/* Wrapper to set errno for log2. Copyright (C) 2017 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, see <http://www.gnu.org/licenses/>. */ /* Only build wrappers from the templates for the types that define the macro below. This macro is set in math-type-macros-<type>.h in sysdeps/generic for each floating-point type. */ #if __USE_WRAPPER_TEMPLATE # include <errno.h> # include <fenv.h> # include <math.h> # include <math_private.h> FLOAT M_DECL_FUNC (__log2) (FLOAT x) { if (__glibc_unlikely (islessequal (x, M_LIT (0.0)))) { if (x == 0) /* Pole error: log2(0). */ __set_errno (ERANGE); else /* Domain error: log2(<0). */ __set_errno (EDOM); } return M_SUF (__ieee754_log2) (x); } declare_mgen_alias (__log2, log2) #endif /* __USE_WRAPPER_TEMPLATE. */