src/library/lua.cpp

   1 #include "lua-base.hpp"
   2 #include "lua-class.hpp"
   3 #include "lua-function.hpp"
   4 #include "lua-params.hpp"
   5 #include "lua-pin.hpp"
   6 #include "stateobject.hpp"
   7 #include "threads.hpp"
   8 #include <iostream>
   9 #include <cassert>
  10
  11 namespace lua
  12 {
  13 namespace
  14 {
  15         threads::rlock* global_lock;
  16         threads::rlock& get_lua_lock()
  17         {
  18                 if(!global_lock) global_lock = new threads::rlock;
  19                 return *global_lock;
  20         }
  21
  22         struct state_internal
  23         {
  24                 std::map<std::string, state::callback_list*> callbacks;
  25                 std::set<std::pair<function_group*, int>> function_groups;
  26                 std::set<std::pair<class_group*, int>> class_groups;
  27         };
  28
  29         struct fgroup_internal
  30         {
  31                 fgroup_internal()
  32                 {
  33                         next_handle = 0;
  34                 }
  35                 std::map<std::string, function*> functions;
  36                 int next_handle;
  37                 std::map<int, std::function<void(std::string, function*)>> callbacks;
  38                 std::map<int, std::function<void(function_group*)>> dcallbacks;
  39         };
  40
  41         struct cgroup_internal
  42         {
  43                 cgroup_internal()
  44                 {
  45                         next_handle = 0;
  46                 }
  47                 int next_handle;
  48                 std::map<std::string, class_base*> classes;
  49                 std::map<int, std::function<void(std::string, class_base*)>> callbacks;
  50                 std::map<int, std::function<void(class_group*)>> dcallbacks;
  51         };
  52
  53         typedef stateobject::type<state, state_internal> state_internal_t;
  54         typedef stateobject::type<function_group, fgroup_internal> fgroup_internal_t;
  55         typedef stateobject::type<class_group, cgroup_internal> cgroup_internal_t;
  56 }
  57
  58 std::unordered_map<std::type_index, void*>& class_types()
  59 {
  60         static std::unordered_map<std::type_index, void*> x;
  61         return x;
  62 }
  63 namespace
  64 {
  65         char classtable_key;
  66         char classtable_meta_key;
  67
  68         struct class_info
  69         {
  70                 class_base* obj;
  71                 static int index(lua_State* L);
  72                 static int newindex(lua_State* L);
  73                 static int pairs(lua_State* L);
  74                 static int pairs_next(lua_State* L);
  75                 static int smethods(lua_State* L);
  76                 static int cmethods(lua_State* L);
  77                 static int trampoline(lua_State* L);
  78                 static void check(lua_State* L);
  79         };
  80
  81         void class_info::check(lua_State* L)
  82         {
  83                 lua_pushlightuserdata(L, &classtable_meta_key);
  84                 lua_rawget(L, LUA_REGISTRYINDEX);
  85                 lua_getmetatable(L, 1);
  86                 if(!lua_rawequal(L, -1, -2)) {
  87                         lua_pushstring(L, "Bad class table");
  88                         lua_error(L);
  89                 }
  90                 lua_pop(L, 2);
  91         }
  92
  93         int class_info::index(lua_State* L)
  94         {
  95                 check(L);
  96
  97                 class_base* ptr = ((class_info*)lua_touserdata(L, 1))->obj;
  98                 const char* method = lua_tostring(L, 2);
  99                 if(!method) {
 100                         lua_pushstring(L, "Indexing invalid element of class table");
 101                         lua_error(L);
 102                 }
 103                 if(!strcmp(method, "_static_methods")) {
 104                         lua_pushlightuserdata(L, ptr);
 105                         lua_pushcclosure(L, class_info::smethods, 1);
 106                         return 1;
 107                 } else if(!strcmp(method, "_class_methods")) {
 108                         lua_pushlightuserdata(L, ptr);
 109                         lua_pushcclosure(L, class_info::cmethods, 1);
 110                         return 1;
 111                 } else {
 112                         auto m = ptr->static_methods();
 113                         for(auto i : m) {
 114                                 if(!strcmp(i.name, method)) {
 115                                         //Hit.
