debug/readlink_chk.c

   1 /* Copyright (C) 2005-2017 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 #include <unistd.h>
  19 #include <sys/param.h>
  20 #ifdef HAVE_INLINED_SYSCALLS
  21 # include <errno.h>
  22 # include <sysdep.h>
  23 #endif
  24
  25
  26 ssize_t
  27 __readlink_chk (const char *path, void *buf, size_t len, size_t buflen)
  28 {
  29   if (len > buflen)
  30     __chk_fail ();
  31
  32 #ifdef HAVE_INLINED_SYSCALLS
  33   return INLINE_SYSCALL (readlink, 3, path, buf, len);
  34 #else
  35   return __readlink (path, buf, len);
  36 #endif
  37 }