xref: /openbsd-src/lib/libc/gen/isinf.c (revision 48950c12d106c85f315112191a0228d7b83b9510)
1 /*	$OpenBSD: isinf.c,v 1.7 2012/12/05 23:19:59 deraadt Exp $	*/
2 /*
3  * Copyright (c) 2008 Martynas Venckus <martynas@openbsd.org>
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 /* LINTLIBRARY */
19 
20 #include <sys/types.h>
21 #include <machine/ieee.h>
22 #include <float.h>
23 
24 int
25 __isinf(double d)
26 {
27 	struct ieee_double *p = (struct ieee_double *)&d;
28 
29 	return (p->dbl_exp == DBL_EXP_INFNAN &&
30 	    p->dbl_frach == 0 && p->dbl_fracl == 0);
31 }
32 
33 int
34 __isinff(float f)
35 {
36 	struct ieee_single *p = (struct ieee_single *)&f;
37 
38 	return (p->sng_exp == SNG_EXP_INFNAN && p->sng_frac == 0);
39 }
40 
41 #if	LDBL_MANT_DIG == 53
42 #ifdef	lint
43 /* PROTOLIB1 */
44 int __isinfl(long double);
45 #else	/* lint */
46 __weak_alias(__isinfl, __isinf);
47 #endif	/* lint */
48 #endif	/* LDBL_MANT_DIG == 53 */
49 
50 /*
51  * 3BSD compatibility aliases.
52  */
53 __weak_alias(isinf, __isinf);
54 __weak_alias(isinff, __isinff);
55