sysdeps/unix/sysv/linux/x86_64/init-first.c

   1 /* Copyright (C) 2007 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, write to the Free
  16    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  17    02111-1307 USA.  */
  18
  19 #ifdef SHARED
  20 # include <dl-vdso.h>
  21 # include <bits/libc-vdso.h>
  22
  23 long int (*__vdso_gettimeofday) (struct timeval *, void *) attribute_hidden;
  24
  25 long int (*__vdso_clock_gettime) (clockid_t, struct timespec *)
  26   __attribute__ ((nocommon));
  27 strong_alias (__vdso_clock_gettime, __GI___vdso_clock_gettime attribute_hidden)
  28
  29
  30 static inline void
  31 _libc_vdso_platform_setup (void)
  32 {
  33   PREPARE_VERSION (linux26, "LINUX_2.6", 61765110);
  34
  35   void *p = _dl_vdso_vsym ("gettimeofday", &linux26);
  36   /* If the vDSO is not available we fall back on the old vsyscall.  */
  37 #define VSYSCALL_ADDR_vgettimeofday     0xffffffffff600000ul
  38   if (p == NULL)
  39     p = (void *) VSYSCALL_ADDR_vgettimeofday;
  40   PTR_MANGLE (p);
  41   __vdso_gettimeofday = p;
  42
  43   p = _dl_vdso_vsym ("clock_gettime", &linux26);
  44   PTR_MANGLE (p);
  45   __GI___vdso_clock_gettime = p;
  46 }
  47
  48 # define VDSO_SETUP _libc_vdso_platform_setup
  49 #endif
  50
  51 #include "../init-first.c"