1 // Copyright (c) 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_FAKE_AUDIO_CONSUMER_H_ 6 #define MEDIA_AUDIO_FAKE_AUDIO_CONSUMER_H_ 7 8 #include "base/callback_forward.h" 9 #include "base/memory/ref_counted.h" 10 #include "media/base/media_export.h" 11 12 namespace base { 13 class SingleThreadTaskRunner; 14 } 15 16 namespace media { 17 class AudioBus; 18 class AudioParameters; 19 20 // A fake audio consumer. Using a provided message loop, FakeAudioConsumer will 21 // simulate a real time consumer of audio data. 22 class MEDIA_EXPORT FakeAudioConsumer { 23 public: 24 // |worker_task_runner| is the task runner on which the ReadCB provided to 25 // Start() will be executed on. This may or may not be the be for the same 26 // thread that invokes the Start/Stop methods. 27 // |params| is used to determine the frequency of callbacks. 28 FakeAudioConsumer( 29 const scoped_refptr<base::SingleThreadTaskRunner>& worker_task_runner, 30 const AudioParameters& params); 31 ~FakeAudioConsumer(); 32 33 // Start executing |read_cb| at a regular intervals. Stop() must be called by 34 // the same thread before destroying FakeAudioConsumer. 35 typedef base::Callback<void(AudioBus* audio_bus)> ReadCB; 36 void Start(const ReadCB& read_cb); 37 38 // Stop executing the ReadCB provided to Start(). Blocks until the worker 39 // loop is not inside a ReadCB invocation. Safe to call multiple times. Must 40 // be called on the same thread that called Start(). 41 void Stop(); 42 43 private: 44 // All state and implementation is kept within this ref-counted class because 45 // cancellation of posted tasks must happen on the worker thread some time 46 // after the call to Stop() (on the main thread) returns. 47 class Worker; 48 const scoped_refptr<Worker> worker_; 49 50 DISALLOW_COPY_AND_ASSIGN(FakeAudioConsumer); 51 }; 52 53 } // namespace media 54 55 #endif // MEDIA_AUDIO_FAKE_AUDIO_CONSUMER_H_ 56
