Chris@16: // Boost.Signals2 library
Chris@16: 
Chris@16: // Copyright Frank Mori Hess 2007-2008.
Chris@16: // Use, modification and
Chris@16: // distribution is subject to the Boost Software License, Version
Chris@16: // 1.0. (See accompanying file LICENSE_1_0.txt or copy at
Chris@16: // http://www.boost.org/LICENSE_1_0.txt)
Chris@16: 
Chris@16: // For more information, see http://www.boost.org
Chris@16: 
Chris@16: #ifndef BOOST_SIGNALS2_SHARED_CONNECTION_BLOCK_HPP
Chris@16: #define BOOST_SIGNALS2_SHARED_CONNECTION_BLOCK_HPP
Chris@16: 
Chris@16: #include <boost/shared_ptr.hpp>
Chris@16: #include <boost/signals2/connection.hpp>
Chris@16: #include <boost/weak_ptr.hpp>
Chris@16: 
Chris@16: namespace boost
Chris@16: {
Chris@16:   namespace signals2
Chris@16:   {
Chris@16:     class shared_connection_block
Chris@16:     {
Chris@16:     public:
Chris@16:       shared_connection_block(const signals2::connection &conn = signals2::connection(),
Chris@16:         bool initially_blocked = true):
Chris@16:         _weak_connection_body(conn._weak_connection_body)
Chris@16:       {
Chris@16:         if(initially_blocked) block();
Chris@16:       }
Chris@16:       void block()
Chris@16:       {
Chris@16:         if(blocking()) return;
Chris@16:         boost::shared_ptr<detail::connection_body_base> connection_body(_weak_connection_body.lock());
Chris@16:         if(connection_body == 0)
Chris@16:         {
Chris@16:           // Make _blocker non-empty so the blocking() method still returns the correct value
Chris@16:           // after the connection has expired.
Chris@16:           _blocker.reset(static_cast<int*>(0));
Chris@16:           return;
Chris@16:         }
Chris@16:         _blocker = connection_body->get_blocker();
Chris@16:       }
Chris@16:       void unblock()
Chris@16:       {
Chris@16:         _blocker.reset();
Chris@16:       }
Chris@16:       bool blocking() const
Chris@16:       {
Chris@16:         shared_ptr<void> empty;
Chris@16:         return _blocker < empty || empty < _blocker;
Chris@16:       }
Chris@16:       signals2::connection connection() const
Chris@16:       {
Chris@16:         return signals2::connection(_weak_connection_body);
Chris@16:       }
Chris@16:     private:
Chris@16:       boost::weak_ptr<detail::connection_body_base> _weak_connection_body;
Chris@16:       shared_ptr<void> _blocker;
Chris@16:     };
Chris@16:   }
Chris@16: } // end namespace boost
Chris@16: 
Chris@16: #endif // BOOST_SIGNALS2_SHARED_CONNECTION_BLOCK_HPP