1/*
2** $Id: loadlib.c $
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_CSUBSEP is the character that replaces dots in submodule names
29** when searching for a C loader.
30** LUA_LSUBSEP is the character that replaces dots in submodule names
31** when searching for a Lua loader.
32*/
33#if !defined(LUA_CSUBSEP)
34#define LUA_CSUBSEP LUA_DIRSEP
35#endif
36
37#if !defined(LUA_LSUBSEP)
38#define LUA_LSUBSEP LUA_DIRSEP
39#endif
40
41
42/* prefix for open functions in C libraries */
43#define LUA_POF "luaopen_"
44
45/* separator for open functions in C libraries */
46#define LUA_OFSEP "_"
47
48
49/*
50** key for table in the registry that keeps handles
51** for all loaded C libraries
52*/
53static const char *const CLIBS = "_CLIBS";
54
55#define LIB_FAIL "open"
56
57
58#define setprogdir(L) ((void)0)
59
60
61/*
62** Special type equivalent to '(void*)' for functions in gcc
63** (to suppress warnings when converting function pointers)
64*/
65typedef void (*voidf)(void);
66
67
68/*
69** system-dependent functions
70*/
71
72/*
73** unload library 'lib'
74*/
75static void lsys_unloadlib (void *lib);
76
77/*
78** load C library in file 'path'. If 'seeglb', load with all names in
79** the library global.
80** Returns the library; in case of error, returns NULL plus an
81** error string in the stack.
82*/
83static void *lsys_load (lua_State *L, const char *path, int seeglb);
84
85/*
86** Try to find a function named 'sym' in library 'lib'.
87** Returns the function; in case of error, returns NULL plus an
88** error string in the stack.
89*/
90static lua_CFunction lsys_sym (lua_State *L, void *lib, const char *sym);
91
92
93
94
95#if defined(LUA_USE_DLOPEN) /* { */
96/*
97** {========================================================================
98** This is an implementation of loadlib based on the dlfcn interface.
99** The dlfcn interface is available in Linux, SunOS, Solaris, IRIX, FreeBSD,
100** NetBSD, AIX 4.2, HPUX 11, and probably most other Unix flavors, at least
101** as an emulation layer on top of native functions.
102** =========================================================================
103*/
104
105#include <dlfcn.h>
106
107/*
108** Macro to convert pointer-to-void* to pointer-to-function. This cast
109** is undefined according to ISO C, but POSIX assumes that it works.
110** (The '__extension__' in gnu compilers is only to avoid warnings.)
111*/
112#if defined(__GNUC__)
113#define cast_func(p) (__extension__ (lua_CFunction)(p))
114#else
115#define cast_func(p) ((lua_CFunction)(p))
116#endif
117
118
119static void lsys_unloadlib (void *lib) {
120 dlclose(lib);
121}
122
123
124static void *lsys_load (lua_State *L, const char *path, int seeglb) {
125 void *lib = dlopen(path, RTLD_NOW | (seeglb ? RTLD_GLOBAL : RTLD_LOCAL));
126 if (l_unlikely(lib == NULL))
127 lua_pushstring(L, dlerror());
128 return lib;
129}
130
131
132static lua_CFunction lsys_sym (lua_State *L, void *lib, const char *sym) {
133 lua_CFunction f = cast_func(dlsym(lib, sym));
134 if (l_unlikely(f == NULL))
135 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)(voidf)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
273/*
274** return registry.LUA_NOENV as a boolean
275*/
276static int noenv (lua_State *L) {
277 int b;
278 lua_getfield(L, LUA_REGISTRYINDEX, "LUA_NOENV");
279 b = lua_toboolean(L, -1);
