MediaStream audio: Refactor 3 separate "glue" implementations into one.

content/renderer/media/media_stream_audio_track.cc

Index: content/renderer/media/media_stream_audio_track.cc
diff --git a/content/renderer/media/media_stream_audio_track.cc b/content/renderer/media/media_stream_audio_track.cc
index 9eee57d61428d6146bda28f8c930294a8f84857e..efe17b252b702008bb25c5464a5ec1c14ccaa197 100644
--- a/content/renderer/media/media_stream_audio_track.cc
+++ b/content/renderer/media/media_stream_audio_track.cc
@@ -4,15 +4,17 @@
 
 #include "content/renderer/media/media_stream_audio_track.h"
 
+#include <algorithm>
+
 #include "base/callback_helpers.h"
 #include "base/logging.h"
+#include "content/public/renderer/media_stream_audio_sink.h"
 #include "third_party/WebKit/public/platform/WebMediaStreamSource.h"
-#include "third_party/webrtc/api/mediastreaminterface.h"
 
 namespace content {
 
 MediaStreamAudioTrack::MediaStreamAudioTrack(bool is_local_track)
-    : MediaStreamTrack(is_local_track) {
+    : MediaStreamTrack(is_local_track), is_enabled_(true), weak_factory_(this) {
   DVLOG(1) << "MediaStreamAudioTrack::MediaStreamAudioTrack(is a "
            << (is_local_track ? "local" : "remote") << " track)";
 }
@@ -34,6 +36,56 @@ MediaStreamAudioTrack* MediaStreamAudioTrack::From(
   return static_cast<MediaStreamAudioTrack*>(track.getExtraData());
 }
 
+void MediaStreamAudioTrack::AddSink(MediaStreamAudioSink* sink) {
+  DCHECK(main_render_thread_checker_.CalledOnValidThread());
+  DCHECK(sink);
+  DVLOG(1) << "MediaStreamAudioTrack::AddSink(" << sink << ')';
+  {
+    base::AutoLock auto_lock(lock_);
+    DCHECK(std::find(sinks_.begin(), sinks_.end(), sink) == sinks_.end());
+    DCHECK(std::find(pending_sinks_.begin(), pending_sinks_.end(), sink) ==
+           pending_sinks_.end());
+    pending_sinks_.push_back(sink);
+  }
+}
+
+void MediaStreamAudioTrack::RemoveSink(MediaStreamAudioSink* sink) {
+  DCHECK(main_render_thread_checker_.CalledOnValidThread());
+  {
+    base::AutoLock auto_lock(lock_);
+    auto it = std::find(pending_sinks_.begin(), pending_sinks_.end(), sink);
+    if (it != pending_sinks_.end()) {
+      DVLOG(1) << "MediaStreamAudioTrack::RemoveSink(" << sink
+               << ") from pending sinks list.";
+      pending_sinks_.erase(it);
+    } else {
+      it = std::find(sinks_.begin(), sinks_.end(), sink);
+      if (it != sinks_.end()) {
+        DVLOG(1) << "MediaStreamAudioTrack::RemoveSink(" << sink
+                 << ") from active sinks list.";
+        sinks_.erase(it);
+      }
+    }
+  }
+}
+
+media::AudioParameters MediaStreamAudioTrack::GetOutputFormat() const {
+  base::AutoLock auto_lock(lock_);
+  return params_;
+}
+
+void MediaStreamAudioTrack::SetEnabled(bool enabled) {
+  DCHECK(main_render_thread_checker_.CalledOnValidThread());
+  base::AutoLock auto_lock(lock_);
+  DVLOG(1) << "MediaStreamAudioTrack::SetEnabled(" << (enabled ? 'Y' : 'N')
+           << "), was previously set to " << (is_enabled_ ? 'Y' : 'N') << '.';
+  is_enabled_ = enabled;
+}
+
+void* MediaStreamAudioTrack::GetClassIdentifier() const {
+  return nullptr;
+}
+
 void MediaStreamAudioTrack::Start(const base::Closure& stop_callback) {
   DCHECK(main_render_thread_checker_.CalledOnValidThread());
   DCHECK(!stop_callback.is_null());
@@ -45,16 +97,60 @@ void MediaStreamAudioTrack::Start(const base::Closure& stop_callback) {
 void MediaStreamAudioTrack::Stop() {
   DCHECK(main_render_thread_checker_.CalledOnValidThread());
   DVLOG(1) << "MediaStreamAudioTrack::Stop()";
+
   if (!stop_callback_.is_null())
     base::ResetAndReturn(&stop_callback_).Run();
+
   OnStop();
+
+  std::vector<MediaStreamAudioSink*> sinks_to_notify;
+  {
+    base::AutoLock auto_lock(lock_);
+    sinks_to_notify.swap(sinks_);
+    sinks_to_notify.insert(sinks_to_notify.end(), pending_sinks_.begin(),
+                           pending_sinks_.end());
+    pending_sinks_.clear();
+  }
+  for (MediaStreamAudioSink* sink : sinks_to_notify)
+    sink->OnReadyStateChanged(blink::WebMediaStreamSource::ReadyStateEnded);
+
+  weak_factory_.InvalidateWeakPtrs();
 }
 
 void MediaStreamAudioTrack::OnStop() {}
 
-webrtc::AudioTrackInterface* MediaStreamAudioTrack::GetAudioAdapter() {
-  NOTREACHED();
-  return nullptr;
+void MediaStreamAudioTrack::SetFormat(const media::AudioParameters& params) {
+  // Note: May be called on any thread.
+  base::AutoLock auto_lock(lock_);

[o1ka, 2016/03/30 15:00:58]

According to the header comment, lock_ is not supposed to protect params_

[miu, 2016/03/31 04:57:59]

Fixed header comment.

+  if (params_.Equals(params))
+    return;
+  params_ = params;
+  pending_sinks_.insert(pending_sinks_.end(), sinks_.begin(), sinks_.end());
+  sinks_.clear();
+}
+
+void MediaStreamAudioTrack::DeliverDataToSinks(const media::AudioBus& audio_bus,
+                                               base::TimeTicks reference_time) {
+  // Note: May be called on any thread.
+  base::AutoLock auto_lock(lock_);
+
+  // If audio delivery is currently disabled, take no actions.
+  if (!is_enabled_)
+    return;
+
+  // Call OnSetFormat() for all pending sinks and move them to the
+  // active-delivery list.
+  DCHECK(params_.IsValid());
+  if (!pending_sinks_.empty()) {
+    for (MediaStreamAudioSink* sink : pending_sinks_)
+      sink->OnSetFormat(params_);
+    sinks_.insert(sinks_.end(), pending_sinks_.begin(), pending_sinks_.end());
+    pending_sinks_.clear();
+  }
+
+  // Deliver the audio data to each sink.
+  for (MediaStreamAudioSink* sink : sinks_)
+    sink->OnData(audio_bus, reference_time);
 }
 
 }  // namespace content