src/lib_package.c

   1 /*
   2 ** Package library.
   3 ** Copyright (C) 2005-2011 Mike Pall. See Copyright Notice in luajit.h
   4 **
   5 ** Major portions taken verbatim or adapted from the Lua interpreter.
   6 ** Copyright (C) 1994-2011 Lua.org, PUC-Rio. See Copyright Notice in lua.h
   7 */
   8
   9 #define lib_package_c
  10 #define LUA_LIB
  11
  12 #include "lua.h"
  13 #include "lauxlib.h"
  14 #include "lualib.h"
  15
  16 #include "lj_obj.h"
  17 #include "lj_err.h"
  18 #include "lj_lib.h"
  19
  20 /* ------------------------------------------------------------------------ */
  21
  22 /* Error codes for ll_loadfunc. */
  23 #define PACKAGE_ERR_LIB         1
  24 #define PACKAGE_ERR_FUNC        2
  25 #define PACKAGE_ERR_LOAD        3
  26
  27 /* Redefined in platform specific part. */
  28 #define PACKAGE_LIB_FAIL        "open"
  29 #define setprogdir(L)           ((void)0)
  30
  31 /* Symbol name prefixes. */
  32 #define SYMPREFIX_CF            "luaopen_%s"
  33 #define SYMPREFIX_BC            "luaJIT_BC_%s"
  34
  35 #if LJ_TARGET_DLOPEN
  36
  37 #include <dlfcn.h>
  38
  39 static void ll_unloadlib(void *lib)
  40 {
  41   dlclose(lib);
  42 }
  43
  44 static void *ll_load(lua_State *L, const char *path)
  45 {
  46   void *lib = dlopen(path, RTLD_NOW);
  47   if (lib == NULL) lua_pushstring(L, dlerror());
  48   return lib;
  49 }
  50
  51 static lua_CFunction ll_sym(lua_State *L, void *lib, const char *sym)
  52 {
  53   lua_CFunction f = (lua_CFunction)dlsym(lib, sym);
  54   if (f == NULL) lua_pushstring(L, dlerror());
  55   return f;
  56 }
  57
  58 static const char *ll_bcsym(void *lib, const char *sym)
  59 {
  60 #if defined(RTLD_DEFAULT)
  61   if (lib == NULL) lib = RTLD_DEFAULT;
  62 #elif LJ_TARGET_OSX || LJ_TARGET_BSD
  63   if (lib == NULL) lib = (void *)(intptr_t)-2;
  64 #endif
  65   return (const char *)dlsym(lib, sym);
  66 }
  67
  68 #elif LJ_TARGET_WINDOWS
  69
  70 #define WIN32_LEAN_AND_MEAN
  71 #ifndef WINVER
  72 #define WINVER 0x0500
  73 #endif
  74 #include <windows.h>
  75
  76 #ifndef GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS
  77 #define GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS  4
  78 BOOL WINAPI GetModuleHandleExA(DWORD, LPCSTR, HMODULE*);
  79 #endif
  80
  81 #undef setprogdir
  82
  83 static void setprogdir(lua_State *L)
  84 {
  85   char buff[MAX_PATH + 1];
  86   char *lb;
  87   DWORD nsize = sizeof(buff);
  88   DWORD n = GetModuleFileNameA(NULL, buff, nsize);
  89   if (n == 0 || n == nsize || (lb = strrchr(buff, '\\')) == NULL) {
  90     luaL_error(L, "unable to get ModuleFileName");
  91   } else {
  92     *lb = '\0';
  93     luaL_gsub(L, lua_tostring(L, -1), LUA_EXECDIR, buff);
  94     lua_remove(L, -2);  /* remove original string */
  95   }
  96 }
  97
  98 static void pusherror(lua_State *L)
  99 {
 100   DWORD error = GetLastError();
 101   char buffer[128];
 102   if (FormatMessageA(FORMAT_MESSAGE_IGNORE_INSERTS | FORMAT_MESSAGE_FROM_SYSTEM,
 103       NULL, error, 0, buffer, sizeof(buffer), NULL))
 104     lua_pushstring(L, buffer);
 105   else
 106     lua_pushfstring(L, "system error %d\n", error);
 107 }
 108
 109 static void ll_unloadlib(void *lib)
 110 {
 111   FreeLibrary((HINSTANCE)lib);
 112 }
 113
 114 static void *ll_load(lua_State *L, const char *path)
 115 {
 116   HINSTANCE lib = LoadLibraryA(path);
