can_ethernet.py 文件源码

def Connect(self):
    self.socket_mode = UDP_MODE
    self.mac = uuid.getnode()

    # Set up UDP receiver.
    self.udp_rx_sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
    self.udp_rx_sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)

    # Pack multicast group structure correctly.
    mreq = struct.pack('=4sl', socket.inet_aton(MCAST_GRP),socket.INADDR_ANY) 

    # Request access to multicast group.
    self.udp_rx_sock.setsockopt(socket.IPPROTO_IP,
                                socket.IP_ADD_MEMBERSHIP, mreq)  

    # Bind to all intfs.
    self.udp_rx_sock.bind(('', MCAST_PORT))
    self.udp_rx_sock.settimeout(TIMEOUT)

    # Set up UDP transmitter.
    self.udp_tx_sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
    self.udp_tx_sock.setsockopt(socket.IPPROTO_IP, socket.IP_MULTICAST_TTL, 255)

    # Get the MAC address of the local adapter.
    msg = bytearray(8)
    struct.pack_into('<Q', msg, 0, int(self.mac))
    self.local_mac = ''.join('{:02x}'.format(x) for x in msg[0:6])
    logging.debug('MAC Addr: %s', self.local_mac)