sysdeps/unix/sysv/linux/clock_getres.c

   1 /* clock_getres -- Get the resolution of a POSIX clockid_t.  Linux version.
   2    Copyright (C) 2003-2013 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   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 <sysdep.h>
  20 #include <errno.h>
  21 #include <time.h>
  22 #include "kernel-posix-cpu-timers.h"
  23 #include <kernel-features.h>
  24
  25 #ifndef HAVE_CLOCK_GETRES_VSYSCALL
  26 # undef INTERNAL_VSYSCALL
  27 # define INTERNAL_VSYSCALL INTERNAL_SYSCALL
  28 # undef INLINE_VSYSCALL
  29 # define INLINE_VSYSCALL INLINE_SYSCALL
  30 #else
  31 # include <bits/libc-vdso.h>
  32 #endif
  33
  34 #define SYSCALL_GETRES \
  35   retval = INLINE_VSYSCALL (clock_getres, 2, clock_id, res); \
  36   break
  37
  38 /* The REALTIME and MONOTONIC clock are definitely supported in the
  39    kernel.  */
  40 #define SYSDEP_GETRES                                                         \
  41   SYSDEP_GETRES_CPUTIME                                                       \
  42   case CLOCK_REALTIME:                                                        \
  43   case CLOCK_MONOTONIC:                                                       \
  44   case CLOCK_MONOTONIC_RAW:                                                   \
  45   case CLOCK_REALTIME_COARSE:                                                 \
  46   case CLOCK_MONOTONIC_COARSE:                                                \
  47     SYSCALL_GETRES
  48
  49 /* We handled the REALTIME clock here.  */
  50 #define HANDLED_REALTIME        1
  51 #define HANDLED_CPUTIME         1
  52
  53 #define SYSDEP_GETRES_CPU SYSCALL_GETRES
  54 #define SYSDEP_GETRES_CPUTIME   /* Default catches them too.  */
  55
  56 #include <sysdeps/posix/clock_getres.c>