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linux_a.c
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1996-05-20
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/*
TiMidity -- Experimental MIDI to WAVE converter
Copyright (C) 1995 Tuukka Toivonen <toivonen@clinet.fi>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
linux_audio.c
Functions to play sound on the VoxWare audio driver (Linux or FreeBSD)
*/
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#ifdef linux
#include <sys/ioctl.h> /* new with 1.2.0? Didn't need this under 1.1.64 */
#include <linux/soundcard.h>
#endif
#ifdef __FreeBSD__
#include <stdio.h>
#include <machine/soundcard.h>
#endif
#include "config.h"
#include "output.h"
#include "controls.h"
static int open_output(void); /* 0=success, 1=warning, -1=fatal error */
static void close_output(void);
static void output_data(int32 *buf, int32 count);
static void flush_output(void);
static void purge_output(void);
/* export the playback mode */
#define dpm linux_play_mode
PlayMode dpm = {
DEFAULT_RATE, PE_16BIT|PE_SIGNED,
-1,
{0}, /* default: get all the buffer fragments you can */
"Linux dsp device", 'd',
"/dev/dsp",
open_output,
close_output,
output_data,
flush_output,
purge_output
};
/*************************************************************************/
/* We currently only honor the PE_MONO bit, the sample rate, and the
number of buffer fragments. We try 16-bit signed data first, and
then 8-bit unsigned if it fails. If you have a sound device that
can't handle either, let me know. */
static int open_output(void)
{
int fd, tmp, i, warnings=0;
/* Open the audio device */
fd=open(dpm.name, O_RDWR | O_NDELAY);
if (fd<0)
{
ctl->cmsg(CMSG_ERROR, VERB_NORMAL, "%s: %s",
dpm.name, sys_errlist[errno]);
return -1;
}
/* They can't mean these */
dpm.encoding &= ~(PE_ULAW|PE_BYTESWAP);
/* Set sample width to whichever the user wants. If it fails, try
the other one. */
i=tmp=(dpm.encoding & PE_16BIT) ? 16 : 8;
if (ioctl(fd, SNDCTL_DSP_SAMPLESIZE, &tmp)<0 || tmp!=i)
{
/* Try the other one */
i=tmp=(dpm.encoding & PE_16BIT) ? 8 : 16;
if (ioctl(fd, SNDCTL_DSP_SAMPLESIZE, &tmp)<0 || tmp!=i)
{
ctl->cmsg(CMSG_ERROR, VERB_NORMAL,
"%s doesn't support 16- or 8-bit sample width",
dpm.name);
close(fd);
return -1;
}
ctl->cmsg(CMSG_WARNING, VERB_VERBOSE,
"Sample width adjusted to %d bits", tmp);
dpm.encoding ^= PE_16BIT;
warnings=1;
}
if (dpm.encoding & PE_16BIT)
dpm.encoding |= PE_SIGNED;
else
dpm.encoding &= ~PE_SIGNED;
/* Try stereo or mono, whichever the user wants. If it fails, try
the other. */
i=tmp=(dpm.encoding & PE_MONO) ? 0 : 1;
if ((ioctl(fd, SNDCTL_DSP_STEREO, &tmp)<0) || tmp!=i)
{
i=tmp=(dpm.encoding & PE_MONO) ? 1 : 0;
if ((ioctl(fd, SNDCTL_DSP_STEREO, &tmp)<0) || tmp!=i)
{
ctl->cmsg(CMSG_ERROR, VERB_NORMAL,
"%s doesn't support mono or stereo samples",
dpm.name);
close(fd);
return -1;
}
if (tmp==0) dpm.encoding |= PE_MONO;
else dpm.encoding &= ~PE_MONO;
ctl->cmsg(CMSG_WARNING, VERB_VERBOSE, "Sound adjusted to %sphonic",
(tmp==0) ? "mono" : "stereo");
warnings=1;
}
/* Set the sample rate */
tmp=dpm.rate;
if (ioctl(fd, SNDCTL_DSP_SPEED, &tmp)<0)
{
ctl->cmsg(CMSG_ERROR, VERB_NORMAL,
"%s doesn't support a %d Hz sample rate",
dpm.name, dpm.rate);
close(fd);
return -1;
}
if (tmp != dpm.rate)
{
dpm.rate=tmp;
ctl->cmsg(CMSG_WARNING, VERB_VERBOSE,
"Output rate adjusted to %d Hz", dpm.rate);
warnings=1;
}
/* Older VoxWare drivers don't have buffer fragment capabilities */
#ifdef SNDCTL_DSP_SETFRAGMENT
/* Set buffer fragments (in extra_param[0]) */
tmp=AUDIO_BUFFER_BITS;
if (!(dpm.encoding & PE_MONO)) tmp++;
if (dpm.encoding & PE_16BIT) tmp++;
tmp |= (dpm.extra_param[0]<<16);
i=tmp;
if (ioctl(fd, SNDCTL_DSP_SETFRAGMENT, &tmp)<0)
{
ctl->cmsg(CMSG_WARNING, VERB_NORMAL,
"%s doesn't support %d-byte buffer fragments", dpm.name, (1<<i));
/* It should still work in some fashion. We should use a
secondary buffer anyway -- 64k isn't enough. */
warnings=1;
}
#else
if (dpm.extra_param[0])
{
ctl->cmsg(CMSG_WARNING, VERB_NORMAL,
"%s doesn't support buffer fragments", dpm.name);
warnings=1;
}
#endif
dpm.fd=fd;
return warnings;
}
static void output_data(int32 *buf, int32 count)
{
if (!(dpm.encoding & PE_MONO)) count*=2; /* Stereo samples */
if (dpm.encoding & PE_16BIT)
{
/* Convert data to signed 16-bit PCM */
s32tos16(buf, count);
/* Write the data out. Linux likes to give an EINTR if you suspend
a program while waiting on a write, so we may need to retry. */
while ((-1==write(dpm.fd, buf, count * 2)) && errno==EINTR)
;
}
else
{
/* Convert to 8-bit unsigned and write out. */
s32tou8(buf, count);
while ((-1==write(dpm.fd, buf, count)) && errno==EINTR)
;
}
}
static void close_output(void)
{
close(dpm.fd);
}
static void flush_output(void)
{
ioctl(dpm.fd, SNDCTL_DSP_SYNC);
}
static void purge_output(void)
{
ioctl(dpm.fd, SNDCTL_DSP_RESET);
}