src/loadlib.c

   1 /*
   2 ** $Id: loadlib.c,v 1.54a 2006/07/03 20:16:49 roberto Exp $
   3 ** Dynamic library loader for Lua
   4 ** See Copyright Notice in lua.h
   5 **
   6 ** This module contains an implementation of loadlib for Unix systems
   7 ** that have dlfcn, an implementation for Darwin (Mac OS X), an
   8 ** implementation for Windows, and a stub for other systems.
   9 */
  10
  11
  12 #include <stdlib.h>
  13 #include <string.h>
  14
  15
  16 #define loadlib_c
  17 #define LUA_LIB
  18
  19 #include "lua.h"
  20
  21 #include "lauxlib.h"
  22 #include "lualib.h"
  23
  24
  25 /* prefix for open functions in C libraries */
  26 #define LUA_POF         "luaopen_"
  27
  28 /* separator for open functions in C libraries */
  29 #define LUA_OFSEP       "_"
  30
  31
  32 #define LIBPREFIX       "LOADLIB: "
  33
  34 #define POF             LUA_POF
  35 #define LIB_FAIL        "open"
  36
  37
  38 /* error codes for ll_loadfunc */
  39 #define ERRLIB          1
  40 #define ERRFUNC         2
  41
  42 #define setprogdir(L)           ((void)0)
  43
  44
  45 static void ll_unloadlib (void *lib);
  46 static void *ll_load (lua_State *L, const char *path);
  47 static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym);
  48
  49
  50
  51 #if defined(LUA_DL_DLOPEN)
  52 /*
  53 ** {========================================================================
  54 ** This is an implementation of loadlib based on the dlfcn interface.
  55 ** The dlfcn interface is available in Linux, SunOS, Solaris, IRIX, FreeBSD,
  56 ** NetBSD, AIX 4.2, HPUX 11, and  probably most other Unix flavors, at least
  57 ** as an emulation layer on top of native functions.
  58 ** =========================================================================
  59 */
  60
  61 #include <dlfcn.h>
  62
  63 static void ll_unloadlib (void *lib) {
  64   dlclose(lib);
  65 }
  66
  67
  68 static void *ll_load (lua_State *L, const char *path) {
  69   void *lib = dlopen(path, RTLD_NOW);
  70   if (lib == NULL) lua_pushstring(L, dlerror());
  71   return lib;
  72 }
  73
  74
  75 static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
  76   lua_CFunction f = (lua_CFunction)dlsym(lib, sym);
  77   if (f == NULL) lua_pushstring(L, dlerror());
  78   return f;
  79 }
  80
  81 /* }====================================================== */
  82
  83
  84
  85 #elif defined(LUA_DL_DLL)
  86 /*
  87 ** {======================================================================
  88 ** This is an implementation of loadlib for Windows using native functions.
  89 ** =======================================================================
  90 */
  91
  92 #include <windows.h>
  93
  94
  95 #undef setprogdir
  96
  97 static void setprogdir (lua_State *L) {
  98   char buff[MAX_PATH + 1];
  99   char *lb;
 100   DWORD nsize = sizeof(buff)/sizeof(char);
 101   DWORD n = GetModuleFileNameA(NULL, buff, nsize);
 102   if (n == 0 || n == nsize || (lb = strrchr(buff, '\\')) == NULL)
 103     luaL_error(L, "unable to get ModuleFileName");
 104   else {
 105     *lb = '\0';
 106     luaL_gsub(L, lua_tostring(L, -1), LUA_EXECDIR, buff);
 107     lua_remove(L, -2);  /* remove original string */
 108   }
 109 }
 110
 111
 112 static void pusherror (lua_State *L) {
 113   int error = GetLastError();
 114   char buffer[128];
 115   if (FormatMessageA(FORMAT_MESSAGE_IGNORE_INSERTS | FORMAT_MESSAGE_FROM_SYSTEM,
 116       NULL, error, 0, buffer, sizeof(buffer), NULL))
 117     lua_pushstring(L, buffer);
 118   else
 119     lua_pushfstring(L, "system error %d\n", error);
 120 }
 121
 122 static void ll_unloadlib (void *lib) {
 123   FreeLibrary((HINSTANCE)lib);
 124 }
 125
 126
