release.sh changes & fixes
[minix3.git] / external / mit / lua / dist / src / loadlib.c
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1 /* $NetBSD: loadlib.c,v 1.1.1.2 2012/03/15 00:08:12 alnsn Exp $ */
3 /*
4 ** $Id: loadlib.c,v 1.1.1.2 2012/03/15 00:08:12 alnsn Exp $
5 ** Dynamic library loader for Lua
6 ** See Copyright Notice in lua.h
7 **
8 ** This module contains an implementation of loadlib for Unix systems
9 ** that have dlfcn, an implementation for Darwin (Mac OS X), an
10 ** implementation for Windows, and a stub for other systems.
14 #include <stdlib.h>
15 #include <string.h>
18 #define loadlib_c
19 #define LUA_LIB
21 #include "lua.h"
23 #include "lauxlib.h"
24 #include "lualib.h"
27 /* prefix for open functions in C libraries */
28 #define LUA_POF "luaopen_"
30 /* separator for open functions in C libraries */
31 #define LUA_OFSEP "_"
34 #define LIBPREFIX "LOADLIB: "
36 #define POF LUA_POF
37 #define LIB_FAIL "open"
40 /* error codes for ll_loadfunc */
41 #define ERRLIB 1
42 #define ERRFUNC 2
44 #define setprogdir(L) ((void)0)
47 static void ll_unloadlib (void *lib);
48 static void *ll_load (lua_State *L, const char *path);
49 static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym);
53 #if defined(LUA_DL_DLOPEN)
55 ** {========================================================================
56 ** This is an implementation of loadlib based on the dlfcn interface.
57 ** The dlfcn interface is available in Linux, SunOS, Solaris, IRIX, FreeBSD,
58 ** NetBSD, AIX 4.2, HPUX 11, and probably most other Unix flavors, at least
59 ** as an emulation layer on top of native functions.
60 ** =========================================================================
63 #include <dlfcn.h>
65 static void ll_unloadlib (void *lib) {
66 dlclose(lib);
70 static void *ll_load (lua_State *L, const char *path) {
71 void *lib = dlopen(path, RTLD_NOW);
72 if (lib == NULL) lua_pushstring(L, dlerror());
73 return lib;
77 static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
78 lua_CFunction f = (lua_CFunction)dlsym(lib, sym);
79 if (f == NULL) lua_pushstring(L, dlerror());
80 return f;
83 /* }====================================================== */
87 #elif defined(LUA_DL_DLL)
89 ** {======================================================================
90 ** This is an implementation of loadlib for Windows using native functions.
91 ** =======================================================================
94 #include <windows.h>
97 #undef setprogdir
99 static void setprogdir (lua_State *L) {
100 char buff[MAX_PATH + 1];
101 char *lb;
102 DWORD nsize = sizeof(buff)/sizeof(char);
103 DWORD n = GetModuleFileNameA(NULL, buff, nsize);
104 if (n == 0 || n == nsize || (lb = strrchr(buff, '\\')) == NULL)
105 luaL_error(L, "unable to get ModuleFileName");
106 else {
107 *lb = '\0';
108 luaL_gsub(L, lua_tostring(L, -1), LUA_EXECDIR, buff);
109 lua_remove(L, -2); /* remove original string */
114 static void pusherror (lua_State *L) {
115 int error = GetLastError();
116 char buffer[128];
117 if (FormatMessageA(FORMAT_MESSAGE_IGNORE_INSERTS | FORMAT_MESSAGE_FROM_SYSTEM,
118 NULL, error, 0, buffer, sizeof(buffer), NULL))
119 lua_pushstring(L, buffer);
120 else
121 lua_pushfstring(L, "system error %d\n", error);
124 static void ll_unloadlib (void *lib) {
125 FreeLibrary((HINSTANCE)lib);
129 static void *ll_load (lua_State *L, const char *path) {
130 HINSTANCE lib = LoadLibraryA(path);
131 if (lib == NULL) pusherror(L);
132 return lib;
136 static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
137 lua_CFunction f = (lua_CFunction)GetProcAddress((HINSTANCE)lib, sym);
138 if (f == NULL) pusherror(L);
139 return f;
142 /* }====================================================== */
146 #elif defined(LUA_DL_DYLD)
148 ** {======================================================================
149 ** Native Mac OS X / Darwin Implementation
