reflector.py

import select
import socket
import sys

server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
server_socket.setblocking(0)

myport = int(sys.argv[1])
server_socket.bind(('0.0.0.0', myport))

sockets = [server_socket]
mirror_connections = {}

server_socket.listen(10)

while True:
    rfds, _wfds, xfds = select.select(sockets, [], sockets, 1)
    print rfds, _wfds, xfds
    for rfd in rfds:
        if server_socket == rfd:
            conn, addr = server_socket.accept()
            s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
            try:
                s.connect((addr[0], myport))
                sockets.append(s)
                sockets.append(conn)
                mirror_connections[s] = conn
                mirror_connections[conn] = s
            except Exception, e:
                conn.close()
        else:
            buf = rfd.recv(4096)
            if len(buf) == 0:
                print 'conn closed'
                mirror_conn = mirror_connections[rfd]
                sockets.remove(rfd)
                sockets.remove(mirror_conn)
                mirror_conn.close()
                rfd.close()
                del mirror_connections[mirror_conn]
                del mirror_connections[rfd]
                continue
            mirror_connections[rfd].send(buf)