 127 static void *ll_load (lua_State *L, const char *path) {
 128   HINSTANCE lib = LoadLibraryA(path);
 129   if (lib == NULL) pusherror(L);
 130   return lib;
 131 }
 132
 133
 134 static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
 135   lua_CFunction f = (lua_CFunction)GetProcAddress((HINSTANCE)lib, sym);
 136   if (f == NULL) pusherror(L);
 137   return f;
 138 }
 139
 140 /* }====================================================== */
 141
 142
 143
 144 #elif defined(LUA_DL_DYLD)
 145 /*
 146 ** {======================================================================
 147 ** Native Mac OS X / Darwin Implementation
 148 ** =======================================================================
 149 */
 150
 151 #include <mach-o/dyld.h>
 152
 153
 154 /* Mac appends a `_' before C function names */
 155 #undef POF
 156 #define POF     "_" LUA_POF
 157
 158
 159 static void pusherror (lua_State *L) {
 160   const char *err_str;
 161   const char *err_file;
 162   NSLinkEditErrors err;
 163   int err_num;
 164   NSLinkEditError(&err, &err_num, &err_file, &err_str);
 165   lua_pushstring(L, err_str);
 166 }
 167
 168
 169 static const char *errorfromcode (NSObjectFileImageReturnCode ret) {
 170   switch (ret) {
 171     case NSObjectFileImageInappropriateFile:
 172       return "file is not a bundle";
 173     case NSObjectFileImageArch:
 174       return "library is for wrong CPU type";
 175     case NSObjectFileImageFormat:
 176       return "bad format";
 177     case NSObjectFileImageAccess:
 178       return "cannot access file";
 179     case NSObjectFileImageFailure:
 180     default:
 181       return "unable to load library";
 182   }
 183 }
 184
 185
 186 static void ll_unloadlib (void *lib) {
 187   NSUnLinkModule((NSModule)lib, NSUNLINKMODULE_OPTION_RESET_LAZY_REFERENCES);
 188 }
 189
 190
 191 static void *ll_load (lua_State *L, const char *path) {
 192   NSObjectFileImage img;
 193   NSObjectFileImageReturnCode ret;
 194   /* this would be a rare case, but prevents crashing if it happens */
 195   if(!_dyld_present()) {
 196     lua_pushliteral(L, "dyld not present");
 197     return NULL;
 198   }
 199   ret = NSCreateObjectFileImageFromFile(path, &img);
 200   if (ret == NSObjectFileImageSuccess) {
 201     NSModule mod = NSLinkModule(img, path, NSLINKMODULE_OPTION_PRIVATE |
 202                        NSLINKMODULE_OPTION_RETURN_ON_ERROR);
 203     NSDestroyObjectFileImage(img);
 204     if (mod == NULL) pusherror(L);
 205     return mod;
 206   }
 207   lua_pushstring(L, errorfromcode(ret));
 208   return NULL;
 209 }
 210
 211
 212 static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
 213   NSSymbol nss = NSLookupSymbolInModule((NSModule)lib, sym);
 214   if (nss == NULL) {
 215     lua_pushfstring(L, "symbol " LUA_QS " not found", sym);
 216     return NULL;
 217   }
 218   return (lua_CFunction)NSAddressOfSymbol(nss);
 219 }
 220
 221 /* }====================================================== */
 222
 223
 224
 225 #else
 226 /*
 227 ** {======================================================
 228 ** Fallback for other systems
 229 ** =======================================================
 230 */
 231
 232 #undef LIB_FAIL
 233 #define LIB_FAIL        "absent"
 234
 235
 236 #define DLMSG   "dynamic libraries not enabled; check your Lua installation"
 237
 238
 239 static void ll_unloadlib (void *lib) {
 240   (void)lib;  /* to avoid warnings */
 241 }
 242
 243
 244 static void *ll_load (lua_State *L, const char *path) {
 245   (void)path;  /* to avoid warnings */
 246   lua_pushliteral(L, DLMSG);
 247   return NULL;
 248 }
 249
 250
 251 static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
 252   (void)lib; (void)sym;  /* to avoid warnings */
