eqemu-server/libs/luabind/luabind/detail/instance_holder.hpp
2019-10-12 21:07:06 -07:00

132 lines
3.0 KiB
C++

// Copyright Daniel Wallin 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 http://www.boost.org/LICENSE_1_0.txt)
#ifndef LUABIND_INSTANCE_HOLDER_081024_HPP
# define LUABIND_INSTANCE_HOLDER_081024_HPP
# include <luabind/detail/inheritance.hpp>
# include <luabind/detail/class_rep.hpp> // TODO
# include <luabind/get_pointer.hpp>
# include <luabind/typeid.hpp>
# include <boost/type_traits/is_polymorphic.hpp>
# include <stdexcept>
namespace luabind { namespace detail {
class instance_holder
{
public:
instance_holder(class_rep* cls, bool pointee_const)
: m_cls(cls)
, m_pointee_const(pointee_const)
{}
virtual ~instance_holder()
{}
virtual std::pair<void*, int> get(class_id target) const = 0;
virtual void release() = 0;
class_rep* get_class() const
{
return m_cls;
}
bool pointee_const() const
{
return m_pointee_const;
}
private:
class_rep* m_cls;
bool m_pointee_const;
};
namespace mpl = boost::mpl;
inline mpl::false_ check_const_pointer(void*)
{
return mpl::false_();
}
inline mpl::true_ check_const_pointer(void const*)
{
return mpl::true_();
}
template <class T>
void release_ownership(std::auto_ptr<T>& p)
{
p.release();
}
template <class P>
void release_ownership(P const&)
{
throw std::runtime_error(
"luabind: smart pointer does not allow ownership transfer");
}
template <class T>
class_id static_class_id(T*)
{
return registered_class<T>::id;
}
template <class P, class Pointee = void const>
class pointer_holder : public instance_holder
{
public:
pointer_holder(
P p, class_id dynamic_id, void* dynamic_ptr, class_rep* cls
)
: instance_holder(cls, check_const_pointer(false ? get_pointer(p) : 0))
, p(p)
, weak(0)
, dynamic_id(dynamic_id)
, dynamic_ptr(dynamic_ptr)
{}
std::pair<void*, int> get(class_id target) const
{
if (target == registered_class<P>::id)
return std::pair<void*, int>(&this->p, 0);
void* naked_ptr = const_cast<void*>(static_cast<void const*>(
weak ? weak : get_pointer(p)));
if (!naked_ptr)
return std::pair<void*, int>((void*)0, 0);
return get_class()->casts().cast(
naked_ptr
, static_class_id(false ? get_pointer(p) : 0)
, target
, dynamic_id
, dynamic_ptr
);
}
void release()
{
weak = const_cast<void*>(static_cast<void const*>(
get_pointer(p)));
release_ownership(p);
}
private:
mutable P p;
// weak will hold a possibly stale pointer to the object owned
// by p once p has released it's owership. This is a workaround
// to make adopt() work with virtual function wrapper classes.
void* weak;
class_id dynamic_id;
void* dynamic_ptr;
};
}} // namespace luabind::detail
#endif // LUABIND_INSTANCE_HOLDER_081024_HPP