Stop playing/recording when not needed.

components/copresence/mediums/audio/audio_recorder.h

 // Copyright 2014 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 COMPONENTS_COPRESENCE_MEDIUMS_AUDIO_AUDIO_RECORDER_
-#define COMPONENTS_COPRESENCE_MEDIUMS_AUDIO_AUDIO_RECORDER_
+#ifndef COMPONENTS_COPRESENCE_MEDIUMS_AUDIO_AUDIO_RECORDER_H_
+#define COMPONENTS_COPRESENCE_MEDIUMS_AUDIO_AUDIO_RECORDER_H_
 
 #include <string>
 
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/memory/scoped_ptr.h"
 #include "media/audio/audio_io.h"
 #include "media/audio/audio_parameters.h"
 #include "media/base/audio_converter.h"
 
 namespace base {
 class MessageLoop;
 }
 
 namespace media {
 class AudioBus;
 }
 
 namespace copresence {
 
 // The AudioRecorder class will record audio until told to stop.
 class AudioRecorder : public media::AudioInputStream::AudioInputCallback,
                       public media::AudioConverter::InputCallback {
  public:
   typedef base::Callback<void(const std::string&)> DecodeSamplesCallback;
 
   explicit AudioRecorder(const DecodeSamplesCallback& decode_callback);
 
   // Initializes the object. Do not use this object before calling this method.
-  void Initialize();
+  virtual void Initialize();
 
-  void Record();
-  void Stop();
+  virtual void Record();
+  virtual void Stop();
 
   // Cleans up and deletes this object. Do not use object after this call.
-  void Finalize();
+  virtual void Finalize();
+
+  bool IsRecording();
 
   // Takes ownership of the stream.
   void set_input_stream_for_testing(
       media::AudioInputStream* input_stream_for_testing) {
     input_stream_for_testing_.reset(input_stream_for_testing);
   }
 
   // Takes ownership of the params.
   void set_params_for_testing(media::AudioParameters* params_for_testing) {
     params_for_testing_.reset(params_for_testing);
   }
 
+ protected:
+  virtual ~AudioRecorder();
+  void set_is_recording(bool is_recording) { is_recording_ = is_recording; }
+
  private:
   friend class AudioRecorderTest;
   FRIEND_TEST_ALL_PREFIXES(AudioRecorderTest, BasicRecordAndStop);
   FRIEND_TEST_ALL_PREFIXES(AudioRecorderTest, OutOfOrderRecordAndStopMultiple);
 
-  virtual ~AudioRecorder();
-
   // Methods to do our various operations; all of these need to be run on the
   // audio thread.
   void InitializeOnAudioThread();
   void RecordOnAudioThread();
   void StopOnAudioThread();
   void StopAndCloseOnAudioThread();
   void FinalizeOnAudioThread();
 
   // AudioInputStream::AudioInputCallback overrides:
   // Called by the audio recorder when a full packet of audio data is
   // available. This is called from a special audio thread and the
   // implementation should return as soon as possible.
   virtual void OnData(media::AudioInputStream* stream,
                       const media::AudioBus* source,
                       uint32 hardware_delay_bytes,
                       double volume) OVERRIDE;
   virtual void OnError(media::AudioInputStream* stream) OVERRIDE;
 
   // AudioConverter::InputCallback overrides:
   virtual double ProvideInput(media::AudioBus* dest,
                               base::TimeDelta buffer_delay) OVERRIDE;
 
   // Flushes the audio loop, making sure that any queued operations are
   // performed.
   void FlushAudioLoopForTesting();
 
+  bool is_recording_;
+
   media::AudioInputStream* stream_;
-  bool is_recording_;
   DecodeSamplesCallback decode_callback_;
 
   // ProvideInput will use this buffer as its source.
   const media::AudioBus* temp_conversion_buffer_;
 
   // Outside of the ctor/Initialize method, only access the next variables on
   // the recording thread.
   scoped_ptr<media::AudioBus> buffer_;
   int total_buffer_frames_;
   int buffer_frame_index_;
 
   scoped_ptr<media::AudioConverter> converter_;
 
   scoped_ptr<media::AudioInputStream> input_stream_for_testing_;
   scoped_ptr<media::AudioParameters> params_for_testing_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioRecorder);
 };
 
 }  // namespace copresence
 
-#endif  // COMPONENTS_COPRESENCE_MEDIUMS_AUDIO_AUDIO_RECORDER_
+#endif  // COMPONENTS_COPRESENCE_MEDIUMS_AUDIO_AUDIO_RECORDER_H_