Imported gcc-4.4.3

[msp430-gcc.git] / libstdc++-v3 / testsuite / util / testsuite_rng.h

diff --git a/libstdc++-v3/testsuite/util/testsuite_rng.h b/libstdc++-v3/testsuite/util/testsuite_rng.h
new file mode 100644 (file)
index 0000000..73b909e
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+++ b/libstdc++-v3/testsuite/util/testsuite_rng.h
@@ -0,0 +1,97 @@
+// -*- C++ -*-
+
+// Copyright (C) 2005, 2006, 2008, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library 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, or (at your option) any later
+// version.
+
+// This 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
+// General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+
+// Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
+
+// Permission to use, copy, modify, sell, and distribute this software
+// is hereby granted without fee, provided that the above copyright
+// notice appears in all copies, and that both that copyright notice
+// and this permission notice appear in supporting documentation. None
+// of the above authors, nor IBM Haifa Research Laboratories, make any
+// representation about the suitability of this software for any
+// purpose. It is provided "as is" without express or implied
+// warranty.
+
+/**
+ * @file testsuite_rng.h
+ */
+
+#ifndef _GLIBCXX_TESTSUITE_RNG_H
+#define _GLIBCXX_TESTSUITE_RNG_H
+
+#include <ctime>
+#include <climits>
+#include <debug/debug.h>
+#include <tr1/random>
+
+namespace __gnu_pbds
+{
+  namespace test
+  {
+    class twister_rand_gen
+    {
+    public:
+      twister_rand_gen(unsigned int seed = 
+                      static_cast<unsigned int>(std::time(0)))
+      : m_base_generator(seed)
+      {
+       // Do nothing.
+      }
+
+      void
+      init(unsigned int seed)
+      { m_base_generator.seed(seed); }
+
+      static unsigned int
+      get_time_determined_seed()
+      { return(static_cast<unsigned int>(std::time(0))); }
+
+      unsigned long
+      get_unsigned_long(unsigned long min = 0, 
+                       unsigned long max = UINT_MAX - 1)
+      {
+       _GLIBCXX_DEBUG_ASSERT(max >= min);
+       const double prob = get_prob();
+       const unsigned long r = (unsigned long)((max - min + 1) * prob) + min;
+       _GLIBCXX_DEBUG_ASSERT(r <= max);
+       return r;
+      }
+
+      double
+      get_prob()
+      {
+       const double min = m_base_generator.min();
+       const double max = m_base_generator.max();
+       const double range = static_cast<const double>(max - min);
+       const double res = static_cast<const double>(m_base_generator() - min);
+       const double ret = res / range;
+       _GLIBCXX_DEBUG_ASSERT(ret >= 0 && ret <= 1);
+       return ret;
+      }
+
+    private:
+      typedef std::tr1::mt19937 base_generator_t;
+
+      base_generator_t m_base_generator;
+    };
+  } // namespace test
+} // namespace __gnu_pbds
+
+#endif // #ifndef _GLIBCXX_TESTSUITE_RNG_H