lsf.py 文件源码

def read_message(self):
        """
        Returns a generator that yields the messages in the currently open LSF file.
        This requires the LSFReader object to be opened using the "with" statement.
        See read(), where this is done automatically.
        :return:
        """

        if self.idx:
            # Read using index
            for pos in self.sorted_idx_iter(self.msg_types):
                self.f.seek(pos)
                self.peek_header()
                self.parser.reset()
                b = self.f.read(self.header.size + ctypes.sizeof(IMCHeader) + ctypes.sizeof(IMCFooter))
                msg = self.parser.parse(b)
                yield msg
        else:
            # Read file without index
            # Check for file end
            while self.f.peek(1):
                self.peek_header()

                if not self.msg_types or self.header.mgid in self.msg_types:
                    self.parser.reset()
                    b = self.f.read(self.header.size + ctypes.sizeof(IMCHeader) + ctypes.sizeof(IMCFooter))
                    msg = self.parser.parse(b)
                    yield msg
                else:
                    self.f.seek(ctypes.sizeof(IMCHeader) + self.header.size + ctypes.sizeof(IMCFooter), io.SEEK_CUR)