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/*
* Simple xorshift PRNG
* see http://www.jstatsoft.org/v08/i14/paper
*
* Copyright (c) 2012 Michael Walle
* Michael Walle <michael@walle.cc>
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <common.h>
static unsigned int y = 1U;
unsigned int rand_r(unsigned int *seedp)
{
*seedp ^= (*seedp << 13);
*seedp ^= (*seedp >> 17);
*seedp ^= (*seedp << 5);
return *seedp;
}
unsigned int rand(void)
{
return rand_r(&y);
}
void srand(unsigned int seed)
{
y = seed;
}