view uptools/libcoding/gsm7_encode.c @ 926:6a0aa8d36d06

rvinterf backslash escape: introduce libprint The new helper function library named libprint is meant to replace the badly misnamed libg23, and will soon contain functions for printing all of the same kinds of GPF TST packets that are now handled in libg23. However, we are also moving safe_print_trace() from libasync to this new library, and changing it to emit our new backslash escape format.
author Mychaela Falconia <falcon@freecalypso.org>
date Tue, 23 May 2023 03:47:46 +0000
parents 061f8d75083d
children ec7e23d5151f
line wrap: on
line source

/*
 * 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;
		outcnt += n;
	}
	*outlenp = outcnt;
	return(0);
}