xref: /openbsd-src/lib/libutil/logwtmp.c (revision 33b4f39fbeffad07bc3206f173cff9f3c9901cd1)
1 /*	$OpenBSD: logwtmp.c,v 1.6 2003/06/02 20:18:42 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. Neither the name of the University nor the names of its contributors
15  *    may be used to endorse or promote products derived from this software
16  *    without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #if defined(LIBC_SCCS) && !defined(lint)
32 /* from: static char sccsid[] = "@(#)logwtmp.c	8.1 (Berkeley) 6/4/93"; */
33 static const char rcsid[] = "$Id: logwtmp.c,v 1.6 2003/06/02 20:18:42 millert Exp $";
34 #endif /* LIBC_SCCS and not lint */
35 
36 #include <sys/types.h>
37 #include <sys/time.h>
38 #include <sys/stat.h>
39 
40 #include <fcntl.h>
41 #include <string.h>
42 #include <unistd.h>
43 #include <utmp.h>
44 
45 #include "util.h"
46 
47 void
48 logwtmp(line, name, host)
49 	const char *line, *name, *host;
50 {
51 	struct utmp ut;
52 	struct stat buf;
53 	int fd;
54 
55 	if ((fd = open(_PATH_WTMP, O_WRONLY|O_APPEND, 0)) < 0)
56 		return;
57 	if (fstat(fd, &buf) == 0) {
58 		(void) strncpy(ut.ut_line, line, sizeof(ut.ut_line));
59 		(void) strncpy(ut.ut_name, name, sizeof(ut.ut_name));
60 		(void) strncpy(ut.ut_host, host, sizeof(ut.ut_host));
61 		(void) time(&ut.ut_time);
62 		if (write(fd, (char *)&ut, sizeof(struct utmp)) !=
63 		    sizeof(struct utmp))
64 			(void) ftruncate(fd, buf.st_size);
65 	}
66 	(void) close(fd);
67 }
68