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1 | /* |
2 | ** $Id: loadlib.c,v 1.127 2015/11/23 11:30:45 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_PATH_VAR and LUA_CPATH_VAR are the names of the environment | |
29 | ** variables that Lua check to set its paths. | |
30 | */ | |
31 | #if !defined(LUA_PATH_VAR) | |
32 | #define LUA_PATH_VAR "LUA_PATH" | |
33 | #endif | |
34 | ||
35 | #if !defined(LUA_CPATH_VAR) | |
36 | #define LUA_CPATH_VAR "LUA_CPATH" | |
37 | #endif | |
38 | ||
39 | #define LUA_PATHSUFFIX "_" LUA_VERSION_MAJOR "_" LUA_VERSION_MINOR | |
40 | ||
41 | #define LUA_PATHVARVERSION LUA_PATH_VAR LUA_PATHSUFFIX | |
42 | #define LUA_CPATHVARVERSION LUA_CPATH_VAR LUA_PATHSUFFIX | |
43 | ||
44 | /* | |
45 | ** LUA_PATH_SEP is the character that separates templates in a path. | |
46 | ** LUA_PATH_MARK is the string that marks the substitution points in a | |
47 | ** template. | |
48 | ** LUA_EXEC_DIR in a Windows path is replaced by the executable's | |
49 | ** directory. | |
50 | ** LUA_IGMARK is a mark to ignore all before it when building the | |
51 | ** luaopen_ function name. | |
52 | */ | |
53 | #if !defined (LUA_PATH_SEP) | |
54 | #define LUA_PATH_SEP ";" | |
55 | #endif | |
56 | #if !defined (LUA_PATH_MARK) | |
57 | #define LUA_PATH_MARK "?" | |
58 | #endif | |
59 | #if !defined (LUA_EXEC_DIR) | |
60 | #define LUA_EXEC_DIR "!" | |
61 | #endif | |
62 | #if !defined (LUA_IGMARK) | |
63 | #define LUA_IGMARK "-" | |
64 | #endif | |
65 | ||
66 | ||
67 | /* | |
68 | ** LUA_CSUBSEP is the character that replaces dots in submodule names | |
69 | ** when searching for a C loader. | |
70 | ** LUA_LSUBSEP is the character that replaces dots in submodule names | |
71 | ** when searching for a Lua loader. | |
72 | */ | |
73 | #if !defined(LUA_CSUBSEP) | |
74 | #define LUA_CSUBSEP LUA_DIRSEP | |
75 | #endif | |
76 | ||
77 | #if !defined(LUA_LSUBSEP) | |
78 | #define LUA_LSUBSEP LUA_DIRSEP | |
79 | #endif | |
80 | ||
81 | ||
82 | /* prefix for open functions in C libraries */ | |
83 | #define LUA_POF "luaopen_" | |
84 | ||
85 | /* separator for open functions in C libraries */ | |
86 | #define LUA_OFSEP "_" | |
87 | ||
88 | ||
89 | /* | |
90 | ** unique key for table in the registry that keeps handles | |
91 | ** for all loaded C libraries | |
92 | */ | |
93 | static const int CLIBS = 0; | |
94 | ||
95 | #define LIB_FAIL "open" | |
96 | ||
97 | ||
98 | ||
99 | /* | |
100 | ** system-dependent functions | |
101 | */ | |
102 | ||
103 | /* | |
104 | ** unload library 'lib' | |
105 | */ | |
106 | static void lsys_unloadlib (void *lib); | |
107 | ||
108 | /* | |
109 | ** load C library in file 'path'. If 'seeglb', load with all names in | |
110 | ** the library global. | |
111 | ** Returns the library; in case of error, returns NULL plus an | |
112 | ** error string in the stack. | |
113 | */ | |
114 | static void *lsys_load (lua_State *L, const char *path, int seeglb); | |
115 | ||
116 | /* | |
117 | ** Try to find a function named 'sym' in library 'lib'. | |
118 | ** Returns the function; in case of error, returns NULL plus an | |
119 | ** error string in the stack. | |
120 | */ | |
121 | static lua_CFunction lsys_sym (lua_State *L, void *lib, const char *sym); | |
122 | ||
123 | /* | |
124 | ** {========================================================================= | |
125 | ** This determines the location of the executable for relative module loading | |
126 | ** Modified by the LuaDist project for UNIX platforms | |
127 | ** ========================================================================== | |
128 | */ | |
129 | #if defined(_WIN32) | |
130 | #include <windows.h> | |
131 | #define _PATH_MAX MAX_PATH | |
132 | #else | |
133 | #define _PATH_MAX PATH_MAX | |
134 | #endif | |
135 | ||
136 | #if defined (__CYGWIN__) | |
137 | #include <sys/cygwin.h> | |
138 | #endif | |
139 | ||
140 | #if defined(__linux__) || defined(__sun) | |
141 | #include <unistd.h> /* readlink */ | |
