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
  17    not, see <http://www.gnu.org/licenses/>.  */
  18
  19 #include <errno.h>
  20 #include <stdlib.h>
  21 #include <time.h>
  22 #include <sysdep.h>
  23 #include <kernel-features.h>
  24 #include "kernel-posix-timers.h"
  25
  26
  27 #ifdef __NR_timer_gettime
  28 # ifndef __ASSUME_POSIX_TIMERS
  29 static int compat_timer_gettime (timer_t timerid, struct itimerspec *value);
  30 #  define timer_gettime static compat_timer_gettime
  31 #  include <nptl/sysdeps/pthread/timer_gettime.c>
  32 #  undef timer_gettime
  33 # endif
  34
  35 # ifdef timer_gettime_alias
  36 #  define timer_gettime timer_gettime_alias
  37 # endif
  38
  39
  40 int
  41 timer_gettime (timerid, value)
  42      timer_t timerid;
  43      struct itimerspec *value;
  44 {
  45 # undef timer_gettime
  46 # ifndef __ASSUME_POSIX_TIMERS
  47   if (__no_posix_timers >= 0)
  48 # endif
  49     {
  50       struct timer *kt = (struct timer *) timerid;
  51
  52       /* Delete the kernel timer object.  */
  53       int res = INLINE_SYSCALL (timer_gettime, 2, kt->ktimerid, value);
  54
  55 # ifndef __ASSUME_POSIX_TIMERS
  56       if (res != -1 || errno != ENOSYS)
  57         {
  58           /* We know the syscall support is available.  */
  59           __no_posix_timers = 1;
  60 # endif
  61           return res;
  62 # ifndef __ASSUME_POSIX_TIMERS
  63         }
  64 # endif
  65
  66 # ifndef __ASSUME_POSIX_TIMERS
  67       __no_posix_timers = -1;
  68 # endif
  69     }
  70
  71 # ifndef __ASSUME_POSIX_TIMERS
  72   return compat_timer_gettime (timerid, value);
  73 # endif
  74 }
  75 #else
  76 # ifdef timer_gettime_alias
  77 #  define timer_gettime timer_gettime_alias
  78 # endif
  79 /* The new system calls are not available.  Use the userlevel
  80    implementation.  */
  81 # include <nptl/sysdeps/pthread/timer_gettime.c>
  82 #endif