2
** $Id: loadlib.c,v 1.52.1.3 2008/08/06 13:29:28 roberto Exp $
3
** Dynamic library loader for Lua
4
** See Copyright Notice in lua.h
6
** This module contains an implementation of loadlib for Unix systems
7
** that have dlfcn, an implementation for Darwin (Mac OS X), an
8
** implementation for Windows, and a stub for other systems.
25
/* prefix for open functions in C libraries */
26
#define LUA_POF "luaopen_"
28
/* separator for open functions in C libraries */
32
#define LIBPREFIX "LOADLIB: "
35
#define LIB_FAIL "open"
38
/* error codes for ll_loadfunc */
42
#define setprogdir(L) ((void)0)
45
static void ll_unloadlib (void *lib);
46
static void *ll_load (lua_State *L, const char *path);
47
static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym);
51
#if defined(LUA_DL_DLOPEN)
53
** {========================================================================
54
** This is an implementation of loadlib based on the dlfcn interface.
55
** The dlfcn interface is available in Linux, SunOS, Solaris, IRIX, FreeBSD,
56
** NetBSD, AIX 4.2, HPUX 11, and probably most other Unix flavors, at least
57
** as an emulation layer on top of native functions.
58
** =========================================================================
63
static void ll_unloadlib (void *lib) {
68
static void *ll_load (lua_State *L, const char *path) {
69
void *lib = dlopen(path, RTLD_NOW);
70
if (lib == NULL) lua_pushstring(L, dlerror());
75
static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
76
lua_CFunction f = (lua_CFunction)dlsym(lib, sym);
77
if (f == NULL) lua_pushstring(L, dlerror());
81
/* }====================================================== */
85
#elif defined(LUA_DL_DLL)
87
** {======================================================================
88
** This is an implementation of loadlib for Windows using native functions.
89
** =======================================================================
97
static void setprogdir (lua_State *L) {
98
char buff[MAX_PATH + 1];
100
DWORD nsize = sizeof(buff)/sizeof(char);
101
DWORD n = GetModuleFileNameA(NULL, buff, nsize);
102
if (n == 0 || n == nsize || (lb = strrchr(buff, '\\')) == NULL)
103
luaL_error(L, "unable to get ModuleFileName");
106
luaL_gsub(L, lua_tostring(L, -1), LUA_EXECDIR, buff);
107
lua_remove(L, -2); /* remove original string */
112
static void pusherror (lua_State *L) {
113
int error = GetLastError();
115
if (FormatMessageA(FORMAT_MESSAGE_IGNORE_INSERTS | FORMAT_MESSAGE_FROM_SYSTEM,
116
NULL, error, 0, buffer, sizeof(buffer), NULL))
117
lua_pushstring(L, buffer);
119
lua_pushfstring(L, "system error %d\n", error);
122
static void ll_unloadlib (void *lib) {
123
FreeLibrary((HINSTANCE)lib);
127
static void *ll_load (lua_State *L, const char *path) {
128
HINSTANCE lib = LoadLibraryA(path);
129
if (lib == NULL) pusherror(L);
134
static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
135
lua_CFunction f = (lua_CFunction)GetProcAddress((HINSTANCE)lib, sym);
136
if (f == NULL) pusherror(L);
140
/* }====================================================== */
144
#elif defined(LUA_DL_DYLD)
146
** {======================================================================
147
** Native Mac OS X / Darwin Implementation
148
** =======================================================================
151
#include <mach-o/dyld.h>
154
/* Mac appends a `_' before C function names */
156
#define POF "_" LUA_POF
159
static void pusherror (lua_State *L) {
161
const char *err_file;
162
NSLinkEditErrors err;
164
NSLinkEditError(&err, &err_num, &err_file, &err_str);
