WebSocket++  0.8.0-dev
C++ websocket client/server library
 All Classes Namespaces Files Functions Variables Typedefs Enumerations Enumerator Friends Pages
random_device.hpp
1 /*
2  * Copyright (c) 2014, Peter Thorson. All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions are met:
6  * * Redistributions of source code must retain the above copyright
7  * notice, this list of conditions and the following disclaimer.
8  * * Redistributions in binary form must reproduce the above copyright
9  * notice, this list of conditions and the following disclaimer in the
10  * documentation and/or other materials provided with the distribution.
11  * * Neither the name of the WebSocket++ Project nor the
12  * names of its contributors may be used to endorse or promote products
13  * derived from this software without specific prior written permission.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
16  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED. IN NO EVENT SHALL PETER THORSON BE LIABLE FOR ANY
19  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
20  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
21  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
22  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
24  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  *
26  */
27 
28 #ifndef WEBSOCKETPP_RANDOM_RANDOM_DEVICE_HPP
29 #define WEBSOCKETPP_RANDOM_RANDOM_DEVICE_HPP
30 
31 #include <websocketpp/common/random.hpp>
32 
33 namespace websocketpp {
34 namespace random {
35 /// RNG policy based on std::random_device or boost::random_device
36 namespace random_device {
37 
38 /// Thread safe non-deterministic random integer generator.
39 /**
40  * This template class provides thread safe non-deterministic random integer
41  * generation. Numbers are produced in a uniformly distributed range from the
42  * smallest to largest value that int_type can store.
43  *
44  * Thread-safety is provided via locking based on the concurrency template
45  * parameter.
46  *
47  * Non-deterministic RNG is provided via websocketpp::lib which uses either
48  * C++11 or Boost 1.47+'s random_device class.
49  *
50  * Call operator() to generate the next number
51  */
52 template <typename int_type, typename concurrency>
53 class int_generator {
54  public:
55  typedef typename concurrency::scoped_lock_type scoped_lock_type;
56  typedef typename concurrency::mutex_type mutex_type;
57 
58  /// constructor
59  //mac TODO: figure out if signed types present a range problem
61 
62  /// advances the engine's state and returns the generated value
63  int_type operator()() {
64  scoped_lock_type guard(m_lock);
65  return m_dis(m_rng);
66  }
67  private:
68 
69 
70  lib::random_device m_rng;
71  lib::uniform_int_distribution<int_type> m_dis;
72 
73  mutex_type m_lock;
74 };
75 
76 } // namespace random_device
77 } // namespace random
78 } // namespace websocketpp
79 
80 #endif //WEBSOCKETPP_RANDOM_RANDOM_DEVICE_HPP
Random number generation policies.
Definition: none.hpp:33
RNG policy based on std::random_device or boost::random_device.
int_type operator()()
advances the engine's state and returns the generated value
void handle_accept(connection_ptr con, lib::error_code const &ec)
Handler callback for start_accept.