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: nondet_random.hpp,v 1.9 2004/07/27 03:43:27 dgregor Exp $

     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 <cmath>

    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 */