static int ll_module (lua_State *L) {
const char *modname = luaL_checkstring(L, 1);
int loaded;
if (luaR_findglobal(modname, strlen(modname)))
return 0;
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;
}
LUALIB_API const char *luaL_findtable (lua_State *L, int idx,
const char *fname, int szhint) {
const char *e;
lua_pushvalue(L, idx);
do {
e = c_strchr(fname, '.');
if (e == NULL) e = fname + c_strlen(fname);
lua_pushlstring(L, fname, e - fname);
lua_rawget(L, -2);
if (lua_isnil(L, -1)) {
/* If looking for a global variable, check the rotables too */
void *ptable = luaR_findglobal(fname, e - fname);
if (ptable) {
lua_pop(L, 1);
lua_pushrotable(L, ptable);
}
}
if (lua_isnil(L, -1)) { /* no such field? */
lua_pop(L, 1); /* remove this nil */
lua_createtable(L, 0, (*e == '.' ? 1 : szhint)); /* new table for field */
lua_pushlstring(L, fname, e - fname);
lua_pushvalue(L, -2);
lua_settable(L, -4); /* set new table into field */
}
else if (!lua_istable(L, -1) && !lua_isrotable(L, -1)) { /* field has a non-table value? */
lua_pop(L, 2); /* remove table and value */
return fname; /* return problematic part of the name */
}
lua_remove(L, -2); /* remove previous table */
fname = e + 1;
} while (*e == '.');
return NULL;
}
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 */
}
/* Is this a readonly table? */
{
void *res = luaR_findglobal(name, strlen(name));
if (res) {
lua_pushrotable(L, res);
return 1;
}
}
/* 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;
}
static int luaB_index(lua_State *L) {
#if LUA_OPTIMIZE_MEMORY == 2
int fres;
if ((fres = luaR_findfunction(L, base_funcs_list)) != 0)
return fres;
#endif
const char *keyname = luaL_checkstring(L, 2);
if (!c_strcmp(keyname, "_VERSION")) {
lua_pushliteral(L, LUA_VERSION);
return 1;
}
void *res = luaR_findglobal(keyname, c_strlen(keyname));
if (!res)
return 0;
else {
lua_pushrotable(L, res);
return 1;
}
}
