xref: /original-bsd/lib/libc/gen/getgrent.c (revision 3588a932)
1 /*
2  * Copyright (c) 1989 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * %sccs.include.redist.c%
6  */
7 
8 #if defined(LIBC_SCCS) && !defined(lint)
9 static char sccsid[] = "@(#)getgrent.c	5.8 (Berkeley) 02/23/91";
10 #endif /* LIBC_SCCS and not lint */
11 
12 #include <sys/types.h>
13 #include <stdio.h>
14 #include <stdlib.h>
15 #include <grp.h>
16 
17 static FILE *_gr_fp;
18 static struct group _gr_group;
19 static int _gr_stayopen;
20 static const char *_gr_file = _PATH_GROUP;
21 static start_gr();
22 static grscan();
23 
24 #define	MAXGRP		200
25 static char *members[MAXGRP];
26 #define	MAXLINELENGTH	1024
27 static char line[MAXLINELENGTH];
28 
29 struct group *
30 getgrent()
31 {
32 	if (!_gr_fp && !start_gr() || !grscan(0, 0, (char *)NULL))
33 		return((struct group *)NULL);
34 	return(&_gr_group);
35 }
36 
37 struct group *
38 getgrnam(name)
39 	const char *name;
40 {
41 	int rval;
42 
43 	if (!start_gr())
44 		return((struct group *)NULL);
45 	rval = grscan(1, 0, name);
46 	if (!_gr_stayopen)
47 		endgrent();
48 	return(rval ? &_gr_group : (struct group *)NULL);
49 }
50 
51 struct group *
52 #ifdef __STDC__
53 getgrgid(gid_t gid)
54 #else
55 getgrgid(gid)
56 	gid_t gid;
57 #endif
58 {
59 	int rval;
60 
61 	if (!start_gr())
62 		return((struct group *)NULL);
63 	rval = grscan(1, gid, (char *)NULL);
64 	if (!_gr_stayopen)
65 		endgrent();
66 	return(rval ? &_gr_group : (struct group *)NULL);
67 }
68 
69 static
70 start_gr()
71 {
72 	if (_gr_fp) {
73 		rewind(_gr_fp);
74 		return(1);
75 	}
76 	return((_gr_fp = fopen(_gr_file, "r")) ? 1 : 0);
77 }
78 
79 int
80 setgrent()
81 {
82 	return(setgroupent(0));
83 }
84 
85 int
86 setgroupent(stayopen)
87 	int stayopen;
88 {
89 	if (!start_gr())
90 		return(0);
91 	_gr_stayopen = stayopen;
92 	return(1);
93 }
94 
95 void
96 endgrent()
97 {
98 	if (_gr_fp) {
99 		(void)fclose(_gr_fp);
100 		_gr_fp = (FILE *)NULL;
101 	}
102 }
103 
104 void
105 setgrfile(file)
106 	const char *file;
107 {
108 	_gr_file = file;
109 }
110 
111 static
112 grscan(search, gid, name)
113 	register int search, gid;
114 	register char *name;
115 {
116 	register char *cp, **m;
117 	char *bp;
118 	char *fgets(), *strsep(), *index();
119 
120 	for (;;) {
121 		if (!fgets(line, sizeof(line), _gr_fp))
122 			return(0);
123 		bp = line;
124 		/* skip lines that are too big */
125 		if (!index(line, '\n')) {
126 			int ch;
127 
128 			while ((ch = getc(_gr_fp)) != '\n' && ch != EOF)
129 				;
130 			continue;
131 		}
132 		_gr_group.gr_name = strsep(&bp, ":\n");
133 		if (search && name && strcmp(_gr_group.gr_name, name))
134 			continue;
135 		_gr_group.gr_passwd = strsep(&bp, ":\n");
136 		if (!(cp = strsep(&bp, ":\n")))
137 			continue;
138 		_gr_group.gr_gid = atoi(cp);
139 		if (search && name == NULL && _gr_group.gr_gid != gid)
140 			continue;
141 		for (m = _gr_group.gr_mem = members;; ++m) {
142 			if (m == &members[MAXGRP - 1]) {
143 				*m = NULL;
144 				break;
145 			}
146 			if ((*m = strsep(&bp, ", \n")) == NULL)
147 				break;
148 		}
149 		return(1);
150 	}
151 	/* NOTREACHED */
152 }
153