def test_endianness(self):
"""
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| h.version | h.type | h.flags | <reserved> |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
"""
one = 1
one_little_endian = one.to_bytes(4, 'little')
one_big_endian = one.to_bytes(4, 'big')
# flag unset
pdu_little_endian = PDUHeader.from_bytes(b'\x00\x00\x00\x00' + one_little_endian * 4)
self.assertEqual(pdu_little_endian.session_id, 1)
self.assertEqual(pdu_little_endian.transaction_id, 1)
self.assertEqual(pdu_little_endian.packet_id, 1)
self.assertEqual(pdu_little_endian.payload_length, 1)
print(pdu_little_endian)
nbo_set = struct.pack('!BBBB', 0, 0, 0 | PDUHeaderTags.MASK_NEWORK_BYTE_ORDER, 0)
# network byte flag set
pdu_big_endian = PDUHeader.from_bytes(nbo_set + one_big_endian * 4)
self.assertEqual(pdu_big_endian.session_id, 1)
self.assertEqual(pdu_big_endian.transaction_id, 1)
self.assertEqual(pdu_big_endian.packet_id, 1)
self.assertEqual(pdu_big_endian.payload_length, 1)
print(pdu_big_endian)
def test_bad_unpack(self):
with self.assertRaises(exceptions.PDUUnpackError):
# missing IDs
PDUHeader.from_bytes(b'\x00\x00\x00\x00')
with self.assertRaises(exceptions.PDUUnpackError):
# missing payload length
PDUHeader.from_bytes(b'\x00\x00\x00\x00' * 3)
