NetBSD/lib/libc/gen/isinfl_dbl_ieee754.c

78 lines
2.7 KiB
C

/* $NetBSD: isinfl_dbl_ieee754.c,v 1.2 2003/10/24 10:30:36 kleink Exp $ */
/*
* Copyright (c) 1992, 1993
* The Regents of the University of California. All rights reserved.
*
* This software was developed by the Computer Systems Engineering group
* at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
* contributed to Berkeley.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* from: Header: isinf.c,v 1.1 91/07/08 19:03:34 torek Exp
*/
#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char sccsid[] = "@(#)isinf.c 8.1 (Berkeley) 6/4/93";
#else
__RCSID("$NetBSD: isinfl_dbl_ieee754.c,v 1.2 2003/10/24 10:30:36 kleink Exp $");
#endif
#endif /* LIBC_SCCS and not lint */
#include "namespace.h"
#include <sys/types.h>
#include <machine/ieee.h>
#include <float.h>
#include <math.h>
#if 0 /* XXX Currently limited to internal use. */
#ifdef __weak_alias
__weak_alias(isinfl,_isinfl)
#endif
#endif
#if LDBL_MANT_DIG != DBL_MANT_DIG
#error double / long double mismatch
#endif
/*
* isinfl() for platforms where long double == double.
*/
int
isinfl(long double ld)
{
union {
long double ld;
struct ieee_double dbl;
} u;
u.ld = ld;
return (u.dbl.dbl_exp == DBL_EXP_INFNAN &&
(u.dbl.dbl_frach == 0 && u.dbl.dbl_fracl == 0));
}