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Diffstat (limited to 'lua/src/loadlib.c')
| -rw-r--r-- | lua/src/loadlib.c | 725 |
1 files changed, 725 insertions, 0 deletions
diff --git a/lua/src/loadlib.c b/lua/src/loadlib.c new file mode 100644 index 0000000..bedbea3 --- /dev/null +++ b/lua/src/loadlib.c @@ -0,0 +1,725 @@ +/* +** $Id: loadlib.c,v 1.111.1.1 2013/04/12 18:48:47 roberto Exp $ +** Dynamic library loader for Lua +** See Copyright Notice in lua.h +** +** This module contains an implementation of loadlib for Unix systems +** that have dlfcn, an implementation for Windows, and a stub for other +** systems. +*/ + + +/* +** if needed, includes windows header before everything else +*/ +#if defined(_WIN32) +#include <windows.h> +#endif + + +#include <stdlib.h> +#include <string.h> + + +#define loadlib_c +#define LUA_LIB + +#include "lua.h" + +#include "lauxlib.h" +#include "lualib.h" + + +/* +** LUA_PATH and LUA_CPATH are the names of the environment +** variables that Lua check to set its paths. +*/ +#if !defined(LUA_PATH) +#define LUA_PATH "LUA_PATH" +#endif + +#if !defined(LUA_CPATH) +#define LUA_CPATH "LUA_CPATH" +#endif + +#define LUA_PATHSUFFIX "_" LUA_VERSION_MAJOR "_" LUA_VERSION_MINOR + +#define LUA_PATHVERSION LUA_PATH LUA_PATHSUFFIX +#define LUA_CPATHVERSION LUA_CPATH LUA_PATHSUFFIX + +/* +** LUA_PATH_SEP is the character that separates templates in a path. +** LUA_PATH_MARK is the string that marks the substitution points in a +** template. +** LUA_EXEC_DIR in a Windows path is replaced by the executable's +** directory. +** LUA_IGMARK is a mark to ignore all before it when building the +** luaopen_ function name. +*/ +#if !defined (LUA_PATH_SEP) +#define LUA_PATH_SEP ";" +#endif +#if !defined (LUA_PATH_MARK) +#define LUA_PATH_MARK "?" +#endif +#if !defined (LUA_EXEC_DIR) +#define LUA_EXEC_DIR "!" +#endif +#if !defined (LUA_IGMARK) +#define LUA_IGMARK "-" +#endif + + +/* +** LUA_CSUBSEP is the character that replaces dots in submodule names +** when searching for a C loader. +** LUA_LSUBSEP is the character that replaces dots in submodule names +** when searching for a Lua loader. +*/ +#if !defined(LUA_CSUBSEP) +#define LUA_CSUBSEP LUA_DIRSEP +#endif + +#if !defined(LUA_LSUBSEP) +#define LUA_LSUBSEP LUA_DIRSEP +#endif + + +/* prefix for open functions in C libraries */ +#define LUA_POF "luaopen_" + +/* separator for open functions in C libraries */ +#define LUA_OFSEP "_" + + +/* table (in the registry) that keeps handles for all loaded C libraries */ +#define CLIBS "_CLIBS" + +#define LIB_FAIL "open" + + +/* error codes for ll_loadfunc */ +#define ERRLIB 1 +#define ERRFUNC 2 + +#define setprogdir(L) ((void)0) + + +/* +** system-dependent functions +*/ +static void ll_unloadlib (void *lib); +static void *ll_load (lua_State *L, const char *path, int seeglb); +static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym); + + + +#if defined(LUA_USE_DLOPEN) +/* +** {======================================================================== +** This is an implementation of loadlib based on the dlfcn interface. +** The dlfcn interface is available in Linux, SunOS, Solaris, IRIX, FreeBSD, +** NetBSD, AIX 4.2, HPUX 11, and probably most other Unix flavors, at least +** as an emulation layer on top of native functions. +** ========================================================================= +*/ + +#include <dlfcn.h> + +static void ll_unloadlib (void *lib) { + dlclose(lib); +} + + +static void *ll_load (lua_State *L, const char *path, int seeglb) { + void *lib = dlopen(path, RTLD_NOW | (seeglb ? RTLD_GLOBAL : RTLD_LOCAL)); + if (lib == NULL) lua_pushstring(L, dlerror()); + return lib; +} + + +static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) { + lua_CFunction f = (lua_CFunction)dlsym(lib, sym); + if (f == NULL) lua_pushstring(L, dlerror()); + return f; +} + +/* }====================================================== */ + + + +#elif defined(LUA_DL_DLL) +/* +** {====================================================================== +** This is an implementation of loadlib for Windows using native functions. +** ======================================================================= +*/ + +#undef setprogdir + +/* +** optional flags for LoadLibraryEx +*/ +#if !defined(LUA_LLE_FLAGS) +#define LUA_LLE_FLAGS 0 +#endif + + +static void setprogdir (lua_State *L) { + char buff[MAX_PATH + 1]; + char *lb; + DWORD nsize = sizeof(buff)/sizeof(char); + DWORD n = GetModuleFileNameA(NULL, buff, nsize); + if (n == 0 || n == nsize || (lb = strrchr(buff, '\\')) == NULL) + luaL_error(L, "unable to get ModuleFileName"); + else { + *lb = '\0'; + luaL_gsub(L, lua_tostring(L, -1), LUA_EXEC_DIR, buff); + lua_remove(L, -2); /* remove original string */ + } +} + + +static void pusherror (lua_State *L) { + int error = GetLastError(); + char buffer[128]; + if (FormatMessageA(FORMAT_MESSAGE_IGNORE_INSERTS | FORMAT_MESSAGE_FROM_SYSTEM, + NULL, error, 0, buffer, sizeof(buffer)/sizeof(char), NULL)) + lua_pushstring(L, buffer); + else + lua_pushfstring(L, "system error %d\n", error); +} + +static void ll_unloadlib (void *lib) { + FreeLibrary((HMODULE)lib); +} + + +static void *ll_load (lua_State *L, const char *path, int seeglb) { + HMODULE lib = LoadLibraryExA(path, NULL, LUA_LLE_FLAGS); + (void)(seeglb); /* not used: symbols are 'global' by default */ + if (lib == NULL) pusherror(L); + return lib; +} + + +static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) { + lua_CFunction f = (lua_CFunction)GetProcAddress((HMODULE)lib, sym); + if (f == NULL) pusherror(L); + return f; +} + +/* }====================================================== */ + + +#else +/* +** {====================================================== +** Fallback for other systems +** ======================================================= +*/ + +#undef LIB_FAIL +#define LIB_FAIL "absent" + + +#define DLMSG "dynamic libraries not enabled; check your Lua installation" + + +static void ll_unloadlib (void *lib) { + (void)(lib); /* not used */ +} + + +static void *ll_load (lua_State *L, const char *path, int seeglb) { + (void)(path); (void)(seeglb); /* not used */ + lua_pushliteral(L, DLMSG); + return NULL; +} + + +static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) { + (void)(lib); (void)(sym); /* not used */ + lua_pushliteral(L, DLMSG); + return NULL; +} + +/* }====================================================== */ +#endif + + +static void *ll_checkclib (lua_State *L, const char *path) { + void *plib; + lua_getfield(L, LUA_REGISTRYINDEX, CLIBS); + lua_getfield(L, -1, path); + plib = lua_touserdata(L, -1); /* plib = CLIBS[path] */ + lua_pop(L, 2); /* pop CLIBS table and 'plib' */ + return plib; +} + + +static void ll_addtoclib (lua_State *L, const char *path, void *plib) { + lua_getfield(L, LUA_REGISTRYINDEX, CLIBS); + lua_pushlightuserdata(L, plib); + lua_pushvalue(L, -1); + lua_setfield(L, -3, path); /* CLIBS[path] = plib */ + lua_rawseti(L, -2, luaL_len(L, -2) + 1); /* CLIBS[#CLIBS + 1] = plib */ + lua_pop(L, 1); /* pop CLIBS table */ +} + + +/* +** __gc tag method for CLIBS table: calls 