150 ** =======================================================================
153 #include <mach-o/dyld.h>
156 /* Mac appends a `_' before C function names */
157 #undef POF
158 #define POF "_" LUA_POF
161 static void pusherror (lua_State *L) {
162 const char *err_str;
163 const char *err_file;
164 NSLinkEditErrors err;
165 int err_num;
166 NSLinkEditError(&err, &err_num, &err_file, &err_str);
167 lua_pushstring(L, err_str);
171 static const char *errorfromcode (NSObjectFileImageReturnCode ret) {
172 switch (ret) {
173 case NSObjectFileImageInappropriateFile:
174 return "file is not a bundle";
175 case NSObjectFileImageArch:
176 return "library is for wrong CPU type";
177 case NSObjectFileImageFormat:
178 return "bad format";
179 case NSObjectFileImageAccess:
180 return "cannot access file";
181 case NSObjectFileImageFailure:
182 default:
183 return "unable to load library";
188 static void ll_unloadlib (void *lib) {
189 NSUnLinkModule((NSModule)lib, NSUNLINKMODULE_OPTION_RESET_LAZY_REFERENCES);
193 static void *ll_load (lua_State *L, const char *path) {
194 NSObjectFileImage img;
195 NSObjectFileImageReturnCode ret;
196 /* this would be a rare case, but prevents crashing if it happens */
197 if(!_dyld_present()) {
198 lua_pushliteral(L, "dyld not present");
199 return NULL;
201 ret = NSCreateObjectFileImageFromFile(path, &img);
202 if (ret == NSObjectFileImageSuccess) {
203 NSModule mod = NSLinkModule(img, path, NSLINKMODULE_OPTION_PRIVATE |
204 NSLINKMODULE_OPTION_RETURN_ON_ERROR);
205 NSDestroyObjectFileImage(img);
206 if (mod == NULL) pusherror(L);
207 return mod;
209 lua_pushstring(L, errorfromcode(ret));
210 return NULL;
214 static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
215 NSSymbol nss = NSLookupSymbolInModule((NSModule)lib, sym);
216 if (nss == NULL) {
217 lua_pushfstring(L, "symbol " LUA_QS " not found", sym);
218 return NULL;
220 return (lua_CFunction)NSAddressOfSymbol(nss);
223 /* }====================================================== */
227 #else
229 ** {======================================================
230 ** Fallback for other systems
231 ** =======================================================
234 #undef LIB_FAIL
235 #define LIB_FAIL "absent"
238 #define DLMSG "dynamic libraries not enabled; check your Lua installation"
241 static void ll_unloadlib (void *lib) {
242 (void)lib; /* to avoid warnings */
246 static void *ll_load (lua_State *L, const char *path) {
247 (void)path; /* to avoid warnings */
248 lua_pushliteral(L, DLMSG);
249 return NULL;
253 static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
254 (void)lib; (void)sym; /* to avoid warnings */
255 lua_pushliteral(L, DLMSG);
256 return NULL;
259 /* }====================================================== */
260 #endif
264 static void **ll_register (lua_State *L, const char *path) {
265 void **plib;
266 lua_pushfstring(L, "%s%s", LIBPREFIX, path);
267 lua_gettable(L, LUA_REGISTRYINDEX); /* check library in registry? */
268 if (!lua_isnil(L, -1)) /* is there an entry? */
269 plib = (void **)lua_touserdata(L, -1);
270 else { /* no entry yet; create one */
271 lua_pop(L, 1);
272 plib = (void **)lua_newuserdata(L, sizeof(const void *));
273 *plib = NULL;
274 luaL_getmetatable(L, "_LOADLIB");
275 lua_setmetatable(L, -2);
276 lua_pushfstring(L, "%s%s", LIBPREFIX, path);
277 lua_pushvalue(L, -2);
278 lua_settable(L, LUA_REGISTRYINDEX);
280 return plib;
285 ** __gc tag method: calls library's `ll_unloadlib' function with the lib
286 ** handle
288 static int gctm (lua_State *L) {
289 void **lib = (void **)luaL_checkudata(L, 1, "_LOADLIB");
290 if (*lib) ll_unloadlib(*lib);
291 *lib = NULL; /* mark library as closed */
292 return 0;
296 static int ll_loadfunc (lua_State *L, const char *path, const char *sym) {
297 void **reg = ll_register(L, path);
298 if (*reg == NULL) *reg = ll_load(L, path);
299 if (*reg == NULL)
300 return ERRLIB; /* unable to load library */
301 else {
