audio_renderer_host.h revision c2e0dbddbe15c98d52c4786dac06cb8952a8ae6d 
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
55namespace media {
56class AudioManager;
57class AudioParameters;
58}
59
60namespace content {
61
62class AudioMirroringManager;
63class MediaInternals;
64class ResourceContext;
65
66class CONTENT_EXPORT AudioRendererHost : public BrowserMessageFilter {
67 public:
68  // Called from UI thread from the owner of this object.
69  AudioRendererHost(int render_process_id,
70                    media::AudioManager* audio_manager,
71                    AudioMirroringManager* mirroring_manager,
72                    MediaInternals* media_internals);
73
74  // BrowserMessageFilter implementation.
75  virtual void OnChannelClosing() OVERRIDE;
76  virtual void OnDestruct() const OVERRIDE;
77  virtual bool OnMessageReceived(const IPC::Message& message,
78                                 bool* message_was_ok) OVERRIDE;
79
80 private:
81  friend class AudioRendererHostTest;
82  friend class BrowserThread;
83  friend class base::DeleteHelper<AudioRendererHost>;
84  friend class MockAudioRendererHost;
85  FRIEND_TEST_ALL_PREFIXES(AudioRendererHostTest, CreateMockStream);
86  FRIEND_TEST_ALL_PREFIXES(AudioRendererHostTest, MockStreamDataConversation);
87
88  class AudioEntry;
89  typedef std::map<int, AudioEntry*> AudioEntryMap;
90
91  virtual ~AudioRendererHost();
92
93  // Methods called on IO thread ----------------------------------------------
94
95  // Audio related IPC message handlers.
96
97  // Creates an audio output stream with the specified format whose data is
98  // produced by an entity in the render view referenced by |render_view_id|.
99  // Upon success/failure, the peer is notified via the NotifyStreamCreated
100  // message.
101  void OnCreateStream(int stream_id,
102                      int render_view_id,
103                      const media::AudioParameters& params);
104
105  // Play the audio stream referenced by |stream_id|.
106  void OnPlayStream(int stream_id);
107
108  // Pause the audio stream referenced by |stream_id|.
109  void OnPauseStream(int stream_id);
110
111  // Close the audio stream referenced by |stream_id|.
112  void OnCloseStream(int stream_id);
113
114  // Set the volume of the audio stream referenced by |stream_id|.
115  void OnSetVolume(int stream_id, double volume);
116
117  // Complete the process of creating an audio stream. This will set up the
118  // shared memory or shared socket in low latency mode and send the
119  // NotifyStreamCreated message to the peer.
120  void DoCompleteCreation(AudioEntry* entry);
121
122  // Propagate audible signal to MediaObserver.
123  void DoNotifyAudibleState(AudioEntry* entry, bool is_audible);
124
125  // Send an error message to the renderer.
126  void SendErrorMessage(int stream_id);
127
128  // Delete an audio entry, notifying observers first.  This is called by
129  // AudioOutputController after it has closed.
130  void DeleteEntry(scoped_ptr<AudioEntry> entry);
131
132  // Send an error message to the renderer, then close the stream.
133  void ReportErrorAndClose(int stream_id);
134
135  // A helper method to look up a AudioEntry identified by |stream_id|.
136  // Returns NULL if not found.
137  AudioEntry* LookupById(int stream_id);
138
139  // ID of the RenderProcessHost that owns this instance.
140  const int render_process_id_;
141
142  media::AudioManager* const audio_manager_;
143  AudioMirroringManager* const mirroring_manager_;
144  MediaInternals* const media_internals_;
145
146  // A map of stream IDs to audio sources.
147  AudioEntryMap audio_entries_;
148
149  DISALLOW_COPY_AND_ASSIGN(AudioRendererHost);
150};
151
152}  // namespace content
153
154#endif  // CONTENT_BROWSER_RENDERER_HOST_MEDIA_AUDIO_RENDERER_HOST_H_
155