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 <utility>
  32
  33 using namespace luabind::detail;
  34
  35 namespace luabind { namespace detail
  36 {
  37         LUABIND_API int property_tag(lua_State* L)
  38         {
  39                 lua_pushstring(L, "luabind: property_tag function can't be called");
  40                 lua_error(L);
  41                 return 0;
  42         }
  43 }}
  44
  45 luabind::detail::class_rep::class_rep(type_id const& type
  46         , const char* name
  47         , lua_State* L
  48 )
  49         : m_type(type)
  50         , m_name(name)
  51         , m_class_type(cpp_class)
  52         , m_operator_cache(0)
  53 {
  54         lua_newtable(L);
  55         handle(L, -1).swap(m_table);
  56         lua_newtable(L);
  57         handle(L, -1).swap(m_default_table);
  58         lua_pop(L, 2);
  59
  60         class_registry* r = class_registry::get_registry(L);
  61         assert((r->cpp_class() != LUA_NOREF) && "you must call luabind::open()");
  62
  63         lua_rawgeti(L, LUA_REGISTRYINDEX, r->cpp_class());
  64         lua_setmetatable(L, -2);
  65
  66         lua_pushvalue(L, -1); // duplicate our user data
  67         m_self_ref.set(L);
  68
  69         m_instance_metatable = r->cpp_instance();
  70
  71     lua_pushstring(L, "__luabind_cast_graph");
  72     lua_gettable(L, LUA_REGISTRYINDEX);
  73     m_casts = static_cast<cast_graph*>(lua_touserdata(L, -1));
  74     lua_pop(L, 1);
  75
  76     lua_pushstring(L, "__luabind_class_id_map");
  77     lua_gettable(L, LUA_REGISTRYINDEX);
  78     m_classes = static_cast<class_id_map*>(lua_touserdata(L, -1));
  79     lua_pop(L, 1);
  80 }
  81
  82 luabind::detail::class_rep::class_rep(lua_State* L, const char* name)
  83         : m_type(typeid(null_type))
  84         , m_name(name)
  85         , m_class_type(lua_class)
  86         , m_operator_cache(0)
  87 {
  88         lua_newtable(L);
  89         handle(L, -1).swap(m_table);
  90         lua_newtable(L);
  91         handle(L, -1).swap(m_default_table);
  92         lua_pop(L, 2);
  93
  94         class_registry* r = class_registry::get_registry(L);
  95         assert((r->cpp_class() != LUA_NOREF) && "you must call luabind::open()");
  96
  97         lua_rawgeti(L, LUA_REGISTRYINDEX, r->lua_class());
  98         lua_setmetatable(L, -2);
  99         lua_pushvalue(L, -1); // duplicate our user data
 100         m_self_ref.set(L);
 101
 102         m_instance_metatable = r->lua_instance();
 103
 104     lua_pushstring(L, "__luabind_cast_graph");
 105     lua_gettable(L, LUA_REGISTRYINDEX);
 106     m_casts = static_cast<cast_graph*>(lua_touserdata(L, -1));
 107     lua_pop(L, 1);
 108
 109     lua_pushstring(L, "__luabind_class_id_map");
 110     lua_gettable(L, LUA_REGISTRYINDEX);
 111     m_classes = static_cast<class_id_map*>(lua_touserdata(L, -1));
 112     lua_pop(L, 1);
 113 }
 114
 115 luabind::detail::class_rep::~class_rep()
 116 {
 117 }
 118
 119 // leaves object on lua stack
 120 std::pair<void*,void*>
 121 luabind::detail::class_rep::allocate(lua_State* L) const
 122 {
 123         const int size = sizeof(object_rep);
 124         char* mem = static_cast<char*>(lua_newuserdata(L, size));
 125         return std::pair<void*,void*>(mem, 0);
 126 }
 127
 128
 129 // this is called as metamethod __call on the class_rep.