142 | #endif | |
143 | ||
144 | #if defined(__APPLE__) | |
145 | #include <sys/param.h> | |
146 | #include <mach-o/dyld.h> | |
147 | #endif | |
148 | ||
149 | #if defined(__FreeBSD__) | |
150 | #include <sys/types.h> | |
151 | #include <sys/sysctl.h> | |
152 | #endif | |
153 | ||
154 | static void setprogdir(lua_State *L) { | |
155 | char progdir[_PATH_MAX + 1]; | |
156 | char *lb; | |
157 | int nsize = sizeof(progdir)/sizeof(char); | |
158 | int n = 0; | |
159 | #if defined(__CYGWIN__) | |
160 | char win_buff[_PATH_MAX + 1]; | |
161 | GetModuleFileNameA(NULL, win_buff, nsize); | |
162 | cygwin_conv_path(CCP_WIN_A_TO_POSIX, win_buff, progdir, nsize); | |
163 | n = strlen(progdir); | |
164 | #elif defined(_WIN32) | |
165 | n = GetModuleFileNameA(NULL, progdir, nsize); | |
166 | #elif defined(__linux__) | |
167 | n = readlink("/proc/self/exe", progdir, nsize); | |
168 | if (n > 0) progdir[n] = 0; | |
169 | #elif defined(__sun) | |
170 | pid_t pid = getpid(); | |
171 | char linkname[256]; | |
172 | sprintf(linkname, "/proc/%d/path/a.out", pid); | |
173 | n = readlink(linkname, progdir, nsize); | |
174 | if (n > 0) progdir[n] = 0; | |
175 | #elif defined(__FreeBSD__) | |
176 | int mib[4]; | |
177 | mib[0] = CTL_KERN; | |
178 | mib[1] = KERN_PROC; | |
179 | mib[2] = KERN_PROC_PATHNAME; | |
180 | mib[3] = -1; | |
181 | size_t cb = nsize; | |
182 | sysctl(mib, 4, progdir, &cb, NULL, 0); | |
183 | n = cb; | |
184 | #elif defined(__BSD__) | |
185 | n = readlink("/proc/curproc/file", progdir, nsize); | |
186 | if (n > 0) progdir[n] = 0; | |
187 | #elif defined(__APPLE__) | |
188 | uint32_t nsize_apple = nsize; | |
189 | if (_NSGetExecutablePath(progdir, &nsize_apple) == 0) | |
190 | n = strlen(progdir); | |
191 | #else | |
192 | // FALLBACK | |
193 | // Use 'lsof' ... should work on most UNIX systems (incl. OSX) | |
194 | // lsof will list open files, this captures the 1st file listed (usually the executable) | |
195 | int pid; | |
196 | FILE* fd; | |
197 | char cmd[80]; | |
198 | pid = getpid(); | |
199 | ||
200 | sprintf(cmd, "lsof -p %d | awk '{if ($5==\"REG\") { print $9 ; exit}}' 2> /dev/null", pid); | |
201 | fd = popen(cmd, "r"); | |
202 | n = fread(progdir, 1, nsize, fd); | |
203 | pclose(fd); | |
204 | ||
205 | // remove newline | |
206 | if (n > 1) progdir[--n] = '\0'; | |
207 | #endif | |
208 | if (n == 0 || n == nsize || (lb = strrchr(progdir, (int)LUA_DIRSEP[0])) == NULL) | |
209 | luaL_error(L, "unable to get process executable path"); | |
210 | else { | |
211 | *lb = '\0'; | |
212 | ||
213 | // Replace the relative path placeholder | |
214 | luaL_gsub(L, lua_tostring(L, -1), LUA_EXEC_DIR, progdir); | |
215 | lua_remove(L, -2); | |
216 | } | |
217 | } | |
218 | ||
219 | #if defined(LUA_USE_DLOPEN) /* { */ | |
220 | /* | |
221 | ** {======================================================================== | |
222 | ** This is an implementation of loadlib based on the dlfcn interface. | |
223 | ** The dlfcn interface is available in Linux, SunOS, Solaris, IRIX, FreeBSD, | |
224 | ** NetBSD, AIX 4.2, HPUX 11, and probably most other Unix flavors, at least | |
225 | ** as an emulation layer on top of native functions. | |
226 | ** ========================================================================= | |
227 | */ | |
228 | ||
229 | #include <dlfcn.h> | |
230 | ||
231 | /* | |
232 | ** Macro to convert pointer-to-void* to pointer-to-function. This cast | |
233 | ** is undefined according to ISO C, but POSIX assumes that it works. | |
234 | ** (The '__extension__' in gnu compilers is only to avoid warnings.) | |
235 | */ | |
236 | #if defined(__GNUC__) | |
237 | #define cast_func(p) (__extension__ (lua_CFunction)(p)) | |
238 | #else | |
239 | #define cast_func(p) ((lua_CFunction)(p)) | |
240 | #endif | |
241 | ||
242 | ||
243 | static void lsys_unloadlib (void *lib) { | |
244 | dlclose(lib); | |
245 | } | |
246 | ||
247 | ||
248 | static void *lsys_load (lua_State *L, const char *path, int seeglb) { | |
