src/class_registry.cpp

   1 // Copyright (c) 2004 Daniel Wallin
   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 #define LUABIND_BUILDING
  24
  25 #include <luabind/lua_include.hpp>
  26
  27 #include <luabind/luabind.hpp>
  28 #include <luabind/detail/class_registry.hpp>
  29 #include <luabind/detail/class_rep.hpp>
  30 #include <luabind/detail/operator_id.hpp>
  31
  32 namespace luabind { namespace detail {
  33
  34     namespace {
  35
  36         void add_operator_to_metatable(lua_State* L, int op_index)
  37         {
  38             lua_pushstring(L, get_operator_name(op_index));
  39             lua_pushstring(L, get_operator_name(op_index));
  40             lua_pushboolean(L, op_index == op_unm || op_index == op_len);
  41             lua_pushcclosure(L, &class_rep::operator_dispatcher, 2);
  42             lua_settable(L, -3);
  43         }
  44
  45         int create_cpp_class_metatable(lua_State* L)
  46         {
  47             lua_newtable(L);
  48
  49             // mark the table with our (hopefully) unique tag
  50             // that says that the user data that has this
  51             // metatable is a class_rep
  52             lua_pushstring(L, "__luabind_classrep");
  53             lua_pushboolean(L, 1);
  54             lua_rawset(L, -3);
  55
  56             lua_pushstring(L, "__gc");
  57             lua_pushcclosure(
  58                 L
  59               , &garbage_collector_s<
  60                     detail::class_rep
  61                 >::apply
  62                 , 0);
  63
  64             lua_rawset(L, -3);
  65
  66             lua_pushstring(L, "__call");
  67             lua_pushcclosure(L, &class_rep::constructor_dispatcher, 0);
  68             lua_rawset(L, -3);
  69
  70             lua_pushstring(L, "__index");
  71             lua_pushcclosure(L, &class_rep::static_class_gettable, 0);
  72             lua_rawset(L, -3);
  73
  74             lua_pushstring(L, "__newindex");
  75             lua_pushcclosure(L, &class_rep::lua_settable_dispatcher, 0);
  76             lua_rawset(L, -3);
  77
  78             return luaL_ref(L, LUA_REGISTRYINDEX);
  79         }
  80
  81         int create_cpp_instance_metatable(lua_State* L)
  82         {
  83             lua_newtable(L);
  84
  85             // just indicate that this really is a class and not just
  86             // any user data
  87             lua_pushstring(L, "__luabind_class");
  88             lua_pushboolean(L, 1);
  89             lua_rawset(L, -3);
  90
  91             // __index and __newindex will simply be references to the
  92             // class_rep which in turn has it's own metamethods for __index
  93             // and __newindex
  94             lua_pushstring(L, "__index");
  95             lua_pushcclosure(L, &class_rep::gettable_dispatcher, 0);
  96             lua_rawset(L, -3);
  97
  98             lua_pushstring(L, "__newindex");
  99             lua_pushcclosure(L, &class_rep::settable_dispatcher, 0);
 100             lua_rawset(L, -3);
 101
 102             lua_pushstring(L, "__gc");
 103
 104             lua_pushcclosure(L, detail::object_rep::garbage_collector, 0);
 105             lua_rawset(L, -3);
 106
 107             lua_pushstring(L, "__gettable");
 108             lua_pushcclosure(L, &class_rep::static_class_gettable, 0);
 109             lua_rawset(L, -3);
 110
 111             for (int i = 0; i < number_of_operators; ++i)
 112                 add_operator_to_metatable(L, i);
 113
 114             // store a reference to the instance-metatable in our class_rep
 115             assert((lua_type(L, -1) == LUA_TTABLE)
 116                 && "internal error, please report");
 117
 118             return luaL_ref(L, LUA_REGISTRYINDEX);
 119         }
 120
 121         int create_lua_class_metatable(lua_State* L)
 122         {
 123             lua_newtable(L);
 124
 125             lua_pushstring(L, "__luabind_classrep");
 126             lua_pushboolean(L, 1);
