1/*
2** $Id: loadlib.c,v 1.130.1.1 2017/04/19 17:20:42 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 Windows, and a stub for other
8** systems.
9*/
10
11#define loadlib_c
12#define LUA_LIB
13
14#include "lprefix.h"
15
16
17#include <stdio.h>
18#include <stdlib.h>
19#include <string.h>
20
21#include "lua.h"
22
23#include "lauxlib.h"
24#include "lualib.h"
25
26
27/*
28** LUA_IGMARK is a mark to ignore all before it when building the
29** luaopen_ function name.
30*/
31#if !defined (LUA_IGMARK)
32#define LUA_IGMARK "-"
33#endif
34
35
36/*
37** LUA_CSUBSEP is the character that replaces dots in submodule names
38** when searching for a C loader.
39** LUA_LSUBSEP is the character that replaces dots in submodule names
40** when searching for a Lua loader.
41*/
42#if !defined(LUA_CSUBSEP)
43#define LUA_CSUBSEP LUA_DIRSEP
44#endif
45
46#if !defined(LUA_LSUBSEP)
47#define LUA_LSUBSEP LUA_DIRSEP
48#endif
49
50
51/* prefix for open functions in C libraries */
52#define LUA_POF "luaopen_"
53
54/* separator for open functions in C libraries */
55#define LUA_OFSEP "_"
56
57
58/*
59** unique key for table in the registry that keeps handles
60** for all loaded C libraries
61*/
62static const int CLIBS = 0;
63
64#define LIB_FAIL "open"
65
66
67#define setprogdir(L) ((void)0)
68
69
70/*
71** system-dependent functions
72*/
73
74/*
75** unload library 'lib'
76*/
77static void lsys_unloadlib (void *lib);
78
79/*
80** load C library in file 'path'. If 'seeglb', load with all names in
81** the library global.
82** Returns the library; in case of error, returns NULL plus an
83** error string in the stack.
84*/
85static void *lsys_load (lua_State *L, const char *path, int seeglb);
86
87/*
88** Try to find a function named 'sym' in library 'lib'.
89** Returns the function; in case of error, returns NULL plus an
90** error string in the stack.
91*/
92static lua_CFunction lsys_sym (lua_State *L, void *lib, const char *sym);
93
94
95
96
97#if defined(LUA_USE_DLOPEN) /* { */
98/*
99** {========================================================================
100** This is an implementation of loadlib based on the dlfcn interface.
101** The dlfcn interface is available in Linux, SunOS, Solaris, IRIX, FreeBSD,
102** NetBSD, AIX 4.2, HPUX 11, and probably most other Unix flavors, at least
103** as an emulation layer on top of native functions.
104** =========================================================================
105*/
106
107#include <dlfcn.h>
108
109/*
110** Macro to convert pointer-to-void* to pointer-to-function. This cast
111** is undefined according to ISO C, but POSIX assumes that it works.
112** (The '__extension__' in gnu compilers is only to avoid warnings.)
113*/
114#if defined(__GNUC__)
115#define cast_func(p) (__extension__ (lua_CFunction)(p))
116#else
117#define cast_func(p) ((lua_CFunction)(p))
118#endif
119
120
121static void lsys_unloadlib (void *lib) {
122 dlclose(lib);
123}
124
125
126static void *lsys_load (lua_State *L, const char *path, int seeglb) {
127 void *lib = dlopen(path, RTLD_NOW | (seeglb ? RTLD_GLOBAL : RTLD_LOCAL));
128 if (lib == NULL) lua_pushstring(L, dlerror());
129 return lib;
130}
131
132
133static lua_CFunction lsys_sym (lua_State *L, void *lib, const char *sym) {
134 lua_CFunction f = cast_func(dlsym(lib, sym));
135 if (f == NULL) lua_pushstring(L, dlerror());
136 return f;
137}
138
139/* }====================================================== */
140
141
142
143#elif defined(LUA_DL_DLL) /* }{ */
144/*
145** {======================================================================
146** This is an implementation of loadlib for Windows using native functions.
