/*static*/ int
alsa_init(cubeb ** context, char const * context_name)
{
cubeb * ctx;
int r;
int i;
int fd[2];
pthread_attr_t attr;
snd_pcm_t * dummy;
assert(context);
*context = NULL;
pthread_mutex_lock(&cubeb_alsa_mutex);
if (!cubeb_alsa_error_handler_set) {
snd_lib_error_set_handler(silent_error_handler);
cubeb_alsa_error_handler_set = 1;
}
pthread_mutex_unlock(&cubeb_alsa_mutex);
ctx = calloc(1, sizeof(*ctx));
assert(ctx);
ctx->ops = &alsa_ops;
r = pthread_mutex_init(&ctx->mutex, NULL);
assert(r == 0);
r = pipe(fd);
assert(r == 0);
for (i = 0; i < 2; ++i) {
fcntl(fd[i], F_SETFD, fcntl(fd[i], F_GETFD) | FD_CLOEXEC);
fcntl(fd[i], F_SETFL, fcntl(fd[i], F_GETFL) | O_NONBLOCK);
}
ctx->control_fd_read = fd[0];
ctx->control_fd_write = fd[1];
/* Force an early rebuild when alsa_run is first called to ensure fds and
nfds have been initialized. */
ctx->rebuild = 1;
r = pthread_attr_init(&attr);
assert(r == 0);
r = pthread_attr_setstacksize(&attr, 256 * 1024);
assert(r == 0);
r = pthread_create(&ctx->thread, &attr, alsa_run_thread, ctx);
assert(r == 0);
r = pthread_attr_destroy(&attr);
assert(r == 0);
/* Open a dummy PCM to force the configuration space to be evaluated so that
init_local_config_with_workaround can find and modify the default node. */
r = alsa_locked_pcm_open(&dummy, SND_PCM_STREAM_PLAYBACK, NULL);
if (r >= 0) {
alsa_locked_pcm_close(dummy);
}
ctx->is_pa = 0;
pthread_mutex_lock(&cubeb_alsa_mutex);
ctx->local_config = init_local_config_with_workaround(CUBEB_ALSA_PCM_NAME);
pthread_mutex_unlock(&cubeb_alsa_mutex);
if (ctx->local_config) {
ctx->is_pa = 1;
r = alsa_locked_pcm_open(&dummy, SND_PCM_STREAM_PLAYBACK, ctx->local_config);
/* If we got a local_config, we found a PA PCM. If opening a PCM with that
config fails with EINVAL, the PA PCM is too old for this workaround. */
if (r == -EINVAL) {
pthread_mutex_lock(&cubeb_alsa_mutex);
snd_config_delete(ctx->local_config);
pthread_mutex_unlock(&cubeb_alsa_mutex);
ctx->local_config = NULL;
} else if (r >= 0) {
alsa_locked_pcm_close(dummy);
}
}
*context = ctx;
return CUBEB_OK;
}
static inline int alsa_test_open(ao_device *device,
char *dev,
ao_sample_format *format)
{
ao_alsa_internal *internal = (ao_alsa_internal *) device->internal;
snd_pcm_hw_params_t *params;
int err;
adebug("Trying to open ALSA device '%s'\n",dev);
internal->local_config = init_local_config_with_workaround(device,dev);
if(internal->local_config)
err = snd_pcm_open_lconf(&(internal->pcm_handle), dev,
SND_PCM_STREAM_PLAYBACK, 0, internal->local_config);
else
err = snd_pcm_open(&(internal->pcm_handle), dev,
SND_PCM_STREAM_PLAYBACK, 0);
if(err){
adebug("Unable to open ALSA device '%s'\n",dev);
if(internal->local_config)
snd_config_delete(internal->local_config);
internal->local_config=NULL;
return err;
}
/* try to set up hw params */
err = alsa_set_hwparams(device,format);
if(err<0){
adebug("Unable to open ALSA device '%s'\n",dev);
snd_pcm_close(internal->pcm_handle);
if(internal->local_config)
snd_config_delete(internal->local_config);
internal->local_config=NULL;
internal->pcm_handle = NULL;
return err;
}
/* try to set up sw params */
err = alsa_set_swparams(device);
if(err<0){
adebug("Unable to open ALSA device '%s'\n",dev);
snd_pcm_close(internal->pcm_handle);
if(internal->local_config)
snd_config_delete(internal->local_config);
internal->local_config=NULL;
internal->pcm_handle = NULL;
return err;
}
/* this is a hack and fragile if the exact device detection code
flow changes! Nevertheless, this is a useful warning for users.
Never fail silently if we can help it! */
if(!strcasecmp(dev,"default")){
/* default device */
if(device->output_channels>2){
awarn("ALSA 'default' device plays only channels 0,1.\n");
}
}
if(!strcasecmp(dev,"default") || !strncasecmp(dev,"plug",4)){
if(format->bits>16){
awarn("ALSA '%s' device may only simulate >16 bit playback\n",dev);
}
}
/* success! */
return 0;
}