249 | void *lib = dlopen(path, RTLD_NOW | (seeglb ? RTLD_GLOBAL : RTLD_LOCAL)); | |
250 | if (lib == NULL) lua_pushstring(L, dlerror()); | |
251 | return lib; | |
252 | } | |
253 | ||
254 | ||
255 | static lua_CFunction lsys_sym (lua_State *L, void *lib, const char *sym) { | |
256 | lua_CFunction f = cast_func(dlsym(lib, sym)); | |
257 | if (f == NULL) lua_pushstring(L, dlerror()); | |
258 | return f; | |
259 | } | |
260 | ||
261 | /* }====================================================== */ | |
262 | ||
263 | ||
264 | ||
265 | #elif defined(LUA_DL_DLL) /* }{ */ | |
266 | /* | |
267 | ** {====================================================================== | |
268 | ** This is an implementation of loadlib for Windows using native functions. | |
269 | ** ======================================================================= | |
270 | */ | |
271 | ||
272 | /* | |
273 | ** optional flags for LoadLibraryEx | |
274 | */ | |
275 | #if !defined(LUA_LLE_FLAGS) | |
276 | #define LUA_LLE_FLAGS 0 | |
277 | #endif | |
278 | ||
279 | static void pusherror (lua_State *L) { | |
280 | int error = GetLastError(); | |
281 | char buffer[128]; | |
282 | if (FormatMessageA(FORMAT_MESSAGE_IGNORE_INSERTS | FORMAT_MESSAGE_FROM_SYSTEM, | |
283 | NULL, error, 0, buffer, sizeof(buffer)/sizeof(char), NULL)) | |
284 | lua_pushstring(L, buffer); | |
285 | else | |
286 | lua_pushfstring(L, "system error %d\n", error); | |
287 | } | |
288 | ||
289 | static void lsys_unloadlib (void *lib) { | |
290 | FreeLibrary((HMODULE)lib); | |
291 | } | |
292 | ||
293 | ||
294 | static void *lsys_load (lua_State *L, const char *path, int seeglb) { | |
295 | HMODULE lib = LoadLibraryExA(path, NULL, LUA_LLE_FLAGS); | |
296 | (void)(seeglb); /* not used: symbols are 'global' by default */ | |
297 | if (lib == NULL) pusherror(L); | |
298 | return lib; | |
299 | } | |
300 | ||
301 | ||
302 | static lua_CFunction lsys_sym (lua_State *L, void *lib, const char *sym) { | |
303 | lua_CFunction f = (lua_CFunction)GetProcAddress((HMODULE)lib, sym); | |
304 | if (f == NULL) pusherror(L); | |
305 | return f; | |
306 | } | |
307 | ||
308 | /* }====================================================== */ | |
309 | ||
310 | ||
311 | #else /* }{ */ | |
312 | /* | |
313 | ** {====================================================== | |
314 | ** Fallback for other systems | |
315 | ** ======================================================= | |
316 | */ | |
317 | ||
318 | #undef LIB_FAIL | |
319 | #define LIB_FAIL "absent" | |
320 | ||
321 | ||
322 | #define DLMSG "dynamic libraries not enabled; check your Lua installation" | |
323 | ||
324 | ||
325 | static void lsys_unloadlib (void *lib) { | |
326 | (void)(lib); /* not used */ | |
327 | } | |
328 | ||
329 | ||
330 | static void *lsys_load (lua_State *L, const char *path, int seeglb) { | |
331 | (void)(path); (void)(seeglb); /* not used */ | |
332 | lua_pushliteral(L, DLMSG); | |
333 | return NULL; | |
334 | } | |
335 | ||
336 | ||
337 | static lua_CFunction lsys_sym (lua_State *L, void *lib, const char *sym) { | |
338 | (void)(lib); (void)(sym); /* not used */ | |
339 | lua_pushliteral(L, DLMSG); | |
340 | return NULL; | |
341 | } | |
342 | ||
343 | /* }====================================================== */ | |
344 | #endif /* } */ | |
345 | ||
346 | ||
347 | /* | |
348 | ** return registry.CLIBS[path] | |
349 | */ | |
350 | static void *checkclib (lua_State *L, const char *path) { | |
351 | void *plib; | |
352 | lua_rawgetp(L, LUA_REGISTRYINDEX, &CLIBS); | |
353 | lua_getfield(L, -1, path); | |
354 | plib = lua_touserdata(L, -1); /* plib = CLIBS[path] */ | |
355 | lua_pop(L, 2); /* pop CLIBS table and 'plib' */ | |
356 | return plib; | |
357 | } | |
358 | ||
359 | ||
360 | /* | |
361 | ** registry.CLIBS[path] = plib -- for queries | |
362 | ** registry.CLIBS[#CLIBS + 1] = plib -- also keep a list of all libraries | |
363 | */ | |
364 | static void addtoclib (lua_State *L, const char *path, void *plib) { | |