'll_unloadlib' for all lib +** handles in list CLIBS +*/ +static int gctm (lua_State *L) { + int n = luaL_len(L, 1); + for (; n >= 1; n--) { /* for each handle, in reverse order */ + lua_rawgeti(L, 1, n); /* get handle CLIBS[n] */ + ll_unloadlib(lua_touserdata(L, -1)); + lua_pop(L, 1); /* pop handle */ + } + return 0; +} + + +static int ll_loadfunc (lua_State *L, const char *path, const char *sym) { + void *reg = ll_checkclib(L, path); /* check loaded C libraries */ + if (reg == NULL) { /* must load library? */ + reg = ll_load(L, path, *sym == '*'); + if (reg == NULL) return ERRLIB; /* unable to load library */ + ll_addtoclib(L, path, reg); + } + if (*sym == '*') { /* loading only library (no function)? */ + lua_pushboolean(L, 1); /* return 'true' */ + return 0; /* no errors */ + } + else { + lua_CFunction f = ll_sym(L, reg, sym); + if (f == NULL) + return ERRFUNC; /* unable to find function */ + lua_pushcfunction(L, f); /* else create new function */ + return 0; /* no errors */ + } +} + + +static int ll_loadlib (lua_State *L) { + const char *path = luaL_checkstring(L, 1); + const char *init = luaL_checkstring(L, 2); + int stat = ll_loadfunc(L, path, init); + if (stat == 0) /* no errors? */ + return 1; /* return the loaded function */ + else { /* error; error message is on stack top */ + lua_pushnil(L); + lua_insert(L, -2); + lua_pushstring(L, (stat == ERRLIB) ? LIB_FAIL : "init"); + return 3; /* return nil, error message, and where */ + } +} + + + +/* +** {====================================================== +** 'require' function +** ======================================================= +*/ + + +static int readable (const char *filename) { + FILE *f = fopen(filename, "r"); /* try to open file */ + if (f == NULL) return 0; /* open failed */ + fclose(f); + return 1; +} + + +static const char *pushnexttemplate (lua_State *L, const char *path) { + const char *l; + while (*path == *LUA_PATH_SEP) path++; /* skip separators */ + if (*path == '\0') return NULL; /* no more templates */ + l = strchr(path, *LUA_PATH_SEP); /* find next separator */ + if (l == NULL) l = path + strlen(path); + lua_pushlstring(L, path, l - path); /* template */ + return l; +} + + +static const char *searchpath (lua_State *L, const char *name, + const char *path, + const char *sep, + const char *dirsep) { + luaL_Buffer msg; /* to build error message */ + luaL_buffinit(L, &msg); + if (*sep != '\0') /* non-empty separator? */ + name = luaL_gsub(L, name, sep, dirsep); /* replace it by 'dirsep' */ + while ((path = pushnexttemplate(L, path)) != NULL) { + const char *filename = luaL_gsub(L, lua_tostring(L, -1), + LUA_PATH_MARK, name); + lua_remove(L, -2); /* remove path template */ + if (readable(filename)) /* does file exist and is readable? */ + return filename; /* return that file name */ + lua_pushfstring(L, "\n\tno file " LUA_QS, filename); + lua_remove(L, -2); /* remove file name */ + luaL_addvalue(&msg); /* concatenate error msg. entry */ + } + luaL_pushresult(&msg); /* create error message */ + return NULL; /* not found */ +} + + +static int ll_searchpath (lua_State *L) { + const char *f = searchpath(L, luaL_checkstring(L, 1), + luaL_checkstring(L, 2), + luaL_optstring(L, 3, "."), + luaL_optstring(L, 4, LUA_DIRSEP)); + if (f != NULL) return 1; + else { /* error message is on top of the stack */ + lua_pushnil(L); + lua_insert(L, -2); + return 2; /* return nil + error message */ + } +} + + +static const char *findfile (lua_State *L, const char *name, + const char *pname, + const char *dirsep) { + const char *path; + lua_getfield(L, lua_upvalueindex(1), pname); + path = lua_tostring(L, -1); + if (path == NULL) + luaL_error(L, LUA_QL("package.