boost/signals2/detail/tracked_objects_visitor.hpp
// Boost.Signals2 library
// Copyright Frank Mori Hess 2007-2008.
// Copyright Timmo Stange 2007.
// Copyright Douglas Gregor 2001-2004. Use, modification and
// distribution is subject to the Boost Software License, Version
// 1.0. (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
// For more information, see http://www.boost.org
#ifndef BOOST_SIGNALS2_TRACKED_OBJECTS_VISITOR_HPP
#define BOOST_SIGNALS2_TRACKED_OBJECTS_VISITOR_HPP
#include <boost/core/ref.hpp>
#include <boost/mpl/bool.hpp>
#include <boost/signals2/detail/signals_common.hpp>
#include <boost/signals2/slot_base.hpp>
#include <boost/signals2/trackable.hpp>
#include <boost/type_traits/is_function.hpp>
#include <boost/type_traits/is_pointer.hpp>
#include <boost/type_traits/remove_pointer.hpp>
#include <boost/core/addressof.hpp>
namespace boost
{
namespace signals2
{
namespace detail
{
// Visitor to collect tracked objects from a bound function.
class tracked_objects_visitor
{
public:
tracked_objects_visitor(slot_base *slot) : slot_(slot)
{}
template<typename T>
void operator()(const T& t) const
{
m_visit_reference_wrapper(t, mpl::bool_<is_reference_wrapper<T>::value>());
}
private:
template<typename T>
void m_visit_reference_wrapper(const reference_wrapper<T> &t, const mpl::bool_<true> &) const
{
m_visit_pointer(t.get_pointer(), mpl::bool_<true>());
}
template<typename T>
void m_visit_reference_wrapper(const T &t, const mpl::bool_<false> &) const
{
m_visit_pointer(t, mpl::bool_<is_pointer<T>::value>());
}
template<typename T>
void m_visit_pointer(const T &t, const mpl::bool_<true> &) const
{
m_visit_not_function_pointer(t, mpl::bool_<!is_function<typename remove_pointer<T>::type>::value>());
}
template<typename T>
void m_visit_pointer(const T &t, const mpl::bool_<false> &) const
{
m_visit_pointer(boost::addressof(t), mpl::bool_<true>());
}
template<typename T>
void m_visit_not_function_pointer(const T *t, const mpl::bool_<true> &) const
{
m_visit_signal(t, mpl::bool_<is_signal<T>::value>());
}
template<typename T>
void m_visit_not_function_pointer(const T &, const mpl::bool_<false> &) const
{}
template<typename T>
void m_visit_signal(const T *signal, const mpl::bool_<true> &) const
{
if(signal)
slot_->track_signal(*signal);
}
template<typename T>
void m_visit_signal(const T &t, const mpl::bool_<false> &) const
{
add_if_trackable(t);
}
void add_if_trackable(const trackable *trackable) const
{
if(trackable)
slot_->_tracked_objects.push_back(trackable->get_weak_ptr());
}
void add_if_trackable(const void *) const {}
mutable slot_base * slot_;
};
} // end namespace detail
} // end namespace signals2
} // end namespace boost
#endif // BOOST_SIGNALS2_TRACKED_OBJECTS_VISITOR_HPP