shithub: sox

ref: 51beed319b0d0ba2390b9284deb32fc79b7352e2
dir: /src/oss.c/

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#if	defined(OSS_PLAYER)
/*
 * 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 <unistd.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>
#include "st.h"

/* common r/w initialization code */
static int ossdspinit(ft)
ft_t ft;
{
    int sampletype, samplesize, dsp_stereo;
    int tmp, rc;

    if (ft->info.rate == 0.0) ft->info.rate = 8000;
    if (ft->info.size == -1) ft->info.size = ST_SIZE_BYTE;
    if (ft->info.size == ST_SIZE_BYTE) {
	sampletype = AFMT_U8;
	samplesize = 8;
	if (ft->info.encoding == -1)
	    ft->info.encoding = ST_ENCODING_UNSIGNED;
	if (ft->info.encoding != ST_ENCODING_UNSIGNED) {
	    st_report("OSS driver only supports unsigned with bytes");
	    st_report("Forcing to unsigned");
	    ft->info.encoding = ST_ENCODING_UNSIGNED;
	}
    }
    else if (ft->info.size == ST_SIZE_WORD) {
	sampletype = (ST_IS_BIGENDIAN) ? AFMT_S16_BE : AFMT_S16_LE;
	samplesize = 16;
	if (ft->info.encoding == -1)
	    ft->info.encoding = ST_ENCODING_SIGN2;
	if (ft->info.encoding != ST_ENCODING_SIGN2) {
	    st_report("OSS driver only supports signed with words");
	    st_report("Forcing to signed linear");
	    ft->info.encoding = ST_ENCODING_SIGN2;
	}
    }
    else {
	sampletype = (ST_IS_BIGENDIAN) ? AFMT_S16_BE : AFMT_S16_LE;
	samplesize = 16;
        ft->info.size = ST_SIZE_WORD;
	ft->info.encoding = ST_ENCODING_SIGN2;
	st_report("OSS driver only supports bytes and words");
	st_report("Forcing to signed linear word");
    }

    if (ft->info.channels == -1) ft->info.channels = 1;
    else if (ft->info.channels > 2) ft->info.channels = 2;

    if (ioctl(fileno(ft->fp), SNDCTL_DSP_RESET, 0) < 0)
    {
	st_fail_errno(ft,ST_EOF,"Unable to reset OSS driver.  Possibly accessing an invalid file/device");
	return(ST_EOF);
    }

    if (ioctl(fileno(ft->fp), SNDCTL_DSP_SYNC, NULL) < 0) {
	st_fail_errno(ft,ST_EOF,"Unable to sync dsp");
	return (ST_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->info.size = ST_SIZE_BYTE;
		ft->info.encoding = ST_ENCODING_UNSIGNED;
		st_report("OSS driver doesn't like signed words");
		st_report("Forcing to unsigned bytes");
		tmp = sampletype = AFMT_U8;
		samplesize = 8;
	    }
	    /* is 8-bit supported */
	    else if (samplesize == 8 && (tmp & AFMT_U8) == 0)
	    {
		ft->info.size = ST_SIZE_WORD;
		ft->info.encoding = ST_ENCODING_SIGN2;
		st_report("OSS driver doesn't like unsigned bytes");
		st_report("Forcing to signed words");
		sampletype = (ST_IS_BIGENDIAN) ? AFMT_S16_BE : AFMT_S16_LE;
		samplesize = 16;
	    }
	    /* determine which 16-bit format to use */
	    if (samplesize == 16)
	    {
	    	if ((tmp & sampletype) == 0)
		{
		    sampletype = (ST_IS_BIGENDIAN) ? AFMT_S16_LE : AFMT_S16_BE;
		    ft->swap = ft->swap ? 0 : 1;
		}
	    }
	}
	tmp = sampletype;
	rc = ioctl(fileno(ft->fp), SNDCTL_DSP_SETFMT, &tmp);
    }
    /* Give up and exit */
    if (rc < 0 || tmp != sampletype)
    {
	st_fail_errno(ft,ST_EOF,"Unable to set the sample size to %d", samplesize);
	return (ST_EOF);
    }

    if (ft->info.channels == 2) dsp_stereo = 1;
    else dsp_stereo = 0;

    tmp = dsp_stereo;
    if (ioctl(fileno(ft->fp), SNDCTL_DSP_STEREO, &tmp) < 0)
    {
	st_warn("Couldn't set to %s", dsp_stereo?  "stereo":"mono");
	dsp_stereo = 0;
    }

    if (tmp != dsp_stereo)
    {
	st_warn("Sound card appears to only support %d channels.  Overriding format\n", tmp+1);
	ft->info.channels = tmp + 1;
    }

    tmp = ft->info.rate;
    if (ioctl (fileno(ft->fp), SNDCTL_DSP_SPEED, &tmp) < 0 || 
    	ft->info.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 (ft->info.rate - tmp > (tmp * .01) || 
	    tmp - ft->info.rate > (tmp * .01)) {
	    st_warn("Unable to set audio speed to %d (set to %d)",
		     ft->info.rate, tmp);
	    ft->info.rate = tmp;
	}
    }

    /* Find out block size to use last because the driver could compute
     * its size based on specific rates/formats.
     */
    ft->file.size = 0;
    ioctl (fileno(ft->fp), SNDCTL_DSP_GETBLKSIZE, &ft->file.size);
    if (ft->file.size < 4 || ft->file.size > 65536) {
	    st_fail_errno(ft,ST_EOF,"Invalid audio buffer size %d", ft->file.size);
	    return (ST_EOF);
    }
    ft->file.count = 0;
    ft->file.pos = 0;
    ft->file.eof = 0;

    if ((ft->file.buf = malloc (ft->file.size)) == NULL) {
	st_fail_errno(ft,ST_EOF,"Unable to allocate input/output buffer of size %d", ft->file.size);
	return (ST_EOF);
    }

    /* Change to non-buffered I/O */
    setvbuf(ft->fp, NULL, _IONBF, sizeof(char) * ft->file.size);
    return(ST_SUCCESS);
}
/*
 * Do anything required before you start reading samples.
 * Read file header.
 *	Find out sampling rate,
 *	size and encoding of samples,
 *	mono/stereo/quad.
 */
int st_ossdspstartread(ft)
ft_t ft;
{
    int rc;
    rc = ossdspinit(ft);
    sigintreg(ft);	/* Prepare to catch SIGINT */
    return rc;
}

int st_ossdspstartwrite(ft)
ft_t ft;
{
    return ossdspinit(ft);
}
#endif