audio: Better handling of ProvidesOwnCallbackThread backends.

main
Ryan C. Gordon 2023-07-03 11:37:40 -04:00
parent 1dffb72c1d
commit a8323ebe68
No known key found for this signature in database
GPG Key ID: FA148B892AB48044
2 changed files with 18 additions and 7 deletions

View File

@ -388,7 +388,7 @@ void SDL_AudioDeviceDisconnected(SDL_AudioDevice *device)
}
// if there's an audio thread, don't free until thread is terminating, otherwise free stuff now.
const SDL_bool should_destroy = (device->thread == NULL);
const SDL_bool should_destroy = SDL_AtomicGet(&device->thread_alive) ? SDL_FALSE : SDL_TRUE;
SDL_UnlockMutex(device->lock);
// Post the event, if we haven't tried to before and if it's desired
@ -641,6 +641,7 @@ void SDL_QuitAudio(void)
void SDL_AudioThreadFinalize(SDL_AudioDevice *device)
{
SDL_assert(SDL_AtomicGet(&device->thread_alive));
if (SDL_AtomicGet(&device->condemned)) {
if (device->thread) {
SDL_DetachThread(device->thread); // no one is waiting for us, just detach ourselves.
@ -648,6 +649,7 @@ void SDL_AudioThreadFinalize(SDL_AudioDevice *device)
}
DestroyPhysicalAudioDevice(device);
}
SDL_AtomicSet(&device->thread_alive, 0);
}
// Output device thread. This is split into chunks, so backends that need to control this directly can use the pieces they need without duplicating effort.
@ -1053,15 +1055,18 @@ int SDL_GetAudioDeviceFormat(SDL_AudioDeviceID devid, SDL_AudioSpec *spec)
// this expects the device lock to be held.
static void ClosePhysicalAudioDevice(SDL_AudioDevice *device)
{
if (device->thread != NULL) {
SDL_assert(current_audio.impl.ProvidesOwnCallbackThread || ((device->thread == NULL) == (SDL_AtomicGet(&device->thread_alive) == 0)));
if (SDL_AtomicGet(&device->thread_alive)) {
SDL_AtomicSet(&device->shutdown, 1);
SDL_WaitThread(device->thread, NULL);
device->thread = NULL;
SDL_AtomicSet(&device->shutdown, 0);
if (device->thread != NULL) {
SDL_WaitThread(device->thread, NULL);
device->thread = NULL;
}
}
if (device->is_opened) {
current_audio.impl.CloseDevice(device);
current_audio.impl.CloseDevice(device); // if ProvidesOwnCallbackThread, this must join on any existing device thread before returning!
device->is_opened = SDL_FALSE;
}
@ -1073,6 +1078,7 @@ static void ClosePhysicalAudioDevice(SDL_AudioDevice *device)
SDL_memcpy(&device->spec, &device->default_spec, sizeof (SDL_AudioSpec));
device->sample_frames = 0;
device->silence_value = SDL_GetSilenceValueForFormat(device->spec.format);
SDL_AtomicSet(&device->shutdown, 0); // ready to go again.
}
void SDL_CloseAudioDevice(SDL_AudioDeviceID devid)
@ -1204,6 +1210,7 @@ static int OpenPhysicalAudioDevice(SDL_AudioDevice *device, const SDL_AudioSpec
}
// Start the audio thread if necessary
SDL_AtomicSet(&device->thread_alive, 1);
if (!current_audio.impl.ProvidesOwnCallbackThread) {
const size_t stacksize = 0; // just take the system default, since audio streams might have callbacks.
char threadname[64];
@ -1211,6 +1218,7 @@ static int OpenPhysicalAudioDevice(SDL_AudioDevice *device, const SDL_AudioSpec
device->thread = SDL_CreateThreadInternal(device->iscapture ? CaptureAudioThread : OutputAudioThread, threadname, stacksize, device);
if (device->thread == NULL) {
SDL_AtomicSet(&device->thread_alive, 0);
ClosePhysicalAudioDevice(device);
return SDL_SetError("Couldn't create audio thread");
}

View File

@ -118,7 +118,7 @@ typedef struct SDL_AudioDriverImpl
void (*Deinitialize)(void);
/* Some flags to push duplicate code into the core and reduce #ifdefs. */
SDL_bool ProvidesOwnCallbackThread;
SDL_bool ProvidesOwnCallbackThread; // !!! FIXME: rename this, it's not a callback thread anymore.
SDL_bool HasCaptureSupport;
SDL_bool OnlyHasDefaultOutputDevice;
SDL_bool OnlyHasDefaultCaptureDevice;
@ -246,6 +246,9 @@ struct SDL_AudioDevice
/* non-zero if this was a disconnected default device and we're waiting for its replacement. */
SDL_AtomicInt zombie;
/* non-zero if this has a thread running (which might be `thread` or something provided by the backend!) */
SDL_AtomicInt thread_alive;
/* SDL_TRUE if this is a capture device instead of an output device */
SDL_bool iscapture;