paf.c

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/*
** Copyright (C) 1999-2004 Erik de Castro Lopo <[e-mail]>
**
** 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.
*/

#include "config.h"

#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <string.h>
#include <ctype.h>

#include "sndfile.h"
#include "sfendian.h"
#include "float_cast.h"
#include "common.h"

/*------------------------------------------------------------------------------
** Macros to handle big/little endian issues.
*/

#define FAP_MARKER	(MAKE_MARKER ('f', 'a', 'p', ' '))
#define PAF_MARKER	(MAKE_MARKER (' ', 'p', 'a', 'f'))

/*------------------------------------------------------------------------------
** Other defines.
*/

#define	PAF_HEADER_LENGTH 			2048

#define	PAF24_SAMPLES_PER_BLOCK		10
#define	PAF24_BLOCK_SIZE			32

/*------------------------------------------------------------------------------
** Typedefs.
*/

typedef	struct
{	int	version ;
	int	endianness ;
    int	samplerate ;
    int	format ;
	int	channels ;
	int	source ;
} PAF_FMT ;

typedef struct
{	int				max_blocks, channels, samplesperblock, blocksize ;
	int				read_block, write_block, read_count, write_count ;
	sf_count_t		sample_count ;
	int				*samples ;
	unsigned char	*block ;
#if HAVE_FLEXIBLE_ARRAY
	int				data [] ; /* ISO C99 struct flexible array. */
#else
	int				data [1] ; /* This is a hack and may not work. */
#endif
} PAF24_PRIVATE ;

/*------------------------------------------------------------------------------
** Private static functions.
*/

static int paf24_init (SF_PRIVATE *psf) ;

static int	paf_read_header	(SF_PRIVATE *psf) ;
static int	paf_write_header (SF_PRIVATE *psf, int calc_length) ;

static sf_count_t paf24_read_s (SF_PRIVATE *psf, short *ptr, sf_count_t len) ;
static sf_count_t paf24_read_i (SF_PRIVATE *psf, int *ptr, sf_count_t len) ;
static sf_count_t paf24_read_f (SF_PRIVATE *psf, float *ptr, sf_count_t len) ;
static sf_count_t paf24_read_d (SF_PRIVATE *psf, double *ptr, sf_count_t len) ;

static sf_count_t paf24_write_s (SF_PRIVATE *psf, short *ptr, sf_count_t len) ;
static sf_count_t paf24_write_i (SF_PRIVATE *psf, int *ptr, sf_count_t len) ;
static sf_count_t paf24_write_f (SF_PRIVATE *psf, float *ptr, sf_count_t len) ;
static sf_count_t paf24_write_d (SF_PRIVATE *psf, double *ptr, sf_count_t len) ;

static sf_count_t paf24_seek (SF_PRIVATE *psf, int mode, sf_count_t offset) ;

enum
{	PAF_PCM_16 = 0,
	PAF_PCM_24 = 1,
	PAF_PCM_S8 = 2
} ;

/*------------------------------------------------------------------------------
** Public function.
*/

int
paf_open	(SF_PRIVATE *psf)
{	int		subformat, error, endian ;

 	psf->dataoffset = PAF_HEADER_LENGTH ;

	if (psf->mode == SFM_READ || (psf->mode == SFM_RDWR && psf->filelength > 0))
	{	if ((error = paf_read_header (psf)))
			return error ;
		} ;

	subformat = psf->sf.format & SF_FORMAT_SUBMASK ;

	if (psf->mode == SFM_WRITE || psf->mode == SFM_RDWR)
	{	if ((psf->sf.format & SF_FORMAT_TYPEMASK) != SF_FORMAT_PAF)
			return	SFE_BAD_OPEN_FORMAT ;

		endian = psf->sf.format & SF_FORMAT_ENDMASK ;