 253   lua_pushliteral(L, DLMSG);
 254   return NULL;
 255 }
 256
 257 /* }====================================================== */
 258 #endif
 259
 260
 261
 262 static void **ll_register (lua_State *L, const char *path) {
 263   void **plib;
 264   lua_pushfstring(L, "%s%s", LIBPREFIX, path);
 265   lua_gettable(L, LUA_REGISTRYINDEX);  /* check library in registry? */
 266   if (!lua_isnil(L, -1))  /* is there an entry? */
 267     plib = (void **)lua_touserdata(L, -1);
 268   else {  /* no entry yet; create one */
 269     lua_pop(L, 1);
 270     plib = (void **)lua_newuserdata(L, sizeof(const void *));
 271     *plib = NULL;
 272     luaL_getmetatable(L, "_LOADLIB");
 273     lua_setmetatable(L, -2);
 274     lua_pushfstring(L, "%s%s", LIBPREFIX, path);
 275     lua_pushvalue(L, -2);
 276     lua_settable(L, LUA_REGISTRYINDEX);
 277   }
 278   return plib;
 279 }
 280
 281
 282 /*
 283 ** __gc tag method: calls library's `ll_unloadlib' function with the lib
 284 ** handle
 285 */
 286 static int gctm (lua_State *L) {
 287   void **lib = (void **)luaL_checkudata(L, 1, "_LOADLIB");
 288   if (*lib) ll_unloadlib(*lib);
 289   *lib = NULL;  /* mark library as closed */
 290   return 0;
 291 }
 292
 293
 294 static int ll_loadfunc (lua_State *L, const char *path, const char *sym) {
 295   void **reg = ll_register(L, path);
 296   if (*reg == NULL) *reg = ll_load(L, path);
 297   if (*reg == NULL)
 298     return ERRLIB;  /* unable to load library */
 299   else {
 300     lua_CFunction f = ll_sym(L, *reg, sym);
 301     if (f == NULL)
 302       return ERRFUNC;  /* unable to find function */
 303     lua_pushcfunction(L, f);
 304     return 0;  /* return function */
 305   }
 306 }
 307
 308
 309 static int ll_loadlib (lua_State *L) {
 310   const char *path = luaL_checkstring(L, 1);
 311   const char *init = luaL_checkstring(L, 2);
 312   int stat = ll_loadfunc(L, path, init);
 313   if (stat == 0)  /* no errors? */
 314     return 1;  /* return the loaded function */
 315   else {  /* error; error message is on stack top */
 316     lua_pushnil(L);
 317     lua_insert(L, -2);
 318     lua_pushstring(L, (stat == ERRLIB) ?  LIB_FAIL : "init");
 319     return 3;  /* return nil, error message, and where */
 320   }
 321 }
 322
 323
 324
 325 /*
 326 ** {======================================================
 327 ** 'require' function
 328 ** =======================================================
 329 */
 330
 331
 332 static int readable (const char *filename) {
 333   FILE *f = fopen(filename, "r");  /* try to open file */
 334   if (f == NULL) return 0;  /* open failed */
 335   fclose(f);
 336   return 1;
 337 }
 338
 339
 340 static const char *pushnexttemplate (lua_State *L, const char *path) {
 341   const char *l;
 342   while (*path == *LUA_PATHSEP) path++;  /* skip separators */
 343   if (*path == '\0') return NULL;  /* no more templates */
 344   l = strchr(path, *LUA_PATHSEP);  /* find next separator */
 345   if (l == NULL) l = path + strlen(path);
 346   lua_pushlstring(L, path, l - path);  /* template */
 347   return l;
 348 }
 349
 350
 351 static const char *findfile (lua_State *L, const char *name,
 352                                            const char *pname) {
 353   const char *path;
 354   name = luaL_gsub(L, name, ".", LUA_DIRSEP);
 355   lua_getfield(L, LUA_ENVIRONINDEX, pname);
 356   path = lua_tostring(L, -1);
 357   if (path == NULL)
 358     luaL_error(L, LUA_QL("package.%s") " must be a string", pname);
 359   lua_pushliteral(L, "");  /* error accumulator */
 360   while ((path = pushnexttemplate(L, path)) != NULL) {
 361     const char *filename;
 362     filename = luaL_gsub(L, lua_tostring(L, -1), LUA_PATH_MARK, name);
