xref: /original-bsd/lib/libc/net/inet_network.c (revision 5cc71944)
1 /*
2  * Copyright (c) 1983 Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms are permitted
6  * provided that the above copyright notice and this paragraph are
7  * duplicated in all such forms and that any documentation,
8  * advertising materials, and other materials related to such
9  * distribution and use acknowledge that the software was developed
10  * by the University of California, Berkeley.  The name of the
11  * University may not be used to endorse or promote products derived
12  * from this software without specific prior written permission.
13  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
14  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
15  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
16  */
17 
18 #if defined(LIBC_SCCS) && !defined(lint)
19 static char sccsid[] = "@(#)inet_network.c	5.5 (Berkeley) 06/27/88";
20 #endif /* LIBC_SCCS and not lint */
21 
22 #include <sys/types.h>
23 #include <netinet/in.h>
24 #include <ctype.h>
25 
26 /*
27  * Internet network address interpretation routine.
28  * The library routines call this routine to interpret
29  * network numbers.
30  */
31 u_long
32 inet_network(cp)
33 	register char *cp;
34 {
35 	register u_long val, base, n;
36 	register char c;
37 	u_long parts[4], *pp = parts;
38 	register int i;
39 
40 again:
41 	val = 0; base = 10;
42 	if (*cp == '0')
43 		base = 8, cp++;
44 	if (*cp == 'x' || *cp == 'X')
45 		base = 16, cp++;
46 	while (c = *cp) {
47 		if (isdigit(c)) {
48 			val = (val * base) + (c - '0');
49 			cp++;
50 			continue;
51 		}
52 		if (base == 16 && isxdigit(c)) {
53 			val = (val << 4) + (c + 10 - (islower(c) ? 'a' : 'A'));
54 			cp++;
55 			continue;
56 		}
57 		break;
58 	}
59 	if (*cp == '.') {
60 		if (pp >= parts + 4)
61 			return (INADDR_NONE);
62 		*pp++ = val, cp++;
63 		goto again;
64 	}
65 	if (*cp && !isspace(*cp))
66 		return (INADDR_NONE);
67 	*pp++ = val;
68 	n = pp - parts;
69 	if (n > 4)
70 		return (INADDR_NONE);
71 	for (val = 0, i = 0; i < n; i++) {
72 		val <<= 8;
73 		val |= parts[i] & 0xff;
74 	}
75 	return (val);
76 }
77