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 MEDIA_AUDIO_AUDIO_MANAGER_BASE_H_ 6 #define MEDIA_AUDIO_AUDIO_MANAGER_BASE_H_ 7 8 #include <string> 9 #include <utility> 10 11 #include "base/compiler_specific.h" 12 #include "base/memory/scoped_ptr.h" 13 #include "base/memory/scoped_vector.h" 14 #include "base/observer_list.h" 15 #include "base/synchronization/lock.h" 16 #include "media/audio/audio_manager.h" 17 18 #include "media/audio/audio_output_dispatcher.h" 19 20 #if defined(OS_WIN) 21 #include "base/win/scoped_com_initializer.h" 22 #endif 23 24 namespace base { 25 class Thread; 26 } 27 28 namespace media { 29 30 class AudioOutputDispatcher; 31 32 // AudioManagerBase provides AudioManager functions common for all platforms. 33 class MEDIA_EXPORT AudioManagerBase : public AudioManager { 34 public: 35 // Name of the generic "default" device. 36 static const char kDefaultDeviceName[]; 37 // Unique Id of the generic "default" device. 38 static const char kDefaultDeviceId[]; 39 40 virtual ~AudioManagerBase(); 41 42 virtual scoped_refptr<base::MessageLoopProxy> GetMessageLoop() OVERRIDE; 43 virtual scoped_refptr<base::MessageLoopProxy> GetWorkerLoop() OVERRIDE; 44 45 virtual string16 GetAudioInputDeviceModel() OVERRIDE; 46 47 virtual void ShowAudioInputSettings() OVERRIDE; 48 49 virtual void GetAudioInputDeviceNames( 50 media::AudioDeviceNames* device_names) OVERRIDE; 51 52 virtual AudioOutputStream* MakeAudioOutputStream( 53 const AudioParameters& params, 54 const std::string& input_device_id) OVERRIDE; 55 56 virtual AudioInputStream* MakeAudioInputStream( 57 const AudioParameters& params, const std::string& device_id) OVERRIDE; 58 59 virtual AudioOutputStream* MakeAudioOutputStreamProxy( 60 const AudioParameters& params, 61 const std::string& input_device_id) OVERRIDE; 62 63 // Called internally by the audio stream when it has been closed. 64 virtual void ReleaseOutputStream(AudioOutputStream* stream); 65 virtual void ReleaseInputStream(AudioInputStream* stream); 66 67 // Creates the output stream for the |AUDIO_PCM_LINEAR| format. The legacy 68 // name is also from |AUDIO_PCM_LINEAR|. 69 virtual AudioOutputStream* MakeLinearOutputStream( 70 const AudioParameters& params) = 0; 71 72 // Creates the output stream for the |AUDIO_PCM_LOW_LATENCY| format. 73 // |input_device_id| is used by unified IO to open the correct input device. 74 virtual AudioOutputStream* MakeLowLatencyOutputStream( 75 const AudioParameters& params, const std::string& input_device_id) = 0; 76 77 // Creates the input stream for the |AUDIO_PCM_LINEAR| format. The legacy 78 // name is also from |AUDIO_PCM_LINEAR|. 79 virtual AudioInputStream* MakeLinearInputStream( 80 const AudioParameters& params, const std::string& device_id) = 0; 81 82 // Creates the input stream for the |AUDIO_PCM_LOW_LATENCY| format. 83 virtual AudioInputStream* MakeLowLatencyInputStream( 84 const AudioParameters& params, const std::string& device_id) = 0; 85 86 // Listeners will be notified on the AudioManager::GetMessageLoop() loop. 87 virtual void AddOutputDeviceChangeListener( 88 AudioDeviceListener* listener) OVERRIDE; 89 virtual void RemoveOutputDeviceChangeListener( 90 AudioDeviceListener* listener) OVERRIDE; 91 92 virtual AudioParameters GetDefaultOutputStreamParameters() OVERRIDE; 93 virtual AudioParameters GetInputStreamParameters( 94 const std::string& device_id) OVERRIDE; 95 96 protected: 97 AudioManagerBase(); 98 99 100 // Shuts down the audio thread and releases all the audio output dispatchers 101 // on the audio thread. All audio streams should be freed before Shutdown() 102 // is called. This must be called in the destructor of every AudioManagerBase 103 // implementation. 104 void Shutdown(); 105 106 void SetMaxOutputStreamsAllowed(int max) { max_num_output_streams_ = max; } 107 108 // Called by each platform specific AudioManager to notify output state change 109 // listeners that a state change has occurred. Must be called from the audio 110 // thread. 111 void NotifyAllOutputDeviceChangeListeners(); 112 113 // Returns the preferred hardware audio output parameters for opening output 114 // streams. If the users inject a valid |input_params|, each AudioManager 115 // will decide if they should return the values from |input_params| or the 116 // default hardware values. If the |input_params| is invalid, it will return 117 // the default hardware audio parameters. 118 virtual AudioParameters GetPreferredOutputStreamParameters( 119 const AudioParameters& input_params) = 0; 120 121 // Get number of input or output streams. 122 int input_stream_count() { return num_input_streams_; } 123 int output_stream_count() { return num_output_streams_; } 124 125 private: 126 struct DispatcherParams; 127 typedef ScopedVector<DispatcherParams> AudioOutputDispatchers; 128 129 class CompareByParams; 130 131 // Called by Shutdown(). 132 void ShutdownOnAudioThread(); 133 134 // Max number of open output streams, modified by 135 // SetMaxOutputStreamsAllowed(). 136 int max_num_output_streams_; 137 138 // Max number of open input streams. 139 int max_num_input_streams_; 140 141 // Number of currently open output streams. 142 int num_output_streams_; 143 144 // Number of currently open input streams. 145 int num_input_streams_; 146 147 // Track output state change listeners. 148 ObserverList<AudioDeviceListener> output_listeners_; 149 150 // Thread used to interact with audio streams created by this audio manager. 151 scoped_ptr<base::Thread> audio_thread_; 152 mutable base::Lock audio_thread_lock_; 153 154 // The message loop of the audio thread this object runs on. Used for internal 155 // tasks which run on the audio thread even after Shutdown() has been started 156 // and GetMessageLoop() starts returning NULL. 157 scoped_refptr<base::MessageLoopProxy> message_loop_; 158 159 // Map of cached AudioOutputDispatcher instances. Must only be touched 160 // from the audio thread (no locking). 161 AudioOutputDispatchers output_dispatchers_; 162 163 DISALLOW_COPY_AND_ASSIGN(AudioManagerBase); 164 }; 165 166 } // namespace media 167 168 #endif // MEDIA_AUDIO_AUDIO_MANAGER_BASE_H_ 169
