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/*
* Implementation of non-cryptographic pseudo-random number
* generator algorithm known as xoshiro.
*
* This file is part of mpv.
*
* mpv 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.
*
* mpv 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 mpv. If not, see <http://www.gnu.org/licenses/>.
*/
#pragma once
#include <stdint.h>
/*
* Internal state for the PRNG, should be initialized via mp_rand_seed().
*/
typedef struct mp_rand_state {
uint64_t v[4];
} mp_rand_state;
/*
* Initialize the pseudo-random number generator's state with
* the given 64-bit seed. If the seed is 0, it is randomized.
*/
mp_rand_state mp_rand_seed(uint64_t seed);
/*
* Return the next 64-bit pseudo-random integer, and update the state
* accordingly.
*/
uint64_t mp_rand_next(mp_rand_state *s);
/*
* Return a double value in the range of [0.0, 1.0) with uniform
* distribution, and update the state accordingly.
*/
double mp_rand_next_double(mp_rand_state *s);
/*
* Return a 32 bit integer in the range [min, max) with uniform distribution.
* Caller should ensure `min < max`.
*/
uint32_t mp_rand_in_range32(mp_rand_state *s, uint32_t min, uint32_t max);
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