280 lua_pop(L, 1); /* remove value */
281 return b;
282}
283
284
285/*
286** Set a path
287*/
288static void setpath (lua_State *L, const char *fieldname,
289 const char *envname,
290 const char *dft) {
291 const char *dftmark;
292 const char *nver = lua_pushfstring(L, "%s%s", envname, LUA_VERSUFFIX);
293 const char *path = getenv(nver); /* try versioned name */
294 if (path == NULL) /* no versioned environment variable? */
295 path = getenv(envname); /* try unversioned name */
296 if (path == NULL || noenv(L)) /* no environment variable? */
297 lua_pushstring(L, dft); /* use default */
298 else if ((dftmark = strstr(path, LUA_PATH_SEP LUA_PATH_SEP)) == NULL)
299 lua_pushstring(L, path); /* nothing to change */
300 else { /* path contains a ";;": insert default path in its place */
301 size_t len = strlen(path);
302 luaL_Buffer b;
303 luaL_buffinit(L, &b);
304 if (path < dftmark) { /* is there a prefix before ';;'? */
305 luaL_addlstring(&b, path, dftmark - path); /* add it */
306 luaL_addchar(&b, *LUA_PATH_SEP);
307 }
308 luaL_addstring(&b, dft); /* add default */
309 if (dftmark < path + len - 2) { /* is there a suffix after ';;'? */
310 luaL_addchar(&b, *LUA_PATH_SEP);
311 luaL_addlstring(&b, dftmark + 2, (path + len - 2) - dftmark);
312 }
313 luaL_pushresult(&b);
314 }
315 setprogdir(L);
316 lua_setfield(L, -3, fieldname); /* package[fieldname] = path value */
317 lua_pop(L, 1); /* pop versioned variable name ('nver') */
318}
319
320/* }================================================================== */
321
322
323/*
324** return registry.CLIBS[path]
325*/
326static void *checkclib (lua_State *L, const char *path) {
327 void *plib;
328 lua_getfield(L, LUA_REGISTRYINDEX, CLIBS);
329 lua_getfield(L, -1, path);
330 plib = lua_touserdata(L, -1); /* plib = CLIBS[path] */
331 lua_pop(L, 2); /* pop CLIBS table and 'plib' */
332 return plib;
333}
334
335
336/*
337** registry.CLIBS[path] = plib -- for queries
338** registry.CLIBS[#CLIBS + 1] = plib -- also keep a list of all libraries
339*/
340static void addtoclib (lua_State *L, const char *path, void *plib) {
341 lua_getfield(L, LUA_REGISTRYINDEX, CLIBS);
342 lua_pushlightuserdata(L, plib);
343 lua_pushvalue(L, -1);
344 lua_setfield(L, -3, path); /* CLIBS[path] = plib */
345 lua_rawseti(L, -2, luaL_len(L, -2) + 1); /* CLIBS[#CLIBS + 1] = plib */
346 lua_pop(L, 1); /* pop CLIBS table */
347}
348
349
350/*
351** __gc tag method for CLIBS table: calls 'lsys_unloadlib' for all lib
352** handles in list CLIBS
353*/
354static int gctm (lua_State *L) {
355 lua_Integer n = luaL_len(L, 1);
356 for (; n >= 1; n--) { /* for each handle, in reverse order */
357 lua_rawgeti(L, 1, n); /* get handle CLIBS[n] */
358 lsys_unloadlib(lua_touserdata(L, -1));
359 lua_pop(L, 1); /* pop handle */
360 }
361 return 0;
362}
363
364
365
366/* error codes for 'lookforfunc' */
367#define ERRLIB 1
368#define ERRFUNC 2
369
370/*
371** Look for a C function named 'sym' in a dynamically loaded library
372** 'path'.
373** First, check whether the library is already loaded; if not, try
374** to load it.
375** Then, if 'sym' is '*', return true (as library has been loaded).
376** Otherwise, look for symbol 'sym' in the library and push a
377** C function with that symbol.
378** Return 0 and 'true' or a function in the stack; in case of
379** errors, return an error code and an error message in the stack.
