ref: 98c796a020ba9bed691702b524f41bfbd609cdde
dir: /common/libsndfile/src/nist.c/
/*
** Copyright (C) 1999-2001 Erik de Castro Lopo <erikd@zip.com.au>
**
** This program is free software; you can redistribute it and/or modify
** it under the terms of the GNU Lesser General Public License as published by
** the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
**
** You should have received a copy of the GNU Lesser General Public License
** along with this program; if not, write to the Free Software
** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
/*
** Some of the information used to read NIST files was gleaned from
** reading the code of Bill Schottstaedt's sndlib library
** ftp://ccrma-ftp.stanford.edu/pub/Lisp/sndlib.tar.gz
** However, no code from that package was used.
*/
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <ctype.h>
#include "sndfile.h"
#include "config.h"
#include "sfendian.h"
#include "common.h"
/*------------------------------------------------------------------------------
*/
#define NIST_HEADER_LENGTH 1024
/*------------------------------------------------------------------------------
** Private static functions.
*/
static int nist_close (SF_PRIVATE *psf) ;
static void nist_write_header (SF_PRIVATE *psf) ;
/*------------------------------------------------------------------------------
*/
int
nist_open_read (SF_PRIVATE *psf)
{ char *psf_header ;
int error ;
fseek (psf->file, 0, SEEK_SET) ;
psf_header = (char*) psf->header ;
fgets (psf_header, SF_HEADER_LEN, psf->file) ;
psf_log_printf (psf, psf_header) ;
if (strlen (psf_header) != 8 || strcmp (psf_header, "NIST_1A\n"))
return SFE_NIST_BAD_HEADER ;
fgets (psf_header, SF_HEADER_LEN, psf->file) ;
psf_log_printf (psf, psf_header) ;
if (strlen (psf_header) != 8 || atoi (psf_header) != 1024)
return SFE_NIST_BAD_HEADER ;
while (ftell (psf->file) < 1024 && !ferror (psf->file))
{ fgets (psf_header, SF_HEADER_LEN, psf->file) ;
psf_log_printf (psf, psf_header) ;
if (strstr (psf_header, "channel_count -i ") == psf_header)
sscanf (psf_header, "channel_count -i %u", &(psf->sf.channels)) ;
if (strstr (psf_header, "sample_count -i ") == psf_header)
sscanf (psf_header, "sample_count -i %u", &(psf->sf.samples)) ;
if (strstr (psf_header, "sample_rate -i ") == psf_header)
sscanf (psf_header, "sample_rate -i %u", &(psf->sf.samplerate)) ;
if (strstr (psf_header, "sample_n_bytes -i ") == psf_header)
sscanf (psf_header, "sample_n_bytes -i %u", &(psf->bytewidth)) ;
if (strstr (psf_header, "sample_sig_bits -i ") == psf_header)
sscanf (psf_header, "sample_sig_bits -i %u", &(psf->sf.pcmbitwidth)) ;
if (strstr (psf_header, "sample_byte_format -s") == psf_header)
{ int bytes ;
char str [8] = { 0, 0, 0, 0, 0, 0, 0, 0 } ;
sscanf (psf_header, "sample_byte_format -s%d %5s", &bytes, str) ;
if (bytes < 2 || bytes > 4)
return SFE_NIST_BAD_ENCODING ;
psf->bytewidth = bytes ;
if (strstr (str, "01") == str)
{ psf->endian = SF_ENDIAN_LITTLE ;
psf->sf.format = SF_FORMAT_NIST | SF_FORMAT_PCM_LE ;
}
else if (strstr (str, "10"))
{ psf->endian = SF_ENDIAN_BIG ;
psf->sf.format = SF_FORMAT_NIST | SF_FORMAT_PCM_BE ;
} ;
} ;
if (strstr (psf_header, "sample_coding -s") == psf_header)
return SFE_NIST_BAD_ENCODING ;
if (strstr (psf_header, "end_head") == psf_header)
break ;
} ;
psf->dataoffset = NIST_HEADER_LENGTH ;
psf->current = 0 ;
psf->sf.seekable = SF_TRUE ;
psf->sf.sections = 1 ;
psf->close = (func_close) nist_close ;
psf->blockwidth = psf->sf.channels * psf->bytewidth ;
psf->datalength = psf->filelength - psf->dataoffset ;
