ref: d8c8e7b910b05f6e13d4ffb5baa634b13d06afaa
dir: /src/alsa.c/
#if defined(ALSA_PLAYER)
/*
* Copyright 1997 Jimen Ching And Sundry Contributors
* This source code is freely redistributable and may be used for
* any purpose. This copyright notice must be maintained.
* Jimen Ching And Sundry Contributors are not
* responsible for the consequences of using this software.
*/
/* Direct to ALSA sound driver
*
* added by Jimen Ching (jching@flex.com) 19990207
* based on info grabed from aplay.c in alsa-utils package.
*/
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <fcntl.h>
#include <linux/asound.h>
#include <sys/ioctl.h>
#include "st.h"
/*
* Do anything required before you start reading samples.
* Read file header.
* Find out sampling rate,
* size and style of samples,
* mono/stereo/quad.
*/
int st_alsastartread(ft)
ft_t ft;
{
int bps, fmt, size;
snd_pcm_capture_info_t c_info;
snd_pcm_format_t format;
snd_pcm_capture_params_t c_params;
memset(&c_info, 0, sizeof(c_info));
ioctl(fileno(ft->fp), SND_PCM_IOCTL_CAPTURE_INFO, &c_info);
ft->file.count = 0;
ft->file.pos = 0;
ft->file.eof = 0;
ft->file.size = c_info.buffer_size;
if ((ft->file.buf = malloc (ft->file.size)) == NULL) {
fail("unable to allocate output buffer of size %d", ft->file.size);
return (ST_EOF)
}
if (ft->info.rate < c_info.min_rate) ft->info.rate = 2 * c_info.min_rate;
else if (ft->info.rate > c_info.max_rate) ft->info.rate = c_info.max_rate;
if (ft->info.channels == -1) ft->info.channels = c_info.min_channels;
else if (ft->info.channels > c_info.max_channels) ft->info.channels = c_info.max_channels;
if (ft->info.size == -1) {
if ((c_info.hw_formats & SND_PCM_FMT_U8) || (c_info.hw_formats & SND_PCM_FMT_S8))
ft->info.size = ST_SIZE_BYTE;
else
ft->info.size = ST_SIZE_WORD;
}
if (ft->info.style == -1) {
if ((c_info.hw_formats & SND_PCM_FMT_S16_LE) || (c_info.hw_formats & SND_PCM_FMT_S8))
ft->info.style = ST_ENCODING_SIGN2;
else
ft->info.style = ST_ENCODING_UNSIGNED;
}
if (ft->info.size == ST_SIZE_BYTE) {
switch (ft->info.style)
{
case ST_ENCODING_SIGN2:
if (!(c_info.hw_formats & SND_PCM_FMT_S8))
fail("ALSA driver does not support signed byte samples");
fmt = SND_PCM_SFMT_S8;
break;
case ST_ENCODING_UNSIGNED:
if (!(c_info.hw_formats & SND_PCM_FMT_U8))
fail("ALSA driver does not support unsigned byte samples");
fmt = SND_PCM_SFMT_U8;
break;
default:
fail("Hardware does not support %s output", styles[ft->info.style]);
return(ST_EOF);
break;
}
}
else {
switch (ft->info.style)
{
case ST_ENCODING_SIGN2:
if (!(c_info.hw_formats & SND_PCM_FMT_S16_LE))
fail("ALSA driver does not support signed word samples");
fmt = SND_PCM_SFMT_S16_LE;
break;
case ST_ENCODING_UNSIGNED:
if (!(c_info.hw_formats & SND_PCM_FMT_U16_LE))
fail("ALSA driver does not support unsigned word samples");
fmt = SND_PCM_SFMT_U16_LE;
break;
default:
fail("Hardware does not support %s output", styles[ft->info.style]);
return(ST_EOF);
break;
}
}
memset(&format, 0, sizeof(format));
format.format = fmt;
format.rate = ft->info.rate;
format.channels = ft->info.channels;
ioctl(fileno(ft->fp), SND_PCM_IOCTL_CAPTURE_FORMAT, &format);
size = ft->file.size;
bps = format.rate * format.channels;