165
lua_pushstring(L, err_str);
169
static const char *errorfromcode (NSObjectFileImageReturnCode ret) {
171
case NSObjectFileImageInappropriateFile:
172
return "file is not a bundle";
173
case NSObjectFileImageArch:
174
return "library is for wrong CPU type";
175
case NSObjectFileImageFormat:
177
case NSObjectFileImageAccess:
178
return "cannot access file";
179
case NSObjectFileImageFailure:
181
return "unable to load library";
186
static void ll_unloadlib (void *lib) {
187
NSUnLinkModule((NSModule)lib, NSUNLINKMODULE_OPTION_RESET_LAZY_REFERENCES);
191
static void *ll_load (lua_State *L, const char *path) {
192
NSObjectFileImage img;
193
NSObjectFileImageReturnCode ret;
194
/* this would be a rare case, but prevents crashing if it happens */
195
if(!_dyld_present()) {
196
lua_pushliteral(L, "dyld not present");
199
ret = NSCreateObjectFileImageFromFile(path, &img);
200
if (ret == NSObjectFileImageSuccess) {
201
NSModule mod = NSLinkModule(img, path, NSLINKMODULE_OPTION_PRIVATE |
202
NSLINKMODULE_OPTION_RETURN_ON_ERROR);
203
NSDestroyObjectFileImage(img);
204
if (mod == NULL) pusherror(L);
207
lua_pushstring(L, errorfromcode(ret));
212
static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
213
NSSymbol nss = NSLookupSymbolInModule((NSModule)lib, sym);
215
lua_pushfstring(L, "symbol " LUA_QS " not found", sym);
218
return (lua_CFunction)NSAddressOfSymbol(nss);
221
/* }====================================================== */
227
** {======================================================
228
** Fallback for other systems
229
** =======================================================
233
#define LIB_FAIL "absent"
236
#define DLMSG "dynamic libraries not enabled; check your Lua installation"
239
static void ll_unloadlib (void *lib) {
240
(void)lib; /* to avoid warnings */
244
static void *ll_load (lua_State *L, const char *path) {
245
(void)path; /* to avoid warnings */
246
lua_pushliteral(L, DLMSG);
251
static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
252
(void)lib; (void)sym; /* to avoid warnings */
253
lua_pushliteral(L, DLMSG);
257
/* }====================================================== */
262
static void **ll_register (lua_State *L, const char *path) {
264
lua_pushfstring(L, "%s%s", LIBPREFIX, path);
265
lua_gettable(L, LUA_REGISTRYINDEX); /* check library in registry? */
266
if (!lua_isnil(L, -1)) /* is there an entry? */
267
plib = (void **)lua_touserdata(L, -1);
268
else { /* no entry yet; create one */
270
plib = (void **)lua_newuserdata(L, sizeof(const void *));
272
luaL_getmetatable(L, "_LOADLIB");
273
lua_setmetatable(L, -2);
274
lua_pushfstring(L, "%s%s", LIBPREFIX, path);
275
lua_pushvalue(L, -2);
276
lua_settable(L, LUA_REGISTRYINDEX);
283
** __gc tag method: calls library's `ll_unloadlib' function with the lib
286
static int gctm (lua_State *L) {
287
void **lib = (void **)luaL_checkudata(L, 1, "_LOADLIB");
288
if (*lib) ll_unloadlib(*lib);
289
*lib = NULL; /* mark library as closed */
294
static int ll_loadfunc (lua_State *L, const char *path, const char *sym) {
295
void **reg = ll_register(L, path);
296
if (*reg == NULL) *reg = ll_load(L, path);
298
return ERRLIB; /* unable to load library */
300
lua_CFunction f = ll_sym(L, *reg, sym);
302
return ERRFUNC; /* unable to find function */
303
lua_pushcfunction(L, f);
304
return 0; /* return function */
309
static int ll_loadlib (lua_State *L) {
310
const char *path = luaL_checkstring(L, 1);
311
const char *init = luaL_checkstring(L, 2);
312
int stat = ll_loadfunc(L, path, init);
313
