ref: aac924f5cc55696f9771c3ed1a7a7f2d049e19dd
dir: /src/oss.c/
/* Copyright 1997 Chris Bagwell And Sundry Contributors
* This source code is freely redistributable and may be used for
* any purpose. This copyright notice must be maintained.
* Chris Bagwell And Sundry Contributors are not
* responsible for the consequences of using this software.
*
* Direct to Open Sound System (OSS) sound driver
* OSS is a popular unix sound driver for Intel x86 unices (eg. Linux)
* and several other unixes (such as SunOS/Solaris).
* This driver is compatible with OSS original source that was called
* USS, Voxware and TASD.
*
* added by Chris Bagwell (cbagwell@sprynet.com) on 2/19/96
* based on info grabed from vplay.c in Voxware snd-utils-3.5 package.
* and on LINUX_PLAYER patches added by Greg Lee
* which was originally from Directo to Sound Blaster device driver (sbdsp.c).
* SBLAST patches by John T. Kohl.
*
* Changes:
*
* Nov. 26, 1999 Stan Brooks <stabro@megsinet.net>
* Moved initialization code common to startread and startwrite
* into a single function ossdspinit().
*
*/
#include "sox_i.h"
#include <stdlib.h>
#include <stdio.h>
#include <fcntl.h>
#ifdef HAVE_SYS_SOUNDCARD_H
#include <sys/soundcard.h>
#endif
#ifdef HAVE_MACHINE_SOUNDCARD_H
#include <machine/soundcard.h>
#endif
#include <sys/ioctl.h>
typedef sox_fileinfo_t priv_t;
/* common r/w initialization code */
static int ossinit(sox_format_t * ft)
{
int sampletype, samplesize, dsp_stereo;
int tmp, rc;
priv_t *file = (priv_t *)ft->priv;
sox_signalinfo_t client_signal = ft->signal;
lsx_set_signal_defaults(&ft->signal);
if (ft->encoding.bits_per_sample == 8) {
sampletype = AFMT_U8;
samplesize = 8;
if (ft->encoding.encoding == SOX_ENCODING_UNKNOWN)
ft->encoding.encoding = SOX_ENCODING_UNSIGNED;
if (ft->encoding.encoding != SOX_ENCODING_UNSIGNED) {
lsx_report("OSS driver only supports unsigned with bytes");
lsx_report("Forcing to unsigned");
ft->encoding.encoding = SOX_ENCODING_UNSIGNED;
}
}
else if (ft->encoding.bits_per_sample == 16) {
/* Attempt to use endian that user specified */
if (ft->encoding.reverse_bytes)
sampletype = (MACHINE_IS_BIGENDIAN) ? AFMT_S16_LE : AFMT_S16_BE;
else
sampletype = (MACHINE_IS_BIGENDIAN) ? AFMT_S16_BE : AFMT_S16_LE;
samplesize = 16;
if (ft->encoding.encoding == SOX_ENCODING_UNKNOWN)
ft->encoding.encoding = SOX_ENCODING_SIGN2;
if (ft->encoding.encoding != SOX_ENCODING_SIGN2) {
lsx_report("OSS driver only supports signed with words");
lsx_report("Forcing to signed linear");
ft->encoding.encoding = SOX_ENCODING_SIGN2;
}
}
else {
/* Attempt to use endian that user specified */
if (ft->encoding.reverse_bytes)
sampletype = (MACHINE_IS_BIGENDIAN) ? AFMT_S16_LE : AFMT_S16_BE;
else
sampletype = (MACHINE_IS_BIGENDIAN) ? AFMT_S16_BE : AFMT_S16_LE;
samplesize = 16;
ft->encoding.bits_per_sample = 16;
ft->encoding.encoding = SOX_ENCODING_SIGN2;
lsx_report("OSS driver only supports bytes and words");
lsx_report("Forcing to signed linear word");
}
if (ft->signal.channels > 2) ft->signal.channels = 2;
if (ioctl(fileno(ft->fp), (size_t) SNDCTL_DSP_RESET, 0) < 0)
{
lsx_fail_errno(ft,SOX_EOF,"Unable to reset OSS driver. Possibly accessing an invalid file/device");
return(SOX_EOF);
}
/* Query the supported formats and find the best match
*/
rc = ioctl(fileno(ft->fp), SNDCTL_DSP_GETFMTS, &tmp);
if (rc == 0) {
if ((tmp & sampletype) == 0)
{
/* is 16-bit supported? */
if (samplesize == 16 && (tmp & (AFMT_S16_LE|AFMT_S16_BE)) == 0)
{
/* Must not like 16-bits, try 8-bits */
ft->encoding.bits_per_sample = 8;
ft->encoding.encoding = SOX_ENCODING_UNSIGNED;
lsx_report("OSS driver doesn't like signed words");
lsx_report("Forcing to unsigned bytes");
tmp = sampletype = AFMT_U8;
samplesize = 8;
}
/* is 8-bit supported */
else if (samplesize == 8 && (tmp & AFMT_U8) == 0)
{
ft->encoding.bits_per_sample = 16;
ft->encoding.encoding = SOX_ENCODING_SIGN2;
lsx_report("OSS driver doesn't like unsigned bytes");
lsx_report("Forcing to signed words");
sampletype = (MACHINE_IS_BIGENDIAN) ? AFMT_S16_BE : AFMT_S16_LE;
samplesize = 16;
}
/* determine which 16-bit format to use */
if (samplesize == 16 && (tmp & sampletype) == 0)
{
/* Either user requested something not supported
* or hardware doesn't support machine endian.
