sysdeps/unix/sysv/linux/clock_gettime.c

   1 /* clock_gettime -- Get current time from a POSIX clockid_t.  Linux version.
   2    Copyright (C) 2003-2014 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_GETTIME_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 #ifndef SYSCALL_GETTIME
  35 # define SYSCALL_GETTIME(id, tp) \
  36   INLINE_VSYSCALL (clock_gettime, 2, id, tp)
  37 #endif
  38 #ifndef INTERNAL_GETTIME
  39 # define INTERNAL_GETTIME(id, tp) \
  40   INTERNAL_VSYSCALL (clock_gettime, err, 2, id, tp)
  41 #endif
  42
  43 /* The REALTIME and MONOTONIC clock are definitely supported in the
  44    kernel.  */
  45 #define SYSDEP_GETTIME \
  46   SYSDEP_GETTIME_CPUTIME;                                                     \
  47   case CLOCK_REALTIME:                                                        \
  48   case CLOCK_MONOTONIC:                                                       \
  49     retval = SYSCALL_GETTIME (clock_id, tp);                                  \
  50     break
  51
  52 /* We handled the REALTIME clock here.  */
  53 #define HANDLED_REALTIME        1
  54 #define HANDLED_CPUTIME 1
  55
  56 #define SYSDEP_GETTIME_CPU(clock_id, tp) \
  57   retval = SYSCALL_GETTIME (clock_id, tp); \
  58   break
  59 #define SYSDEP_GETTIME_CPUTIME  /* Default catches them too.  */
  60
  61 #include <sysdeps/unix/clock_gettime.c>