380*/
381static int lookforfunc (lua_State *L, const char *path, const char *sym) {
382 void *reg = checkclib(L, path); /* check loaded C libraries */
383 if (reg == NULL) { /* must load library? */
384 reg = lsys_load(L, path, *sym == '*'); /* global symbols if 'sym'=='*' */
385 if (reg == NULL) return ERRLIB; /* unable to load library */
386 addtoclib(L, path, reg);
387 }
388 if (*sym == '*') { /* loading only library (no function)? */
389 lua_pushboolean(L, 1); /* return 'true' */
390 return 0; /* no errors */
391 }
392 else {
393 lua_CFunction f = lsys_sym(L, reg, sym);
394 if (f == NULL)
395 return ERRFUNC; /* unable to find function */
396 lua_pushcfunction(L, f); /* else create new function */
397 return 0; /* no errors */
398 }
399}
400
401
402static int ll_loadlib (lua_State *L) {
403 const char *path = luaL_checkstring(L, 1);
404 const char *init = luaL_checkstring(L, 2);
405 int stat = lookforfunc(L, path, init);
406 if (l_likely(stat == 0)) /* no errors? */
407 return 1; /* return the loaded function */
408 else { /* error; error message is on stack top */
409 luaL_pushfail(L);
410 lua_insert(L, -2);
411 lua_pushstring(L, (stat == ERRLIB) ? LIB_FAIL : "init");
412 return 3; /* return fail, error message, and where */
413 }
414}
415
416
417
418/*
419** {======================================================
420** 'require' function
421** =======================================================
422*/
423
424
425static int readable (const char *filename) {
426 FILE *f = fopen(filename, "r"); /* try to open file */
427 if (f == NULL) return 0; /* open failed */
428 fclose(f);
429 return 1;
430}
431
432
433/*
434** Get the next name in '*path' = 'name1;name2;name3;...', changing
435** the ending ';' to '\0' to create a zero-terminated string. Return
436** NULL when list ends.
437*/
438static const char *getnextfilename (char **path, char *end) {
439 char *sep;
440 char *name = *path;
441 if (name == end)
442 return NULL; /* no more names */
443 else if (*name == '\0') { /* from previous iteration? */
444 *name = *LUA_PATH_SEP; /* restore separator */
445 name++; /* skip it */
446 }
447 sep = strchr(name, *LUA_PATH_SEP); /* find next separator */
448 if (sep == NULL) /* separator not found? */
449 sep = end; /* name goes until the end */
450 *sep = '\0'; /* finish file name */
451 *path = sep; /* will start next search from here */
452 return name;
453}
454
455
456/*
457** Given a path such as ";blabla.so;blublu.so", pushes the string
458**
459** no file 'blabla.so'
460** no file 'blublu.so'
461*/
462static void pusherrornotfound (lua_State *L, const char *path) {
463 luaL_Buffer b;
464 luaL_buffinit(L, &b);
465 luaL_addstring(&b, "no file '");
466 luaL_addgsub(&b, path, LUA_PATH_SEP, "'\n\tno file '");
467 luaL_addstring(&b, "'");
468 luaL_pushresult(&b);
469}
470
471
472static const char *searchpath (lua_State *L, const char *name,
473 const char *path,
474 const char *sep,
475 const char *dirsep) {
476 luaL_Buffer buff;
477 char *pathname; /* path with name inserted */
478 char *endpathname; /* its end */
479 const char *filename;
480 /* separator is non-empty and appears in 'name'? */
481 if (*sep != '\0' && strchr(name, *sep) != NULL)
482 name = luaL_gsub(L, name, sep, dirsep); /* replace it by 'dirsep' */
483 luaL_buffinit(L, &buff);
