LUA_API int lua_getuservalue (lua_State *L, int idx) {
StkId o;
lua_lock(L);
o = index2addr(L, idx);
api_check(ttisfulluserdata(o), "full userdata expected");
getuservalue(L, uvalue(o), L->top);
api_incr_top(L);
lua_unlock(L);
return ttnov(L->top - 1);
}
/*
** Return the name of the type of an object. For tables and userdata
** with metatable, use their '__name' metafield, if present.
*/
const char *luaT_objtypename (lua_State *L, const TValue *o) {
Table *mt;
if ((ttistable(o) && (mt = hvalue(o)->metatable) != NULL) ||
(ttisfulluserdata(o) && (mt = uvalue(o)->metatable) != NULL)) {
const TValue *name = luaH_getshortstr(mt, luaS_new(L, "__name"));
if (ttisstring(name)) /* is '__name' a string? */
return getstr(tsvalue(name)); /* use it as type name */
}
return ttypename(ttype(o)); /* else use standard type name */
}
LUA_API void lua_setuservalue (lua_State *L, int idx) {
StkId o;
lua_lock(L);
api_checknelems(L, 1);
o = index2addr(L, idx);
api_check(ttisfulluserdata(o), "full userdata expected");
setuservalue(L, uvalue(o), L->top - 1);
luaC_barrier(L, gcvalue(o), L->top - 1);
L->top--;
lua_unlock(L);
}
LUA_API int lua_isuserdata (lua_State *L, int idx) {
const TValue *o = index2addr(L, idx);
return (ttisfulluserdata(o) || ttislightuserdata(o));
}
