wav.c

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						return error ;
					break ;

			case acid_MARKER :
					parsestage |= HAVE_other ;

					psf_binheader_readf (psf, "e4", &dword) ;
					psf_log_printf (psf, "acid : %u\n", dword) ;

					if ((error = wav_read_acid_chunk (psf, dword)))
						return error ;
					break ;

			case INFO_MARKER :
			case LIST_MARKER :
					parsestage |= HAVE_other ;

					if ((error = wav_subchunk_parse (psf, marker)) != 0)
						return error ;
					break ;

			case strc_MARKER : /* Multiple of 32 bytes. */

			case afsp_MARKER :
			case bext_MARKER :
			case clm_MARKER :
			case plst_MARKER :
			case DISP_MARKER :
			case MEXT_MARKER :
			case PAD_MARKER :
					parsestage |= HAVE_other ;

					psf_binheader_readf (psf, "e4", &dword) ;
					psf_log_printf (psf, "%M : %u\n", marker, dword) ;
					dword += (dword & 1) ;
					psf_binheader_readf (psf, "j", dword) ;
					break ;

			default :
					if (isprint ((marker >> 24) & 0xFF) && isprint ((marker >> 16) & 0xFF)
						&& isprint ((marker >> 8) & 0xFF) && isprint (marker & 0xFF))
					{	psf_binheader_readf (psf, "e4", &dword) ;
						psf_log_printf (psf, "*** %M : %d (unknown marker)\n", marker, dword) ;
						psf_binheader_readf (psf, "j", dword) ;
						break ;
						} ;
					if (psf_ftell (psf) & 0x03)
					{	psf_log_printf (psf, "  Unknown chunk marker at position %d. Resynching.\n", dword - 4) ;
						psf_binheader_readf (psf, "j", -3) ;
						break ;
						} ;
					psf_log_printf (psf, "*** Unknown chunk marker : %X. Exiting parser.\n", marker) ;
					done = SF_TRUE ;
					break ;
			} ;	/* switch (dword) */

		if (! psf->sf.seekable && (parsestage & HAVE_data))
			break ;

		if (psf_ftell (psf) >= psf->filelength - SIGNED_SIZEOF (dword))
		{	psf_log_printf (psf, "End\n") ;
			break ;
			} ;

		if (psf->logindex >= SIGNED_SIZEOF (psf->logbuffer) - 2)
			return SFE_LOG_OVERRUN ;
		} ; /* while (1) */

	if (! psf->dataoffset)
		return SFE_WAV_NO_DATA ;

	psf->endian = SF_ENDIAN_LITTLE ;		/* All WAV files are little endian. */

	psf_fseek (psf, psf->dataoffset, SEEK_SET) ;

	if (psf->is_pipe == 0)
	{	/*
		** Check for 'wvpk' at the start of the DATA section. Not able to
		** handle this.
		*/
		psf_binheader_readf (psf, "e4", &marker) ;
		if (marker == wvpk_MARKER || marker == OggS_MARKER)
			return SFE_WAV_WVPK_DATA ;
		} ;

	/* Seek to start of DATA section. */
	psf_fseek (psf, psf->dataoffset, SEEK_SET) ;

	psf->close = wav_close ;

	if (psf->blockwidth)
	{	if (psf->filelength - psf->dataoffset < psf->datalength)
			psf->sf.frames = (psf->filelength - psf->dataoffset) / psf->blockwidth ;
		else
			psf->sf.frames = psf->datalength / psf->blockwidth ;
		} ;