147** =======================================================================
148*/
149
150#include <windows.h>
151
152
153/*
154** optional flags for LoadLibraryEx
155*/
156#if !defined(LUA_LLE_FLAGS)
157#define LUA_LLE_FLAGS 0
158#endif
159
160
161#undef setprogdir
162
163
164/*
165** Replace in the path (on the top of the stack) any occurrence
166** of LUA_EXEC_DIR with the executable's path.
167*/
168static void setprogdir (lua_State *L) {
169 char buff[MAX_PATH + 1];
170 char *lb;
171 DWORD nsize = sizeof(buff)/sizeof(char);
172 DWORD n = GetModuleFileNameA(NULL, buff, nsize); /* get exec. name */
173 if (n == 0 || n == nsize || (lb = strrchr(buff, '\\')) == NULL)
174 luaL_error(L, "unable to get ModuleFileName");
175 else {
176 *lb = '\0'; /* cut name on the last '\\' to get the path */
177 luaL_gsub(L, lua_tostring(L, -1), LUA_EXEC_DIR, buff);
178 lua_remove(L, -2); /* remove original string */
179 }
180}
181
182
183
184
185static void pusherror (lua_State *L) {
186 int error = GetLastError();
187 char buffer[128];
188 if (FormatMessageA(FORMAT_MESSAGE_IGNORE_INSERTS | FORMAT_MESSAGE_FROM_SYSTEM,
189 NULL, error, 0, buffer, sizeof(buffer)/sizeof(char), NULL))
190 lua_pushstring(L, buffer);
191 else
192 lua_pushfstring(L, "system error %d\n", error);
193}
194
195static void lsys_unloadlib (void *lib) {
196 FreeLibrary((HMODULE)lib);
197}
198
199
200static void *lsys_load (lua_State *L, const char *path, int seeglb) {
201 HMODULE lib = LoadLibraryExA(path, NULL, LUA_LLE_FLAGS);
202 (void)(seeglb); /* not used: symbols are 'global' by default */
203 if (lib == NULL) pusherror(L);
204 return lib;
205}
206
207
208static lua_CFunction lsys_sym (lua_State *L, void *lib, const char *sym) {
209 lua_CFunction f = (lua_CFunction)GetProcAddress((HMODULE)lib, sym);
210 if (f == NULL) pusherror(L);
211 return f;
212}
213
214/* }====================================================== */
215
216
217#else /* }{ */
218/*
219** {======================================================
220** Fallback for other systems
221** =======================================================
222*/
223
224#undef LIB_FAIL
225#define LIB_FAIL "absent"
226
227
228#define DLMSG "dynamic libraries not enabled; check your Lua installation"
229
230
231static void lsys_unloadlib (void *lib) {
232 (void)(lib); /* not used */
233}
234
235
236static void *lsys_load (lua_State *L, const char *path, int seeglb) {
237 (void)(path); (void)(seeglb); /* not used */
238 lua_pushliteral(L, DLMSG);
239 return NULL;
240}
241
242
243static lua_CFunction lsys_sym (lua_State *L, void *lib, const char *sym) {
244 (void)(lib); (void)(sym); /* not used */
245 lua_pushliteral(L, DLMSG);
246 return NULL;
247}
248
249/* }====================================================== */
250#endif /* } */
251
252
253/*
254** {==================================================================
255** Set Paths
256** ===================================================================
257*/
258
259/*
260** LUA_PATH_VAR and LUA_CPATH_VAR are the names of the environment
261** variables that Lua check to set its paths.
