xref: /csrg-svn/lib/libc/net/getnetent.c (revision 12691)
1 /*	getnetent.c	4.8	83/05/23	*/
2 
3 #include <stdio.h>
4 #include <sys/types.h>
5 #include <sys/socket.h>
6 #include <netdb.h>
7 #include <ctype.h>
8 
9 #define	MAXALIASES	35
10 
11 static char NETDB[] = "/etc/networks";
12 static FILE *netf = NULL;
13 static char line[BUFSIZ+1];
14 static struct netent net;
15 static char *net_aliases[MAXALIASES];
16 static int stayopen = 0;
17 static char *any();
18 
19 setnetent(f)
20 	int f;
21 {
22 	if (netf == NULL)
23 		netf = fopen(NETDB, "r" );
24 	else
25 		rewind(netf);
26 	stayopen |= f;
27 }
28 
29 endnetent()
30 {
31 	if (netf && !stayopen) {
32 		fclose(netf);
33 		netf = NULL;
34 	}
35 }
36 
37 struct netent *
38 getnetent()
39 {
40 	char *p;
41 	register char *cp, **q;
42 
43 	if (netf == NULL && (netf = fopen(NETDB, "r" )) == NULL)
44 		return (NULL);
45 again:
46 	p = fgets(line, BUFSIZ, netf);
47 	if (p == NULL)
48 		return (NULL);
49 	if (*p == '#')
50 		goto again;
51 	cp = any(p, "#\n");
52 	if (cp == NULL)
53 		goto again;
54 	*cp = '\0';
55 	net.n_name = p;
56 	cp = any(p, " \t");
57 	if (cp == NULL)
58 		goto again;
59 	*cp++ = '\0';
60 	while (*cp == ' ' || *cp == '\t')
61 		cp++;
62 	p = any(cp, " \t");
63 	if (p != NULL)
64 		*p++ = '\0';
65 	net.n_net = inet_network(cp);
66 	net.n_addrtype = AF_INET;
67 	q = net.n_aliases = net_aliases;
68 	if (p != NULL)
69 		cp = p;
70 	while (cp && *cp) {
71 		if (*cp == ' ' || *cp == '\t') {
72 			cp++;
73 			continue;
74 		}
75 		if (q < &net_aliases[MAXALIASES - 1])
76 			*q++ = cp;
77 		cp = any(cp, " \t");
78 		if (cp != NULL)
79 			*cp++ = '\0';
80 	}
81 	*q = NULL;
82 	return (&net);
83 }
84 
85 static char *
86 any(cp, match)
87 	register char *cp;
88 	char *match;
89 {
90 	register char *mp, c;
91 
92 	while (c = *cp) {
93 		for (mp = match; *mp; mp++)
94 			if (*mp == c)
95 				return (cp);
96 		cp++;
97 	}
98 	return ((char *)0);
99 }
100