Tab Audio Mirroring: WebContentsAudioInputStream is a new implementation which represents the lifet…

media/audio/audio_input_controller.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 "media/audio/audio_input_controller.h"
 
 #include "base/bind.h"
 #include "base/threading/thread_restrictions.h"
 #include "media/base/limits.h"
 
@@ skipping 83 matching lines @@
   // audio-device thread. Use the provided audio-input device.
   if (!controller->message_loop_->PostTask(FROM_HERE,
           base::Bind(&AudioInputController::DoCreate, controller,
                      base::Unretained(audio_manager), params, device_id))) {
     controller = NULL;
   }
 
   return controller;
 }
 
+// static
+scoped_refptr<AudioInputController> AudioInputController::CreateForStream(
+    AudioManager* audio_manager,
+    EventHandler* event_handler,
+    AudioInputStream* stream,
+    SyncWriter* sync_writer) {
+  DCHECK(audio_manager);
+  DCHECK(sync_writer);
+  DCHECK(stream);
+
+  // Create the AudioInputController object and ensure that it runs on
+  // the audio-manager thread.
+  scoped_refptr<AudioInputController> controller(new AudioInputController(
+      event_handler, sync_writer));
+  controller->message_loop_ = audio_manager->GetMessageLoop();
+
+  controller->stream_ = stream;

[DaleCurtis, 2013/01/15 22:02:18]

Seems like it might be clearer to make a DoCreate() or DoFinishCreate() take a
stream input to ensure assumptions about what DoCreate() is doing don't change.

I'm not really crazy about the static setting message_loop_ either.
AudioInputController has access to the AudioManager.

[miu, 2013/01/16 03:22:18]

Done.  I renamed DoFinishCreate() to DoCreateForStream(), and I pass in the
stream as as argument.

As for the message_loop_ thing...Yeah it's ugly.  I noticed that, and several
other things.  I'd like to tackle cleaning up AudioInputController (it doesn't
even have any unit tests).  I'd prefer to do this in a future change, though. 
SGTY?

+
+  if (!controller->message_loop_->PostTask(
+          FROM_HERE,
+          base::Bind(&AudioInputController::DoFinishCreate, controller))) {
+    controller = NULL;
+  }
+
+  return controller;
+}
+
 void AudioInputController::Record() {
   message_loop_->PostTask(FROM_HERE, base::Bind(
       &AudioInputController::DoRecord, this));
 }
 
 void AudioInputController::Close(const base::Closure& closed_task) {
   DCHECK(!closed_task.is_null());
   DCHECK(creator_loop_->BelongsToCurrentThread());
 
   message_loop_->PostTaskAndReply(
@@ skipping 10 matching lines @@
       &AudioInputController::DoSetAutomaticGainControl, this, enabled));
 }
 
 void AudioInputController::DoCreate(AudioManager* audio_manager,
                                     const AudioParameters& params,
                                     const std::string& device_id) {
   DCHECK(message_loop_->BelongsToCurrentThread());
 
   stream_ = audio_manager->MakeAudioInputStream(params, device_id);
 
+  DoFinishCreate();
+}
+
+void AudioInputController::DoFinishCreate() {
+  DCHECK(message_loop_->BelongsToCurrentThread());
+
   if (!stream_) {
     // TODO(satish): Define error types.
     handler_->OnError(this, 0);
     return;
   }
 
   if (stream_ && !stream_->Open()) {
     stream_->Close();
     stream_ = NULL;
     // TODO(satish): Define error types.
@@ skipping 166 matching lines @@
 
 void AudioInputController::SetDataIsActive(bool enabled) {
   base::subtle::Release_Store(&data_is_active_, enabled);
 }
 
 bool AudioInputController::GetDataIsActive() {
   return (base::subtle::Acquire_Load(&data_is_active_) != false);
 }
 
 }  // namespace media