262*/
263#if !defined(LUA_PATH_VAR)
264#define LUA_PATH_VAR "LUA_PATH"
265#endif
266
267#if !defined(LUA_CPATH_VAR)
268#define LUA_CPATH_VAR "LUA_CPATH"
269#endif
270
271
272#define AUXMARK "\1" /* auxiliary mark */
273
274
275/*
276** return registry.LUA_NOENV as a boolean
277*/
278static int noenv (lua_State *L) {
279 int b;
280 lua_getfield(L, LUA_REGISTRYINDEX, "LUA_NOENV");
281 b = lua_toboolean(L, -1);
282 lua_pop(L, 1); /* remove value */
283 return b;
284}
285
286
287/*
288** Set a path
289*/
290static void setpath (lua_State *L, const char *fieldname,
291 const char *envname,
292 const char *dft) {
293 const char *nver = lua_pushfstring(L, "%s%s", envname, LUA_VERSUFFIX);
294 const char *path = getenv(nver); /* use versioned name */
295 if (path == NULL) /* no environment variable? */
296 path = getenv(envname); /* try unversioned name */
297 if (path == NULL || noenv(L)) /* no environment variable? */
298 lua_pushstring(L, dft); /* use default */
299 else {
300 /* replace ";;" by ";AUXMARK;" and then AUXMARK by default path */
301 path = luaL_gsub(L, path, LUA_PATH_SEP LUA_PATH_SEP,
302 LUA_PATH_SEP AUXMARK LUA_PATH_SEP);
303 luaL_gsub(L, path, AUXMARK, dft);
304 lua_remove(L, -2); /* remove result from 1st 'gsub' */
305 }
306 setprogdir(L);
307 lua_setfield(L, -3, fieldname); /* package[fieldname] = path value */
308 lua_pop(L, 1); /* pop versioned variable name */
309}
310
311/* }================================================================== */
312
313
314/*
315** return registry.CLIBS[path]
316*/
317static void *checkclib (lua_State *L, const char *path) {
318 void *plib;
319 lua_rawgetp(L, LUA_REGISTRYINDEX, &CLIBS);
320 lua_getfield(L, -1, path);
321 plib = lua_touserdata(L, -1); /* plib = CLIBS[path] */
322 lua_pop(L, 2); /* pop CLIBS table and 'plib' */
323 return plib;
324}
325
326
327/*
328** registry.CLIBS[path] = plib -- for queries
329** registry.CLIBS[#CLIBS + 1] = plib -- also keep a list of all libraries
330*/
331static void addtoclib (lua_State *L, const char *path, void *plib) {
332 lua_rawgetp(L, LUA_REGISTRYINDEX, &CLIBS);
333 lua_pushlightuserdata(L, plib);
334 lua_pushvalue(L, -1);
335 lua_setfield(L, -3, path); /* CLIBS[path] = plib */
336 lua_rawseti(L, -2, luaL_len(L, -2) + 1); /* CLIBS[#CLIBS + 1] = plib */
337 lua_pop(L, 1); /* pop CLIBS table */
338}
339
340
341/*
342** __gc tag method for CLIBS table: calls 'lsys_unloadlib' for all lib
343** handles in list CLIBS
344*/
345static int gctm (lua_State *L) {
346 lua_Integer n = luaL_len(L, 1);
347 for (; n >= 1; n--) { /* for each handle, in reverse order */
348 lua_rawgeti(L, 1, n); /* get handle CLIBS[n] */
349 lsys_unloadlib(lua_touserdata(L, -1));
350 lua_pop(L, 1); /* pop handle */
351 }
352 return 0;
353}
354
355
356
357/* error codes for 'lookforfunc' */
358#define ERRLIB 1
359#define ERRFUNC 2
360
361/*
362** Look for a C function named 'sym' in a dynamically loaded library
363** 'path'.
364** First, check whether the library is already loaded; if not, try
365** to load it.
366** Then, if 'sym' is '*', return true (as library has been loaded).
367** Otherwise, look for symbol 'sym' in the library and push a
368** C function with that symbol.
369** Return 0 and 'true' or a function in the stack; in case of
370** errors, return an error code and an error message in the stack.
