1*05a0b428SJohn Marino /* $OpenBSD: s_lroundl.c,v 1.2 2012/12/05 23:20:04 deraadt Exp $ */
2*05a0b428SJohn Marino
3*05a0b428SJohn Marino /*-
4*05a0b428SJohn Marino * Copyright (c) 2005 David Schultz <das@FreeBSD.ORG>
5*05a0b428SJohn Marino * All rights reserved.
6*05a0b428SJohn Marino *
7*05a0b428SJohn Marino * Redistribution and use in source and binary forms, with or without
8*05a0b428SJohn Marino * modification, are permitted provided that the following conditions
9*05a0b428SJohn Marino * are met:
10*05a0b428SJohn Marino * 1. Redistributions of source code must retain the above copyright
11*05a0b428SJohn Marino * notice, this list of conditions and the following disclaimer.
12*05a0b428SJohn Marino * 2. Redistributions in binary form must reproduce the above copyright
13*05a0b428SJohn Marino * notice, this list of conditions and the following disclaimer in the
14*05a0b428SJohn Marino * documentation and/or other materials provided with the distribution.
15*05a0b428SJohn Marino *
16*05a0b428SJohn Marino * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17*05a0b428SJohn Marino * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18*05a0b428SJohn Marino * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19*05a0b428SJohn Marino * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20*05a0b428SJohn Marino * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21*05a0b428SJohn Marino * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22*05a0b428SJohn Marino * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23*05a0b428SJohn Marino * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24*05a0b428SJohn Marino * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25*05a0b428SJohn Marino * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26*05a0b428SJohn Marino * SUCH DAMAGE.
27*05a0b428SJohn Marino */
28*05a0b428SJohn Marino
29*05a0b428SJohn Marino #include <sys/limits.h>
30*05a0b428SJohn Marino #include <fenv.h>
31*05a0b428SJohn Marino #include <math.h>
32*05a0b428SJohn Marino
33*05a0b428SJohn Marino #ifndef type
34*05a0b428SJohn Marino #if 0
35*05a0b428SJohn Marino __FBSDID("$FreeBSD: src/lib/msun/src/s_lround.c,v 1.2 2005/04/08 00:52:16 das Exp $");
36*05a0b428SJohn Marino #endif
37*05a0b428SJohn Marino #define type long double
38*05a0b428SJohn Marino #define roundit roundl
39*05a0b428SJohn Marino #define dtype long
40*05a0b428SJohn Marino #define DTYPE_MIN LONG_MIN
41*05a0b428SJohn Marino #define DTYPE_MAX LONG_MAX
42*05a0b428SJohn Marino #define fn lroundl
43*05a0b428SJohn Marino #endif
44*05a0b428SJohn Marino
45*05a0b428SJohn Marino /*
46*05a0b428SJohn Marino * If type has more precision than dtype, the endpoints dtype_(min|max) are
47*05a0b428SJohn Marino * of the form xxx.5; they are "out of range" because lround() rounds away
48*05a0b428SJohn Marino * from 0. On the other hand, if type has less precision than dtype, then
49*05a0b428SJohn Marino * all values that are out of range are integral, so we might as well assume
50*05a0b428SJohn Marino * that everything is in range. At compile time, INRANGE(x) should reduce to
51*05a0b428SJohn Marino * two floating-point comparisons in the former case, or TRUE otherwise.
52*05a0b428SJohn Marino */
53*05a0b428SJohn Marino static const type dtype_min = DTYPE_MIN - 0.5;
54*05a0b428SJohn Marino static const type dtype_max = DTYPE_MAX + 0.5;
55*05a0b428SJohn Marino #define INRANGE(x) (dtype_max - DTYPE_MAX != 0.5 || \
56*05a0b428SJohn Marino ((x) > dtype_min && (x) < dtype_max))
57*05a0b428SJohn Marino
58*05a0b428SJohn Marino dtype
fn(type x)59*05a0b428SJohn Marino fn(type x)
60*05a0b428SJohn Marino {
61*05a0b428SJohn Marino
62*05a0b428SJohn Marino if (INRANGE(x)) {
63*05a0b428SJohn Marino x = roundit(x);
64*05a0b428SJohn Marino return ((dtype)x);
65*05a0b428SJohn Marino } else {
66*05a0b428SJohn Marino feraiseexcept(FE_INVALID);
67*05a0b428SJohn Marino return (DTYPE_MAX);
68*05a0b428SJohn Marino }
69*05a0b428SJohn Marino }
70