sds.c

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	unsigned int sample ;
	int 	k ;

	psds->read_block ++ ;
	psds->read_count = 0 ;

	if (psds->read_block * psds->samplesperblock > psds->frames)
	{	memset (psds->read_samples, 0, psds->samplesperblock * sizeof (int)) ;
		return 1 ;
		} ;

	if ((k = psf_fread (psds->read_data, 1, SDS_BLOCK_SIZE, psf)) != SDS_BLOCK_SIZE)
		psf_log_printf (psf, "*** Warning : short read (%d != %d).\n", k, SDS_BLOCK_SIZE) ;

	if (psds->read_data [0] != 0xF0)
	{	printf ("Error A : %02X\n", psds->read_data [0] & 0xFF) ;
		} ;

	checksum = psds->read_data [1] ;
	if (checksum != 0x7E)
	{	printf ("Error 1 : %02X\n", checksum & 0xFF) ;
		}

	for (k = 2 ; k < SDS_BLOCK_SIZE - 3 ; k ++)
		checksum ^= psds->read_data [k] ;

	checksum &= 0x7F ;

	if (checksum != psds->read_data [SDS_BLOCK_SIZE - 2])
	{	psf_log_printf (psf, "Block %d : checksum is %02X should be %02X\n", psds->read_data [4], checksum, psds->read_data [SDS_BLOCK_SIZE - 2]) ;
		} ;

	ucptr = psds->read_data + 5 ;
	for (k = 0 ; k < 120 ; k += 4)
	{	sample = (ucptr [k] << 25) + (ucptr [k + 1] << 18) + (ucptr [k + 2] << 11) + (ucptr [k + 3] << 4) ;
		psds->read_samples [k / 4] = (int) (sample - 0x80000000) ;
		} ;

	return 1 ;
} /* sds_4byte_read */


static sf_count_t
sds_read_s (SF_PRIVATE *psf, short *ptr, sf_count_t len)
{	SDS_PRIVATE	*psds ;
	int			*iptr ;
	int			k, bufferlen, readcount, count ;
	sf_count_t	total = 0 ;

	if (psf->fdata == NULL)
		return 0 ;
	psds = (SDS_PRIVATE*) psf->fdata ;

	iptr = psf->u.ibuf ;
	bufferlen = ARRAY_LEN (psf->u.ibuf) ;
	while (len > 0)
	{	readcount = (len >= bufferlen) ? bufferlen : len ;
		count = sds_read (psf, psds, iptr, readcount) ;
		for (k = 0 ; k < readcount ; k++)
			ptr [total + k] = iptr [k] >> 16 ;
		total += count ;
		len -= readcount ;
		} ;

	return total ;
} /* sds_read_s */

static sf_count_t
sds_read_i (SF_PRIVATE *psf, int *ptr, sf_count_t len)
{	SDS_PRIVATE *psds ;
	int			total ;

	if (psf->fdata == NULL)
		return 0 ;
	psds = (SDS_PRIVATE*) psf->fdata ;

	total = sds_read (psf, psds, ptr, len) ;

	return total ;
} /* sds_read_i */

static sf_count_t
sds_read_f (SF_PRIVATE *psf, float *ptr, sf_count_t len)
{	SDS_PRIVATE	*psds ;
	int			*iptr ;
	int			k, bufferlen, readcount, count ;
	sf_count_t	total = 0 ;
	float		normfact ;

	if (psf->fdata == NULL)
		return 0 ;
	psds = (SDS_PRIVATE*) psf->fdata ;

	if (psf->norm_float == SF_TRUE)
		normfact = 1.0 / 0x80000000 ;
	else
		normfact = 1.0 / (1 << psds->bitwidth) ;

	iptr = psf->u.ibuf ;
	bufferlen = ARRAY_LEN (psf->u.ibuf) ;
	while (len > 0)
	{	readcount = (len >= bufferlen) ? bufferlen : len ;
		count = sds_read (psf, psds, iptr, readcount) ;
		for (k = 0 ; k < readcount ; k++)
			ptr [total + k] = normfact * iptr [k] ;
		total += count ;
		len -= readcount ;
		} ;

	return total ;
} /* sds_read_f */

static sf_count_t
sds_read_d (SF_PRIVATE *psf, double *ptr, sf_count_t len)
{	SDS_PRIVATE	*psds ;
	int			*iptr ;
	int			k, bufferlen, readcount, count ;
	sf_count_t	total = 0 ;
	double		normfact ;

	if (psf->fdata == NULL)
		return 0 ;
	psds = (SDS_PRIVATE*) psf->fdata ;

