view uptools/libcoding/number_encode.c @ 407:19e5a3e2f9c0

fcup-settime: moved time() retrieval a little closer to the output A fundamental problem with all simple time transfer tools is that there is always some delay between the time retrieval on the source system and that transmitted time being set on the destination, and the resulting time on the destination system is off by that delay amount. This delay cannot be fully eliminated when working in a simple environment like ours, but we should make our best effort to minimize it. In the present case, moving the atinterf_init() call before the time() retrieval should make a teensy-tiny improvement.
author Mychaela Falconia <falcon@freecalypso.org>
date Sat, 11 Aug 2018 21:52:17 +0000
parents 7154a231e4b5
children
line wrap: on
line source

/*
 * This library module implements the function that parses SMS destination
 * addresses given by the user and encodes them into the GSM 03.40
 * TP-Destination-Address structure.
 */

#include <sys/types.h>
#include <ctype.h>
#include <stdlib.h>

digit_char_to_gsm(ch)
{
	switch (ch) {
	case '0':
	case '1':
	case '2':
	case '3':
	case '4':
	case '5':
	case '6':
	case '7':
	case '8':
	case '9':
		return (ch - '0');
	case '*':
		return 0xA;
	case '#':
		return 0xB;
	case 'a':
	case 'b':
	case 'c':
		return (ch - 'a' + 0xC);
	case 'A':
	case 'B':
	case 'C':
		return (ch - 'A' + 0xC);
	}
	return (-1);
}

parse_and_encode_dest_addr(input, outbuf)
	char *input;
	u_char *outbuf;
{
	char *cp, *endp;
	int d;
	u_char digits[20];
	unsigned n;

	cp = input;
	if (*cp == '+') {
		outbuf[1] = 0x91;
		cp++;
	} else
		outbuf[1] = 0x81;
	if (digit_char_to_gsm(*cp) < 0)
		return(-1);
	n = 0;
	while ((d = digit_char_to_gsm(*cp)) >= 0) {
		cp++;
		if (n >= 20)
			return(-1);
		digits[n++] = d;
	}
	outbuf[0] = n;
	while (n < 20)
		digits[n++] = 0xF;
	if (*cp == ',') {
		cp++;
		if (!isdigit(*cp))
			return(-1);
		outbuf[1] = strtoul(cp, &endp, 0);
		if (*endp)
			return(-1);
	} else if (*cp)
		return(-1);
	for (n = 0; n < 10; n++)
		outbuf[2+n] = (digits[n*2+1] << 4) | digits[n*2];
	return(0);
}