kernel - SWAP CACHE part 22/many - Fix counter overflow introduced in part 21
[dragonfly.git] / lib / libutil / logout.c
blob59ce97557fe9e5d4f2814f67358624e397169d93
1 /*-
2 * Copyright (c) 1988, 1993
3 * The Regents of the University of California. All rights reserved.
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 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
29 * @(#)logout.c 8.1 (Berkeley) 6/4/93
30 * $FreeBSD: src/lib/libutil/logout.c,v 1.6.2.2 2000/09/20 09:54:16 jkh Exp $
31 * $DragonFly: src/lib/libutil/logout.c,v 1.5 2007/12/30 13:44:33 matthias Exp $
34 #include <sys/types.h>
35 #include <sys/time.h>
37 #include <fcntl.h>
38 #include <utmp.h>
39 #include <unistd.h>
40 #include <stdlib.h>
41 #include <string.h>
43 #include "libutil.h"
45 typedef struct utmp UTMP;
47 int
48 logout(const char *line)
50 int fd;
51 UTMP ut;
52 int rval;
54 if ((fd = open(_PATH_UTMP, O_RDWR, 0)) < 0)
55 return(0);
56 rval = 0;
57 while (read(fd, &ut, sizeof(UTMP)) == sizeof(UTMP)) {
58 if (!ut.ut_name[0] || strncmp(ut.ut_line, line, UT_LINESIZE))
59 continue;
60 bzero(ut.ut_name, UT_NAMESIZE);
61 bzero(ut.ut_host, UT_HOSTSIZE);
62 (void)time(&ut.ut_time);
63 (void)lseek(fd, -(off_t)sizeof(UTMP), L_INCR);
64 (void)write(fd, &ut, sizeof(UTMP));
65 rval = 1;
67 (void)close(fd);
68 return(rval);