public static void poll(ReadOnlySpan <pollfd> waitHandles, out eDecoderBits decoderBits, out eAudioBits audio, out bool seekRequest, out bool shutdownRequest)
{
LibC.poll(waitHandles);
decoderBits = (eDecoderBits)waitHandles[0].revents;
audio = (eAudioBits)waitHandles[1].revents;
ePollEvents seek = waitHandles[2].revents;
ePollEvents shutdown = waitHandles[3].revents;
if (decoderBits.HasFlag(eDecoderBits.Error))
{
throw new ApplicationException("poll(3) returned error status for the decoder device, probably the decoder failed");
}
if (audio.HasFlag(eAudioBits.Error))
{
throw new ApplicationException("poll(3) returned error status for the audio queue");
}
if (seek.HasFlag(ePollEvents.POLLERR))
{
throw new ApplicationException("poll(3) returned error status for the seek event handle");
}
if (shutdown.HasFlag(ePollEvents.POLLERR))
{
throw new ApplicationException("poll(3) returned error status for the shutdown event handle");
}
seekRequest = seek.HasFlag(ePollEvents.POLLIN);
shutdownRequest = shutdown.HasFlag(ePollEvents.POLLIN);
}
void runThread()
{
int playerHandlesCount = render.pollHandlesCount;
Span <pollfd> waitHandles = stackalloc pollfd[playerHandlesCount + 3];
render.setupPollHandles(waitHandles.Slice(0, playerHandlesCount));
setupInternalHandles(waitHandles, playerHandlesCount);
while (true)
{
LibC.poll(waitHandles);
if (waitHandles[playerHandlesCount + 1].revents.HasFlag(ePollEvents.POLLIN))
{
// Asked to shut down
return;
}
if (waitHandles[playerHandlesCount + 2].revents.HasFlag(ePollEvents.POLLIN))
{
// Got a seek event
if (!handleSeek())
{
return;
}
Logger.logDebug("Audio thread seek complete");
continue;
}
if (waitHandles[playerHandlesCount].revents.HasFlag(ePollEvents.POLLIN))
{
// Got a buffer with encoded frame.
// Dequeue from Linux kernel so the poll() no longer triggers the data available bit for that particular frame, enqueue into the thread-local managed-only queue.
// var d = queues.dequeueEncoded();
// encodedFrames.Enqueue( d );
pendingQueue.enqueue();
}
render.handlePollResult(this, waitHandles);
}
}
bool handleSeek()
{
// Get seek destination timestamp
TimeSpan seekDest;
lock (this)
{
if (!seekDestination.HasValue)
{
throw new ApplicationException("Seek event was set, but no destination timestamp");
}
seekEventHandle.reset();
seekDest = seekDestination.Value;
}
// Stop playing, drop data in the ALSA queue
render.beginSeek();
pendingQueue.discardAndFlush();
// Tell decoder thread it can now send new samples
m_clock?.drainComplete();
// Wait for video decoder to catch up
if (!m_clock.waitForVideoFrame())
{
return(false);
}
// Run the poll waiting for that special frame
Span <pollfd> waitHandles = stackalloc pollfd[3];
setupInternalHandles(waitHandles, 0);
bool foundTarget = false;
while (true)
{
LibC.poll(waitHandles);
if (waitHandles[1].revents.HasFlag(ePollEvents.POLLIN))
{
// Asked to shut down
return(false);
}
if (waitHandles[2].revents.HasFlag(ePollEvents.POLLIN))
{
// Got another seek event..
Logger.logWarning("Multiple seeks are not supported, probably won’t work");
lock (this)
{
if (!seekDestination.HasValue)
{
throw new ApplicationException("Seek event was set, but no destination timestamp");
}
seekEventHandle.reset();
seekDest = seekDestination.Value;
seekDestination = null;
}
}
if (waitHandles[0].revents.HasFlag(ePollEvents.POLLIN))
{
// Got a buffer with encoded frame.
var d = pendingQueue.queues.dequeueEncoded();
if (foundTarget)
{
pendingQueue.enqueue(d);
if (fillBuffer())
{
return(true);
}
}
else
{
if (d.timestamp != seekDest)
{
Logger.logVerbose("Audio thread got sample {0}, needs {1}", d.timestamp, seekDest);
// Not the one we're looking for
pendingQueue.queues.enqueueEmpty(d.index);
continue;
}
// Received seek destination frame.
Logger.logVerbose("Audio thread got the destination audio sample after seek, preparing to resume the playback");
pendingQueue.enqueue(d);
render.prepareEndSeek();
foundTarget = true;
if (fillBuffer())
{
return(true);
}
}
}
}
}
