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-rw-r--r--stdlib/erand48_r.c52
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diff --git a/stdlib/erand48_r.c b/stdlib/erand48_r.c
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+/* Copyright (C) 1995 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, August 1995.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library 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
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA.  */
+
+#include <errno.h>
+#include <math.h>
+#include <stdlib.h>
+
+int
+erand48_r (xsubi, buffer, result)
+     unsigned short int xsubi[3];
+     struct drand48_data *buffer;
+     double *result;
+{
+  int i;
+
+  /* Be generous for the arguments, detect some errors.  */
+  if (result == NULL)
+    {
+      errno = EFAULT;
+      return -1;
+    }
+
+  /* Compute next state.  */
+  if (__drand48_iterate (xsubi, buffer) < 0)
+    return -1;
+
+  *result = 0.0;
+  for (i = 4 / sizeof (unsigned short int); i >= 0; --i)
+    {
+      double factor = ldexp (1.0, (i - 6) * sizeof (unsigned short int));
+
+      *result += factor * (double) xsubi[i];
+    }
+
+  return 0;
+}