nptl/sysdeps/unix/sysv/linux/timer_gettime.c

   1 /* Copyright (C) 2003 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@redhat.com>, 2003.
   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 License as
   7    published by the Free Software Foundation; either version 2.1 of the
   8    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; see the file COPYING.LIB.  If not,
  17    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18    Boston, MA 02111-1307, USA.  */
  19
  20 #include <errno.h>
  21 #include <stdlib.h>
  22 #include <time.h>
  23 #include <sysdep.h>
  24 #include <kernel-features.h>
  25 #include "kernel-posix-timers.h"
  26
  27
  28 #ifdef __NR_timer_gettime
  29 # ifndef __ASSUME_POSIX_TIMERS
  30 static int compat_timer_gettime (timer_t timerid, struct itimerspec *value);
  31 #  define timer_gettime static compat_timer_gettime
  32 #  include <nptl/sysdeps/pthread/timer_gettime.c>
  33 #  undef timer_gettime
  34 # endif
  35
  36 # ifdef timer_gettime_alias
  37 #  define timer_gettime timer_gettime_alias
  38 # endif
  39
  40
  41 int
  42 timer_gettime (timerid, value)
  43      timer_t timerid;
  44      struct itimerspec *value;
  45 {
  46 # undef timer_gettime
  47 # ifndef __ASSUME_POSIX_TIMERS
  48   if (__no_posix_timers >= 0)
  49 # endif
  50     {
  51       struct timer *kt = (struct timer *) timerid;
  52
  53       /* Delete the kernel timer object.  */
  54       int res = INLINE_SYSCALL (timer_gettime, 2, kt->ktimerid, value);
  55
  56 # ifndef __ASSUME_POSIX_TIMERS
  57       if (res != -1 || errno != ENOSYS)
  58         {
  59           /* We know the syscall support is available.  */
  60           __no_posix_timers = 1;
  61 # endif
  62           return res;
  63 # ifndef __ASSUME_POSIX_TIMERS
  64         }
  65 # endif
  66
  67 # ifndef __ASSUME_POSIX_TIMERS
  68       __no_posix_timers = -1;
  69 # endif
  70     }
  71
  72 # ifndef __ASSUME_POSIX_TIMERS
  73   return compat_timer_gettime (timerid, value);
  74 # endif
  75 }
  76 #else
  77 # ifdef timer_gettime_alias
  78 #  define timer_gettime timer_gettime_alias
  79 # endif
  80 /* The new system calls are not available.  Use the userlevel
  81    implementation.  */
  82 # include <nptl/sysdeps/pthread/timer_gettime.c>
  83 #endif