 363     lua_remove(L, -2);  /* remove path template */
 364     if (readable(filename))  /* does file exist and is readable? */
 365       return filename;  /* return that file name */
 366     lua_pushfstring(L, "\n\tno file " LUA_QS, filename);
 367     lua_remove(L, -2);  /* remove file name */
 368     lua_concat(L, 2);  /* add entry to possible error message */
 369   }
 370   return NULL;  /* not found */
 371 }
 372
 373
 374 static void loaderror (lua_State *L, const char *filename) {
 375   luaL_error(L, "error loading module " LUA_QS " from file " LUA_QS ":\n\t%s",
 376                 lua_tostring(L, 1), filename, lua_tostring(L, -1));
 377 }
 378
 379
 380 static int loader_Lua (lua_State *L) {
 381   const char *filename;
 382   const char *name = luaL_checkstring(L, 1);
 383   filename = findfile(L, name, "path");
 384   if (filename == NULL) return 1;  /* library not found in this path */
 385   if (luaL_loadfile(L, filename) != 0)
 386     loaderror(L, filename);
 387   return 1;  /* library loaded successfully */
 388 }
 389
 390
 391 static const char *mkfuncname (lua_State *L, const char *modname) {
 392   const char *funcname;
 393   const char *mark = strchr(modname, *LUA_IGMARK);
 394   if (mark) modname = mark + 1;
 395   funcname = luaL_gsub(L, modname, ".", LUA_OFSEP);
 396   funcname = lua_pushfstring(L, POF"%s", funcname);
 397   lua_remove(L, -2);  /* remove 'gsub' result */
 398   return funcname;
 399 }
 400
 401
 402 static int loader_C (lua_State *L) {
 403   const char *funcname;
 404   const char *name = luaL_checkstring(L, 1);
 405   const char *filename = findfile(L, name, "cpath");
 406   if (filename == NULL) return 1;  /* library not found in this path */
 407   funcname = mkfuncname(L, name);
 408   if (ll_loadfunc(L, filename, funcname) != 0)
 409     loaderror(L, filename);
 410   return 1;  /* library loaded successfully */
 411 }
 412
 413
 414 static int loader_Croot (lua_State *L) {
 415   const char *funcname;
 416   const char *filename;
 417   const char *name = luaL_checkstring(L, 1);
 418   const char *p = strchr(name, '.');
 419   int stat;
 420   if (p == NULL) return 0;  /* is root */
 421   lua_pushlstring(L, name, p - name);
 422   filename = findfile(L, lua_tostring(L, -1), "cpath");
 423   if (filename == NULL) return 1;  /* root not found */
 424   funcname = mkfuncname(L, name);
 425   if ((stat = ll_loadfunc(L, filename, funcname)) != 0) {
 426     if (stat != ERRFUNC) loaderror(L, filename);  /* real error */
 427     lua_pushfstring(L, "\n\tno module " LUA_QS " in file " LUA_QS,
 428                        name, filename);
 429     return 1;  /* function not found */
 430   }
 431   return 1;
 432 }
 433
 434
 435 static int loader_preload (lua_State *L) {
 436   const char *name = luaL_checkstring(L, 1);
 437   lua_getfield(L, LUA_ENVIRONINDEX, "preload");
 438   if (!lua_istable(L, -1))
 439     luaL_error(L, LUA_QL("package.preload") " must be a table");
 440   lua_getfield(L, -1, name);
 441   if (lua_isnil(L, -1))  /* not found? */
 442     lua_pushfstring(L, "\n\tno field package.preload['%s']", name);
 443   return 1;
 444 }
 445
 446
 447 static const int sentinel_ = 0;
 448 #define sentinel        ((void *)&sentinel_)
 449
 450
 451 static int ll_require (lua_State *L) {
 452   const char *name = luaL_checkstring(L, 1);
 453   int i;
 454   lua_settop(L, 1);  /* _LOADED table will be at index 2 */
 455   lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
 456   lua_getfield(L, 2, name);
 457   if (lua_toboolean(L, -1)) {  /* is it there? */
 458     if (lua_touserdata(L, -1) == sentinel)  /* check loops */
