aiff.c

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		** needs to be corrected for new data length. That means that we
		** only change the length fields of the FORM and SSND chunks;
		** everything else can be skipped over.
		*/

		/* First write new FORM chunk. */
		psf->headindex = 0 ;
		psf_fseek (psf, 0, SEEK_SET) ;

		psf_binheader_writef (psf, "Etm8", FORM_MARKER, psf->filelength - 8) ;
		psf_fwrite (psf->header, psf->headindex, 1, psf) ;

		/* Now write frame count field of COMM chunk header. */
		psf->headindex = 0 ;
		psf_fseek (psf, 22, SEEK_SET) ;

		psf_binheader_writef (psf, "Et8", psf->sf.frames) ;
		psf_fwrite (psf->header, psf->headindex, 1, psf) ;

		/* Now write new SSND chunk header. */
		psf->headindex = 0 ;
		psf_fseek (psf, psf->dataoffset - 16, SEEK_SET) ;

		psf_binheader_writef (psf, "Etm8", SSND_MARKER, psf->datalength + SIZEOF_SSND_CHUNK) ;
		psf_fwrite (psf->header, psf->headindex, 1, psf) ;

		if (current < psf->dataoffset)
			psf_fseek (psf, psf->dataoffset, SEEK_SET) ;
		else if (current > 0)
			psf_fseek (psf, current, SEEK_SET) ;

		return 0 ;
		} ;

	endian = psf->sf.format & SF_FORMAT_ENDMASK ;
	if (CPU_IS_LITTLE_ENDIAN && endian == SF_ENDIAN_CPU)
		endian = SF_ENDIAN_LITTLE ;

	/* Standard value here. */
	bit_width = psf->bytewidth * 8 ;
	comm_frames = (psf->sf.frames > 0xFFFFFFFF) ? 0xFFFFFFFF : psf->sf.frames ;

	switch (psf->sf.format & SF_FORMAT_SUBMASK)
	{	case SF_FORMAT_PCM_S8 :
		case SF_FORMAT_PCM_16 :
		case SF_FORMAT_PCM_24 :
		case SF_FORMAT_PCM_32 :
				switch (endian)
				{	case SF_ENDIAN_BIG :
							psf->endian = SF_ENDIAN_BIG ;
							comm_type = AIFC_MARKER ;
							comm_size = SIZEOF_AIFC_COMM ;
							comm_encoding = twos_MARKER ;
							break ;

					case SF_ENDIAN_LITTLE :
							psf->endian = SF_ENDIAN_LITTLE ;
							comm_type = AIFC_MARKER ;
							comm_size = SIZEOF_AIFC_COMM ;
							comm_encoding = sowt_MARKER ;
							break ;

					default : /* SF_ENDIAN_FILE */
							psf->endian = SF_ENDIAN_BIG ;
							comm_type = AIFF_MARKER ;
							comm_size = SIZEOF_AIFF_COMM ;
							comm_encoding = 0 ;
							break ;
					} ;
				break ;

		case SF_FORMAT_FLOAT :					/* Big endian floating point. */
				psf->endian = SF_ENDIAN_BIG ;
				comm_type = AIFC_MARKER ;
				comm_size = SIZEOF_AIFC_COMM ;
				comm_encoding = FL32_MARKER ;	/* Use 'FL32' because its easier to read. */
				break ;

		case SF_FORMAT_DOUBLE :					/* Big endian double precision floating point. */
				psf->endian = SF_ENDIAN_BIG ;
				comm_type = AIFC_MARKER ;
				comm_size = SIZEOF_AIFC_COMM ;
				comm_encoding = FL64_MARKER ;	/* Use 'FL64' because its easier to read. */
				break ;

		case SF_FORMAT_ULAW :
				psf->endian = SF_ENDIAN_BIG ;
				comm_type = AIFC_MARKER ;
				comm_size = SIZEOF_AIFC_COMM ;
				comm_encoding = ulaw_MARKER ;
				break ;

		case SF_FORMAT_ALAW :
				psf->endian = SF_ENDIAN_BIG ;
				comm_type = AIFC_MARKER ;
				comm_size = SIZEOF_AIFC_COMM ;
				comm_encoding = alaw_MARKER ;
				break ;

		case SF_FORMAT_PCM_U8 :
				psf->endian = SF_ENDIAN_BIG ;
				comm_type = AIFC_MARKER ;
				comm_size = SIZEOF_AIFC_COMM ;
				comm_encoding = raw_MARKER ;
				break ;

		case SF_FORMAT_DWVW_12 :
				psf->endian = SF_ENDIAN_BIG ;
				comm_type = AIFC_MARKER ;
				comm_size = SIZEOF_AIFC_COMM ;
				comm_encoding = DWVW_MARKER ;

