ceph/src/boost/boost/signals2/detail/tracked_objects_visitor.hpp

   1 // Boost.Signals2 library
   2
   3 // Copyright Frank Mori Hess 2007-2008.
   4 // Copyright Timmo Stange 2007.
   5 // Copyright Douglas Gregor 2001-2004. Use, modification and
   6 // distribution is subject to the Boost Software License, Version
   7 // 1.0. (See accompanying file LICENSE_1_0.txt or copy at
   8 // http://www.boost.org/LICENSE_1_0.txt)
   9
  10 // For more information, see http://www.boost.org
  11
  12 #ifndef BOOST_SIGNALS2_TRACKED_OBJECTS_VISITOR_HPP
  13 #define BOOST_SIGNALS2_TRACKED_OBJECTS_VISITOR_HPP
  14
  15 #include <boost/mpl/bool.hpp>
  16 #include <boost/ref.hpp>
  17 #include <boost/signals2/detail/signals_common.hpp>
  18 #include <boost/signals2/slot_base.hpp>
  19 #include <boost/signals2/trackable.hpp>
  20 #include <boost/type_traits/is_function.hpp>
  21 #include <boost/type_traits/is_pointer.hpp>
  22 #include <boost/type_traits/remove_pointer.hpp>
  23 #include <boost/utility/addressof.hpp>
  24
  25 namespace boost
  26 {
  27   namespace signals2
  28   {
  29     namespace detail
  30     {
  31       // Visitor to collect tracked objects from a bound function.
  32       class tracked_objects_visitor
  33       {
  34       public:
  35         tracked_objects_visitor(slot_base *slot) : slot_(slot)
  36         {}
  37         template<typename T>
  38         void operator()(const T& t) const
  39         {
  40             m_visit_reference_wrapper(t, mpl::bool_<is_reference_wrapper<T>::value>());
  41         }
  42       private:
  43         template<typename T>
  44         void m_visit_reference_wrapper(const reference_wrapper<T> &t, const mpl::bool_<true> &) const
  45         {
  46             m_visit_pointer(t.get_pointer(), mpl::bool_<true>());
  47         }
  48         template<typename T>
  49         void m_visit_reference_wrapper(const T &t, const mpl::bool_<false> &) const
  50         {
  51             m_visit_pointer(t, mpl::bool_<is_pointer<T>::value>());
  52         }
  53         template<typename T>
  54         void m_visit_pointer(const T &t, const mpl::bool_<true> &) const
  55         {
  56             m_visit_not_function_pointer(t, mpl::bool_<!is_function<typename remove_pointer<T>::type>::value>());
  57         }
  58         template<typename T>
  59         void m_visit_pointer(const T &t, const mpl::bool_<false> &) const
  60         {
  61             m_visit_pointer(boost::addressof(t), mpl::bool_<true>());
  62         }
  63         template<typename T>
  64         void m_visit_not_function_pointer(const T *t, const mpl::bool_<true> &) const
  65         {
  66             m_visit_signal(t, mpl::bool_<is_signal<T>::value>());
  67         }
  68         template<typename T>
  69         void m_visit_not_function_pointer(const T &, const mpl::bool_<false> &) const
  70         {}
  71         template<typename T>
  72         void m_visit_signal(const T *signal, const mpl::bool_<true> &) const
  73         {
  74           if(signal)
  75             slot_->track_signal(*signal);
  76         }
  77         template<typename T>
  78         void m_visit_signal(const T &t, const mpl::bool_<false> &) const
  79         {
  80             add_if_trackable(t);
  81         }
  82         void add_if_trackable(const trackable *trackable) const
  83         {
  84           if(trackable)
  85             slot_->_tracked_objects.push_back(trackable->get_weak_ptr());
  86         }
  87         void add_if_trackable(const void *) const {}
  88
  89         mutable slot_base * slot_;
  90       };
  91
  92
  93     } // end namespace detail
  94   } // end namespace signals2
  95 } // end namespace boost
  96
  97 #endif // BOOST_SIGNALS2_TRACKED_OBJECTS_VISITOR_HPP
  98