static HRESULT SetFormat(IDsDriverBufferImpl *This, LPWAVEFORMATEX pwfx)
{
snd_pcm_t *pcm = NULL;
snd_pcm_hw_params_t *hw_params = This->hw_params;
unsigned int buffer_time = 500000;
snd_pcm_format_t format = -1;
snd_pcm_uframes_t psize;
DWORD rate = pwfx->nSamplesPerSec;
int err=0;
switch (pwfx->wBitsPerSample)
{
case 8:
format = SND_PCM_FORMAT_U8;
break;
case 16:
format = SND_PCM_FORMAT_S16_LE;
break;
case 24:
format = SND_PCM_FORMAT_S24_3LE;
break;
case 32:
format = SND_PCM_FORMAT_S32_LE;
break;
default:
FIXME("Unsupported bpp: %d\n", pwfx->wBitsPerSample);
return DSERR_GENERIC;
}
err = snd_pcm_open(&pcm, WOutDev[This->drv->wDevID].pcmname, SND_PCM_STREAM_PLAYBACK, SND_PCM_NONBLOCK);
if (err < 0)
{
if (errno != EBUSY || !This->pcm)
{
WARN("Cannot open sound device: %s\n", snd_strerror(err));
return DSERR_GENERIC;
}
snd_pcm_drop(This->pcm);
snd_pcm_close(This->pcm);
This->pcm = NULL;
err = snd_pcm_open(&pcm, WOutDev[This->drv->wDevID].pcmname, SND_PCM_STREAM_PLAYBACK, SND_PCM_NONBLOCK);
if (err < 0)
{
WARN("Cannot open sound device: %s\n", snd_strerror(err));
return DSERR_BUFFERLOST;
}
}
/* Set some defaults */
snd_pcm_hw_params_any(pcm, hw_params);
err = snd_pcm_hw_params_set_channels(pcm, hw_params, pwfx->nChannels);
if (err < 0) {
WARN("Could not set channels to %d\n", pwfx->nChannels);
goto err;
}
err = snd_pcm_hw_params_set_format(pcm, hw_params, format);
if (err < 0) {
WARN("Could not set format to %d bpp\n", pwfx->wBitsPerSample);
goto err;
}
/* Alsa's rate resampling is only used if the application specifically requests
* a buffer at a certain frequency, else it is better to disable it due to unwanted
* side effects, which may include: Less granular pointer, changing buffer sizes, etc
*/
#if SND_LIB_VERSION >= 0x010009
snd_pcm_hw_params_set_rate_resample(pcm, hw_params, 0);
#endif
err = snd_pcm_hw_params_set_rate_near(pcm, hw_params, &rate, NULL);
if (err < 0) {
rate = pwfx->nSamplesPerSec;
WARN("Could not set rate\n");
goto err;
}
if (!ALSA_NearMatch(rate, pwfx->nSamplesPerSec))
{
WARN("Could not set sound rate to %d, but instead to %d\n", pwfx->nSamplesPerSec, rate);
pwfx->nSamplesPerSec = rate;
pwfx->nAvgBytesPerSec = rate * pwfx->nBlockAlign;
/* Let DirectSound detect this */
}
snd_pcm_hw_params_set_periods_integer(pcm, hw_params);
snd_pcm_hw_params_set_buffer_time_near(pcm, hw_params, &buffer_time, NULL);
buffer_time = 10000;
snd_pcm_hw_params_set_period_time_near(pcm, hw_params, &buffer_time, NULL);
err = snd_pcm_hw_params(pcm, hw_params);
err = snd_pcm_sw_params(pcm, This->sw_params);
snd_pcm_prepare(pcm);
err = snd_pcm_hw_params_get_period_size(hw_params, &psize, NULL);
TRACE("Period size is: %lu\n", psize);
/* ALSA needs at least 3 buffers to work successfully */
This->mmap_commitahead = 3 * psize;
while (This->mmap_commitahead <= 512)
This->mmap_commitahead += psize;
if (This->pcm)
{
snd_pcm_drop(This->pcm);
snd_pcm_close(This->pcm);
}
This->pcm = pcm;
snd_pcm_prepare(This->pcm);
DSDB_CreateMMAP(This);
return S_OK;
err:
if (err < 0)
WARN("Failed to apply changes: %s\n", snd_strerror(err));
if (!This->pcm)
This->pcm = pcm;
else
snd_pcm_close(pcm);
if (This->pcm)
snd_pcm_hw_params_current(This->pcm, This->hw_params);
return DSERR_BADFORMAT;
}
void stop_audio(void)
{
snd_pcm_drop(playback_handle);
}