				/* Override standard value here.*/
				bit_width = 12 ;
				break ;

		case SF_FORMAT_DWVW_16 :
				psf->endian = SF_ENDIAN_BIG ;
				comm_type = AIFC_MARKER ;
				comm_size = SIZEOF_AIFC_COMM ;
				comm_encoding = DWVW_MARKER ;

				/* Override standard value here.*/
				bit_width = 16 ;
				break ;

		case SF_FORMAT_DWVW_24 :
				psf->endian = SF_ENDIAN_BIG ;
				comm_type = AIFC_MARKER ;
				comm_size = SIZEOF_AIFC_COMM ;
				comm_encoding = DWVW_MARKER ;

				/* Override standard value here.*/
				bit_width = 24 ;
				break ;

		case SF_FORMAT_GSM610 :
				psf->endian = SF_ENDIAN_BIG ;
				comm_type = AIFC_MARKER ;
				comm_size = SIZEOF_AIFC_COMM ;
				comm_encoding = GSM_MARKER ;

				/* Override standard value here.*/
				bit_width = 16 ;
				break ;

		case SF_FORMAT_IMA_ADPCM :
				psf->endian = SF_ENDIAN_BIG ;
				comm_type = AIFC_MARKER ;
				comm_size = SIZEOF_AIFC_COMM ;
				comm_encoding = ima4_MARKER ;

				/* Override standard value here.*/
				bit_width = 16 ;
				comm_frames = psf->sf.frames / AIFC_IMA4_SAMPLES_PER_BLOCK ;
				break ;

		default : return SFE_BAD_OPEN_FORMAT ;
		} ;

	/* Reset the current header length to zero. */
	psf->header [0] = 0 ;
	psf->headindex = 0 ;
	psf_fseek (psf, 0, SEEK_SET) ;

	psf_binheader_writef (psf, "Etm8", FORM_MARKER, psf->filelength - 8) ;

	/* Write COMM chunk. */
	psf_binheader_writef (psf, "Emm4", comm_type, COMM_MARKER, comm_size) ;

	uint2tenbytefloat (psf->sf.samplerate, comm_sample_rate) ;

	psf_binheader_writef (psf, "Et242", psf->sf.channels, comm_frames, bit_width) ;
	psf_binheader_writef (psf, "b", comm_sample_rate, sizeof (comm_sample_rate)) ;

	/* AIFC chunks have some extra data. */
	if (comm_type == AIFC_MARKER)
		psf_binheader_writef (psf, "mb", comm_encoding, comm_zero_bytes, sizeof (comm_zero_bytes)) ;

	if (psf->str_flags & SF_STR_LOCATE_START)
		aiff_write_strings (psf, SF_STR_LOCATE_START) ;

	if (psf->has_peak && psf->peak_loc == SF_PEAK_START)
	{	psf_binheader_writef (psf, "Em4", PEAK_MARKER,
			sizeof (PEAK_CHUNK) + psf->sf.channels * sizeof (PEAK_POS)) ;
		psf_binheader_writef (psf, "E44", 1, time (NULL)) ;
		for (k = 0 ; k < psf->sf.channels ; k++)
			psf_binheader_writef (psf, "Ef4", psf->pchunk->peaks [k].value, psf->pchunk->peaks [k].position) ; /* XXXXX */
		} ;

	/* Write SSND chunk. */
	psf_binheader_writef (psf, "Etm844", SSND_MARKER, psf->datalength + SIZEOF_SSND_CHUNK, 0, 0) ;

