paf.c

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		return SF_SEEK_ERROR ;
		} ;

	ppaf24 = (PAF24_PRIVATE*) psf->fdata ;

	if (mode == SFM_READ && ppaf24->write_count > 0)
		paf24_write_block (psf, ppaf24) ;

	newblock	= offset / ppaf24->samplesperblock ;
	newsample	= offset % ppaf24->samplesperblock ;

	switch (mode)
	{	case SFM_READ :
				if (offset > ppaf24->read_block * ppaf24->samplesperblock + ppaf24->read_count)
				{	psf->error = SFE_BAD_SEEK ;
					return SF_SEEK_ERROR ;
					} ;

				if (psf->last_op == SFM_WRITE && ppaf24->write_count)
					paf24_write_block (psf, ppaf24) ;

				psf_fseek (psf, psf->dataoffset + newblock * ppaf24->blocksize, SEEK_SET) ;
				ppaf24->read_block = newblock ;
				paf24_read_block (psf, ppaf24) ;
				ppaf24->read_count = newsample ;
				break ;

		case SFM_WRITE :
				if (offset > ppaf24->sample_count)
				{	psf->error = SFE_BAD_SEEK ;
					return SF_SEEK_ERROR ;
					} ;

				if (psf->last_op == SFM_WRITE && ppaf24->write_count)
					paf24_write_block (psf, ppaf24) ;

				psf_fseek (psf, psf->dataoffset + newblock * ppaf24->blocksize, SEEK_SET) ;
				ppaf24->write_block = newblock ;
				paf24_read_block (psf, ppaf24) ;
				ppaf24->write_count = newsample ;
				break ;

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

	return newblock * ppaf24->samplesperblock + newsample ;
} /* paf24_seek */

static int
paf24_close (SF_PRIVATE *psf)
{	PAF24_PRIVATE *ppaf24 ;

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

	ppaf24 = (PAF24_PRIVATE*) psf->fdata ;

	if (psf->mode == SFM_WRITE || psf->mode == SFM_RDWR)
	{	if (ppaf24->write_count > 0)
			paf24_write_block (psf, ppaf24) ;
		} ;

	return 0 ;
} /* paf24_close */

/*---------------------------------------------------------------------------
*/
static int
paf24_read_block (SF_PRIVATE *psf, PAF24_PRIVATE *ppaf24)
{	int				k, channel ;
	unsigned char	*cptr ;

	ppaf24->read_block ++ ;
	ppaf24->read_count = 0 ;

	if (ppaf24->read_block * ppaf24->samplesperblock > ppaf24->sample_count)
	{	memset (ppaf24->samples, 0, ppaf24->samplesperblock * ppaf24->channels) ;
		return 1 ;
		} ;

	/* Read the block. */
	if ((k = psf_fread (ppaf24->block, 1, ppaf24->blocksize, psf)) != ppaf24->blocksize)
		psf_log_printf (psf, "*** Warning : short read (%d != %d).\n", k, ppaf24->blocksize) ;


	if (CPU_IS_LITTLE_ENDIAN)
	{	/* Do endian swapping if necessary. */
		if (psf->endian == SF_ENDIAN_BIG)
			endswap_int_array 	(ppaf24->data, 8 * ppaf24->channels) ;

		/* Unpack block. */
		for (k = 0 ; k < PAF24_SAMPLES_PER_BLOCK * ppaf24->channels ; k++)
		{	channel = k % ppaf24->channels ;
			cptr = ppaf24->block + PAF24_BLOCK_SIZE * channel + 3 * (k / ppaf24->channels) ;
			ppaf24->samples [k] = (cptr [0] << 8) | (cptr [1] << 16) | (cptr [2] << 24) ;
			} ;
		}
	else
	{	/* Do endian swapping if necessary. */
		if (psf->endian == SF_ENDIAN_BIG)
			endswap_int_array 	(ppaf24->data, 8 * ppaf24->channels) ;

		/* Unpack block. */
		for (k = 0 ; k < PAF24_SAMPLES_PER_BLOCK * ppaf24->channels ; k++)
		{	channel = k % ppaf24->channels ;
			cptr = ppaf24->block + PAF24_BLOCK_SIZE * channel + 3 * (k / ppaf24->channels) ;
			ppaf24->samples [k] = (cptr [0] << 8) | (cptr [1] << 16) | (cptr [2] << 24) ;
			} ;
		} ;

	return 1 ;
} /* paf24_read_block */

static int
paf24_read (SF_PRIVATE *psf, PAF24_PRIVATE *ppaf24, int *ptr, int len)
{	int	count, total = 0 ;

	while (total < len)
	{	if (ppaf24->read_block * ppaf24->samplesperblock >= ppaf24->sample_count)
		{	memset (&(ptr [total]), 0, (len - total) * sizeof (int)) ;
			return total ;
			} ;

		if (ppaf24->read_count >= ppaf24->samplesperblock)
			paf24_read_block (psf, ppaf24) ;

		count = (ppaf24->samplesperblock - ppaf24->read_count) * ppaf24->channels ;
		count = (len - total > count) ? count : len - total ;

