ref: 021c7886e4ecfe58022848aa3f4877e1986e3089
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_UNISTD_H
#include <unistd.h>
#endif
/* these appear in the sys/soundcard.h of OSS 4.x, and in Linux's
* sound/core/oss/pcm_oss.c (2.6.24 and later), but are typically
* not included in system header files.
*/
#ifndef AFMT_S32_LE
#define AFMT_S32_LE 0x00001000
#endif
#ifndef AFMT_S32_BE
#define AFMT_S32_BE 0x00002000
#endif
#include <sys/ioctl.h>
typedef struct
{
char* pOutput;
unsigned cOutput;
int device;
unsigned sample_shift;
} priv_t;
/* common r/w initialization code */
static int ossinit(sox_format_t* ft)
{
int sampletype, samplesize;
int tmp, rc;
char const* szDevname;
priv_t* pPriv = (priv_t*)ft->priv;
if (ft->filename == 0 || ft->filename[0] == 0 || !strcasecmp("default", ft->filename))
{
szDevname = getenv("OSS_AUDIODEV");
if (szDevname != NULL)
{
lsx_report("Using device name from OSS_AUDIODEV environment variable: %s", szDevname);
}
else
{
szDevname = "/dev/dsp";
lsx_report("Using default OSS device name: %s", szDevname);
}
}
else
{
szDevname = ft->filename;
lsx_report("Using user-specified device name: %s", szDevname);
}
pPriv->device = open(
szDevname,
ft->mode == 'r' ? O_RDONLY : O_WRONLY);
if (pPriv->device < 0) {
lsx_fail_errno(ft, errno, "open failed for device: %s", szDevname);
return SOX_EOF;
}
if (ft->encoding.bits_per_sample == 8) {
sampletype = AFMT_U8;
samplesize = 8;
pPriv->sample_shift = 0;
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;
pPriv->sample_shift = 1;
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 if (ft->encoding.bits_per_sample == 32) {
/* Attempt to use endian that user specified */
if (ft->encoding.reverse_bytes)
sampletype = (MACHINE_IS_BIGENDIAN) ? AFMT_S32_LE : AFMT_S32_BE;
else
sampletype = (MACHINE_IS_BIGENDIAN) ? AFMT_S32_BE : AFMT_S32_LE;
samplesize = 32;
pPriv->sample_shift = 2;
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;
pPriv->sample_shift = 1;
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");
}
ft->signal.channels = 2;
if (ioctl(pPriv->device, (size_t) SNDCTL_DSP_RESET, 0) < 0)
{
lsx_fail_errno(ft,SOX_EOF,"Unable to reset OSS device %s. Possibly accessing an invalid file/device", szDevname);
return(SOX_EOF);
}
/* Query the supported formats and find the best match
*/
rc = ioctl(pPriv->device, 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;
pPriv->sample_shift = 0;
}
/* 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;
pPriv->sample_shift = 1;
}
/* 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(pPriv->device, 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);
}
tmp = 1;
if (ioctl(pPriv->device, SNDCTL_DSP_STEREO, &tmp) < 0 || tmp != 1)
{
lsx_warn("Couldn't set to stereo");
ft->signal.channels = 1;
}
tmp = ft->signal.rate;
if (ioctl(pPriv->device, 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))
ft->signal.rate = tmp;
}
if (ioctl(pPriv->device, (size_t) SNDCTL_DSP_SYNC, NULL) < 0) {
lsx_fail_errno(ft,SOX_EOF,"Unable to sync dsp");
return (SOX_EOF);
}
if (ft->mode == 'r') {
pPriv->cOutput = 0;
pPriv->pOutput = NULL;
} else {
size_t cbOutput = sox_globals.bufsiz;
pPriv->cOutput = cbOutput >> pPriv->sample_shift;
pPriv->pOutput = lsx_malloc(cbOutput);
}
return(SOX_SUCCESS);
}
static int ossstop(sox_format_t* ft)
{
priv_t* pPriv = (priv_t*)ft->priv;
if (pPriv->device >= 0) {
close(pPriv->device);
}
if (pPriv->pOutput) {
free(pPriv->pOutput);
}
return SOX_SUCCESS;
}
static size_t ossread(sox_format_t* ft, sox_sample_t* pOutput, size_t cOutput)
{
priv_t* pPriv = (priv_t*)ft->priv;
