/* Copyright (C) 1992-2018 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 <string.h>

#include <stdlib.h>

#include <time.h>

#include <unistd.h>

char *

strfry (char *string)

{

  static int init;

  static struct random_data rdata;

  if (!init)

    {

      static char state[32];

      rdata.state = NULL;

      __initstate_r (time ((time_t *) NULL) ^ getpid (),

		     state, sizeof (state), &rdata);

      init = 1;

    }

  size_t len = strlen (string);

  if (len > 0)

    for (size_t i = 0; i < len - 1; ++i)

      {

	int32_t j;

	__random_r (&rdata, &j);

	j = j % (len - i) + i;

	char c = string[i];

	string[i] = string[j];

	string[j] = c;

      }

  return string;

}