if (stat == 0) /* no errors? */
314
return 1; /* return the loaded function */
315
else { /* error; error message is on stack top */
318
lua_pushstring(L, (stat == ERRLIB) ? LIB_FAIL : "init");
319
return 3; /* return nil, error message, and where */
326
** {======================================================
327
** 'require' function
328
** =======================================================
332
static int readable (const char *filename) {
333
FILE *f = fopen(filename, "r"); /* try to open file */
334
if (f == NULL) return 0; /* open failed */
340
static const char *pushnexttemplate (lua_State *L, const char *path) {
342
while (*path == *LUA_PATHSEP) path++; /* skip separators */
343
if (*path == '\0') return NULL; /* no more templates */
344
l = strchr(path, *LUA_PATHSEP); /* find next separator */
345
if (l == NULL) l = path + strlen(path);
346
lua_pushlstring(L, path, l - path); /* template */
351
static const char *findfile (lua_State *L, const char *name,
354
name = luaL_gsub(L, name, ".", LUA_DIRSEP);
355
lua_getfield(L, LUA_ENVIRONINDEX, pname);
356
path = lua_tostring(L, -1);
358
luaL_error(L, LUA_QL("package.%s") " must be a string", pname);
359
lua_pushliteral(L, ""); /* error accumulator */
360
while ((path = pushnexttemplate(L, path)) != NULL) {
361
const char *filename;
362
filename = luaL_gsub(L, lua_tostring(L, -1), LUA_PATH_MARK, name);
363
lua_remove(L, -2); /* remove path template */
364
if (readable(filename)) /* does file exist and is readable? */
365
return filename; /* return that file name */
366
lua_pushfstring(L, "\n\tno file " LUA_QS, filename);
367
lua_remove(L, -2); /* remove file name */
368
lua_concat(L, 2); /* add entry to possible error message */
370
return NULL; /* not found */
374
static void loaderror (lua_State *L, const char *filename) {
375
luaL_error(L, "error loading module " LUA_QS " from file " LUA_QS ":\n\t%s",
376
lua_tostring(L, 1), filename, lua_tostring(L, -1));
380
static int loader_Lua (lua_State *L) {
381
const char *filename;
382
const char *name = luaL_checkstring(L, 1);
383
filename = findfile(L, name, "path");
384
if (filename == NULL) return 1; /* library not found in this path */
385
if (luaL_loadfile(L, filename) != 0)
386
loaderror(L, filename);
387
return 1; /* library loaded successfully */
391
static const char *mkfuncname (lua_State *L, const char *modname) {
392
const char *funcname;
393
const char *mark = strchr(modname, *LUA_IGMARK);
394
if (mark) modname = mark + 1;
395
funcname = luaL_gsub(L, modname, ".", LUA_OFSEP);
396
funcname = lua_pushfstring(L, POF"%s", funcname);
397
lua_remove(L, -2); /* remove 'gsub' result */
402
static int loader_C (lua_State *L) {
403
const char *funcname;
404
const char *name = luaL_checkstring(L, 1);
405
const char *filename = findfile(L, name, "cpath");
406
if (filename == NULL) return 1; /* library not found in this path */
407
funcname = mkfuncname(L, name);
408
if (ll_loadfunc(L, filename, funcname) != 0)
409
loaderror(L, filename);
410
return 1; /* library loaded successfully */
414
static int loader_Croot (lua_State *L) {
415
const char *funcname;
416
const char *filename;
417
const char *name = luaL_checkstring(L, 1);
418
const char *p = strchr(name, '.');
420
if (p == NULL) return 0; /* is root */
421
lua_pushlstring(L, name, p - name);
422
filename = findfile(L, lua_tostring(L, -1), "cpath");
423
if (filename == NULL) return 1; /* root not found */
424
funcname = mkfuncname(L, name);
425
if ((stat = ll_loadfunc(L, filename, funcname)) != 0) {
426