%s") " must be a string", pname); + return searchpath(L, name, path, ".", dirsep); +} + + +static int checkload (lua_State *L, int stat, const char *filename) { + if (stat) { /* module loaded successfully? */ + lua_pushstring(L, filename); /* will be 2nd argument to module */ + return 2; /* return open function and file name */ + } + else + return luaL_error(L, "error loading module " LUA_QS + " from file " LUA_QS ":\n\t%s", + lua_tostring(L, 1), filename, lua_tostring(L, -1)); +} + + +static int searcher_Lua (lua_State *L) { + const char *filename; + const char *name = luaL_checkstring(L, 1); + filename = findfile(L, name, "path", LUA_LSUBSEP); + if (filename == NULL) return 1; /* module not found in this path */ + return checkload(L, (luaL_loadfile(L, filename) == LUA_OK), filename); +} + + +static int loadfunc (lua_State *L, const char *filename, const char *modname) { + const char *funcname; + const char *mark; + modname = luaL_gsub(L, modname, ".", LUA_OFSEP); + mark = strchr(modname, *LUA_IGMARK); + if (mark) { + int stat; + funcname = lua_pushlstring(L, modname, mark - modname); + funcname = lua_pushfstring(L, LUA_POF"%s", funcname); + stat = ll_loadfunc(L, filename, funcname); + if (stat != ERRFUNC) return stat; + modname = mark + 1; /* else go ahead and try old-style name */ + } + funcname = lua_pushfstring(L, LUA_POF"%s", modname); + return ll_loadfunc(L, filename, funcname); +} + + +static int searcher_C (lua_State *L) { + const char *name = luaL_checkstring(L, 1); + const char *filename = findfile(L, name, "cpath", LUA_CSUBSEP); + if (filename == NULL) return 1; /* module not found in this path */ + return checkload(L, (loadfunc(L, filename, name) == 0), filename); +} + + +static int searcher_Croot (lua_State *L) { + const char *filename; + const char *name = luaL_checkstring(L, 1); + const char *p = strchr(name, '.'); + int stat; + if (p == NULL) return 0; /* is root */ + lua_pushlstring(L, name, p - name); + filename = findfile(L, lua_tostring(L, -1), "cpath", LUA_CSUBSEP); + if (filename == NULL) return 1; /* root not found */ + if ((stat = loadfunc(L, filename, name)) != 0) { + if (stat != ERRFUNC) + return checkload(L, 0, filename); /* real error */ + else { /* open function not found */ + lua_pushfstring(L, "\n\tno module " LUA_QS " in file " LUA_QS, + name, filename); + return 1; + } + } + lua_pushstring(L, filename); /* will be 2nd argument to module */ + return 2; +} + + +static int searcher_preload (lua_State *L) { + const char *name = luaL_checkstring(L, 1); + lua_getfield(L, LUA_REGISTRYINDEX, "_PRELOAD"); + lua_getfield(L, -1, name); + if (lua_isnil(L, -1)) /* not found? */ + lua_pushfstring(L, "\n\tno field package.preload['%s']", name); + return 1; +} + + +static void findloader (lua_State *L, const char *name) { + int i; + luaL_Buffer msg; /* to build error message */ + luaL_buffinit(L, &msg); + lua_getfield(L, lua_upvalueindex(1), "searchers"); /* will be at index 3 */ + if (!lua_istable(L, 3)) + luaL_error(L, LUA_QL("package.searchers") " must be a table"); + /* iterate over available searchers to find a loader */ + for (i = 1; ; i++) { + lua_rawgeti(L, 3, i); /* get a searcher */ + if (lua_isnil(L, -1)) { /* no more searchers? */ + lua_pop(L, 1); /* remove nil */ + luaL_pushresult(&msg); /* create error message */ + luaL_error(L, "module " LUA_QS " not found:%s", + name, lua_tostring(L, -1)); + } + lua_pushstring(L, name); + lua_call(L, 