 127             lua_rawset(L, -3);
 128
 129             lua_pushstring(L, "__gc");
 130             lua_pushcclosure(
 131                 L
 132               , &detail::garbage_collector_s<
 133                     detail::class_rep
 134                 >::apply
 135                 , 0);
 136
 137             lua_rawset(L, -3);
 138
 139             lua_pushstring(L, "__newindex");
 140             lua_pushcclosure(L, &class_rep::lua_settable_dispatcher, 0);
 141             lua_rawset(L, -3);
 142
 143             lua_pushstring(L, "__call");
 144             lua_pushcclosure(L, &class_rep::constructor_dispatcher, 0);
 145             lua_rawset(L, -3);
 146
 147             lua_pushstring(L, "__index");
 148             lua_pushcclosure(L, &class_rep::static_class_gettable, 0);
 149             lua_rawset(L, -3);
 150
 151             return luaL_ref(L, LUA_REGISTRYINDEX);
 152         }
 153
 154         int create_lua_instance_metatable(lua_State* L)
 155         {
 156             lua_newtable(L);
 157
 158             // just indicate that this really is a class and not just
 159             // any user data
 160             lua_pushstring(L, "__luabind_class");
 161             lua_pushboolean(L, 1);
 162             lua_rawset(L, -3);
 163
 164             lua_pushstring(L, "__index");
 165             lua_pushcclosure(L, &class_rep::gettable_dispatcher, 0);
 166             lua_rawset(L, -3);
 167
 168             lua_pushstring(L, "__newindex");
 169             lua_pushcclosure(L, &class_rep::settable_dispatcher, 0);
 170             lua_rawset(L, -3);
 171
 172             lua_pushstring(L, "__gc");
 173             lua_pushcclosure(L, detail::object_rep::garbage_collector, 0);
 174             lua_rawset(L, -3);
 175
 176             for (int i = 0; i < number_of_operators; ++i)
 177                 add_operator_to_metatable(L, i);
 178
 179             // store a reference to the instance-metatable in our class_rep
 180             return luaL_ref(L, LUA_REGISTRYINDEX);
 181         }
 182
 183     } // namespace unnamed
 184
 185     class class_rep;
 186
 187     class_registry::class_registry(lua_State* L)
 188         : m_cpp_instance_metatable(create_cpp_instance_metatable(L))
 189         , m_cpp_class_metatable(create_cpp_class_metatable(L))
 190         , m_lua_instance_metatable(create_lua_instance_metatable(L))
 191         , m_lua_class_metatable(create_lua_class_metatable(L))
 192     {
 193     }
 194
 195     class_registry* class_registry::get_registry(lua_State* L)
 196     {
 197
 198 #ifdef LUABIND_NOT_THREADSAFE
 199
 200         // if we don't have to be thread safe, we can keep a
 201         // chache of the class_registry pointer without the
 202         // need of a mutex
 203         static lua_State* cache_key = 0;
 204         static class_registry* registry_cache = 0;
 205         if (cache_key == L) return registry_cache;
 206
 207 #endif
 208
 209         lua_pushstring(L, "__luabind_classes");
 210         lua_gettable(L, LUA_REGISTRYINDEX);
 211         class_registry* p = static_cast<class_registry*>(lua_touserdata(L, -1));
 212         lua_pop(L, 1);
 213
 214 #ifdef LUABIND_NOT_THREADSAFE
 215
 216         cache_key = L;
 217         registry_cache = p;
 218
 219 #endif
 220
 221         return p;
 222     }
 223
 224     void class_registry::add_class(LUABIND_TYPE_INFO info, class_rep* crep)
 225     {
 226         // class is already registered
 227         assert((m_classes.find(info) == m_classes.end())
 228             && "you are trying to register a class twice");
 229         m_classes[info] = crep;
 230     }
 231
 232     class_rep* class_registry::find_class(LUABIND_TYPE_INFO info) const
 233     {
 234         std::map<LUABIND_TYPE_INFO, class_rep*, cmp>::const_iterator i(
 235             m_classes.find(info));
 236
 237         if (i == m_classes.end()) return 0; // the type is not registered
 238         return i->second;
 239     }
 240
 241 }} // namespace luabind::detail
 242