src/class_rep.cpp

   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 #define LUABIND_BUILDING
  24
  25 #include <luabind/lua_include.hpp>
  26
  27 #include <luabind/detail/stack_utils.hpp>
  28 #include <luabind/detail/conversion_storage.hpp>
  29 #include <luabind/luabind.hpp>
  30 #include <luabind/exception_handler.hpp>
  31 #include <luabind/get_main_thread.hpp>
  32 #include <utility>
  33
  34 using namespace luabind::detail;
  35
  36 namespace luabind { namespace detail
  37 {
  38         LUABIND_API int property_tag(lua_State* L)
  39         {
  40                 lua_pushstring(L, "luabind: property_tag function can't be called");
  41                 lua_error(L);
  42                 return 0;
  43         }
  44 }}
  45
  46 luabind::detail::class_rep::class_rep(type_id const& type
  47         , const char* name
  48         , lua_State* L
  49 )
  50         : m_type(type)
  51         , m_name(name)
  52         , m_class_type(cpp_class)
  53         , m_operator_cache(0)
  54 {
  55         lua_newtable(L);
  56         handle(L, -1).swap(m_table);
  57         lua_newtable(L);
  58         handle(L, -1).swap(m_default_table);
  59         lua_pop(L, 2);
  60
  61         class_registry* r = class_registry::get_registry(L);
  62         assert((r->cpp_class() != LUA_NOREF) && "you must call luabind::open()");
  63
  64         lua_rawgeti(L, LUA_REGISTRYINDEX, r->cpp_class());
  65         lua_setmetatable(L, -2);
  66
  67         lua_pushvalue(L, -1); // duplicate our user data
  68         m_self_ref.set(L);
  69
  70         m_instance_metatable = r->cpp_instance();
  71
  72     lua_pushstring(L, "__luabind_cast_graph");
  73     lua_gettable(L, LUA_REGISTRYINDEX);
  74     m_casts = static_cast<cast_graph*>(lua_touserdata(L, -1));
  75     lua_pop(L, 1);
  76
  77     lua_pushstring(L, "__luabind_class_id_map");
  78     lua_gettable(L, LUA_REGISTRYINDEX);
  79     m_classes = static_cast<class_id_map*>(lua_touserdata(L, -1));
  80     lua_pop(L, 1);
  81 }
  82
  83 luabind::detail::class_rep::class_rep(lua_State* L, const char* name)
  84         : m_type(typeid(null_type))
  85         , m_name(name)
  86         , m_class_type(lua_class)
  87         , m_operator_cache(0)
  88 {
  89         lua_newtable(L);
  90         handle(L, -1).swap(m_table);
  91         lua_newtable(L);
  92         handle(L, -1).swap(m_default_table);
  93         lua_pop(L, 2);
  94
  95         class_registry* r = class_registry::get_registry(L);
  96         assert((r->cpp_class() != LUA_NOREF) && "you must call luabind::open()");
  97
  98         lua_rawgeti(L, LUA_REGISTRYINDEX, r->lua_class());
  99         lua_setmetatable(L, -2);
 100         lua_pushvalue(L, -1); // duplicate our user data
 101         m_self_ref.set(L);
 102
 103         m_instance_metatable = r->lua_instance();
 104
 105     lua_pushstring(L, "__luabind_cast_graph");
 106     lua_gettable(L, LUA_REGISTRYINDEX);
 107     m_casts = static_cast<cast_graph*>(lua_touserdata(L, -1));
 108     lua_pop(L, 1);
 109
 110     lua_pushstring(L, "__luabind_class_id_map");
 111     lua_gettable(L, LUA_REGISTRYINDEX);
 112     m_classes = static_cast<class_id_map*>(lua_touserdata(L, -1));
 113     lua_pop(L, 1);
 114 }
 115
 116 luabind::detail::class_rep::~class_rep()
 117 {
 118 }
 119
 120 // leaves object on lua stack
 121 std::pair<void*,void*>
 122 luabind::detail::class_rep::allocate(lua_State* L) const
 123 {
 124         const int size = sizeof(object_rep);
 125         char* mem = static_cast<char*>(lua_newuserdata(L, size));
 126         return std::pair<void*,void*>(mem, 0);
 127 }
 128
 129 namespace
 130 {
 131
 132   bool super_deprecation_disabled = false;
 133
 134 } // namespace unnamed
 135
 136 // this is called as metamethod __call on the class_rep.
