xref: /csrg-svn/lib/libc/net/inet_network.c (revision 8362)
1*8362Ssam /*	@(#)inet_network.c	4.1	10/07/82	*/
2*8362Ssam 
3*8362Ssam #include <sys/types.h>
4*8362Ssam #include <ctype.h>
5*8362Ssam 
6*8362Ssam /*
7*8362Ssam  * Internet network address interpretation routine.
8*8362Ssam  * The library routines call this routine to interpret
9*8362Ssam  * network numbers.
10*8362Ssam  */
11*8362Ssam u_long
12*8362Ssam inet_network(cp)
13*8362Ssam 	register char *cp;
14*8362Ssam {
15*8362Ssam 	register u_long val, base, n;
16*8362Ssam 	register char c;
17*8362Ssam 	u_long parts[4], *pp = parts;
18*8362Ssam 
19*8362Ssam again:
20*8362Ssam 	val = 0; base = 10;
21*8362Ssam 	if (*cp == '0')
22*8362Ssam 		base = 8, cp++;
23*8362Ssam 	if (*cp == 'x' || *cp == 'X')
24*8362Ssam 		base = 16, cp++;
25*8362Ssam 	while (c = *cp) {
26*8362Ssam 		if (isdigit(c)) {
27*8362Ssam 			val = (val * base) + (c - '0');
28*8362Ssam 			cp++;
29*8362Ssam 			continue;
30*8362Ssam 		}
31*8362Ssam 		if (base == 16 && isxdigit(c)) {
32*8362Ssam 			val = (val << 4) + (c + 10 - (islower(c) ? 'a' : 'A'));
33*8362Ssam 			cp++;
34*8362Ssam 			continue;
35*8362Ssam 		}
36*8362Ssam 		break;
37*8362Ssam 	}
38*8362Ssam 	if (*cp == '.') {
39*8362Ssam 		if (pp >= parts + 4)
40*8362Ssam 			return (-1);
41*8362Ssam 		*pp++ = val, cp++;
42*8362Ssam 		goto again;
43*8362Ssam 	}
44*8362Ssam 	if (*cp && !isspace(*cp))
45*8362Ssam 		return (-1);
46*8362Ssam 	*pp++ = val;
47*8362Ssam 	n = pp - parts;
48*8362Ssam 	if (n > 4)
49*8362Ssam 		return (-1);
50*8362Ssam 	for (val = 0, i = 0; i < n; i++) {
51*8362Ssam 		val <<= 8;
52*8362Ssam 		val |= parts[i] & 0xff;
53*8362Ssam 	}
54*8362Ssam 	return (val);
55*8362Ssam }
56