content/browser/renderer_host/media/audio_renderer_host.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 // AudioRendererHost serves audio related requests from AudioRenderer which
   6 // lives inside the render process and provide access to audio hardware.
   7 //
   8 // This class is owned by BrowserRenderProcessHost, and instantiated on UI
   9 // thread, but all other operations and method calls happen on IO thread, so we
  10 // need to be extra careful about the lifetime of this object. AudioManager is a
  11 // singleton and created in IO thread, audio output streams are also created in
  12 // the IO thread, so we need to destroy them also in IO thread. After this class
  13 // is created, a task of OnInitialized() is posted on IO thread in which
  14 // singleton of AudioManager is created.
  15 //
  16 // Here's an example of a typical IPC dialog for audio:
  17 //
  18 //   Renderer                     AudioRendererHost
  19 //      |                               |
  20 //      |         CreateStream >        |
  21 //      |     < NotifyStreamCreated     |
  22 //      |                               |
  23 //      |          PlayStream >         |
  24 //      |  < NotifyStreamStateChanged   | kAudioStreamPlaying
  25 //      |                               |
  26 //      |         PauseStream >         |
  27 //      |  < NotifyStreamStateChanged   | kAudioStreamPaused
  28 //      |                               |
  29 //      |          PlayStream >         |
  30 //      |  < NotifyStreamStateChanged   | kAudioStreamPlaying
  31 //      |             ...               |
  32 //      |         CloseStream >         |
  33 //      v                               v
  34
  35 // A SyncSocket pair is used to signal buffer readiness between processes.
  36
  37 #ifndef CONTENT_BROWSER_RENDERER_HOST_MEDIA_AUDIO_RENDERER_HOST_H_
  38 #define CONTENT_BROWSER_RENDERER_HOST_MEDIA_AUDIO_RENDERER_HOST_H_
  39
  40 #include <map>
  41
  42 #include "base/gtest_prod_util.h"
  43 #include "base/memory/ref_counted.h"
  44 #include "base/memory/scoped_ptr.h"
  45 #include "base/process.h"
  46 #include "base/sequenced_task_runner_helpers.h"
  47 #include "base/shared_memory.h"
  48 #include "content/common/content_export.h"
  49 #include "content/public/browser/browser_message_filter.h"
  50 #include "content/public/browser/browser_thread.h"
  51 #include "media/audio/audio_io.h"
  52 #include "media/audio/audio_output_controller.h"
  53 #include "media/audio/simple_sources.h"
  54
  55 namespace media {
  56 class AudioManager;
  57 class AudioParameters;
  58 }
  59
  60 namespace content {
  61
  62 class AudioMirroringManager;
  63 class MediaInternals;
  64 class MediaStreamManager;
  65 class ResourceContext;
  66
  67 class CONTENT_EXPORT AudioRendererHost : public BrowserMessageFilter {
  68  public:
  69   // Called from UI thread from the owner of this object.
  70   AudioRendererHost(int render_process_id,
  71                     media::AudioManager* audio_manager,
  72                     AudioMirroringManager* mirroring_manager,
  73                     MediaInternals* media_internals,
  74                     MediaStreamManager* media_stream_manager);
  75
  76   // BrowserMessageFilter implementation.
  77   virtual void OnChannelClosing() OVERRIDE;
  78   virtual void OnDestruct() const OVERRIDE;
  79   virtual bool OnMessageReceived(const IPC::Message& message,
  80                                  bool* message_was_ok) OVERRIDE;
  81
  82  private:
  83   friend class AudioRendererHostTest;
  84   friend class BrowserThread;
  85   friend class base::DeleteHelper<AudioRendererHost>;
  86   friend class MockAudioRendererHost;
  87   FRIEND_TEST_ALL_PREFIXES(AudioRendererHostTest, CreateMockStream);
  88   FRIEND_TEST_ALL_PREFIXES(AudioRendererHostTest, MockStreamDataConversation);
  89
  90   class AudioEntry;
  91   typedef std::map<int, AudioEntry*> AudioEntryMap;
  92
  93   virtual ~AudioRendererHost();
  94
  95   // Methods called on IO thread ----------------------------------------------
  96
  97   // Audio related IPC message handlers.
  98
  99   // Creates an audio output stream with the specified format whose data is
 100   // produced by an entity in the render view referenced by |render_view_id|.
 101   // |session_id| is used for unified IO to find out which input device to be
 102   // opened for the stream. For clients that do not use unified IO,
 103   // |session_id| will be ignored.
 104   // Upon success/failure, the peer is notified via the NotifyStreamCreated
 105   // message.
 106   void OnCreateStream(int stream_id,
 107                       int render_view_id,
 108                       int session_id,
 109                       const media::AudioParameters& params);
 110
 111   // Play the audio stream referenced by |stream_id|.
 112   void OnPlayStream(int stream_id);
 113
 114   // Pause the audio stream referenced by |stream_id|.
 115   void OnPauseStream(int stream_id);
 116
 117   // Close the audio stream referenced by |stream_id|.
 118   void OnCloseStream(int stream_id);
 119
 120   // Set the volume of the audio stream referenced by |stream_id|.
 121   void OnSetVolume(int stream_id, double volume);
 122
 123   // Complete the process of creating an audio stream. This will set up the
 124   // shared memory or shared socket in low latency mode and send the
 125   // NotifyStreamCreated message to the peer.
 126   void DoCompleteCreation(AudioEntry* entry);
 127
 128   // Propagate audible signal to MediaObserver.
 129   void DoNotifyAudibleState(AudioEntry* entry, bool is_audible);
 130
 131   // Send an error message to the renderer.
 132   void SendErrorMessage(int stream_id);
 133
 134   // Delete an audio entry, notifying observers first.  This is called by
 135   // AudioOutputController after it has closed.
 136   void DeleteEntry(scoped_ptr<AudioEntry> entry);
 137
 138   // Send an error message to the renderer, then close the stream.
 139   void ReportErrorAndClose(int stream_id);
 140
 141   // A helper method to look up a AudioEntry identified by |stream_id|.
 142   // Returns NULL if not found.
 143   AudioEntry* LookupById(int stream_id);
 144
 145   // ID of the RenderProcessHost that owns this instance.
 146   const int render_process_id_;
 147
 148   media::AudioManager* const audio_manager_;
 149   AudioMirroringManager* const mirroring_manager_;
 150   MediaInternals* const media_internals_;
 151
 152   // Used to access to AudioInputDeviceManager.
 153   MediaStreamManager* media_stream_manager_;
 154
 155   // A map of stream IDs to audio sources.
 156   AudioEntryMap audio_entries_;
 157
 158   DISALLOW_COPY_AND_ASSIGN(AudioRendererHost);
 159 };
 160
 161 }  // namespace content
 162
 163 #endif  // CONTENT_BROWSER_RENDERER_HOST_MEDIA_AUDIO_RENDERER_HOST_H_