1 | /* Copyright (C) 2011-2016 Free Software Foundation, Inc. |
2 | This file is part of the GNU C Library. |
3 | Contributed by Ulrich Drepper <drepper@gmail.com>, 2011. |
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 | #include <fenv.h> |
20 | #include <math.h> |
21 | #include <math_private.h> |
22 | |
23 | |
24 | /* wrapper log10(x) */ |
25 | double |
26 | __log10 (double x) |
27 | { |
28 | if (__builtin_expect (islessequal (x, 0.0), 0) && _LIB_VERSION != _IEEE_) |
29 | { |
30 | if (x == 0.0) |
31 | { |
32 | __feraiseexcept (FE_DIVBYZERO); |
33 | return __kernel_standard (x, x, 18); /* log10(0) */ |
34 | } |
35 | else |
36 | { |
37 | __feraiseexcept (FE_INVALID); |
38 | return __kernel_standard (x, x, 19); /* log10(x<0) */ |
39 | } |
40 | } |
41 | |
42 | return __ieee754_log10 (x); |
43 | } |
44 | weak_alias (__log10, log10) |
45 | #ifdef NO_LONG_DOUBLE |
46 | strong_alias (__log10, __log10l) |
47 | weak_alias (__log10, log10l) |
48 | #endif |
49 | |