 117   if (lib == NULL) pusherror(L);
 118   return lib;
 119 }
 120
 121 static lua_CFunction ll_sym(lua_State *L, void *lib, const char *sym)
 122 {
 123   lua_CFunction f = (lua_CFunction)GetProcAddress((HINSTANCE)lib, sym);
 124   if (f == NULL) pusherror(L);
 125   return f;
 126 }
 127
 128 static const char *ll_bcsym(void *lib, const char *sym)
 129 {
 130   if (lib) {
 131     return (const char *)GetProcAddress((HINSTANCE)lib, sym);
 132   } else {
 133     HINSTANCE h = GetModuleHandleA(NULL);
 134     const char *p = (const char *)GetProcAddress(h, sym);
 135     if (p == NULL && GetModuleHandleExA(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS,
 136                                         (const char *)ll_bcsym, &h))
 137       p = (const char *)GetProcAddress(h, sym);
 138     return p;
 139   }
 140 }
 141
 142 #else
 143
 144 #undef PACKAGE_LIB_FAIL
 145 #define PACKAGE_LIB_FAIL        "absent"
 146
 147 #define DLMSG   "dynamic libraries not enabled; no support for target OS"
 148
 149 static void ll_unloadlib(void *lib)
 150 {
 151   (void)lib;
 152 }
 153
 154 static void *ll_load(lua_State *L, const char *path)
 155 {
 156   (void)path;
 157   lua_pushliteral(L, DLMSG);
 158   return NULL;
 159 }
 160
 161 static lua_CFunction ll_sym(lua_State *L, void *lib, const char *sym)
 162 {
 163   (void)lib; (void)sym;
 164   lua_pushliteral(L, DLMSG);
 165   return NULL;
 166 }
 167
 168 static const char *ll_bcsym(void *lib, const char *sym)
 169 {
 170   (void)lib; (void)sym;
 171   return NULL;
 172 }
 173
 174 #endif
 175
 176 /* ------------------------------------------------------------------------ */
 177
 178 static void **ll_register(lua_State *L, const char *path)
 179 {
 180   void **plib;
 181   lua_pushfstring(L, "LOADLIB: %s", path);
 182   lua_gettable(L, LUA_REGISTRYINDEX);  /* check library in registry? */
 183   if (!lua_isnil(L, -1)) {  /* is there an entry? */
 184     plib = (void **)lua_touserdata(L, -1);
 185   } else {  /* no entry yet; create one */
 186     lua_pop(L, 1);
 187     plib = (void **)lua_newuserdata(L, sizeof(void *));
 188     *plib = NULL;
 189     luaL_getmetatable(L, "_LOADLIB");
 190     lua_setmetatable(L, -2);
 191     lua_pushfstring(L, "LOADLIB: %s", path);
 192     lua_pushvalue(L, -2);
 193     lua_settable(L, LUA_REGISTRYINDEX);
 194   }
 195   return plib;
 196 }
 197
 198 static const char *mksymname(lua_State *L, const char *modname,
 199                              const char *prefix)
 200 {
 201   const char *funcname;
 202   const char *mark = strchr(modname, *LUA_IGMARK);
 203   if (mark) modname = mark + 1;
 204   funcname = luaL_gsub(L, modname, ".", "_");
 205   funcname = lua_pushfstring(L, prefix, funcname);
 206   lua_remove(L, -2);  /* remove 'gsub' result */
 207   return funcname;
 208 }
 209
 210 static int ll_loadfunc(lua_State *L, const char *path, const char *name, int r)
 211 {
 212   void **reg = ll_register(L, path);
 213   if (*reg == NULL) *reg = ll_load(L, path);
 214   if (*reg == NULL) {
 215     return PACKAGE_ERR_LIB;  /* unable to load library */
 216   } else {
 217     const char *sym = r ? name : mksymname(L, name, SYMPREFIX_CF);
 218     lua_CFunction f = ll_sym(L, *reg, sym);
 219     if (f) {
 220       lua_pushcfunction(L, f);
 221       return 0;
 222     }
 223     if (!r) {
