Golang C.lua

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func (self *Lua) RegisterFunction(name string, fun interface{}) {
	path := strings.Split(name, ".")
	name = path[len(path)-1]
	path = path[0 : len(path)-1]
	if len(path) == 0 {
		path = append(path, "_G")
	}

	// ensure namespaces
	for i, namespace := range path {
		cNamespace := cstr(namespace)
		if i == 0 { // top namespace
			what := C.lua_getglobal(self.State, cNamespace)
			if what == C.LUA_TNIL { // not exists
				C.lua_settop(self.State, -2)
				C.lua_createtable(self.State, 0, 0)
				C.lua_setglobal(self.State, cNamespace)
				C.lua_getglobal(self.State, cNamespace)
			}
			if C.lua_type(self.State, -1) != C.LUA_TTABLE {
				self.Panic("global %s is not a table", namespace)
			}
		} else { // sub namespace
			C.lua_pushstring(self.State, cNamespace)
			C.lua_rawget(self.State, -2)
			if C.lua_type(self.State, -1) == C.LUA_TNIL {
				C.lua_settop(self.State, -2)
				C.lua_pushstring(self.State, cNamespace)
				C.lua_createtable(self.State, 0, 0)
				C.lua_rawset(self.State, -3)
				C.lua_pushstring(self.State, cNamespace)
				C.lua_rawget(self.State, -2)
			}
			if C.lua_type(self.State, -1) != C.LUA_TTABLE {
				self.Panic("namespace %s is not a table", namespace)
			}
		}
	}

	// register function
	funcType := reflect.TypeOf(fun)
	if funcType.IsVariadic() {
		self.Panic("cannot register variadic function: %v", fun)
	}
	argc := funcType.NumIn()
	cName := cstr(name)
	function := &Function{
		fun:       fun,
		lua:       self,
		name:      name,
		funcType:  funcType,
		funcValue: reflect.ValueOf(fun),
		argc:      argc,
	}
	funcId := rand.Int63()
	functionRegister.Set(funcId, function)
	C.register_function(self.State, cName, (C.int64_t)(funcId))
	self.Functions[name] = function
	C.lua_settop(self.State, -2)
}

// Peval evaluates a piece of lua code. no panic when error occur.
func (l *Lua) Peval(code string, envs ...interface{}) (returns []interface{}, err error) {
	defer C.lua_settop(l.State, 0)
	C.push_errfunc(l.State)
	curTop := C.lua_gettop(l.State)
	// parse
	cCode := C.CString(code)
	defer C.free(unsafe.Pointer(cCode))
	if ret := C.luaL_loadstring(l.State, cCode); ret != 0 { // load error
		return nil, fmt.Errorf("LOAD ERROR: %s", C.GoString(C.lua_tolstring(l.State, -1, nil)))
	}
	// env
	if len(envs) > 0 {
		if len(envs)%2 != 0 {
			return nil, fmt.Errorf("number of arguments not match")
		}
		C.lua_createtable(l.State, 0, 0)
		for i := 0; i < len(envs); i += 2 {
			name, ok := envs[i].(string)
			if !ok {
				return nil, fmt.Errorf("name must be string, not %v", envs[i])
			}
			C.lua_pushstring(l.State, cstr(name))
			err := l.pushGoValue(envs[i+1], name)
			if err != nil {
				return nil, err
			}
			C.lua_rawset(l.State, -3)
		}
		// set env
		C.set_eval_env(l.State)
	}
	// call
	l.err = nil
	if ret := C.lua_pcall(l.State, 0, C.LUA_MULTRET, -2); ret != 0 {
		// error occured
		return nil, fmt.Errorf("CALL ERROR: %s", C.GoString(C.lua_tolstring(l.State, -1, nil)))
	} else if l.err != nil { // error raise by invokeGoFunc
		return nil, l.err
	} else {
		// return values
		nReturn := C.lua_gettop(l.State) - curTop
		returns = make([]interface{}, int(nReturn))
		for i := C.int(0); i < nReturn; i++ {
			value, err := l.toGoValue(-1-i, interfaceType)
			if err != nil {
				return nil, err
			}
			if value != nil {
				returns[int(nReturn-1-i)] = value.Interface()
			} else {
				returns[int(nReturn-1-i)] = nil
			}
		}
	}
	return
}

func (l *Lua) set(fullname string, v interface{}) error {
	// ensure name
	errMsg := C.ensure_name(l.State, C.CString(fullname))
	if errMsg != nil {
		return fmt.Errorf("%s: %s", errMsg, fullname)
	}

	// push value
	err := l.pushGoValue(v, fullname)
	if err != nil {
		return err
	}

	// set
	C.lua_rawset(l.State, -3)
	// clear stack
	C.lua_settop(l.State, 0)

	return nil
}

// lua_rawset
func (L *State) RawSet(index int) {
	C.lua_rawset(L.s, C.int(index))
}

// Similar to Settable, but does a raw assignment (i.e., without
// metamethods).
func (this *State) Rawset(index int) {
	C.lua_rawset(this.luastate, C.int(index))
}

// Similar to Settable, but does a raw assignment (i.e., without
// metamethods).
func (s *State) Rawset(index int) {
	C.lua_rawset(s.l, C.int(index))
}

func Rawset(s *State, index int) {
	C.lua_rawset((*C.lua_State)(s), C.int(index))
}