1 /* $NetBSD: erand48.c,v 1.9 2006/03/22 20:52:16 drochner Exp $ */ 2 3 /* 4 * Copyright (c) 1993 Martin Birgmeier 5 * All rights reserved. 6 * 7 * You may redistribute unmodified or modified versions of this source 8 * code provided that the above copyright notice and this and the 9 * following conditions are retained. 10 * 11 * This software is provided ``as is'', and comes with no warranties 12 * of any kind. I shall in no event be liable for anything that happens 13 * to anyone/anything when using this software. 14 */ 15 16 #include <sys/cdefs.h> 17 #if defined(LIBC_SCCS) && !defined(lint) 18 __RCSID("$NetBSD: erand48.c,v 1.9 2006/03/22 20:52:16 drochner Exp $"); 19 #endif /* LIBC_SCCS and not lint */ 20 21 #include "namespace.h" 22 23 #include <assert.h> 24 #include <math.h> 25 26 #include "rand48.h" 27 28 #ifdef __weak_alias __weak_alias(erand48,_erand48)29__weak_alias(erand48,_erand48) 30 #endif 31 32 double 33 erand48(unsigned short xseed[3]) 34 { 35 36 _DIAGASSERT(xseed != NULL); 37 38 __dorand48(xseed); 39 return ldexp((double) xseed[0], -48) + 40 ldexp((double) xseed[1], -32) + 41 ldexp((double) xseed[2], -16); 42 } 43