65 lines
2.5 KiB
Python
65 lines
2.5 KiB
Python
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import socket
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import threading
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class VoltageReceiver():
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def __init__(self):
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self.data = "" # 数据存储
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self.active = False # 控制线程的开关
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self.dataready = 0 # 数据是否准备好的标志位
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self.thread = None # 线程存储
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self.sock = None # 套接字存储
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def receive_data(self):
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self.sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
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self.sock.bind(('localhost', 9996))
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self.sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
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self.sock.listen(1)
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while self.active: # 只有当 self.active 为 True 时，才开始监听
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conn, addr = self.sock.accept()
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while conn:
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try:
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data = conn.recv(1024)
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except socket.error as e:
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print("Remote host has disconnected.") # 打印提醒
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break
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if not data or not self.active: # 如果没有数据或 self.active 为 False， 则跳出循环
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break
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data = data.decode()
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if self.dataready:
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# 新的数据已经准备好，而旧的数据还没被取走，发出警告
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self.alert()
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with threading.Lock(): # 使用锁确保线程安全
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self.data = data
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self.dataready = 1
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conn.close()
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def start(self): # 开始监听
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if not self.thread or not self.thread.is_alive(): # 如果线程未创建或已结束，那么创建一个新线程
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self.active = True
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self.thread = threading.Thread(target=self.receive_data)
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self.thread.start()
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def stop(self): # 停止监听
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self.active = False
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if self.sock: # 关闭套接字，使得 sock.accept() 退出阻塞
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self.sock.close()
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def get_data(self): # 获取数据
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with threading.Lock(): # 使用锁确保线程安全
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self.dataready = 0
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return self.data
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def alert(self): # 报警函数
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print("Warning: New data has arrived but the old data has not been taken away.")
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if __name__ == "__main__": # 测试代码
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receiver = VoltageReceiver() # 创建一个 VoltageReceiver 的实例
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receiver.start() # 开始监听
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while receiver.active:
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if receiver.dataready: # 当数据准备好时，打印数据
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print(receiver.get_data())
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receiver.stop() # 停止监听
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