bitops.py 文件源码

def write_bytes(self, value, nbytes=None):
        import bitstring
        # TODO: strings are utf-8 from json reading
        if isinstance(value, six.text_type):
            value = value.encode('latin-1')

        value_len = len(value)

        # Ensure the string is under the required data width
        if nbytes is None:
            nbytes = value_len
        else:
            if value_len > nbytes:
                value = value[:nbytes]
            elif value_len < nbytes:
                value += b' ' * (nbytes - value_len)

        # Cannot use string format shortcut, i.e. 'bytes:{}={}' due to the
        # automatic whitespace trimming by bitstring.
        self.bit_stream += bitstring.Bits(bytes=value)
        return value