void
AudioSink::AudioLoop()
{
AssertOnAudioThread();
SINK_LOG("AudioLoop started");
if (NS_FAILED(InitializeAudioStream())) {
NS_WARNING("Initializing AudioStream failed.");
mStateMachine->DispatchOnAudioSinkError();
return;
}
while (1) {
{
ReentrantMonitorAutoEnter mon(GetReentrantMonitor());
WaitForAudioToPlay();
if (!IsPlaybackContinuing()) {
break;
}
}
// See if there's a gap in the audio. If there is, push silence into the
// audio hardware, so we can play across the gap.
// Calculate the timestamp of the next chunk of audio in numbers of
// samples.
NS_ASSERTION(AudioQueue().GetSize() > 0, "Should have data to play");
CheckedInt64 sampleTime = UsecsToFrames(AudioQueue().PeekFront()->mTime, mInfo.mRate);
// Calculate the number of frames that have been pushed onto the audio hardware.
CheckedInt64 playedFrames = UsecsToFrames(mStartTime, mInfo.mRate) + mWritten;
CheckedInt64 missingFrames = sampleTime - playedFrames;
if (!missingFrames.isValid() || !sampleTime.isValid()) {
NS_WARNING("Int overflow adding in AudioLoop");
break;
}
if (missingFrames.value() > AUDIO_FUZZ_FRAMES) {
// The next audio chunk begins some time after the end of the last chunk
// we pushed to the audio hardware. We must push silence into the audio
// hardware so that the next audio chunk begins playback at the correct
// time.
missingFrames = std::min<int64_t>(UINT32_MAX, missingFrames.value());
mWritten += PlaySilence(static_cast<uint32_t>(missingFrames.value()));
} else {
mWritten += PlayFromAudioQueue();
}
int64_t endTime = GetEndTime();
if (endTime != -1) {
mOnAudioEndTimeUpdateTask->Dispatch(endTime);
}
}
ReentrantMonitorAutoEnter mon(GetReentrantMonitor());
MOZ_ASSERT(mStopAudioThread || AudioQueue().AtEndOfStream());
if (!mStopAudioThread && mPlaying) {
Drain();
}
SINK_LOG("AudioLoop complete");
Cleanup();
SINK_LOG("AudioLoop exit");
}
bool
DecodedAudioDataSink::PlayAudio()
{
// See if there's a gap in the audio. If there is, push silence into the
// audio hardware, so we can play across the gap.
// Calculate the timestamp of the next chunk of audio in numbers of
// samples.
NS_ASSERTION(AudioQueue().GetSize() > 0, "Should have data to play");
CheckedInt64 sampleTime = UsecsToFrames(AudioQueue().PeekFront()->mTime, mInfo.mRate);
// Calculate the number of frames that have been pushed onto the audio hardware.
CheckedInt64 playedFrames = UsecsToFrames(mStartTime, mInfo.mRate) +
static_cast<int64_t>(mWritten);
CheckedInt64 missingFrames = sampleTime - playedFrames;
if (!missingFrames.isValid() || !sampleTime.isValid()) {
NS_WARNING("Int overflow adding in AudioLoop");
return false;
}
if (missingFrames.value() > AUDIO_FUZZ_FRAMES) {
// The next audio chunk begins some time after the end of the last chunk
// we pushed to the audio hardware. We must push silence into the audio
// hardware so that the next audio chunk begins playback at the correct
// time.
missingFrames = std::min<int64_t>(UINT32_MAX, missingFrames.value());
mWritten += PlaySilence(static_cast<uint32_t>(missingFrames.value()));
} else {
mWritten += PlayFromAudioQueue();
}
return true;
}