1, 2); /* call it */ + if (lua_isfunction(L, -2)) /* did it find a loader? */ + return; /* module loader found */ + else if (lua_isstring(L, -2)) { /* searcher returned error message? */ + lua_pop(L, 1); /* remove extra return */ + luaL_addvalue(&msg); /* concatenate error message */ + } + else + lua_pop(L, 2); /* remove both returns */ + } +} + + +static int ll_require (lua_State *L) { + const char *name = luaL_checkstring(L, 1); + lua_settop(L, 1); /* _LOADED table will be at index 2 */ + lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED"); + lua_getfield(L, 2, name); /* _LOADED[name] */ + if (lua_toboolean(L, -1)) /* is it there? */ + return 1; /* package is already loaded */ + /* else must load package */ + lua_pop(L, 1); /* remove 'getfield' result */ + findloader(L, name); + lua_pushstring(L, name); /* pass name as argument to module loader */ + lua_insert(L, -2); /* name is 1st argument (before search data) */ + lua_call(L, 2, 1); /* run loader to load module */ + if (!lua_isnil(L, -1)) /* non-nil return? */ + lua_setfield(L, 2, name); /* _LOADED[name] = returned value */ + lua_getfield(L, 2, name); + if (lua_isnil(L, -1)) { /* module did not set a value? */ + lua_pushboolean(L, 1); /* use true as result */ + lua_pushvalue(L, -1); /* extra copy to be returned */ + lua_setfield(L, 2, name); /* _LOADED[name] = true */ + } + return 1; +} + +/* }====================================================== */ + + + +/* +** {====================================================== +** 'module' function +** ======================================================= +*/ +#if defined(LUA_COMPAT_MODULE) + +/* +** changes the environment variable of calling function +*/ +static void set_env (lua_State *L) { + lua_Debug ar; + if (lua_getstack(L, 1, &ar) == 0 || + lua_getinfo(L, "f", &ar) == 0 || /* get calling function */ + lua_iscfunction(L, -1)) + luaL_error(L, LUA_QL("module") " not called from a Lua function"); + lua_pushvalue(L, -2); /* copy new environment table to top */ + lua_setupvalue(L, -2, 1); + lua_pop(L, 1); /* remove function */ +} + + +static void dooptions (lua_State *L, int n) { + int i; + for (i = 2; i <= n; i++) { + if (lua_isfunction(L, i)) { /* avoid 'calling' extra info. */ + lua_pushvalue(L, i); /* get option (a function) */ + lua_pushvalue(L, -2); /* module */ + lua_call(L, 1, 0); + } + } +} + + +static void modinit (lua_State *L, const char *modname) { + const char *dot; + lua_pushvalue(L, -1); + lua_setfield(L, -2, "_M"); /* module._M = module */ + lua_pushstring(L, modname); + lua_setfield(L, -2, "_NAME"); + dot = strrchr(modname, '.'); /* look for last dot in module name */ + if (dot == NULL) dot = modname; + else dot++; + /* set _PACKAGE as package name (full module name minus last part) */ + lua_pushlstring(L, modname, dot - modname); + lua_setfield(L, -2, "_PACKAGE"); +} + + +static int ll_module (lua_State *L) { + const char *modname = luaL_checkstring(L, 1); + int lastarg = lua_gettop(L); /* last parameter */ + luaL_pushmodule(L, modname, 1); /* get/create module table */ + /* check whether table already has a _NAME field */ + lua_getfield(L, -1, "_NAME"); + if (!lua_isnil(L, -1)) /* is table an initialized module? */ + lua_pop(L, 1); + else { /* no; initialize it */ + lua_pop(L, 1); + modinit(L, modname); + } + lua_pushvalue(L, -1); + set_env(L); + dooptions(L, lastarg); + return 1; +} + + +static int ll_seeall (lua_State *L) { + luaL_checktype(L, 1, LUA_TTABLE); + if (!lua_getmetatable(L, 1)) { + lua_createtable(L, 0, 1); /* create new metatable */ + lua_pushvalue(L, -1); + lua_setmetatable(L, 1); + } + lua_pushglobaltable(L); + lua_setfield(L, -2, "__index"); /* mt.