 459       luaL_error(L, "loop or previous error loading module " LUA_QS, name);
 460     return 1;  /* package is already loaded */
 461   }
 462   /* else must load it; iterate over available loaders */
 463   lua_getfield(L, LUA_ENVIRONINDEX, "loaders");
 464   if (!lua_istable(L, -1))
 465     luaL_error(L, LUA_QL("package.loaders") " must be a table");
 466   lua_pushliteral(L, "");  /* error message accumulator */
 467   for (i=1; ; i++) {
 468     lua_rawgeti(L, -2, i);  /* get a loader */
 469     if (lua_isnil(L, -1))
 470       luaL_error(L, "module " LUA_QS " not found:%s",
 471                     name, lua_tostring(L, -2));
 472     lua_pushstring(L, name);
 473     lua_call(L, 1, 1);  /* call it */
 474     if (lua_isfunction(L, -1))  /* did it find module? */
 475       break;  /* module loaded successfully */
 476     else if (lua_isstring(L, -1))  /* loader returned error message? */
 477       lua_concat(L, 2);  /* accumulate it */
 478     else
 479       lua_pop(L, 1);
 480   }
 481   lua_pushlightuserdata(L, sentinel);
 482   lua_setfield(L, 2, name);  /* _LOADED[name] = sentinel */
 483   lua_pushstring(L, name);  /* pass name as argument to module */
 484   lua_call(L, 1, 1);  /* run loaded module */
 485   if (!lua_isnil(L, -1))  /* non-nil return? */
 486     lua_setfield(L, 2, name);  /* _LOADED[name] = returned value */
 487   lua_getfield(L, 2, name);
 488   if (lua_touserdata(L, -1) == sentinel) {   /* module did not set a value? */
 489     lua_pushboolean(L, 1);  /* use true as result */
 490     lua_pushvalue(L, -1);  /* extra copy to be returned */
 491     lua_setfield(L, 2, name);  /* _LOADED[name] = true */
 492   }
 493   return 1;
 494 }
 495
 496 /* }====================================================== */
 497
 498
 499
 500 /*
 501 ** {======================================================
 502 ** 'module' function
 503 ** =======================================================
 504 */
 505
 506
 507 static void setfenv (lua_State *L) {
 508   lua_Debug ar;
 509   lua_getstack(L, 1, &ar);
 510   lua_getinfo(L, "f", &ar);
 511   lua_pushvalue(L, -2);
 512   lua_setfenv(L, -2);
 513   lua_pop(L, 1);
 514 }
 515
 516
 517 static void dooptions (lua_State *L, int n) {
 518   int i;
 519   for (i = 2; i <= n; i++) {
 520     lua_pushvalue(L, i);  /* get option (a function) */
 521     lua_pushvalue(L, -2);  /* module */
 522     lua_call(L, 1, 0);
 523   }
 524 }
 525
 526
 527 static void modinit (lua_State *L, const char *modname) {
 528   const char *dot;
 529   lua_pushvalue(L, -1);
 530   lua_setfield(L, -2, "_M");  /* module._M = module */
 531   lua_pushstring(L, modname);
 532   lua_setfield(L, -2, "_NAME");
 533   dot = strrchr(modname, '.');  /* look for last dot in module name */
 534   if (dot == NULL) dot = modname;
 535   else dot++;
 536   /* set _PACKAGE as package name (full module name minus last part) */
 537   lua_pushlstring(L, modname, dot - modname);
 538   lua_setfield(L, -2, "_PACKAGE");
 539 }
 540
 541
 542 static int ll_module (lua_State *L) {
 543   const char *modname = luaL_checkstring(L, 1);
 544   int loaded = lua_gettop(L) + 1;  /* index of _LOADED table */
 545   lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
 546   lua_getfield(L, loaded, modname);  /* get _LOADED[modname] */
 547   if (!lua_istable(L, -1)) {  /* not found? */
 548     lua_pop(L, 1);  /* remove previous result */
 549     /* try global variable (and create one if it does not exist) */
 550     if (luaL_findtable(L, LUA_GLOBALSINDEX, modname, 1) != NULL)
 551       return luaL_error(L, "name conflict for module " LUA_QS, modname);
 552     lua_pushvalue(L, -1);
 553     lua_setfield(L, loaded, modname);  /* _LOADED[modname] = new table */
