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Diffstat (limited to 'libstdc++-v3/testsuite/util/testsuite_rng.h')
-rw-r--r-- | libstdc++-v3/testsuite/util/testsuite_rng.h | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/libstdc++-v3/testsuite/util/testsuite_rng.h b/libstdc++-v3/testsuite/util/testsuite_rng.h new file mode 100644 index 00000000000..4cc076f13e2 --- /dev/null +++ b/libstdc++-v3/testsuite/util/testsuite_rng.h @@ -0,0 +1,107 @@ +// -*- C++ -*- + +// Copyright (C) 2005, 2006, 2008 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 2, 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 COPYING. If not, write to the Free +// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, +// USA. + +// As a special exception, you may use this file as part of a free +// software library without restriction. Specifically, if other files +// instantiate templates or use macros or inline functions from this +// file, or you compile this file and link it with other files to +// produce an executable, this file does not by itself cause the +// resulting executable to be covered by the GNU General Public +// License. This exception does not however invalidate any other +// reasons why the executable file might be covered by the GNU General +// Public License. + +// 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 |