luabind/detail/class_rep.hpp

   1 // Copyright (c) 2003 Daniel Wallin and Arvid Norberg
   2
   3 // Permission is hereby granted, free of charge, to any person obtaining a
   4 // copy of this software and associated documentation files (the "Software"),
   5 // to deal in the Software without restriction, including without limitation
   6 // the rights to use, copy, modify, merge, publish, distribute, sublicense,
   7 // and/or sell copies of the Software, and to permit persons to whom the
   8 // Software is furnished to do so, subject to the following conditions:
   9
  10 // The above copyright notice and this permission notice shall be included
  11 // in all copies or substantial portions of the Software.
  12
  13 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
  14 // ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
  15 // TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
  16 // PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
  17 // SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
  18 // ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  19 // ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  20 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE
  21 // OR OTHER DEALINGS IN THE SOFTWARE.
  22
  23
  24 #ifndef LUABIND_CLASS_REP_HPP_INCLUDED
  25 #define LUABIND_CLASS_REP_HPP_INCLUDED
  26
  27 #include <boost/limits.hpp>
  28 #include <boost/preprocessor/repetition/enum_params_with_a_default.hpp>
  29
  30 #include <string>
  31 #include <utility>
  32 #include <vector>
  33
  34 #include <luabind/config.hpp>
  35 #include <luabind/lua_include.hpp>
  36 #include <luabind/detail/object_rep.hpp>
  37 #include <luabind/detail/garbage_collector.hpp>
  38 #include <luabind/detail/operator_id.hpp>
  39 #include <luabind/detail/class_registry.hpp>
  40 #include <luabind/error.hpp>
  41 #include <luabind/handle.hpp>
  42 #include <luabind/detail/primitives.hpp>
  43 #include <luabind/typeid.hpp>
  44 #include <luabind/detail/ref.hpp>
  45
  46 namespace luabind { namespace detail
  47 {
  48
  49         LUABIND_API std::string stack_content_by_name(lua_State* L, int start_index);
  50
  51         struct class_registration;
  52
  53         struct conversion_storage;
  54
  55         // This function is used as a tag to identify "properties".
  56         LUABIND_API int property_tag(lua_State*);
  57
  58         // this is class-specific information, poor man's vtable
  59         // this is allocated statically (removed by the compiler)
  60         // a pointer to this structure is stored in the lua tables'
  61         // metatable with the name __classrep
  62         // it is used when matching parameters to function calls
  63         // to determine possible implicit casts
  64         // it is also used when finding the best match for overloaded
  65         // methods
  66
  67     class cast_graph;
  68     class class_id_map;
  69
  70         class LUABIND_API class_rep
  71         {
  72         friend struct class_registration;
  73         friend int super_callback(lua_State*);
  74 //TODO: avoid the lua-prefix
  75         friend int lua_class_gettable(lua_State*);
  76         friend int lua_class_settable(lua_State*);
  77         friend int static_class_gettable(lua_State*);
  78         public:
  79
  80                 enum class_type
  81                 {
  82                         cpp_class = 0,
  83                         lua_class = 1
  84                 };
  85
  86                 // EXPECTS THE TOP VALUE ON THE LUA STACK TO
  87                 // BE THE USER DATA WHERE THIS CLASS IS BEING
  88                 // INSTANTIATED!
  89                 class_rep(type_id const& type
  90                         , const char* name
  91                         , lua_State* L
  92         );
  93
  94                 // used when creating a lua class
  95                 // EXPECTS THE TOP VALUE ON THE LUA STACK TO
  96                 // BE THE USER DATA WHERE THIS CLASS IS BEING
  97                 // INSTANTIATED!
  98                 class_rep(lua_State* L, const char* name);
  99
 100                 ~class_rep();
 101
 102                 std::pair<void*,void*> allocate(lua_State* L) const;
 103
 104                 // this is called as metamethod __call on the class_rep.
 105                 static int constructor_dispatcher(lua_State* L);
 106
 107                 struct base_info
 108                 {
 109                         int pointer_offset; // the offset added to the pointer to obtain a basepointer (due to multiple-inheritance)
 110                         class_rep* base;
 111                 };
 112
 113                 void add_base_class(const base_info& binfo);
 114
 115                 const std::vector<base_info>& bases() const throw() { return m_bases; }
 116
 117                 void set_type(type_id const& t) { m_type = t; }
 118                 type_id const& type() const throw() { return m_type; }
 119
 120                 const char* name() const throw() { return m_name; }
 121
 122                 // the lua reference to the metatable for this class' instances
 123                 int metatable_ref() const throw() { return m_instance_metatable; }
 124
 125                 void get_table(lua_State* L) const { m_table.push(L); }
 126                 void get_default_table(lua_State* L) const { m_default_table.push(L); }
 127
 128                 class_type get_class_type() const { return m_class_type; }
 129
 130                 void add_static_constant(const char* name, int val);
 131
 132                 static int super_callback(lua_State* L);
 133
 134                 static int lua_settable_dispatcher(lua_State* L);
 135
 136                 // called from the metamethod for __index
 137                 // obj is the object pointer
 138                 static int static_class_gettable(lua_State* L);
 139
 140                 bool has_operator_in_lua(lua_State*, int id);
 141
 142         cast_graph const& casts() const
 143         {
 144             return *m_casts;
 145         }
 146
 147         class_id_map const& classes() const
 148         {
 149             return *m_classes;
 150         }
 151
 152         private:
 153
 154                 void cache_operators(lua_State*);
 155
 156                 // this is a pointer to the type_info structure for
 157                 // this type
 158                 // warning: this may be a problem when using dll:s, since
 159                 // typeid() may actually return different pointers for the same
 160                 // type.
 161                 type_id m_type;
 162
 163                 // a list of info for every class this class derives from
 164                 // the information stored here is sufficient to do
 165                 // type casts to the base classes
 166                 std::vector<base_info> m_bases;
 167
 168                 // the class' name (as given when registered to lua with class_)
 169                 const char* m_name;
 170
 171                 // a reference to this structure itself. Since this struct
 172                 // is kept inside lua (to let lua collect it when lua_close()
 173                 // is called) we need to lock it to prevent collection.
 174                 // the actual reference is not currently used.
 175                 detail::lua_reference m_self_ref;
 176
 177                 // this should always be used when accessing
 178                 // members in instances of a class.
 179                 // this table contains c closures for all
 180                 // member functions in this class, they
 181                 // may point to both static and virtual functions
 182                 handle m_table;
 183
 184                 // this table contains default implementations of the
 185                 // virtual functions in m_table.
 186                 handle m_default_table;
 187
 188                 // the type of this class.. determines if it's written in c++ or lua
 189                 class_type m_class_type;
 190
 191                 // this is a lua reference that points to the lua table
 192                 // that is to be used as meta table for all instances
 193                 // of this class.
 194                 int m_instance_metatable;
 195
 196                 std::map<const char*, int, ltstr> m_static_constants;
 197
 198                 // the first time an operator is invoked
 199                 // we check the associated lua table
 200                 // and cache the result
 201                 int m_operator_cache;
 202
 203         cast_graph* m_casts;
 204         class_id_map* m_classes;
 205         };
 206
 207         bool is_class_rep(lua_State* L, int index);
 208
 209 }}
 210
 211 //#include <luabind/detail/overload_rep_impl.hpp>
 212
 213 #endif // LUABIND_CLASS_REP_HPP_INCLUDED