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, (void*)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     if (super_deprecation_disabled
 146         && cls->get_class_type() == class_rep::lua_class
 147         && !cls->bases().empty())
 148     {
 149         lua_pushstring(L, "super");
 150         lua_pushvalue(L, 1);
 151         lua_pushvalue(L, -3);
 152         lua_pushcclosure(L, super_callback, 2);
 153         lua_settable(L, LUA_GLOBALSINDEX);
 154     }
 155
 156     lua_pushvalue(L, -1);
 157     lua_replace(L, 1);
 158
 159     cls->get_table(L);
 160     lua_pushliteral(L, "__init");
 161     lua_gettable(L, -2);
 162
 163     lua_insert(L, 1);
 164
 165     lua_pop(L, 1);
 166     lua_insert(L, 1);
 167
 168     lua_call(L, args, 0);
 169
 170     if (super_deprecation_disabled)
 171     {
 172         lua_pushstring(L, "super");
 173         lua_pushnil(L);
 174         lua_settable(L, LUA_GLOBALSINDEX);
 175     }
 176
 177     return 1;
 178 }
 179
 180 void luabind::detail::class_rep::add_base_class(const luabind::detail::class_rep::base_info& binfo)
 181 {
 182         // If you hit this assert you are deriving from a type that is not registered
 183         // in lua. That is, in the class_<> you are giving a baseclass that isn't registered.
 184         // Please note that if you don't need to have access to the base class or the
 185         // conversion from the derived class to the base class, you don't need
 186         // to tell luabind that it derives.
 187         assert(binfo.base && "You cannot derive from an unregistered type");
 188
 189         class_rep* bcrep = binfo.base;
 190
 191         // import all static constants
 192         for (std::map<const char*, int, ltstr>::const_iterator i = bcrep->m_static_constants.begin();
 193                         i != bcrep->m_static_constants.end(); ++i)
 194         {
 195                 int& v = m_static_constants[i->first];
 196                 v = i->second;
 197         }
 198
 199         // also, save the baseclass info to be used for typecasts
 200         m_bases.push_back(binfo);
 201 }
 202
 203 LUABIND_API void luabind::disable_super_deprecation()
 204 {
 205     super_deprecation_disabled = true;
 206 }
 207
 208 int luabind::detail::class_rep::super_callback(lua_State* L)
 209 {
 210         int args = lua_gettop(L);
 211
 212         class_rep* crep = static_cast<class_rep*>(lua_touserdata(L, lua_upvalueindex(1)));
 213         class_rep* base = crep->bases()[0].base;
 214
 215         if (base->bases().empty())
 216         {
 217                 lua_pushstring(L, "super");
 218                 lua_pushnil(L);
 219                 lua_settable(L, LUA_GLOBALSINDEX);
 220         }
 221         else
 222         {
 223                 lua_pushstring(L, "super");
 224                 lua_pushlightuserdata(L, base);
 225                 lua_pushvalue(L, lua_upvalueindex(2));
 226                 lua_pushcclosure(L, super_callback, 2);
 227                 lua_settable(L, LUA_GLOBALSINDEX);
 228         }
 229
 230         base->get_table(L);
 231         lua_pushstring(L, "__init");
 232         lua_gettable(L, -2);
 233         lua_insert(L, 1);
 234         lua_pop(L, 1);
 235
 236         lua_pushvalue(L, lua_upvalueindex(2));
 237         lua_insert(L, 2);
 238
 239         lua_call(L, args + 1, 0);
 240
 241         // TODO: instead of clearing the global variable "super"
 242         // store it temporarily in the registry. maybe we should
 243         // have some kind of warning if the super global is used?
