Unmute Tab Audio For Desktop Share

media/audio/audio_output_controller.h

 // 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.
 
 #ifndef MEDIA_AUDIO_AUDIO_OUTPUT_CONTROLLER_H_
 #define MEDIA_AUDIO_AUDIO_OUTPUT_CONTROLLER_H_
 
 #include <stdint.h>
+#include <set>
 
 #include "base/atomic_ref_count.h"
 #include "base/callback.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/threading/thread_checker.h"
 #include "base/timer/timer.h"
 #include "build/build_config.h"
 #include "media/audio/audio_io.h"
 #include "media/audio/audio_manager.h"
 #include "media/audio/audio_power_monitor.h"
 #include "media/audio/audio_source_diverter.h"
 #include "media/audio/simple_sources.h"
+#include "media/audio/virtual_audio_sink.h"
 #include "media/base/media_export.h"
 
 // An AudioOutputController controls an AudioOutputStream and provides data
 // to this output stream. It has an important function that it executes
 // audio operations like play, pause, stop, etc. on a separate thread,
 // namely the audio manager thread.
 //
 // All the public methods of AudioOutputController are non-blocking.
 // The actual operations are performed on the audio manager thread.
 //
@@ skipping 18 matching lines @@
 // all functionally equivalent and require a Play() call to continue to the next
 // state.
 //
 // The AudioOutputStream can request data from the AudioOutputController via the
 // AudioSourceCallback interface. AudioOutputController uses the SyncReader
 // passed to it via construction to synchronously fulfill this read request.
 //
 
 namespace media {
 
+class VirtualAudioSink;

[miu, 2016/04/21 00:15:25]

I think you intended to remove this (since it's not used elsewhere in this
header file).

[qiangchen, 2016/04/28 00:00:56]

Done.

+
 class MEDIA_EXPORT AudioOutputController
     : public base::RefCountedThreadSafe<AudioOutputController>,
       public AudioOutputStream::AudioSourceCallback,
       public AudioSourceDiverter,
       NON_EXPORTED_BASE(public AudioManager::AudioDeviceListener)  {
  public:
   // An event handler that receives events from the AudioOutputController. The
   // following methods are called on the audio manager thread.
   class MEDIA_EXPORT EventHandler {
    public:
@@ skipping 99 matching lines @@
   // AudioDeviceListener implementation.  When called AudioOutputController will
   // shutdown the existing |stream_|, transition to the kRecreating state,
   // create a new stream, and then transition back to an equivalent state prior
   // to being called.
   void OnDeviceChange() override;
 
   // AudioSourceDiverter implementation.
   const AudioParameters& GetAudioParameters() override;
   void StartDiverting(AudioOutputStream* to_stream) override;
   void StopDiverting() override;
+  void StartDuplicating(AudioPushSink* sink) override;
+  void StopDuplicating(AudioPushSink* sink) override;
 
   // Accessor for AudioPowerMonitor::ReadCurrentPowerAndClip().  See comments in
   // audio_power_monitor.h for usage.  This may be called on any thread.
   std::pair<float, bool> ReadCurrentPowerAndClip();
 
  protected:
   // Internal state of the source.
   enum State {
     kEmpty,
     kCreated,
@@ skipping 20 matching lines @@
   void DoCreate(bool is_for_device_change);
   void DoPlay();
   void DoPause();
   void DoClose();
   void DoSetVolume(double volume);
   std::string DoGetOutputDeviceId() const;
   void DoSwitchOutputDevice(const std::string& output_device_id);
   void DoReportError();
   void DoStartDiverting(AudioOutputStream* to_stream);
   void DoStopDiverting();
+  void DoStartDuplicating(AudioPushSink* sink);
+  void DoStopDuplicating(AudioPushSink* sink);
 
   // Helper method that stops the physical stream.
   void StopStream();
 
   // Helper method that stops, closes, and NULLs |*stream_|.
-  void DoStopCloseAndClearStream();
+  void DoStopCloseAndClearStream(bool isForDeviceChange);
 
   // Checks if a stream was started successfully but never calls OnMoreData().
   void WedgeCheck();
 
   AudioManager* const audio_manager_;
   const AudioParameters params_;
   EventHandler* const handler_;
 
   // Specifies the device id of the output device to open or empty for the
   // default output device.
   std::string output_device_id_;
 
   AudioOutputStream* stream_;
 
   // When non-NULL, audio is being diverted to this stream.
   AudioOutputStream* diverting_to_stream_;
 
+  // The targets for audio stream to be copied to.
+  std::set<AudioPushSink*> duplicating_targets_;
+
   // The current volume of the audio stream.
   double volume_;
 
   // |state_| may only be used on the audio manager thread.
   State state_;
 
   // SyncReader is used only in low latency mode for synchronous reading.
   SyncReader* const sync_reader_;
 
   // The message loop of audio manager thread that this object runs on.
@@ skipping 15 matching lines @@
   // be accessed while |error_lock_| is held.
   bool ignore_errors_during_stop_close_;
   base::Lock error_lock_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioOutputController);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_AUDIO_AUDIO_OUTPUT_CONTROLLER_H_