	switch (format)
	{

		case WAVE_FORMAT_EXTENSIBLE :
			/* compare GUIDs for known ones */
			if (wavex_write_guid_equal (&wav_fmt.ext.esf, &MSGUID_SUBTYPE_PCM))
				psf->sf.format = SF_FORMAT_WAVEX | u_bitwidth_to_subformat (psf->bytewidth * 8) ;
			else
			if (wavex_write_guid_equal (&wav_fmt.ext.esf, &MSGUID_SUBTYPE_MS_ADPCM))
			{	psf->sf.format = (SF_FORMAT_WAVEX | SF_FORMAT_MS_ADPCM) ;
				*blockalign = wav_fmt.msadpcm.blockalign ;
				*framesperblock = wav_fmt.msadpcm.samplesperblock ;
				}
			else if (wavex_write_guid_equal (&wav_fmt.ext.esf, &MSGUID_SUBTYPE_IEEE_FLOAT))
				psf->sf.format = SF_FORMAT_WAVEX | ((psf->bytewidth == 8) ? SF_FORMAT_DOUBLE : SF_FORMAT_FLOAT) ;
			else if (wavex_write_guid_equal (&wav_fmt.ext.esf, &MSGUID_SUBTYPE_ALAW))
				psf->sf.format = (SF_FORMAT_WAVEX | SF_FORMAT_ALAW) ;
			else if (wavex_write_guid_equal (&wav_fmt.ext.esf, &MSGUID_SUBTYPE_MULAW))
				psf->sf.format = (SF_FORMAT_WAVEX | SF_FORMAT_ULAW) ;
			else
				return SFE_UNIMPLEMENTED ;
			break ;

		case WAVE_FORMAT_PCM :
					psf->sf.format = SF_FORMAT_WAV | u_bitwidth_to_subformat (psf->bytewidth * 8) ;
					break ;

		case WAVE_FORMAT_MULAW :
		case IBM_FORMAT_MULAW :
					psf->sf.format = (SF_FORMAT_WAV | SF_FORMAT_ULAW) ;
					break ;

		case WAVE_FORMAT_ALAW :
		case IBM_FORMAT_ALAW :
					psf->sf.format = (SF_FORMAT_WAV | SF_FORMAT_ALAW) ;
					break ;

		case WAVE_FORMAT_MS_ADPCM :
					psf->sf.format = (SF_FORMAT_WAV | SF_FORMAT_MS_ADPCM) ;
					*blockalign = wav_fmt.msadpcm.blockalign ;
					*framesperblock = wav_fmt.msadpcm.samplesperblock ;
					break ;

		case WAVE_FORMAT_IMA_ADPCM :
					psf->sf.format = (SF_FORMAT_WAV | SF_FORMAT_IMA_ADPCM) ;
					*blockalign = wav_fmt.ima.blockalign ;
					*framesperblock = wav_fmt.ima.samplesperblock ;
					break ;

		case WAVE_FORMAT_GSM610 :
					psf->sf.format = (SF_FORMAT_WAV | SF_FORMAT_GSM610) ;
					break ;

		case WAVE_FORMAT_IEEE_FLOAT :
					psf->sf.format = SF_FORMAT_WAV ;
					psf->sf.format |= (psf->bytewidth == 8) ? SF_FORMAT_DOUBLE : SF_FORMAT_FLOAT ;
					break ;

		default : return SFE_UNIMPLEMENTED ;
		} ;

	return 0 ;
} /* wav_read_header */

static int
wav_write_header (SF_PRIVATE *psf, int calc_length)
{	sf_count_t	current ;
	int 		fmt_size, k, subformat, add_fact_chunk = SF_FALSE ;

	current = psf_ftell (psf) ;

	if (calc_length)
	{	psf->filelength = psf_get_filelen (psf) ;

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

		if (psf->dataend)
			psf->datalength -= psf->filelength - psf->dataend ;

		if (psf->bytewidth > 0)
			psf->sf.frames = psf->datalength / (psf->bytewidth * psf->sf.channels) ;
		} ;

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

	/* RIFF marker, length, WAVE and 'fmt ' markers. */
	if (psf->filelength < 8)
		psf_binheader_writef (psf, "etm8", RIFF_MARKER, 8) ;
	else
		psf_binheader_writef (psf, "etm8", RIFF_MARKER, psf->filelength - 8) ;

