1 /* $OpenBSD: s_lroundl.c,v 1.1 2011/07/06 00:02:42 martynas Exp $ */ 2 3 /*- 4 * Copyright (c) 2005 David Schultz <das@FreeBSD.ORG> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 #include <sys/limits.h> 31 #include <fenv.h> 32 #include <math.h> 33 34 #ifndef type 35 #if 0 36 __FBSDID("$FreeBSD: src/lib/msun/src/s_lround.c,v 1.2 2005/04/08 00:52:16 das Exp $"); 37 #endif 38 #define type long double 39 #define roundit roundl 40 #define dtype long 41 #define DTYPE_MIN LONG_MIN 42 #define DTYPE_MAX LONG_MAX 43 #define fn lroundl 44 #endif 45 46 /* 47 * If type has more precision than dtype, the endpoints dtype_(min|max) are 48 * of the form xxx.5; they are "out of range" because lround() rounds away 49 * from 0. On the other hand, if type has less precision than dtype, then 50 * all values that are out of range are integral, so we might as well assume 51 * that everything is in range. At compile time, INRANGE(x) should reduce to 52 * two floating-point comparisons in the former case, or TRUE otherwise. 53 */ 54 static const type dtype_min = DTYPE_MIN - 0.5; 55 static const type dtype_max = DTYPE_MAX + 0.5; 56 #define INRANGE(x) (dtype_max - DTYPE_MAX != 0.5 || \ 57 ((x) > dtype_min && (x) < dtype_max)) 58 59 dtype 60 fn(type x) 61 { 62 63 if (INRANGE(x)) { 64 x = roundit(x); 65 return ((dtype)x); 66 } else { 67 feraiseexcept(FE_INVALID); 68 return (DTYPE_MAX); 69 } 70 } 71