glibc/login/programs/utmpdump.c

100 lines
2.4 KiB
C

/* utmpdump - dump utmp-like files.
Copyright (C) 1997-2017 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Mark Kettenis <kettenis@phys.uva.nl>, 1997.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <unistd.h>
#include <utmp.h>
static void
print_entry (struct utmp *up)
{
/* Mixed 32-/64-bit systems may have timeval structs of different sixe
but need struct utmp to be the same size. So in 64-bit up->ut_tv may
not be a timeval but a struct of __int32_t's. This would cause a compile
time warning and a formating error when 32-bit int is passed where
a 64-bit long is expected. So copy up->up_tv to a temporary timeval.
This is 32-/64-bit agnostic and expands the timeval fields to the
expected size as needed. */
struct timeval temp_tv;
temp_tv.tv_sec = up->ut_tv.tv_sec;
temp_tv.tv_usec = up->ut_tv.tv_usec;
(printf) (
/* The format string. */
#if _HAVE_UT_TYPE
"[%d] "
#endif
#if _HAVE_UT_PID
"[%05d] "
#endif
#if _HAVE_UT_ID
"[%-4.4s] "
#endif
"[%-8.8s] [%-12.12s]"
#if _HAVE_UT_HOST
" [%-16.16s]"
#endif
" [%-15.15s]"
#if _HAVE_UT_TV
" [%ld]"
#endif
"\n"
/* The arguments. */
#if _HAVE_UT_TYPE
, up->ut_type
#endif
#if _HAVE_UT_PID
, up->ut_pid
#endif
#if _HAVE_UT_ID
, up->ut_id
#endif
, up->ut_user, up->ut_line
#if _HAVE_UT_HOST
, up->ut_host
#endif
#if _HAVE_UT_TV
, 4 + ctime (&temp_tv.tv_sec)
, (long int) temp_tv.tv_usec
#else
, 4 + ctime (&up->ut_time)
#endif
);
}
int
main (int argc, char *argv[])
{
struct utmp *up;
if (argc > 1)
utmpname (argv[1]);
setutent ();
while ((up = getutent ()))
print_entry (up);
endutent ();
return EXIT_SUCCESS;
}