python - 聊天室服务器在 SIGINT 时未关闭线程且未退出

问题描述

我在 Python 中有以下模拟聊天室的服务器程序。该代码接受来自客户端的连接，并为每个客户端启动一个新线程。该线程将等待来自该客户端的消息。消息可以L使服务器响应连接的客户端列表，ip:port msg服务器将消息发送msg给客户端ip:port。

在客户端将有 2 个线程，一个用于从服务器接收消息，另一个用于发送。

import socket
from threading import Thread
#from SocketServer import ThreadingMixIn
import signal
import sys
import errno

EXIT = False
address = []
address2 = []

# handler per il comando Ctrl+C
def sig_handler(signum, frame):
    if (signum == 2):
        print("Called SIGINT")
        EXIT = True

signal.signal(signal.SIGINT, sig_handler) # setto l'handler per i segnali


# Multithreaded Python server : TCP Server Socket Thread Pool
class ClientThread(Thread):

    def __init__(self,conn,ip,port):
        Thread.__init__(self)
        self.conn = conn
        self.ip = ip
        self.port = port
        print ("[+] New server socket thread started for " + ip + ":" + str(port))
    def run(self):
        while True:
            data = self.conn.recv(1024)
            print ("Server received data:", data)
            if (data=='L'):
                #print "QUI",address2
                tosend = ""
                for i in address2:
                    tosend = tosend + "ip:"+str(i[0]) + "port:"+str(i[1])+"\n"
                self.conn.send(tosend)
                #mandare elenco client connessi
            else:
                #manda ip:port msg
                st = data.split(" ")
                msg = st[1:]
                msg = ' '.join(msg)
                print ("MSG 2 SEND: ",msg)
                ipport = st[0].split(":")
                ip = ipport[0]
                port = ipport[1]
                flag = False
                print ("Address2:",address2)
                print ("ip:",ip)
                print ("port:",port)
                for i in address2:
                    print (i[0],ip,type(i[0]),type(ip),i[1],type(i[1]),port,type(port))
                    if str(i[0])==str(ip) and str(i[1])==str(port):
                        i[2].send(msg)
                        self.conn.send("msg inviato")
                        flag = True
                        break
                if flag == False:
                    self.conn.send("client non esistente")


if __name__ == '__main__':
    # Multithreaded Python server : TCP Server Socket Program Stub
    TCP_IP = '127.0.0.1'
    TCP_PORT = 2004
    TCP_PORTB = 2005
    BUFFER_SIZE = 1024  # Usually 1024, but we need quick response

    tcpServer = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    tcpServer.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
    tcpServer.bind((TCP_IP, TCP_PORT))

    tcpServerB = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    tcpServerB.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
    tcpServerB.bind((TCP_IP, TCP_PORTB))
    threads = []

    tcpServer.listen(4)
    tcpServerB.listen(4)

    while True:
        print("Multithreaded Python server : Waiting for connections from TCP clients...")
        try:
            (conn, (ip,port)) = tcpServer.accept()
        except socket.error as e: #(code, msg):
            if e.errno != errno.EINTR:
                raise
            else:
                break
        address.append((ip,port,conn))

        (conn2, (ip2,port2)) = tcpServerB.accept()
        address2.append((ip2,port2,conn2))

        newthread = ClientThread(conn,ip,port)
        newthread.start()
        threads.append(newthread)
        if EXIT==True:
            break

    print ("SERVER EXIT")

    for t in threads:
        t.join()

该代码有一个信号处理程序，SIGINT用于使退出更清晰（关闭连接，向客户端发送消息（仍有待实现）等等）。处理程序写入一个全局标志EXIT以使无限循环终止。

代码在 Python2 和 Python3 中运行。SIGINT但是CTRL-C 生成的信号存在一些问题。当没有客户端连接时，使用 Python2 启动的程序会正确退出，而 Python3 中的程序则不会。为什么会有这种行为差异？
考虑只在 Python2 中运行程序，当客户端连接并且我按下 CTRL-C 时，main while 退出，就像信号总是被主线程捕获，这会中断阻塞的系统调用accept。但是其他线程没有，我认为是因为阻塞了底层系统调用data = self.conn.recv(1024)。在 CI 中会阻塞SIGINT一个线程的信号，然后pthread_cancel从另一个线程调用。SIGINT在Python中生成时如何退出所有线程？

目前仅在 Python2 中工作并遇到相同问题的客户端程序是：

# Python TCP Client A
import socket
from threading import Thread

class ClientThread(Thread):

    def __init__(self,conn):
        Thread.__init__(self)
        self.conn = conn

    def run(self):
        while True:
            data = self.conn.recv(1024)
            print "Ricevuto msg:",data

host = socket.gethostname()
print "host:",host
port = 2004
portB = 2005
BUFFER_SIZE = 2000

tcpClientA = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
tcpClientB = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
tcpClientA.connect(('127.0.0.1', port))
tcpClientB.connect(('127.0.0.1', portB))

newthread = ClientThread(tcpClientB)
newthread.start()


while(True):
    msg = raw_input("Inserisci comando: ")
    tcpClientA.send (msg)
    data = tcpClientA.recv(BUFFER_SIZE)
    print "data received:",data

tcpClientA.close()

标签： pythonpython-3.xserversignalspython-2.x

python - 聊天室服务器在 SIGINT 时未关闭线程且未退出

问题描述

解决方案

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