33 lines
497 B
C
33 lines
497 B
C
// SPDX-License-Identifier: GPL-2.0+
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/*
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* Simple xorshift PRNG
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* see http://www.jstatsoft.org/v08/i14/paper
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*
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* Copyright (c) 2012 Michael Walle
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* Michael Walle <michael@walle.cc>
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*/
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#include <common.h>
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#include <rand.h>
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static unsigned int y = 1U;
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unsigned int rand_r(unsigned int *seedp)
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{
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*seedp ^= (*seedp << 13);
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*seedp ^= (*seedp >> 17);
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*seedp ^= (*seedp << 5);
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return *seedp;
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}
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unsigned int rand(void)
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{
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return rand_r(&y);
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}
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void srand(unsigned int seed)
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{
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y = seed;
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}
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