boost/nondet_random.hpp

   1 /* boost nondet_random.hpp header file
   2  *
   3  * Copyright Jens Maurer 2000
   4  * Distributed under the Boost Software License, Version 1.0. (See
   5  * accompanying file LICENSE_1_0.txt or copy at
   6  * http://www.boost.org/LICENSE_1_0.txt)
   7  *
   8  * $Id$
   9  *
  10  * Revision history
  11  *  2000-02-18  Portability fixes (thanks to Beman Dawes)
  12  */
  13
  14 //  See http://www.boost.org/libs/random for documentation.
  15
  16
  17 #ifndef BOOST_NONDET_RANDOM_HPP
  18 #define BOOST_NONDET_RANDOM_HPP
  19
  20 #include <string>                       // std::abs
  21 #include <algorithm>                    // std::min
  22 #include <boost/config/no_tr1/cmath.hpp>
  23 #include <boost/config.hpp>
  24 #include <boost/utility.hpp>            // noncopyable
  25 #include <boost/integer_traits.hpp>     // compile-time integral limits
  26
  27 namespace boost {
  28
  29 // use some OS service to generate non-deterministic random numbers
  30 class random_device : private noncopyable
  31 {
  32 public:
  33   typedef unsigned int result_type;
  34   BOOST_STATIC_CONSTANT(bool, has_fixed_range = true);
  35   BOOST_STATIC_CONSTANT(result_type, min_value = integer_traits<result_type>::const_min);
  36   BOOST_STATIC_CONSTANT(result_type, max_value = integer_traits<result_type>::const_max);
  37
  38   result_type min BOOST_PREVENT_MACRO_SUBSTITUTION () const { return min_value; }
  39   result_type max BOOST_PREVENT_MACRO_SUBSTITUTION () const { return max_value; }
  40   explicit random_device(const std::string& token = default_token);
  41   ~random_device();
  42   double entropy() const;
  43   unsigned int operator()();
  44
  45 private:
  46   static const char * const default_token;
  47
  48   /*
  49    * std:5.3.5/5 [expr.delete]: "If the object being deleted has incomplete
  50    * class type at the point of deletion and the complete class has a
  51    * non-trivial destructor [...], the behavior is undefined".
  52    * This disallows the use of scoped_ptr<> with pimpl-like classes
  53    * having a non-trivial destructor.
  54    */
  55   class impl;
  56   impl * pimpl;
  57 };
  58
  59
  60 // TODO: put Schneier's Yarrow-160 algorithm here.
  61
  62 } // namespace boost
  63
  64 #endif /* BOOST_NONDET_RANDOM_HPP */