		memcpy (&(ptr [total]), &(ppaf24->samples [ppaf24->read_count * ppaf24->channels]), count * sizeof (int)) ;
		total += count ;
		ppaf24->read_count += count / ppaf24->channels ;
		} ;

	return total ;
} /* paf24_read */

static sf_count_t
paf24_read_s (SF_PRIVATE *psf, short *ptr, sf_count_t len)
{	PAF24_PRIVATE 	*ppaf24 ;
	int				*iptr ;
	int				k, bufferlen, readcount, count ;
	sf_count_t		total = 0 ;

	if (psf->fdata == NULL)
		return 0 ;
	ppaf24 = (PAF24_PRIVATE*) psf->fdata ;

	iptr = psf->u.ibuf ;
	bufferlen = ARRAY_LEN (psf->u.ibuf) ;
	while (len > 0)
	{	readcount = (len >= bufferlen) ? bufferlen : len ;
		count = paf24_read (psf, ppaf24, iptr, readcount) ;
		for (k = 0 ; k < readcount ; k++)
			ptr [total + k] = iptr [k] >> 16 ;
		total += count ;
		len -= readcount ;
		} ;
	return total ;
} /* paf24_read_s */

static sf_count_t
paf24_read_i (SF_PRIVATE *psf, int *ptr, sf_count_t len)
{	PAF24_PRIVATE *ppaf24 ;
	int				total ;

	if (psf->fdata == NULL)
		return 0 ;
	ppaf24 = (PAF24_PRIVATE*) psf->fdata ;

	total = paf24_read (psf, ppaf24, ptr, len) ;

	return total ;
} /* paf24_read_i */

static sf_count_t
paf24_read_f (SF_PRIVATE *psf, float *ptr, sf_count_t len)
{	PAF24_PRIVATE 	*ppaf24 ;
	int				*iptr ;
	int				k, bufferlen, readcount, count ;
	sf_count_t		total = 0 ;
	float			normfact ;

	if (psf->fdata == NULL)
		return 0 ;
	ppaf24 = (PAF24_PRIVATE*) psf->fdata ;

	normfact = (psf->norm_float == SF_TRUE) ? (1.0 / 0x80000000) : (1.0 / 0x100) ;

	iptr = psf->u.ibuf ;
	bufferlen = ARRAY_LEN (psf->u.ibuf) ;
	while (len > 0)
	{	readcount = (len >= bufferlen) ? bufferlen : len ;
		count = paf24_read (psf, ppaf24, iptr, readcount) ;
		for (k = 0 ; k < readcount ; k++)
			ptr [total + k] = normfact * iptr [k] ;
		total += count ;
		len -= readcount ;
		} ;
	return total ;
} /* paf24_read_f */

static sf_count_t
paf24_read_d (SF_PRIVATE *psf, double *ptr, sf_count_t len)
{	PAF24_PRIVATE 	*ppaf24 ;
	int				*iptr ;
	int				k, bufferlen, readcount, count ;
	sf_count_t		total = 0 ;
	double 			normfact ;

	if (psf->fdata == NULL)
		return 0 ;
	ppaf24 = (PAF24_PRIVATE*) psf->fdata ;

	normfact = (psf->norm_double == SF_TRUE) ? (1.0 / 0x80000000) : (1.0 / 0x100) ;

	iptr = psf->u.ibuf ;
	bufferlen = ARRAY_LEN (psf->u.ibuf) ;
	while (len > 0)
	{	readcount = (len >= bufferlen) ? bufferlen : len ;
		count = paf24_read (psf, ppaf24, iptr, readcount) ;
		for (k = 0 ; k < readcount ; k++)
			ptr [total + k] = normfact * iptr [k] ;
		total += count ;
		len -= readcount ;
		} ;
	return total ;
} /* paf24_read_d */

/*---------------------------------------------------------------------------
*/

static int
paf24_write_block (SF_PRIVATE *psf, PAF24_PRIVATE *ppaf24)
{	int				k, nextsample, channel ;
	unsigned char	*cptr ;

	/* First pack block. */

	if (CPU_IS_LITTLE_ENDIAN)
	{	for (k = 0 ; k < PAF24_SAMPLES_PER_BLOCK * ppaf24->channels ; k++)
		{	channel = k % ppaf24->channels ;
			cptr = ppaf24->block + PAF24_BLOCK_SIZE * channel + 3 * (k / ppaf24->channels) ;
			nextsample = ppaf24->samples [k] >> 8 ;
			cptr [0] = nextsample ;
			cptr [1] = nextsample >> 8 ;
			cptr [2] = nextsample >> 16 ;
			} ;

		/* Do endian swapping if necessary. */
		if (psf->endian == SF_ENDIAN_BIG)
			endswap_int_array (ppaf24->data, 8 * ppaf24->channels) ;
		}
	else if (CPU_IS_BIG_ENDIAN)
	{	/* This is correct. */
		for (k = 0 ; k < PAF24_SAMPLES_PER_BLOCK * ppaf24->channels ; k++)
		{	channel = k % ppaf24->channels ;
			cptr = ppaf24->block + PAF24_BLOCK_SIZE * channel + 3 * (k / ppaf24->channels) ;
			nextsample = ppaf24->samples [k] >> 8 ;
			cptr [0] = nextsample ;
			cptr [1] = nextsample >> 8 ;
			cptr [2] = nextsample >> 16 ;
			} ;
		if (psf->endian == SF_ENDIAN_BIG)
			endswap_int_array (ppaf24->data, 8 * ppaf24->channels) ;
		} ;

