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/detail/object_rep.hpp>
  36 #include <luabind/detail/garbage_collector.hpp>
  37 #include <luabind/detail/operator_id.hpp>
  38 #include <luabind/detail/class_registry.hpp>
  39 #include <luabind/error.hpp>
  40 #include <luabind/handle.hpp>
  41 #include <luabind/detail/primitives.hpp>
  42 #include <luabind/typeid.hpp>
  43 #include <luabind/detail/ref.hpp>
  44
  45 namespace luabind { namespace detail
  46 {
  47
  48         LUABIND_API std::string stack_content_by_name(lua_State* L, int start_index);
  49
  50         struct class_registration;
  51
  52         struct conversion_storage;
  53
  54         // This function is used as a tag to identify "properties".
  55         LUABIND_API int property_tag(lua_State*);
  56
  57         // this is class-specific information, poor man's vtable
  58         // this is allocated statically (removed by the compiler)
  59         // a pointer to this structure is stored in the lua tables'
  60         // metatable with the name __classrep
  61         // it is used when matching parameters to function calls
  62         // to determine possible implicit casts
  63         // it is also used when finding the best match for overloaded
  64         // methods
  65
  66         class LUABIND_API class_rep
  67         {
  68         friend struct class_registration;
  69         friend int super_callback(lua_State*);
  70 //TODO: avoid the lua-prefix
  71         friend int lua_class_gettable(lua_State*);
  72         friend int lua_class_settable(lua_State*);
  73         friend int static_class_gettable(lua_State*);
  74         public:
  75
  76                 enum class_type
  77                 {
  78                         cpp_class = 0,
  79                         lua_class = 1
  80                 };
  81
  82                 // EXPECTS THE TOP VALUE ON THE LUA STACK TO
  83                 // BE THE USER DATA WHERE THIS CLASS IS BEING
  84                 // INSTANTIATED!
  85                 class_rep(type_id const& type
  86                         , const char* name
  87                         , lua_State* L
  88         );
  89
  90                 // used when creating a lua class
  91                 // EXPECTS THE TOP VALUE ON THE LUA STACK TO
  92                 // BE THE USER DATA WHERE THIS CLASS IS BEING
  93                 // INSTANTIATED!
  94                 class_rep(lua_State* L, const char* name);
  95
  96                 ~class_rep();
  97
  98                 std::pair<void*,void*> allocate(lua_State* L) const;
  99
 100                 // this is called as metamethod __call on the class_rep.
 101                 static int constructor_dispatcher(lua_State* L);
 102
 103                 struct base_info
 104                 {
 105                         int pointer_offset; // the offset added to the pointer to obtain a basepointer (due to multiple-inheritance)
 106                         class_rep* base;
 107                 };
 108
 109                 void add_base_class(const base_info& binfo);
 110
 111                 const std::vector<base_info>& bases() const throw() { return m_bases; }
 112
 113                 void set_type(type_id const& t) { m_type = t; }
 114                 type_id const& type() const throw() { return m_type; }
 115
 116                 const char* name() const throw() { return m_name; }
 117
 118                 // the lua reference to the metatable for this class' instances
 119                 int metatable_ref() const throw() { return m_instance_metatable; }
 120
 121                 void get_table(lua_State* L) const { m_table.push(L); }
 122                 void get_default_table(lua_State* L) const { m_default_table.push(L); }
 123
 124                 class_type get_class_type() const { return m_class_type; }
 125
 126                 void add_static_constant(const char* name, int val);
 127
 128                 static int super_callback(lua_State* L);
 129
 130                 static int lua_settable_dispatcher(lua_State* L);
 131
 132                 // called from the metamethod for __index
 133                 // obj is the object pointer
 134                 static int static_class_gettable(lua_State* L);
 135
 136                 bool has_operator_in_lua(lua_State*, int id);
 137
 138         private:
 139
 140                 void cache_operators(lua_State*);
 141
 142                 // this is a pointer to the type_info structure for
 143                 // this type
 144                 // warning: this may be a problem when using dll:s, since
 145                 // typeid() may actually return different pointers for the same
 146                 // type.
 147                 type_id m_type;
 148
 149                 // a list of info for every class this class derives from
 150                 // the information stored here is sufficient to do
 151                 // type casts to the base classes
 152                 std::vector<base_info> m_bases;
 153
 154                 // the class' name (as given when registered to lua with class_)
 155                 const char* m_name;
 156
 157                 // a reference to this structure itself. Since this struct
 158                 // is kept inside lua (to let lua collect it when lua_close()
 159                 // is called) we need to lock it to prevent collection.
 160                 // the actual reference is not currently used.
 161                 detail::lua_reference m_self_ref;
 162
 163                 // this should always be used when accessing
 164                 // members in instances of a class.
 165                 // this table contains c closures for all
 166                 // member functions in this class, they
 167                 // may point to both static and virtual functions
 168                 handle m_table;
 169
 170                 // this table contains default implementations of the
 171                 // virtual functions in m_table.
 172                 handle m_default_table;
 173
 174                 // the type of this class.. determines if it's written in c++ or lua
 175                 class_type m_class_type;
 176
 177                 // this is a lua reference that points to the lua table
 178                 // that is to be used as meta table for all instances
 179                 // of this class.
 180                 int m_instance_metatable;
 181
 182                 std::map<const char*, int, ltstr> m_static_constants;
 183
 184                 // the first time an operator is invoked
 185                 // we check the associated lua table
 186                 // and cache the result
 187                 int m_operator_cache;
 188         };
 189
 190         bool is_class_rep(lua_State* L, int index);
 191
 192 }}
 193
 194 //#include <luabind/detail/overload_rep_impl.hpp>
 195
 196 #endif // LUABIND_CLASS_REP_HPP_INCLUDED