 116                                         std::string name = ptr->get_name() + "::" + method;
 117                                         lua_pushvalue(L, lua_upvalueindex(1));  //State.
 118                                         lua_pushlightuserdata(L, (void*)i.fn);
 119                                         std::string fname = ptr->get_name() + "::" + i.name;
 120                                         lua_pushstring(L, fname.c_str());
 121                                         lua_pushcclosure(L, class_info::trampoline, 3);
 122                                         return 1;
 123                                 }
 124                         }
 125                         std::string err = std::string("Class '") + ptr->get_name() +
 126                                 "' does not have static method '" + method + "'";
 127                         lua_pushstring(L, err.c_str());
 128                         lua_error(L);
 129                 }
 130                 return 0; //NOTREACHED
 131         }
 132         int class_info::newindex(lua_State* L)
 133         {
 134                 lua_pushstring(L, "Writing into class table not allowed");
 135                 lua_error(L);
 136                 return 0; //NOTREACHED
 137         }
 138
 139         int class_info::pairs(lua_State* _xL)
 140         {
 141                 check(_xL);
 142
 143                 lua::state* _L = (lua::state*)lua_touserdata(_xL, lua_upvalueindex(1));
 144                 state L(*_L, _xL);
 145
 146                 L.pushvalue(lua_upvalueindex(1));
 147                 L.pushcclosure(class_info::pairs_next, 1);      //Next
 148                 L.pushvalue(1);                                 //State.
 149                 L.pushnil();                                    //Index.
 150                 return 3;
 151         }
 152
 153         int class_info::pairs_next(lua_State* _xL)
 154         {
 155                 check(_xL);
 156
 157                 lua::state* _L = (lua::state*)lua_touserdata(_xL, lua_upvalueindex(1));
 158                 state L(*_L, _xL);
 159                 class_base* obj = ((class_info*)L.touserdata(1))->obj;
 160                 auto m = obj->static_methods();
 161                 std::string key = (L.type(2) == LUA_TSTRING) ? L.tostring(2) : "";
 162                 std::string lowbound = "\xFF";  //Sorts greater than anything that is valid UTF-8.
 163                 void* best_fn = NULL;
 164                 for(auto i : m)
 165                         if(lowbound > i.name && i.name > key) {
 166                                 lowbound = i.name;
 167                                 best_fn = (void*)i.fn;
 168                         }
 169                 if(best_fn) {
 170                         L.pushlstring(lowbound);
 171                         std::string name = obj->get_name() + "::" + lowbound;
 172                         L.pushvalue(lua_upvalueindex(1));  //State.
 173                         L.pushlightuserdata(best_fn);
 174                         L.pushlstring(name);
 175                         L.pushcclosure(class_info::trampoline, 3);
 176                         return 2;
 177                 } else {
 178                         L.pushnil();
 179                         return 1;
 180                 }
 181         }
 182
 183         int class_info::smethods(lua_State* L)
 184         {
 185                 class_base* obj = (class_base*)lua_touserdata(L, lua_upvalueindex(1));
 186                 auto m = obj->static_methods();
 187                 int rets = 0;
 188                 for(auto i : m) {
 189                         lua_pushstring(L, i.name);
 190                         rets++;
 191                 }
 192                 return rets;
 193         }
 194
 195         int class_info::cmethods(lua_State* L)
 196         {
 197                 class_base* obj = (class_base*)lua_touserdata(L, lua_upvalueindex(1));
 198                 auto m = obj->class_methods();
 199                 int rets = 0;
 200                 for(auto i : m) {
 201                         lua_pushstring(L, i.c_str());
 202                         rets++;
 203                 }
 204                 return rets;
 205         }
 206
 207         typedef int (*fn_t)(state& L, parameters& P);
 208
 209         int class_info::trampoline(lua_State* L)
 210         {
 211                 state* lstate = reinterpret_cast<state*>(lua_touserdata(L, lua_upvalueindex(1)));