	/* WAVE and 'fmt ' markers. */
	psf_binheader_writef (psf, "emm", WAVE_MARKER, fmt_MARKER) ;

	subformat = psf->sf.format & SF_FORMAT_SUBMASK ;

	switch (subformat)
	{	case SF_FORMAT_PCM_U8 :
		case SF_FORMAT_PCM_16 :
		case SF_FORMAT_PCM_24 :
		case SF_FORMAT_PCM_32 :
					fmt_size = 2 + 2 + 4 + 4 + 2 + 2 ;

					/* fmt : format, channels, samplerate */
					psf_binheader_writef (psf, "e4224", fmt_size, WAVE_FORMAT_PCM, psf->sf.channels, psf->sf.samplerate) ;
					/*  fmt : bytespersec */
					psf_binheader_writef (psf, "e4", psf->sf.samplerate * psf->bytewidth * psf->sf.channels) ;
					/*  fmt : blockalign, bitwidth */
					psf_binheader_writef (psf, "e22", psf->bytewidth * psf->sf.channels, psf->bytewidth * 8) ;
					break ;

		case SF_FORMAT_FLOAT :
		case SF_FORMAT_DOUBLE :
					fmt_size = 2 + 2 + 4 + 4 + 2 + 2 ;

					/* fmt : format, channels, samplerate */
					psf_binheader_writef (psf, "e4224", fmt_size, WAVE_FORMAT_IEEE_FLOAT, psf->sf.channels, psf->sf.samplerate) ;
					/*  fmt : bytespersec */
					psf_binheader_writef (psf, "e4", psf->sf.samplerate * psf->bytewidth * psf->sf.channels) ;
					/*  fmt : blockalign, bitwidth */
					psf_binheader_writef (psf, "e22", psf->bytewidth * psf->sf.channels, psf->bytewidth * 8) ;

					add_fact_chunk = SF_TRUE ;
					break ;

		case SF_FORMAT_ULAW :
					fmt_size = 2 + 2 + 4 + 4 + 2 + 2 ;

					/* fmt : format, channels, samplerate */
					psf_binheader_writef (psf, "e4224", fmt_size, WAVE_FORMAT_MULAW, psf->sf.channels, psf->sf.samplerate) ;
					/*  fmt : bytespersec */
					psf_binheader_writef (psf, "e4", psf->sf.samplerate * psf->bytewidth * psf->sf.channels) ;
					/*  fmt : blockalign, bitwidth */
					psf_binheader_writef (psf, "e22", psf->bytewidth * psf->sf.channels, 8) ;

					add_fact_chunk = SF_TRUE ;
					break ;

		case SF_FORMAT_ALAW :
					fmt_size = 2 + 2 + 4 + 4 + 2 + 2 ;

					/* fmt : format, channels, samplerate */
					psf_binheader_writef (psf, "e4224", fmt_size, WAVE_FORMAT_ALAW, psf->sf.channels, psf->sf.samplerate) ;
					/*  fmt : bytespersec */
					psf_binheader_writef (psf, "e4", psf->sf.samplerate * psf->bytewidth * psf->sf.channels) ;
					/*  fmt : blockalign, bitwidth */
					psf_binheader_writef (psf, "e22", psf->bytewidth * psf->sf.channels, 8) ;

					add_fact_chunk = SF_TRUE ;
					break ;

		/* Lite remove start */
		case SF_FORMAT_IMA_ADPCM :
					{	int blockalign, framesperblock, bytespersec ;

						blockalign		= wav_w64_srate2blocksize (psf->sf.samplerate * psf->sf.channels) ;
						framesperblock	= 2 * (blockalign - 4 * psf->sf.channels) / psf->sf.channels + 1 ;
						bytespersec		= (psf->sf.samplerate * blockalign) / framesperblock ;

						/* fmt chunk. */
						fmt_size = 2 + 2 + 4 + 4 + 2 + 2 + 2 + 2 ;

