summaryrefslogtreecommitdiffstats
path: root/media/audio/audio_manager_base.h
blob: 57b4fe44edb67707401d4b55bd4441dcda9c1dea (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
// 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_MANAGER_BASE_H_
#define MEDIA_AUDIO_AUDIO_MANAGER_BASE_H_

#include <map>
#include <string>
#include <utility>

#include "base/atomic_ref_count.h"
#include "base/compiler_specific.h"
#include "base/memory/scoped_ptr.h"
#include "base/observer_list.h"
#include "base/synchronization/lock.h"
#include "media/audio/audio_manager.h"

#if defined(OS_WIN)
#include "base/win/scoped_com_initializer.h"
#endif

namespace base {
class Thread;
}

namespace media {

class AudioOutputDispatcher;

// AudioManagerBase provides AudioManager functions common for all platforms.
class MEDIA_EXPORT AudioManagerBase : public AudioManager {
 public:
  // Name of the generic "default" device.
  static const char kDefaultDeviceName[];
  // Unique Id of the generic "default" device.
  static const char kDefaultDeviceId[];

  virtual ~AudioManagerBase();

  virtual scoped_refptr<base::MessageLoopProxy> GetMessageLoop() OVERRIDE;

  virtual string16 GetAudioInputDeviceModel() OVERRIDE;

  virtual bool CanShowAudioInputSettings() OVERRIDE;
  virtual void ShowAudioInputSettings() OVERRIDE;

  virtual void GetAudioInputDeviceNames(
      media::AudioDeviceNames* device_names) OVERRIDE;

  virtual AudioOutputStream* MakeAudioOutputStream(
      const AudioParameters& params) OVERRIDE;

  virtual AudioInputStream* MakeAudioInputStream(
      const AudioParameters& params, const std::string& device_id) OVERRIDE;

  virtual AudioOutputStream* MakeAudioOutputStreamProxy(
      const AudioParameters& params) OVERRIDE;

  virtual bool IsRecordingInProcess() OVERRIDE;

  // Called internally by the audio stream when it has been closed.
  virtual void ReleaseOutputStream(AudioOutputStream* stream);
  virtual void ReleaseInputStream(AudioInputStream* stream);

  void IncreaseActiveInputStreamCount();
  void DecreaseActiveInputStreamCount();

  // Creates the output stream for the |AUDIO_PCM_LINEAR| format. The legacy
  // name is also from |AUDIO_PCM_LINEAR|.
  virtual AudioOutputStream* MakeLinearOutputStream(
      const AudioParameters& params) = 0;

  // Creates the output stream for the |AUDIO_PCM_LOW_LATENCY| format.
  virtual AudioOutputStream* MakeLowLatencyOutputStream(
      const AudioParameters& params) = 0;

  // Creates the input stream for the |AUDIO_PCM_LINEAR| format. The legacy
  // name is also from |AUDIO_PCM_LINEAR|.
  virtual AudioInputStream* MakeLinearInputStream(
      const AudioParameters& params, const std::string& device_id) = 0;

  // Creates the input stream for the |AUDIO_PCM_LOW_LATENCY| format.
  virtual AudioInputStream* MakeLowLatencyInputStream(
      const AudioParameters& params, const std::string& device_id) = 0;

  // Returns the preferred hardware audio output parameters for opening output
  // streams in the |AUDIO_PCM_LOW_LATENCY| format.
  // TODO(dalecurtis): Retrieve the |channel_layout| value from hardware instead
  // of accepting the value.
  // TODO(dalecurtis): Each AudioManager should implement their own version, see
  // http://crbug.com/137326
  virtual AudioParameters GetPreferredLowLatencyOutputStreamParameters(
      const AudioParameters& input_params);

  // Listeners will be notified on the AudioManager::GetMessageLoop() loop.
  virtual void AddOutputDeviceChangeListener(
      AudioDeviceListener* listener) OVERRIDE;
  virtual void RemoveOutputDeviceChangeListener(
      AudioDeviceListener* listener) OVERRIDE;

 protected:
  AudioManagerBase();

  // TODO(dalecurtis): This must change to map both input and output parameters
  // to a single dispatcher, otherwise on a device state change we'll just get
  // the exact same invalid dispatcher.
  typedef std::map<std::pair<AudioParameters, AudioParameters>,
                   scoped_refptr<AudioOutputDispatcher> >
      AudioOutputDispatchersMap;

  // Shuts down the audio thread and releases all the audio output dispatchers
  // on the audio thread.  All audio streams should be freed before Shutdown()
  // is called.  This must be called in the destructor of every AudioManagerBase
  // implementation.
  void Shutdown();

  void SetMaxOutputStreamsAllowed(int max) { max_num_output_streams_ = max; }

  // Called by each platform specific AudioManager to notify output state change
  // listeners that a state change has occurred.  Must be called from the audio
  // thread.
  void NotifyAllOutputDeviceChangeListeners();

  // Map of cached AudioOutputDispatcher instances.  Must only be touched
  // from the audio thread (no locking).
  AudioOutputDispatchersMap output_dispatchers_;

 private:
  // Called by Shutdown().
  void ShutdownOnAudioThread();

  // Counts the number of active input streams to find out if something else
  // is currently recording in Chrome.
  base::AtomicRefCount num_active_input_streams_;

  // Max number of open output streams, modified by
  // SetMaxOutputStreamsAllowed().
  int max_num_output_streams_;

  // Max number of open input streams.
  int max_num_input_streams_;

  // Number of currently open output streams.
  int num_output_streams_;

  // Number of currently open input streams.
  int num_input_streams_;

  // Track output state change listeners.
  ObserverList<AudioDeviceListener> output_listeners_;

  // Thread used to interact with audio streams created by this audio manager.
  scoped_ptr<base::Thread> audio_thread_;
  mutable base::Lock audio_thread_lock_;

  // The message loop of the audio thread this object runs on. Used for internal
  // tasks which run on the audio thread even after Shutdown() has been started
  // and GetMessageLoop() starts returning NULL.
  scoped_refptr<base::MessageLoopProxy> message_loop_;

  DISALLOW_COPY_AND_ASSIGN(AudioManagerBase);
};

}  // namespace media

#endif  // MEDIA_AUDIO_AUDIO_MANAGER_BASE_H_