if (stat != ERRFUNC) loaderror(L, filename); /* real error */
427
lua_pushfstring(L, "\n\tno module " LUA_QS " in file " LUA_QS,
429
return 1; /* function not found */
435
static int loader_preload (lua_State *L) {
436
const char *name = luaL_checkstring(L, 1);
437
lua_getfield(L, LUA_ENVIRONINDEX, "preload");
438
if (!lua_istable(L, -1))
439
luaL_error(L, LUA_QL("package.preload") " must be a table");
440
lua_getfield(L, -1, name);
441
if (lua_isnil(L, -1)) /* not found? */
442
lua_pushfstring(L, "\n\tno field package.preload['%s']", name);
447
static const int sentinel_ = 0;
448
#define sentinel ((void *)&sentinel_)
451
static int ll_require (lua_State *L) {
452
const char *name = luaL_checkstring(L, 1);
454
lua_settop(L, 1); /* _LOADED table will be at index 2 */
455
lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
456
lua_getfield(L, 2, name);
457
if (lua_toboolean(L, -1)) { /* is it there? */
458
if (lua_touserdata(L, -1) == sentinel) /* check loops */
459
luaL_error(L, "loop or previous error loading module " LUA_QS, name);
460
return 1; /* package is already loaded */
462
/* else must load it; iterate over available loaders */
463
lua_getfield(L, LUA_ENVIRONINDEX, "loaders");
464
if (!lua_istable(L, -1))
465
luaL_error(L, LUA_QL("package.loaders") " must be a table");
466
lua_pushliteral(L, ""); /* error message accumulator */
468
lua_rawgeti(L, -2, i); /* get a loader */
469
if (lua_isnil(L, -1))
470
luaL_error(L, "module " LUA_QS " not found:%s",
471
name, lua_tostring(L, -2));
472
lua_pushstring(L, name);
473
lua_call(L, 1, 1); /* call it */
474
if (lua_isfunction(L, -1)) /* did it find module? */
475
break; /* module loaded successfully */
476
else if (lua_isstring(L, -1)) /* loader returned error message? */
477
lua_concat(L, 2); /* accumulate it */
481
lua_pushlightuserdata(L, sentinel);
482
lua_setfield(L, 2, name); /* _LOADED[name] = sentinel */
483
lua_pushstring(L, name); /* pass name as argument to module */
484
lua_call(L, 1, 1); /* run loaded module */
485
if (!lua_isnil(L, -1)) /* non-nil return? */
486
lua_setfield(L, 2, name); /* _LOADED[name] = returned value */
487
lua_getfield(L, 2, name);
488
if (lua_touserdata(L, -1) == sentinel) { /* module did not set a value? */
489
lua_pushboolean(L, 1); /* use true as result */
490
lua_pushvalue(L, -1); /* extra copy to be returned */
491
lua_setfield(L, 2, name); /* _LOADED[name] = true */
496
/* }====================================================== */
501
** {======================================================
503
** =======================================================
507
static void setfenv (lua_State *L) {
509
if (lua_getstack(L, 1, &ar) == 0 ||
510
lua_getinfo(L, "f", &ar) == 0 || /* get calling function */
511
lua_iscfunction(L, -1))
512
luaL_error(L, LUA_QL("module") " not called from a Lua function");
513
lua_pushvalue(L, -2);
519
static void dooptions (lua_State *L, int n) {
521
for (i = 2; i <= n; i++) {
522
lua_pushvalue(L, i); /* get option (a function) */
523
lua_pushvalue(L, -2); /* module */
529
static void modinit (lua_State *L, const char *modname) {
531
lua_pushvalue(L, -1);
532
lua_setfield(L, -2, "_M"); /* module._M = module */
533
lua_pushstring(L, modname);
534
lua_setfield(L, -2, "_NAME");
535
dot = strrchr(modname, '.'); /* look for last dot in module name */
536
if (dot == NULL) dot = modname;
538
/* set _PACKAGE as package name (full module name minus last part) */
539
lua_pushlstring(L, modname, dot - modname);
540
lua_setfield(L, -2, "_PACKAGE");
544
static int ll_module (lua_State *L) {
545
