common_func.py 文件源码

def _start(self):
        # memoryview act as an recv buffer
        # refer https://docs.python.org/3/library/stdtypes.html#memoryview
        buff = memoryview(bytearray(RECV_BUFFER_SIZE))
        while True:
            if not self.conn_rd:
                # sleep if there is no connections
                time.sleep(0.06)
                continue

            # blocks until there is socket(s) ready for .recv
            # notice: sockets which were closed by remote,
            #   are also regarded as read-ready by select()
            r, w, e = select.select(self.conn_rd, [], [], 0.5)

            for s in r:  # iter every read-ready or closed sockets
                try:
                    # here, we use .recv_into() instead of .recv()
                    #   recv data directly into the pre-allocated buffer
                    #   to avoid many unnecessary malloc()
                    # see https://docs.python.org/3/library/socket.html#socket.socket.recv_into
                    rec_len = s.recv_into(buff, RECV_BUFFER_SIZE)
                except:
                    # unable to read, in most cases, it's due to socket close
                    self._rd_shutdown(s)
                    continue

                if not rec_len:
                    # read zero size, closed or shutdowned socket
                    self._rd_shutdown(s)
                    continue

                try:
                    # send data, we use `buff[:rec_len]` slice because
                    #   only the front of buff is filled
                    self.map[s].send(buff[:rec_len])
                except:
                    # unable to send, close connection
                    self._rd_shutdown(s)
                    continue