xref: /csrg-svn/lib/libc/net/getnetent.c (revision 8324)
1 /*	getnetent.c	4.2	82/10/05	*/
2 
3 #include <stdio.h>
4 #include <sys/socket.h>
5 #include <netdb.h>
6 #include <ctype.h>
7 
8 #define	MAXALIASES	35
9 
10 static char *NETDB = "/usr/lib/networks";
11 static FILE *netf = NULL;
12 static char line[BUFSIZ+1];
13 static struct netent net;
14 static char *net_aliases[MAXALIASES];
15 static int stayopen = 0;
16 static char *any();
17 
18 setnetent(f)
19 	int f;
20 {
21 	if (netf == NULL)
22 		netf = fopen(NETDB, "r" );
23 	else
24 		rewind(netf);
25 	stayopen |= f;
26 }
27 
28 endnetent()
29 {
30 	if (netf && !stayopen) {
31 		fclose(netf);
32 		netf = NULL;
33 	}
34 }
35 
36 struct netent *
37 getnetent()
38 {
39 	char *p;
40 	register char *cp, **q;
41 
42 	if (netf == NULL && (netf = fopen(NETDB, "r" )) == NULL)
43 		return (NULL);
44 again:
45 	p = fgets(line, BUFSIZ, netf);
46 	if (p == NULL)
47 		return (NULL);
48 	if (*p == '#')
49 		goto again;
50 	cp = any(p, "#\n");
51 	if (cp == NULL)
52 		goto again;
53 	*cp = '\0';
54 	net.n_name = p;
55 	cp = any(p, " \t");
56 	if (cp == NULL)
57 		goto again;
58 	*cp++ = '\0';
59 	while (*cp == ' ' || *cp == '\t')
60 		cp++;
61 	p = any(cp, " \t");
62 	if (p != NULL)
63 		*p++ = '\0';
64 	net.n_net = inet_addr(cp);
65 	net.n_aliases = net_aliases;
66 	q = net_aliases, cp = p;
67 	while (*cp) {
68 		if (*cp == ' ' || *cp == '\t') {
69 			cp++;
70 			continue;
71 		}
72 		if (q < &net_aliases[MAXALIASES - 1])
73 			*q++ = cp;
74 		cp = any(cp, " \t");
75 		if (*cp != NULL)
76 			*cp++ = '\0';
77 	}
78 	*q = NULL;
79 	return (&net);
80 }
81 
82 static char *
83 any(cp, match)
84 	register char *cp;
85 	char *match;
86 {
87 	register char *mp, c;
88 
89 	while (c = *cp) {
90 		for (mp = match; *mp; mp++)
91 			if (*mp == c)
92 				return (cp);
93 		cp++;
94 	}
95 	return ((char *)0);
96 }
97