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Added direct_write transfer method

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This commit is contained in:
Jaroslav Kysela 2001-10-18 18:04:26 +00:00
parent 0259e6877e
commit d333c1e9de
1 changed files with 34 additions and 0 deletions
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34
test/pcm.c
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@ -419,6 +419,39 @@ static int direct_loop(snd_pcm_t *handle,
} }
} }
/*
* Transfer method - direct write only using mmap_write functions
*/
static int direct_write_loop(snd_pcm_t *handle,
signed short *samples,
snd_pcm_channel_area_t *areas)
{
double phase = 0;
signed short *ptr;
int err, cptr;
while (1) {
generate_sine(areas, 0, period_size, &phase);
ptr = samples;
cptr = period_size;
while (cptr > 0) {
err = snd_pcm_mmap_writei(handle, ptr, cptr);
if (err == -EAGAIN)
continue;
if (err < 0) {
if (xrun_recovery(handle, err) < 0) {
printf("Write error: %s\n", snd_strerror(err));
exit(EXIT_FAILURE);
}
break; /* skip one period */
}
ptr += err * channels;
cptr -= err;
}
}
}
/* /*
* *
*/ */
@ -437,6 +470,7 @@ static struct transfer_method transfer_methods[] = {
{ "async", SND_PCM_ACCESS_RW_INTERLEAVED, async_loop }, { "async", SND_PCM_ACCESS_RW_INTERLEAVED, async_loop },
{ "direct_interleaved", SND_PCM_ACCESS_MMAP_INTERLEAVED, direct_loop }, { "direct_interleaved", SND_PCM_ACCESS_MMAP_INTERLEAVED, direct_loop },
{ "direct_noninterleaved", SND_PCM_ACCESS_MMAP_NONINTERLEAVED, direct_loop }, { "direct_noninterleaved", SND_PCM_ACCESS_MMAP_NONINTERLEAVED, direct_loop },
{ "direct_write", SND_PCM_ACCESS_MMAP_INTERLEAVED, direct_write_loop },
{ NULL, SND_PCM_ACCESS_RW_INTERLEAVED, NULL } { NULL, SND_PCM_ACCESS_RW_INTERLEAVED, NULL }
}; };