sysdeps/unix/sysv/linux/powerpc/gettimeofday.c

   1 /* Copyright (C) 2005-2019 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, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 #if defined SHARED && !defined __powerpc64__
  19 # define __gettimeofday __redirect___gettimeofday
  20 #else
  21 # define __redirect___gettimeofday __gettimeofday
  22 #endif
  23
  24 #include <sys/time.h>
  25
  26 #ifdef SHARED
  27
  28 # include <dl-vdso.h>
  29 # include <libc-vdso.h>
  30 # include <dl-machine.h>
  31
  32 # ifndef __powerpc64__
  33 #  undef __gettimeofday
  34
  35 int
  36 __gettimeofday_vsyscall (struct timeval *tv, struct timezone *tz)
  37 {
  38   return INLINE_VSYSCALL (gettimeofday, 2, tv, tz);
  39 }
  40
  41 /* __GI___gettimeofday is defined as hidden and for ppc32 it enables the
  42    compiler make a local call (symbol@local) for internal GLIBC usage. It
  43    means the PLT won't be used and the ifunc resolver will be called directly.
  44    For ppc64 a call to a function in another translation unit might use a
  45    different toc pointer thus disallowing direct branchess and making internal
  46    ifuncs calls safe.  */
  47 #  undef libc_hidden_def
  48 #  define libc_hidden_def(name)                                 \
  49   __hidden_ver1 (__gettimeofday_vsyscall, __GI___gettimeofday,  \
  50                __gettimeofday_vsyscall);
  51
  52 # endif /* !__powerpc64__  */
  53
  54 static int
  55 __gettimeofday_syscall (struct timeval *tv, struct timezone *tz)
  56 {
  57   return INLINE_SYSCALL (gettimeofday, 2, tv, tz);
  58 }
  59
  60 # define INIT_ARCH()                                            \
  61   PREPARE_VERSION_KNOWN (linux2615, LINUX_2_6_15);              \
  62   void *vdso_gettimeofday = _dl_vdso_vsym ("__kernel_gettimeofday", &linux2615);
  63
  64 /* If the vDSO is not available we fall back syscall.  */
  65 libc_ifunc_hidden (__redirect___gettimeofday, __gettimeofday,
  66                    vdso_gettimeofday
  67                    ? VDSO_IFUNC_RET (vdso_gettimeofday)
  68                    : (void *) __gettimeofday_syscall);
  69 libc_hidden_def (__gettimeofday)
  70
  71 #else
  72
  73 # include <sysdep.h>
  74 # include <errno.h>
  75
  76 int
  77 __gettimeofday (struct timeval *tv, struct timezone *tz)
  78 {
  79   return INLINE_SYSCALL (gettimeofday, 2, tv, tz);
  80 }
  81 libc_hidden_def (__gettimeofday)
  82
  83 #endif
  84 weak_alias (__gettimeofday, gettimeofday)
  85 libc_hidden_weak (gettimeofday)