Chris@16: // Boost.Signals library
Chris@16: 
Chris@16: // Copyright Douglas Gregor 2001-2004. 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_SIGNALS_TRACKABLE_HPP
Chris@16: #define BOOST_SIGNALS_TRACKABLE_HPP
Chris@16: 
Chris@16: #include <boost/type_traits.hpp>
Chris@16: #include <boost/signals/connection.hpp>
Chris@16: #include <boost/ref.hpp>
Chris@16: #include <boost/utility/addressof.hpp>
Chris@16: #include <list>
Chris@16: #include <vector>
Chris@16: 
Chris@16: #ifdef BOOST_HAS_ABI_HEADERS
Chris@16: #  include BOOST_ABI_PREFIX
Chris@16: #endif
Chris@16: 
Chris@16: namespace boost {
Chris@16: 
Chris@16: namespace BOOST_SIGNALS_NAMESPACE {
Chris@16:   // Base class for "trackable" objects that can be tracked when they are
Chris@16:   // bound in slot target functions. When a trackable object is destroyed,
Chris@16:   // the signal/slot connections are disconnected automatically.
Chris@16:   class BOOST_SIGNALS_DECL trackable {
Chris@16:   private:
Chris@16:     static void signal_disconnected(void* obj, void* data);
Chris@16: 
Chris@16:     friend class detail::signal_base_impl;
Chris@16:     friend class detail::slot_base;
Chris@16:     void signal_connected(connection, BOOST_SIGNALS_NAMESPACE::detail::bound_object&) const;
Chris@16: 
Chris@16:   protected:
Chris@16:     trackable() : connected_signals(), dying(false) {}
Chris@16:     trackable(const trackable&) : connected_signals(), dying(false) {}
Chris@16:     ~trackable();
Chris@16: 
Chris@16:     trackable& operator=(const trackable&)
Chris@16:     {
Chris@16:       dying = true;
Chris@16:       connected_signals.clear();
Chris@16:       dying = false;
Chris@16:       return *this;
Chris@16:     }
Chris@16: 
Chris@16:   private:
Chris@16:     typedef std::list<connection> connection_list;
Chris@16:     typedef connection_list::iterator connection_iterator;
Chris@16: 
Chris@16:     // List of connections that this object is part of
Chris@16:     mutable connection_list connected_signals;
Chris@16: 
Chris@16:     // True when the object is being destroyed
Chris@16:     mutable bool dying;
Chris@16:   };
Chris@16: 
Chris@16:   namespace detail {
Chris@16:     template<bool Cond> struct truth {};
Chris@16: 
Chris@16:     // A visitor that adds each trackable object to a vector
Chris@16:     class bound_objects_visitor {
Chris@16:     public:
Chris@16:       bound_objects_visitor(std::vector<const trackable*>& v) :
Chris@16:         bound_objects(v)
Chris@16:       {
Chris@16:       }
Chris@16: 
Chris@16:       template<typename T>
Chris@16:       void operator()(const T& t) const
Chris@16:       {
Chris@16:         decode(t, 0);
Chris@16:       }
Chris@16: 
Chris@16:     private:
Chris@16:       // decode() decides between a reference wrapper and anything else
Chris@16:       template<typename T>
Chris@16:       void decode(const reference_wrapper<T>& t, int) const
Chris@16:       {
Chris@16:         add_if_trackable(t.get_pointer());
Chris@16:       }
Chris@16: 
Chris@16:       template<typename T>
Chris@16:       void decode(const T& t, long) const
Chris@16:       {
Chris@16:         typedef truth<(is_pointer<T>::value)> is_a_pointer;
Chris@16:         maybe_get_pointer(t, is_a_pointer());
Chris@16:       }
Chris@16: 
Chris@16:       // maybe_get_pointer() decides between a pointer and a non-pointer
Chris@16:       template<typename T>
Chris@16:       void maybe_get_pointer(const T& t, truth<true>) const
Chris@16:       {
Chris@16:         add_if_trackable(t);
