/* Copyright (C) 1991, 1992, 1995 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ #include /* * @implemented */ int _isnan(double __x) { union { double* __x; double_s* x; } x; x.__x = &__x; return ( x.x->exponent == 0x7ff && ( x.x->mantissah != 0 || x.x->mantissal != 0 )); } int _isnanl(long double __x) { /* Intel's extended format has the normally implicit 1 explicit present. Sigh! */ union { long double* __x; long_double_s* x; } x; x.__x = &__x; /* IEEE 854 NaN's have the maximum possible exponent and a nonzero mantissa. */ return (( x.x->exponent == 0x7fff) && ( (x.x->mantissah & 0x80000000) != 0) && ( (x.x->mantissah & (unsigned int)0x7fffffff) != 0 || x.x->mantissal != 0 )); } int _isinf(double __x) { union { double* __x; double_s* x; } x; x.__x = &__x; return ( x.x->exponent == 0x7ff && ( x.x->mantissah == 0 && x.x->mantissal == 0 )); } /* * @implemented */ int _finite( double x ) { return !_isinf(x); } int _isinfl(long double __x) { /* Intel's extended format has the normally implicit 1 explicit present. Sigh! */ union { long double* __x; long_double_s* x; } x; x.__x = &__x; /* An IEEE 854 infinity has an exponent with the maximum possible value and a zero mantissa. */ if ( x.x->exponent == 0x7fff && ( (x.x->mantissah == 0x80000000 ) && x.x->mantissal == 0 )) return x.x->sign ? -1 : 1; return 0; }