 212                 void* _fn = lua_touserdata(L, lua_upvalueindex(2));
 213                 fn_t fn = (fn_t)_fn;
 214                 try {
 215                         std::string name = lua_tostring(L, lua_upvalueindex(3));
 216                         state _L(*lstate, L);
 217                         parameters P(_L, name);
 218                         return fn(_L, P);
 219                 } catch(std::exception& e) {
 220                         lua_pushfstring(L, "%s", e.what());
 221                         lua_error(L);
 222                 }
 223                 return 0;
 224         }
 225
 226         int lua_trampoline_function(lua_State* L)
 227         {
 228                 void* ptr = lua_touserdata(L, lua_upvalueindex(1));
 229                 state* lstate = reinterpret_cast<state*>(lua_touserdata(L, lua_upvalueindex(2)));
 230                 function* f = reinterpret_cast<function*>(ptr);
 231                 try {
 232                         state _L(*lstate, L);
 233                         return f->invoke(_L);
 234                 } catch(std::exception& e) {
 235                         lua_pushfstring(L, "%s", e.what());
 236                         lua_error(L);
 237                 }
 238                 return 0;
 239         }
 240
 241         //Pushes given table to top of stack, creating if needed.
 242         void recursive_lookup_table(state& L, const std::string& tab)
 243         {
 244                 if(tab == "") {
 245                         L.pushglobals();
 246                         assert(L.type(-1) == LUA_TTABLE);
 247                         return;
 248                 }
 249                 std::string u = tab;
 250                 size_t split = u.find_last_of(".");
 251                 std::string u1;
 252                 std::string u2 = u;
 253                 if(split < u.length()) {
 254                         u1 = u.substr(0, split);
 255                         u2 = u.substr(split + 1);
 256                 }
 257                 recursive_lookup_table(L, u1);
 258                 L.getfield(-1, u2.c_str());
 259                 if(L.type(-1) != LUA_TTABLE) {
 260                         //Not a table, create a table.
 261                         L.pop(1);
 262                         L.newtable();
 263                         L.setfield(-2, u2.c_str());
 264                         L.getfield(-1, u2.c_str());
 265                 }
 266                 //Get rid of previous table.
 267                 L.insert(-2);
 268                 L.pop(1);
 269         }
 270
 271         void register_function(state& L, const std::string& name, function* fun)
 272         {
 273                 std::string u = name;
 274                 size_t split = u.find_last_of(".");
 275                 std::string u1;
 276                 std::string u2 = u;
 277                 if(split < u.length()) {
 278                         u1 = u.substr(0, split);
 279                         u2 = u.substr(split + 1);
 280                 }
 281                 recursive_lookup_table(L, u1);
 282                 if(!fun)
 283                         L.pushnil();
 284                 else {
 285                         void* ptr = reinterpret_cast<void*>(fun);
 286                         L.pushlightuserdata(ptr);
 287                         L.pushlightuserdata(&L);
 288                         L.pushcclosure(lua_trampoline_function, 2);
 289                 }
 290                 L.setfield(-2, u2.c_str());
 291                 L.pop(1);
 292         }
 293
 294         void register_class(state& L, const std::string& name, class_base* fun)
 295         {
 296                 fun->register_state(L);
 297         }
 298 }
 299
 300 state::state() throw(std::bad_alloc)
 301 {
 302         master = NULL;
 303         lua_handle = NULL;
 304         oom_handler = builtin_oom;
 305 }
 306
 307 state::state(state& _master, lua_State* L)
 308 {
 309         master = &_master;
 310         lua_handle = L;
 311 }
 312
 313 state::~state() throw()
 314 {
 315         if(master)
 316                 return;
 317         threads::arlock h(get_lua_lock());
 318         auto state = state_internal_t::get_soft(this);
 319         if(!state) return;
 320         for(auto i : state->function_groups)
 321                 i.first->drop_callback(i.second);
 322         for(auto i : state->class_groups)
 323                 i.first->drop_callback(i.second);