484 /* add path to the buffer, replacing marks ('?') with the file name */
485 luaL_addgsub(&buff, path, LUA_PATH_MARK, name);
486 luaL_addchar(&buff, '\0');
487 pathname = luaL_buffaddr(&buff); /* writable list of file names */
488 endpathname = pathname + luaL_bufflen(&buff) - 1;
489 while ((filename = getnextfilename(&pathname, endpathname)) != NULL) {
490 if (readable(filename)) /* does file exist and is readable? */
491 return lua_pushstring(L, filename); /* save and return name */
492 }
493 luaL_pushresult(&buff); /* push path to create error message */
494 pusherrornotfound(L, lua_tostring(L, -1)); /* create error message */
495 return NULL; /* not found */
496}
497
498
499static int ll_searchpath (lua_State *L) {
500 const char *f = searchpath(L, luaL_checkstring(L, 1),
501 luaL_checkstring(L, 2),
502 luaL_optstring(L, 3, "."),
503 luaL_optstring(L, 4, LUA_DIRSEP));
504 if (f != NULL) return 1;
505 else { /* error message is on top of the stack */
506 luaL_pushfail(L);
507 lua_insert(L, -2);
508 return 2; /* return fail + error message */
509 }
510}
511
512
513static const char *findfile (lua_State *L, const char *name,
514 const char *pname,
515 const char *dirsep) {
516 const char *path;
517 lua_getfield(L, lua_upvalueindex(1), pname);
518 path = lua_tostring(L, -1);
519 if (l_unlikely(path == NULL))
520 luaL_error(L, "'package.%s' must be a string", pname);
521 return searchpath(L, name, path, ".", dirsep);
522}
523
524
525static int checkload (lua_State *L, int stat, const char *filename) {
526 if (l_likely(stat)) { /* module loaded successfully? */
527 lua_pushstring(L, filename); /* will be 2nd argument to module */
528 return 2; /* return open function and file name */
529 }
530 else
531 return luaL_error(L, "error loading module '%s' from file '%s':\n\t%s",
532 lua_tostring(L, 1), filename, lua_tostring(L, -1));
533}
534
535
536static int searcher_Lua (lua_State *L) {
537 const char *filename;
538 const char *name = luaL_checkstring(L, 1);
539 filename = findfile(L, name, "path", LUA_LSUBSEP);
540 if (filename == NULL) return 1; /* module not found in this path */
541 return checkload(L, (luaL_loadfile(L, filename) == LUA_OK), filename);
542}
543
544
545/*
546** Try to find a load function for module 'modname' at file 'filename'.
547** First, change '.' to '_' in 'modname'; then, if 'modname' has
548** the form X-Y (that is, it has an "ignore mark"), build a function
549** name "luaopen_X" and look for it. (For compatibility, if that
550** fails, it also tries "luaopen_Y".) If there is no ignore mark,
551** look for a function named "luaopen_modname".
552*/
553static int loadfunc (lua_State *L, const char *filename, const char *modname) {
554 const char *openfunc;
555 const char *mark;
556 modname = luaL_gsub(L, modname, ".", LUA_OFSEP);
557 mark = strchr(modname, *LUA_IGMARK);
558 if (mark) {
559 int stat;
560 openfunc = lua_pushlstring(L, modname, mark - modname);
561 openfunc = lua_pushfstring(L, LUA_POF"%s", openfunc);
562 stat = lookforfunc(L, filename, openfunc);
563 if (stat != ERRFUNC) return stat;
564 modname = mark + 1; /* else go ahead and try old-style name */
565 }
566 openfunc = lua_pushfstring(L, LUA_POF"%s", modname);
567 return lookforfunc(L, filename, openfunc);
568}
569
570
571static int searcher_C (lua_State *L) {