	/* Write block to disk. */
	if ((k = psf_fwrite (ppaf24->block, 1, ppaf24->blocksize, psf)) != ppaf24->blocksize)
		psf_log_printf (psf, "*** Warning : short write (%d != %d).\n", k, ppaf24->blocksize) ;

	if (ppaf24->sample_count < ppaf24->write_block * ppaf24->samplesperblock + ppaf24->write_count)
		ppaf24->sample_count = ppaf24->write_block * ppaf24->samplesperblock + ppaf24->write_count ;

	if (ppaf24->write_count == ppaf24->samplesperblock)
	{	ppaf24->write_block ++ ;
		ppaf24->write_count = 0 ;
		} ;

	return 1 ;
} /* paf24_write_block */

static int
paf24_write (SF_PRIVATE *psf, PAF24_PRIVATE *ppaf24, int *ptr, int len)
{	int		count, total = 0 ;

	while (total < len)
	{	count = (ppaf24->samplesperblock - ppaf24->write_count) * ppaf24->channels ;

		if (count > len - total)
			count = len - total ;

		memcpy (&(ppaf24->samples [ppaf24->write_count * ppaf24->channels]), &(ptr [total]), count * sizeof (int)) ;
		total += count ;
		ppaf24->write_count += count / ppaf24->channels ;

		if (ppaf24->write_count >= ppaf24->samplesperblock)
			paf24_write_block (psf, ppaf24) ;
		} ;

	return total ;
} /* paf24_write */

static sf_count_t
paf24_write_s (SF_PRIVATE *psf, short *ptr, sf_count_t len)
{	PAF24_PRIVATE 	*ppaf24 ;
	int				*iptr ;
	int				k, bufferlen, writecount = 0, count ;
	sf_count_t		total = 0 ;

	if (psf->fdata == NULL)
		return 0 ;
	ppaf24 = (PAF24_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 = paf24_write (psf, ppaf24, iptr, writecount) ;
		total += count ;
		len -= writecount ;
		if (count != writecount)
			break ;
		} ;
	return total ;
} /* paf24_write_s */

static sf_count_t
paf24_write_i (SF_PRIVATE *psf, int *ptr, sf_count_t len)
{	PAF24_PRIVATE 	*ppaf24 ;
	int				writecount, count ;
	sf_count_t		total = 0 ;

	if (psf->fdata == NULL)
		return 0 ;
	ppaf24 = (PAF24_PRIVATE*) psf->fdata ;

	while (len > 0)
	{	writecount = (len > 0x10000000) ? 0x10000000 : (int) len ;

		count = paf24_write (psf, ppaf24, ptr, writecount) ;

		total += count ;
		len -= count ;
		if (count != writecount)
			break ;
		} ;

	return total ;
} /* paf24_write_i */

static sf_count_t
paf24_write_f (SF_PRIVATE *psf, float *ptr, sf_count_t len)
{	PAF24_PRIVATE 	*ppaf24 ;
	int				*iptr ;
	int				k, bufferlen, writecount = 0, count ;
	sf_count_t		total = 0 ;
	float			normfact ;

	if (psf->fdata == NULL)
		return 0 ;
	ppaf24 = (PAF24_PRIVATE*) psf->fdata ;

	normfact = (psf->norm_float == SF_TRUE) ? (1.0 * 0x7FFFFFFF) : (1.0 / 0x100) ;

	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] = lrintf (normfact * ptr [total + k]) ;
		count = paf24_write (psf, ppaf24, iptr, writecount) ;
		total += count ;
		len -= writecount ;
		if (count != writecount)
			break ;
		} ;

	return total ;
} /* paf24_write_f */

static sf_count_t
paf24_write_d (SF_PRIVATE *psf, double *ptr, sf_count_t len)
{	PAF24_PRIVATE 	*ppaf24 ;
	int				*iptr ;
	int				k, bufferlen, writecount = 0, count ;
	sf_count_t		total = 0 ;
	double			normfact ;

	if (psf->fdata == NULL)
		return 0 ;
	ppaf24 = (PAF24_PRIVATE*) psf->fdata ;

	normfact = (psf->norm_double == SF_TRUE) ? (1.0 * 0x7FFFFFFF) : (1.0 / 0x100) ;

	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] = lrint (normfact * ptr [total+k]) ;
		count = paf24_write (psf, ppaf24, iptr, writecount) ;
		total += count ;
		len -= writecount ;
		if (count != writecount)
			break ;
		} ;

	return total ;
} /* paf24_write_d */


/*
** Do not edit or modify anything in this comment block.
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** revision control system.
**
** arch-tag: 477a5308-451e-4bbd-bab4-fab6caa4e884
*/