 224       const char *bcdata = ll_bcsym(*reg, mksymname(L, name, SYMPREFIX_BC));
 225       lua_pop(L, 1);
 226       if (bcdata) {
 227         if (luaL_loadbuffer(L, bcdata, ~(size_t)0, name) != 0)
 228           return PACKAGE_ERR_LOAD;
 229         return 0;
 230       }
 231     }
 232     return PACKAGE_ERR_FUNC;  /* unable to find function */
 233   }
 234 }
 235
 236 static int lj_cf_package_loadlib(lua_State *L)
 237 {
 238   const char *path = luaL_checkstring(L, 1);
 239   const char *init = luaL_checkstring(L, 2);
 240   int st = ll_loadfunc(L, path, init, 1);
 241   if (st == 0) {  /* no errors? */
 242     return 1;  /* return the loaded function */
 243   } else {  /* error; error message is on stack top */
 244     lua_pushnil(L);
 245     lua_insert(L, -2);
 246     lua_pushstring(L, (st == PACKAGE_ERR_LIB) ?  PACKAGE_LIB_FAIL : "init");
 247     return 3;  /* return nil, error message, and where */
 248   }
 249 }
 250
 251 static int lj_cf_package_unloadlib(lua_State *L)
 252 {
 253   void **lib = (void **)luaL_checkudata(L, 1, "_LOADLIB");
 254   if (*lib) ll_unloadlib(*lib);
 255   *lib = NULL;  /* mark library as closed */
 256   return 0;
 257 }
 258
 259 /* ------------------------------------------------------------------------ */
 260
 261 static int readable(const char *filename)
 262 {
 263   FILE *f = fopen(filename, "r");  /* try to open file */
 264   if (f == NULL) return 0;  /* open failed */
 265   fclose(f);
 266   return 1;
 267 }
 268
 269 static const char *pushnexttemplate(lua_State *L, const char *path)
 270 {
 271   const char *l;
 272   while (*path == *LUA_PATHSEP) path++;  /* skip separators */
 273   if (*path == '\0') return NULL;  /* no more templates */
 274   l = strchr(path, *LUA_PATHSEP);  /* find next separator */
 275   if (l == NULL) l = path + strlen(path);
 276   lua_pushlstring(L, path, (size_t)(l - path));  /* template */
 277   return l;
 278 }
 279
 280 static const char *searchpath (lua_State *L, const char *name,
 281                                const char *path)
 282 {
 283   name = luaL_gsub(L, name, ".", LUA_DIRSEP);
 284   lua_pushliteral(L, "");  /* error accumulator */
 285   while ((path = pushnexttemplate(L, path)) != NULL) {
 286     const char *filename = luaL_gsub(L, lua_tostring(L, -1),
 287                                      LUA_PATH_MARK, name);
 288     lua_remove(L, -2);  /* remove path template */
 289     if (readable(filename))  /* does file exist and is readable? */
 290       return filename;  /* return that file name */
 291     lua_pushfstring(L, "\n\tno file " LUA_QS, filename);
 292     lua_remove(L, -2);  /* remove file name */
 293     lua_concat(L, 2);  /* add entry to possible error message */
 294   }
 295   return NULL;  /* not found */
 296 }
 297
 298 static int lj_cf_package_searchpath(lua_State *L)
 299 {
 300   const char *f = searchpath(L, luaL_checkstring(L, 1), luaL_checkstring(L, 2));
 301   if (f != NULL) {
 302     return 1;
 303   } else {  /* error message is on top of the stack */
 304     lua_pushnil(L);
 305     lua_insert(L, -2);
 306     return 2;  /* return nil + error message */
 307   }
 308 }
 309
 310 static const char *findfile(lua_State *L, const char *name,
 311                             const char *pname)
 312 {
 313   const char *path;
 314   lua_getfield(L, LUA_ENVIRONINDEX, pname);
 315   path = lua_tostring(L, -1);
 316   if (path == NULL)
