parse_group.c revision 262435 
1/*
2 * Copyright (c) 1989, 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#ifndef lint
31#if 0
32static const char sccsid[] = "@(#)getgrent.c	8.2 (Berkeley) 3/21/94";
33#endif
34static const char rcsid[] =
35  "$FreeBSD: stable/10/libexec/mknetid/parse_group.c 262435 2014-02-24 08:21:49Z brueffer $";
36#endif /* not lint */
37
38/*
39 * This is a slightly modified chunk of getgrent(3). All the YP support
40 * and unneeded functions have been stripped out.
41 */
42
43#include <sys/types.h>
44#include <grp.h>
45#include <stdio.h>
46#include <stdlib.h>
47#include <string.h>
48
49FILE *_gr_fp;
50static struct group _gr_group;
51static int _gr_stayopen;
52static int grscan(int, int);
53static int start_gr(void);
54
55#define	MAXGRP		200
56static char *members[MAXGRP];
57#define	MAXLINELENGTH	1024
58static char line[MAXLINELENGTH];
59
60struct group *
61_getgrent(void)
62{
63	if (!_gr_fp && !start_gr()) {
64		return NULL;
65	}
66
67
68	if (!grscan(0, 0))
69		return(NULL);
70	return(&_gr_group);
71}
72
73static int
74start_gr(void)
75{
76	return 1;
77}
78
79int
80_setgroupent(int stayopen)
81{
82	if (!start_gr())
83		return(0);
84	_gr_stayopen = stayopen;
85	return(1);
86}
87
88int
89_setgrent(void)
90{
91	return(_setgroupent(0));
92}
93
94void
95_endgrent(void)
96{
97	if (_gr_fp) {
98		(void)fclose(_gr_fp);
99		_gr_fp = NULL;
100	}
101}
102
103static int
104grscan(int search, int gid)
105{
106	char *cp, **m;
107	char *bp;
108	for (;;) {
109		if (!fgets(line, sizeof(line), _gr_fp))
110			return(0);
111		bp = line;
112		/* skip lines that are too big */
113		if (!strchr(line, '\n')) {
114			int ch;
115
116			while ((ch = getc(_gr_fp)) != '\n' && ch != EOF)
117				;
118			continue;
119		}
120		if ((_gr_group.gr_name = strsep(&bp, ":\n")) == NULL)
121			break;
122		if (_gr_group.gr_name[0] == '+')
123			continue;
124		if ((_gr_group.gr_passwd = strsep(&bp, ":\n")) == NULL)
125			break;
126		if (!(cp = strsep(&bp, ":\n")))
127			continue;
128		_gr_group.gr_gid = atoi(cp);
129		if (search && _gr_group.gr_gid != gid)
130			continue;
131		cp = NULL;
132		if (bp == NULL) /* !! Must check for this! */
133			break;
134		for (m = _gr_group.gr_mem = members;; bp++) {
135			if (m == &members[MAXGRP - 1])
136				break;
137			if (*bp == ',') {
138				if (cp) {
139					*bp = '\0';
140					*m++ = cp;
141					cp = NULL;
142				}
143			} else if (*bp == '\0' || *bp == '\n' || *bp == ' ') {
144				if (cp) {
145					*bp = '\0';
146					*m++ = cp;
147			}
148				break;
149			} else if (cp == NULL)
150				cp = bp;
151		}
152		*m = NULL;
153		return(1);
154	}
155	/* NOTREACHED */
156	return (0);
157}
158