busybox/shell/random.h

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/* vi: set sw=4 ts=4: */
/*
* $RANDOM support.
*
* Copyright (C) 2009 Denys Vlasenko
*
* Licensed under GPLv2, see file LICENSE in this tarball for details.
*/
#ifndef SHELL_RANDOM_H
#define SHELL_RANDOM_H 1
PUSH_AND_SET_FUNCTION_VISIBILITY_TO_HIDDEN
typedef struct random_t {
/* Random number generators */
int32_t galois_LFSR; /* Galois LFSR (fast but weak). signed! */
uint32_t LCG; /* LCG (fast but weak) */
} random_t;
#define UNINITED_RANDOM_T(rnd) \
((rnd)->galois_LFSR == 0)
#define INIT_RANDOM_T(rnd, nonzero, v) \
((rnd)->galois_LFSR = (nonzero), (rnd)->LCG = (v))
#define CLEAR_RANDOM_T(rnd) \
((rnd)->galois_LFSR = 0)
uint32_t next_random(random_t *rnd) FAST_FUNC;
POP_SAVED_FUNCTION_VISIBILITY
#endif