365 | lua_rawgetp(L, LUA_REGISTRYINDEX, &CLIBS); | |
366 | lua_pushlightuserdata(L, plib); | |
367 | lua_pushvalue(L, -1); | |
368 | lua_setfield(L, -3, path); /* CLIBS[path] = plib */ | |
369 | lua_rawseti(L, -2, luaL_len(L, -2) + 1); /* CLIBS[#CLIBS + 1] = plib */ | |
370 | lua_pop(L, 1); /* pop CLIBS table */ | |
371 | } | |
372 | ||
373 | ||
374 | /* | |
375 | ** __gc tag method for CLIBS table: calls 'lsys_unloadlib' for all lib | |
376 | ** handles in list CLIBS | |
377 | */ | |
378 | static int gctm (lua_State *L) { | |
379 | lua_Integer n = luaL_len(L, 1); | |
380 | for (; n >= 1; n--) { /* for each handle, in reverse order */ | |
381 | lua_rawgeti(L, 1, n); /* get handle CLIBS[n] */ | |
382 | lsys_unloadlib(lua_touserdata(L, -1)); | |
383 | lua_pop(L, 1); /* pop handle */ | |
384 | } | |
385 | return 0; | |
386 | } | |
387 | ||
388 | ||
389 | ||
390 | /* error codes for 'lookforfunc' */ | |
391 | #define ERRLIB 1 | |
392 | #define ERRFUNC 2 | |
393 | ||
394 | /* | |
395 | ** Look for a C function named 'sym' in a dynamically loaded library | |
396 | ** 'path'. | |
397 | ** First, check whether the library is already loaded; if not, try | |
398 | ** to load it. | |
399 | ** Then, if 'sym' is '*', return true (as library has been loaded). | |
400 | ** Otherwise, look for symbol 'sym' in the library and push a | |
401 | ** C function with that symbol. | |
402 | ** Return 0 and 'true' or a function in the stack; in case of | |
403 | ** errors, return an error code and an error message in the stack. | |
404 | */ | |
405 | static int lookforfunc (lua_State *L, const char *path, const char *sym) { | |
406 | void *reg = checkclib(L, path); /* check loaded C libraries */ | |
407 | if (reg == NULL) { /* must load library? */ | |
408 | reg = lsys_load(L, path, *sym == '*'); /* global symbols if 'sym'=='*' */ | |
409 | if (reg == NULL) return ERRLIB; /* unable to load library */ | |
410 | addtoclib(L, path, reg); | |
411 | } | |
412 | if (*sym == '*') { /* loading only library (no function)? */ | |
413 | lua_pushboolean(L, 1); /* return 'true' */ | |
414 | return 0; /* no errors */ | |
415 | } | |
416 | else { | |
417 | lua_CFunction f = lsys_sym(L, reg, sym); | |
418 | if (f == NULL) | |
419 | return ERRFUNC; /* unable to find function */ | |
420 | lua_pushcfunction(L, f); /* else create new function */ | |
421 | return 0; /* no errors */ | |
422 | } | |
423 | } | |
424 | ||
425 | ||
426 | static int ll_loadlib (lua_State *L) { | |
427 | const char *path = luaL_checkstring(L, 1); | |
428 | const char *init = luaL_checkstring(L, 2); | |
429 | int stat = lookforfunc(L, path, init); | |
430 | if (stat == 0) /* no errors? */ | |
431 | return 1; /* return the loaded function */ | |
432 | else { /* error; error message is on stack top */ | |
433 | lua_pushnil(L); | |
434 | lua_insert(L, -2); | |
435 | lua_pushstring(L, (stat == ERRLIB) ? LIB_FAIL : "init"); | |
436 | return 3; /* return nil, error message, and where */ | |
437 | } | |
438 | } | |
439 | ||
440 | ||
441 | ||
442 | /* | |
443 | ** {====================================================== | |
444 | ** 'require' function | |
445 | ** ======================================================= | |
446 | */ | |
447 | ||
448 | ||
449 | static int readable (const char *filename) { | |
450 | FILE *f = fopen(filename, "r"); /* try to open file */ | |
451 | if (f == NULL) return 0; /* open failed */ | |
452 | fclose(f); | |
453 | return 1; | |
454 | } | |
455 | ||
456 | ||
457 | static const char *pushnexttemplate (lua_State *L, const char *path) { | |
458 | const char *l; | |
459 | while (*path == *LUA_PATH_SEP) path++; /* skip separators */ | |
460 | if (*path == '\0') return NULL; /* no more templates */ | |
461 | l = strchr(path, *LUA_PATH_SEP); /* find next separator */ | |
462 | if (l == NULL) l = path + strlen(path); | |
463 | lua_pushlstring(L, path, l - path); /* template */ | |
464 | return l; | |
465 | } | |