 324         if(lua_handle)
 325                 lua_close(lua_handle);
 326         state_internal_t::clear(this);
 327 }
 328
 329 void state::builtin_oom()
 330 {
 331         std::cerr << "PANIC: FATAL: Out of memory" << std::endl;
 332         exit(1);
 333 }
 334
 335 void* state::builtin_alloc(void* user, void* old, size_t olds, size_t news)
 336 {
 337         if(news) {
 338                 void* m = realloc(old, news);
 339                 if(!m)
 340                         reinterpret_cast<state*>(user)->oom_handler();
 341                 return m;
 342         } else
 343                 free(old);
 344         return NULL;
 345 }
 346
 347
 348 function::function(function_group& _group, const std::string& func) throw(std::bad_alloc)
 349         : group(_group)
 350 {
 351         group.do_register(fname = func, *this);
 352 }
 353
 354 function::~function() throw()
 355 {
 356         group.do_unregister(fname, *this);
 357 }
 358
 359 class_base::class_base(class_group& _group, const std::string& _name)
 360         : group(_group), name(_name)
 361 {
 362         registered = false;
 363 }
 364
 365 class_base::~class_base() throw()
 366 {
 367         if(registered)
 368                 group.do_unregister(name, *this);
 369 }
 370
 371 void state::reset() throw(std::bad_alloc, std::runtime_error)
 372 {
 373         if(master)
 374                 return master->reset();
 375         threads::arlock h(get_lua_lock());
 376         auto state = &state_internal_t::get(this);
 377         if(lua_handle) {
 378                 lua_State* tmp = lua_newstate(state::builtin_alloc, this);
 379                 if(!tmp)
 380                         throw std::runtime_error("Can't re-initialize Lua interpretter");
 381                 lua_close(lua_handle);
 382                 for(auto& i : state->callbacks)
 383                         i.second->clear();
 384                 lua_handle = tmp;
 385         } else {
 386                 //Initialize new.
 387                 lua_handle = lua_newstate(state::builtin_alloc, this);
 388                 if(!lua_handle)
 389                         throw std::runtime_error("Can't initialize Lua interpretter");
 390         }
 391         for(auto i : state->function_groups)
 392                 i.first->request_callback([this](std::string name, function* func) -> void {
 393                         register_function(*this, name, func);
 394                 });
 395         for(auto i : state->class_groups)
 396                 i.first->request_callback([this](std::string name, class_base* clazz) -> void {
 397                         register_class(*this, name, clazz);
 398                 });
 399 }
 400
 401 void state::deinit() throw()
 402 {
 403         if(master)
 404                 return master->deinit();
 405         if(lua_handle)
 406                 lua_close(lua_handle);
 407         lua_handle = NULL;
 408 }
 409
 410 void state::add_function_group(function_group& group)
 411 {
 412         threads::arlock h(get_lua_lock());
 413         auto& state = state_internal_t::get(this);
 414         state.function_groups.insert(std::make_pair(&group, group.add_callback([this](const std::string& name,
 415                 function* func) -> void {
 416                 this->function_callback(name, func);
 417         }, [this](function_group* x) {
 418                 threads::arlock h(get_lua_lock());
 419                 auto state = state_internal_t::get_soft(this);
 420                 if(!state) return;
 421                 for(auto i = state->function_groups.begin(); i != state->function_groups.end();)
 422                         if(i->first == x)
 423                                 i = state->function_groups.erase(i);
 424                         else
 425                                 i++;
 426         })));
 427 }
 428
 429 void state::add_class_group(class_group& group)
 430 {
 431         threads::arlock h(get_lua_lock());
 432         auto& state = state_internal_t::get(this);
 433         state.class_groups.insert(std::make_pair(&group, group.add_callback([this](const std::string& name,
 434                 class_base* clazz) -> void {
 435                 this->class_callback(name, clazz);
 436         }, [this](class_group* x) {
 437                 threads::arlock h(get_lua_lock());
 438                 auto state = state_internal_t::get_soft(this);
 439                 if(!state) return;