	if (psf->norm_double == SF_TRUE)
		normfact = 1.0 / 0x80000000 ;
	else
		normfact = 1.0 / (1 << psds->bitwidth) ;

	iptr = psf->u.ibuf ;
	bufferlen = ARRAY_LEN (psf->u.ibuf) ;
	while (len > 0)
	{	readcount = (len >= bufferlen) ? bufferlen : len ;
		count = sds_read (psf, psds, iptr, readcount) ;
		for (k = 0 ; k < readcount ; k++)
			ptr [total + k] = normfact * iptr [k] ;
		total += count ;
		len -= readcount ;
		} ;

	return total ;
} /* sds_read_d */

static int
sds_read (SF_PRIVATE *psf, SDS_PRIVATE *psds, int *ptr, int len)
{	int	count, total = 0 ;

	while (total < len)
	{	if (psds->read_block * psds->samplesperblock >= psds->frames)
		{	memset (&(ptr [total]), 0, (len - total) * sizeof (int)) ;
			return total ;
			} ;

		if (psds->read_count >= psds->samplesperblock)
			psds->reader (psf, psds) ;

		count = (psds->samplesperblock - psds->read_count) ;
		count = (len - total > count) ? count : len - total ;

		memcpy (&(ptr [total]), &(psds->read_samples [psds->read_count]), count * sizeof (int)) ;
		total += count ;
		psds->read_count += count ;
		} ;

	return total ;
} /* sds_read */

/*==============================================================================
*/

static sf_count_t
sds_seek (SF_PRIVATE *psf, int mode, sf_count_t seek_from_start)
{	SDS_PRIVATE	*psds ;
	sf_count_t	file_offset ;
	int			newblock, newsample ;

	if ((psds = psf->fdata) == NULL)
	{	psf->error = SFE_INTERNAL ;
		return SF_SEEK_ERROR ;
		} ;

	if (psf->datalength < 0 || psf->dataoffset < 0)
	{	psf->error = SFE_BAD_SEEK ;
		return SF_SEEK_ERROR ;
		} ;

	if (seek_from_start < 0 || seek_from_start > psf->sf.frames)
	{	psf->error = SFE_BAD_SEEK ;
		return SF_SEEK_ERROR ;
		} ;

	if (mode == SFM_READ && psds->write_count > 0)
		psds->writer (psf, psds) ;

	newblock = seek_from_start / psds->samplesperblock ;
	newsample = seek_from_start % psds->samplesperblock ;

	switch (mode)
	{	case SFM_READ :
			if (newblock > psds->total_blocks)
			{	psf->error = SFE_BAD_SEEK ;
				return SF_SEEK_ERROR ;
				} ;

			file_offset = psf->dataoffset + newblock * SDS_BLOCK_SIZE ;

			if (psf_fseek (psf, file_offset, SEEK_SET) != file_offset)
			{	psf->error = SFE_SEEK_FAILED ;
				return SF_SEEK_ERROR ;
				} ;

			psds->read_block = newblock ;
			psds->reader (psf, psds) ;
			psds->read_count = newsample ;
			break ;

		case SFM_WRITE :
			if (newblock > psds->total_blocks)
			{	psf->error = SFE_BAD_SEEK ;
				return SF_SEEK_ERROR ;
				} ;

			file_offset = psf->dataoffset + newblock * SDS_BLOCK_SIZE ;

			if (psf_fseek (psf, file_offset, SEEK_SET) != file_offset)
			{	psf->error = SFE_SEEK_FAILED ;
				return SF_SEEK_ERROR ;
				} ;

			psds->write_block = newblock ;
			psds->reader (psf, psds) ;
			psds->write_count = newsample ;
			break ;

		default :
			psf->error = SFE_BAD_SEEK ;
			return SF_SEEK_ERROR ;
			break ;
		} ;

	return seek_from_start ;
} /* sds_seek */

/*==============================================================================
*/

static int
sds_2byte_write (SF_PRIVATE *psf, SDS_PRIVATE *psds)
{	unsigned char *ucptr, checksum ;
	unsigned int sample ;
	int 	k ;

	psds->write_data [0] = 0xF0 ;
	psds->write_data [1] = 0x7E ;
	psds->write_data [2] = 0 ;							/* Channel number */
	psds->write_data [3] = psds->write_block & 0x7F ;	/* Packet number */

	ucptr = psds->write_data + 5 ;
	for (k = 0 ; k < 120 ; k += 2)
	{	sample = psds->write_samples [k / 2] ;
		sample += 0x80000000 ;
		ucptr [k] = (sample >> 25) & 0x7F ;
		ucptr [k + 1] = (sample >> 18) & 0x7F ;
		} ;

