sd2_write_rsrc_fork (SF_PRIVATE *psf, int UNUSED (calc_length))
{	SD2_RSRC rsrc ;
	STR_RSRC str_rsrc [] =
	{	{ RSRC_STR, 1000, "_sample-size", "", 0 },
		{ RSRC_STR, 1001, "_sample-rate", "", 0 },
		{ RSRC_STR, 1002, "_channels", "", 0 },
		{ RSRC_BIN, 1000, "_Markers", "", 8 }
		} ;

	int k, str_offset, data_offset, next_str ;

	psf_use_rsrc (psf, SF_TRUE) ;

	memset (&rsrc, 0, sizeof (rsrc)) ;

	rsrc.sample_rate = psf->sf.samplerate ;
	rsrc.sample_size = psf->bytewidth ;
	rsrc.channels = psf->sf.channels ;

	rsrc.rsrc_data = psf->header ;
	rsrc.rsrc_len = sizeof (psf->header) ;
	memset (rsrc.rsrc_data, 0xea, rsrc.rsrc_len) ;

	snprintf (str_rsrc [0].value, sizeof (str_rsrc [0].value), "_%d", rsrc.sample_size) ;
	snprintf (str_rsrc [1].value, sizeof (str_rsrc [1].value), "_%d.000000", rsrc.sample_rate) ;
	snprintf (str_rsrc [2].value, sizeof (str_rsrc [2].value), "_%d", rsrc.channels) ;

	for (k = 0 ; k < ARRAY_LEN (str_rsrc) ; k++)
	{	if (str_rsrc [k].value_len == 0)
		{	str_rsrc [k].value_len = strlen (str_rsrc [k].value) ;
			str_rsrc [k].value [0] = str_rsrc [k].value_len - 1 ;
			} ;

		/* Turn name string into a pascal string. */
		str_rsrc [k].name [0] = strlen (str_rsrc [k].name) - 1 ;
		} ;

	rsrc.data_offset = 0x100 ;

	/*
	** Calculate data length :
	**		length of strings, plus the length of the sdML chunk.
	*/
	rsrc.data_length = 0 ;
	for (k = 0 ; k < ARRAY_LEN (str_rsrc) ; k++)
		rsrc.data_length += str_rsrc [k].value_len + 4 ;

	rsrc.map_offset = rsrc.data_offset + rsrc.data_length ;

	/* Very start of resource fork. */
	write_int (rsrc.rsrc_data, 0, rsrc.data_offset) ;
	write_int (rsrc.rsrc_data, 4, rsrc.map_offset) ;
	write_int (rsrc.rsrc_data, 8, rsrc.data_length) ;

	write_char (rsrc.rsrc_data, 0x30, strlen (psf->file.name.c)) ;
	write_str (rsrc.rsrc_data, 0x31, psf->file.name.c, strlen (psf->file.name.c)) ;

	write_short (rsrc.rsrc_data, 0x50, 0) ;
	write_marker (rsrc.rsrc_data, 0x52, Sd2f_MARKER) ;
	write_marker (rsrc.rsrc_data, 0x56, lsf1_MARKER) ;

	/* Very start of resource map. */
	write_int (rsrc.rsrc_data, rsrc.map_offset + 0, rsrc.data_offset) ;
	write_int (rsrc.rsrc_data, rsrc.map_offset + 4, rsrc.map_offset) ;
	write_int (rsrc.rsrc_data, rsrc.map_offset + 8, rsrc.data_length) ;

	/* These I don't currently understand. */
	if (1)
	{	write_char (rsrc.rsrc_data, rsrc.map_offset+ 16, 1) ;
		/* Next resource map. */
		write_int (rsrc.rsrc_data, rsrc.map_offset + 17, 0x12345678) ;
		/* File ref number. */
		write_short (rsrc.rsrc_data, rsrc.map_offset + 21, 0xabcd) ;
		/* Fork attributes. */
		write_short (rsrc.rsrc_data, rsrc.map_offset + 23, 0) ;
		} ;

	/* Resource type offset. */
	rsrc.type_offset = rsrc.map_offset + 30 ;
	write_short (rsrc.rsrc_data, rsrc.map_offset + 24, rsrc.type_offset - rsrc.map_offset - 2) ;

	/* Type index max. */
	rsrc.type_count = 2 ;
	write_short (rsrc.rsrc_data, rsrc.map_offset + 28, rsrc.type_count - 1) ;

	rsrc.item_offset = rsrc.type_offset + rsrc.type_count * 8 ;

	rsrc.str_count = ARRAY_LEN (str_rsrc) ;
	rsrc.string_offset = rsrc.item_offset + (rsrc.str_count + 1) * 12 - rsrc.map_offset ;
	write_short (rsrc.rsrc_data, rsrc.map_offset + 26, rsrc.string_offset) ;

	/* Write 'STR ' resource type. */
	rsrc.str_count = 3 ;
	write_marker (rsrc.rsrc_data, rsrc.type_offset, STR_MARKER) ;
	write_short (rsrc.rsrc_data, rsrc.type_offset + 4, rsrc.str_count - 1) ;
	write_short (rsrc.rsrc_data, rsrc.type_offset + 6, 0x12) ;

	/* Write 'sdML' resource type. */
	write_marker (rsrc.rsrc_data, rsrc.type_offset + 8, sdML_MARKER) ;
	write_short (rsrc.rsrc_data, rsrc.type_offset + 12, 0) ;
	write_short (rsrc.rsrc_data, rsrc.type_offset + 14, 0x36) ;

	str_offset = rsrc.map_offset + rsrc.string_offset ;
	next_str = 0 ;
	data_offset = rsrc.data_offset ;
	for (k = 0 ; k < ARRAY_LEN (str_rsrc) ; k++)
	{	write_str (rsrc.rsrc_data, str_offset, str_rsrc [k].name, strlen (str_rsrc [k].name)) ;

		write_short (rsrc.rsrc_data, rsrc.item_offset + k * 12, str_rsrc [k].id) ;
		write_short (rsrc.rsrc_data, rsrc.item_offset + k * 12 + 2, next_str) ;

		str_offset += strlen (str_rsrc [k].name) ;
		next_str += strlen (str_rsrc [k].name) ;

		write_int (rsrc.rsrc_data, rsrc.item_offset + k * 12 + 4, data_offset - rsrc.data_offset) ;

		write_int (rsrc.rsrc_data, data_offset, str_rsrc [k].value_len) ;
		write_str (rsrc.rsrc_data, data_offset + 4, str_rsrc [k].value, str_rsrc [k].value_len) ;
		data_offset += 4 + str_rsrc [k].value_len ;
		} ;

	/* Finally, calculate and set map length. */
	rsrc.map_length = str_offset - rsrc.map_offset ;
	write_int (rsrc.rsrc_data, 12, rsrc.map_length) ;
	write_int (rsrc.rsrc_data, rsrc.map_offset + 12, rsrc.map_length) ;

	rsrc.rsrc_len = rsrc.map_offset + rsrc.map_length ;

	psf_fwrite (rsrc.rsrc_data, rsrc.rsrc_len, 1, psf) ;

	psf_use_rsrc (psf, SF_FALSE) ;

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

	return 0 ;
} /* sd2_write_rsrc_fork */

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.