eqemu-server/libs/luabind/luabind/detail/class_rep.hpp

// Copyright (c) 2003 Daniel Wallin and Arvid Norberg

// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following conditions:

// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.

// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
// ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
// TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
// PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
// SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
// ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
// ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE
// OR OTHER DEALINGS IN THE SOFTWARE.


#ifndef LUABIND_CLASS_REP_HPP_INCLUDED
#define LUABIND_CLASS_REP_HPP_INCLUDED

#include <string>
#include <utility>
#include <vector>

#include <luabind/config.hpp>
#include <luabind/lua_include.hpp>
#include <luabind/detail/garbage_collector.hpp>
#include <luabind/detail/operator_id.hpp>
#include <luabind/detail/class_registry.hpp>
#include <luabind/error.hpp>
#include <luabind/handle.hpp>
#include <luabind/detail/primitives.hpp>
#include <luabind/typeid.hpp>
#include <luabind/detail/ref.hpp>

namespace luabind {
	namespace detail {

		LUABIND_API std::string stack_content_by_name(lua_State* L, int start_index);

		struct class_registration;

		struct conversion_storage;

		// This function is used as a tag to identify "properties".
		LUABIND_API int property_tag(lua_State*);

		// this is class-specific information, poor man's vtable
		// this is allocated statically (removed by the compiler)
		// a pointer to this structure is stored in the lua tables'
		// metatable with the name __classrep
		// it is used when matching parameters to function calls
		// to determine possible implicit casts
		// it is also used when finding the best match for overloaded
		// methods

		class cast_graph;
		class class_id_map;

		class LUABIND_API class_rep
		{
			friend struct class_registration;
			friend int super_callback(lua_State*);
			//TODO: avoid the lua-prefix
			friend int lua_class_gettable(lua_State*);
			friend int lua_class_settable(lua_State*);
			friend int static_class_gettable(lua_State*);
		public:

			enum class_type
			{
				cpp_class = 0,
				lua_class = 1
			};

			// EXPECTS THE TOP VALUE ON THE LUA STACK TO
			// BE THE USER DATA WHERE THIS CLASS IS BEING
			// INSTANTIATED!
			class_rep(type_id const& type
				, const char* name
				, lua_State* L
			);

			// used when creating a lua class
			// EXPECTS THE TOP VALUE ON THE LUA STACK TO
			// BE THE USER DATA WHERE THIS CLASS IS BEING
			// INSTANTIATED!
			class_rep(lua_State* L, const char* name);

			~class_rep();

			std::pair<void*, void*> allocate(lua_State* L) const;

			// this is called as metamethod __call on the class_rep.
			static int constructor_dispatcher(lua_State* L);

			struct base_info
			{
				int pointer_offset; // the offset added to the pointer to obtain a basepointer (due to multiple-inheritance)
				class_rep* base;
			};

			void add_base_class(const base_info& binfo);

			const std::vector<base_info>& bases() const throw() { return m_bases; }

			void set_type(type_id const& t) { m_type = t; }
			type_id const& type() const throw() { return m_type; }

			const char* name() const throw() { return m_name; }

			// the lua reference to the metatable for this class' instances
			int metatable_ref() const throw() { return m_instance_metatable; }

			void get_table(lua_State* L) const { m_table.push(L); }
			void get_default_table(lua_State* L) const { m_default_table.push(L); }

			class_type get_class_type() const { return m_class_type; }

			void add_static_constant(const char* name, int val);

			static int super_callback(lua_State* L);

			static int lua_settable_dispatcher(lua_State* L);

			// called from the metamethod for __index
			// obj is the object pointer
			static int static_class_gettable(lua_State* L);

			bool has_operator_in_lua(lua_State*, int id);

			cast_graph const& casts() const
			{
				return *m_casts;
			}

			class_id_map const& classes() const
			{
				return *m_classes;
			}

		private:

			// Code common to both constructors
			void shared_init(lua_State * L);

			void cache_operators(lua_State*);

			// this is a pointer to the type_info structure for
			// this type
			// warning: this may be a problem when using dll:s, since
			// typeid() may actually return different pointers for the same
			// type.
			type_id m_type;

			// a list of info for every class this class derives from
			// the information stored here is sufficient to do
			// type casts to the base classes
			std::vector<base_info> m_bases;

			// the class' name (as given when registered to lua with class_)
			const char* m_name;

			// a reference to this structure itself. Since this struct
			// is kept inside lua (to let lua collect it when lua_close()
			// is called) we need to lock it to prevent collection.
			// the actual reference is not currently used.
			detail::lua_reference m_self_ref;

			// this should always be used when accessing
			// members in instances of a class.
			// this table contains c closures for all
			// member functions in this class, they
			// may point to both static and virtual functions
			handle m_table;

			// this table contains default implementations of the
			// virtual functions in m_table.
			handle m_default_table;

			// the type of this class.. determines if it's written in c++ or lua
			class_type m_class_type;

			// this is a lua reference that points to the lua table
			// that is to be used as meta table for all instances
			// of this class.
			int m_instance_metatable;

			std::map<const char*, int, ltstr> m_static_constants;

			// the first time an operator is invoked
			// we check the associated lua table
			// and cache the result
			int m_operator_cache;

			cast_graph* m_casts;
			class_id_map* m_classes;
		};

		LUABIND_API bool is_class_rep(lua_State* L, int index);

	}
}

#endif // LUABIND_CLASS_REP_HPP_INCLUDED