 137 int luabind::detail::class_rep::constructor_dispatcher(lua_State* L)
 138 {
 139     class_rep* cls = static_cast<class_rep*>(lua_touserdata(L, 1));
 140
 141     int args = lua_gettop(L);
 142
 143     push_new_instance(L, cls);
 144
 145     cls->get_table(L);
 146     lua_setfenv(L, -2);
 147
 148     lua_rawgeti(L, LUA_REGISTRYINDEX, cls->metatable_ref());
 149     lua_setmetatable(L, -2);
 150
 151     if (super_deprecation_disabled
 152         && cls->get_class_type() == class_rep::lua_class
 153         && !cls->bases().empty())
 154     {
 155         lua_pushstring(L, "super");
 156         lua_pushvalue(L, 1);
 157         lua_pushvalue(L, -3);
 158         lua_pushcclosure(L, super_callback, 2);
 159         lua_settable(L, LUA_GLOBALSINDEX);
 160     }
 161
 162     lua_pushvalue(L, -1);
 163     lua_replace(L, 1);
 164
 165     cls->get_table(L);
 166     lua_pushliteral(L, "__init");
 167     lua_gettable(L, -2);
 168
 169     lua_insert(L, 1);
 170
 171     lua_pop(L, 1);
 172     lua_insert(L, 1);
 173
 174     lua_call(L, args, 0);
 175
 176     if (super_deprecation_disabled)
 177     {
 178         lua_pushstring(L, "super");
 179         lua_pushnil(L);
 180         lua_settable(L, LUA_GLOBALSINDEX);
 181     }
 182
 183     return 1;
 184 }
 185
 186 void luabind::detail::class_rep::add_base_class(const luabind::detail::class_rep::base_info& binfo)
 187 {
 188         // If you hit this assert you are deriving from a type that is not registered
 189         // in lua. That is, in the class_<> you are giving a baseclass that isn't registered.
 190         // Please note that if you don't need to have access to the base class or the
 191         // conversion from the derived class to the base class, you don't need
 192         // to tell luabind that it derives.
 193         assert(binfo.base && "You cannot derive from an unregistered type");
 194
 195         class_rep* bcrep = binfo.base;
 196
 197         // import all static constants
 198         for (std::map<const char*, int, ltstr>::const_iterator i = bcrep->m_static_constants.begin();
 199                         i != bcrep->m_static_constants.end(); ++i)
 200         {
 201                 int& v = m_static_constants[i->first];
 202                 v = i->second;
 203         }
 204
 205         // also, save the baseclass info to be used for typecasts
 206         m_bases.push_back(binfo);
 207 }
 208
 209 LUABIND_API void luabind::disable_super_deprecation()
 210 {
 211     super_deprecation_disabled = true;
 212 }
 213
 214 int luabind::detail::class_rep::super_callback(lua_State* L)
 215 {
 216         int args = lua_gettop(L);
 217
 218         class_rep* crep = static_cast<class_rep*>(lua_touserdata(L, lua_upvalueindex(1)));
 219         class_rep* base = crep->bases()[0].base;
 220
 221         if (base->bases().empty())
 222         {
 223                 lua_pushstring(L, "super");
 224                 lua_pushnil(L);
 225                 lua_settable(L, LUA_GLOBALSINDEX);
 226         }
 227         else
 228         {
 229                 lua_pushstring(L, "super");
 230                 lua_pushlightuserdata(L, base);
 231                 lua_pushvalue(L, lua_upvalueindex(2));
 232                 lua_pushcclosure(L, super_callback, 2);
 233                 lua_settable(L, LUA_GLOBALSINDEX);
 234         }
 235
 236         base->get_table(L);
 237         lua_pushstring(L, "__init");
 238         lua_gettable(L, -2);
 239         lua_insert(L, 1);
 240         lua_pop(L, 1);
 241
 242         lua_pushvalue(L, lua_upvalueindex(2));
 243         lua_insert(L, 2);
 244
 245         lua_call(L, args + 1, 0);
 246
 247         // TODO: instead of clearing the global variable "super"
 248         // store it temporarily in the registry. maybe we should
 249         // have some kind of warning if the super global is used?
