fclose(f);  return 1;}static const char *pushnexttemplate (lua_State *L, const char *path) {  const char *l;  while (*path == *LUA_PATHSEP) path++;  /* skip separators */  if (*path == '\0') return NULL;  /* no more templates */  l = strchr(path, *LUA_PATHSEP);  /* find next separator */  if (l == NULL) l = path + strlen(path);  lua_pushlstring(L, path, l - path);  /* template */  return l;}static const char *findfile (lua_State *L, const char *name,                                           const char *pname) {  const char *path;  name = luaL_gsub(L, name, ".", LUA_DIRSEP);  lua_getfield(L, LUA_ENVIRONINDEX, pname);  path = lua_tostring(L, -1);  if (path == NULL)    luaL_error(L, LUA_QL("package.%s") " must be a string", pname);  lua_pushliteral(L, "");  /* error accumulator */  while ((path = pushnexttemplate(L, path)) != NULL) {    const char *filename;    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 */    lua_concat(L, 2);  /* add entry to possible error message */  }  return NULL;  /* not found */}static void loaderror (lua_State *L, const char *filename) {  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 loader_Lua (lua_State *L) {  const char *filename;  const char *name = luaL_checkstring(L, 1);  filename = findfile(L, name, "path");  if (filename == NULL) return 1;  /* library not found in this path */  if (luaL_loadfile(L, filename) != 0)    loaderror(L, filename);  return 1;  /* library loaded successfully */}static const char *mkfuncname (lua_State *L, const char *modname) {  const char *funcname;  const char *mark = strchr(modname, *LUA_IGMARK);  if (mark) modname = mark + 1;  funcname = luaL_gsub(L, modname, ".", LUA_OFSEP);  funcname = lua_pushfstring(L, POF"%s", funcname);  lua_remove(L, -2);  /* remove 'gsub' result */  return funcname;}static int loader_C (lua_State *L) {  const char *funcname;  const char *name = luaL_checkstring(L, 1);  const char *filename = findfile(L, name, "cpath");  if (filename == NULL) return 1;  /* library not found in this path */  funcname = mkfuncname(L, name);  if (ll_loadfunc(L, filename, funcname) != 0)    loaderror(L, filename);  return 1;  /* library loaded successfully */}static int loader_Croot (lua_State *L) {  const char *funcname;  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");  if (filename == NULL) return 1;  /* root not found */  funcname = mkfuncname(L, name);  if ((stat = ll_loadfunc(L, filename, funcname)) != 0) {    if (stat != ERRFUNC) loaderror(L, filename);  /* real error */    lua_pushfstring(L, "\n\tno module " LUA_QS " in file " LUA_QS,                       name, filename);    return 1;  /* function not found */  }  return 1;}static int loader_preload (lua_State *L) {  const char *name = luaL_checkstring(L, 1);  lua_getfield(L, LUA_ENVIRONINDEX, "preload");  if (!lua_istable(L, -1))    luaL_error(L, LUA_QL("package.preload") " must be a table");  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 const int sentinel_ = 0;#define sentinel	((void *)&sentinel_)static int ll_require (lua_State *L) {  const char *name = luaL_checkstring(L, 1);  int i;  lua_settop(L, 1);  /* _LOADED table will be at index 2 */  lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");  lua_getfield(L, 2, name);  if (lua_toboolean(L, -1)) {  /* is it there? */    if (lua_touserdata(L, -1) == sentinel)  /* check loops */      luaL_error(L, "loop or previous error loading module " LUA_QS, name);    return 1;  /* package is already loaded */  }  /* else must load it; iterate over available loaders */  lua_getfield(L, LUA_ENVIRONINDEX, "loaders");  if (!lua_istable(L, -1))    luaL_error(L, LUA_QL("package.loaders") " must be a table");  lua_pushliteral(L, "");  /* error message accumulator */  for (i=1; ; i++) {    lua_rawgeti(L, -2, i);  /* get a loader */    if (lua_isnil(L, -1))      luaL_error(L, "module " LUA_QS " not found:%s",                    name, lua_tostring(L, -2));    lua_pushstring(L, name);    