/* Operating system specific code for generic dynamic loader functions.

   Copyright (C) 2009-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or

   modify it under the terms of the GNU Lesser General Public

   License as published by the Free Software Foundation; either

   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public

   License along with the GNU C Library; if not, see

   <http://www.gnu.org/licenses/>.  */

#include <endian.h>

#include <stdint.h>

static inline uintptr_t __attribute__ ((always_inline))

_dl_setup_stack_chk_guard (void *dl_random)

{

  union

  {

    uintptr_t num;

    unsigned char bytes[sizeof (uintptr_t)];

  } ret = { 0 };

  if (dl_random == NULL)

    {

      ret.bytes[sizeof (ret) - 1] = 255;

      ret.bytes[sizeof (ret) - 2] = '\n';

    }

  else

    {

      memcpy (ret.bytes, dl_random, sizeof (ret));

#if BYTE_ORDER == LITTLE_ENDIAN

      ret.num &= ~(uintptr_t) 0xff;

#elif BYTE_ORDER == BIG_ENDIAN

      ret.num &= ~((uintptr_t) 0xff << (8 * (sizeof (ret) - 1)));

#else

# error "BYTE_ORDER unknown"

#endif

    }

  return ret.num;

}

static inline uintptr_t __attribute__ ((always_inline))

_dl_setup_pointer_guard (void *dl_random, uintptr_t stack_chk_guard)

{

  uintptr_t ret;

  if (dl_random == NULL)

    ret = stack_chk_guard;

  else

    memcpy (&ret, (char *) dl_random + sizeof (ret), sizeof (ret));

  return ret;

}