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Remove arc4random_uniform from arc4random.c
This was previously moved into its own file (matching OpenBSD) which
prematurely committed in commit 73541f2
.
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5f45c2395c
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@ -242,44 +242,6 @@ arc4random_buf(void *_buf, size_t n)
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}
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#endif /* !defined(HAVE_ARC4RANDOM_BUF) && defined(HAVE_ARC4RANDOM) */
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#ifndef HAVE_ARC4RANDOM_UNIFORM
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/*
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* Calculate a uniformly distributed random number less than upper_bound
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* avoiding "modulo bias".
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*
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* Uniformity is achieved by generating new random numbers until the one
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* returned is outside the range [0, 2**32 % upper_bound). This
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* guarantees the selected random number will be inside
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* [2**32 % upper_bound, 2**32) which maps back to [0, upper_bound)
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* after reduction modulo upper_bound.
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*/
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u_int32_t
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arc4random_uniform(u_int32_t upper_bound)
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{
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u_int32_t r, min;
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if (upper_bound < 2)
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return 0;
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/* 2**32 % x == (2**32 - x) % x */
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min = -upper_bound % upper_bound;
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/*
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* This could theoretically loop forever but each retry has
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* p > 0.5 (worst case, usually far better) of selecting a
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* number inside the range we need, so it should rarely need
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* to re-roll.
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*/
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for (;;) {
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r = arc4random();
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if (r >= min)
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break;
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}
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return r % upper_bound;
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}
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#endif /* !HAVE_ARC4RANDOM_UNIFORM */
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#if 0
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/*-------- Test code for i386 --------*/
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#include <stdio.h>
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