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Diffstat (limited to 'websocketpp/random/random_device.hpp')
-rw-r--r-- | websocketpp/random/random_device.hpp | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/websocketpp/random/random_device.hpp b/websocketpp/random/random_device.hpp new file mode 100644 index 00000000..91e7dd16 --- /dev/null +++ b/websocketpp/random/random_device.hpp @@ -0,0 +1,80 @@ +/* + * Copyright (c) 2014, Peter Thorson. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * * Neither the name of the WebSocket++ Project nor the + * names of its contributors may be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL PETER THORSON BE LIABLE FOR ANY + * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES + * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; + * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND + * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS + * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + */ + +#ifndef WEBSOCKETPP_RANDOM_RANDOM_DEVICE_HPP +#define WEBSOCKETPP_RANDOM_RANDOM_DEVICE_HPP + +#include <websocketpp/common/random.hpp> + +namespace websocketpp { +namespace random { +/// RNG policy based on std::random_device or boost::random_device +namespace random_device { + +/// Thread safe non-deterministic random integer generator. +/** + * This template class provides thread safe non-deterministic random integer + * generation. Numbers are produced in a uniformly distributed range from the + * smallest to largest value that int_type can store. + * + * Thread-safety is provided via locking based on the concurrency template + * parameter. + * + * Non-deterministic RNG is provided via websocketpp::lib which uses either + * C++11 or Boost 1.47+'s random_device class. + * + * Call operator() to generate the next number + */ +template <typename int_type, typename concurrency> +class int_generator { + public: + typedef typename concurrency::scoped_lock_type scoped_lock_type; + typedef typename concurrency::mutex_type mutex_type; + + /// constructor + //mac TODO: figure out if signed types present a range problem + int_generator() {} + + /// advances the engine's state and returns the generated value + int_type operator()() { + scoped_lock_type guard(m_lock); + return m_dis(m_rng); + } + private: + + + lib::random_device m_rng; + lib::uniform_int_distribution<int_type> m_dis; + + mutex_type m_lock; +}; + +} // namespace random_device +} // namespace random +} // namespace websocketpp + +#endif //WEBSOCKETPP_RANDOM_RANDOM_DEVICE_HPP |