ref: 19032af10bf5b22ec31b327cbd3a590c6788e64c
dir: /src/sndrtool.c/
/*
* Sounder/Sndtool format handler: W V Neisius, February 1992
*
* June 28, 93: force output to mono.
*
* March 3, 1999 - cbagwell@sprynet.com
* Forced extra comment fields to zero.
*/
#include "st_i.h"
#include <math.h>
#include <string.h>
#include <stdio.h>
#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h> /* For SEEK_* defines if not found in stdio */
#endif
/* Private data used by writer */
typedef struct sndpriv {
st_size_t nsamples;
st_size_t dataStart;
} *snd_t;
#ifndef SEEK_CUR
#define SEEK_CUR 1
#endif
static void sndtwriteheader(ft_t ft, st_size_t nsamples);
int st_sndseek(ft_t ft, st_size_t offset)
{
st_size_t new_offset, channel_block, alignment;
snd_t snd = (snd_t ) ft->priv;
new_offset = offset * ft->info.size;
/* Make sure request aligns to a channel block (ie left+right) */
channel_block = ft->info.channels * ft->info.size;
alignment = new_offset % channel_block;
/* Most common mistaken is to compute something like
* "skip everthing upto and including this sample" so
* advance to next sample block in this case.
*/
if (alignment != 0)
new_offset += (channel_block - alignment);
new_offset += snd->dataStart;
return st_seeki(ft, new_offset, SEEK_SET);
}
/*======================================================================*/
/* SNDSTARTREAD */
/*======================================================================*/
int st_sndtstartread(ft_t ft)
{
snd_t snd = (snd_t ) ft->priv;
char buf[97];
unsigned short rate;
int rc;
/* Needed for rawread() */
rc = st_rawstartread(ft);
if (rc)
return rc;
/* sndt is in little endian format so
* swap bytes on big endian machines.
*/
if (ST_IS_BIGENDIAN)
{
ft->swap = ft->swap ? 0 : 1;
}
rate = 0;
/* determine file type */
/* if first 5 bytes == SOUND then this is probably a sndtool sound */
/* if first word (16 bits) == 0
and second word is between 4000 & 25000 then this is sounder sound */
/* otherwise, its probably raw, not handled here */
if (st_readbuf(ft, buf, 1, 2) != 2)
{
st_fail_errno(ft,errno,"SND: unexpected EOF");
return(ST_EOF);
}
if (strncmp(buf,"\0\0",2) == 0)
{
/* sounder */
st_readw(ft, &rate);
if (rate < 4000 || rate > 25000 )
{
st_fail_errno(ft,ST_EFMT,"SND: sample rate out of range");
return(ST_EOF);
}
st_seeki(ft, 4, SEEK_CUR);
}
else
{
/* sndtool ? */
st_readbuf(ft, &buf[2], 1, 6);
if (strncmp(buf,"SOUND",5))
{
st_fail_errno(ft,ST_EFMT,"SND: unrecognized SND format");
return(ST_EOF);
}
st_seeki(ft, 12, SEEK_CUR);
st_readw(ft, &rate);
st_seeki(ft, 6, SEEK_CUR);
if (st_reads(ft, buf, 96) == ST_EOF)
{
st_fail_errno(ft,ST_EHDR,"SND: unexpected EOF in SND header");
return(ST_EOF);
}
st_report("%s",buf);
}
ft->info.channels = 1;
ft->info.rate = rate;
ft->info.encoding = ST_ENCODING_UNSIGNED;
ft->info.size = ST_SIZE_BYTE;
snd->dataStart = st_tell(ft);
ft->length = st_filelength(ft) - snd->dataStart;
return (ST_SUCCESS);
}
/*======================================================================*/
/* SNDTSTARTWRITE */
/*======================================================================*/
int st_sndtstartwrite(ft_t ft)
{
snd_t p = (snd_t ) ft->priv;
int rc;
/* Needed for rawwrite() */
rc = st_rawstartwrite(ft);
if (rc)
return rc;
/* sndt is in little endian format so
* swap bytes on big endian machines
*/
if (ST_IS_BIGENDIAN)
{
ft->swap = ft->swap ? 0 : 1;
}
/* write header */
ft->info.channels = 1;
ft->info.encoding = ST_ENCODING_UNSIGNED;
ft->info.size = ST_SIZE_BYTE;
p->nsamples = 0;
sndtwriteheader(ft, 0);
return(ST_SUCCESS);
}
/*======================================================================*/
/* SNDRSTARTWRITE */
/*======================================================================*/
int st_sndrstartwrite(ft_t ft)
{
int rc;
/* Needed for rawread() */
rc = st_rawstartread(ft);
if (rc)
return rc;
/* sndr is in little endian format so
* swap bytes on big endian machines
*/
if (ST_IS_BIGENDIAN)
{
ft->swap = ft->swap ? 0 : 1;
}
/* write header */
ft->info.channels = 1;
ft->info.encoding = ST_ENCODING_UNSIGNED;
ft->info.size = ST_SIZE_BYTE;
/* sounder header */
st_writew (ft,0); /* sample size code */
st_writew (ft,(int) ft->info.rate); /* sample rate */
st_writew (ft,10); /* volume */
st_writew (ft,4); /* shift */
return(ST_SUCCESS);
}
/*======================================================================*/
/* SNDTWRITE */
/*======================================================================*/
st_ssize_t st_sndtwrite(ft_t ft, st_sample_t *buf, st_ssize_t len)
{
snd_t p = (snd_t ) ft->priv;
p->nsamples += len;
return st_rawwrite(ft, buf, len);
}
/*======================================================================*/
/* SNDTSTOPWRITE */
/*======================================================================*/
int st_sndtstopwrite(ft_t ft)
{
snd_t p = (snd_t ) ft->priv;
int rc;
/* Flush remaining buffer out */
rc = st_rawstopwrite(ft);
if (rc)
return rc;
/* fixup file sizes in header */
if (st_seeki(ft, 0L, 0) != 0){
st_fail_errno(ft,errno,"can't rewind output file to rewrite SND header");
return ST_EOF;
}
sndtwriteheader(ft, p->nsamples);
return(ST_SUCCESS);
}
/*======================================================================*/
/* SNDTWRITEHEADER */
/*======================================================================*/
static void sndtwriteheader(ft_t ft, st_size_t nsamples)
{
char name_buf[97];
/* sndtool header */
st_writes(ft, "SOUND"); /* magic */
st_writeb(ft, 0x1a);
st_writew (ft,0); /* hGSound */
st_writedw (ft,nsamples);
st_writedw (ft,0);
st_writedw (ft,nsamples);
st_writew (ft,(int) ft->info.rate);
st_writew (ft,0);
st_writew (ft,10);
st_writew (ft,4);
memset (name_buf, 0, 96);
sprintf (name_buf,"%.62s - File created by Sound Exchange",ft->filename);
st_writebuf(ft, name_buf, 1, 96);
}
/* Sndtool Sound File */
static char *sndtnames[] = {
"sndt",
NULL
};
const st_format_t st_snd_format = {
sndtnames,
NULL,
ST_FILE_STEREO | ST_FILE_SEEK,
st_sndtstartread,
st_rawread,
st_rawstopread,
st_sndtstartwrite,
st_sndtwrite,
st_sndtstopwrite,
st_sndseek
};
const st_format_t *st_snd_format_fn(void)
{
return &st_snd_format;
}