572 const char *name = luaL_checkstring(L, 1);
573 const char *filename = findfile(L, name, "cpath", LUA_CSUBSEP);
574 if (filename == NULL) return 1; /* module not found in this path */
575 return checkload(L, (loadfunc(L, filename, name) == 0), filename);
576}
577
578
579static int searcher_Croot (lua_State *L) {
580 const char *filename;
581 const char *name = luaL_checkstring(L, 1);
582 const char *p = strchr(name, '.');
583 int stat;
584 if (p == NULL) return 0; /* is root */
585 lua_pushlstring(L, name, p - name);
586 filename = findfile(L, lua_tostring(L, -1), "cpath", LUA_CSUBSEP);
587 if (filename == NULL) return 1; /* root not found */
588 if ((stat = loadfunc(L, filename, name)) != 0) {
589 if (stat != ERRFUNC)
590 return checkload(L, 0, filename); /* real error */
591 else { /* open function not found */
592 lua_pushfstring(L, "no module '%s' in file '%s'", name, filename);
593 return 1;
594 }
595 }
596 lua_pushstring(L, filename); /* will be 2nd argument to module */
597 return 2;
598}
599
600
601static int searcher_preload (lua_State *L) {
602 const char *name = luaL_checkstring(L, 1);
603 lua_getfield(L, LUA_REGISTRYINDEX, LUA_PRELOAD_TABLE);
604 if (lua_getfield(L, -1, name) == LUA_TNIL) { /* not found? */
605 lua_pushfstring(L, "no field package.preload['%s']", name);
606 return 1;
607 }
608 else {
609 lua_pushliteral(L, ":preload:");
610 return 2;
611 }
612}
613
614
615static void findloader (lua_State *L, const char *name) {
616 int i;
617 luaL_Buffer msg; /* to build error message */
618 /* push 'package.searchers' to index 3 in the stack */
619 if (l_unlikely(lua_getfield(L, lua_upvalueindex(1), "searchers")
620 != LUA_TTABLE))
621 luaL_error(L, "'package.searchers' must be a table");
622 luaL_buffinit(L, &msg);
623 /* iterate over available searchers to find a loader */
624 for (i = 1; ; i++) {
625 luaL_addstring(&msg, "\n\t"); /* error-message prefix */
626 if (l_unlikely(lua_rawgeti(L, 3, i) == LUA_TNIL)) { /* no more searchers? */
627 lua_pop(L, 1); /* remove nil */
628 luaL_buffsub(&msg, 2); /* remove prefix */
629 luaL_pushresult(&msg); /* create error message */
630 luaL_error(L, "module '%s' not found:%s", name, lua_tostring(L, -1));
631 }
632 lua_pushstring(L, name);
633 lua_call(L, 1, 2); /* call it */
634 if (lua_isfunction(L, -2)) /* did it find a loader? */
635 return; /* module loader found */
636 else if (lua_isstring(L, -2)) { /* searcher returned error message? */
637 lua_pop(L, 1); /* remove extra return */
638 luaL_addvalue(&msg); /* concatenate error message */
639 }
640 else { /* no error message */
641 lua_pop(L, 2); /* remove both returns */
642 luaL_buffsub(&msg, 2); /* remove prefix */
643 }
644 }
645}
646
647
648static int ll_require (lua_State *L) {
649 const char *name = luaL_checkstring(L, 1);
650 lua_settop(L, 1); /* LOADED table will be at index 2 */
651 lua_getfield(L, LUA_REGISTRYINDEX, LUA_LOADED_TABLE);
652 lua_getfield(L, 2, name); /* LOADED[name] */
653 if (lua_toboolean(L, -1)) /* is it there? */
654 return 1; /* package is already loaded */
655 /* else must load package */
656 lua_pop(L, 1); /* remove 'getfield' result */
657 findloader(L, name);
658 lua_rotate(L, -2, 1); /* function <-> loader data */
659 lua_pushvalue(L, 1); /* name is 1st argument to module loader */
