xref: /freebsd/libexec/mknetid/parse_group.c (revision 2008043f386721d58158e37e0d7e50df8095942d)
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 #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 
49 FILE *_gr_fp;
50 static struct group _gr_group;
51 static int _gr_stayopen;
52 static int grscan(int, int);
53 static int start_gr(void);
54 
55 #define	MAXGRP		200
56 static char *members[MAXGRP];
57 #define	MAXLINELENGTH	1024
58 static char line[MAXLINELENGTH];
59 
60 struct 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 
73 static int
74 start_gr(void)
75 {
76 	return 1;
77 }
78 
79 int
80 _setgroupent(int stayopen)
81 {
82 	if (!start_gr())
83 		return(0);
84 	_gr_stayopen = stayopen;
85 	return(1);
86 }
87 
88 int
89 _setgrent(void)
90 {
91 	return(_setgroupent(0));
92 }
93 
94 void
95 _endgrent(void)
96 {
97 	if (_gr_fp) {
98 		(void)fclose(_gr_fp);
99 		_gr_fp = NULL;
100 	}
101 }
102 
103 static int
104 grscan(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