466 | ||
467 | ||
468 | static const char *searchpath (lua_State *L, const char *name, | |
469 | const char *path, | |
470 | const char *sep, | |
471 | const char *dirsep) { | |
472 | luaL_Buffer msg; /* to build error message */ | |
473 | luaL_buffinit(L, &msg); | |
474 | if (*sep != '\0') /* non-empty separator? */ | |
475 | name = luaL_gsub(L, name, sep, dirsep); /* replace it by 'dirsep' */ | |
476 | while ((path = pushnexttemplate(L, path)) != NULL) { | |
477 | const char *filename = luaL_gsub(L, lua_tostring(L, -1), | |
478 | LUA_PATH_MARK, name); | |
479 | lua_remove(L, -2); /* remove path template */ | |
480 | if (readable(filename)) /* does file exist and is readable? */ | |
481 | return filename; /* return that file name */ | |
482 | lua_pushfstring(L, "\n\tno file '%s'", filename); | |
483 | lua_remove(L, -2); /* remove file name */ | |
484 | luaL_addvalue(&msg); /* concatenate error msg. entry */ | |
485 | } | |
486 | luaL_pushresult(&msg); /* create error message */ | |
487 | return NULL; /* not found */ | |
488 | } | |
489 | ||
490 | ||
491 | static int ll_searchpath (lua_State *L) { | |
492 | const char *f = searchpath(L, luaL_checkstring(L, 1), | |
493 | luaL_checkstring(L, 2), | |
494 | luaL_optstring(L, 3, "."), | |
495 | luaL_optstring(L, 4, LUA_DIRSEP)); | |
496 | if (f != NULL) return 1; | |
497 | else { /* error message is on top of the stack */ | |
498 | lua_pushnil(L); | |
499 | lua_insert(L, -2); | |
500 | return 2; /* return nil + error message */ | |
501 | } | |
502 | } | |
503 | ||
504 | ||
505 | static const char *findfile (lua_State *L, const char *name, | |
506 | const char *pname, | |
507 | const char *dirsep) { | |
508 | const char *path; | |
509 | lua_getfield(L, lua_upvalueindex(1), pname); | |
510 | path = lua_tostring(L, -1); | |
511 | if (path == NULL) | |
512 | luaL_error(L, "'package.%s' must be a string", pname); | |
513 | return searchpath(L, name, path, ".", dirsep); | |
514 | } | |
515 | ||
516 | ||
517 | static int checkload (lua_State *L, int stat, const char *filename) { | |
518 | if (stat) { /* module loaded successfully? */ | |
519 | lua_pushstring(L, filename); /* will be 2nd argument to module */ | |
520 | return 2; /* return open function and file name */ | |
521 | } | |
522 | else | |
523 | return luaL_error(L, "error loading module '%s' from file '%s':\n\t%s", | |
524 | lua_tostring(L, 1), filename, lua_tostring(L, -1)); | |
525 | } | |
526 | ||
527 | ||
528 | static int searcher_Lua (lua_State *L) { | |
529 | const char *filename; | |
530 | const char *name = luaL_checkstring(L, 1); | |
531 | filename = findfile(L, name, "path", LUA_LSUBSEP); | |
532 | if (filename == NULL) return 1; /* module not found in this path */ | |
533 | return checkload(L, (luaL_loadfile(L, filename) == LUA_OK), filename); | |
534 | } | |
535 | ||
536 | ||
537 | /* | |
538 | ** Try to find a load function for module 'modname' at file 'filename'. | |
539 | ** First, change '.' to '_' in 'modname'; then, if 'modname' has | |
540 | ** the form X-Y (that is, it has an "ignore mark"), build a function | |
541 | ** name "luaopen_X" and look for it. (For compatibility, if that | |
542 | ** fails, it also tries "luaopen_Y".) If there is no ignore mark, | |
543 | ** look for a function named "luaopen_modname". | |
544 | */ | |
545 | static int loadfunc (lua_State *L, const char *filename, const char *modname) { | |
546 | const char *openfunc; | |
547 | const char *mark; | |
548 | modname = luaL_gsub(L, modname, ".", LUA_OFSEP); | |
549 | mark = strchr(modname, *LUA_IGMARK); | |
550 | if (mark) { | |
551 | int stat; | |
552 | openfunc = lua_pushlstring(L, modname, mark - modname); | |
553 | openfunc = lua_pushfstring(L, LUA_POF"%s", openfunc); | |
554 | stat = lookforfunc(L, filename, openfunc); | |
555 | if (stat != ERRFUNC) return stat; | |
556 | modname = mark + 1; /* else go ahead and try old-style name */ | |
557 | } | |
558 | openfunc = lua_pushfstring(L, LUA_POF"%s", modname); | |