302 lua_CFunction f = ll_sym(L, *reg, sym);
303 if (f == NULL)
304 return ERRFUNC; /* unable to find function */
305 lua_pushcfunction(L, f);
306 return 0; /* return function */
311 static int ll_loadlib (lua_State *L) {
312 const char *path = luaL_checkstring(L, 1);
313 const char *init = luaL_checkstring(L, 2);
314 int stat = ll_loadfunc(L, path, init);
315 if (stat == 0) /* no errors? */
316 return 1; /* return the loaded function */
317 else { /* error; error message is on stack top */
318 lua_pushnil(L);
319 lua_insert(L, -2);
320 lua_pushstring(L, (stat == ERRLIB) ? LIB_FAIL : "init");
321 return 3; /* return nil, error message, and where */
328 ** {======================================================
329 ** 'require' function
330 ** =======================================================
334 static int readable (const char *filename) {
335 FILE *f = fopen(filename, "r"); /* try to open file */
336 if (f == NULL) return 0; /* open failed */
337 fclose(f);
338 return 1;
342 static const char *pushnexttemplate (lua_State *L, const char *path) {
343 const char *l;
344 while (*path == *LUA_PATHSEP) path++; /* skip separators */
345 if (*path == '\0') return NULL; /* no more templates */
346 l = strchr(path, *LUA_PATHSEP); /* find next separator */
347 if (l == NULL) l = path + strlen(path);
348 lua_pushlstring(L, path, l - path); /* template */
349 return l;
353 static const char *findfile (lua_State *L, const char *name,
354 const char *pname) {
355 const char *path;
356 name = luaL_gsub(L, name, ".", LUA_DIRSEP);
357 lua_getfield(L, LUA_ENVIRONINDEX, pname);
358 path = lua_tostring(L, -1);
359 if (path == NULL)
360 luaL_error(L, LUA_QL("package.%s") " must be a string", pname);
361 lua_pushliteral(L, ""); /* error accumulator */
362 while ((path = pushnexttemplate(L, path)) != NULL) {
363 const char *filename;
364 filename = luaL_gsub(L, lua_tostring(L, -1), LUA_PATH_MARK, name);
365 lua_remove(L, -2); /* remove path template */
366 if (readable(filename)) /* does file exist and is readable? */
367 return filename; /* return that file name */
368 lua_pushfstring(L, "\n\tno file " LUA_QS, filename);
369 lua_remove(L, -2); /* remove file name */
370 lua_concat(L, 2); /* add entry to possible error message */
372 return NULL; /* not found */
376 static void loaderror (lua_State *L, const char *filename) {
377 luaL_error(L, "error loading module " LUA_QS " from file " LUA_QS ":\n\t%s",
378 lua_tostring(L, 1), filename, lua_tostring(L, -1));
382 static int loader_Lua (lua_State *L) {
383 const char *filename;
384 const char *name = luaL_checkstring(L, 1);
385 filename = findfile(L, name, "path");
386 if (filename == NULL) return 1; /* library not found in this path */
387 if (luaL_loadfile(L, filename) != 0)
388 loaderror(L, filename);
389 return 1; /* library loaded successfully */
393 static const char *mkfuncname (lua_State *L, const char *modname) {
394 const char *funcname;
395 const char *mark = strchr(modname, *LUA_IGMARK);
396 if (mark) modname = mark + 1;
397 funcname = luaL_gsub(L, modname, ".", LUA_OFSEP);
398 funcname = lua_pushfstring(L, POF"%s", funcname);
399 lua_remove(L, -2); /* remove 'gsub' result */
400 return funcname;
404 static int loader_C (lua_State *L) {
405 const char *funcname;
406 const char *name = luaL_checkstring(L, 1);
407 const char *filename = findfile(L, name, "cpath");
408 if (filename == NULL) return 1; /* library not found in this path */
409 funcname = mkfuncname(L, name);
410 if (ll_loadfunc(L, filename, funcname) != 0)
411 loaderror(L, filename);
412 return 1; /* library loaded successfully */
416 static int loader_Croot (lua_State *L) {
417 const char *funcname;
418 const char *filename;
419 const char *name = luaL_checkstring(L, 1);
420 const char *p = strchr(name, '.');
421 int stat;
422 if (p == NULL) return 0; /* is root */
423 lua_pushlstring(L, name, p - name);
424 filename = findfile(L, lua_tostring(L, -1), "cpath");
