login/logout.c

   1 /* Copyright (C) 1996-2015 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <errno.h>
  20 #include <string.h>
  21 #include <utmp.h>
  22 #include <sys/time.h>
  23
  24 int
  25 logout (const char *line)
  26 {
  27   struct utmp tmp, utbuf;
  28   struct utmp *ut;
  29   int result = 0;
  30
  31   /* Tell that we want to use the UTMP file.  */
  32   if (utmpname (_PATH_UTMP) == -1)
  33     return 0;
  34
  35   /* Open UTMP file.  */
  36   setutent ();
  37
  38   /* Fill in search information.  */
  39 #if _HAVE_UT_TYPE - 0
  40   tmp.ut_type = USER_PROCESS;
  41 #endif
  42   strncpy (tmp.ut_line, line, sizeof tmp.ut_line);
  43
  44   /* Read the record.  */
  45   if (getutline_r (&tmp, &utbuf, &ut) >= 0)
  46     {
  47       /* Clear information about who & from where.  */
  48       memset (ut->ut_name, '\0', sizeof ut->ut_name);
  49 #if _HAVE_UT_HOST - 0
  50       memset (ut->ut_host, '\0', sizeof ut->ut_host);
  51 #endif
  52 #if _HAVE_UT_TV - 0
  53       struct timeval tv;
  54       __gettimeofday (&tv, NULL);
  55       ut->ut_tv.tv_sec = tv.tv_sec;
  56       ut->ut_tv.tv_usec = tv.tv_usec;
  57 #else
  58       ut->ut_time = time (NULL);
  59 #endif
  60 #if _HAVE_UT_TYPE - 0
  61       ut->ut_type = DEAD_PROCESS;
  62 #endif
  63
  64       if (pututline (ut) != NULL)
  65         result = 1;
  66     }
  67
  68   /* Close UTMP file.  */
  69   endutent ();
  70
  71   return result;
  72 }