 317     luaL_error(L, LUA_QL("package.%s") " must be a string", pname);
 318   return searchpath(L, name, path);
 319 }
 320
 321 static void loaderror(lua_State *L, const char *filename)
 322 {
 323   luaL_error(L, "error loading module " LUA_QS " from file " LUA_QS ":\n\t%s",
 324              lua_tostring(L, 1), filename, lua_tostring(L, -1));
 325 }
 326
 327 static int lj_cf_package_loader_lua(lua_State *L)
 328 {
 329   const char *filename;
 330   const char *name = luaL_checkstring(L, 1);
 331   filename = findfile(L, name, "path");
 332   if (filename == NULL) return 1;  /* library not found in this path */
 333   if (luaL_loadfile(L, filename) != 0)
 334     loaderror(L, filename);
 335   return 1;  /* library loaded successfully */
 336 }
 337
 338 static int lj_cf_package_loader_c(lua_State *L)
 339 {
 340   const char *name = luaL_checkstring(L, 1);
 341   const char *filename = findfile(L, name, "cpath");
 342   if (filename == NULL) return 1;  /* library not found in this path */
 343   if (ll_loadfunc(L, filename, name, 0) != 0)
 344     loaderror(L, filename);
 345   return 1;  /* library loaded successfully */
 346 }
 347
 348 static int lj_cf_package_loader_croot(lua_State *L)
 349 {
 350   const char *filename;
 351   const char *name = luaL_checkstring(L, 1);
 352   const char *p = strchr(name, '.');
 353   int st;
 354   if (p == NULL) return 0;  /* is root */
 355   lua_pushlstring(L, name, (size_t)(p - name));
 356   filename = findfile(L, lua_tostring(L, -1), "cpath");
 357   if (filename == NULL) return 1;  /* root not found */
 358   if ((st = ll_loadfunc(L, filename, name, 0)) != 0) {
 359     if (st != PACKAGE_ERR_FUNC) loaderror(L, filename);  /* real error */
 360     lua_pushfstring(L, "\n\tno module " LUA_QS " in file " LUA_QS,
 361                     name, filename);
 362     return 1;  /* function not found */
 363   }
 364   return 1;
 365 }
 366
 367 static int lj_cf_package_loader_preload(lua_State *L)
 368 {
 369   const char *name = luaL_checkstring(L, 1);
 370   lua_getfield(L, LUA_ENVIRONINDEX, "preload");
 371   if (!lua_istable(L, -1))
 372     luaL_error(L, LUA_QL("package.preload") " must be a table");
 373   lua_getfield(L, -1, name);
 374   if (lua_isnil(L, -1)) {  /* Not found? */
 375     const char *bcname = mksymname(L, name, SYMPREFIX_BC);
 376     const char *bcdata = ll_bcsym(NULL, bcname);
 377     if (bcdata == NULL || luaL_loadbuffer(L, bcdata, ~(size_t)0, name) != 0)
 378       lua_pushfstring(L, "\n\tno field package.preload['%s']", name);
 379   }
 380   return 1;
 381 }
 382
 383 /* ------------------------------------------------------------------------ */
 384
 385 static const int sentinel_ = 0;
 386 #define sentinel        ((void *)&sentinel_)
 387
 388 static int lj_cf_package_require(lua_State *L)
 389 {
 390   const char *name = luaL_checkstring(L, 1);
 391   int i;
 392   lua_settop(L, 1);  /* _LOADED table will be at index 2 */
 393   lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
 394   lua_getfield(L, 2, name);
 395   if (lua_toboolean(L, -1)) {  /* is it there? */
 396     if (lua_touserdata(L, -1) == sentinel)  /* check loops */
 397       luaL_error(L, "loop or previous error loading module " LUA_QS, name);
 398     return 1;  /* package is already loaded */
 399   }
 400   /* else must load it; iterate over available loaders */
