xref: /netbsd-src/lib/libc/gen/getgrouplist.c (revision 5e4c038a45edbc7d63b7c2daa76e29f88b64a4e3)
1 /*	$NetBSD: getgrouplist.c,v 1.15 2000/01/22 22:19:10 mycroft Exp $	*/
2 
3 /*
4  * Copyright (c) 1991, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/cdefs.h>
37 #if defined(LIBC_SCCS) && !defined(lint)
38 #if 0
39 static char sccsid[] = "@(#)getgrouplist.c	8.2 (Berkeley) 12/8/94";
40 #else
41 __RCSID("$NetBSD: getgrouplist.c,v 1.15 2000/01/22 22:19:10 mycroft Exp $");
42 #endif
43 #endif /* LIBC_SCCS and not lint */
44 
45 /*
46  * get credential
47  */
48 #include "namespace.h"
49 #include <sys/param.h>
50 
51 #include <assert.h>
52 #include <grp.h>
53 #include <string.h>
54 #include <unistd.h>
55 
56 #ifdef __weak_alias
57 __weak_alias(getgrouplist,_getgrouplist)
58 #endif
59 
60 int
61 getgrouplist(uname, agroup, groups, grpcnt)
62 	const char *uname;
63 	gid_t agroup;
64 	gid_t *groups;
65 	int *grpcnt;
66 {
67 	struct group *grp;
68 	int i, ngroups;
69 	int ret, maxgroups;
70 
71 	_DIAGASSERT(uname != NULL);
72 	_DIAGASSERT(groups != NULL);
73 	_DIAGASSERT(grpcnt != NULL);
74 
75 	ret = 0;
76 	ngroups = 0;
77 	maxgroups = *grpcnt;
78 
79 	/*
80 	 * install primary group
81 	 */
82 	if (ngroups < maxgroups)
83 		groups[ngroups] = agroup;
84 	else
85 		ret = -1;
86 	ngroups++;
87 
88 	/*
89 	 * Scan the group file to find additional groups.
90 	 */
91 	setgrent();
92  nextgroup:
93 	while ((grp = getgrent()) != NULL) {
94 		if (grp->gr_gid == agroup)
95 			continue;
96 		for (i = 0; grp->gr_mem[i]; i++) {
97 			if (!strcmp(grp->gr_mem[i], uname)) {
98 				for (i = 0; i < MIN(ngroups, maxgroups); i++) {
99 					if (grp->gr_gid == groups[i])
100 						goto nextgroup;
101 				}
102 				if (ngroups < maxgroups)
103 					groups[ngroups] = grp->gr_gid;
104 				else
105 					ret = -1;
106 				ngroups++;
107 				break;
108 			}
109 		}
110 	}
111 	endgrent();
112 	*grpcnt = ngroups;
113 	return (ret);
114 }
115