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 */
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
55declare_mgen_alias (__scalb, scalb);
56
57#endif /* __USE_WRAPPER_TEMPLATE. */
58

source code of glibc/math/w_scalb_template.c