425 if (filename == NULL) return 1; /* root not found */
426 funcname = mkfuncname(L, name);
427 if ((stat = ll_loadfunc(L, filename, funcname)) != 0) {
428 if (stat != ERRFUNC) loaderror(L, filename); /* real error */
429 lua_pushfstring(L, "\n\tno module " LUA_QS " in file " LUA_QS,
430 name, filename);
431 return 1; /* function not found */
433 return 1;
437 static int loader_preload (lua_State *L) {
438 const char *name = luaL_checkstring(L, 1);
439 lua_getfield(L, LUA_ENVIRONINDEX, "preload");
440 if (!lua_istable(L, -1))
441 luaL_error(L, LUA_QL("package.preload") " must be a table");
442 lua_getfield(L, -1, name);
443 if (lua_isnil(L, -1)) /* not found? */
444 lua_pushfstring(L, "\n\tno field package.preload['%s']", name);
445 return 1;
449 static const int sentinel_ = 0;
450 #define sentinel ((void *)&sentinel_)
453 static int ll_require (lua_State *L) {
454 const char *name = luaL_checkstring(L, 1);
455 int i;
456 lua_settop(L, 1); /* _LOADED table will be at index 2 */
457 lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
458 lua_getfield(L, 2, name);
459 if (lua_toboolean(L, -1)) { /* is it there? */
460 if (lua_touserdata(L, -1) == sentinel) /* check loops */
461 luaL_error(L, "loop or previous error loading module " LUA_QS, name);
462 return 1; /* package is already loaded */
464 /* else must load it; iterate over available loaders */
465 lua_getfield(L, LUA_ENVIRONINDEX, "loaders");
466 if (!lua_istable(L, -1))
467 luaL_error(L, LUA_QL("package.loaders") " must be a table");
468 lua_pushliteral(L, ""); /* error message accumulator */
469 for (i=1; ; i++) {
470 lua_rawgeti(L, -2, i); /* get a loader */
471 if (lua_isnil(L, -1))
472 luaL_error(L, "module " LUA_QS " not found:%s",
473 name, lua_tostring(L, -2));
474 lua_pushstring(L, name);
475 lua_call(L, 1, 1); /* call it */
476 if (lua_isfunction(L, -1)) /* did it find module? */
477 break; /* module loaded successfully */
478 else if (lua_isstring(L, -1)) /* loader returned error message? */
479 lua_concat(L, 2); /* accumulate it */
480 else
481 lua_pop(L, 1);
483 lua_pushlightuserdata(L, sentinel);
484 lua_setfield(L, 2, name); /* _LOADED[name] = sentinel */
485 lua_pushstring(L, name); /* pass name as argument to module */
486 lua_call(L, 1, 1); /* run loaded module */
487 if (!lua_isnil(L, -1)) /* non-nil return? */
488 lua_setfield(L, 2, name); /* _LOADED[name] = returned value */
489 lua_getfield(L, 2, name);
490 if (lua_touserdata(L, -1) == sentinel) { /* module did not set a value? */
491 lua_pushboolean(L, 1); /* use true as result */
492 lua_pushvalue(L, -1); /* extra copy to be returned */
493 lua_setfield(L, 2, name); /* _LOADED[name] = true */
495 return 1;
498 /* }====================================================== */
503 ** {======================================================
504 ** 'module' function
505 ** =======================================================
509 static void setfenv (lua_State *L) {
510 lua_Debug ar;
511 if (lua_getstack(L, 1, &ar) == 0 ||
512 lua_getinfo(L, "f", &ar) == 0 || /* get calling function */
513 lua_iscfunction(L, -1))
514 luaL_error(L, LUA_QL("module") " not called from a Lua function");
515 lua_pushvalue(L, -2);
516 lua_setfenv(L, -2);
517 lua_pop(L, 1);
521 static void dooptions (lua_State *L, int n) {
522 int i;
523 for (i = 2; i <= n; i++) {
524 lua_pushvalue(L, i); /* get option (a function) */
525 lua_pushvalue(L, -2); /* module */
526 lua_call(L, 1, 0);
531 static void modinit (lua_State *L, const char *modname) {
532 const char *dot;
533 lua_pushvalue(L, -1);
534 lua_setfield(L, -2, "_M"); /* module._M = module */
535 lua_pushstring(L, modname);
536 lua_setfield(L, -2, "_NAME");
537 dot = strrchr(modname, '.'); /* look for last dot in module name */
538 if (dot == NULL) dot = modname;
539 else dot++;
540 /* set _PACKAGE as package name (full module name minus last part) */
541 lua_pushlstring(L, modname, dot - modname);