	checksum = psds->write_data [1] ;
	for (k = 2 ; k < SDS_BLOCK_SIZE - 3 ; k ++)
		checksum ^= psds->write_data [k] ;
	checksum &= 0x7F ;

	psds->write_data [SDS_BLOCK_SIZE - 2] = checksum ;
	psds->write_data [SDS_BLOCK_SIZE - 1] = 0xF7 ;

	if ((k = psf_fwrite (psds->write_data, 1, SDS_BLOCK_SIZE, psf)) != SDS_BLOCK_SIZE)
		psf_log_printf (psf, "*** Warning : psf_fwrite (%d != %d).\n", k, SDS_BLOCK_SIZE) ;

	psds->write_block ++ ;
	psds->write_count = 0 ;

	if (psds->write_block > psds->total_blocks)
		psds->total_blocks = psds->write_block ;
	psds->frames = psds->total_blocks * psds->samplesperblock ;

	return 1 ;
} /* sds_2byte_write */

static int
sds_3byte_write (SF_PRIVATE *psf, SDS_PRIVATE *psds)
{	unsigned char *ucptr, checksum ;
	unsigned int sample ;
	int 	k ;

	psds->write_data [0] = 0xF0 ;
	psds->write_data [1] = 0x7E ;
	psds->write_data [2] = 0 ;							/* Channel number */
	psds->write_data [3] = psds->write_block & 0x7F ;	/* Packet number */

	ucptr = psds->write_data + 5 ;
	for (k = 0 ; k < 120 ; k += 3)
	{	sample = psds->write_samples [k / 3] ;
		sample += 0x80000000 ;
		ucptr [k] = (sample >> 25) & 0x7F ;
		ucptr [k + 1] = (sample >> 18) & 0x7F ;
		ucptr [k + 2] = (sample >> 11) & 0x7F ;
		} ;

	checksum = psds->write_data [1] ;
	for (k = 2 ; k < SDS_BLOCK_SIZE - 3 ; k ++)
		checksum ^= psds->write_data [k] ;
	checksum &= 0x7F ;

	psds->write_data [SDS_BLOCK_SIZE - 2] = checksum ;
	psds->write_data [SDS_BLOCK_SIZE - 1] = 0xF7 ;

	if ((k = psf_fwrite (psds->write_data, 1, SDS_BLOCK_SIZE, psf)) != SDS_BLOCK_SIZE)
		psf_log_printf (psf, "*** Warning : psf_fwrite (%d != %d).\n", k, SDS_BLOCK_SIZE) ;

	psds->write_block ++ ;
	psds->write_count = 0 ;

	if (psds->write_block > psds->total_blocks)
		psds->total_blocks = psds->write_block ;
	psds->frames = psds->total_blocks * psds->samplesperblock ;

	return 1 ;
} /* sds_3byte_write */

static int
sds_4byte_write (SF_PRIVATE *psf, SDS_PRIVATE *psds)
{	unsigned char *ucptr, checksum ;
	unsigned int sample ;
	int 	k ;

	psds->write_data [0] = 0xF0 ;
	psds->write_data [1] = 0x7E ;
	psds->write_data [2] = 0 ;							/* Channel number */
	psds->write_data [3] = psds->write_block & 0x7F ;	/* Packet number */

	ucptr = psds->write_data + 5 ;
	for (k = 0 ; k < 120 ; k += 4)
	{	sample = psds->write_samples [k / 4] ;
		sample += 0x80000000 ;
		ucptr [k] = (sample >> 25) & 0x7F ;
		ucptr [k + 1] = (sample >> 18) & 0x7F ;
		ucptr [k + 2] = (sample >> 11) & 0x7F ;
		ucptr [k + 3] = (sample >> 4) & 0x7F ;
		} ;

	checksum = psds->write_data [1] ;
	for (k = 2 ; k < SDS_BLOCK_SIZE - 3 ; k ++)
		checksum ^= psds->write_data [k] ;
	checksum &= 0x7F ;

	psds->write_data [SDS_BLOCK_SIZE - 2] = checksum ;
	psds->write_data [SDS_BLOCK_SIZE - 1] = 0xF7 ;

	if ((k = psf_fwrite (psds->write_data, 1, SDS_BLOCK_SIZE, psf)) != SDS_BLOCK_SIZE)
		psf_log_printf (psf, "*** Warning : psf_fwrite (%d != %d).\n", k, SDS_BLOCK_SIZE) ;