		/* PAF is by default big endian. */
		psf->endian = SF_ENDIAN_BIG ;

		if (endian == SF_ENDIAN_LITTLE || (CPU_IS_LITTLE_ENDIAN && (endian == SF_ENDIAN_CPU)))
			psf->endian = SF_ENDIAN_LITTLE ;

		if ((error = paf_write_header (psf, SF_FALSE)))
			return error ;

		psf->write_header = paf_write_header ;
		} ;

	switch (subformat)
	{	case SF_FORMAT_PCM_S8 :
					psf->bytewidth = 1 ;
					error = pcm_init (psf) ;
					break ;

		case SF_FORMAT_PCM_16 :
					psf->bytewidth = 2 ;
					error = pcm_init (psf) ;
					break ;

		case SF_FORMAT_PCM_24 :
					/* No bytewidth because of whacky 24 bit encoding. */
					error = paf24_init (psf) ;
					break ;

		default : return SFE_PAF_UNKNOWN_FORMAT ;
		} ;

	return error ;
} /* paf_open */

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

static int
paf_read_header	(SF_PRIVATE *psf)
{	PAF_FMT		paf_fmt ;
	int			marker ;

	psf_binheader_readf (psf, "pm", 0, &marker) ;

	psf_log_printf (psf, "Signature   : '%M'\n", marker) ;

	if (marker == PAF_MARKER)
	{	psf_binheader_readf (psf, "E444444", &(paf_fmt.version), &(paf_fmt.endianness),
			&(paf_fmt.samplerate), &(paf_fmt.format), &(paf_fmt.channels), &(paf_fmt.source)) ;
		}
	else if (marker == FAP_MARKER)
	{	psf_binheader_readf (psf, "e444444", &(paf_fmt.version), &(paf_fmt.endianness),
			&(paf_fmt.samplerate), &(paf_fmt.format), &(paf_fmt.channels), &(paf_fmt.source)) ;
		}
	else
		return SFE_PAF_NO_MARKER ;

	psf_log_printf (psf, "Version     : %d\n", paf_fmt.version) ;

	if (paf_fmt.version != 0)
	{	psf_log_printf (psf, "*** Bad version number. should be zero.\n") ;
		return SFE_PAF_VERSION ;
		} ;

	psf_log_printf (psf, "Sample Rate : %d\n", paf_fmt.samplerate) ;
	psf_log_printf (psf, "Channels    : %d\n", paf_fmt.channels) ;

	psf_log_printf (psf, "Endianness  : %d => ", paf_fmt.endianness) ;
	if (paf_fmt.endianness)
	{	psf_log_printf (psf, "Little\n", paf_fmt.endianness) ;
		psf->endian = SF_ENDIAN_LITTLE ;
		}
	else
	{	psf_log_printf (psf, "Big\n", paf_fmt.endianness) ;
		psf->endian = SF_ENDIAN_BIG ;
		} ;

	if (psf->filelength < PAF_HEADER_LENGTH)
		return SFE_PAF_SHORT_HEADER ;

	psf->datalength = psf->filelength - psf->dataoffset ;

	psf_binheader_readf (psf, "p", (int) psf->dataoffset) ;

	psf->sf.samplerate	= paf_fmt.samplerate ;
	psf->sf.channels 	= paf_fmt.channels ;

	/* Only fill in type major. */
	psf->sf.format = SF_FORMAT_PAF ;

	psf_log_printf (psf, "Format      : %d => ", paf_fmt.format) ;

