sl@0: // Boost.Signals library
sl@0: 
sl@0: // Copyright Douglas Gregor 2001-2004. Use, modification and
sl@0: // distribution is subject to the Boost Software License, Version
sl@0: // 1.0. (See accompanying file LICENSE_1_0.txt or copy at
sl@0: // http://www.boost.org/LICENSE_1_0.txt)
sl@0: 
sl@0: // For more information, see http://www.boost.org
sl@0: 
sl@0: #ifndef BOOST_SIGNALS_CONNECTION_HPP
sl@0: #define BOOST_SIGNALS_CONNECTION_HPP
sl@0: 
sl@0: #include <boost/signals/detail/signals_common.hpp>
sl@0: #include <boost/smart_ptr.hpp>
sl@0: #include <boost/operators.hpp>
sl@0: #include <boost/any.hpp>
sl@0: #include <list>
sl@0: #include <cassert>
sl@0: #include <utility>
sl@0: 
sl@0: #ifdef BOOST_HAS_ABI_HEADERS
sl@0: #  include BOOST_ABI_PREFIX
sl@0: #endif
sl@0: 
sl@0: namespace boost {
sl@0:   namespace BOOST_SIGNALS_NAMESPACE {
sl@0:     class trackable;
sl@0: 
sl@0:     namespace detail {
sl@0:       // Represents an object that has been bound as part of a slot, and how
sl@0:       // to notify that object of a disconnect
sl@0:       struct bound_object {
sl@0:         void* obj;
sl@0:         void* data;
sl@0:         void (*disconnect)(void*, void*);
sl@0: 
sl@0:         bool operator==(const bound_object& other) const
sl@0:           { return obj == other.obj && data == other.data; }
sl@0:         bool operator<(const bound_object& other) const
sl@0:           { return obj < other.obj; }
sl@0: 
sl@0:         // To support intel 80 compiler, 2004/03/18 (Mark Rodgers)
sl@0:         bool operator!=(const bound_object& other) const
sl@0:         { return !(*this==other); }
sl@0:         bool operator>(const bound_object& other) const
sl@0:         { return !(*this < other); }
sl@0:       };
sl@0: 
sl@0:       // Describes the connection between a signal and the objects that are
sl@0:       // bound for a specific slot. Enables notification of the signal and the
sl@0:       // slots when a disconnect is requested.
sl@0:       struct basic_connection {
sl@0:         void* signal;
sl@0:         void* signal_data;
sl@0:         void (*signal_disconnect)(void*, void*);
sl@0:         bool blocked_;
sl@0: 
sl@0:         std::list<bound_object> bound_objects;
sl@0:       };
sl@0:     } // end namespace detail
sl@0: 
sl@0:     // The user may freely pass around the "connection" object and terminate
sl@0:     // the connection at any time using disconnect().
sl@0:     class BOOST_SIGNALS_DECL connection :
sl@0:       private less_than_comparable1<connection>,
sl@0:       private equality_comparable1<connection>
sl@0:     {
sl@0:     public:
sl@0:       connection() : con(), controlling_connection(false) {}
sl@0:       connection(const connection&);
sl@0:       ~connection();
sl@0: 
sl@0:       // Block he connection: if the connection is still active, there
sl@0:       // will be no notification
sl@0:       void block(bool should_block = true) { con->blocked_ = should_block; }
sl@0:       void unblock() { con->blocked_ = false; }
sl@0:       bool blocked() const { return !connected() || con->blocked_; }
sl@0: 
sl@0:       // Disconnect the signal and slot, if they are connected
sl@0:       void disconnect() const;
sl@0: 
sl@0:       // Returns true if the signal and slot are connected
sl@0:       bool connected() const { return con.get() && con->signal_disconnect; }
sl@0: 
sl@0:       // Comparison of connections
sl@0:       bool operator==(const connection& other) const;
sl@0:       bool operator<(const connection& other) const;
sl@0: 
sl@0:       // Connection assignment
sl@0:       connection& operator=(const connection& other) ;
sl@0: 
sl@0:       // Swap connections
sl@0:       void swap(connection& other);
sl@0: 
sl@0:     public: // TBD: CHANGE THIS
sl@0:       // Set whether this connection object is controlling or not
sl@0:       void set_controlling(bool control = true)
sl@0:       { controlling_connection = control; }
sl@0: 
sl@0:       shared_ptr<BOOST_SIGNALS_NAMESPACE::detail::basic_connection>
sl@0:       get_connection() const
sl@0:       { return con; }
sl@0: 
sl@0:     private:
sl@0:       friend class detail::signal_base_impl;
sl@0:       friend class detail::slot_base;
sl@0:       friend class trackable;
sl@0: 
sl@0:       // Reset this connection to refer to a different actual connection
sl@0:       void reset(BOOST_SIGNALS_NAMESPACE::detail::basic_connection*);
sl@0: 
sl@0:       // Add a bound object to this connection (not for users)
sl@0:       void add_bound_object(const BOOST_SIGNALS_NAMESPACE::detail::bound_object& b);
sl@0: 
sl@0:       friend class BOOST_SIGNALS_NAMESPACE::detail::bound_objects_visitor;
sl@0: 
sl@0:       // Pointer to the actual contents of the connection
sl@0:       shared_ptr<BOOST_SIGNALS_NAMESPACE::detail::basic_connection> con;
sl@0: 
sl@0:       // True if the destruction of this connection object should disconnect
sl@0:       bool controlling_connection;
sl@0:     };
sl@0: 
sl@0:     // Similar to connection, but will disconnect the connection when it is
sl@0:     // destroyed unless release() has been called.