559 | return lookforfunc(L, filename, openfunc); | |
560 | } | |
561 | ||
562 | ||
563 | static int searcher_C (lua_State *L) { | |
564 | const char *name = luaL_checkstring(L, 1); | |
565 | const char *filename = findfile(L, name, "cpath", LUA_CSUBSEP); | |
566 | if (filename == NULL) return 1; /* module not found in this path */ | |
567 | return checkload(L, (loadfunc(L, filename, name) == 0), filename); | |
568 | } | |
569 | ||
570 | ||
571 | static int searcher_Croot (lua_State *L) { | |
572 | const char *filename; | |
573 | const char *name = luaL_checkstring(L, 1); | |
574 | const char *p = strchr(name, '.'); | |
575 | int stat; | |
576 | if (p == NULL) return 0; /* is root */ | |
577 | lua_pushlstring(L, name, p - name); | |
578 | filename = findfile(L, lua_tostring(L, -1), "cpath", LUA_CSUBSEP); | |
579 | if (filename == NULL) return 1; /* root not found */ | |
580 | if ((stat = loadfunc(L, filename, name)) != 0) { | |
581 | if (stat != ERRFUNC) | |
582 | return checkload(L, 0, filename); /* real error */ | |
583 | else { /* open function not found */ | |
584 | lua_pushfstring(L, "\n\tno module '%s' in file '%s'", name, filename); | |
585 | return 1; | |
586 | } | |
587 | } | |
588 | lua_pushstring(L, filename); /* will be 2nd argument to module */ | |
589 | return 2; | |
590 | } | |
591 | ||
592 | ||
593 | static int searcher_preload (lua_State *L) { | |
594 | const char *name = luaL_checkstring(L, 1); | |
595 | lua_getfield(L, LUA_REGISTRYINDEX, "_PRELOAD"); | |
596 | if (lua_getfield(L, -1, name) == LUA_TNIL) /* not found? */ | |
597 | lua_pushfstring(L, "\n\tno field package.preload['%s']", name); | |
598 | return 1; | |
599 | } | |
600 | ||
601 | ||
602 | static void findloader (lua_State *L, const char *name) { | |
603 | int i; | |
604 | luaL_Buffer msg; /* to build error message */ | |
605 | luaL_buffinit(L, &msg); | |
606 | /* push 'package.searchers' to index 3 in the stack */ | |
607 | if (lua_getfield(L, lua_upvalueindex(1), "searchers") != LUA_TTABLE) | |
608 | luaL_error(L, "'package.searchers' must be a table"); | |
609 | /* iterate over available searchers to find a loader */ | |
610 | for (i = 1; ; i++) { | |
611 | if (lua_rawgeti(L, 3, i) == LUA_TNIL) { /* no more searchers? */ | |
612 | lua_pop(L, 1); /* remove nil */ | |
613 | luaL_pushresult(&msg); /* create error message */ | |
614 | luaL_error(L, "module '%s' not found:%s", name, lua_tostring(L, -1)); | |
615 | } | |
616 | lua_pushstring(L, name); | |
617 | lua_call(L, 1, 2); /* call it */ | |
618 | if (lua_isfunction(L, -2)) /* did it find a loader? */ | |
619 | return; /* module loader found */ | |
620 | else if (lua_isstring(L, -2)) { /* searcher returned error message? */ | |
621 | lua_pop(L, 1); /* remove extra return */ | |
622 | luaL_addvalue(&msg); /* concatenate error message */ | |
623 | } | |
624 | else | |
625 | lua_pop(L, 2); /* remove both returns */ | |
626 | } | |
627 | } | |
628 | ||
629 | ||
630 | static int ll_require (lua_State *L) { | |
631 | const char *name = luaL_checkstring(L, 1); | |
632 | lua_settop(L, 1); /* _LOADED table will be at index 2 */ | |
633 | lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED"); | |
634 | lua_getfield(L, 2, name); /* _LOADED[name] */ | |
635 | if (lua_toboolean(L, -1)) /* is it there? */ | |
636 | return 1; /* package is already loaded */ | |
637 | /* else must load package */ | |
638 | lua_pop(L, 1); /* remove 'getfield' result */ | |
639 | findloader(L, name); | |
640 | lua_pushstring(L, name); /* pass name as argument to module loader */ | |
641 | lua_insert(L, -2); /* name is 1st argument (before search data) */ | |
642 | lua_call(L, 2, 1); /* run loader to load module */ | |
643 | if (!lua_isnil(L, -1)) /* non-nil return? */ | |
644 | lua_setfield(L, 2, name); /* _LOADED[name] = returned value */ | |
645 | if (lua_getfield(L, 2, name) == LUA_TNIL) { /* module set no value? */ | |
646 | lua_pushboolean(L, 1); /* use true as result */ | |
