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authorGravatar Thomas Guyot-Sionnest <dermoth@users.sourceforge.net> 2008-02-12 12:03:58 +0000
committerGravatar Thomas Guyot-Sionnest <dermoth@users.sourceforge.net> 2008-02-12 12:03:58 +0000
commitabbad00edd7f5f3d33ae77a9d5ac338e5bea5fb3 (patch)
tree0d55fb4d8e5ad7a9376d1bccdea31104cbecacfe /gl/floor.c
parentbd7029a99b0c2974265c6665638ef14a052f42ab (diff)
downloadmonitoring-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.c93
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 @@
+/* Round towards negative infinity.
+ Copyright (C) 2007 Free Software Foundation, Inc.
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program 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 General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
+
+/* Written by Bruno Haible <bruno@clisp.org>, 2007. */
+
+#include <config.h>
+
+/* Specification. */
+#include <math.h>
+
+#include <float.h>
+
+#ifdef USE_LONG_DOUBLE
+# define FUNC floorl
+# define DOUBLE long double
+# define MANT_DIG LDBL_MANT_DIG
+# define L_(literal) literal##L
+#elif ! defined USE_FLOAT
+# define FUNC floor
+# define DOUBLE double
+# define MANT_DIG DBL_MANT_DIG
+# define L_(literal) literal
+#else /* defined USE_FLOAT */
+# define FUNC floorf
+# define DOUBLE float
+# define MANT_DIG FLT_MANT_DIG
+# define L_(literal) literal##f
+#endif
+
+/* 2^(MANT_DIG-1). */
+static const DOUBLE TWO_MANT_DIG =
+ /* Assume MANT_DIG <= 5 * 31.
+ Use the identity
+ n = floor(n/5) + floor((n+1)/5) + ... + floor((n+4)/5). */
+ (DOUBLE) (1U << ((MANT_DIG - 1) / 5))
+ * (DOUBLE) (1U << ((MANT_DIG - 1 + 1) / 5))
+ * (DOUBLE) (1U << ((MANT_DIG - 1 + 2) / 5))
+ * (DOUBLE) (1U << ((MANT_DIG - 1 + 3) / 5))
+ * (DOUBLE) (1U << ((MANT_DIG - 1 + 4) / 5));
+
+DOUBLE
+FUNC (DOUBLE x)
+{
+ /* The use of 'volatile' guarantees that excess precision bits are dropped
+ at each addition step and before the following comparison at the caller's
+ site. It is necessary on x86 systems where double-floats are not IEEE
+ compliant by default, to avoid that the results become platform and compiler
+ option dependent. 'volatile' is a portable alternative to gcc's
+ -ffloat-store option. */
+ volatile DOUBLE y = x;
+ volatile DOUBLE z = y;
+
+ if (z > L_(0.0))
+ {
+ /* Avoid rounding errors for values near 2^k, where k >= MANT_DIG-1. */
+ if (z < TWO_MANT_DIG)
+ {
+ /* Round to the next integer (nearest or up or down, doesn't matter). */
+ z += TWO_MANT_DIG;
+ z -= TWO_MANT_DIG;
+ /* Enforce rounding down. */
+ if (z > y)
+ z -= L_(1.0);
+ }
+ }
+ else if (z < L_(0.0))
+ {
+ /* Avoid rounding errors for values near -2^k, where k >= MANT_DIG-1. */
+ if (z > - TWO_MANT_DIG)
+ {
+ /* Round to the next integer (nearest or up or down, doesn't matter). */
+ z -= TWO_MANT_DIG;
+ z += TWO_MANT_DIG;
+ /* Enforce rounding down. */
+ if (z > y)
+ z -= L_(1.0);
+ }
+ }
+ return z;
+}