/* prepare the audio device for playback */
int ao_plugin_open(ao_device *device, ao_sample_format *format)
{
ao_alsa_internal *internal = (ao_alsa_internal *) device->internal;
int err;
/* Get the ALSA bitformat first to make sure it's valid */
err = alsa_get_sample_bitformat(format->bits,
device->client_byte_format == AO_FMT_BIG);
if (err < 0)
goto error;
internal->bitformat = err;
/* Open the ALSA device */
internal->cmd = "snd_pcm_open";
err = snd_pcm_open(&(internal->pcm_handle), internal->dev,
SND_PCM_STREAM_PLAYBACK, 0);
if (err < 0) {
internal->pcm_handle = NULL;
goto error;
}
/* Set up the hardware parameters, ie sample and buffer specs */
err = alsa_set_hwparams(internal, format);
if (err < 0)
goto error;
/* Set up the software parameters, ie de-buffering specs */
err = alsa_set_swparams(internal);
if (err < 0)
goto error;
/* alsa's endinness will be the same as the application's */
if (format->bits > 8)
device->driver_byte_format = device->client_byte_format;
return 1;
error:
fprintf(stderr, "ALSA %s error: %s\n",
internal->cmd, snd_strerror(err));
if (internal->pcm_handle) {
snd_pcm_close(internal->pcm_handle);
internal->pcm_handle = NULL;
}
return 0;
}
/* prepare the audio device for playback */
int ao_plugin_open(ao_device *device, ao_sample_format *format)
{
ao_alsa_internal *internal = (ao_alsa_internal *) device->internal;
int err,prebits;
/* Get the ALSA bitformat first to make sure it's valid */
err = alsa_get_sample_bitformat(format->bits,
device->client_byte_format == AO_FMT_BIG,device);
if (err < 0){
aerror("Invalid byte format\n");
return 0;
}
internal->bitformat = err;
/* Alsa can only use padded 24 bit formatting */
if(format->bits>16 && format->bits<=24){
internal->padbuffer = calloc(4096,1);
internal->padoutw = 32;
}else{
internal->padbuffer = 0;
internal->padoutw = 0;
}
prebits = format->bits;
/* Open the ALSA device */
err=0;
if(!internal->dev){
if(internal->id<0){
char *tmp=NULL;
/* we don't try just 'default' as it's a plug device that
will accept any number of channels but usually plays back
everything as stereo. */
switch(device->output_channels){
default:
case 8:
case 7:
err = alsa_test_open(device, tmp="surround71", format);
break;
case 4:
case 3:
err = alsa_test_open(device, tmp="surround40", format);
if(err==0)break;
case 6:
case 5:
err = alsa_test_open(device, tmp="surround51", format);
break;
case 2:
err = alsa_test_open(device, tmp="front", format);
case 1:
break;
}
if(err){
awarn("Unable to open surround playback. Trying default device...\n");
tmp=NULL;
}
if(!tmp)
err = alsa_test_open(device, tmp="default", format);
internal->dev=strdup(tmp);
}else{
char tmp[80];
sprintf(tmp,"hw:%d",internal->id);
internal->dev=strdup(tmp);
err = alsa_test_open(device, internal->dev, format);
}
}else
err = alsa_test_open(device, internal->dev, format);
if (err < 0) {
aerror("Unable to open ALSA device '%s' for playback => %s\n",
internal->dev, snd_strerror(err));
return 0;
}
if(prebits != format->bits){
internal->padbuffer = calloc(4096,1);
internal->padoutw = (format->bits+7)/8;
format->bits=prebits;
}
adebug("Using ALSA device '%s'\n",internal->dev);
{
snd_pcm_sframes_t sframes;
if(snd_pcm_delay (internal->pcm_handle, &sframes)){
internal->static_delay=0;
}else{
internal->static_delay=sframes;
}
}
/* save the sample size in bytes for posterity */
internal->sample_size = format->bits * device->output_channels / 8;
/* alsa's endinness will be the same as the application's */
if (format->bits > 8)
device->driver_byte_format = device->client_byte_format;
if(strcasecmp(internal->dev,"default")){
if(strncasecmp(internal->dev,"surround",8)){
if(device->output_channels>2 && device->verbose>=0){
awarn("No way to determine hardware %d channel mapping of\n"
"ALSA device '%s'.\n",device->output_channels, internal->dev);
if(device->inter_matrix){
free(device->inter_matrix);
device->inter_matrix=NULL;
}
}
}
}
return 1;
}