 554   }
 555   /* check whether table already has a _NAME field */
 556   lua_getfield(L, -1, "_NAME");
 557   if (!lua_isnil(L, -1))  /* is table an initialized module? */
 558     lua_pop(L, 1);
 559   else {  /* no; initialize it */
 560     lua_pop(L, 1);
 561     modinit(L, modname);
 562   }
 563   lua_pushvalue(L, -1);
 564   setfenv(L);
 565   dooptions(L, loaded - 1);
 566   return 0;
 567 }
 568
 569
 570 static int ll_seeall (lua_State *L) {
 571   luaL_checktype(L, 1, LUA_TTABLE);
 572   if (!lua_getmetatable(L, 1)) {
 573     lua_createtable(L, 0, 1); /* create new metatable */
 574     lua_pushvalue(L, -1);
 575     lua_setmetatable(L, 1);
 576   }
 577   lua_pushvalue(L, LUA_GLOBALSINDEX);
 578   lua_setfield(L, -2, "__index");  /* mt.__index = _G */
 579   return 0;
 580 }
 581
 582
 583 /* }====================================================== */
 584
 585
 586
 587 /* auxiliary mark (for internal use) */
 588 #define AUXMARK         "\1"
 589
 590 static void setpath (lua_State *L, const char *fieldname, const char *envname,
 591                                    const char *def) {
 592   const char *path = getenv(envname);
 593   if (path == NULL)  /* no environment variable? */
 594     lua_pushstring(L, def);  /* use default */
 595   else {
 596     /* replace ";;" by ";AUXMARK;" and then AUXMARK by default path */
 597     path = luaL_gsub(L, path, LUA_PATHSEP LUA_PATHSEP,
 598                               LUA_PATHSEP AUXMARK LUA_PATHSEP);
 599     luaL_gsub(L, path, AUXMARK, def);
 600     lua_remove(L, -2);
 601   }
 602   setprogdir(L);
 603   lua_setfield(L, -2, fieldname);
 604 }
 605
 606
 607 static const luaL_Reg pk_funcs[] = {
 608   {"loadlib", ll_loadlib},
 609   {"seeall", ll_seeall},
 610   {NULL, NULL}
 611 };
 612
 613
 614 static const luaL_Reg ll_funcs[] = {
 615   {"module", ll_module},
 616   {"require", ll_require},
 617   {NULL, NULL}
 618 };
 619
 620
 621 static const lua_CFunction loaders[] =
 622   {loader_preload, loader_Lua, loader_C, loader_Croot, NULL};
 623
 624
 625 LUALIB_API int luaopen_package (lua_State *L) {
 626   int i;
 627   /* create new type _LOADLIB */
 628   luaL_newmetatable(L, "_LOADLIB");
 629   lua_pushcfunction(L, gctm);
 630   lua_setfield(L, -2, "__gc");
 631   /* create `package' table */
 632   luaL_register(L, LUA_LOADLIBNAME, pk_funcs);
 633 #if defined(LUA_COMPAT_LOADLIB)
 634   lua_getfield(L, -1, "loadlib");
 635   lua_setfield(L, LUA_GLOBALSINDEX, "loadlib");
 636 #endif
 637   lua_pushvalue(L, -1);
 638   lua_replace(L, LUA_ENVIRONINDEX);
 639   /* create `loaders' table */
 640   lua_createtable(L, 0, sizeof(loaders)/sizeof(loaders[0]) - 1);
 641   /* fill it with pre-defined loaders */
 642   for (i=0; loaders[i] != NULL; i++) {
 643     lua_pushcfunction(L, loaders[i]);
 644     lua_rawseti(L, -2, i+1);
 645   }
 646   lua_setfield(L, -2, "loaders");  /* put it in field `loaders' */
 647   setpath(L, "path", LUA_PATH, LUA_PATH_DEFAULT);  /* set field `path' */
 648   setpath(L, "cpath", LUA_CPATH, LUA_CPATH_DEFAULT); /* set field `cpath' */
 649   /* store config information */
 650   lua_pushliteral(L, LUA_DIRSEP "\n" LUA_PATHSEP "\n" LUA_PATH_MARK "\n"
 651                      LUA_EXECDIR "\n" LUA_IGMARK);
 652   lua_setfield(L, -2, "config");
 653   /* set field `loaded' */
 654   luaL_findtable(L, LUA_REGISTRYINDEX, "_LOADED", 2);
 655   lua_setfield(L, -2, "loaded");
 656   /* set field `preload' */
 657   lua_newtable(L);
 658   lua_setfield(L, -2, "preload");
 659   lua_pushvalue(L, LUA_GLOBALSINDEX);
 660   luaL_register(L, NULL, ll_funcs);  /* open lib into global table */
 661   lua_pop(L, 1);
 662   return 1;  /* return 'package' table */
 663 }
 664