Index: media/audio/audio_output_dispatcher.h |
=================================================================== |
--- media/audio/audio_output_dispatcher.h (revision 132979) |
+++ media/audio/audio_output_dispatcher.h (working copy) |
@@ -2,33 +2,26 @@ |
// Use of this source code is governed by a BSD-style license that can be |
// found in the LICENSE file. |
-// AudioOutputDispatcher is a single-threaded class that dispatches creation and |
-// deletion of audio output streams. AudioOutputProxy objects use this class to |
-// allocate and recycle actual audio output streams. When playback is started, |
-// the proxy calls StreamStarted() to get an output stream that it uses to play |
-// audio. When playback is stopped, the proxy returns the stream back to the |
-// dispatcher by calling StreamStopped(). |
+// AudioOutputDispatcher is a single-threaded base class that dispatches |
+// creation and deletion of audio output streams. AudioOutputProxy objects use |
+// this class to allocate and recycle actual audio output streams. When playback |
+// is started, the proxy calls StartStream() to get an output stream that it |
+// uses to play audio. When playback is stopped, the proxy returns the stream |
+// back to the dispatcher by calling StopStream(). |
// |
-// To avoid opening and closing audio devices more frequently than necessary, |
-// each dispatcher has a pool of inactive physical streams. A stream is closed |
-// only if it hasn't been used for a certain period of time (specified via the |
-// constructor). |
-// |
-// AudioManagerBase creates one AudioOutputDispatcher on the audio thread for |
-// each possible set of audio parameters. I.e streams with different parameters |
-// are managed independently. The AudioOutputDispatcher instance is then |
-// deleted on the audio thread when the AudioManager shuts down. |
+// AudioManagerBase creates one specialization of AudioOutputDispatcher on the |
+// audio thread for each possible set of audio parameters. I.e streams with |
+// different parameters are managed independently. The AudioOutputDispatcher |
+// instance is then deleted on the audio thread when the AudioManager shuts |
+// down. |
#ifndef MEDIA_AUDIO_AUDIO_OUTPUT_DISPATCHER_H_ |
#define MEDIA_AUDIO_AUDIO_OUTPUT_DISPATCHER_H_ |
-#include <vector> |
-#include <list> |
- |
#include "base/basictypes.h" |
#include "base/memory/ref_counted.h" |
-#include "base/memory/weak_ptr.h" |
#include "base/timer.h" |
+#include "media/audio/audio_io.h" |
#include "media/audio/audio_manager.h" |
#include "media/audio/audio_parameters.h" |
@@ -36,77 +29,51 @@ |
namespace media { |
-class AudioOutputStream; |
+class AudioOutputProxy; |
class MEDIA_EXPORT AudioOutputDispatcher |
: public base::RefCountedThreadSafe<AudioOutputDispatcher> { |
public: |
- // |close_delay_ms| specifies delay after the stream is paused until |
- // the audio device is closed. |
AudioOutputDispatcher(AudioManager* audio_manager, |
- const AudioParameters& params, |
- base::TimeDelta close_delay); |
- ~AudioOutputDispatcher(); |
+ const AudioParameters& params); |
- // Called by AudioOutputProxy when the stream is closed. Opens a new |
- // physical stream if there are no pending streams in |idle_streams_|. |
+ // Called by AudioOutputProxy to open the stream. |
// Returns false, if it fails to open it. |
- bool StreamOpened(); |
+ virtual bool OpenStream() = 0; |
- // Called by AudioOutputProxy when the stream is started. If there |
- // are pending streams in |idle_streams_| then it returns one of them, |
- // otherwise creates a new one. Returns a physical stream that must |
- // be used, or NULL if it fails to open audio device. Ownership of |
- // the result is passed to the caller. |
- AudioOutputStream* StreamStarted(); |
+ // Called by AudioOutputProxy when the stream is started. |
+ // Uses |callback| to get source data and report errors, if any. |
+ // Does *not* take ownership of this callback. |
+ // Returns true if started successfully, false otherwise. |
+ virtual bool StartStream(AudioOutputStream::AudioSourceCallback* callback, |
+ AudioOutputProxy* stream_proxy) = 0; |
- // Called by AudioOutputProxy when the stream is stopped. Holds the |
- // stream temporarily in |pausing_streams_| and then |stream| is |
- // added to the pool of pending streams (i.e. |idle_streams_|). |
- // Ownership of the |stream| is passed to the dispatcher. |
- void StreamStopped(AudioOutputStream* stream); |
+ // Called by AudioOutputProxy when the stream is stopped. |
+ // Ownership of the |stream_proxy| is passed to the dispatcher. |
+ virtual void StopStream(AudioOutputProxy* stream_proxy) = 0; |
+ |
+ // Called by AudioOutputProxy when the volume is set. |
+ virtual void StreamVolumeSet(AudioOutputProxy* stream_proxy, |
+ double volume) = 0; |
+ |
// Called by AudioOutputProxy when the stream is closed. |
- void StreamClosed(); |
+ virtual void CloseStream(AudioOutputProxy* stream_proxy) = 0; |
// Called on the audio thread when the AudioManager is shutting down. |
- void Shutdown(); |
+ virtual void Shutdown() = 0; |
- private: |
- friend class AudioOutputProxyTest; |
+ protected: |
+ friend class base::RefCountedThreadSafe<AudioOutputDispatcher>; |
+ virtual ~AudioOutputDispatcher(); |
- // Creates a new physical output stream, opens it and pushes to |
- // |idle_streams_|. Returns false if the stream couldn't be created or |
- // opened. |
- bool CreateAndOpenStream(); |
- |
- // A task scheduled by StreamStarted(). Opens a new stream and puts |
- // it in |idle_streams_|. |
- void OpenTask(); |
- |
- // Before a stream is reused, it should sit idle for a bit. This task is |
- // called once that time has elapsed. |
- void StopStreamTask(); |
- |
- // Called by |close_timer_|. Closes all pending stream. |
- void ClosePendingStreams(); |
- |
// A no-reference-held pointer (we don't want circular references) back to the |
// AudioManager that owns this object. |
AudioManager* audio_manager_; |
MessageLoop* message_loop_; |
AudioParameters params_; |
- base::TimeDelta pause_delay_; |
- size_t paused_proxies_; |
- typedef std::list<AudioOutputStream*> AudioOutputStreamList; |
- AudioOutputStreamList idle_streams_; |
- AudioOutputStreamList pausing_streams_; |
- |
- // Used to post delayed tasks to ourselves that we cancel inside Shutdown(). |
- base::WeakPtrFactory<AudioOutputDispatcher> weak_this_; |
- base::DelayTimer<AudioOutputDispatcher> close_timer_; |
- |
+ private: |
DISALLOW_COPY_AND_ASSIGN(AudioOutputDispatcher); |
}; |