1 // Copyright 2013 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_LOGGING_H_ 6 #define MEDIA_AUDIO_AUDIO_LOGGING_H_ 7 8 #include <string> 9 10 #include "base/memory/scoped_ptr.h" 11 12 namespace media { 13 class AudioParameters; 14 15 // AudioLog logs state information about an active audio component. Each method 16 // takes a |component_id| along with method specific information. Its methods 17 // are safe to call from any thread. 18 class AudioLog { 19 public: 20 virtual ~AudioLog() {} 21 22 // Called when an audio component is created. |params| are the parameters of 23 // the created stream. |device_id| is the id of the audio device opened by 24 // the created stream. 25 virtual void OnCreated(int component_id, 26 const media::AudioParameters& params, 27 const std::string& device_id) = 0; 28 29 // Called when an audio component is started, generally this is synonymous 30 // with "playing." 31 virtual void OnStarted(int component_id) = 0; 32 33 // Called when an audio component is stopped, generally this is synonymous 34 // with "paused." 35 virtual void OnStopped(int component_id) = 0; 36 37 // Called when an audio component is closed, generally this is synonymous 38 // with "deleted." 39 virtual void OnClosed(int component_id) = 0; 40 41 // Called when an audio component encounters an error. 42 virtual void OnError(int component_id) = 0; 43 44 // Called when an audio component changes volume. |volume| is the new volume. 45 virtual void OnSetVolume(int component_id, double volume) = 0; 46 }; 47 48 // AudioLogFactory dispenses AudioLog instances to owning classes for tracking 49 // AudioComponent behavior. All AudioComponents have the concept of an owning 50 // class: 51 // 52 // - AudioInputRendererHost for AudioInputController 53 // - AudioRendererHost for AudioOutputController 54 // - AudioOutputDispatcherImpl for AudioOutputStream 55 // 56 // Each of these owning classes may own multiple instances of each component, as 57 // such each AudioLog supports logging for multiple instances. 58 class AudioLogFactory { 59 public: 60 enum AudioComponent { 61 // Input controllers have a 1:1 mapping with streams, so there's no need to 62 // track both controllers and streams. 63 AUDIO_INPUT_CONTROLLER, 64 // Output controllers may or may not be backed by an active stream, so we 65 // need to track both controllers and streams. 66 AUDIO_OUTPUT_CONTROLLER, 67 AUDIO_OUTPUT_STREAM, 68 AUDIO_COMPONENT_MAX 69 }; 70 71 // Create a new AudioLog object for tracking the behavior for one or more 72 // instances of the given component. Each instance of an "owning" class must 73 // create its own AudioLog. 74 virtual scoped_ptr<AudioLog> CreateAudioLog(AudioComponent component) = 0; 75 76 protected: 77 virtual ~AudioLogFactory() {} 78 }; 79 80 } // namespace media 81 82 #endif // MEDIA_AUDIO_AUDIO_LOGGING_H_ 83
