xref: /csrg-svn/libexec/ftpd/logwtmp.c (revision 36773)
1 /*
2  * Copyright (c) 1988 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms are permitted
6  * provided that the above copyright notice and this paragraph are
7  * duplicated in all such forms and that any documentation,
8  * advertising materials, and other materials related to such
9  * distribution and use acknowledge that the software was developed
10  * by the University of California, Berkeley.  The name of the
11  * University may not be used to endorse or promote products derived
12  * from this software without specific prior written permission.
13  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
14  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
15  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
16  *
17  */
18 
19 #ifndef lint
20 static char sccsid[] = "@(#)logwtmp.c	5.4 (Berkeley) 02/14/89";
21 #endif /* not lint */
22 
23 #include <sys/types.h>
24 #include <sys/file.h>
25 #include <sys/time.h>
26 #include <sys/stat.h>
27 #include <utmp.h>
28 
29 #define	WTMPFILE	"/usr/adm/wtmp"
30 
31 static int fd = -1;
32 
33 /*
34  * Modified version of logwtmp that holds wtmp file open
35  * after first call, for use with ftp (which may chroot
36  * after login, but before logout).
37  */
38 logwtmp(line, name, host)
39 	char *line, *name, *host;
40 {
41 	struct utmp ut;
42 	struct stat buf;
43 	time_t time();
44 	char *strncpy();
45 
46 	if (fd < 0 && (fd = open(WTMPFILE, O_WRONLY|O_APPEND, 0)) < 0)
47 		return;
48 	if (fstat(fd, &buf) == 0) {
49 		(void)strncpy(ut.ut_line, line, sizeof(ut.ut_line));
50 		(void)strncpy(ut.ut_name, name, sizeof(ut.ut_name));
51 		(void)strncpy(ut.ut_host, host, sizeof(ut.ut_host));
52 		(void)time(&ut.ut_time);
53 		if (write(fd, (char *)&ut, sizeof(struct utmp)) !=
54 		    sizeof(struct utmp))
55 			(void)ftruncate(fd, buf.st_size);
56 	}
57 }
58