1
0
mirror of https://github.com/adtools/clib2.git synced 2025-12-08 14:59:05 +00:00
Files
amiga-clib2/library/stdio_isinfinity.c
Olaf Barthel 91bcdea2a2 Initial import into SourceForge CVS
git-svn-id: file:///Users/olsen/Code/migration-svn-zu-git/logical-line-staging/clib2/trunk@14685 87f5fb63-7c3d-0410-a384-fd976d0f7a62
2004-07-26 16:36:55 +00:00

82 lines
2.6 KiB
C

/*
* $Id: stdio_isinfinity.c,v 1.1.1.1 2004-07-26 16:31:37 obarthel Exp $
*
* :ts=4
*
* Portable ISO 'C' (1994) runtime library for the Amiga computer
* Copyright (c) 2002-2004 by Olaf Barthel <olsen@sourcery.han.de>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Neither the name of Olaf Barthel nor the names of contributors
* may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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.
*/
#ifndef _STDIO_HEADERS_H
#include "stdio_headers.h"
#endif /* _STDIO_HEADERS_H */
/****************************************************************************/
#if defined (FLOATING_POINT_SUPPORT)
int
__is_infinity(long double number)
{
const unsigned long * const raw = (const unsigned long * const)&number;
int result = 0;
ENTER();
/* This assumes that a) 'number' is stored in big endian format
* and b) it is stored in IEEE 754 format.
*/
if(sizeof(number) == 4) /* single precision */
{
/* Exponent = 255 and fraction = 0.0 */
if((raw[0] & 0x7FFFFFFF) == 0x7F800000)
result = 1;
}
else if (sizeof(number) == 8) /* double precision */
{
/* Exponent = 2047 and fraction = 0.0 */
if(((raw[0] & 0x7FFFFFFF) == 0x7FF00000) && (raw[1] == 0))
{
result = 1;
}
}
else if (sizeof(number) == 12) /* extended precision */
{
/* Exponent = 32767 and fraction = 0.0 */
if(((raw[0] & 0x7FFF0000) == 0x7FFF0000) &&
(raw[1] & 0x7FFFFFFF) == 0 && (raw[2] == 0))
{
result = 1;
}
}
RETURN(result);
return(result);
}
#endif /* FLOATING_POINT_SUPPORT */