busybox/shell/random.h
Denys Vlasenko 3ea2e82dc7 ash: factor out $RANDOM support
function                                             old     new   delta
next_random                                            -      46     +46
ash_main                                            1361    1356      -5
change_random                                        132      97     -35
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(add/remove: 1/0 grow/shrink: 0/2 up/down: 46/-40)              Total: 6 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2009-10-09 20:59:04 +02:00

20 lines
492 B
C

/* vi: set sw=4 ts=4: */
/*
* $RANDOM support.
*
* Copyright (C) 2008 Denys Vlasenko
*
* Licensed under GPLv2, see file LICENSE in this tarball for details.
*/
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 INIT_RANDOM_T(rnd, nonzero, v) \
((rnd)->galois_LFSR = (nonzero), (rnd)->LCG = (v))
uint32_t next_random(random_t *rnd) FAST_FUNC;