Support configuring number of audio buffers in MediaStream Pepper API.

content/renderer/pepper/pepper_media_stream_audio_track_host.h

 // Copyright 2014 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.
 
 #ifndef CONTENT_RENDERER_PEPPER_PEPPER_MEDIA_STREAM_AUDIO_TRACK_HOST_H_
 #define CONTENT_RENDERER_PEPPER_PEPPER_MEDIA_STREAM_AUDIO_TRACK_HOST_H_
 
 #include <deque>
 
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/synchronization/lock.h"
 #include "base/threading/thread_checker.h"
 #include "content/public/renderer/media_stream_audio_sink.h"
 #include "content/renderer/pepper/pepper_media_stream_track_host_base.h"
 #include "media/audio/audio_parameters.h"
+#include "ppapi/shared_impl/media_stream_audio_track_shared.h"
 #include "third_party/WebKit/public/platform/WebMediaStreamTrack.h"
 
 namespace base {
 class MessageLoopProxy;
 }  // namespace base
 
 namespace content {
 
 class PepperMediaStreamAudioTrackHost : public PepperMediaStreamTrackHostBase {
  public:
   PepperMediaStreamAudioTrackHost(RendererPpapiHost* host,
                                   PP_Instance instance,
                                   PP_Resource resource,
                                   const blink::WebMediaStreamTrack& track);
 
  private:
   // A helper class for receiving audio samples in the audio thread.
   // This class is created and destroyed on the renderer main thread.
   class AudioSink : public MediaStreamAudioSink {
    public:
     explicit AudioSink(PepperMediaStreamAudioTrackHost* host);
     virtual ~AudioSink();
 
     // Enqueues a free buffer index into |buffers_| which will be used for
     // sending audio samples to plugin.
     // This function is called on the main thread.
     void EnqueueBuffer(int32_t index);
 
+    // This function is called on the main thread.
+    void Configure(int number_of_buffers);

[dcheng, 2014/05/28 15:55:44]

Nit: this should be explicitly sized to int32_t like it used to be

[thembrown, 2014/05/28 17:13:11]

Done.

+
    private:
     // Initializes buffers on the main thread.
-    void InitBuffersOnMainThread(int32_t number_of_buffers,
-                                 int32_t buffer_size);
+    void SetFormatOnMainThread(int bytes_per_second);
+
+    void InitBuffers();
 
     // Send enqueue buffer message on the main thread.
     void SendEnqueueBufferMessageOnMainThread(int32_t index);
 
     // MediaStreamAudioSink overrides:
     // These two functions should be called on the audio thread.
     virtual void OnData(const int16* audio_data,
                         int sample_rate,
                         int number_of_channels,
                         int number_of_frames) OVERRIDE;
@@ skipping 32 matching lines @@
 
     // A queue for free buffer indices.
     std::deque<int32_t> buffers_;
 
     scoped_refptr<base::MessageLoopProxy> main_message_loop_proxy_;
 
     base::ThreadChecker audio_thread_checker_;
 
     base::WeakPtrFactory<AudioSink> weak_factory_;
 
+    // Number of buffers.
+    int32_t number_of_buffers_;
+
+    // Number of bytes per second.
+    int bytes_per_second_;
+
     DISALLOW_COPY_AND_ASSIGN(AudioSink);
   };
 
   virtual ~PepperMediaStreamAudioTrackHost();
 
+  // ResourceMessageHandler overrides:
+  virtual int32_t OnResourceMessageReceived(
+      const IPC::Message& msg,
+      ppapi::host::HostMessageContext* context) OVERRIDE;
+
+  // Message handlers:
+  int32_t OnHostMsgConfigure(
+      ppapi::host::HostMessageContext* context,
+      const ppapi::MediaStreamAudioTrackShared::Attributes& attributes);
+
   // PepperMediaStreamTrackHostBase overrides:
   virtual void OnClose() OVERRIDE;
 
   // MediaStreamBufferManager::Delegate overrides:
   virtual void OnNewBufferEnqueued() OVERRIDE;
 
   // ResourceHost overrides:
   virtual void DidConnectPendingHostToResource() OVERRIDE;
 
   blink::WebMediaStreamTrack track_;
 
   // True if |audio_sink_| has been added to |blink::WebMediaStreamTrack|
   // as a sink.
   bool connected_;
 
   AudioSink audio_sink_;
 
   DISALLOW_COPY_AND_ASSIGN(PepperMediaStreamAudioTrackHost);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_PEPPER_PEPPER_MEDIA_STREAM_AUDIO_TRACK_HOST_H_