1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 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 #define type double 35 #define roundit round 36 #define dtype long 37 #define DTYPE_MIN LONG_MIN 38 #define DTYPE_MAX LONG_MAX 39 #define fn lround 40 #endif 41 42 /* 43 * If type has more precision than dtype, the endpoints dtype_(min|max) are 44 * of the form xxx.5; they are "out of range" because lround() rounds away 45 * from 0. On the other hand, if type has less precision than dtype, then 46 * all values that are out of range are integral, so we might as well assume 47 * that everything is in range. At compile time, INRANGE(x) should reduce to 48 * two floating-point comparisons in the former case, or TRUE otherwise. 49 */ 50 static const type type_min = (type)DTYPE_MIN; 51 static const type type_max = (type)DTYPE_MAX; 52 static const type dtype_min = (type)DTYPE_MIN - 0.5; 53 static const type dtype_max = (type)DTYPE_MAX + 0.5; 54 #define INRANGE(x) (dtype_max - type_max != 0.5 || \ 55 ((x) > dtype_min && (x) < dtype_max)) 56 57 dtype 58 fn(type x) 59 { 60 61 if (INRANGE(x)) { 62 x = roundit(x); 63 return ((dtype)x); 64 } else { 65 feraiseexcept(FE_INVALID); 66 return (DTYPE_MAX); 67 } 68 } 69