371*/
372static int lookforfunc (lua_State *L, const char *path, const char *sym) {
373 void *reg = checkclib(L, path); /* check loaded C libraries */
374 if (reg == NULL) { /* must load library? */
375 reg = lsys_load(L, path, *sym == '*'); /* global symbols if 'sym'=='*' */
376 if (reg == NULL) return ERRLIB; /* unable to load library */
377 addtoclib(L, path, reg);
378 }
379 if (*sym == '*') { /* loading only library (no function)? */
380 lua_pushboolean(L, 1); /* return 'true' */
381 return 0; /* no errors */
382 }
383 else {
384 lua_CFunction f = lsys_sym(L, reg, sym);
385 if (f == NULL)
386 return ERRFUNC; /* unable to find function */
387 lua_pushcfunction(L, f); /* else create new function */
388 return 0; /* no errors */
389 }
390}
391
392
393static int ll_loadlib (lua_State *L) {
394 const char *path = luaL_checkstring(L, 1);
395 const char *init = luaL_checkstring(L, 2);
396 int stat = lookforfunc(L, path, init);
397 if (stat == 0) /* no errors? */
398 return 1; /* return the loaded function */
399 else { /* error; error message is on stack top */
400 lua_pushnil(L);
401 lua_insert(L, -2);
402 lua_pushstring(L, (stat == ERRLIB) ? LIB_FAIL : "init");
403 return 3; /* return nil, error message, and where */
404 }
405}
406
407
408
409/*
410** {======================================================
411** 'require' function
412** =======================================================
413*/
414
415
416static int readable (const char *filename) {
417 FILE *f = fopen(filename, "r"); /* try to open file */
418 if (f == NULL) return 0; /* open failed */
419 fclose(f);
420 return 1;
421}
422
423
424static const char *pushnexttemplate (lua_State *L, const char *path) {
425 const char *l;
426 while (*path == *LUA_PATH_SEP) path++; /* skip separators */
427 if (*path == '\0') return NULL; /* no more templates */
428 l = strchr(path, *LUA_PATH_SEP); /* find next separator */
429 if (l == NULL) l = path + strlen(path);
430 lua_pushlstring(L, path, l - path); /* template */
431 return l;
432}
433
434
435static const char *searchpath (lua_State *L, const char *name,
436 const char *path,
437 const char *sep,
438 const char *dirsep) {
439 luaL_Buffer msg; /* to build error message */
440 luaL_buffinit(L, &msg);
441 if (*sep != '\0') /* non-empty separator? */
442 name = luaL_gsub(L, name, sep, dirsep); /* replace it by 'dirsep' */
443 while ((path = pushnexttemplate(L, path)) != NULL) {
444 const char *filename = luaL_gsub(L, lua_tostring(L, -1),
445 LUA_PATH_MARK, name);
446 lua_remove(L, -2); /* remove path template */
447 if (readable(filename)) /* does file exist and is readable? */
448 return filename; /* return that file name */
449 lua_pushfstring(L, "\n\tno file '%s'", filename);
450 lua_remove(L, -2); /* remove file name */
451 luaL_addvalue(&msg); /* concatenate error msg. entry */
452 }
453 luaL_pushresult(&msg); /* create error message */
454 return NULL; /* not found */
455}
456
457
458static int ll_searchpath (lua_State *L) {
459 const char *f = searchpath(L, luaL_checkstring(L, 1),
460 luaL_checkstring(L, 2),
461 luaL_optstring(L, 3, "."),
462 luaL_optstring(L, 4, LUA_DIRSEP));
463 if (f != NULL) return 1;
464 else { /* error message is on top of the stack */
465 lua_pushnil(L);
466 lua_insert(L, -2);
467 return 2; /* return nil + error message */
468 }
469}
470
471
472static const char *findfile (lua_State *L, const char *name,
473 const char *pname,
474 const char *dirsep) {
475 const char *path;
476 lua_getfield(L, lua_upvalueindex(1), pname);
477 path = lua_tostring(L, -1);
478 if (path == NULL)
479 luaL_error(L, "'package.%s' must be a string", pname);
480 return searchpath(L, name, path, ".", dirsep);
481}
482
483
484static int checkload (lua_State *L, int stat, const char *filename) {
485 if (stat) { /* module loaded successfully? */
486 lua_pushstring(L, filename); /* will be 2nd argument to module */
487 return 2; /* return open function and file name */
488 }
489 else
490 return luaL_error(L, "error loading module '%s' from file '%s':\n\t%s",
491 lua_tostring(L, 1), filename, lua_tostring(L, -1));
492}
493
494
495static int searcher_Lua (lua_State *L) {
496 const char *filename;
497 const char *name = luaL_checkstring(L, 1);
498 filename = findfile(L, name, "path", LUA_LSUBSEP);
499 if (filename == NULL) return 1; /* module not found in this path */
500 return checkload(L, (luaL_loadfile(L, filename) == LUA_OK), filename);
501}
502
503
504/*
505** Try to find a load function for module 'modname' at file 'filename'.
