1 /* $OpenBSD: s_lroundl.c,v 1.2 2012/12/05 23:20:04 deraadt 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/limits.h> 30 #include <fenv.h> 31 #include <math.h> 32 33 #ifndef type 34 #if 0 35 __FBSDID("$FreeBSD: src/lib/msun/src/s_lround.c,v 1.2 2005/04/08 00:52:16 das Exp $"); 36 #endif 37 #define type long double 38 #define roundit roundl 39 #define dtype long 40 #define DTYPE_MIN LONG_MIN 41 #define DTYPE_MAX LONG_MAX 42 #define fn lroundl 43 #endif 44 45 /* 46 * If type has more precision than dtype, the endpoints dtype_(min|max) are 47 * of the form xxx.5; they are "out of range" because lround() rounds away 48 * from 0. On the other hand, if type has less precision than dtype, then 49 * all values that are out of range are integral, so we might as well assume 50 * that everything is in range. At compile time, INRANGE(x) should reduce to 51 * two floating-point comparisons in the former case, or TRUE otherwise. 52 */ 53 static const type dtype_min = DTYPE_MIN - 0.5; 54 static const type dtype_max = DTYPE_MAX + 0.5; 55 #define INRANGE(x) (dtype_max - DTYPE_MAX != 0.5 || \ 56 ((x) > dtype_min && (x) < dtype_max)) 57 58 dtype 59 fn(type x) 60 { 61 62 if (INRANGE(x)) { 63 x = roundit(x); 64 return ((dtype)x); 65 } else { 66 feraiseexcept(FE_INVALID); 67 return (DTYPE_MAX); 68 } 69 } 70