 130 int luabind::detail::class_rep::constructor_dispatcher(lua_State* L)
 131 {
 132     class_rep* cls = static_cast<class_rep*>(lua_touserdata(L, 1));
 133
 134     int args = lua_gettop(L);
 135
 136     push_new_instance(L, cls);
 137
 138     cls->get_table(L);
 139     lua_setfenv(L, -2);
 140
 141     lua_rawgeti(L, LUA_REGISTRYINDEX, cls->metatable_ref());
 142     lua_setmetatable(L, -2);
 143
 144     if (cls->get_class_type() == class_rep::lua_class
 145      && !cls->bases().empty())
 146     {
 147         lua_pushstring(L, "super");
 148         lua_pushvalue(L, 1);
 149         lua_pushvalue(L, -3);
 150         lua_pushcclosure(L, super_callback, 2);
 151         lua_settable(L, LUA_GLOBALSINDEX);
 152     }
 153
 154     lua_pushvalue(L, -1);
 155     lua_replace(L, 1);
 156
 157     cls->get_table(L);
 158     lua_pushstring(L, "__init");
 159     lua_gettable(L, -2);
 160
 161     lua_insert(L, 1);
 162
 163     lua_pop(L, 1);
 164     lua_insert(L, 1);
 165
 166     lua_call(L, args, 0);
 167
 168     return 1;
 169 }
 170
 171 void luabind::detail::class_rep::add_base_class(const luabind::detail::class_rep::base_info& binfo)
 172 {
 173         // If you hit this assert you are deriving from a type that is not registered
 174         // in lua. That is, in the class_<> you are giving a baseclass that isn't registered.
 175         // Please note that if you don't need to have access to the base class or the
 176         // conversion from the derived class to the base class, you don't need
 177         // to tell luabind that it derives.
 178         assert(binfo.base && "You cannot derive from an unregistered type");
 179
 180         class_rep* bcrep = binfo.base;
 181
 182         // import all static constants
 183         for (std::map<const char*, int, ltstr>::const_iterator i = bcrep->m_static_constants.begin();
 184                         i != bcrep->m_static_constants.end(); ++i)
 185         {
 186                 int& v = m_static_constants[i->first];
 187                 v = i->second;
 188         }
 189
 190         // also, save the baseclass info to be used for typecasts
 191         m_bases.push_back(binfo);
 192 }
 193
 194 namespace
 195 {
 196
 197   bool super_deprecation_disabled = false;
 198
 199 } // namespace unnamed
 200
 201 LUABIND_API void luabind::disable_super_deprecation()
 202 {
 203     super_deprecation_disabled = true;
 204 }
 205
 206 int luabind::detail::class_rep::super_callback(lua_State* L)
 207 {
 208         if (!super_deprecation_disabled)
 209         {
 210                 lua_pushstring(L,
 211                         "DEPRECATION: 'super' has been deprecated in favor of "
 212                         "directly calling the base class __init() function. "
 213                         "This error can be disabled by calling 'luabind::disable_super_deprecation()'."
 214                 );
 215                 lua_error(L);
 216         }
 217
 218         int args = lua_gettop(L);
 219
 220         class_rep* crep = static_cast<class_rep*>(lua_touserdata(L, lua_upvalueindex(1)));
 221         class_rep* base = crep->bases()[0].base;
 222
 223         if (base->bases().empty())
 224         {
 225                 lua_pushstring(L, "super");
 226                 lua_pushnil(L);
 227                 lua_settable(L, LUA_GLOBALSINDEX);
 228         }
 229         else
 230         {
 231                 lua_pushstring(L, "super");
 232                 lua_pushlightuserdata(L, base);
 233                 lua_pushvalue(L, lua_upvalueindex(2));
 234                 lua_pushcclosure(L, super_callback, 2);
 235                 lua_settable(L, LUA_GLOBALSINDEX);
 236         }
 237
 238         base->get_table(L);
 239         lua_pushstring(L, "__init");
 240         lua_gettable(L, -2);
 241         lua_insert(L, 1);
 242         lua_pop(L, 1);
 243
 244         lua_pushvalue(L, lua_upvalueindex(2));
 245         lua_insert(L, 2);
 246
 247         lua_call(L, args + 1, 0);
 248
 249         // TODO: instead of clearing the global variable "super"
 250         // store it temporarily in the registry. maybe we should
 251         // have some kind of warning if the super global is used?