	psds->write_block ++ ;
	psds->write_count = 0 ;

	if (psds->write_block > psds->total_blocks)
		psds->total_blocks = psds->write_block ;
	psds->frames = psds->total_blocks * psds->samplesperblock ;

	return 1 ;
} /* sds_4byte_write */

static sf_count_t
sds_write_s (SF_PRIVATE *psf, short *ptr, sf_count_t len)
{	SDS_PRIVATE	*psds ;
	int			*iptr ;
	int			k, bufferlen, writecount, count ;
	sf_count_t	total = 0 ;

	if (psf->fdata == NULL)
		return 0 ;
	psds = (SDS_PRIVATE*) psf->fdata ;

	iptr = psf->u.ibuf ;
	bufferlen = ARRAY_LEN (psf->u.ibuf) ;
	while (len > 0)
	{	writecount = (len >= bufferlen) ? bufferlen : len ;
		for (k = 0 ; k < writecount ; k++)
			iptr [k] = ptr [total + k] << 16 ;
		count = sds_write (psf, psds, iptr, writecount) ;
		total += count ;
		len -= writecount ;
		} ;

	return total ;
} /* sds_write_s */

static sf_count_t
sds_write_i (SF_PRIVATE *psf, int *ptr, sf_count_t len)
{	SDS_PRIVATE *psds ;
	int			total ;

	if (psf->fdata == NULL)
		return 0 ;
	psds = (SDS_PRIVATE*) psf->fdata ;

	total = sds_write (psf, psds, ptr, len) ;

	return total ;
} /* sds_write_i */

static sf_count_t
sds_write_f (SF_PRIVATE *psf, float *ptr, sf_count_t len)
{	SDS_PRIVATE	*psds ;
	int			*iptr ;
	int			k, bufferlen, writecount, count ;
	sf_count_t	total = 0 ;
	float		normfact ;

	if (psf->fdata == NULL)
		return 0 ;
	psds = (SDS_PRIVATE*) psf->fdata ;

	if (psf->norm_float == SF_TRUE)
		normfact = 1.0 * 0x80000000 ;
	else
		normfact = 1.0 * (1 << psds->bitwidth) ;

	iptr = psf->u.ibuf ;
	bufferlen = ARRAY_LEN (psf->u.ibuf) ;
	while (len > 0)
	{	writecount = (len >= bufferlen) ? bufferlen : len ;
		for (k = 0 ; k < writecount ; k++)
			iptr [k] = normfact * ptr [total + k] ;
		count = sds_write (psf, psds, iptr, writecount) ;
		total += count ;
		len -= writecount ;
		} ;

	return total ;
} /* sds_write_f */

static sf_count_t
sds_write_d (SF_PRIVATE *psf, double *ptr, sf_count_t len)
{	SDS_PRIVATE	*psds ;
	int			*iptr ;
	int			k, bufferlen, writecount, count ;
	sf_count_t	total = 0 ;
	double		normfact ;

	if (psf->fdata == NULL)
		return 0 ;
	psds = (SDS_PRIVATE*) psf->fdata ;

	if (psf->norm_double == SF_TRUE)
		normfact = 1.0 * 0x80000000 ;
	else
		normfact = 1.0 * (1 << psds->bitwidth) ;

	iptr = psf->u.ibuf ;
	bufferlen = ARRAY_LEN (psf->u.ibuf) ;
	while (len > 0)
	{	writecount = (len >= bufferlen) ? bufferlen : len ;
		for (k = 0 ; k < writecount ; k++)
			iptr [k] = normfact * ptr [total + k] ;
		count = sds_write (psf, psds, iptr, writecount) ;
		total += count ;
		len -= writecount ;
		} ;

	return total ;
} /* sds_write_d */

static int
sds_write (SF_PRIVATE *psf, SDS_PRIVATE *psds, int *ptr, int len)
{	int	count, total = 0 ;

	while (total < len)
	{	count = psds->samplesperblock - psds->write_count ;
		if (count > len - total)
			count = len - total ;

		memcpy (&(psds->write_samples [psds->write_count]), &(ptr [total]), count * sizeof (int)) ;
		total += count ;
		psds->write_count += count ;

		if (psds->write_count >= psds->samplesperblock)
			psds->writer (psf, psds) ;
		} ;

	return total ;
} /* sds_write */

/*
** Do not edit or modify anything in this comment block.
** The arch-tag line is a file identity tag for the GNU Arch
** revision control system.
**
** arch-tag: d5d26aa3-368c-4ca6-bb85-377e5a2578cc
*/