xref: /openbsd/lib/libc/stdlib/seed48.c (revision 09467b48)
1 /*	$OpenBSD: seed48.c,v 1.6 2015/09/13 15:20:40 guenther Exp $ */
2 /*
3  * Copyright (c) 1993 Martin Birgmeier
4  * All rights reserved.
5  *
6  * You may redistribute unmodified or modified versions of this source
7  * code provided that the above copyright notice and this and the
8  * following conditions are retained.
9  *
10  * This software is provided ``as is'', and comes with no warranties
11  * of any kind. I shall in no event be liable for anything that happens
12  * to anyone/anything when using this software.
13  */
14 
15 #include "rand48.h"
16 
17 unsigned short *
18 seed48(unsigned short xseed[3])
19 {
20 	unsigned short *res;
21 
22 	res = seed48_deterministic(xseed);
23 	__rand48_deterministic = 0;
24 	return res;
25 }
26 
27 unsigned short *
28 seed48_deterministic(unsigned short xseed[3])
29 {
30 	static unsigned short sseed[3];
31 
32 	__rand48_deterministic = 1;
33 	sseed[0] = __rand48_seed[0];
34 	sseed[1] = __rand48_seed[1];
35 	sseed[2] = __rand48_seed[2];
36 	__rand48_seed[0] = xseed[0];
37 	__rand48_seed[1] = xseed[1];
38 	__rand48_seed[2] = xseed[2];
39 	__rand48_mult[0] = RAND48_MULT_0;
40 	__rand48_mult[1] = RAND48_MULT_1;
41 	__rand48_mult[2] = RAND48_MULT_2;
42 	__rand48_add = RAND48_ADD;
43 	return sseed;
44 }
45 DEF_WEAK(seed48_deterministic);
46