 252         lua_pushstring(L, "super");
 253         lua_pushnil(L);
 254         lua_settable(L, LUA_GLOBALSINDEX);
 255
 256         return 0;
 257 }
 258
 259
 260
 261 int luabind::detail::class_rep::lua_settable_dispatcher(lua_State* L)
 262 {
 263         class_rep* crep = static_cast<class_rep*>(lua_touserdata(L, 1));
 264
 265         // get first table
 266         crep->get_table(L);
 267
 268         // copy key, value
 269         lua_pushvalue(L, -3);
 270         lua_pushvalue(L, -3);
 271         lua_rawset(L, -3);
 272         // pop table
 273         lua_pop(L, 1);
 274
 275         // get default table
 276         crep->get_default_table(L);
 277         lua_replace(L, 1);
 278         lua_rawset(L, -3);
 279
 280         crep->m_operator_cache = 0; // invalidate cache
 281
 282         return 0;
 283 }
 284
 285 /*
 286         stack:
 287         1: class_rep
 288         2: member name
 289 */
 290 int luabind::detail::class_rep::static_class_gettable(lua_State* L)
 291 {
 292         class_rep* crep = static_cast<class_rep*>(lua_touserdata(L, 1));
 293
 294         // look in the static function table
 295         crep->get_default_table(L);
 296         lua_pushvalue(L, 2);
 297         lua_gettable(L, -2);
 298         if (!lua_isnil(L, -1)) return 1;
 299         else lua_pop(L, 2);
 300
 301         const char* key = lua_tostring(L, 2);
 302
 303         if (std::strlen(key) != lua_strlen(L, 2))
 304         {
 305                 lua_pushnil(L);
 306                 return 1;
 307         }
 308
 309         std::map<const char*, int, ltstr>::const_iterator j = crep->m_static_constants.find(key);
 310
 311         if (j != crep->m_static_constants.end())
 312         {
 313                 lua_pushnumber(L, j->second);
 314                 return 1;
 315         }
 316
 317 #ifndef LUABIND_NO_ERROR_CHECKING
 318
 319         {
 320                 std::string msg = "no static '";
 321                 msg += key;
 322                 msg += "' in class '";
 323                 msg += crep->name();
 324                 msg += "'";
 325                 lua_pushstring(L, msg.c_str());
 326         }
 327         lua_error(L);
 328
 329 #endif
 330
 331         lua_pushnil(L);
 332
 333         return 1;
 334 }
 335
 336 bool luabind::detail::is_class_rep(lua_State* L, int index)
 337 {
 338         if (lua_getmetatable(L, index) == 0) return false;
 339
 340         lua_pushstring(L, "__luabind_classrep");
 341         lua_gettable(L, -2);
 342         if (lua_toboolean(L, -1))
 343         {
 344                 lua_pop(L, 2);
 345                 return true;
 346         }
 347
 348         lua_pop(L, 2);
 349         return false;
 350 }
 351
 352 void luabind::detail::finalize(lua_State* L, class_rep* crep)
 353 {
 354         if (crep->get_class_type() != class_rep::lua_class) return;
 355
 356 //      lua_pushvalue(L, -1); // copy the object ref
 357         crep->get_table(L);
 358         lua_pushstring(L, "__finalize");
 359         lua_gettable(L, -2);
 360         lua_remove(L, -2);
 361
 362         if (lua_isnil(L, -1))
 363         {
 364                 lua_pop(L, 1);
 365         }
 366         else
 367         {
 368                 lua_pushvalue(L, -2);
 369                 lua_call(L, 1, 0);
 370         }
 371
 372         for (std::vector<class_rep::base_info>::const_iterator
 373                         i = crep->bases().begin(); i != crep->bases().end(); ++i)
 374         {
 375                 if (i->base) finalize(L, i->base);
 376         }
 377 }
 378
 379 void luabind::detail::class_rep::cache_operators(lua_State* L)
 380 {
 381         m_operator_cache = 0x1;
 382
 383         for (int i = 0; i < number_of_operators; ++i)
 384         {
 385                 get_table(L);
 386                 lua_pushstring(L, get_operator_name(i));
 387                 lua_rawget(L, -2);
 388
 389                 if (lua_isfunction(L, -1)) m_operator_cache |= 1 << (i + 1);
 390
 391                 lua_pop(L, 2);
 392         }
 393 }
 394
 395 bool luabind::detail::class_rep::has_operator_in_lua(lua_State* L, int id)
 396 {
 397         if ((m_operator_cache & 0x1) == 0)
 398                 cache_operators(L);
 399
 400         const int mask = 1 << (id + 1);
 401
 402         return (m_operator_cache & mask) != 0;
 403 }