xref: /freebsd/libexec/mknetid/parse_group.c (revision aca5021d5f7dcab1e11692923266373e35322d9a)
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. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 #if 0
36 static const char sccsid[] = "@(#)getgrent.c	8.2 (Berkeley) 3/21/94";
37 #endif
38 static const char rcsid[] =
39   "$FreeBSD$";
40 #endif /* not lint */
41 
42 /*
43  * This is a slightly modified chunk of getgrent(3). All the YP support
44  * and unneeded functions have been stripped out.
45  */
46 
47 #include <sys/types.h>
48 #include <grp.h>
49 #include <stdio.h>
50 #include <stdlib.h>
51 #include <string.h>
52 
53 FILE *_gr_fp;
54 static struct group _gr_group;
55 static int _gr_stayopen;
56 static int grscan(int, int);
57 static int start_gr(void);
58 
59 #define	MAXGRP		200
60 static char *members[MAXGRP];
61 #define	MAXLINELENGTH	1024
62 static char line[MAXLINELENGTH];
63 
64 struct group *
65 _getgrent(void)
66 {
67 	if (!_gr_fp && !start_gr()) {
68 		return NULL;
69 	}
70 
71 
72 	if (!grscan(0, 0))
73 		return(NULL);
74 	return(&_gr_group);
75 }
76 
77 static int
78 start_gr(void)
79 {
80 	return 1;
81 }
82 
83 int
84 _setgroupent(int stayopen)
85 {
86 	if (!start_gr())
87 		return(0);
88 	_gr_stayopen = stayopen;
89 	return(1);
90 }
91 
92 int
93 _setgrent(void)
94 {
95 	return(_setgroupent(0));
96 }
97 
98 void
99 _endgrent(void)
100 {
101 	if (_gr_fp) {
102 		(void)fclose(_gr_fp);
103 		_gr_fp = NULL;
104 	}
105 }
106 
107 static int
108 grscan(int search, int gid)
109 {
110 	char *cp, **m;
111 	char *bp;
112 	for (;;) {
113 		if (!fgets(line, sizeof(line), _gr_fp))
114 			return(0);
115 		bp = line;
116 		/* skip lines that are too big */
117 		if (!strchr(line, '\n')) {
118 			int ch;
119 
120 			while ((ch = getc(_gr_fp)) != '\n' && ch != EOF)
121 				;
122 			continue;
123 		}
124 		if ((_gr_group.gr_name = strsep(&bp, ":\n")) == NULL)
125 			break;
126 		if (_gr_group.gr_name[0] == '+')
127 			continue;
128 		if ((_gr_group.gr_passwd = strsep(&bp, ":\n")) == NULL)
129 			break;
130 		if (!(cp = strsep(&bp, ":\n")))
131 			continue;
132 		_gr_group.gr_gid = atoi(cp);
133 		if (search && _gr_group.gr_gid != gid)
134 			continue;
135 		cp = NULL;
136 		if (bp == NULL) /* !! Must check for this! */
137 			break;
138 		for (m = _gr_group.gr_mem = members;; bp++) {
139 			if (m == &members[MAXGRP - 1])
140 				break;
141 			if (*bp == ',') {
142 				if (cp) {
143 					*bp = '\0';
144 					*m++ = cp;
145 					cp = NULL;
146 				}
147 			} else if (*bp == '\0' || *bp == '\n' || *bp == ' ') {
148 				if (cp) {
149 					*bp = '\0';
150 					*m++ = cp;
151 			}
152 				break;
153 			} else if (cp == NULL)
154 				cp = bp;
155 		}
156 		*m = NULL;
157 		return(1);
158 	}
159 	/* NOTREACHED */
160 	return (0);
161 }
162