 440                 for(auto i = state->class_groups.begin(); i != state->class_groups.end();)
 441                         if(i->first == x)
 442                                 i = state->class_groups.erase(i);
 443                         else
 444                                 i++;
 445         })));
 446 }
 447
 448 void state::function_callback(const std::string& name, function* func)
 449 {
 450         if(master)
 451                 return master->function_callback(name, func);
 452         if(lua_handle)
 453                 register_function(*this, name, func);
 454 }
 455
 456 void state::class_callback(const std::string& name, class_base* clazz)
 457 {
 458         if(master)
 459                 return master->class_callback(name, clazz);
 460         if(lua_handle)
 461                 register_class(*this, name, clazz);
 462 }
 463
 464 bool state::do_once(void* key)
 465 {
 466         if(master)
 467                 return master->do_once(key);
 468         pushlightuserdata(key);
 469         rawget(LUA_REGISTRYINDEX);
 470         if(type(-1) == LUA_TNIL) {
 471                 pop(1);
 472                 pushlightuserdata(key);
 473                 pushlightuserdata(key);
 474                 rawset(LUA_REGISTRYINDEX);
 475                 return true;
 476         } else {
 477                 pop(1);
 478                 return false;
 479         }
 480 }
 481
 482 std::list<state::callback_list*> state::get_callbacks()
 483 {
 484         if(master)
 485                 return master->get_callbacks();
 486         threads::arlock h(get_lua_lock());
 487         auto state = state_internal_t::get_soft(this);
 488         std::list<callback_list*> r;
 489         if(state)
 490                 for(auto i : state->callbacks)
 491                         r.push_back(i.second);
 492         return r;
 493 }
 494
 495 void state::do_register(const std::string& name, callback_list& callback)
 496 {
 497         threads::arlock h(get_lua_lock());
 498         auto& state = state_internal_t::get(this);
 499         if(state.callbacks.count(name)) return;
 500         state.callbacks[name] = &callback;
 501 }
 502
 503 void state::do_unregister(const std::string& name, callback_list& callback)
 504 {
 505         threads::arlock h(get_lua_lock());
 506         auto state = state_internal_t::get_soft(this);
 507         if(state && state->callbacks.count(name) && state->callbacks[name] == &callback)
 508                 state->callbacks.erase(name);
 509 }
 510
 511 state::callback_list::callback_list(state& _L, const std::string& _name, const std::string& fncbname)
 512         : L(_L), name(_name), fn_cbname(fncbname)
 513 {
 514         L.do_register(name, *this);
 515 }
 516
 517 state::callback_list::~callback_list()
 518 {
 519         L.do_unregister(name, *this);
 520         if(!L.handle())
 521                 return;
 522         for(auto& i : callbacks) {
 523                 L.pushlightuserdata(&i);
 524                 L.pushnil();
 525                 L.rawset(LUA_REGISTRYINDEX);
 526         }
 527 }
 528
 529 void state::callback_list::_register(state& _L)
 530 {
 531         callbacks.push_back(0);
 532         _L.pushlightuserdata(&*callbacks.rbegin());
 533         _L.pushvalue(-2);
 534         _L.rawset(LUA_REGISTRYINDEX);
 535 }
 536
 537 void state::callback_list::_unregister(state& _L)
 538 {
 539         for(auto i = callbacks.begin(); i != callbacks.end();) {
 540                 _L.pushlightuserdata(&*i);
 541                 _L.rawget(LUA_REGISTRYINDEX);
 542                 if(_L.rawequal(-1, -2)) {
 543                         char* key = &*i;
 544                         _L.pushlightuserdata(key);
 545                         _L.pushnil();
 546                         _L.rawset(LUA_REGISTRYINDEX);
 547                         i = callbacks.erase(i);
 548                 } else
 549                         i++;
 550                 _L.pop(1);
 551         }
 552 }
 553
 554 function_group::function_group()
 555 {
 556 }
 557
 558 function_group::~function_group()
 559 {
 560         threads::arlock h(get_lua_lock());
 561         auto state = fgroup_internal_t::get_soft(this);
 562         if(!state) return;
 563         for(auto i : state->dcallbacks)
 564                 i.second(this);
 565         fgroup_internal_t::clear(this);
 566 }
 567
 568 void function_group::request_callback(std::function<void(std::string, function*)> cb)
 569 {
 570         threads::arlock h(get_lua_lock());
