fcup-smsend[mult]: fix buglet in K&R C NULL pointer passing The only 100% safe way to pass a NULL pointer as a function argument in K&R C is to cast 0 to a pointer type; failing to do so may cause mysterious bugs (invalid stack frames or garbage in argument registers) on 64-bit machines. This issue has already been fixed in most of FC host tools, but I just found some missed spots: passing of NULL UDH to PDU encoding functions in fcup-smsend[mult] in the case of single (not concatenated) SMS.

/*
 * This library module contains some bits that help working with
 * alphabetic addresses.
 */

#include <sys/types.h>

u_char alpha_septets_to_digits[12] = {0, 2, 4, 6, 7, 9, 11, 13, 14, 16, 18, 20};

alpha_addr_valid(ndigits, sepp)
	unsigned ndigits, *sepp;
{
	unsigned n;

	for (n = 1; n <= 11; n++)
		if (alpha_septets_to_digits[n] == ndigits) {
			*sepp = n;
			return(1);
		}
	return(0);
}