1 /* Wrapper to set errno for scalb. 2 Copyright (C) 2020-2022 Free Software Foundation, Inc. 3 This file is part of the GNU C Library. 4 5 The GNU C Library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Lesser General Public 7 License as published by the Free Software Foundation; either 8 version 2.1 of the License, or (at your option) any later version. 9 10 The GNU C Library is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public 16 License along with the GNU C Library; if not, see 17 <http://www.gnu.org/licenses/>. */ 18 19 /* Only build wrappers from the templates for the types that define the macro 20 below. This macro is set in math-type-macros-<type>.h in sysdeps/generic 21 for each floating-point type. */ 22 #if __USE_WRAPPER_TEMPLATE 23 24 #include <errno.h> 25 #include <math.h> 26 #include <math_private.h> 27 28 /* Wrapper scalb */ M_DECL_FUNC(__scalb)29FLOAT M_DECL_FUNC (__scalb) (FLOAT x, FLOAT fn) 30 { 31 FLOAT z = M_SUF (__ieee754_scalb) (x, fn); 32 33 if (__glibc_unlikely (!isfinite (z) || z == M_LIT (0.0))) 34 { 35 if (isnan (z)) 36 { 37 if (!isnan (x) && !isnan (fn)) 38 __set_errno (EDOM); 39 } 40 else if (isinf (z)) 41 { 42 if (!isinf (x) && !isinf (fn)) 43 __set_errno (ERANGE); 44 } 45 else 46 { 47 /* z == 0. */ 48 if (x != M_LIT (0.0) && !isinf (fn)) 49 __set_errno (ERANGE); 50 } 51 } 52 return z; 53 } 54 55 declare_mgen_alias (__scalb, scalb); 56 57 #endif /* __USE_WRAPPER_TEMPLATE. */ 58