCHECK_GE(length, audio_parameters_.GetBytesPerBuffer());
 #if defined(OS_WIN)
   DCHECK(handle);
   DCHECK(socket_handle);
 #else
   DCHECK_GE(handle.fd, 0);
   DCHECK_GE(socket_handle, 0);
 #endif
 
   base::AutoLock auto_lock(audio_thread_lock_);
 
@@ skipping 10 matching lines @@
       handle, length, callback_));
   audio_thread_.Start(audio_callback_.get(), socket_handle, "AudioDevice");
 
   // We handle the case where Play() and/or Pause() may have been called
   // multiple times before OnStreamCreated() gets called.
   is_started_ = true;
   if (play_on_start_)
     PlayOnIOThread();
 }
 
-void AudioDevice::Send(IPC::Message* message) {
-  filter_->Send(message);
+void AudioDevice::OnIPCClosed() {
+  ipc_ = NULL;
 }
 
 void AudioDevice::WillDestroyCurrentMessageLoop() {
   LOG(ERROR) << "IO loop going away before the audio device has been stopped";
   ShutDownOnIOThread();
 }
 
 // AudioDevice::AudioThreadCallback
 
 AudioDevice::AudioThreadCallback::AudioThreadCallback(
@@ skipping 33 matching lines @@
   // Interleave, scale, and clip to int.
   // TODO(crogers/vrk): Figure out a way to avoid the float -> int -> float
   // conversions that happen in the <audio> and WebRTC scenarios.
   media::InterleaveFloatToInt(audio_data_, shared_memory_.memory(),
       num_frames, audio_parameters_.bits_per_sample() / 8);
 
   // Let the host know we are done.
   media::SetActualDataSizeInBytes(&shared_memory_, memory_length_,
       num_frames * audio_parameters_.GetBytesPerFrame());
 }