 401   lua_getfield(L, LUA_ENVIRONINDEX, "loaders");
 402   if (!lua_istable(L, -1))
 403     luaL_error(L, LUA_QL("package.loaders") " must be a table");
 404   lua_pushliteral(L, "");  /* error message accumulator */
 405   for (i = 1; ; i++) {
 406     lua_rawgeti(L, -2, i);  /* get a loader */
 407     if (lua_isnil(L, -1))
 408       luaL_error(L, "module " LUA_QS " not found:%s",
 409                  name, lua_tostring(L, -2));
 410     lua_pushstring(L, name);
 411     lua_call(L, 1, 1);  /* call it */
 412     if (lua_isfunction(L, -1))  /* did it find module? */
 413       break;  /* module loaded successfully */
 414     else if (lua_isstring(L, -1))  /* loader returned error message? */
 415       lua_concat(L, 2);  /* accumulate it */
 416     else
 417       lua_pop(L, 1);
 418   }
 419   lua_pushlightuserdata(L, sentinel);
 420   lua_setfield(L, 2, name);  /* _LOADED[name] = sentinel */
 421   lua_pushstring(L, name);  /* pass name as argument to module */
 422   lua_call(L, 1, 1);  /* run loaded module */
 423   if (!lua_isnil(L, -1))  /* non-nil return? */
 424     lua_setfield(L, 2, name);  /* _LOADED[name] = returned value */
 425   lua_getfield(L, 2, name);
 426   if (lua_touserdata(L, -1) == sentinel) {   /* module did not set a value? */
 427     lua_pushboolean(L, 1);  /* use true as result */
 428     lua_pushvalue(L, -1);  /* extra copy to be returned */
 429     lua_setfield(L, 2, name);  /* _LOADED[name] = true */
 430   }
 431   lj_lib_checkfpu(L);
 432   return 1;
 433 }
 434
 435 /* ------------------------------------------------------------------------ */
 436
 437 static void setfenv(lua_State *L)
 438 {
 439   lua_Debug ar;
 440   if (lua_getstack(L, 1, &ar) == 0 ||
 441       lua_getinfo(L, "f", &ar) == 0 ||  /* get calling function */
 442       lua_iscfunction(L, -1))
 443     luaL_error(L, LUA_QL("module") " not called from a Lua function");
 444   lua_pushvalue(L, -2);
 445   lua_setfenv(L, -2);
 446   lua_pop(L, 1);
 447 }
 448
 449 static void dooptions(lua_State *L, int n)
 450 {
 451   int i;
 452   for (i = 2; i <= n; i++) {
 453     lua_pushvalue(L, i);  /* get option (a function) */
 454     lua_pushvalue(L, -2);  /* module */
 455     lua_call(L, 1, 0);
 456   }
 457 }
 458
 459 static void modinit(lua_State *L, const char *modname)
 460 {
 461   const char *dot;
 462   lua_pushvalue(L, -1);
 463   lua_setfield(L, -2, "_M");  /* module._M = module */
 464   lua_pushstring(L, modname);
 465   lua_setfield(L, -2, "_NAME");
 466   dot = strrchr(modname, '.');  /* look for last dot in module name */
 467   if (dot == NULL) dot = modname; else dot++;
 468   /* set _PACKAGE as package name (full module name minus last part) */
 469   lua_pushlstring(L, modname, (size_t)(dot - modname));
 470   lua_setfield(L, -2, "_PACKAGE");
 471 }
 472
 473 static int lj_cf_package_module(lua_State *L)
 474 {
 475   const char *modname = luaL_checkstring(L, 1);
 476   int loaded = lua_gettop(L) + 1;  /* index of _LOADED table */
 477   lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
 478   lua_getfield(L, loaded, modname);  /* get _LOADED[modname] */
 479   if (!lua_istable(L, -1)) {  /* not found? */
 480     lua_pop(L, 1);  /* remove previous result */
 481     /* try global variable (and create one if it does not exist) */
 482     if (luaL_findtable(L, LUA_GLOBALSINDEX, modname, 1) != NULL)