 250         lua_pushstring(L, "super");
 251         lua_pushnil(L);
 252         lua_settable(L, LUA_GLOBALSINDEX);
 253
 254         return 0;
 255 }
 256
 257
 258
 259 int luabind::detail::class_rep::lua_settable_dispatcher(lua_State* L)
 260 {
 261         class_rep* crep = static_cast<class_rep*>(lua_touserdata(L, 1));
 262
 263         // get first table
 264         crep->get_table(L);
 265
 266         // copy key, value
 267         lua_pushvalue(L, -3);
 268         lua_pushvalue(L, -3);
 269         lua_rawset(L, -3);
 270         // pop table
 271         lua_pop(L, 1);
 272
 273         // get default table
 274         crep->get_default_table(L);
 275         lua_replace(L, 1);
 276         lua_rawset(L, -3);
 277
 278         crep->m_operator_cache = 0; // invalidate cache
 279
 280         return 0;
 281 }
 282
 283 /*
 284         stack:
 285         1: class_rep
 286         2: member name
 287 */
 288 int luabind::detail::class_rep::static_class_gettable(lua_State* L)
 289 {
 290         class_rep* crep = static_cast<class_rep*>(lua_touserdata(L, 1));
 291
 292         // look in the static function table
 293         crep->get_default_table(L);
 294         lua_pushvalue(L, 2);
 295         lua_gettable(L, -2);
 296         if (!lua_isnil(L, -1)) return 1;
 297         else lua_pop(L, 2);
 298
 299         const char* key = lua_tostring(L, 2);
 300
 301         if (std::strlen(key) != lua_strlen(L, 2))
 302         {
 303                 lua_pushnil(L);
 304                 return 1;
 305         }
 306
 307         std::map<const char*, int, ltstr>::const_iterator j = crep->m_static_constants.find(key);
 308
 309         if (j != crep->m_static_constants.end())
 310         {
 311                 lua_pushnumber(L, j->second);
 312                 return 1;
 313         }
 314
 315 #ifndef LUABIND_NO_ERROR_CHECKING
 316
 317         {
 318                 std::string msg = "no static '";
 319                 msg += key;
 320                 msg += "' in class '";
 321                 msg += crep->name();
 322                 msg += "'";
 323                 lua_pushstring(L, msg.c_str());
 324         }
 325         lua_error(L);
 326
 327 #endif
 328
 329         lua_pushnil(L);
 330
 331         return 1;
 332 }
 333
 334 bool luabind::detail::is_class_rep(lua_State* L, int index)
 335 {
 336         if (lua_getmetatable(L, index) == 0) return false;
 337
 338         lua_pushstring(L, "__luabind_classrep");
 339         lua_gettable(L, -2);
 340         if (lua_toboolean(L, -1))
 341         {
 342                 lua_pop(L, 2);
 343                 return true;
 344         }
 345
 346         lua_pop(L, 2);
 347         return false;
 348 }
 349
 350 void luabind::detail::finalize(lua_State* L, class_rep* crep)
 351 {
 352         if (crep->get_class_type() != class_rep::lua_class) return;
 353
 354 //      lua_pushvalue(L, -1); // copy the object ref
 355         crep->get_table(L);
 356     lua_pushliteral(L, "__finalize");
 357         lua_gettable(L, -2);
 358         lua_remove(L, -2);
 359
 360         if (lua_isnil(L, -1))
 361         {
 362                 lua_pop(L, 1);
 363         }
 364         else
 365         {
 366                 lua_pushvalue(L, -2);
 367                 lua_call(L, 1, 0);
 368         }
 369
 370         for (std::vector<class_rep::base_info>::const_iterator
 371                         i = crep->bases().begin(); i != crep->bases().end(); ++i)
 372         {
 373                 if (i->base) finalize(L, i->base);
 374         }
 375 }
 376
 377 void luabind::detail::class_rep::cache_operators(lua_State* L)
 378 {
 379         m_operator_cache = 0x1;
 380
 381         for (int i = 0; i < number_of_operators; ++i)
 382         {
 383                 get_table(L);
 384                 lua_pushstring(L, get_operator_name(i));
 385                 lua_rawget(L, -2);
 386
 387                 if (lua_isfunction(L, -1)) m_operator_cache |= 1 << (i + 1);
 388
 389                 lua_pop(L, 2);
 390         }
 391 }
 392
 393 bool luabind::detail::class_rep::has_operator_in_lua(lua_State* L, int id)
 394 {
 395         if ((m_operator_cache & 0x1) == 0)
 396                 cache_operators(L);
 397
 398         const int mask = 1 << (id + 1);
 399
 400         return (m_operator_cache & mask) != 0;
 401 }