shared_helpers.hpp

//
// Copyright 2014 Felix Petriconi
//
// License: http://boost.org/LICENSE_1_0.txt, Boost License 1.0
//
// Authors: http://petriconi.net, Felix Petriconi
//
#pragma once

#include <boost/thread.hpp>
#include <mutex>

namespace alb {
  inline namespace v_100 {
    namespace shared_helpers {

      class NullLock {
      public:
        explicit NullLock(boost::shared_mutex &) noexcept
        {
        }
      };

      class SharedLock {
        boost::shared_lock<boost::shared_mutex> _lock;

      public:
        explicit SharedLock(boost::shared_mutex &m) noexcept
          : _lock(m)
        {
        }
      };

      class UniqueLock {
        boost::unique_lock<boost::shared_mutex> _lock;

      public:
        explicit UniqueLock(boost::shared_mutex &m) noexcept
          : _lock(m)
        {
        }
      };

      struct null_mutex {
      };

      struct null_lock {
        explicit null_lock(null_mutex &) noexcept
        {
        }
      };

      template <class M> struct lock_guard;

      template <> struct lock_guard<null_mutex> {
        lock_guard(null_mutex &) noexcept
        {
        }
      };

      template <> struct lock_guard<std::mutex> {
        std::unique_lock<std::mutex> _lock;

      private:
        explicit lock_guard(std::mutex &m) noexcept
          : _lock(m)
        {
        }
      };

    } // namespace helpers
  }
  using namespace v_100;
} // namespace alb