/* * $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 * 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 */