pandory500/SDL-mirror
2
0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

coreaudio: changed device close procedure to prevent long hangs in some cases.

Browse source 
The audioqueue thread needs to keep running, and processing the CFRunLoop
until the AudioQueue is disposed of, otherwise CoreAudio will hang waiting for
final data to feed the device.

At least, I think this is how it all works. It definitely fixes the bug here!

Since AudioQueueDispose() calls AudioQueueStop() internally, there's no need
for our thread to handle this, either, which is good because the AudioQueue
would be disposed by this point. So now the AudioQueue is disposed first, and
then our thread is joined, and everything works out okay.

Just in case, we mark the device "paused" before setting everything in motion,
so any further callbacks from CoreAudio will write silence and not fire the
app's audio callback again.

Fixes Bugzilla #3868.

--HG--
extra : rebase_source : 3b8ba6f8c5af56b8193ea1bd96ef8b9111533f87
This commit is contained in:
Ryan C. Gordon 2017-10-13 01:15:29 -04:00
parent c78d61d079
commit e8c14464e7
1 changed files with 8 additions and 8 deletions
Download patch file Download diff file Expand all files Collapse all files

16
src/audio/coreaudio/SDL_coreaudio.m
View file

@ -541,15 +541,18 @@ COREAUDIO_CloseDevice(_THIS)
update_audio_session(this, SDL_FALSE);
#endif
if (this->hidden->thread) {
SDL_AtomicSet(&this->hidden->shutdown, 1);
SDL_WaitThread(this->hidden->thread, NULL);
}
/* if callback fires again, feed silence; don't call into the app. */
SDL_AtomicSet(&this->paused, 1);
if (this->hidden->audioQueue) {
AudioQueueDispose(this->hidden->audioQueue, 1);
}
if (this->hidden->thread) {
SDL_AtomicSet(&this->hidden->shutdown, 1);
SDL_WaitThread(this->hidden->thread, NULL);
}
if (this->hidden->ready_semaphore) {
SDL_DestroySemaphore(this->hidden->ready_semaphore);
}
@ -731,12 +734,9 @@ audioqueue_thread(void *arg)
CFRunLoopRunInMode(kCFRunLoopDefaultMode, 0.10, 1);
}
if (this->iscapture) { /* just stop immediately for capture devices. */
AudioQueueStop(this->hidden->audioQueue, 1);
} else { /* Drain off any pending playback. */
if (!this->iscapture) { /* Drain off any pending playback. */
const CFTimeInterval secs = (((this->spec.size / (SDL_AUDIO_BITSIZE(this->spec.format) / 8)) / this->spec.channels) / ((CFTimeInterval) this->spec.freq)) * 2.0;
CFRunLoopRunInMode(kCFRunLoopDefaultMode, secs, 0);
AudioQueueStop(this->hidden->audioQueue, 0);
}
return 0;