	/* PAF is by default big endian. */
	psf->sf.format |= paf_fmt.endianness ? SF_ENDIAN_LITTLE : SF_ENDIAN_BIG ;

	switch (paf_fmt.format)
	{	case PAF_PCM_S8 :
					psf_log_printf (psf, "8 bit linear PCM\n") ;
					psf->bytewidth = 1 ;

					psf->sf.format |= SF_FORMAT_PCM_S8 ;

					psf->blockwidth = psf->bytewidth * psf->sf.channels ;
					psf->sf.frames = psf->datalength / psf->blockwidth ;
					break ;

		case PAF_PCM_16 :
					psf_log_printf (psf, "16 bit linear PCM\n") ;
					psf->bytewidth = 2 ;

					psf->sf.format |= SF_FORMAT_PCM_16 ;

					psf->blockwidth = psf->bytewidth * psf->sf.channels ;
					psf->sf.frames = psf->datalength / psf->blockwidth ;
					break ;

		case PAF_PCM_24 :
					psf_log_printf (psf, "24 bit linear PCM\n") ;
					psf->bytewidth = 3 ;

					psf->sf.format |= SF_FORMAT_PCM_24 ;

					psf->blockwidth = 0 ;
					psf->sf.frames = PAF24_SAMPLES_PER_BLOCK * psf->datalength /
											(PAF24_BLOCK_SIZE * psf->sf.channels) ;
					break ;

		default :	psf_log_printf (psf, "Unknown\n") ;
					return SFE_PAF_UNKNOWN_FORMAT ;
					break ;
		} ;

	psf_log_printf (psf, "Source      : %d => ", paf_fmt.source) ;

	switch (paf_fmt.source)
	{	case 1 : psf_log_printf (psf, "Analog Recording\n") ;
					break ;
		case 2 : psf_log_printf (psf, "Digital Transfer\n") ;
					break ;
		case 3 : psf_log_printf (psf, "Multi-track Mixdown\n") ;
					break ;
		case 5 : psf_log_printf (psf, "Audio Resulting From DSP Processing\n") ;
					break ;
		default : psf_log_printf (psf, "Unknown\n") ;
					break ;
		} ;

	return 0 ;
} /* paf_read_header */

static int
paf_write_header (SF_PRIVATE *psf, int calc_length)
{	int			paf_format ;

	/* PAF header already written so no need to re-write. */
	if (psf_ftell (psf) >= PAF_HEADER_LENGTH)
		return 0 ;

	psf->dataoffset = PAF_HEADER_LENGTH ;

	psf->dataoffset = PAF_HEADER_LENGTH ;

	/* Prevent compiler warning. */
	calc_length = calc_length ;

	switch (psf->sf.format & SF_FORMAT_SUBMASK)
	{	case SF_FORMAT_PCM_S8 :
					paf_format = PAF_PCM_S8 ;
					break ;

		case SF_FORMAT_PCM_16 :
					paf_format = PAF_PCM_16 ;
					break ;

		case SF_FORMAT_PCM_24 :
					paf_format = PAF_PCM_24 ;
					break ;

		default : return SFE_PAF_UNKNOWN_FORMAT ;
		} ;

	/* Reset the current header length to zero. */
	psf->header [0] = 0 ;
	psf->headindex = 0 ;

	if (psf->endian == SF_ENDIAN_BIG)
	{	/* Marker, version, endianness, samplerate */
		psf_binheader_writef (psf, "Em444", PAF_MARKER, 0, 0, psf->sf.samplerate) ;
		/* format, channels, source */
		psf_binheader_writef (psf, "E444", paf_format, psf->sf.channels, 0) ;
		}
	else if (psf->endian == SF_ENDIAN_LITTLE)
	{	/* Marker, version, endianness, samplerate */
		psf_binheader_writef (psf, "em444", FAP_MARKER, 0, 1, psf->sf.samplerate) ;
		/* format, channels, source */
		psf_binheader_writef (psf, "e444", paf_format, psf->sf.channels, 0) ;
		} ;

