xref: /openbsd-src/lib/libc/net/getprotoent.c (revision 0038de2c7a95ab6cde30035b4c13f3d21c8a1310)
1 /*	$OpenBSD: getprotoent.c,v 1.8 2005/08/06 20:30:03 espie Exp $ */
2 /*
3  * Copyright (c) 1983, 1993
4  *	The Regents of the University of California.  All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. Neither the name of the University nor the names of its contributors
15  *    may be used to endorse or promote products derived from this software
16  *    without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <sys/types.h>
32 #include <sys/socket.h>
33 
34 #include <errno.h>
35 #include <netdb.h>
36 #include <stdio.h>
37 #include <stdlib.h>
38 #include <string.h>
39 
40 void
41 setprotoent_r(int f, struct protoent_data *pd)
42 {
43 	if (pd->fp == NULL)
44 		pd->fp = fopen(_PATH_PROTOCOLS, "r" );
45 	else
46 		rewind(pd->fp);
47 	pd->stayopen |= f;
48 }
49 
50 void
51 endprotoent_r(struct protoent_data *pd)
52 {
53 	if (pd->fp) {
54 		fclose(pd->fp);
55 		pd->fp = NULL;
56 	}
57 	free(pd->aliases);
58 	pd->aliases = NULL;
59 	pd->maxaliases = 0;
60 	free(pd->line);
61 	pd->line = NULL;
62 	pd->stayopen = 0;
63 }
64 
65 int
66 getprotoent_r(struct protoent *pe, struct protoent_data *pd)
67 {
68 	char *p, *cp, **q, *endp;
69 	size_t len;
70 	long l;
71 	int serrno;
72 
73 	if (pd->fp == NULL && (pd->fp = fopen(_PATH_PROTOCOLS, "r" )) == NULL)
74 		return (-1);
75 again:
76 	if ((p = fgetln(pd->fp, &len)) == NULL)
77 		return (-1);
78 	if (len == 0 || *p == '#' || *p == '\n')
79 		goto again;
80 	if (p[len-1] == '\n')
81 		len--;
82 	if ((cp = memchr(p, '#', len)) != NULL)
83 		len = cp - p;
84 	cp = realloc(pd->line, len + 1);
85 	if (cp == NULL)
86 		return (-1);
87 	pd->line = pe->p_name = memcpy(cp, p, len);
88 	cp[len] = '\0';
89 	cp = strpbrk(cp, " \t");
90 	if (cp == NULL)
91 		goto again;
92 	*cp++ = '\0';
93 	while (*cp == ' ' || *cp == '\t')
94 		cp++;
95 	p = strpbrk(cp, " \t");
96 	if (p != NULL)
97 		*p++ = '\0';
98 	l = strtol(cp, &endp, 10);
99 	if (endp == cp || *endp != '\0' || l < 0 || l >= INT_MAX)
100 		goto again;
101 	pe->p_proto = l;
102 	if (pd->aliases == NULL) {
103 		pd->maxaliases = 5;
104 		pd->aliases = malloc(pd->maxaliases * sizeof(char *));
105 		if (pd->aliases == NULL) {
106 			serrno = errno;
107 			endprotoent_r(pd);
108 			errno = serrno;
109 			return (-1);
110 		}
111 	}
112 	q = pe->p_aliases = pd->aliases;
113 	if (p != NULL) {
114 		cp = p;
115 		while (cp && *cp) {
116 			if (*cp == ' ' || *cp == '\t') {
117 				cp++;
118 				continue;
119 			}
120 			if (q == &pe->p_aliases[pd->maxaliases - 1]) {
121 				p = realloc(pe->p_aliases,
122 				    2 * pd->maxaliases * sizeof(char *));
123 				if (p == NULL) {
124 					serrno = errno;
125 					endprotoent_r(pd);
126 					errno = serrno;
127 					return (-1);
128 				}
129 				pd->maxaliases *= 2;
130 				q = (char **)p + (q - pe->p_aliases);
131 				pe->p_aliases = pd->aliases = (char **)p;
132 			}
133 			*q++ = cp;
134 			cp = strpbrk(cp, " \t");
135 			if (cp != NULL)
136 				*cp++ = '\0';
137 		}
138 	}
139 	*q = NULL;
140 	return (0);
141 }
142 
143 struct protoent_data _protoent_data;	/* shared with getproto{,name}.c */
144 
145 void
146 setprotoent(int f)
147 {
148 	setprotoent_r(f, &_protoent_data);
149 }
150 
151 void
152 endprotoent(void)
153 {
154 	endprotoent_r(&_protoent_data);
155 }
156 
157 struct protoent *
158 getprotoent(void)
159 {
160 	static struct protoent proto;
161 
162 	if (getprotoent_r(&proto, &_protoent_data) != 0)
163 		return (NULL);
164 	return (&proto);
165 }
166