 571         auto state = fgroup_internal_t::get_soft(this);
 572         if(!state) return;
 573         for(auto i : state->functions)
 574                 cb(i.first, i.second);
 575 }
 576
 577 int function_group::add_callback(std::function<void(std::string, function*)> cb,
 578         std::function<void(function_group*)> dcb)
 579 {
 580         threads::arlock h(get_lua_lock());
 581         auto& state = fgroup_internal_t::get(this);
 582         int handle = state.next_handle++;
 583         state.callbacks[handle] = cb;
 584         state.dcallbacks[handle] = dcb;
 585         for(auto i : state.functions)
 586                 cb(i.first, i.second);
 587         return handle;
 588 }
 589
 590 void function_group::drop_callback(int handle)
 591 {
 592         threads::arlock h(get_lua_lock());
 593         auto state = fgroup_internal_t::get_soft(this);
 594         if(!state) return;
 595         state->callbacks.erase(handle);
 596 }
 597
 598 void function_group::do_register(const std::string& name, function& fun)
 599 {
 600         threads::arlock h(get_lua_lock());
 601         auto& state = fgroup_internal_t::get(this);
 602         if(state.functions.count(name)) return;
 603         state.functions[name] = &fun;
 604         for(auto i : state.callbacks)
 605                 i.second(name, &fun);
 606 }
 607
 608 void function_group::do_unregister(const std::string& name, function& fun)
 609 {
 610         threads::arlock h(get_lua_lock());
 611         auto state = fgroup_internal_t::get_soft(this);
 612         if(!state || !state->functions.count(name) || state->functions[name] != &fun) return;
 613         state->functions.erase(name);
 614         for(auto i : state->callbacks)
 615                 i.second(name, NULL);
 616 }
 617
 618 class_group::class_group()
 619 {
 620 }
 621
 622 class_group::~class_group()
 623 {
 624         threads::arlock h(get_lua_lock());
 625         auto state = cgroup_internal_t::get_soft(this);
 626         if(!state) return;
 627         for(auto i : state->dcallbacks)
 628                 i.second(this);
 629         cgroup_internal_t::clear(this);
 630 }
 631
 632 void class_group::request_callback(std::function<void(std::string, class_base*)> cb)
 633 {
 634         threads::arlock h(get_lua_lock());
 635         auto state = cgroup_internal_t::get_soft(this);
 636         if(!state) return;
 637         for(auto i : state->classes)
 638                 cb(i.first, i.second);
 639 }
 640
 641 int class_group::add_callback(std::function<void(std::string, class_base*)> cb,
 642         std::function<void(class_group*)> dcb)
 643 {
 644         threads::arlock h(get_lua_lock());
 645         auto& state = cgroup_internal_t::get(this);
 646         int handle = state.next_handle++;
 647         state.callbacks[handle] = cb;
 648         state.dcallbacks[handle] = dcb;
 649         for(auto i : state.classes)
 650                 cb(i.first, i.second);
 651         return handle;
 652 }
 653
 654 void class_group::drop_callback(int handle)
 655 {
 656         threads::arlock h(get_lua_lock());
 657         auto state = cgroup_internal_t::get_soft(this);
 658         if(!state) return;
 659         state->callbacks.erase(handle);
 660 }
 661
 662 void class_group::do_register(const std::string& name, class_base& fun)
 663 {
 664         threads::arlock h(get_lua_lock());
 665         auto& state = cgroup_internal_t::get(this);
 666         if(state.classes.count(name)) return;
 667         state.classes[name] = &fun;
 668         for(auto i : state.callbacks)
 669                 i.second(name, &fun);
 670 }
 671
 672 void class_group::do_unregister(const std::string& name, class_base& fun)
 673 {
 674         threads::arlock h(get_lua_lock());
 675         auto state = cgroup_internal_t::get_soft(this);
 676         if(!state || !state->classes.count(name) || state->classes[name] != &fun) return;
 677         state->classes.erase(name);
 678         for(auto i : state->callbacks)
 679                 i.second(name, NULL);
 680 }
 681
 682 std::list<class_ops>& userdata_recogn_fns()
 683 {
 684         static std::list<class_ops> x;
 685         return x;
 686 }
 687
 688 std::string try_recognize_userdata(state& state, int index)
 689 {
 690         for(auto i : userdata_recogn_fns())
 691                 if(i.is(state, index))
 692                         return i.name();
 693         //Hack: Lua builtin file objects and classobjs.