506** First, change '.' to '_' in 'modname'; then, if 'modname' has
507** the form X-Y (that is, it has an "ignore mark"), build a function
508** name "luaopen_X" and look for it. (For compatibility, if that
509** fails, it also tries "luaopen_Y".) If there is no ignore mark,
510** look for a function named "luaopen_modname".
511*/
512static int loadfunc (lua_State *L, const char *filename, const char *modname) {
513 const char *openfunc;
514 const char *mark;
515 modname = luaL_gsub(L, modname, ".", LUA_OFSEP);
516 mark = strchr(modname, *LUA_IGMARK);
517 if (mark) {
518 int stat;
519 openfunc = lua_pushlstring(L, modname, mark - modname);
520 openfunc = lua_pushfstring(L, LUA_POF"%s", openfunc);
521 stat = lookforfunc(L, filename, openfunc);
522 if (stat != ERRFUNC) return stat;
523 modname = mark + 1; /* else go ahead and try old-style name */
524 }
525 openfunc = lua_pushfstring(L, LUA_POF"%s", modname);
526 return lookforfunc(L, filename, openfunc);
527}
528
529
530static int searcher_C (lua_State *L) {
531 const char *name = luaL_checkstring(L, 1);
532 const char *filename = findfile(L, name, "cpath", LUA_CSUBSEP);
533 if (filename == NULL) return 1; /* module not found in this path */
534 return checkload(L, (loadfunc(L, filename, name) == 0), filename);
535}
536
537
538static int searcher_Croot (lua_State *L) {
539 const char *filename;
540 const char *name = luaL_checkstring(L, 1);
541 const char *p = strchr(name, '.');
542 int stat;
543 if (p == NULL) return 0; /* is root */
544 lua_pushlstring(L, name, p - name);
545 filename = findfile(L, lua_tostring(L, -1), "cpath", LUA_CSUBSEP);
546 if (filename == NULL) return 1; /* root not found */
547 if ((stat = loadfunc(L, filename, name)) != 0) {
548 if (stat != ERRFUNC)
549 return checkload(L, 0, filename); /* real error */
550 else { /* open function not found */
551 lua_pushfstring(L, "\n\tno module '%s' in file '%s'", name, filename);
552 return 1;
553 }
554 }
555 lua_pushstring(L, filename); /* will be 2nd argument to module */
556 return 2;
557}
558
559
560static int searcher_preload (lua_State *L) {
561 const char *name = luaL_checkstring(L, 1);
562 lua_getfield(L, LUA_REGISTRYINDEX, LUA_PRELOAD_TABLE);
563 if (lua_getfield(L, -1, name) == LUA_TNIL) /* not found? */
564 lua_pushfstring(L, "\n\tno field package.preload['%s']", name);
565 return 1;
566}
567
568
569static void findloader (lua_State *L, const char *name) {
570 int i;
571 luaL_Buffer msg; /* to build error message */
572 luaL_buffinit(L, &msg);
573 /* push 'package.searchers' to index 3 in the stack */
574 if (lua_getfield(L, lua_upvalueindex(1), "searchers") != LUA_TTABLE)
575 luaL_error(L, "'package.searchers' must be a table");
576 /* iterate over available searchers to find a loader */
577 for (i = 1; ; i++) {
578 if (lua_rawgeti(L, 3, i) == LUA_TNIL) { /* no more searchers? */
579 lua_pop(L, 1); /* remove nil */
580 luaL_pushresult(&msg); /* create error message */
581 luaL_error(L, "module '%s' not found:%s", name, lua_tostring(L, -1));
582 }
583 lua_pushstring(L, name);
584 lua_call(L, 1, 2); /* call it */
585 if (lua_isfunction(L, -2)) /* did it find a loader? */
586 return; /* module loader found */
587 else if (lua_isstring(L, -2)) { /* searcher returned error message? */
588 lua_pop(L, 1); /* remove extra return */