	/* Header construction complete so write it out. */
	psf_fwrite (psf->header, psf->headindex, 1, psf) ;

	if (psf->error)
		return psf->error ;

	psf->dataoffset = psf->headindex ;

	if (current < psf->dataoffset)
		psf_fseek (psf, psf->dataoffset, SEEK_SET) ;
	else if (current > 0)
		psf_fseek (psf, current, SEEK_SET) ;

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

static int
aiff_write_tailer (SF_PRIVATE *psf)
{	int		k ;

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

	psf->dataend = psf_fseek (psf, 0, SEEK_END) ;

	if (psf->has_peak && psf->peak_loc == SF_PEAK_END)
	{	psf_binheader_writef (psf, "Em4", PEAK_MARKER,
			sizeof (PEAK_CHUNK) + psf->sf.channels * sizeof (PEAK_POS)) ;
		psf_binheader_writef (psf, "E44", 1, time (NULL)) ;
		for (k = 0 ; k < psf->sf.channels ; k++)
			psf_binheader_writef (psf, "Ef4", psf->pchunk->peaks [k].value, psf->pchunk->peaks [k].position) ; /* XXXXX */
		} ;

	if (psf->str_flags & SF_STR_LOCATE_END)
		aiff_write_strings (psf, SF_STR_LOCATE_END) ;

	/* Write the tailer. */
	if (psf->headindex)
		psf_fwrite (psf->header, psf->headindex, 1, psf) ;

	return 0 ;
} /* aiff_write_tailer */

static void
aiff_write_strings (SF_PRIVATE *psf, int location)
{	int	k ;

	for (k = 0 ; k < SF_MAX_STRINGS ; k++)
	{	if (psf->strings [k].type == 0)
			break ;

		if (psf->strings [k].flags != location)
			continue ;

		switch (psf->strings [k].type)
		{	case SF_STR_SOFTWARE :
				psf_binheader_writef (psf, "Ems", APPL_MARKER, psf->strings [k].str) ;
				break ;

			case SF_STR_TITLE :
				psf_binheader_writef (psf, "Ems", NAME_MARKER, psf->strings [k].str) ;
				break ;

			case SF_STR_COPYRIGHT :
				psf_binheader_writef (psf, "Ems", c_MARKER, psf->strings [k].str) ;
				break ;

			case SF_STR_ARTIST :
				psf_binheader_writef (psf, "Ems", AUTH_MARKER, psf->strings [k].str) ;
				break ;

			case SF_STR_COMMENT :
				psf_binheader_writef (psf, "Ems", ANNO_MARKER, psf->strings [k].str) ;
				break ;

			/*
			case SF_STR_DATE :
				psf_binheader_writef (psf, "Ems", ICRD_MARKER, psf->strings [k].str) ;
				break ;
			*/
			} ;
		} ;

	return ;
} /* aiff_write_strings */

static int
aiff_command (SF_PRIVATE *psf, int command, void *data, int datasize)
{
	/* Avoid compiler warnings. */
	psf = psf ;
	data = data ;
	datasize = datasize ;

	switch (command)
	{	default : break ;
		} ;

	return 0 ;
} /* aiff_command */

static const char*
get_loop_mode_str (short mode)
{	switch (mode)
	{	case 0 : return "none" ;
		case 1 : return "forward" ;
		case 2 : return "backward" ;
		} ;

	return "*** unknown" ;
} /* get_loop_mode_str */

/*==========================================================================================
**	Rough hack at converting from 80 bit IEEE float in AIFF header to an int and
**	back again. It assumes that all sample rates are between 1 and 800MHz, which
**	should be OK as other sound file formats use a 32 bit integer to store sample
**	rate.
**	There is another (probably better) version in the source code to the SoX but it
**	has a copyright which probably prevents it from being allowable as GPL/LGPL.
*/

static int
tenbytefloat2int (unsigned char *bytes)
{	int val = 3 ;

	if (bytes [0] & 0x80)	/* Negative number. */
		return 0 ;

	if (bytes [0] <= 0x3F)	/* Less than 1. */
		return 1 ;

	if (bytes [0] > 0x40)	/* Way too big. */
		return 0x4000000 ;

	if (bytes [0] == 0x40 && bytes [1] > 0x1C) /* Too big. */
		return 800000000 ;

