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author | Thomas Guyot-Sionnest <dermoth@users.sourceforge.net> | 2008-02-12 12:03:58 +0000 |
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committer | Thomas Guyot-Sionnest <dermoth@users.sourceforge.net> | 2008-02-12 12:03:58 +0000 |
commit | abbad00edd7f5f3d33ae77a9d5ac338e5bea5fb3 (patch) | |
tree | 0d55fb4d8e5ad7a9376d1bccdea31104cbecacfe /gl/floor.c | |
parent | bd7029a99b0c2974265c6665638ef14a052f42ab (diff) | |
download | monitoring-plugins-abbad00edd7f5f3d33ae77a9d5ac338e5bea5fb3.tar.gz |
Import Gnulib floorf and base64 and removed our old base64 library.
git-svn-id: https://nagiosplug.svn.sourceforge.net/svnroot/nagiosplug/nagiosplug/trunk@1926 f882894a-f735-0410-b71e-b25c423dba1c
Diffstat (limited to 'gl/floor.c')
-rw-r--r-- | gl/floor.c | 93 |
1 files changed, 93 insertions, 0 deletions
diff --git a/gl/floor.c b/gl/floor.c new file mode 100644 index 00000000..05a6591a --- /dev/null +++ b/gl/floor.c | |||
@@ -0,0 +1,93 @@ | |||
1 | /* Round towards negative infinity. | ||
2 | Copyright (C) 2007 Free Software Foundation, Inc. | ||
3 | |||
4 | This program is free software: you can redistribute it and/or modify | ||
5 | it under the terms of the GNU General Public License as published by | ||
6 | the Free Software Foundation; either version 3 of the License, or | ||
7 | (at your option) any later version. | ||
8 | |||
9 | This program is distributed in the hope that it will be useful, | ||
10 | but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
12 | GNU General Public License for more details. | ||
13 | |||
14 | You should have received a copy of the GNU General Public License | ||
15 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ | ||
16 | |||
17 | /* Written by Bruno Haible <bruno@clisp.org>, 2007. */ | ||
18 | |||
19 | #include <config.h> | ||
20 | |||
21 | /* Specification. */ | ||
22 | #include <math.h> | ||
23 | |||
24 | #include <float.h> | ||
25 | |||
26 | #ifdef USE_LONG_DOUBLE | ||
27 | # define FUNC floorl | ||
28 | # define DOUBLE long double | ||
29 | # define MANT_DIG LDBL_MANT_DIG | ||
30 | # define L_(literal) literal##L | ||
31 | #elif ! defined USE_FLOAT | ||
32 | # define FUNC floor | ||
33 | # define DOUBLE double | ||
34 | # define MANT_DIG DBL_MANT_DIG | ||
35 | # define L_(literal) literal | ||
36 | #else /* defined USE_FLOAT */ | ||
37 | # define FUNC floorf | ||
38 | # define DOUBLE float | ||
39 | # define MANT_DIG FLT_MANT_DIG | ||
40 | # define L_(literal) literal##f | ||
41 | #endif | ||
42 | |||
43 | /* 2^(MANT_DIG-1). */ | ||
44 | static const DOUBLE TWO_MANT_DIG = | ||
45 | /* Assume MANT_DIG <= 5 * 31. | ||
46 | Use the identity | ||
47 | n = floor(n/5) + floor((n+1)/5) + ... + floor((n+4)/5). */ | ||
48 | (DOUBLE) (1U << ((MANT_DIG - 1) / 5)) | ||
49 | * (DOUBLE) (1U << ((MANT_DIG - 1 + 1) / 5)) | ||
50 | * (DOUBLE) (1U << ((MANT_DIG - 1 + 2) / 5)) | ||
51 | * (DOUBLE) (1U << ((MANT_DIG - 1 + 3) / 5)) | ||
52 | * (DOUBLE) (1U << ((MANT_DIG - 1 + 4) / 5)); | ||
53 | |||
54 | DOUBLE | ||
55 | FUNC (DOUBLE x) | ||
56 | { | ||
57 | /* The use of 'volatile' guarantees that excess precision bits are dropped | ||
58 | at each addition step and before the following comparison at the caller's | ||
59 | site. It is necessary on x86 systems where double-floats are not IEEE | ||
60 | compliant by default, to avoid that the results become platform and compiler | ||
61 | option dependent. 'volatile' is a portable alternative to gcc's | ||
62 | -ffloat-store option. */ | ||
63 | volatile DOUBLE y = x; | ||
64 | volatile DOUBLE z = y; | ||
65 | |||
66 | if (z > L_(0.0)) | ||
67 | { | ||
68 | /* Avoid rounding errors for values near 2^k, where k >= MANT_DIG-1. */ | ||
69 | if (z < TWO_MANT_DIG) | ||
70 | { | ||
71 | /* Round to the next integer (nearest or up or down, doesn't matter). */ | ||
72 | z += TWO_MANT_DIG; | ||
73 | z -= TWO_MANT_DIG; | ||
74 | /* Enforce rounding down. */ | ||
75 | if (z > y) | ||
76 | z -= L_(1.0); | ||
77 | } | ||
78 | } | ||
79 | else if (z < L_(0.0)) | ||
80 | { | ||
81 | /* Avoid rounding errors for values near -2^k, where k >= MANT_DIG-1. */ | ||
82 | if (z > - TWO_MANT_DIG) | ||
83 | { | ||
84 | /* Round to the next integer (nearest or up or down, doesn't matter). */ | ||
85 | z -= TWO_MANT_DIG; | ||
86 | z += TWO_MANT_DIG; | ||
87 | /* Enforce rounding down. */ | ||
88 | if (z > y) | ||
89 | z -= L_(1.0); | ||
90 | } | ||
91 | } | ||
92 | return z; | ||
93 | } | ||