lua_call(L, 1, 1);  /* call it */    if (lua_isfunction(L, -1))  /* did it find module? */      break;  /* module loaded successfully */    else if (lua_isstring(L, -1))  /* loader returned error message? */      lua_concat(L, 2);  /* accumulate it */    else      lua_pop(L, 1);  }  lua_pushlightuserdata(L, sentinel);  lua_setfield(L, 2, name);  /* _LOADED[name] = sentinel */  lua_pushstring(L, name);  /* pass name as argument to module */  lua_call(L, 1, 1);  /* run loaded 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_touserdata(L, -1) == sentinel) {   /* 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** =======================================================*/  static void setfenv (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);  lua_setfenv(L, -2);  lua_pop(L, 1);}static void dooptions (lua_State *L, int n) {  int i;  for (i = 2; i <= n; i++) {    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 loaded = lua_gettop(L) + 1;  /* index of _LOADED table */  lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");  lua_getfield(L, loaded, modname);  /* get _LOADED[modname] */  if (!lua_istable(L, -1)) {  /* not found? */    lua_pop(L, 1);  /* remove previous result */    /* try global variable (and create one if it does not exist) */    if (luaL_findtable(L, LUA_GLOBALSINDEX, modname, 1) != NULL)      return luaL_error(L, "name conflict for module " LUA_QS, modname);    lua_pushvalue(L, -1);    lua_setfield(L, loaded, modname);  /* _LOADED[modname] = new 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);  setfenv(L);  dooptions(L, loaded - 1);  return 0;}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_pushvalue(L, LUA_GLOBALSINDEX);  lua_setfield(L, -2, "__index");  /* mt.__index = _G */  return 0;}/* }====================================================== *//* auxiliary mark (for internal use) */#define AUXMARK		"\1"static void setpath (lua_State *L, const char *fieldname, const char *envname,                                   const char *def) {  const char *path = getenv(envname);  if (path == NULL)  /* 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_PATHSEP LUA_PATHSEP,                              LUA_PATHSEP AUXMARK LUA_PATHSEP);    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},  {"seeall", ll_seeall},  {NULL, NULL}};static const luaL_Reg ll_funcs[] = {  {"module", ll_module},  {"require", ll_require},  {NULL, NULL}};static const lua_CFunction loaders[] =  {loader_preload, loader_Lua, loader_C, loader_Croot, NULL};LUALIB_API int luaopen_package (lua_State *L) {  int i;  /* create new type _LOADLIB */  luaL_newmetatable(L, "_LOADLIB");  lua_pushcfunction(L, gctm);  lua_setfield(L, -2, "__gc");  /* create `package' table */  luaL_register(L, LUA_LOADLIBNAME, pk_funcs);#if defined(LUA_COMPAT_LOADLIB)   lua_getfield(L, -1, "loadlib");  lua_setfield(L, LUA_GLOBALSINDEX, "loadlib");#endif  lua_pushvalue(L, -1);  lua_replace(L, LUA_ENVIRONINDEX);  /* create `loaders' table */  lua_createtable(L, 0, sizeof(loaders)/sizeof(loaders[0]) - 1);  /* fill it with pre-defined loaders */  for (i=0; loaders[i] != NULL; i++) {    lua_pushcfunction(L, loaders[i]);    lua_rawseti(L, -2, i+1);  }  lua_setfield(L, -2, "loaders");  /* put it in field `loaders' */  setpath(L, "path", LUA_PATH, LUA_PATH_DEFAULT);  /* set field `path' */  setpath(L, "cpath", LUA_CPATH, LUA_CPATH_DEFAULT); /* set field `cpath' */  /* store config information */  lua_pushliteral(L, LUA_DIRSEP "\n" LUA_PATHSEP "\n" LUA_PATH_MARK "\n"                     LUA_EXECDIR "\n" LUA_IGMARK);  lua_setfield(L, -2, "config");  /* set field `loaded' */  luaL_findtable(L, LUA_REGISTRYINDEX, "_LOADED", 2);  lua_setfield(L, -2, "loaded");  /* set field `preload' */  lua_newtable(L);  lua_setfield(L, -2, "preload");  lua_pushvalue(L, LUA_GLOBALSINDEX);  luaL_register(L, NULL, ll_funcs);  /* open lib into global table */  lua_pop(L, 1);  return 1;  /* return 'package' table */}