647 | lua_pushvalue(L, -1); /* extra copy to be returned */ | |
648 | lua_setfield(L, 2, name); /* _LOADED[name] = true */ | |
649 | } | |
650 | return 1; | |
651 | } | |
652 | ||
653 | /* }====================================================== */ | |
654 | ||
655 | ||
656 | ||
657 | /* | |
658 | ** {====================================================== | |
659 | ** 'module' function | |
660 | ** ======================================================= | |
661 | */ | |
662 | #if defined(LUA_COMPAT_MODULE) | |
663 | ||
664 | /* | |
665 | ** changes the environment variable of calling function | |
666 | */ | |
667 | static void set_env (lua_State *L) { | |
668 | lua_Debug ar; | |
669 | if (lua_getstack(L, 1, &ar) == 0 || | |
670 | lua_getinfo(L, "f", &ar) == 0 || /* get calling function */ | |
671 | lua_iscfunction(L, -1)) | |
672 | luaL_error(L, "'module' not called from a Lua function"); | |
673 | lua_pushvalue(L, -2); /* copy new environment table to top */ | |
674 | lua_setupvalue(L, -2, 1); | |
675 | lua_pop(L, 1); /* remove function */ | |
676 | } | |
677 | ||
678 | ||
679 | static void dooptions (lua_State *L, int n) { | |
680 | int i; | |
681 | for (i = 2; i <= n; i++) { | |
682 | if (lua_isfunction(L, i)) { /* avoid 'calling' extra info. */ | |
683 | lua_pushvalue(L, i); /* get option (a function) */ | |
684 | lua_pushvalue(L, -2); /* module */ | |
685 | lua_call(L, 1, 0); | |
686 | } | |
687 | } | |
688 | } | |
689 | ||
690 | ||
691 | static void modinit (lua_State *L, const char *modname) { | |
692 | const char *dot; | |
693 | lua_pushvalue(L, -1); | |
694 | lua_setfield(L, -2, "_M"); /* module._M = module */ | |
695 | lua_pushstring(L, modname); | |
696 | lua_setfield(L, -2, "_NAME"); | |
697 | dot = strrchr(modname, '.'); /* look for last dot in module name */ | |
698 | if (dot == NULL) dot = modname; | |
699 | else dot++; | |
700 | /* set _PACKAGE as package name (full module name minus last part) */ | |
701 | lua_pushlstring(L, modname, dot - modname); | |
702 | lua_setfield(L, -2, "_PACKAGE"); | |
703 | } | |
704 | ||
705 | ||
706 | static int ll_module (lua_State *L) { | |
707 | const char *modname = luaL_checkstring(L, 1); | |
708 | int lastarg = lua_gettop(L); /* last parameter */ | |
709 | luaL_pushmodule(L, modname, 1); /* get/create module table */ | |
710 | /* check whether table already has a _NAME field */ | |
711 | if (lua_getfield(L, -1, "_NAME") != LUA_TNIL) | |
712 | lua_pop(L, 1); /* table is an initialized module */ | |
713 | else { /* no; initialize it */ | |
714 | lua_pop(L, 1); | |
715 | modinit(L, modname); | |
716 | } | |
717 | lua_pushvalue(L, -1); | |
718 | set_env(L); | |
719 | dooptions(L, lastarg); | |
720 | return 1; | |
721 | } | |
722 | ||
723 | ||
724 | static int ll_seeall (lua_State *L) { | |
725 | luaL_checktype(L, 1, LUA_TTABLE); | |
726 | if (!lua_getmetatable(L, 1)) { | |
727 | lua_createtable(L, 0, 1); /* create new metatable */ | |
728 | lua_pushvalue(L, -1); | |
729 | lua_setmetatable(L, 1); | |
730 | } | |
731 | lua_pushglobaltable(L); | |
732 | lua_setfield(L, -2, "__index"); /* mt.__index = _G */ | |
733 | return 0; | |
734 | } | |
735 | ||
736 | #endif | |
737 | /* }====================================================== */ | |
738 | ||
739 | ||
740 | ||
741 | /* auxiliary mark (for internal use) */ | |
742 | #define AUXMARK "\1" | |
743 | ||
744 | ||
745 | /* | |
746 | ** return registry.LUA_NOENV as a boolean | |
747 | */ | |
748 | static int noenv (lua_State *L) { | |
749 | int b; | |
750 | lua_getfield(L, LUA_REGISTRYINDEX, "LUA_NOENV"); | |
751 | b = lua_toboolean(L, -1); | |
752 | lua_pop(L, 1); /* remove value */ | |
753 | return b; | |
754 | } | |
755 | ||
756 | ||
757 | static void setpath (lua_State *L, const char *fieldname, const char *envname1, | |
758 | const char *envname2, const char *def) { | |
759 | const char *path = getenv(envname1); | |
760 | if (path == NULL) /* no environment variable? */ | |
