xref: /freebsd/libexec/mknetid/parse_group.c (revision dd41de95a84d979615a2ef11df6850622bf6184e)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1989, 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. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #ifndef lint
33 #if 0
34 static const char sccsid[] = "@(#)getgrent.c	8.2 (Berkeley) 3/21/94";
35 #endif
36 static const char rcsid[] =
37   "$FreeBSD$";
38 #endif /* not lint */
39 
40 /*
41  * This is a slightly modified chunk of getgrent(3). All the YP support
42  * and unneeded functions have been stripped out.
43  */
44 
45 #include <sys/types.h>
46 #include <grp.h>
47 #include <stdio.h>
48 #include <stdlib.h>
49 #include <string.h>
50 
51 FILE *_gr_fp;
52 static struct group _gr_group;
53 static int _gr_stayopen;
54 static int grscan(int, int);
55 static int start_gr(void);
56 
57 #define	MAXGRP		200
58 static char *members[MAXGRP];
59 #define	MAXLINELENGTH	1024
60 static char line[MAXLINELENGTH];
61 
62 struct group *
63 _getgrent(void)
64 {
65 	if (!_gr_fp && !start_gr()) {
66 		return NULL;
67 	}
68 
69 
70 	if (!grscan(0, 0))
71 		return(NULL);
72 	return(&_gr_group);
73 }
74 
75 static int
76 start_gr(void)
77 {
78 	return 1;
79 }
80 
81 int
82 _setgroupent(int stayopen)
83 {
84 	if (!start_gr())
85 		return(0);
86 	_gr_stayopen = stayopen;
87 	return(1);
88 }
89 
90 int
91 _setgrent(void)
92 {
93 	return(_setgroupent(0));
94 }
95 
96 void
97 _endgrent(void)
98 {
99 	if (_gr_fp) {
100 		(void)fclose(_gr_fp);
101 		_gr_fp = NULL;
102 	}
103 }
104 
105 static int
106 grscan(int search, int gid)
107 {
108 	char *cp, **m;
109 	char *bp;
110 	for (;;) {
111 		if (!fgets(line, sizeof(line), _gr_fp))
112 			return(0);
113 		bp = line;
114 		/* skip lines that are too big */
115 		if (!strchr(line, '\n')) {
116 			int ch;
117 
118 			while ((ch = getc(_gr_fp)) != '\n' && ch != EOF)
119 				;
120 			continue;
121 		}
122 		if ((_gr_group.gr_name = strsep(&bp, ":\n")) == NULL)
123 			break;
124 		if (_gr_group.gr_name[0] == '+')
125 			continue;
126 		if ((_gr_group.gr_passwd = strsep(&bp, ":\n")) == NULL)
127 			break;
128 		if (!(cp = strsep(&bp, ":\n")))
129 			continue;
130 		_gr_group.gr_gid = atoi(cp);
131 		if (search && _gr_group.gr_gid != gid)
132 			continue;
133 		cp = NULL;
134 		if (bp == NULL) /* !! Must check for this! */
135 			break;
136 		for (m = _gr_group.gr_mem = members;; bp++) {
137 			if (m == &members[MAXGRP - 1])
138 				break;
139 			if (*bp == ',') {
140 				if (cp) {
141 					*bp = '\0';
142 					*m++ = cp;
143 					cp = NULL;
144 				}
145 			} else if (*bp == '\0' || *bp == '\n' || *bp == ' ') {
146 				if (cp) {
147 					*bp = '\0';
148 					*m++ = cp;
149 			}
150 				break;
151 			} else if (cp == NULL)
152 				cp = bp;
153 		}
154 		*m = NULL;
155 		return(1);
156 	}
157 	/* NOTREACHED */
158 	return (0);
159 }
160