misc/logwtmp.c

   1 /*
   2  * Copyright (c) 1988, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   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  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #if defined(LIBC_SCCS) && !defined(lint)
  35 static char sccsid[] = "@(#)logwtmp.c   8.1 (Berkeley) 6/4/93";
  36 #endif /* LIBC_SCCS and not lint */
  37
  38 #include <sys/types.h>
  39 #include <sys/file.h>
  40 #include <sys/stat.h>
  41 #include <time.h>
  42 #include <string.h>
  43
  44 #include <unistd.h>
  45 #include <utmp.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 }