python socket 定义协议通信 拆包与粘包

    #dataAnalysis from Client

    def dataAnalysis(self):

        datafmt='<IIIIIIII'

        #定义struct 解包格式，相当协议格式

        fmtLen = struct.calcsize(datafmt)

        ＃得到协议长度

        while len(self._buffer) >= fmtLen:

            print "Buffer Length:%s" % len(self._buffer)

            (protocLength,) = \

                struct.unpack('<I',self._buffer[:self.HEADERSIZE])

            ＃取得协议体长度，协议体为protoc

            print protocLength

            if len(self._buffer) == fmtLen+protocLength:

            ＃得到完整协议+协议体

                HeadStr=self._buffer[:fmtLen]

                ＃取出协议

                ProtocStr=self._buffer[fmtLen:fmtLen+protocLength]

                srcStr = struct.unpack(datafmt,HeadStr)

                ＃解包协议格式

                toIP = lambda x: '.'.join([str(x/(256**i)%256) for i in range(3,-1,-1)])

                ＃取得IP地址，由整数转换成IP

                print srcStr

                print 'IP is',toIP(srcStr[6])

                

                print '处理protoc'

                print test1

                self._buffer = self._buffer[fmtLen+protocLength:]

                #分包

            elif len(self._buffer) < fmtLen+protocLength:

                print "Continue Received"

                return

            else:

                print "Error"

                self.transport.loseConnection()

                return