drgn/tests/test_serialize.py
2019-04-11 15:51:20 -07:00

64 lines
2.4 KiB
Python

import unittest
from tests.libdrgn import deserialize_bits, serialize_bits
VALUE = 12345678912345678989
def py_serialize_bits(value, bit_offset, bit_size, little_endian):
bits = bit_offset + bit_size
size = (bits + 7) // 8
if little_endian:
tmp = value << bit_offset
else:
tmp = value << -bits % 8
# Buffer with unused bits set to zero.
buf0 = tmp.to_bytes(size, 'little' if little_endian else 'big')
# Buffer with unused bits set to one.
buf1 = bytearray(buf0)
if little_endian:
# bit_offset least significant bits.
buf1[0] |= (1 << bit_offset) - 1
# 8 - (bit_offset + bit_size) % 8 most significant bits.
buf1[-1] |= (0xff00 >> -bits % 8) & 0xff
else:
# bit_offset most significant bits.
buf1[0] |= (0xff00 >> bit_offset) & 0xff
# 8 - (bit_offset + bit_size) % 8 least significant bits.
buf1[-1] |= (1 << -bits % 8) - 1
return buf0, buf1
class TestSerialize(unittest.TestCase):
def test_deserialize(self):
for bit_size in range(1, 65):
expected = VALUE & ((1 << bit_size) - 1)
for bit_offset in range(8):
for little_endian in [True, False]:
for buf in py_serialize_bits(expected, bit_offset,
bit_size, little_endian):
value = deserialize_bits(buf, bit_offset, bit_size,
little_endian)
self.assertEqual(value, expected)
def test_serialize(self):
for bit_size in range(1, 65):
value = VALUE & ((1 << bit_size) - 1)
for bit_offset in range(8):
for little_endian in [True, False]:
expected0, expected1 = py_serialize_bits(value, bit_offset,
bit_size,
little_endian)
buf = bytearray(len(expected0))
serialize_bits(buf, bit_offset, value, bit_size,
little_endian)
self.assertEqual(buf, expected0)
buf = bytearray([0xff] * len(expected1))
serialize_bits(buf, bit_offset, value, bit_size,
little_endian)
self.assertEqual(buf, expected1)