27 lines
716 B
C
27 lines
716 B
C
// Copyright 2013-2023 Nicholas J. Kain <njkain at gmail dot com>
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// SPDX-License-Identifier: MIT
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#include <stdint.h>
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#include "nk/hwrng.h"
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#include "nk/random.h"
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void nk_random_init(struct nk_random_state *s)
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{
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nk_hwrng_bytes(s->seed, sizeof(uint64_t) * 3);
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s->seed[3] = 1;
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for (size_t i = 0; i < 12; ++i) nk_random_u64(s);
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}
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static inline uint64_t rotl64(const uint64_t x, int k) {
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return (x << k) | (x >> (64 - k));
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}
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uint64_t nk_random_u64(struct nk_random_state *s)
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{
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const uint64_t t = s->seed[0] + s->seed[1] + s->seed[3]++;
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s->seed[0] = s->seed[1] ^ (s->seed[1] >> 11);
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s->seed[1] = s->seed[2] + (s->seed[2] << 3);
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s->seed[2] = rotl64(s->seed[2], 24) + t;
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return t;
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}
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