133965Sjdp/*	$OpenBSD: drand48.c,v 1.7 2015/09/14 13:30:17 guenther Exp $ */
289857Sobrien/*
360484Sobrien * Copyright (c) 1993 Martin Birgmeier
433965Sjdp * All rights reserved.
533965Sjdp *
633965Sjdp * You may redistribute unmodified or modified versions of this source
733965Sjdp * code provided that the above copyright notice and this and the
833965Sjdp * following conditions are retained.
933965Sjdp *
1033965Sjdp * This software is provided ``as is'', and comes with no warranties
1133965Sjdp * of any kind. I shall in no event be liable for anything that happens
1233965Sjdp * to anyone/anything when using this software.
1333965Sjdp */
1433965Sjdp
1533965Sjdp#include <math.h>
1633965Sjdp#include "rand48.h"
1733965Sjdp
1860484Sobriendouble
1960484Sobriendrand48(void)
2060484Sobrien{
2133965Sjdp	if (__rand48_deterministic == 0) {
2289857Sobrien		unsigned short rseed[3];
2389857Sobrien
2489857Sobrien		arc4random_buf(rseed, sizeof rseed);
2589857Sobrien		return ldexp((double) rseed[0], -48) +
2633965Sjdp		       ldexp((double) rseed[1], -32) +
2733965Sjdp		       ldexp((double) rseed[2], -16);
2833965Sjdp	}
2933965Sjdp	return erand48(__rand48_seed);
3033965Sjdp}
3189857Sobrien