660 lua_pushvalue(L, -3); /* loader data is 2nd argument */
661 /* stack: ...; loader data; loader function; mod. name; loader data */
662 lua_call(L, 2, 1); /* run loader to load module */
663 /* stack: ...; loader data; result from loader */
664 if (!lua_isnil(L, -1)) /* non-nil return? */
665 lua_setfield(L, 2, name); /* LOADED[name] = returned value */
666 else
667 lua_pop(L, 1); /* pop nil */
668 if (lua_getfield(L, 2, name) == LUA_TNIL) { /* module set no value? */
669 lua_pushboolean(L, 1); /* use true as result */
670 lua_copy(L, -1, -2); /* replace loader result */
671 lua_setfield(L, 2, name); /* LOADED[name] = true */
672 }
673 lua_rotate(L, -2, 1); /* loader data <-> module result */
674 return 2; /* return module result and loader data */
675}
676
677/* }====================================================== */
678
679
680
681
682static const luaL_Reg pk_funcs[] = {
683 {"loadlib", ll_loadlib},
684 {"searchpath", ll_searchpath},
685 /* placeholders */
686 {"preload", NULL},
687 {"cpath", NULL},
688 {"path", NULL},
689 {"searchers", NULL},
690 {"loaded", NULL},
691 {NULL, NULL}
692};
693
694
695static const luaL_Reg ll_funcs[] = {
696 {"require", ll_require},
697 {NULL, NULL}
698};
699
700
701static void createsearcherstable (lua_State *L) {
702 static const lua_CFunction searchers[] = {
703 searcher_preload,
704 searcher_Lua,
705 searcher_C,
706 searcher_Croot,
707 NULL
708 };
709 int i;
710 /* create 'searchers' table */
711 lua_createtable(L, sizeof(searchers)/sizeof(searchers[0]) - 1, 0);
712 /* fill it with predefined searchers */
713 for (i=0; searchers[i] != NULL; i++) {
714 lua_pushvalue(L, -2); /* set 'package' as upvalue for all searchers */
715 lua_pushcclosure(L, searchers[i], 1);
716 lua_rawseti(L, -2, i+1);
717 }
718 lua_setfield(L, -2, "searchers"); /* put it in field 'searchers' */
719}
720
721
722/*
723** create table CLIBS to keep track of loaded C libraries,
724** setting a finalizer to close all libraries when closing state.
725*/
726static void createclibstable (lua_State *L) {
727 luaL_getsubtable(L, LUA_REGISTRYINDEX, CLIBS); /* create CLIBS table */
728 lua_createtable(L, 0, 1); /* create metatable for CLIBS */
729 lua_pushcfunction(L, gctm);
730 lua_setfield(L, -2, "__gc"); /* set finalizer for CLIBS table */
731 lua_setmetatable(L, -2);
732}
733
734
735LUAMOD_API int luaopen_package (lua_State *L) {
736 createclibstable(L);
737 luaL_newlib(L, pk_funcs); /* create 'package' table */
738 createsearcherstable(L);
739 /* set paths */
740 setpath(L, "path", LUA_PATH_VAR, LUA_PATH_DEFAULT);
741 setpath(L, "cpath", LUA_CPATH_VAR, LUA_CPATH_DEFAULT);
742 /* store config information */
743 lua_pushliteral(L, LUA_DIRSEP "\n" LUA_PATH_SEP "\n" LUA_PATH_MARK "\n"
744 LUA_EXEC_DIR "\n" LUA_IGMARK "\n");
745 lua_setfield(L, -2, "config");
746 /* set field 'loaded' */
747 luaL_getsubtable(L, LUA_REGISTRYINDEX, LUA_LOADED_TABLE);
748 lua_setfield(L, -2, "loaded");
749 /* set field 'preload' */
750 luaL_getsubtable(L, LUA_REGISTRYINDEX, LUA_PRELOAD_TABLE);
751 lua_setfield(L, -2, "preload");
752 lua_pushglobaltable(L);
753 lua_pushvalue(L, -2); /* set 'package' as upvalue for next lib */
754 luaL_setfuncs(L, ll_funcs, 1); /* open lib into global table */
755 lua_pop(L, 1); /* pop global table */
756 return 1; /* return 'package' table */
757}
758