if (ft->info.size == WORD) bps <<= 1;
bps >>= 2;
while (size > bps) size >>= 1;
if (size < 16) size = 16;
memset(&c_params, 0, sizeof(c_params));
c_params.fragment_size = size;
c_params.fragments_min = 1;
ioctl(fileno(ft->fp), SND_PCM_IOCTL_CAPTURE_PARAMS, &c_params);
/* Change to non-buffered I/O */
setvbuf(ft->fp, NULL, _IONBF, sizeof(char) * ft->file.size);
sigintreg(ft); /* Prepare to catch SIGINT */
return (ST_SUCCESS);
}
int st_alsastartwrite(ft)
ft_t ft;
{
int bps, fmt, size;
snd_pcm_playback_info_t p_info;
snd_pcm_format_t format;
snd_pcm_playback_params_t p_params;
memset(&p_info, 0, sizeof(p_info));
ioctl(fileno(ft->fp), SND_PCM_IOCTL_PLAYBACK_INFO, &p_info);
ft->file.pos = 0;
ft->file.eof = 0;
ft->file.size = p_info.buffer_size;
if ((ft->file.buf = malloc (ft->file.size)) == NULL) {
fail("unable to allocate output buffer of size %d", ft->file.size);
return(ST_EOF);
}
if (ft->info.rate < p_info.min_rate) ft->info.rate = 2 * p_info.min_rate;
else if (ft->info.rate > p_info.max_rate) ft->info.rate = p_info.max_rate;
if (ft->info.channels == -1) ft->info.channels = p_info.min_channels;
else if (ft->info.channels > p_info.max_channels) ft->info.channels = p_info.max_channels;
if (ft->info.size == -1) {
if ((p_info.hw_formats & SND_PCM_FMT_U8) || (p_info.hw_formats & SND_PCM_FMT_S8))
ft->info.size = ST_SIZE_BYTE;
else
ft->info.size = ST_SIZE_WORD;
}
if (ft->info.style == -1) {
if ((p_info.hw_formats & SND_PCM_FMT_S16_LE) || (p_info.hw_formats & SND_PCM_FMT_S8))
ft->info.style = ST_ENCODING_SIGN2;
else
ft->info.style = ST_ENCODING_UNSIGNED;
}
if (ft->info.size == ST_SIZE_BYTE) {
switch (ft->info.style)
{
case ST_ENCODING_SIGN2:
if (!(p_info.hw_formats & SND_PCM_FMT_S8))
fail("ALSA driver does not support signed byte samples");
fmt = SND_PCM_SFMT_S8;
break;
case ST_ENCODING_UNSIGNED:
if (!(p_info.hw_formats & SND_PCM_FMT_U8))
fail("ALSA driver does not support unsigned byte samples");
fmt = SND_PCM_SFMT_U8;
break;
default:
fail("Hardware does not support %s output", styles[ft->info.style]);
return(ST_EOF);
break;
}
}
else {
switch (ft->info.style)
{
case ST_ENCODING_SIGN2:
if (!(p_info.hw_formats & SND_PCM_FMT_S16_LE))
fail("ALSA driver does not support signed word samples");
fmt = SND_PCM_SFMT_S16_LE;
break;
case ST_ENCODING_UNSIGNED:
if (!(p_info.hw_formats & SND_PCM_FMT_U16_LE))
fail("ALSA driver does not support unsigned word samples");
fmt = SND_PCM_SFMT_U16_LE;
break;
default:
fail("Hardware does not support %s output", styles[ft->info.style]);
return(ST_EOF);
break;
}
}
memset(&format, 0, sizeof(format));
format.format = fmt;
format.rate = ft->info.rate;
format.channels = ft->info.channels;
ioctl(fileno(ft->fp), SND_PCM_IOCTL_PLAYBACK_FORMAT, &format);
size = ft->file.size;
bps = format.rate * format.channels;
if (ft->info.size == WORD) bps <<= 1;
bps >>= 2;
while (size > bps) size >>= 1;
if (size < 16) size = 16;
memset(&p_params, 0, sizeof(p_params));
p_params.fragment_size = size;
p_params.fragments_max = -1;
p_params.fragments_room = 1;
ioctl(fileno(ft->fp), SND_PCM_IOCTL_PLAYBACK_PARAMS, &p_params);
/* Change to non-buffered I/O */
setvbuf(ft->fp, NULL, _IONBF, sizeof(char) * ft->file.size);
}
#endif