/*****************************************************************************
- * nrand48.c: POSIX nrand48() replacement
+ * nrand48.c: POSIX erand48(), jrand48() and nrand48() replacements
*****************************************************************************
* Copyright © 2010 Rémi Denis-Courmont
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU Lesser General Public License as published
- * by the Free Software Foundation; either version 2.1 of the License, or
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 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.
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
*****************************************************************************/
#ifdef HAVE_CONFIG_H
#include <inttypes.h>
-long nrand48 (unsigned short subi[3])
+static uint64_t iterate48 (unsigned short subi[3])
{
const uint64_t a = UINT64_C(0x5DEECE66D);
const unsigned c = 13;
subi[1] = (x >> 16) & 0xFFFF;
subi[2] = (x >> 0) & 0XFFFF;
- return x >> 17;
+ return x;
+}
+
+double erand48 (unsigned short subi[3])
+{
+ uint64_t r = iterate48 (subi);
+ return ((double)r) / 281474976710655.;
+}
+
+long jrand48 (unsigned short subi[3])
+{
+ return ((int64_t)iterate48 (subi)) >> 16;
+}
+
+long nrand48 (unsigned short subi[3])
+{
+ return iterate48 (subi) >> 17;
}