xref: /openbsd-src/lib/libutil/logout.c (revision 62a742911104f98b9185b2c6b6007d9b1c36396c)
1 /*	$OpenBSD: logout.c,v 1.4 1998/07/13 02:11:13 millert Exp $	*/
2 /*
3  * Copyright (c) 1988, 1993
4  *	The Regents of the University of California.  All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. All advertising materials mentioning features or use of this software
15  *    must display the following acknowledgement:
16  *	This product includes software developed by the University of
17  *	California, Berkeley and its contributors.
18  * 4. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #if defined(LIBC_SCCS) && !defined(lint)
36 /* from: static char sccsid[] = "@(#)logout.c	8.1 (Berkeley) 6/4/93"; */
37 static char *rcsid = "$Id: logout.c,v 1.4 1998/07/13 02:11:13 millert Exp $";
38 #endif /* LIBC_SCCS and not lint */
39 
40 #include <sys/types.h>
41 #include <sys/time.h>
42 
43 #include <fcntl.h>
44 #include <utmp.h>
45 #include <unistd.h>
46 #include <stdlib.h>
47 #include <string.h>
48 
49 #include "util.h"
50 
51 typedef struct utmp UTMP;
52 
53 int
54 logout(line)
55 	const char *line;
56 {
57 	int fd, rval;
58 	UTMP ut;
59 
60 	if ((fd = open(_PATH_UTMP, O_RDWR, 0)) < 0)
61 		return(0);
62 	rval = 0;
63 	while (read(fd, &ut, sizeof(UTMP)) == sizeof(UTMP)) {
64 		if (!ut.ut_name[0] || strncmp(ut.ut_line, line, UT_LINESIZE))
65 			continue;
66 		bzero(ut.ut_name, UT_NAMESIZE);
67 		bzero(ut.ut_host, UT_HOSTSIZE);
68 		(void)time(&ut.ut_time);
69 		(void)lseek(fd, -(off_t)sizeof(UTMP), SEEK_CUR);
70 		(void)write(fd, &ut, sizeof(UTMP));
71 		rval = 1;
72 	}
73 	(void)close(fd);
74 	return(rval);
75 }
76