1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* 23 * Copyright 1986 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #pragma ident "%Z%%M% %I% %E% SMI" 28 29 /* 30 * Recognize an infinity or a NaN when one is presented. 31 * This is for keeping various IO routines out of trouble 32 */ 33 34 35 int 36 isinf( d0, d1 ) 37 unsigned d0,d1; 38 /* a lie -- actually its a ``double'' */ 39 { 40 if (d1 != 0 ) return 0; /* nope -- low-order must be all zeros */ 41 if (d0 != 0x7ff00000 && d0 != 0xfff00000) return 0; /* nope */ 42 return 1; 43 } 44 45 int 46 isnan( d0,d1 ) 47 unsigned d0,d1; 48 /* a lie -- actually its a ``double'' */ 49 { 50 #define EXPONENT 0x7ff00000 51 #define SIGN 0x80000000 52 if ((d0 & EXPONENT) != EXPONENT ) return 0; /* exponent wrong */ 53 if ((d0 & ~(EXPONENT|SIGN)) == 0 && d1 == 0 ) return 0; /* must have bits */ 54 return 1; 55 } 56