						/* fmt : size, WAV format type, channels, samplerate, bytespersec */
						psf_binheader_writef (psf, "e42244", fmt_size, WAVE_FORMAT_IMA_ADPCM,
									psf->sf.channels, psf->sf.samplerate, bytespersec) ;

						/* fmt : blockalign, bitwidth, extrabytes, framesperblock. */
						psf_binheader_writef (psf, "e2222", blockalign, 4, 2, framesperblock) ;
						} ;

					add_fact_chunk = SF_TRUE ;
					break ;

		case SF_FORMAT_MS_ADPCM :
					{	int	blockalign, framesperblock, bytespersec, extrabytes ;

						blockalign		= wav_w64_srate2blocksize (psf->sf.samplerate * psf->sf.channels) ;
						framesperblock	= 2 + 2 * (blockalign - 7 * psf->sf.channels) / psf->sf.channels ;
						bytespersec		= (psf->sf.samplerate * blockalign) / framesperblock ;

						/* fmt chunk. */
						extrabytes	= 2 + 2 + MSADPCM_ADAPT_COEFF_COUNT * (2 + 2) ;
						fmt_size	= 2 + 2 + 4 + 4 + 2 + 2 + 2 + extrabytes ;

						/* fmt : size, WAV format type, channels. */
						psf_binheader_writef (psf, "e422", fmt_size, WAVE_FORMAT_MS_ADPCM, psf->sf.channels) ;

						/* fmt : samplerate, bytespersec. */
						psf_binheader_writef (psf, "e44", psf->sf.samplerate, bytespersec) ;

						/* fmt : blockalign, bitwidth, extrabytes, framesperblock. */
						psf_binheader_writef (psf, "e22222", blockalign, 4, extrabytes, framesperblock, 7) ;

						msadpcm_write_adapt_coeffs (psf) ;
						} ;

					add_fact_chunk = SF_TRUE ;
					break ;
		/* Lite remove end */

		case SF_FORMAT_GSM610 :
					{	int	blockalign, framesperblock, bytespersec ;

						blockalign		= WAV_W64_GSM610_BLOCKSIZE ;
						framesperblock	= WAV_W64_GSM610_SAMPLES ;
						bytespersec		= (psf->sf.samplerate * blockalign) / framesperblock ;

						/* fmt chunk. */
						fmt_size = 2 + 2 + 4 + 4 + 2 + 2 + 2 + 2 ;

						/* fmt : size, WAV format type, channels. */
						psf_binheader_writef (psf, "e422", fmt_size, WAVE_FORMAT_GSM610, psf->sf.channels) ;

						/* fmt : samplerate, bytespersec. */
						psf_binheader_writef (psf, "e44", psf->sf.samplerate, bytespersec) ;

						/* fmt : blockalign, bitwidth, extrabytes, framesperblock. */
						psf_binheader_writef (psf, "e2222", blockalign, 0, 2, framesperblock) ;
						} ;

					add_fact_chunk = SF_TRUE ;
					break ;

		default : 	return SFE_UNIMPLEMENTED ;
		} ;

	if (add_fact_chunk)
		psf_binheader_writef (psf, "etm48", fact_MARKER, 4, psf->sf.frames) ;

	if (psf->str_flags & SF_STR_LOCATE_START)
		wav_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) ;
		} ;

	psf_binheader_writef (psf, "etm8", data_MARKER, psf->datalength) ;
	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 ;
} /* wav_write_header */



static int
wavex_write_guid_equal (const EXT_SUBFORMAT * first, const EXT_SUBFORMAT * second)
{	return !memcmp (first, second, sizeof (EXT_SUBFORMAT)) ;
} /* wavex_write_guid_equal */


static void
wavex_write_guid (SF_PRIVATE *psf, const EXT_SUBFORMAT * subformat)
{
	psf_binheader_writef (psf, "e422b", subformat->esf_field1,
					subformat->esf_field2, subformat->esf_field3,
					subformat->esf_field4, 8) ;
} /* wavex_write_guid */


static int
wavex_write_header (SF_PRIVATE *psf, int calc_length)
{	sf_count_t	current ;
	int 		fmt_size, k, subformat, add_fact_chunk = SF_FALSE ;

	current = psf_ftell (psf) ;

	if (calc_length)
	{	psf->filelength = psf_get_filelen (psf) ;