char* pbOutput = (char*)pOutput;
size_t cbOutputLeft = cOutput << pPriv->sample_shift;
size_t i, cRead;
int cbRead;
SOX_SAMPLE_LOCALS;
LSX_USE_VAR(sox_macro_temp_double);
while (cbOutputLeft) {
cbRead = read(pPriv->device, pbOutput, cbOutputLeft);
if (cbRead <= 0) {
if (cbRead < 0) {
lsx_fail_errno(ft, errno, "Error reading from device");
return 0;
}
break;
}
cbOutputLeft -= cbRead;
pbOutput += cbRead;
}
/* Convert in-place (backwards) */
cRead = cOutput - (cbOutputLeft >> pPriv->sample_shift);
if (ft->encoding.reverse_bytes) {
switch (pPriv->sample_shift)
{
case 0:
for (i = cRead; i != 0; i--) {
pOutput[i - 1] = SOX_UNSIGNED_8BIT_TO_SAMPLE(
((sox_uint8_t*)pOutput)[i - 1],
dummy);
}
break;
case 1:
for (i = cRead; i != 0; i--) {
pOutput[i - 1] = SOX_SIGNED_16BIT_TO_SAMPLE(
lsx_swapw(((sox_int16_t*)pOutput)[i - 1]),
dummy);
}
break;
case 2:
for (i = cRead; i != 0; i--) {
pOutput[i - 1] = SOX_SIGNED_32BIT_TO_SAMPLE(
lsx_swapdw(((sox_int32_t*)pOutput)[i - 1]),
dummy);
}
break;
}
} else {
switch (pPriv->sample_shift)
{
case 0:
for (i = cRead; i != 0; i--) {
pOutput[i - 1] = SOX_UNSIGNED_8BIT_TO_SAMPLE(
((sox_uint8_t*)pOutput)[i - 1],
dummy);
}
break;
case 1:
for (i = cRead; i != 0; i--) {
pOutput[i - 1] = SOX_SIGNED_16BIT_TO_SAMPLE(
((sox_int16_t*)pOutput)[i - 1],
dummy);
}
break;
case 2:
for (i = cRead; i != 0; i--) {
pOutput[i - 1] = SOX_SIGNED_32BIT_TO_SAMPLE(
((sox_int32_t*)pOutput)[i - 1],
dummy);
}
break;
}
}
return cRead;
}
static size_t osswrite(
sox_format_t* ft,
const sox_sample_t* pInput,
size_t cInput)
{
priv_t* pPriv = (priv_t*)ft->priv;
size_t cInputRemaining = cInput;
unsigned cClips = 0;
SOX_SAMPLE_LOCALS;
while (cInputRemaining) {
size_t cStride;
size_t i;
size_t cbStride;
int cbWritten;
cStride = cInputRemaining;
if (cStride > pPriv->cOutput) {
cStride = pPriv->cOutput;
}
if (ft->encoding.reverse_bytes)
{
switch (pPriv->sample_shift)
{
case 0:
for (i = 0; i != cStride; i++) {
((sox_uint8_t*)pPriv->pOutput)[i] =
SOX_SAMPLE_TO_UNSIGNED_8BIT(pInput[i], cClips);
}
break;
case 1:
for (i = 0; i != cStride; i++) {
sox_int16_t s16 = SOX_SAMPLE_TO_SIGNED_16BIT(pInput[i], cClips);
((sox_int16_t*)pPriv->pOutput)[i] = lsx_swapw(s16);
}
break;
case 2:
for (i = 0; i != cStride; i++) {
((sox_int32_t*)pPriv->pOutput)[i] =
lsx_swapdw(SOX_SAMPLE_TO_SIGNED_32BIT(pInput[i], cClips));
}
break;
}
} else {
switch (pPriv->sample_shift)
{
case 0:
for (i = 0; i != cStride; i++) {
((sox_uint8_t*)pPriv->pOutput)[i] =
SOX_SAMPLE_TO_UNSIGNED_8BIT(pInput[i], cClips);
}
break;
case 1:
for (i = 0; i != cStride; i++) {
((sox_int16_t*)pPriv->pOutput)[i] =
SOX_SAMPLE_TO_SIGNED_16BIT(pInput[i], cClips);
}
break;
case 2:
for (i = 0; i != cStride; i++) {
((sox_int32_t*)pPriv->pOutput)[i] =
SOX_SAMPLE_TO_SIGNED_32BIT(pInput[i], cClips);
}
break;
}
}
cbStride = cStride << pPriv->sample_shift;
i = 0;
do {
cbWritten = write(pPriv->device, &pPriv->pOutput[i], cbStride - i);
i += cbWritten;
if (cbWritten <= 0) {
lsx_fail_errno(ft, errno, "Error writing to device");
return 0;
}
} while (i != cbStride);
cInputRemaining -= cStride;
pInput += cStride;
}
return cInput;
}
LSX_FORMAT_HANDLER(oss)
{
static char const* const names[] = {"ossdsp", "oss", NULL};
static unsigned const write_encodings[] = {
SOX_ENCODING_SIGN2, 32, 16, 0,
SOX_ENCODING_UNSIGNED, 8, 0,
0};
static sox_format_handler_t const handler = {SOX_LIB_VERSION_CODE,
"Open Sound System device driver for unix-like systems",
names, SOX_FILE_DEVICE | SOX_FILE_NOSTDIO,
ossinit, ossread, ossstop,
ossinit, osswrite, ossstop,
NULL, write_encodings, NULL, sizeof(priv_t)
};
return &handler;
}