589 luaL_addvalue(&msg); /* concatenate error message */
590 }
591 else
592 lua_pop(L, 2); /* remove both returns */
593 }
594}
595
596
597static int ll_require (lua_State *L) {
598 const char *name = luaL_checkstring(L, 1);
599 lua_settop(L, 1); /* LOADED table will be at index 2 */
600 lua_getfield(L, LUA_REGISTRYINDEX, LUA_LOADED_TABLE);
601 lua_getfield(L, 2, name); /* LOADED[name] */
602 if (lua_toboolean(L, -1)) /* is it there? */
603 return 1; /* package is already loaded */
604 /* else must load package */
605 lua_pop(L, 1); /* remove 'getfield' result */
606 findloader(L, name);
607 lua_pushstring(L, name); /* pass name as argument to module loader */
608 lua_insert(L, -2); /* name is 1st argument (before search data) */
609 lua_call(L, 2, 1); /* run loader to load module */
610 if (!lua_isnil(L, -1)) /* non-nil return? */
611 lua_setfield(L, 2, name); /* LOADED[name] = returned value */
612 if (lua_getfield(L, 2, name) == LUA_TNIL) { /* module set no value? */
613 lua_pushboolean(L, 1); /* use true as result */
614 lua_pushvalue(L, -1); /* extra copy to be returned */
615 lua_setfield(L, 2, name); /* LOADED[name] = true */
616 }
617 return 1;
618}
619
620/* }====================================================== */
621
622
623
624/*
625** {======================================================
626** 'module' function
627** =======================================================
628*/
629#if defined(LUA_COMPAT_MODULE)
630
631/*
632** changes the environment variable of calling function
633*/
634static void set_env (lua_State *L) {
635 lua_Debug ar;
636 if (lua_getstack(L, 1, &ar) == 0 ||
637 lua_getinfo(L, "f", &ar) == 0 || /* get calling function */
638 lua_iscfunction(L, -1))
639 luaL_error(L, "'module' not called from a Lua function");
640 lua_pushvalue(L, -2); /* copy new environment table to top */
641 lua_setupvalue(L, -2, 1);
642 lua_pop(L, 1); /* remove function */
643}
644
645
646static void dooptions (lua_State *L, int n) {
647 int i;
648 for (i = 2; i <= n; i++) {
649 if (lua_isfunction(L, i)) { /* avoid 'calling' extra info. */
650 lua_pushvalue(L, i); /* get option (a function) */
651 lua_pushvalue(L, -2); /* module */
652 lua_call(L, 1, 0);
653 }
654 }
655}
656
657
658static void modinit (lua_State *L, const char *modname) {
659 const char *dot;
660 lua_pushvalue(L, -1);
661 lua_setfield(L, -2, "_M"); /* module._M = module */
662 lua_pushstring(L, modname);
663 lua_setfield(L, -2, "_NAME");
664 dot = strrchr(modname, '.'); /* look for last dot in module name */
665 if (dot == NULL) dot = modname;
666 else dot++;
667 /* set _PACKAGE as package name (full module name minus last part) */
668 lua_pushlstring(L, modname, dot - modname);
669 lua_setfield(L, -2, "_PACKAGE");
670}
671
672
673static int ll_module (lua_State *L) {
674 const char *modname = luaL_checkstring(L, 1);
675 int lastarg = lua_gettop(L); /* last parameter */
676 luaL_pushmodule(L, modname, 1); /* get/create module table */
677 /* check whether table already has a _NAME field */
678 if (lua_getfield(L, -1, "_NAME") != LUA_TNIL)
679 lua_pop(L, 1); /* table is an initialized module */
680 else { /* no; initialize it */
681 lua_pop(L, 1);
682 modinit(L, modname);
683 }
684 lua_pushvalue(L, -1);
685 set_env(L);
686 dooptions(L, lastarg);