 694         if(state.getmetatable(index)) {
 695                 state.pushstring("FILE*");
 696                 state.rawget(LUA_REGISTRYINDEX);
 697                 if(state.rawequal(-1, -2)) {
 698                         state.pop(2);
 699                         return "FILE*";
 700                 }
 701                 state.pop(1);
 702                 state.pushlightuserdata(&classtable_meta_key);
 703                 state.rawget(LUA_REGISTRYINDEX);
 704                 if(state.rawequal(-1, -2)) {
 705                         state.pop(2);
 706                         return "classobj";
 707                 }
 708                 state.pop(1);
 709         }
 710         return "unknown";
 711 }
 712
 713 std::string try_print_userdata(state& L, int index)
 714 {
 715         for(auto i : userdata_recogn_fns())
 716                 if(i.is(L, index))
 717                         return i.print(L, index);
 718         //Hack: classobjs.
 719         if(L.getmetatable(index)) {
 720                 L.pushlightuserdata(&classtable_meta_key);
 721                 L.rawget(LUA_REGISTRYINDEX);
 722                 if(L.rawequal(-1, -2)) {
 723                         L.pop(2);
 724                         std::string cname = ((class_info*)L.touserdata(index))->obj->get_name();
 725                         return cname;
 726                 }
 727                 L.pop(1);
 728         }
 729         return "no data available";
 730 }
 731
 732 int state::vararg_tag::pushargs(state& L)
 733 {
 734         int e = 0;
 735         for(auto i : args) {
 736                 if(i == "")
 737                         L.pushnil();
 738                 else if(i == "true")
 739                         L.pushboolean(true);
 740                 else if(i == "false")
 741                         L.pushboolean(false);
 742                 else if(regex_match("[+-]?(|0|[1-9][0-9]*)(.[0-9]+)?([eE][+-]?(0|[1-9][0-9]*))?", i))
 743                         L.pushnumber(strtod(i.c_str(), NULL));
 744                 else if(i[0] == ':')
 745                         L.pushlstring(i.substr(1));
 746                 else
 747                         L.pushlstring(i);
 748                 e++;
 749         }
 750         return e;
 751 }
 752
 753 class_base* class_base::lookup(state& L, const std::string& _name)
 754 {
 755         if(lookup_and_push(L, _name)) {
 756                 class_base* obj = ((class_info*)L.touserdata(-1))->obj;
 757                 L.pop(1);
 758                 return obj;
 759         }
 760         return NULL;
 761 }
 762
 763 bool class_base::lookup_and_push(state& L, const std::string& _name)
 764 {
 765         L.pushlightuserdata(&classtable_key);
 766         L.rawget(LUA_REGISTRYINDEX);
 767         if(L.type(-1) == LUA_TNIL) {
 768                 //No classes.
 769                 L.pop(1);
 770                 return false;
 771         }
 772         //On top of stack there is class table.