	/* Zero fill to dataoffset. */
	psf_binheader_writef (psf, "z", (size_t) (psf->dataoffset - psf->headindex)) ;

	psf_fwrite (psf->header, psf->headindex, 1, psf) ;

	return psf->error ;
} /* paf_write_header */

/*===============================================================================
**	24 bit PAF files have a really weird encoding.
**  For a mono file, 10 samples (each being 3 bytes) are packed into a 32 byte
**	block. The 8 ints in this 32 byte block are then endian swapped (as ints)
**	if necessary before being written to disk.
**  For a stereo file, blocks of 10 samples from the same channel are encoded
**  into 32 bytes as for the mono case. The 32 byte blocks are then interleaved
**	on disk.
**	Reading has to reverse the above process :-).
**	Weird!!!
**
**	The code below attempts to gain efficiency while maintaining readability.
*/

static int paf24_read_block (SF_PRIVATE *psf, PAF24_PRIVATE *ppaf24) ;
static int paf24_write_block (SF_PRIVATE *psf, PAF24_PRIVATE *ppaf24) ;
static int paf24_close (SF_PRIVATE *psf) ;


static int
paf24_init (SF_PRIVATE *psf)
{	PAF24_PRIVATE	*ppaf24 ;
	int	paf24size, max_blocks ;

	paf24size = sizeof (PAF24_PRIVATE) + psf->sf.channels *
					(PAF24_BLOCK_SIZE + PAF24_SAMPLES_PER_BLOCK * sizeof (int)) ;

	/*
	**	Not exatly sure why this needs to be here but the tests
	**	fail without it.
	*/
	psf->last_op = 0 ;

	if (! (psf->fdata = malloc (paf24size)))
		return SFE_MALLOC_FAILED ;

	ppaf24 = (PAF24_PRIVATE*) psf->fdata ;
	memset (ppaf24, 0, paf24size) ;

	ppaf24->channels	= psf->sf.channels ;
	ppaf24->samples		= ppaf24->data ;
	ppaf24->block		= (unsigned char*) (ppaf24->data + PAF24_SAMPLES_PER_BLOCK * ppaf24->channels) ;

	ppaf24->blocksize = PAF24_BLOCK_SIZE * ppaf24->channels ;
	ppaf24->samplesperblock = PAF24_SAMPLES_PER_BLOCK ;

	if (psf->mode == SFM_READ || psf->mode == SFM_RDWR)
	{	paf24_read_block (psf, ppaf24) ;	/* Read first block. */

		psf->read_short		= paf24_read_s ;
		psf->read_int		= paf24_read_i ;
		psf->read_float		= paf24_read_f ;
		psf->read_double	= paf24_read_d ;
		} ;

	if (psf->mode == SFM_WRITE || psf->mode == SFM_RDWR)
	{	psf->write_short	= paf24_write_s ;
		psf->write_int		= paf24_write_i ;
		psf->write_float	= paf24_write_f ;
		psf->write_double	= paf24_write_d ;
		} ;

	psf->seek	= paf24_seek ;
	psf->close	= paf24_close ;

	psf->filelength = psf_get_filelen (psf) ;
	psf->datalength = psf->filelength - psf->dataoffset ;

	if (psf->datalength % PAF24_BLOCK_SIZE)
	{	if (psf->mode == SFM_READ)
			psf_log_printf (psf, "*** Warning : file seems to be truncated.\n") ;
		max_blocks = psf->datalength / ppaf24->blocksize + 1 ;
		}
	else
		max_blocks = psf->datalength / ppaf24->blocksize ;

	ppaf24->read_block = 0 ;
	if (psf->mode == SFM_RDWR)
		ppaf24->write_block = max_blocks ;
	else
		ppaf24->write_block = 0 ;

	psf->sf.frames = ppaf24->samplesperblock * max_blocks ;
	ppaf24->sample_count = psf->sf.frames ;

	return 0 ;
} /* paf24_init */

static sf_count_t
paf24_seek (SF_PRIVATE *psf, int mode, sf_count_t offset)
{	PAF24_PRIVATE	*ppaf24 ;
	int				newblock, newsample ;

	if (psf->fdata == NULL)
	{	psf->error = SFE_INTERNAL ;