 244         lua_pushstring(L, "super");
 245         lua_pushnil(L);
 246         lua_settable(L, LUA_GLOBALSINDEX);
 247
 248         return 0;
 249 }
 250
 251
 252
 253 int luabind::detail::class_rep::lua_settable_dispatcher(lua_State* L)
 254 {
 255         class_rep* crep = static_cast<class_rep*>(lua_touserdata(L, 1));
 256
 257         // get first table
 258         crep->get_table(L);
 259
 260         // copy key, value
 261         lua_pushvalue(L, -3);
 262         lua_pushvalue(L, -3);
 263         lua_rawset(L, -3);
 264         // pop table
 265         lua_pop(L, 1);
 266
 267         // get default table
 268         crep->get_default_table(L);
 269         lua_replace(L, 1);
 270         lua_rawset(L, -3);
 271
 272         crep->m_operator_cache = 0; // invalidate cache
 273
 274         return 0;
 275 }
 276
 277 /*
 278         stack:
 279         1: class_rep
 280         2: member name
 281 */
 282 int luabind::detail::class_rep::static_class_gettable(lua_State* L)
 283 {
 284         class_rep* crep = static_cast<class_rep*>(lua_touserdata(L, 1));
 285
 286         // look in the static function table
 287         crep->get_default_table(L);
 288         lua_pushvalue(L, 2);
 289         lua_gettable(L, -2);
 290         if (!lua_isnil(L, -1)) return 1;
 291         else lua_pop(L, 2);
 292
 293         const char* key = lua_tostring(L, 2);
 294
 295         if (std::strlen(key) != lua_strlen(L, 2))
 296         {
 297                 lua_pushnil(L);
 298                 return 1;
 299         }
 300
 301         std::map<const char*, int, ltstr>::const_iterator j = crep->m_static_constants.find(key);
 302
 303         if (j != crep->m_static_constants.end())
 304         {
 305                 lua_pushnumber(L, j->second);
 306                 return 1;
 307         }
 308
 309 #ifndef LUABIND_NO_ERROR_CHECKING
 310
 311         {
 312                 std::string msg = "no static '";
 313                 msg += key;
 314                 msg += "' in class '";
 315                 msg += crep->name();
 316                 msg += "'";
 317                 lua_pushstring(L, msg.c_str());
 318         }
 319         lua_error(L);
 320
 321 #endif
 322
 323         lua_pushnil(L);
 324
 325         return 1;
 326 }
 327
 328 bool luabind::detail::is_class_rep(lua_State* L, int index)
 329 {
 330         if (lua_getmetatable(L, index) == 0) return false;
 331
 332         lua_pushstring(L, "__luabind_classrep");
 333         lua_gettable(L, -2);
 334         if (lua_toboolean(L, -1))
 335         {
 336                 lua_pop(L, 2);
 337                 return true;
 338         }
 339
 340         lua_pop(L, 2);
 341         return false;
 342 }
 343
 344 void luabind::detail::finalize(lua_State* L, class_rep* crep)
 345 {
 346         if (crep->get_class_type() != class_rep::lua_class) return;
 347
 348 //      lua_pushvalue(L, -1); // copy the object ref
 349         crep->get_table(L);
 350     lua_pushliteral(L, "__finalize");
 351         lua_gettable(L, -2);
 352         lua_remove(L, -2);
 353
 354         if (lua_isnil(L, -1))
 355         {
 356                 lua_pop(L, 1);
 357         }
 358         else
 359         {
 360                 lua_pushvalue(L, -2);
 361                 lua_call(L, 1, 0);
 362         }
 363
 364         for (std::vector<class_rep::base_info>::const_iterator
 365                         i = crep->bases().begin(); i != crep->bases().end(); ++i)
 366         {
 367                 if (i->base) finalize(L, i->base);
 368         }
 369 }
 370
 371 void luabind::detail::class_rep::cache_operators(lua_State* L)
 372 {
 373         m_operator_cache = 0x1;
 374
 375         for (int i = 0; i < number_of_operators; ++i)
 376         {
 377                 get_table(L);
 378                 lua_pushstring(L, get_operator_name(i));
 379                 lua_rawget(L, -2);
 380
 381                 if (lua_isfunction(L, -1)) m_operator_cache |= 1 << (i + 1);
 382
 383                 lua_pop(L, 2);
 384         }
 385 }
 386
 387 bool luabind::detail::class_rep::has_operator_in_lua(lua_State* L, int id)
 388 {
 389         if ((m_operator_cache & 0x1) == 0)
 390                 cache_operators(L);
 391
 392         const int mask = 1 << (id + 1);
 393
 394         return (m_operator_cache & mask) != 0;
 395 }