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-rw-r--r--src/lib/libc/stdlib/_rand48.c50
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diff --git a/src/lib/libc/stdlib/_rand48.c b/src/lib/libc/stdlib/_rand48.c
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1/*
2 * Copyright (c) 1993 Martin Birgmeier
3 * All rights reserved.
4 *
5 * You may redistribute unmodified or modified versions of this source
6 * code provided that the above copyright notice and this and the
7 * following conditions are retained.
8 *
9 * This software is provided ``as is'', and comes with no warranties
10 * of any kind. I shall in no event be liable for anything that happens
11 * to anyone/anything when using this software.
12 */
13
14#if defined(LIBC_SCCS) && !defined(lint)
15static char rcsid[] = "$OpenBSD: _rand48.c,v 1.2 1996/08/19 08:33:19 tholo Exp $";
16#endif /* LIBC_SCCS and not lint */
17
18#include "rand48.h"
19
20unsigned short __rand48_seed[3] = {
21 RAND48_SEED_0,
22 RAND48_SEED_1,
23 RAND48_SEED_2
24};
25unsigned short __rand48_mult[3] = {
26 RAND48_MULT_0,
27 RAND48_MULT_1,
28 RAND48_MULT_2
29};
30unsigned short __rand48_add = RAND48_ADD;
31
32void
33__dorand48(unsigned short xseed[3])
34{
35 unsigned long accu;
36 unsigned short temp[2];
37
38 accu = (unsigned long) __rand48_mult[0] * (unsigned long) xseed[0] +
39 (unsigned long) __rand48_add;
40 temp[0] = (unsigned short) accu; /* lower 16 bits */
41 accu >>= sizeof(unsigned short) * 8;
42 accu += (unsigned long) __rand48_mult[0] * (unsigned long) xseed[1] +
43 (unsigned long) __rand48_mult[1] * (unsigned long) xseed[0];
44 temp[1] = (unsigned short) accu; /* middle 16 bits */
45 accu >>= sizeof(unsigned short) * 8;
46 accu += __rand48_mult[0] * xseed[2] + __rand48_mult[1] * xseed[1] + __rand48_mult[2] * xseed[0];
47 xseed[0] = temp[0];
48 xseed[1] = temp[1];
49 xseed[2] = (unsigned short) accu;
50}