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// Boost.Signals2 library

// Copyright Frank Mori Hess 2007-2008.
// Use, modification and
// distribution is subject to the Boost Software License, Version
// 1.0. (See accompanying file LICENSE_1_0.txt or copy at

// For more information, see


#include <boost/shared_ptr.hpp>
#include <boost/signals2/connection.hpp>
#include <boost/weak_ptr.hpp>

namespace boost
  namespace signals2
    class shared_connection_block
      shared_connection_block(const signals2::connection &conn = signals2::connection(),
        bool initially_blocked = true):
        if(initially_blocked) block();
      void block()
        if(blocking()) return;
        boost::shared_ptr<detail::connection_body_base> connection_body(_weak_connection_body.lock());
        if(connection_body == 0)
          // Make _blocker non-empty so the blocking() method still returns the correct value
          // after the connection has expired.
        _blocker = connection_body->get_blocker();
      void unblock()
      bool blocking() const
        shared_ptr<void> empty;
        return _blocker < empty || empty < _blocker;
      signals2::connection connection() const
        return signals2::connection(_weak_connection_body);
      boost::weak_ptr<detail::connection_body_base> _weak_connection_body;
      shared_ptr<void> _blocker;
} // end namespace boost