xref: /openbsd-src/lib/libc/net/getservent.c (revision db3296cf5c1dd9058ceecc3a29fe4aaa0bd26000)
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. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #if defined(LIBC_SCCS) && !defined(lint)
31 static char rcsid[] = "$OpenBSD: getservent.c,v 1.6 2003/06/02 20:18:35 millert Exp $";
32 #endif /* LIBC_SCCS and not lint */
33 
34 #include <sys/types.h>
35 #include <sys/socket.h>
36 #include <netdb.h>
37 #include <stdio.h>
38 #include <string.h>
39 #include <stdlib.h>
40 
41 #define	MAXALIASES	35
42 
43 static FILE *servf = NULL;
44 static char line[BUFSIZ+1];
45 static struct servent serv;
46 static char *serv_aliases[MAXALIASES];
47 int _serv_stayopen;
48 
49 void
50 setservent(f)
51 	int f;
52 {
53 	if (servf == NULL)
54 		servf = fopen(_PATH_SERVICES, "r" );
55 	else
56 		rewind(servf);
57 	_serv_stayopen |= f;
58 }
59 
60 void
61 endservent()
62 {
63 	if (servf) {
64 		fclose(servf);
65 		servf = NULL;
66 	}
67 	_serv_stayopen = 0;
68 }
69 
70 struct servent *
71 getservent()
72 {
73 	char *p, *cp, **q, *endp;
74 	long l;
75 	size_t len;
76 
77 	if (servf == NULL && (servf = fopen(_PATH_SERVICES, "r" )) == NULL)
78 		return (NULL);
79 again:
80 	if ((p = fgetln(servf, &len)) == NULL)
81 		return (NULL);
82 	if (p[len-1] == '\n')
83 		len--;
84 	if (len >= sizeof(line) || len == 0)
85 		goto again;
86 	p = memcpy(line, p, len);
87 	line[len] = '\0';
88 	if (*p == '#')
89 		goto again;
90 	if ((cp = strchr(p, '#')) != NULL)
91 		*cp = '\0';
92 	serv.s_name = p;
93 	p = strpbrk(p, " \t");
94 	if (p == NULL)
95 		goto again;
96 	*p++ = '\0';
97 	while (*p == ' ' || *p == '\t')
98 		p++;
99 	cp = strpbrk(p, ",/");
100 	if (cp == NULL)
101 		goto again;
102 	*cp++ = '\0';
103 	l = strtol(p, &endp, 10);
104 	if (endp == p || *endp != '\0' || l < 0 || l > USHRT_MAX)
105 		goto again;
106 	serv.s_port = htons((in_port_t)l);
107 	serv.s_proto = cp;
108 	q = serv.s_aliases = serv_aliases;
109 	cp = strpbrk(cp, " \t");
110 	if (cp != NULL)
111 		*cp++ = '\0';
112 	while (cp && *cp) {
113 		if (*cp == ' ' || *cp == '\t') {
114 			cp++;
115 			continue;
116 		}
117 		if (q < &serv_aliases[MAXALIASES - 1])
118 			*q++ = cp;
119 		cp = strpbrk(cp, " \t");
120 		if (cp != NULL)
121 			*cp++ = '\0';
122 	}
123 	*q = NULL;
124 	return (&serv);
125 }
126