diff options
| -rw-r--r-- | media/audio/audio_output_controller.cc | 70 | ||||
| -rw-r--r-- | media/audio/audio_output_controller.h | 45 | ||||
| -rw-r--r-- | media/audio/audio_output_controller_unittest.cc | 45 |
3 files changed, 120 insertions, 40 deletions
diff --git a/media/audio/audio_output_controller.cc b/media/audio/audio_output_controller.cc index 7118eaa..cd57bed 100644 --- a/media/audio/audio_output_controller.cc +++ b/media/audio/audio_output_controller.cc @@ -176,9 +176,10 @@ void AudioOutputController::DoPlay() { // We can start from created or paused state. if (state_ != kCreated && state_ != kPaused) return; - state_ = kPlaying; if (LowLatencyMode()) { + state_ = kStarting; + // Ask for first packet. sync_reader_->UpdatePendingBytes(0); @@ -197,13 +198,20 @@ void AudioOutputController::DoPlay() { void AudioOutputController::PollAndStartIfDataReady() { DCHECK_EQ(message_loop_, MessageLoop::current()); - // Being paranoic: do nothing if we were stopped/paused - // after DoPlay() but before DoStartStream(). - if (state_ != kPlaying) + // Being paranoic: do nothing if state unexpectedly changed. + if ((state_ != kStarting) && (state_ != kPausedWhenStarting)) return; - if (--number_polling_attempts_left_ == 0 || sync_reader_->DataReady()) { + bool pausing = (state_ == kPausedWhenStarting); + // If we are ready to start the stream, start it. + // Of course we may have to stop it immediately... + if (--number_polling_attempts_left_ == 0 || + pausing || + sync_reader_->DataReady()) { StartStream(); + if (pausing) { + DoPause(); + } } else { message_loop_->PostDelayedTask( FROM_HERE, @@ -214,6 +222,7 @@ void AudioOutputController::PollAndStartIfDataReady() { void AudioOutputController::StartStream() { DCHECK_EQ(message_loop_, MessageLoop::current()); + state_ = kPlaying; // We start the AudioOutputStream lazily. stream_->Start(this); @@ -225,22 +234,32 @@ void AudioOutputController::StartStream() { void AudioOutputController::DoPause() { DCHECK_EQ(message_loop_, MessageLoop::current()); - // We can pause from started state. - if (state_ != kPlaying) - return; - state_ = kPaused; + switch (state_) { + case kStarting: + // We were asked to pause while starting. There is delayed task that will + // try starting playback, and there is no way to remove that task from the + // queue. If we stop now that task will be executed anyway. + // Delay pausing, let delayed task to do pause after it start playback. + state_ = kPausedWhenStarting; + break; + case kPlaying: + state_ = kPaused; + + // Then we stop the audio device. This is not the perfect solution + // because it discards all the internal buffer in the audio device. + // TODO(hclam): Actually pause the audio device. + stream_->Stop(); - // Then we stop the audio device. This is not the perfect solution because - // it discards all the internal buffer in the audio device. - // TODO(hclam): Actually pause the audio device. - stream_->Stop(); + if (LowLatencyMode()) { + // Send a special pause mark to the low-latency audio thread. + sync_reader_->UpdatePendingBytes(kPauseMark); + } - if (LowLatencyMode()) { - // Send a special pause mark to the low-latency audio thread. - sync_reader_->UpdatePendingBytes(kPauseMark); + handler_->OnPaused(this); + break; + default: + return; } - - handler_->OnPaused(this); } void AudioOutputController::DoFlush() { @@ -287,10 +306,17 @@ void AudioOutputController::DoSetVolume(double volume) { // right away but when the stream is created we'll set the volume. volume_ = volume; - if (state_ != kPlaying && state_ != kPaused && state_ != kCreated) - return; - - stream_->SetVolume(volume_); + switch (state_) { + case kCreated: + case kStarting: + case kPausedWhenStarting: + case kPlaying: + case kPaused: + stream_->SetVolume(volume_); + break; + default: + return; + } } void AudioOutputController::DoReportError(int code) { diff --git a/media/audio/audio_output_controller.h