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#!/usr/bin/env python

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# -*- coding: utf-8 -*-

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# This file is part of Beremiz, a Integrated Development Environment for

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# programming IEC 61131-3 automates supporting plcopen standard and CanFestival.

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#

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# Copyright (C) 2007: Edouard TISSERANT and Laurent BESSARD

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#

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# See COPYING file for copyrights details.

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#

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# This program is free software; you can redistribute it and/or

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# modify it under the terms of the GNU General Public License

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# as published by the Free Software Foundation; either version 2

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# of the License, or (at your option) any later version.

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#

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# This program is distributed in the hope that it will be useful,

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# but WITHOUT ANY WARRANTY; without even the implied warranty of

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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

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# GNU General Public License for more details.

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#

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# You should have received a copy of the GNU General Public License

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# along with this program; if not, write to the Free Software

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# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

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import socket, threading

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from util import Zeroconf

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service_type = '_PYRO._tcp.local.'

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class ServicePublisher():

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    def __init__(self):

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        # type: fully qualified service type name

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        self.serviceproperties = {'description':'Beremiz remote PLC'}

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        self.name = None

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        self.ip_32b = None

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        self.port = None

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        self.server = None

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        self.service_name = None

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        self.retrytimer = None

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    def RegisterService(self, name, ip, port):

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        try:

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            self._RegisterService(name, ip, port)

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        except Exception,e:

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            self.retrytimer = threading.Timer(2,self.RegisterService,[name, ip, port])

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            self.retrytimer.start() 

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    def _RegisterService(self, name, ip, port):

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        # name: fully qualified service name

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        self.service_name = 'Beremiz_%s.%s'%(name,service_type)

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        self.name = name

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        self.port = port

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        self.server = Zeroconf.Zeroconf(ip)

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        print "MDNS brodcasting on :"+ip

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        if ip == "0.0.0.0":

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            ip = self.gethostaddr()

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        print "MDNS brodcasted service address :"+ip

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        self.ip_32b = socket.inet_aton(ip)

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        self.server.registerService(

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             Zeroconf.ServiceInfo(service_type,

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                                  self.service_name,

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                                  self.ip_32b,

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                                  self.port,

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                                  properties = self.serviceproperties))

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        self.retrytimer=None

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    def UnRegisterService(self):

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        if self.retrytimer is not None:

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            self.retrytimer.cancel()

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        self.server.unregisterService(

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                                      Zeroconf.ServiceInfo(service_type, 

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                                                           self.service_name, 

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                                                           self.ip_32b, 

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                                                           self.port, 

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                                                           properties = self.serviceproperties))

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        self.server.close()

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        self.server = None

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    def gethostaddr(self, dst = '224.0.1.41'):

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        s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)

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        try:

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            s.connect((dst, 7))

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            (host, port) = s.getsockname()

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            s.close()

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            if host != '0.0.0.0':

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                return host

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        except Exception,e:

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            pass

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        return socket.gethostbyname(socket.gethostname())