687 return 1;
688}
689
690
691static int ll_seeall (lua_State *L) {
692 luaL_checktype(L, 1, LUA_TTABLE);
693 if (!lua_getmetatable(L, 1)) {
694 lua_createtable(L, 0, 1); /* create new metatable */
695 lua_pushvalue(L, -1);
696 lua_setmetatable(L, 1);
697 }
698 lua_pushglobaltable(L);
699 lua_setfield(L, -2, "__index"); /* mt.__index = _G */
700 return 0;
701}
702
703#endif
704/* }====================================================== */
705
706
707
708static const luaL_Reg pk_funcs[] = {
709 {"loadlib", ll_loadlib},
710 {"searchpath", ll_searchpath},
711#if defined(LUA_COMPAT_MODULE)
712 {"seeall", ll_seeall},
713#endif
714 /* placeholders */
715 {"preload", NULL},
716 {"cpath", NULL},
717 {"path", NULL},
718 {"searchers", NULL},
719 {"loaded", NULL},
720 {NULL, NULL}
721};
722
723
724static const luaL_Reg ll_funcs[] = {
725#if defined(LUA_COMPAT_MODULE)
726 {"module", ll_module},
727#endif
728 {"require", ll_require},
729 {NULL, NULL}
730};
731
732
733static void createsearcherstable (lua_State *L) {
734 static const lua_CFunction searchers[] =
735 {searcher_preload, searcher_Lua, searcher_C, searcher_Croot, NULL};
736 int i;
737 /* create 'searchers' table */
738 lua_createtable(L, sizeof(searchers)/sizeof(searchers[0]) - 1, 0);
739 /* fill it with predefined searchers */
740 for (i=0; searchers[i] != NULL; i++) {
741 lua_pushvalue(L, -2); /* set 'package' as upvalue for all searchers */
742 lua_pushcclosure(L, searchers[i], 1);
743 lua_rawseti(L, -2, i+1);
744 }
745#if defined(LUA_COMPAT_LOADERS)
746 lua_pushvalue(L, -1); /* make a copy of 'searchers' table */
747 lua_setfield(L, -3, "loaders"); /* put it in field 'loaders' */
748#endif
749 lua_setfield(L, -2, "searchers"); /* put it in field 'searchers' */
750}
751
752
753/*
754** create table CLIBS to keep track of loaded C libraries,
755** setting a finalizer to close all libraries when closing state.
756*/
757static void createclibstable (lua_State *L) {
758 lua_newtable(L); /* create CLIBS table */
759 lua_createtable(L, 0, 1); /* create metatable for CLIBS */
760 lua_pushcfunction(L, gctm);
761 lua_setfield(L, -2, "__gc"); /* set finalizer for CLIBS table */
762 lua_setmetatable(L, -2);
763 lua_rawsetp(L, LUA_REGISTRYINDEX, &CLIBS); /* set CLIBS table in registry */
764}
765
766
767LUAMOD_API int luaopen_package (lua_State *L) {
768 createclibstable(L);
769 luaL_newlib(L, pk_funcs); /* create 'package' table */
770 createsearcherstable(L);
771 /* set paths */
772 setpath(L, "path", LUA_PATH_VAR, LUA_PATH_DEFAULT);
773 setpath(L, "cpath", LUA_CPATH_VAR, LUA_CPATH_DEFAULT);
774 /* store config information */
775 lua_pushliteral(L, LUA_DIRSEP "\n" LUA_PATH_SEP "\n" LUA_PATH_MARK "\n"
776 LUA_EXEC_DIR "\n" LUA_IGMARK "\n");
777 lua_setfield(L, -2, "config");
778 /* set field 'loaded' */
779 luaL_getsubtable(L, LUA_REGISTRYINDEX, LUA_LOADED_TABLE);
780 lua_setfield(L, -2, "loaded");
781 /* set field 'preload' */
782 luaL_getsubtable(L, LUA_REGISTRYINDEX, LUA_PRELOAD_TABLE);
783 lua_setfield(L, -2, "preload");
784 lua_pushglobaltable(L);
785 lua_pushvalue(L, -2); /* set 'package' as upvalue for next lib */
786 luaL_setfuncs(L, ll_funcs, 1); /* open lib into global table */
787 lua_pop(L, 1); /* pop global table */
788 return 1; /* return 'package' table */
789}
790
791