761 | path = getenv(envname2); /* try alternative name */ | |
762 | if (path == NULL || noenv(L)) /* no environment variable? */ | |
763 | lua_pushstring(L, def); /* use default */ | |
764 | else { | |
765 | /* replace ";;" by ";AUXMARK;" and then AUXMARK by default path */ | |
766 | path = luaL_gsub(L, path, LUA_PATH_SEP LUA_PATH_SEP, | |
767 | LUA_PATH_SEP AUXMARK LUA_PATH_SEP); | |
768 | luaL_gsub(L, path, AUXMARK, def); | |
769 | lua_remove(L, -2); | |
770 | } | |
771 | setprogdir(L); | |
772 | lua_setfield(L, -2, fieldname); | |
773 | } | |
774 | ||
775 | ||
776 | static const luaL_Reg pk_funcs[] = { | |
777 | {"loadlib", ll_loadlib}, | |
778 | {"searchpath", ll_searchpath}, | |
779 | #if defined(LUA_COMPAT_MODULE) | |
780 | {"seeall", ll_seeall}, | |
781 | #endif | |
782 | /* placeholders */ | |
783 | {"preload", NULL}, | |
784 | {"cpath", NULL}, | |
785 | {"path", NULL}, | |
786 | {"searchers", NULL}, | |
787 | {"loaded", NULL}, | |
788 | {NULL, NULL} | |
789 | }; | |
790 | ||
791 | ||
792 | static const luaL_Reg ll_funcs[] = { | |
793 | #if defined(LUA_COMPAT_MODULE) | |
794 | {"module", ll_module}, | |
795 | #endif | |
796 | {"require", ll_require}, | |
797 | {NULL, NULL} | |
798 | }; | |
799 | ||
800 | ||
801 | static void createsearcherstable (lua_State *L) { | |
802 | static const lua_CFunction searchers[] = | |
803 | {searcher_preload, searcher_Lua, searcher_C, searcher_Croot, NULL}; | |
804 | int i; | |
805 | /* create 'searchers' table */ | |
806 | lua_createtable(L, sizeof(searchers)/sizeof(searchers[0]) - 1, 0); | |
807 | /* fill it with predefined searchers */ | |
808 | for (i=0; searchers[i] != NULL; i++) { | |
809 | lua_pushvalue(L, -2); /* set 'package' as upvalue for all searchers */ | |
810 | lua_pushcclosure(L, searchers[i], 1); | |
811 | lua_rawseti(L, -2, i+1); | |
812 | } | |
813 | #if defined(LUA_COMPAT_LOADERS) | |
814 | lua_pushvalue(L, -1); /* make a copy of 'searchers' table */ | |
815 | lua_setfield(L, -3, "loaders"); /* put it in field 'loaders' */ | |
816 | #endif | |
817 | lua_setfield(L, -2, "searchers"); /* put it in field 'searchers' */ | |
818 | } | |
819 | ||
820 | ||
821 | /* | |
822 | ** create table CLIBS to keep track of loaded C libraries, | |
823 | ** setting a finalizer to close all libraries when closing state. | |
824 | */ | |
825 | static void createclibstable (lua_State *L) { | |
826 | lua_newtable(L); /* create CLIBS table */ | |
827 | lua_createtable(L, 0, 1); /* create metatable for CLIBS */ | |
828 | lua_pushcfunction(L, gctm); | |
829 | lua_setfield(L, -2, "__gc"); /* set finalizer for CLIBS table */ | |
830 | lua_setmetatable(L, -2); | |
831 | lua_rawsetp(L, LUA_REGISTRYINDEX, &CLIBS); /* set CLIBS table in registry */ | |
832 | } | |
833 | ||
834 | ||
835 | LUAMOD_API int luaopen_package (lua_State *L) { | |
836 | createclibstable(L); | |
837 | luaL_newlib(L, pk_funcs); /* create 'package' table */ | |
838 | createsearcherstable(L); | |
839 | /* set field 'path' */ | |
840 | setpath(L, "path", LUA_PATHVARVERSION, LUA_PATH_VAR, LUA_PATH_DEFAULT); | |
841 | /* set field 'cpath' */ | |
842 | setpath(L, "cpath", LUA_CPATHVARVERSION, LUA_CPATH_VAR, LUA_CPATH_DEFAULT); | |
843 | /* store config information */ | |
844 | lua_pushliteral(L, LUA_DIRSEP "\n" LUA_PATH_SEP "\n" LUA_PATH_MARK "\n" | |
845 | LUA_EXEC_DIR "\n" LUA_IGMARK "\n"); | |
846 | lua_setfield(L, -2, "config"); | |
847 | /* set field 'loaded' */ | |
848 | luaL_getsubtable(L, LUA_REGISTRYINDEX, "_LOADED"); | |
849 | lua_setfield(L, -2, "loaded"); | |
850 | /* set field 'preload' */ | |
851 | luaL_getsubtable(L, LUA_REGISTRYINDEX, "_PRELOAD"); | |
852 | lua_setfield(L, -2, "preload"); | |
853 | lua_pushglobaltable(L); | |
854 | lua_pushvalue(L, -2); /* set 'package' as upvalue for next lib */ | |
855 | luaL_setfuncs(L, ll_funcs, 1); /* open lib into global table */ | |
856 | lua_pop(L, 1); /* pop global table */ | |
857 | return 1; /* return 'package' table */ | |
858 | } | |
859 |