sl@0:     class BOOST_SIGNALS_DECL scoped_connection : public connection {
sl@0:     public:
sl@0:       scoped_connection() : connection(), released(false) {}
sl@0:       scoped_connection(const connection&);
sl@0:       scoped_connection(const scoped_connection&);
sl@0:       ~scoped_connection();
sl@0: 
sl@0:       connection release();
sl@0: 
sl@0:       inline void swap(scoped_connection&);
sl@0: 
sl@0:       scoped_connection& operator=(const connection&);
sl@0:       scoped_connection& operator=(const scoped_connection&);
sl@0: 
sl@0:     private:
sl@0:       bool released;
sl@0:     };
sl@0: 
sl@0:     namespace detail {
sl@0:       struct connection_slot_pair {
sl@0:         connection first;
sl@0:         any second;
sl@0: 
sl@0:         connection_slot_pair() {}
sl@0: 
sl@0:         connection_slot_pair(const connection& c, const any& a)
sl@0:           : first(c), second(a)
sl@0:         {
sl@0:         }
sl@0: 
sl@0:         // Dummys to allow explicit instantiation to work
sl@0:         bool operator==(const connection_slot_pair&) const { return false; }
sl@0:         bool operator<(const connection_slot_pair&) const { return false;}
sl@0:       };
sl@0: 
sl@0:       // Determines if the underlying connection is disconnected
sl@0:       struct is_disconnected {
sl@0:         typedef connection_slot_pair argument_type;
sl@0:         typedef bool result_type;
sl@0: 
sl@0:         inline bool operator()(const argument_type& c) const
sl@0:         {
sl@0:           return !c.first.connected();
sl@0:         }
sl@0:       };
sl@0: 
sl@0:       // Determines if the underlying connection is callable, ie if
sl@0:       // it is connected and not blocked
sl@0:       struct is_callable {
sl@0:         typedef connection_slot_pair argument_type;
sl@0:         typedef bool result_type;
sl@0: 
sl@0:         inline bool operator()(const argument_type& c) const
sl@0:         {
sl@0:           return c.first.connected() && !c.first.blocked() ;
sl@0:         }
sl@0:       };
sl@0: 
sl@0:       // Autodisconnects the bound object when it is destroyed unless the
sl@0:       // release method is invoked.
sl@0:       class auto_disconnect_bound_object {
sl@0:       public:
sl@0:         auto_disconnect_bound_object(const bound_object& b) :
sl@0:           binding(b), auto_disconnect(true)
sl@0:         {
sl@0:         }
sl@0: 
sl@0:         ~auto_disconnect_bound_object()
sl@0:         {
sl@0:           if (auto_disconnect)
sl@0:             binding.disconnect(binding.obj, binding.data);
sl@0:         }
sl@0: 
sl@0:         void release() { auto_disconnect = false; }
sl@0: 
sl@0:       private:
sl@0:         bound_object binding;
sl@0:         bool auto_disconnect;
sl@0:       };
sl@0:     } // end namespace detail
sl@0:   } // end namespace BOOST_SIGNALS_NAMESPACE
sl@0: } // end namespace boost
sl@0: 
sl@0: #ifdef BOOST_HAS_ABI_HEADERS
sl@0: #  include BOOST_ABI_SUFFIX
sl@0: #endif
sl@0: 
sl@0: #endif // BOOST_SIGNALS_CONNECTION_HPP