content/renderer/pepper/pepper_platform_audio_output.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CONTENT_RENDERER_PEPPER_PEPPER_PLATFORM_AUDIO_OUTPUT_H_
   6 #define CONTENT_RENDERER_PEPPER_PEPPER_PLATFORM_AUDIO_OUTPUT_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/memory/ref_counted.h"
  10 #include "base/memory/scoped_ptr.h"
  11 #include "media/audio/audio_output_ipc.h"
  12
  13 namespace media {
  14 class AudioParameters;
  15 }
  16
  17 namespace base {
  18 class SingleThreadTaskRunner;
  19 }
  20
  21 namespace content {
  22 class AudioHelper;
  23
  24 class PepperPlatformAudioOutput
  25     : public media::AudioOutputIPCDelegate,
  26       public base::RefCountedThreadSafe<PepperPlatformAudioOutput> {
  27  public:
  28   // Factory function, returns NULL on failure. StreamCreated() will be called
  29   // when the stream is created.
  30   static PepperPlatformAudioOutput* Create(int sample_rate,
  31                                            int frames_per_buffer,
  32                                            int source_render_frame_id,
  33                                            AudioHelper* client);
  34
  35   // The following three methods are all called on main thread.
  36
  37   // Starts the playback. Returns false on error or if called before the
  38   // stream is created or after the stream is closed.
  39   bool StartPlayback();
  40
  41   // Stops the playback. Returns false on error or if called before the stream
  42   // is created or after the stream is closed.
  43   bool StopPlayback();
  44
  45   // Closes the stream. Make sure to call this before the object is
  46   // destructed.
  47   void ShutDown();
  48
  49   // media::AudioOutputIPCDelegate implementation.
  50   void OnStateChanged(media::AudioOutputIPCDelegateState state) override;
  51   void OnStreamCreated(base::SharedMemoryHandle handle,
  52                        base::SyncSocket::Handle socket_handle,
  53                        int length) override;
  54   void OnOutputDeviceSwitched(int request_id,
  55                               media::SwitchOutputDeviceResult result) override;
  56   void OnIPCClosed() override;
  57
  58  protected:
  59   ~PepperPlatformAudioOutput() override;
  60
  61  private:
  62   friend class base::RefCountedThreadSafe<PepperPlatformAudioOutput>;
  63
  64   PepperPlatformAudioOutput();
  65
  66   bool Initialize(int sample_rate,
  67                   int frames_per_buffer,
  68                   int source_render_frame_id,
  69                   AudioHelper* client);
  70
  71   // I/O thread backends to above functions.
  72   void InitializeOnIOThread(const media::AudioParameters& params);
  73   void StartPlaybackOnIOThread();
  74   void StopPlaybackOnIOThread();
  75   void ShutDownOnIOThread();
  76
  77   // The client to notify when the stream is created. THIS MUST ONLY BE
  78   // ACCESSED ON THE MAIN THREAD.
  79   AudioHelper* client_;
  80
  81   // Used to send/receive IPC. THIS MUST ONLY BE ACCESSED ON THE
  82   // I/O thread except to send messages and get the message loop.
  83   scoped_ptr<media::AudioOutputIPC> ipc_;
  84
  85   scoped_refptr<base::SingleThreadTaskRunner> main_task_runner_;
  86   scoped_refptr<base::SingleThreadTaskRunner> io_task_runner_;
  87
  88   DISALLOW_COPY_AND_ASSIGN(PepperPlatformAudioOutput);
  89 };
  90
  91 }  // namespace content
  92
  93 #endif  // CONTENT_RENDERER_PEPPER_PEPPER_PLATFORM_AUDIO_OUTPUT_H_