if ((error = pcm_read_init (psf)))
return error ;
fseek (psf->file, psf->dataoffset, SEEK_SET) ;
return 0 ;
} /* nist_open_read */
/*------------------------------------------------------------------------------
*/
int
nist_open_write (SF_PRIVATE *psf)
{ int subformat, error ;
if ((psf->sf.format & SF_FORMAT_TYPEMASK) != SF_FORMAT_NIST)
return SFE_BAD_OPEN_FORMAT ;
subformat = psf->sf.format & SF_FORMAT_SUBMASK ;
if (subformat == SF_FORMAT_PCM_BE)
psf->endian = SF_ENDIAN_BIG ;
else if (subformat == SF_FORMAT_PCM_LE)
psf->endian = SF_ENDIAN_LITTLE ;
else if (CPU_IS_BIG_ENDIAN && subformat == SF_FORMAT_PCM)
psf->endian = SF_ENDIAN_BIG ;
else if (CPU_IS_LITTLE_ENDIAN && subformat == SF_FORMAT_PCM)
psf->endian = SF_ENDIAN_LITTLE ;
else
return SFE_BAD_OPEN_FORMAT ;
psf->bytewidth = BITWIDTH2BYTES (psf->sf.pcmbitwidth) ;
psf->blockwidth = psf->bytewidth * psf->sf.channels ;
psf->dataoffset = NIST_HEADER_LENGTH ;
psf->datalength = psf->blockwidth * psf->sf.samples ;
psf->filelength = psf->datalength + psf->dataoffset ;
psf->error = 0 ;
if ((error = pcm_write_init (psf)))
return error ;
psf->close = (func_close) nist_close ;
psf->write_header = (func_wr_hdr) nist_write_header ;
nist_write_header (psf) ;
return 0 ;
} /* nist_open_write */
/*------------------------------------------------------------------------------
*/
static int
nist_close (SF_PRIVATE *psf)
{
if (psf->mode == SF_MODE_WRITE)
{ /* Now we know for certain the length of the file we can
** re-write correct values for the datasize header element.
*/
fseek (psf->file, 0, SEEK_END) ;
psf->filelength = ftell (psf->file) ;
psf->dataoffset = NIST_HEADER_LENGTH ;
psf->datalength = psf->filelength - psf->dataoffset ;
psf->sf.samples = psf->datalength / psf->blockwidth ;
nist_write_header (psf) ;
} ;
if (psf->fdata)
free (psf->fdata) ;
psf->fdata = NULL ;
return 0 ;
} /* nist_close */
/*=========================================================================
*/
static void
nist_write_header (SF_PRIVATE *psf)
{ char *end_str ;
if (psf->endian == SF_ENDIAN_BIG)
end_str = "10" ;
else if (psf->endian == SF_ENDIAN_LITTLE)
end_str = "01" ;
else
end_str = "error" ;
/* Clear the whole header. */
memset (psf->header, 0, sizeof (psf->header)) ;
psf_asciiheader_printf (psf, "NIST_1A\n 1024\n") ;
psf_asciiheader_printf (psf, "channel_count -i %d\n", psf->sf.channels) ;
psf_asciiheader_printf (psf, "sample_rate -i %d\n", psf->sf.samplerate) ;
psf_asciiheader_printf (psf, "sample_n_bytes -i %d\n", psf->bytewidth) ;
psf_asciiheader_printf (psf, "sample_byte_format -s%d %s\n", psf->bytewidth, end_str) ;
psf_asciiheader_printf (psf, "sample_sig_bits -i %d\n", psf->sf.pcmbitwidth) ;
psf_asciiheader_printf (psf, "sample_count -i %d\n", psf->sf.samples) ;
psf_asciiheader_printf (psf, "end_head\n") ;
fseek (psf->file, 0, SEEK_SET) ;
/* Zero fill to dataoffset. */
psf_binheader_writef (psf, "z", NIST_HEADER_LENGTH - psf->headindex) ;
fwrite (psf->header, psf->headindex, 1, psf->file) ;
return ;
} /* nist_write_header */
/*-
These were used to parse the sample_byte_format field but were discarded in favour
os a simpler method using strstr ().
static
int strictly_ascending (char *str)
{ int k ;
if (strlen (str) < 2)
return 0 ;
for (k = 1 ; str [k] ; k++)
if (str [k] != str [k-1] + 1)
return 0 ;
return 1 ;
} /+* strictly_ascending *+/
static int strictly_descending (char *str)
{ int k ;
if (strlen (str) < 2)
return 0 ;
for (k = 1 ; str [k] ; k++)
if (str [k] + 1 != str [k-1])
return 0 ;
return 1 ;
} /+* strictly_descending *+/
-*/