__index = _G */ + return 0; +} + +#endif +/* }====================================================== */ + + + +/* auxiliary mark (for internal use) */ +#define AUXMARK "\1" + + +/* +** return registry.LUA_NOENV as a boolean +*/ +static int noenv (lua_State *L) { + int b; + lua_getfield(L, LUA_REGISTRYINDEX, "LUA_NOENV"); + b = lua_toboolean(L, -1); + lua_pop(L, 1); /* remove value */ + return b; +} + + +static void setpath (lua_State *L, const char *fieldname, const char *envname1, + const char *envname2, const char *def) { + const char *path = getenv(envname1); + if (path == NULL) /* no environment variable? */ + path = getenv(envname2); /* try alternative name */ + if (path == NULL || noenv(L)) /* no environment variable? */ + lua_pushstring(L, def); /* use default */ + else { + /* replace ";;" by ";AUXMARK;" and then AUXMARK by default path */ + path = luaL_gsub(L, path, LUA_PATH_SEP LUA_PATH_SEP, + LUA_PATH_SEP AUXMARK LUA_PATH_SEP); + luaL_gsub(L, path, AUXMARK, def); + lua_remove(L, -2); + } + setprogdir(L); + lua_setfield(L, -2, fieldname); +} + + +static const luaL_Reg pk_funcs[] = { + {"loadlib", ll_loadlib}, + {"searchpath", ll_searchpath}, +#if defined(LUA_COMPAT_MODULE) + {"seeall", ll_seeall}, +#endif + {NULL, NULL} +}; + + +static const luaL_Reg ll_funcs[] = { +#if defined(LUA_COMPAT_MODULE) + {"module", ll_module}, +#endif + {"require", ll_require}, + {NULL, NULL} +}; + + +static void createsearcherstable (lua_State *L) { + static const lua_CFunction searchers[] = + {searcher_preload, searcher_Lua, searcher_C, searcher_Croot, NULL}; + int i; + /* create 'searchers' table */ + lua_createtable(L, sizeof(searchers)/sizeof(searchers[0]) - 1, 0); + /* fill it with pre-defined searchers */ + for (i=0; searchers[i] != NULL; i++) { + lua_pushvalue(L, -2); /* set 'package' as upvalue for all searchers */ + lua_pushcclosure(L, searchers[i], 1); + lua_rawseti(L, -2, i+1); + } +} + + +LUAMOD_API int luaopen_package (lua_State *L) { + /* create table CLIBS to keep track of loaded C libraries */ + luaL_getsubtable(L, LUA_REGISTRYINDEX, CLIBS); + lua_createtable(L, 0, 1); /* metatable for CLIBS */ + lua_pushcfunction(L, gctm); + lua_setfield(L, -2, "__gc"); /* set finalizer for CLIBS table */ + lua_setmetatable(L, -2); + /* create `package' table */ + luaL_newlib(L, pk_funcs); + createsearcherstable(L); +#if defined(LUA_COMPAT_LOADERS) + lua_pushvalue(L, -1); /* make a copy of 'searchers' table */ + lua_setfield(L, -3, "loaders"); /* put it in field `loaders' */ +#endif + lua_setfield(L, -2, "searchers"); /* put it in field 'searchers' */ + /* set field 'path' */ + setpath(L, "path", LUA_PATHVERSION, LUA_PATH, LUA_PATH_DEFAULT); + /* set field 'cpath' */ + setpath(L, "cpath", LUA_CPATHVERSION, LUA_CPATH, LUA_CPATH_DEFAULT); + /* store config information */ + lua_pushliteral(L, LUA_DIRSEP "\n" LUA_PATH_SEP "\n" LUA_PATH_MARK "\n" + LUA_EXEC_DIR "\n" LUA_IGMARK "\n"); + lua_setfield(L, -2, "config"); + /* set field `loaded' */ + luaL_getsubtable(L, LUA_REGISTRYINDEX, "_LOADED"); + lua_setfield(L, -2, "loaded"); + /* set field `preload' */ + luaL_getsubtable(L, LUA_REGISTRYINDEX, "_PRELOAD"); + lua_setfield(L, -2, "preload"); + lua_pushglobaltable(L); + lua_pushvalue(L, -2); /* set 'package' as upvalue for next lib */ + luaL_setfuncs(L, ll_funcs, 1); /* open lib into global table */ + lua_pop(L, 1); /* pop global table */ + return 1; /* return 'package' table */ +} + |