utmp.c revision 1.4 1 /* $NetBSD: utmp.c,v 1.4 2002/08/01 23:46:37 nathanw Exp $ */
2
3 /*-
4 * Copyright (c) 2002 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Christos Zoulas.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by the NetBSD
21 * Foundation, Inc. and its contributors.
22 * 4. Neither the name of The NetBSD Foundation nor the names of its
23 * contributors may be used to endorse or promote products derived
24 * from this software without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36 * POSSIBILITY OF SUCH DAMAGE.
37 */
38 #include <sys/cdefs.h>
39
40 #if defined(LIBC_SCCS) && !defined(lint)
41 __RCSID("$NetBSD: utmp.c,v 1.4 2002/08/01 23:46:37 nathanw Exp $");
42 #endif /* LIBC_SCCS and not lint */
43
44 #include <sys/types.h>
45 #include <sys/param.h>
46 #include <stdio.h>
47 #include <string.h>
48 #include <time.h>
49 #include <utmp.h>
50
51 static struct utmp utmp;
52 static FILE *ut;
53 static char utfile[MAXPATHLEN] = _PATH_UTMP;
54
55 void
56 setutent(void)
57 {
58 if (ut == NULL)
59 return;
60 (void)fseeko(ut, (off_t)0, SEEK_SET);
61 }
62
63 struct utmp *
64 getutent(void)
65 {
66 if (ut == NULL) {
67 if ((ut = fopen(utfile, "r")) == NULL)
68 return NULL;
69 }
70 if (fread(&utmp, sizeof(utmp), 1, ut) == 1)
71 return &utmp;
72 return NULL;
73 }
74
75 void
76 endutent(void)
77 {
78 if (ut != NULL) {
79 (void)fclose(ut);
80 ut = NULL;
81 }
82 }
83
84 int
85 utmpname(const char *fname)
86 {
87 size_t len = strlen(fname);
88
89 if (len >= sizeof(utfile))
90 return 0;
91
92 /* must not end in x! */
93 if (fname[len - 1] == 'x')
94 return 0;
95
96 (void)strcpy(utfile, fname);
97 endutent();
98 return 1;
99 }
100