incubator-nuttx/libs/libc/string/lib_explicit_bzero.c

/****************************************************************************
 * libs/libc/string/lib_explicit_bzero.c
 *
 *   Copyright (C) 2015,2017 Haltian Ltd. All rights reserved.
 *   Author: Juha Niskanen <juha.niskanen@haltian.com>
 *           Jussi Kivilinna <jussi.kivilinna@haltian.com>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name NuttX nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <string.h>

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/* memset that must not be optimized away by compiler (not even with LTO). */

void explicit_bzero(FAR void *s, size_t n)
{
  static FAR void *(*FAR const volatile memset_v)(FAR void *, int, size_t) =
      &memset;

  memset_v(s, 0, n);
}