getgrent.c revision 1.1.1.1.2.1 
1/*	$NetBSD: getgrent.c,v 1.1.1.1.2.1 1995/10/11 23:51:58 gwr Exp $	*/
2
3/*
4 * Copyright (c) 1989, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 * Portions Copyright (c) 1994, Jason Downs. All Rights Reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 *    must display the following acknowledgement:
18 *	This product includes software developed by the University of
19 *	California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 *    may be used to endorse or promote products derived from this software
22 *    without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37/*
38 * Copied from:  lib/libc/gen/getgrent.c
39 * and then gutted, leaving only /etc/group support.
40 */
41
42#include <sys/types.h>
43#include <stdio.h>
44#include <stdlib.h>
45#include <string.h>
46#include <grp.h>
47
48static FILE *_gr_fp;
49static struct group _gr_group;
50static int _gr_stayopen;
51static int grscan(), start_gr();
52
53#define	MAXGRP		200
54static char *members[MAXGRP];
55#define	MAXLINELENGTH	1024
56static char line[MAXLINELENGTH];
57
58struct group *
59getgrent()
60{
61	if (!_gr_fp && !start_gr() || !grscan(0, 0, NULL))
62		return(NULL);
63	return(&_gr_group);
64}
65
66struct group *
67getgrnam(name)
68	const char *name;
69{
70	int rval;
71
72	if (!start_gr())
73		return(NULL);
74	rval = grscan(1, 0, name);
75	if (!_gr_stayopen)
76		endgrent();
77	return(rval ? &_gr_group : NULL);
78}
79
80struct group *
81#ifdef __STDC__
82getgrgid(gid_t gid)
83#else
84getgrgid(gid)
85	gid_t gid;
86#endif
87{
88	int rval;
89
90	if (!start_gr())
91		return(NULL);
92	rval = grscan(1, gid, NULL);
93	if (!_gr_stayopen)
94		endgrent();
95	return(rval ? &_gr_group : NULL);
96}
97
98static int
99start_gr()
100{
101	if (_gr_fp) {
102		rewind(_gr_fp);
103		return(1);
104	}
105	return((_gr_fp = fopen(_PATH_GROUP, "r")) ? 1 : 0);
106}
107
108void
109setgrent()
110{
111	(void) setgroupent(0);
112}
113
114int
115setgroupent(stayopen)
116	int stayopen;
117{
118	if (!start_gr())
119		return(0);
120	_gr_stayopen = stayopen;
121	return(1);
122}
123
124void
125endgrent()
126{
127	if (_gr_fp) {
128		(void)fclose(_gr_fp);
129		_gr_fp = NULL;
130	}
131}
132
133static int
134grscan(search, gid, name)
135	register int search, gid;
136	register char *name;
137{
138	register char *cp, **m;
139	char *bp;
140
141	for (;;) {
142		if (!fgets(line, sizeof(line), _gr_fp))
143			return(0);
144		bp = line;
145		/* skip lines that are too big */
146		if (!strchr(line, '\n')) {
147			int ch;
148
149			while ((ch = getc(_gr_fp)) != '\n' && ch != EOF)
150				;
151			continue;
152		}
153		_gr_group.gr_name = strsep(&bp, ":\n");
154		if (search && name && strcmp(_gr_group.gr_name, name))
155			continue;
156		_gr_group.gr_passwd = strsep(&bp, ":\n");
157		if (!(cp = strsep(&bp, ":\n")))
158			continue;
159		_gr_group.gr_gid = atoi(cp);
160		if (search && name == NULL && _gr_group.gr_gid != gid)
161			continue;
162		cp = NULL;
163		if (bp == NULL)
164			continue;
165		for (m = _gr_group.gr_mem = members;; bp++) {
166			if (m == &members[MAXGRP - 1])
167				break;
168			if (*bp == ',') {
169				if (cp) {
170					*bp = '\0';
171					*m++ = cp;
172					cp = NULL;
173				}
174			} else if (*bp == '\0' || *bp == '\n' || *bp == ' ') {
175				if (cp) {
176					*bp = '\0';
177					*m++ = cp;
178				}
179				break;
180			} else if (cp == NULL)
181				cp = bp;
182		}
183		*m = NULL;
184		return(1);
185	}
186	/* NOTREACHED */
187}
188