 773         L.pushlstring(_name);
 774         L.rawget(-2);
 775         if(L.type(-1) == LUA_TNIL) {
 776                 //Not found.
 777                 L.pop(2);
 778                 return false;
 779         }
 780         L.insert(-2);
 781         L.pop(1);
 782         return true;
 783 }
 784
 785 std::set<std::string> class_base::all_classes(state& L)
 786 {
 787         L.pushlightuserdata(&classtable_key);
 788         L.rawget(LUA_REGISTRYINDEX);
 789         if(L.type(-1) == LUA_TNIL) {
 790                 //No classes.
 791                 L.pop(1);
 792                 return std::set<std::string>();
 793         }
 794         std::set<std::string> r;
 795         L.pushnil();
 796         while(L.next(-2)) {
 797                 L.pop(1);       //Pop value.
 798                 if(L.type(-1) == LUA_TSTRING) r.insert(L.tostring(-1));
 799         }
 800         L.pop(1);
 801         return r;
 802 }
 803
 804 void class_base::register_static(state& L)
 805 {
 806 again:
 807         L.pushlightuserdata(&classtable_key);
 808         L.rawget(LUA_REGISTRYINDEX);
 809         if(L.type(-1) == LUA_TNIL) {
 810                 L.pop(1);
 811                 L.pushlightuserdata(&classtable_key);
 812                 L.newtable();
 813                 L.rawset(LUA_REGISTRYINDEX);
 814                 goto again;
 815         }
 816         //On top of stack there is class table.
 817         L.pushlstring(name);
 818         L.rawget(-2);
 819         if(L.type(-1) != LUA_TNIL) {
 820                 //Already registered.
 821                 L.pop(2);
 822                 return;
 823         }
 824         L.pop(1);
 825         L.pushlstring(name);
 826         //Now construct the object.
 827         class_info* ci = (class_info*)L.newuserdata(sizeof(class_info));
 828         ci->obj = this;
 829 again2:
 830         L.pushlightuserdata(&classtable_meta_key);
 831         L.rawget(LUA_REGISTRYINDEX);
 832         if(L.type(-1) == LUA_TNIL) {
 833                 L.pop(1);
 834                 L.pushlightuserdata(&classtable_meta_key);
 835                 L.newtable();
 836                 L.pushstring("__index");
 837                 L.pushlightuserdata(&L);
 838                 L.pushcclosure(class_info::index, 1);
 839                 L.rawset(-3);
 840                 L.pushstring("__newindex");
 841                 L.pushcfunction(class_info::newindex);
 842                 L.rawset(-3);
 843                 L.pushstring("__pairs");
 844                 L.pushlightuserdata(&L);
 845                 L.pushcclosure(class_info::pairs, 1);
 846                 L.rawset(-3);
 847                 L.rawset(LUA_REGISTRYINDEX);
 848                 goto again2;
 849         }
 850         L.setmetatable(-2);
 851         L.rawset(-3);
 852         L.pop(1);
 853 }
 854
 855 void class_base::delayed_register()
 856 {
 857         group.do_register(name, *this);
 858 }
 859
 860 functions::functions(function_group& grp, const std::string& basetable, std::initializer_list<entry> fnlist)
 861 {
 862         std::string base = (basetable == "") ? "" : (basetable + ".");
 863         for(auto i : fnlist)
 864                 funcs.insert(new fn(grp, base + i.name, i.func));
 865 }
 866
 867 functions::~functions()
 868 {
 869         for(auto i : funcs)
 870                 delete i;
 871 }
 872
 873 functions::fn::fn(function_group& grp, const std::string& name, std::function<int(state& L, parameters& P)> _func)
 874         : function(grp, name)
 875 {
 876         func = _func;
 877 }
 878
 879 functions::fn::~fn() throw()
 880 {
 881 }
 882
 883 int functions::fn::invoke(state& L)
 884 {
 885         lua::parameters P(L, fname);
 886         return func(L, P);
 887 }
 888 }