 483       lj_err_callerv(L, LJ_ERR_BADMODN, modname);
 484     lua_pushvalue(L, -1);
 485     lua_setfield(L, loaded, modname);  /* _LOADED[modname] = new table */
 486   }
 487   /* check whether table already has a _NAME field */
 488   lua_getfield(L, -1, "_NAME");
 489   if (!lua_isnil(L, -1)) {  /* is table an initialized module? */
 490     lua_pop(L, 1);
 491   } else {  /* no; initialize it */
 492     lua_pop(L, 1);
 493     modinit(L, modname);
 494   }
 495   lua_pushvalue(L, -1);
 496   setfenv(L);
 497   dooptions(L, loaded - 1);
 498   return 0;
 499 }
 500
 501 static int lj_cf_package_seeall(lua_State *L)
 502 {
 503   luaL_checktype(L, 1, LUA_TTABLE);
 504   if (!lua_getmetatable(L, 1)) {
 505     lua_createtable(L, 0, 1); /* create new metatable */
 506     lua_pushvalue(L, -1);
 507     lua_setmetatable(L, 1);
 508   }
 509   lua_pushvalue(L, LUA_GLOBALSINDEX);
 510   lua_setfield(L, -2, "__index");  /* mt.__index = _G */
 511   return 0;
 512 }
 513
 514 /* ------------------------------------------------------------------------ */
 515
 516 #define AUXMARK         "\1"
 517
 518 static void setpath(lua_State *L, const char *fieldname, const char *envname,
 519                     const char *def)
 520 {
 521   const char *path = getenv(envname);
 522   if (path == NULL) {
 523     lua_pushstring(L, def);
 524   } else {
 525     path = luaL_gsub(L, path, LUA_PATHSEP LUA_PATHSEP,
 526                               LUA_PATHSEP AUXMARK LUA_PATHSEP);
 527     luaL_gsub(L, path, AUXMARK, def);
 528     lua_remove(L, -2);
 529   }
 530   setprogdir(L);
 531   lua_setfield(L, -2, fieldname);
 532 }
 533
 534 static const luaL_Reg package_lib[] = {
 535   { "loadlib",  lj_cf_package_loadlib },
 536   { "searchpath",  lj_cf_package_searchpath },
 537   { "seeall",   lj_cf_package_seeall },
 538   { NULL, NULL }
 539 };
 540
 541 static const luaL_Reg package_global[] = {
 542   { "module",   lj_cf_package_module },
 543   { "require",  lj_cf_package_require },
 544   { NULL, NULL }
 545 };
 546
 547 static const lua_CFunction package_loaders[] =
 548 {
 549   lj_cf_package_loader_preload,
 550   lj_cf_package_loader_lua,
 551   lj_cf_package_loader_c,
 552   lj_cf_package_loader_croot,
 553   NULL
 554 };
 555
 556 LUALIB_API int luaopen_package(lua_State *L)
 557 {
 558   int i;
 559   luaL_newmetatable(L, "_LOADLIB");
 560   lj_lib_pushcf(L, lj_cf_package_unloadlib, 1);
 561   lua_setfield(L, -2, "__gc");
 562   luaL_register(L, LUA_LOADLIBNAME, package_lib);
 563   lua_pushvalue(L, -1);
 564   lua_replace(L, LUA_ENVIRONINDEX);
 565   lua_createtable(L, sizeof(package_loaders)/sizeof(package_loaders[0])-1, 0);
 566   for (i = 0; package_loaders[i] != NULL; i++) {
 567     lj_lib_pushcf(L, package_loaders[i], 1);
 568     lua_rawseti(L, -2, i+1);
 569   }
 570   lua_setfield(L, -2, "loaders");
 571   setpath(L, "path", LUA_PATH, LUA_PATH_DEFAULT);
 572   setpath(L, "cpath", LUA_CPATH, LUA_CPATH_DEFAULT);
 573   lua_pushliteral(L, LUA_PATH_CONFIG);
 574   lua_setfield(L, -2, "config");
 575   luaL_findtable(L, LUA_REGISTRYINDEX, "_LOADED", 16);
 576   lua_setfield(L, -2, "loaded");
 577   luaL_findtable(L, LUA_REGISTRYINDEX, "_PRELOAD", 4);
 578   lua_setfield(L, -2, "preload");
 579   lua_pushvalue(L, LUA_GLOBALSINDEX);
 580   luaL_register(L, NULL, package_global);
 581   lua_pop(L, 1);
 582   return 1;
 583 }
 584