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

		if (psf->dataend)
			psf->datalength -= psf->filelength - psf->dataend ;

		if (psf->bytewidth > 0)
			psf->sf.frames = psf->datalength / (psf->bytewidth * psf->sf.channels) ;
		} ;


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

	/* RIFF marker, length, WAVE and 'fmt ' markers. */
	if (psf->filelength < 8)
		psf_binheader_writef (psf, "etm8", RIFF_MARKER, 8) ;
	else
		psf_binheader_writef (psf, "etm8", RIFF_MARKER, psf->filelength - 8) ;

	/* WAVE and 'fmt ' markers. */
	psf_binheader_writef (psf, "emm", WAVE_MARKER, fmt_MARKER) ;

	subformat = psf->sf.format & SF_FORMAT_SUBMASK ;

	/* initial section (same for all, it appears) */
	switch (subformat)
	{	case SF_FORMAT_PCM_U8 :
		case SF_FORMAT_PCM_16 :
		case SF_FORMAT_PCM_24 :
		case SF_FORMAT_PCM_32 :
		case SF_FORMAT_FLOAT :
		case SF_FORMAT_DOUBLE :
		case SF_FORMAT_ULAW :
		case SF_FORMAT_ALAW :
			fmt_size = 2 + 2 + 4 + 4 + 2 + 2 + 2 + 2 + 4 + 4 + 2 + 2 + 8 ;

			/* fmt : format, channels, samplerate */
			psf_binheader_writef (psf, "e4224", fmt_size, WAVE_FORMAT_EXTENSIBLE, psf->sf.channels, psf->sf.samplerate) ;
			/*  fmt : bytespersec */
			psf_binheader_writef (psf, "e4", psf->sf.samplerate * psf->bytewidth * psf->sf.channels) ;
			/*  fmt : blockalign, bitwidth */
			psf_binheader_writef (psf, "e22", psf->bytewidth * psf->sf.channels, psf->bytewidth * 8) ;

			/* cbSize 22 is sizeof (WAVEFORMATEXTENSIBLE) - sizeof (WAVEFORMATEX) */
			psf_binheader_writef (psf, "e2", 22) ;

			/* wValidBitsPerSample, for our use same as bitwidth as we use it fully */
			psf_binheader_writef (psf, "e2", psf->bytewidth * 8) ;

			if (psf->sf.channels == 2)
				psf_binheader_writef (psf, "e4", 0x1 | 0x2 ) ;	/* dwChannelMask front left and right */
			else
				psf_binheader_writef (psf, "e4", 0) ;			/* dwChannelMask = 0 when in doubt */
			break ;

		case SF_FORMAT_MS_ADPCM : /* todo, GUID exists might have different header as per wav_write_header */
		default : return SFE_UNIMPLEMENTED ;
		} ;

	/* GUI section, different for each */

	switch (subformat)
	{	case SF_FORMAT_PCM_U8 :
		case SF_FORMAT_PCM_16 :
		case SF_FORMAT_PCM_24 :
		case SF_FORMAT_PCM_32 :
			wavex_write_guid (psf, &MSGUID_SUBTYPE_PCM) ;
			break ;

		case SF_FORMAT_FLOAT :
		case SF_FORMAT_DOUBLE :
			wavex_write_guid (psf, &MSGUID_SUBTYPE_IEEE_FLOAT) ;
			add_fact_chunk = SF_TRUE ;
			break ;

		case SF_FORMAT_ULAW :
			wavex_write_guid (psf, &MSGUID_SUBTYPE_MULAW) ;
			add_fact_chunk = SF_TRUE ;
			break ;