Cast: Refactoring Cast API's

chrome/renderer/media/cast_session_delegate.cc

Index: chrome/renderer/media/cast_session_delegate.cc
diff --git a/chrome/renderer/media/cast_session_delegate.cc b/chrome/renderer/media/cast_session_delegate.cc
index 5da3443f493cb3339e0c6ce789e1a66776af4f78..f014638a9775029f5273664a0fad55d32ca8930f 100644
--- a/chrome/renderer/media/cast_session_delegate.cc
+++ b/chrome/renderer/media/cast_session_delegate.cc
@@ -70,15 +70,6 @@ CastSessionDelegate::CastSessionDelegate()
       video_encode_thread_("CastVideoEncodeThread"),
       io_message_loop_proxy_(
           content::RenderThread::Get()->GetIOMessageLoopProxy()) {
-}
-
-CastSessionDelegate::~CastSessionDelegate() {
-  DCHECK(io_message_loop_proxy_->BelongsToCurrentThread());
-}
-
-void CastSessionDelegate::Initialize() {
-  if (cast_environment_)
-    return;  // Already initialized.
 
   cast_transport_.reset(new DummyTransport());
   audio_encode_thread_.Start();
@@ -97,6 +88,15 @@ void CastSessionDelegate::Initialize() {
       NULL,
       base::MessageLoopProxy::current(),
       media::cast::GetDefaultCastSenderLoggingConfig());
+  cast_sender_.reset(CastSender::CreateCastSender(
+      cast_environment_,
+      base::Bind(&CastSessionDelegate::InitializationResult,
+                 base::Unretained(this)),

[Ami GONE FROM CHROMIUM, 2014/02/13 18:02:14]

What makes this Unretained safe?
Is it that this bound callback is only invoked on the IO thread and only as a
result of calling Initialize{Audio,Video} on the IO thread, and that
synchronously, and the dtor DCHECKing that this is only deleted on the IO
thread?
Because if the answer is yeah, the above, it might be worth describing in a note
:)

[Alpha Left Google, 2014/02/13 19:53:59]

I too this this needs an explanation.

Please make sure the callback is called on the cast main thread. If it happens
asynchronously this should be a weak pointer.

[mikhal1, 2014/02/14 18:03:16]

Switching to a weak ptr.
On 2014/02/13 19:53:59, Alpha wrote:

+      cast_transport_.get()));
+}
+
+CastSessionDelegate::~CastSessionDelegate() {
+  DCHECK(io_message_loop_proxy_->BelongsToCurrentThread());
 }
 
 void CastSessionDelegate::StartAudio(
@@ -104,8 +104,9 @@ void CastSessionDelegate::StartAudio(
     const FrameInputAvailableCallback& callback) {
   DCHECK(io_message_loop_proxy_->BelongsToCurrentThread());
 
-  audio_config_.reset(new AudioSenderConfig(config));
-  StartSendingInternal(callback, true);
+  cast_sender_->InitializeAudio(config);
+  audio_frame_input_available_callback_.reset(
+        new FrameInputAvailableCallback(callback));
 }
 
 void CastSessionDelegate::StartVideo(
@@ -113,33 +114,10 @@ void CastSessionDelegate::StartVideo(
     const FrameInputAvailableCallback& callback) {
   DCHECK(io_message_loop_proxy_->BelongsToCurrentThread());
 
-  video_config_.reset(new VideoSenderConfig(config));
-  StartSendingInternal(callback, false);
-}
-
-void CastSessionDelegate::StartSendingInternal(
-    const FrameInputAvailableCallback& callback,
-    bool is_audio) {
-  DCHECK(io_message_loop_proxy_->BelongsToCurrentThread());
-
-  Initialize();
-
-  if (is_audio) {
-    audio_frame_input_available_callback_.reset(
-        new FrameInputAvailableCallback(callback));
-  } else {
-    video_frame_input_available_callback_.reset(
+  // Initialize video - set gpu to NULL.
+  cast_sender_->InitializeVideo(config, NULL);
+  video_frame_input_available_callback_.reset(
         new FrameInputAvailableCallback(callback));
-  }
-
-  cast_sender_.reset(CastSender::CreateCastSender(
-      cast_environment_,
-      audio_config_.get(),
-      video_config_.get(),
-      NULL,  // GPU.
-      base::Bind(&CastSessionDelegate::InitializationResult,
-                 base::Unretained(this)),
-      cast_transport_.get()));
 }
 
 void CastSessionDelegate::InitializationResult(
@@ -147,12 +125,11 @@ void CastSessionDelegate::InitializationResult(
   DCHECK(cast_sender_);
 
   // TODO(pwestin): handle the error codes.
-  if (result == media::cast::STATUS_INITIALIZED) {
-    if (audio_frame_input_available_callback_) {
+  if (result == media::cast::STATUS_AUDIO_INITIALIZED) {
+    if (audio_frame_input_available_callback_)
       audio_frame_input_available_callback_->Run(cast_sender_->frame_input());
-    }
-    if (video_frame_input_available_callback_) {
+  } else if (result == media::cast::STATUS_VIDEO_INITIALIZED) {
+    if (video_frame_input_available_callback_)
       video_frame_input_available_callback_->Run(cast_sender_->frame_input());
-    }
   }
 }