	/* Ok, can handle it. */

	val = (bytes [2] << 23) | (bytes [3] << 15) | (bytes [4] << 7) | (bytes [5] >> 1) ;

	val >>= (29 - bytes [1]) ;

	return val ;
} /* tenbytefloat2int */

static void
uint2tenbytefloat (unsigned int num, unsigned char *bytes)
{	unsigned int mask = 0x40000000 ;
	int		count ;


	memset (bytes, 0, 10) ;

	if (num <= 1)
	{	bytes [0] = 0x3F ;
		bytes [1] = 0xFF ;
		bytes [2] = 0x80 ;
		return ;
		} ;

	bytes [0] = 0x40 ;

	if (num >= mask)
	{	bytes [1] = 0x1D ;
		return ;
		} ;

	for (count = 0 ; count <= 32 ; count ++)
	{	if (num & mask)
			break ;
		mask >>= 1 ;
		} ;

	num <<= count + 1 ;
	bytes [1] = 29 - count ;
	bytes [2] = (num >> 24) & 0xFF ;
	bytes [3] = (num >> 16) & 0xFF ;
	bytes [4] = (num >> 8) & 0xFF ;
	bytes [5] = num & 0xFF ;

} /* uint2tenbytefloat */

static int
aiff_read_basc_chunk (SF_PRIVATE * psf)
{	const char * type_str ;
	basc_CHUNK bc ;

	psf_binheader_readf (psf, "E442", &bc.version, &bc.numBeats, &bc.rootNote) ;
	psf_binheader_readf (psf, "E222", &bc.scaleType, &bc.sigNumerator, &bc.sigDenominator) ;
	psf_binheader_readf (psf, "E2b", &bc.loopType, &bc.zero_bytes, SIZEOF_basc_CHUNK_PADDING) ;

	psf_log_printf (psf, "  Version ? : %u\n  Num Beats : %u\n  Root Note : 0x%x\n",
						bc.version, bc.numBeats, bc.rootNote) ;

	switch (bc.scaleType)
	{	case basc_SCALE_MINOR :
				type_str = "MINOR" ;
				break ;
		case basc_SCALE_MAJOR :
				type_str = "MAJOR" ;
				break ;
		case basc_SCALE_NEITHER :
				type_str = "NEITHER" ;
				break ;
		case basc_SCALE_BOTH :
				type_str = "BOTH" ;
				break ;
		default :
				type_str = "!!WRONG!!" ;
				break ;
		} ;

	psf_log_printf (psf, 	"  ScaleType : 0x%x (%s)\n", bc.scaleType, type_str) ;
	psf_log_printf (psf, 	"  Time Sig  : %d/%d\n", bc.sigNumerator, bc.sigDenominator) ;

	switch (bc.loopType)
	{	case basc_TYPE_ONE_SHOT :
				type_str = "One Shot" ;
				break ;
		case basc_TYPE_LOOP :
				type_str = "Loop" ;
				break ;
		default:
				type_str = "!!WRONG!!" ;
				break ;
		} ;

	psf_log_printf (psf, "  Loop Type : 0x%x (%s)\n", bc.loopType, type_str) ;

	if ((psf->loop_info = calloc (1, sizeof (SF_LOOP_INFO))) == NULL)
		return SFE_MALLOC_FAILED ;

	psf->loop_info->time_sig_num	= bc.sigNumerator ;
	psf->loop_info->time_sig_den	= bc.sigDenominator ;
	psf->loop_info->loop_mode		= (bc.loopType == basc_TYPE_ONE_SHOT) ? SF_LOOP_NONE : SF_LOOP_FORWARD ;
	psf->loop_info->num_beats		= bc.numBeats ;

	/* Can always be recalculated from other known fields. */
	psf->loop_info->bpm = (1.0 / psf->sf.frames) * psf->sf.samplerate
							* ((bc.numBeats * 4.0) / bc.sigDenominator) * 60.0 ;
	psf->loop_info->root_key = bc.rootNote ;

	return 0 ;
} /* aiff_read_basc_chunk */

/*
** 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: 7dec56ca-d6f2-48cf-863b-a72e7e17a5d9
*/