b/media/audio/audio_output_controller.h index 2c2246b..e359d27c 100644 --- a/media/audio/audio_output_controller.h +++ b/media/audio/audio_output_controller.h @@ -25,15 +25,21 @@ class MessageLoop; // All the public methods of AudioOutputController are non-blocking except // close, the actual operations are performed on the audio controller thread. // -// Here is a state diagram for the AudioOutputController: +// Here is a state diagram for the AudioOutputController for default low +// latency mode; in normal latency mode there is no "starting" or "paused when +// starting" states, "created" immediately switches to "playing": // -// .----> [ Closed / Error ] <------. -// | ^ | -// | | | -// [ Created ] --> [ Playing ] --> [ Paused ] -// ^ ^ | -// | | | -// *[ Empty ] `-----------------' +// .-----------------------> [ Closed / Error ] <------. +// | ^ | +// | | | +// [ Created ] --> [ Starting ] --> [ Playing ] --> [ Paused ] +// ^ | ^ | ^ +// | | | | | +// | | `----------------' | +// | V | +// | [ PausedWhenStarting ] ------------------------' +// | +// *[ Empty ] // // * Initial state // @@ -55,16 +61,6 @@ class MEDIA_EXPORT AudioOutputController : public base::RefCountedThreadSafe<AudioOutputController>, public AudioOutputStream::AudioSourceCallback { public: - // Internal state of the source. - enum State { - kEmpty, - kCreated, - kPlaying, - kPaused, - kClosed, - kError, - }; - // Value sent by the controller to the renderer in low-latency mode // indicating that the stream is paused. static const int kPauseMark; @@ -169,6 +165,19 @@ class MEDIA_EXPORT AudioOutputController uint32 max_size, AudioBuffersState buffers_state); virtual void OnError(AudioOutputStream* stream, int code); + protected: + // Internal state of the source. + enum State { + kEmpty, + kCreated, + kPlaying, + kStarting, + kPausedWhenStarting, + kPaused, + kClosed, + kError, + }; + private: // We are polling sync reader if data became available. static const int kPollNumAttempts; diff --git a/media/audio/audio_output_controller_unittest.cc b/media/audio/audio_output_controller_unittest.cc index 6a58bb5..74e0e68 100644 --- a/media/audio/audio_output_controller_unittest.cc +++ b/media/audio/audio_output_controller_unittest.cc @@ -258,6 +258,51 @@ TEST(AudioOutputControllerTest, PlayPauseClose) { CloseAudioController(controller); } +TEST(AudioOutputControllerTest, PlayPauseCloseLowLatency) { + if (!HasAudioOutputDevices() || IsRunningHeadless()) + return; + + MockAudioOutputControllerEventHandler event_handler; + base::WaitableEvent event(false, false); + base::WaitableEvent pause_event(false, false); + + // If OnCreated is called then signal the event. + EXPECT_CALL(event_handler, OnCreated(NotNull())) + .WillOnce(InvokeWithoutArgs(&event, &base::WaitableEvent::Signal)); + + // OnPlaying() will be called only once. + EXPECT_CALL(event_handler, OnPlaying(NotNull())); + + MockAudioOutputControllerSyncReader sync_reader; + EXPECT_CALL(sync_reader, UpdatePendingBytes(_)) + .Times(AtLeast(2)); + EXPECT_CALL(sync_reader, Read(_, kHardwareBufferSize)) + .WillRepeatedly(DoAll(SignalEvent(&event), + Return(4))); + EXPECT_CALL(event_handler, OnPaused(NotNull())) + .WillOnce(InvokeWithoutArgs(&pause_event, &base::WaitableEvent::Signal)); + EXPECT_CALL(sync_reader, Close()); + + AudioParameters params(AudioParameters::AUDIO_PCM_LINEAR, kChannelLayout, + kSampleRate, kBitsPerSample, kSamplesPerPacket); + scoped_refptr<AudioOutputController> controller = + AudioOutputController::CreateLowLatency(&event_handler, + params, + &sync_reader); + ASSERT_TRUE(controller.get()); + + // Wait for OnCreated() to be called. + event.Wait(); + + ASSERT_FALSE(pause_event.IsSignaled()); + controller->Play(); + controller->Pause(); + pause_event.Wait(); + + // Now stop the controller. + CloseAudioController(controller); +} + TEST(AudioOutputControllerTest, PlayPausePlay) { if (!HasAudioOutputDevices() || IsRunningHeadless()) return; |