GCC Code Coverage Report

Line	Branch	Decision	Exec	Source
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				*/
53				static 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				*/
65				typedef void (*voidf)(void);
66
67
68				/*
69				** system-dependent functions
70				*/
71
72				/*
73				** unload library 'lib'
74				*/
75				static 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				*/
83				static 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				*/
90				static 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
119				static void lsys_unloadlib (void *lib) {
120				dlclose(lib);
121				}
122
123
124				static 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
132				static 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				*/
168				static 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
185				static 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
195				static void lsys_unloadlib (void *lib) {
196				FreeLibrary((HMODULE)lib);
197				}
198
199
200				static 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
208				static 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
231			✗	static void lsys_unloadlib (void *lib) {
232				(void)(lib); /* not used */
233			✗	}
234
235
236			✗	static 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
243			✗	static 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				*/
276			✗	static 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				*/
288			✗	static 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				*/
326			✗	static 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				*/
340			✗	static 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				*/
354			✗	static 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				*/
381			✗	static 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
402			✗	static 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
425			✗	static 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				*/
438			✗	static 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				*/
462			✗	static 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
472			✗	static 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
499			✗	static 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
513			✗	static 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
525			✗	static 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
536			✗	static 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				*/
553			✗	static 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
571			✗	static 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
579			✗	static 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
601			✗	static 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
615			✗	static 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
648			✗	static 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
682				static 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
695				static const luaL_Reg ll_funcs[] = {
696				{"require", ll_require},
697				{NULL, NULL}
698				};
699
700
701			✗	static 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				*/
726			✗	static 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
735			✗	LUAMOD_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
759