Chris@16: // Copyright (C) 2000 Stephen Cleary
Chris@16: //
Chris@16: // Distributed under the Boost Software License, Version 1.0. (See
Chris@16: // accompanying file LICENSE_1_0.txt or copy at
Chris@16: // http://www.boost.org/LICENSE_1_0.txt)
Chris@16: //
Chris@16: // See http://www.boost.org for updates, documentation, and revision history.
Chris@16: 
Chris@16: #ifndef BOOST_POOL_GUARD_HPP
Chris@16: #define BOOST_POOL_GUARD_HPP
Chris@16: 
Chris@16: /*!
Chris@16:   \file
Chris@16:   \brief Extremely Light-Weight guard class.
Chris@16:   \details Auto-lock/unlock-er
Chris@16:   detail/guard.hpp provides a type guard<Mutex>
Chris@16:   that allows scoped access to the Mutex's locking and unlocking operations.
Chris@16:   It is used to ensure that a Mutex is unlocked, even if an exception is thrown.
Chris@16: */
Chris@16: 
Chris@16: namespace boost {
Chris@16: 
Chris@16: namespace details {
Chris@16: namespace pool {
Chris@16: 
Chris@16: template <typename Mutex> //!< \tparam Mutex (platform-specific) mutex class.
Chris@16: class guard
Chris@16: { //! Locks the mutex, binding guard<Mutex> to Mutex.
Chris@16: 	/*! Example:
Chris@16: 	Given a (platform-specific) mutex class, we can wrap code as follows:
Chris@16: 
Chris@16: 	extern mutex global_lock;
Chris@16: 
Chris@16: 	static void f()
Chris@16: 	{
Chris@16: 		boost::details::pool::guard<mutex> g(global_lock);
Chris@16: 		// g's constructor locks "global_lock"
Chris@16: 
Chris@16: 		... // do anything:
Chris@16: 				//   throw exceptions
Chris@16: 				//   return
Chris@16: 				//   or just fall through
Chris@16: 	} // g's destructor unlocks "global_lock"
Chris@16: 	*/
Chris@16:   private:
Chris@16:     Mutex & mtx;
Chris@16: 
Chris@16:     guard(const guard &); //!< Guards the mutex, ensuring unlocked on destruction, even if exception is thrown.
Chris@16:     void operator=(const guard &);
Chris@16: 
Chris@16:   public:
Chris@16:     explicit guard(Mutex & nmtx)
Chris@16:     :mtx(nmtx)
Chris@16:     { //! Locks the mutex of the guard class.
Chris@16: 			mtx.lock();
Chris@16: 		}
Chris@16: 
Chris@16:     ~guard()
Chris@16:     { //! destructor unlocks the mutex of the guard class.
Chris@16: 			mtx.unlock();
Chris@16: 		}
Chris@16: }; // class guard
Chris@16: 
Chris@16: } // namespace pool
Chris@16: } // namespace details
Chris@16: 
Chris@16: } // namespace boost
Chris@16: 
Chris@16: #endif