Chris@16:       }
Chris@16: 
Chris@16:       template<typename T>
Chris@16:       void maybe_get_pointer(const T& t, truth<false>) const
Chris@16:       {
Chris@16:         // Take the address of this object, because the object itself may be
Chris@16:         // trackable
Chris@16:         add_if_trackable(boost::addressof(t));
Chris@16:       }
Chris@16: 
Chris@16:       // add_if_trackable() adds trackable objects to the list of bound objects
Chris@16:       inline void add_if_trackable(const trackable* b) const
Chris@16:       {
Chris@16:         if (b) {
Chris@16:           bound_objects.push_back(b);
Chris@16:         }
Chris@16:       }
Chris@16: 
Chris@16:       inline void add_if_trackable(const void*) const { }
Chris@16: 
Chris@16:       template<typename R>
Chris@16:       inline void add_if_trackable(R (*)()) const { }
Chris@16: 
Chris@16:       template<typename R, typename T1>
Chris@16:       inline void add_if_trackable(R (*)(T1)) const { }
Chris@16: 
Chris@16:       template<typename R, typename T1, typename T2>
Chris@16:       inline void add_if_trackable(R (*)(T1, T2)) const { }
Chris@16: 
Chris@16:       template<typename R, typename T1, typename T2, typename T3>
Chris@16:       inline void add_if_trackable(R (*)(T1, T2, T3)) const { }
Chris@16: 
Chris@16:       template<typename R, typename T1, typename T2, typename T3, typename T4>
Chris@16:       inline void add_if_trackable(R (*)(T1, T2, T3, T4)) const { }
Chris@16: 
Chris@16:       template<typename R, typename T1, typename T2, typename T3, typename T4,
Chris@16:                typename T5>
Chris@16:       inline void add_if_trackable(R (*)(T1, T2, T3, T4, T5)) const { }
Chris@16: 
Chris@16:       template<typename R, typename T1, typename T2, typename T3, typename T4,
Chris@16:                typename T5, typename T6>
Chris@16:       inline void add_if_trackable(R (*)(T1, T2, T3, T4, T5, T6)) const { }
Chris@16: 
Chris@16:       template<typename R, typename T1, typename T2, typename T3, typename T4,
Chris@16:                typename T5, typename T6, typename T7>
Chris@16:       inline void add_if_trackable(R (*)(T1, T2, T3, T4, T5, T6, T7)) const { }
Chris@16: 
Chris@16:       template<typename R, typename T1, typename T2, typename T3, typename T4,
Chris@16:                typename T5, typename T6, typename T7, typename T8>
Chris@16:       inline void 
Chris@16:       add_if_trackable(R (*)(T1, T2, T3, T4, T5, T6, T7, T8)) const { }
Chris@16: 
Chris@16:       template<typename R, typename T1, typename T2, typename T3, typename T4,
Chris@16:                typename T5, typename T6, typename T7, typename T8, typename T9>
Chris@16:       inline void
Chris@16:       add_if_trackable(R (*)(T1, T2, T3, T4, T5, T6, T7, T8, T9)) const { }
Chris@16: 
Chris@16:       template<typename R, typename T1, typename T2, typename T3, typename T4,
Chris@16:                typename T5, typename T6, typename T7, typename T8, typename T9,
Chris@16:                typename T10>
Chris@16:       inline void
Chris@16:       add_if_trackable(R (*)(T1, T2, T3, T4, T5, T6, T7, T8, T9, T10)) const { }
Chris@16: 
Chris@16:       std::vector<const trackable*>& bound_objects;
Chris@16:     };
Chris@16:   } // end namespace detail
Chris@16: } // end namespace BOOST_SIGNALS_NAMESPACE
Chris@16: 
Chris@16: } // end namespace boost
Chris@16: 
Chris@16: #ifdef BOOST_HAS_ABI_HEADERS
Chris@16: #  include BOOST_ABI_SUFFIX
Chris@16: #endif
Chris@16: 
Chris@16: #endif // BOOST_SIGNALS_TRACKABLE_HPP