* Force to opposite as the above test showed
* it supports at least one of the two endians.
*/
sampletype = (sampletype == AFMT_S16_BE) ? AFMT_S16_LE : AFMT_S16_BE;
ft->encoding.reverse_bytes = !ft->encoding.reverse_bytes;
}
}
tmp = sampletype;
rc = ioctl(fileno(ft->fp), SNDCTL_DSP_SETFMT, &tmp);
}
/* Give up and exit */
if (rc < 0 || tmp != sampletype)
{
lsx_fail_errno(ft,SOX_EOF,"Unable to set the sample size to %d", samplesize);
return (SOX_EOF);
}
if (ft->signal.channels == 2) dsp_stereo = 1;
else dsp_stereo = 0;
tmp = dsp_stereo;
if (ioctl(fileno(ft->fp), SNDCTL_DSP_STEREO, &tmp) < 0)
{
lsx_warn("Couldn't set to %s", dsp_stereo? "stereo":"mono");
dsp_stereo = 0;
}
if (tmp != dsp_stereo)
{
if (client_signal.channels != 0)
lsx_warn("Sound card appears to support only %d channels. Overriding format", tmp+1);
ft->signal.channels = tmp + 1;
}
tmp = ft->signal.rate;
if (ioctl (fileno(ft->fp), SNDCTL_DSP_SPEED, &tmp) < 0 ||
(int)ft->signal.rate != tmp) {
/* If the rate the sound card is using is not within 1% of what
* the user specified then override the user setting.
* The only reason not to always override this is because of
* clock-rounding problems. Sound cards will sometimes use
* things like 44101 when you ask for 44100. No need overriding
* this and having strange output file rates for something that
* we can't hear anyways.
*/
if ((int)ft->signal.rate - tmp > (tmp * .01) ||
tmp - (int)ft->signal.rate > (tmp * .01)) {
if (client_signal.rate != 0)
lsx_warn("Unable to set audio speed to %g (set to %d)",
ft->signal.rate, tmp);
ft->signal.rate = tmp;
}
}
/* Find out block size to use last because the driver could compute
* its size based on specific rates/formats.
*/
file->size = 0;
ioctl (fileno(ft->fp), SNDCTL_DSP_GETBLKSIZE, &file->size);
if (file->size < 4 || file->size > 65536) {
lsx_fail_errno(ft,SOX_EOF,"Invalid audio buffer size %lu", (unsigned long)file->size);
return (SOX_EOF);
}
file->count = 0;
file->pos = 0;
file->buf = lsx_malloc(file->size);
if (ioctl(fileno(ft->fp), (size_t) SNDCTL_DSP_SYNC, NULL) < 0) {
lsx_fail_errno(ft,SOX_EOF,"Unable to sync dsp");
return (SOX_EOF);
}
/* Change to non-buffered I/O */
setvbuf(ft->fp, NULL, _IONBF, sizeof(char) * file->size);
return(SOX_SUCCESS);
}
SOX_FORMAT_HANDLER(oss)
{
static char const * const names[] = {"ossdsp", "oss", NULL};
static unsigned const write_encodings[] = {
SOX_ENCODING_SIGN2, 16, 0,
SOX_ENCODING_UNSIGNED, 8, 0,
0};
static sox_format_handler_t const handler = {SOX_LIB_VERSION_CODE,
"Open Sound Sytem device driver for unix-like systems",
names, SOX_FILE_DEVICE,
ossinit, lsx_rawread, lsx_rawstopread,
ossinit, lsx_rawwrite, lsx_rawstopwrite,
NULL, write_encodings, NULL, sizeof(priv_t)
};
return &handler;
}