const char *modname = luaL_checkstring(L, 1);
546
int loaded = lua_gettop(L) + 1; /* index of _LOADED table */
547
lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
548
lua_getfield(L, loaded, modname); /* get _LOADED[modname] */
549
if (!lua_istable(L, -1)) { /* not found? */
550
lua_pop(L, 1); /* remove previous result */
551
/* try global variable (and create one if it does not exist) */
552
if (luaL_findtable(L, LUA_GLOBALSINDEX, modname, 1) != NULL)
553
return luaL_error(L, "name conflict for module " LUA_QS, modname);
554
lua_pushvalue(L, -1);
555
lua_setfield(L, loaded, modname); /* _LOADED[modname] = new table */
557
/* check whether table already has a _NAME field */
558
lua_getfield(L, -1, "_NAME");
559
if (!lua_isnil(L, -1)) /* is table an initialized module? */
561
else { /* no; initialize it */
565
lua_pushvalue(L, -1);
567
dooptions(L, loaded - 1);
572
static int ll_seeall (lua_State *L) {
573
luaL_checktype(L, 1, LUA_TTABLE);
574
if (!lua_getmetatable(L, 1)) {
575
lua_createtable(L, 0, 1); /* create new metatable */
576
lua_pushvalue(L, -1);
577
lua_setmetatable(L, 1);
579
lua_pushvalue(L, LUA_GLOBALSINDEX);
580
lua_setfield(L, -2, "__index"); /* mt.__index = _G */
585
/* }====================================================== */
589
/* auxiliary mark (for internal use) */
592
static void setpath (lua_State *L, const char *fieldname, const char *envname,
594
const char *path = getenv(envname);
595
if (path == NULL) /* no environment variable? */
596
lua_pushstring(L, def); /* use default */
598
/* replace ";;" by ";AUXMARK;" and then AUXMARK by default path */
599
path = luaL_gsub(L, path, LUA_PATHSEP LUA_PATHSEP,
600
LUA_PATHSEP AUXMARK LUA_PATHSEP);
601
luaL_gsub(L, path, AUXMARK, def);
605
lua_setfield(L, -2, fieldname);
609
static const luaL_Reg pk_funcs[] = {
610
{"loadlib", ll_loadlib},
611
{"seeall", ll_seeall},
616
static const luaL_Reg ll_funcs[] = {
617
{"module", ll_module},
618
{"require", ll_require},
623
static const lua_CFunction loaders[] =
624
{loader_preload, loader_Lua, loader_C, loader_Croot, NULL};
627
LUALIB_API int luaopen_package (lua_State *L) {
629
/* create new type _LOADLIB */
630
luaL_newmetatable(L, "_LOADLIB");
631
lua_pushcfunction(L, gctm);
632
lua_setfield(L, -2, "__gc");
633
/* create `package' table */
634
luaL_register(L, LUA_LOADLIBNAME, pk_funcs);
635
#if defined(LUA_COMPAT_LOADLIB)
636
lua_getfield(L, -1, "loadlib");
637
lua_setfield(L, LUA_GLOBALSINDEX, "loadlib");
639
lua_pushvalue(L, -1);
640
lua_replace(L, LUA_ENVIRONINDEX);
641
/* create `loaders' table */
642
lua_createtable(L, 0, sizeof(loaders)/sizeof(loaders[0]) - 1);
643
/* fill it with pre-defined loaders */
644
for (i=0; loaders[i] != NULL; i++) {
645
lua_pushcfunction(L, loaders[i]);
646
lua_rawseti(L, -2, i+1);
648
lua_setfield(L, -2, "loaders"); /* put it in field `loaders' */
649
setpath(L, "path", LUA_PATH, LUA_PATH_DEFAULT); /* set field `path' */
650
setpath(L, "cpath", LUA_CPATH, LUA_CPATH_DEFAULT); /* set field `cpath' */
651
/* store config information */
652
lua_pushliteral(L, LUA_DIRSEP "\n" LUA_PATHSEP "\n" LUA_PATH_MARK "\n"
653
LUA_EXECDIR "\n" LUA_IGMARK);
654
lua_setfield(L, -2, "config");
655
/* set field `loaded' */
656
luaL_findtable(L, LUA_REGISTRYINDEX, "_LOADED", 2);
657
lua_setfield(L, -2, "loaded");
658
/* set field `preload' */
660
lua_setfield(L, -2, "preload");
661
lua_pushvalue(L, LUA_GLOBALSINDEX);
662
luaL_register(L, NULL, ll_funcs); /* open lib into global table */
664
return 1; /* return 'package' table */
added
removed
script/lua/loadlib.c
