xref: /openbsd-src/lib/libc/net/getnetent.c (revision 62a742911104f98b9185b2c6b6007d9b1c36396c)
1 /*
2  * Copyright (c) 1983, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #if defined(LIBC_SCCS) && !defined(lint)
35 static char rcsid[] = "$OpenBSD: getnetent.c,v 1.8 1998/03/16 05:06:57 millert Exp $";
36 #endif /* LIBC_SCCS and not lint */
37 
38 #include <sys/types.h>
39 #include <sys/socket.h>
40 #include <netinet/in.h>
41 #include <arpa/inet.h>
42 #include <netdb.h>
43 #include <stdio.h>
44 #include <string.h>
45 
46 #define	MAXALIASES	35
47 
48 static FILE *netf;
49 static char line[BUFSIZ+1];
50 static struct netent net;
51 static char *net_aliases[MAXALIASES];
52 int _net_stayopen;
53 
54 void
55 setnetent(f)
56 	int f;
57 {
58 	if (netf == NULL)
59 		netf = fopen(_PATH_NETWORKS, "r" );
60 	else
61 		rewind(netf);
62 	_net_stayopen |= f;
63 }
64 
65 void
66 endnetent()
67 {
68 	if (netf) {
69 		fclose(netf);
70 		netf = NULL;
71 	}
72 	_net_stayopen = 0;
73 }
74 
75 struct netent *
76 getnetent()
77 {
78 	char *p, *cp, **q;
79 	size_t len;
80 
81 	if (netf == NULL && (netf = fopen(_PATH_NETWORKS, "r" )) == NULL)
82 		return (NULL);
83 again:
84 	if ((p = fgetln(netf, &len)) == NULL)
85 		return (NULL);
86 	if (p[len-1] == '\n')
87 		len--;
88 	if (len >= sizeof(line) || len == 0)
89 		goto again;
90 	p = memcpy(line, p, len);
91 	line[len] = '\0';
92 	if (*p == '#')
93 		goto again;
94 	if ((cp = strchr(p, '#')) != NULL)
95 		*cp = '\0';
96 	net.n_name = p;
97 	if (strlen(net.n_name) >= MAXHOSTNAMELEN-1)
98 		net.n_name[MAXHOSTNAMELEN-1] = '\0';
99 	cp = strpbrk(p, " \t");
100 	if (cp == NULL)
101 		goto again;
102 	*cp++ = '\0';
103 	while (*cp == ' ' || *cp == '\t')
104 		cp++;
105 	p = strpbrk(cp, " \t");
106 	if (p != NULL)
107 		*p++ = '\0';
108 	net.n_net = inet_network(cp);
109 	net.n_addrtype = AF_INET;
110 	q = net.n_aliases = net_aliases;
111 	if (p != NULL)
112 		cp = p;
113 	while (cp && *cp) {
114 		if (*cp == ' ' || *cp == '\t') {
115 			cp++;
116 			continue;
117 		}
118 		if (q < &net_aliases[MAXALIASES - 1]) {
119 			*q++ = cp;
120 			if (strlen(cp) >= MAXHOSTNAMELEN-1)
121 				cp[MAXHOSTNAMELEN-1] = '\0';
122 		}
123 		cp = strpbrk(cp, " \t");
124 		if (cp != NULL)
125 			*cp++ = '\0';
126 	}
127 	*q = NULL;
128 	return (&net);
129 }
130