状态机 代表Locked , Closed和Open门的示例状态机。 在每种状态下,都可以尝试使用“锁”或“手柄” 。 Current State | Try | Next State | --------------|--------|------------| Locked | Lock | Closed | Locked | Handle | ERROR! | Closed | Lock | Locked | Closed | Handle | Open | Open | Lock | ERROR! | Open | Handle | Closed | 驱动程序 C代码 struct door *door = do