542 lua_setfield(L, -2, "_PACKAGE");
546 static int ll_module (lua_State *L) {
547 const char *modname = luaL_checkstring(L, 1);
548 int loaded = lua_gettop(L) + 1; /* index of _LOADED table */
549 lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
550 lua_getfield(L, loaded, modname); /* get _LOADED[modname] */
551 if (!lua_istable(L, -1)) { /* not found? */
552 lua_pop(L, 1); /* remove previous result */
553 /* try global variable (and create one if it does not exist) */
554 if (luaL_findtable(L, LUA_GLOBALSINDEX, modname, 1) != NULL)
555 return luaL_error(L, "name conflict for module " LUA_QS, modname);
556 lua_pushvalue(L, -1);
557 lua_setfield(L, loaded, modname); /* _LOADED[modname] = new table */
559 /* check whether table already has a _NAME field */
560 lua_getfield(L, -1, "_NAME");
561 if (!lua_isnil(L, -1)) /* is table an initialized module? */
562 lua_pop(L, 1);
563 else { /* no; initialize it */
564 lua_pop(L, 1);
565 modinit(L, modname);
567 lua_pushvalue(L, -1);
568 setfenv(L);
569 dooptions(L, loaded - 1);
570 return 0;
574 static int ll_seeall (lua_State *L) {
575 luaL_checktype(L, 1, LUA_TTABLE);
576 if (!lua_getmetatable(L, 1)) {
577 lua_createtable(L, 0, 1); /* create new metatable */
578 lua_pushvalue(L, -1);
579 lua_setmetatable(L, 1);
581 lua_pushvalue(L, LUA_GLOBALSINDEX);
582 lua_setfield(L, -2, "__index"); /* mt.__index = _G */
583 return 0;
587 /* }====================================================== */
591 /* auxiliary mark (for internal use) */
592 #define AUXMARK "\1"
594 static void setpath (lua_State *L, const char *fieldname, const char *envname,
595 const char *def) {
596 const char *path = getenv(envname);
597 if (path == NULL) /* no environment variable? */
598 lua_pushstring(L, def); /* use default */
599 else {
600 /* replace ";;" by ";AUXMARK;" and then AUXMARK by default path */
601 path = luaL_gsub(L, path, LUA_PATHSEP LUA_PATHSEP,
602 LUA_PATHSEP AUXMARK LUA_PATHSEP);
603 luaL_gsub(L, path, AUXMARK, def);
604 lua_remove(L, -2);
606 setprogdir(L);
607 lua_setfield(L, -2, fieldname);
611 static const luaL_Reg pk_funcs[] = {
612 {"loadlib", ll_loadlib},
613 {"seeall", ll_seeall},
614 {NULL, NULL}
618 static const luaL_Reg ll_funcs[] = {
619 {"module", ll_module},
620 {"require", ll_require},
621 {NULL, NULL}
625 static const lua_CFunction loaders[] =
626 {loader_preload, loader_Lua, loader_C, loader_Croot, NULL};
629 LUALIB_API int luaopen_package (lua_State *L) {
630 int i;
631 /* create new type _LOADLIB */
632 luaL_newmetatable(L, "_LOADLIB");
633 lua_pushcfunction(L, gctm);
634 lua_setfield(L, -2, "__gc");
635 /* create `package' table */
636 luaL_register(L, LUA_LOADLIBNAME, pk_funcs);
637 #if defined(LUA_COMPAT_LOADLIB)
638 lua_getfield(L, -1, "loadlib");
639 lua_setfield(L, LUA_GLOBALSINDEX, "loadlib");
640 #endif
641 lua_pushvalue(L, -1);
642 lua_replace(L, LUA_ENVIRONINDEX);
643 /* create `loaders' table */
644 lua_createtable(L, sizeof(loaders)/sizeof(loaders[0]) - 1, 0);
645 /* fill it with pre-defined loaders */
646 for (i=0; loaders[i] != NULL; i++) {
647 lua_pushcfunction(L, loaders[i]);
648 lua_rawseti(L, -2, i+1);
650 lua_setfield(L, -2, "loaders"); /* put it in field `loaders' */
651 setpath(L, "path", LUA_PATH, LUA_PATH_DEFAULT); /* set field `path' */
652 setpath(L, "cpath", LUA_CPATH, LUA_CPATH_DEFAULT); /* set field `cpath' */
653 /* store config information */
654 lua_pushliteral(L, LUA_DIRSEP "\n" LUA_PATHSEP "\n" LUA_PATH_MARK "\n"
655 LUA_EXECDIR "\n" LUA_IGMARK);
656 lua_setfield(L, -2, "config");
657 /* set field `loaded' */
658 luaL_findtable(L, LUA_REGISTRYINDEX, "_LOADED", 2);
659 lua_setfield(L, -2, "loaded");
660 /* set field `preload' */
661 lua_newtable(L);
662 lua_setfield(L, -2, "preload");
663 lua_pushvalue(L, LUA_GLOBALSINDEX);
664 luaL_register(L, NULL, ll_funcs); /* open lib into global table */
665 lua_pop(L, 1);
666 return 1; /* return 'package' table */