view uptools/libcoding/gsm7_encode.c @ 356:dbeb4a5628f5

uptools/libcoding: implemented 8859-1 -> GSM7 encoding function
author Mychaela Falconia <falcon@freecalypso.org>
date Tue, 06 Feb 2018 20:18:43 +0000
parents
children 061f8d75083d
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/*
 * This library module implements the function for encoding from ISO 8859-1
 * into the GSM 7-bit default alphabet (03.38 or 23.038).
 */

#include <sys/types.h>

extern u_char gsm7_encode_table[256];

latin1_to_gsm7(inbuf, outbuf, outmax, outlenp)
	u_char *inbuf, *outbuf;
	unsigned outmax, *outlenp;
{
	u_char *ip = inbuf, *op = outbuf;
	unsigned outcnt = 0, c, n;

	while (c = *ip++) {
		c = gsm7_encode_table[c];
		if (c == 0xFF)
			return(-1);
		if (c & 0x80)
			n = 2;
		else
			n = 1;
		if (outcnt + n > outmax)
			return(-2);
		if (c & 0x80) {
			*op++ = 0x1B;
			*op++ = c & 0x7F;
		} else
			*op++ = c;
	}
	*outlenp = outcnt;
	return(0);
}