def _read_node(self, node_number, index):
base_offset = node_number * self.metadata.node_byte_size
record_size = self.metadata.record_size
if record_size == 24:
offset = base_offset + index * 3
node_bytes = b'\x00' + self.data[offset:offset + 3]
elif record_size == 28:
(middle,) = struct.unpack(b'!B', self.data[base_offset + 3:base_offset + 4])
if index:
middle &= 0x0F
else:
middle = (0xF0 & middle) >> 4
offset = base_offset + index * 4
node_bytes = byte_from_int(middle) + self.data[offset:offset + 3]
elif record_size == 32:
offset = base_offset + index * 4
node_bytes = self.data[offset:offset + 4]
else:
raise Exception('Unknown record size: {0}'.format(record_size))
return struct.unpack(b'!I', node_bytes)[0]
def _decode_pointer(self, size, offset):
pointer_size = ((size >> 3) & 0x3) + 1
new_offset = offset + pointer_size
pointer_bytes = self._buffer[offset:new_offset]
packed = pointer_bytes if pointer_size == 4 else struct.pack(b"!c", byte_from_int(size & 0x7)) + pointer_bytes
unpacked = int_from_bytes(packed)
pointer = unpacked + self._pointer_base + self._pointer_value_offset[pointer_size]
if self._pointer_test:
return pointer, new_offset
(value, _) = self.decode(pointer)
return value, new_offset
def generate_large_uint(self, bits):
ctrl_byte = b'\x02' if bits == 64 else b'\x03'
uints = {
b'\x00' + ctrl_byte: 0,
b'\x02' + ctrl_byte + b'\x01\xf4': 500,
b'\x02' + ctrl_byte + b'\x2a\x78': 10872,
}
for power in range(bits // 8 + 1):
expected = 2**(8 * power) - 1
input = byte_from_int(power) + ctrl_byte + (b'\xff' * power)
uints[input] = expected
return uints
def generate_large_uint(self, bits):
ctrl_byte = b'\x02' if bits == 64 else b'\x03'
uints = {
b'\x00' + ctrl_byte: 0,
b'\x02' + ctrl_byte + b'\x01\xf4': 500,
b'\x02' + ctrl_byte + b'\x2a\x78': 10872,
}
for power in range(bits // 8 + 1):
expected = 2 ** (8 * power) - 1
input = byte_from_int(power) + ctrl_byte + (b'\xff' * power)
uints[input] = expected
return uints
def generate_large_uint(self, bits):
ctrl_byte = b"\x02" if bits == 64 else b"\x03"
uints = {
b"\x00" + ctrl_byte: 0,
b"\x02" + ctrl_byte + b"\x01\xf4": 500,
b"\x02" + ctrl_byte + b"\x2a\x78": 10872,
}
for power in range(bits // 8 + 1):
expected = 2**(8 * power) - 1
input = byte_from_int(power) + ctrl_byte + (b"\xff" * power)
uints[input] = expected
return uints
def _decode_pointer(self, size, offset):
pointer_size = ((size >> 3) & 0x3) + 1
new_offset = offset + pointer_size
pointer_bytes = self._buffer[offset:new_offset]
packed = pointer_bytes if pointer_size == 4 else struct.pack(
b'!c', byte_from_int(size & 0x7)) + pointer_bytes
unpacked = int_from_bytes(packed)
pointer = unpacked + self._pointer_base + \
self._pointer_value_offset[pointer_size]
if self._pointer_test:
return pointer, new_offset
(value, _) = self.decode(pointer)
return value, new_offset
def _decode_pointer(self, size, offset):
pointer_size = (size >> 3) + 1
buf = self._buffer[offset:offset + pointer_size]
new_offset = offset + pointer_size
if pointer_size == 1:
buf = byte_from_int(size & 0x7) + buf
pointer = struct.unpack(b'!H', buf)[0] + self._pointer_base
elif pointer_size == 2:
buf = b'\x00' + byte_from_int(size & 0x7) + buf
pointer = struct.unpack(b'!I', buf)[0] + 2048 + self._pointer_base
elif pointer_size == 3:
buf = byte_from_int(size & 0x7) + buf
pointer = struct.unpack(b'!I',
buf)[0] + 526336 + self._pointer_base
else:
pointer = struct.unpack(b'!I', buf)[0] + self._pointer_base
if self._pointer_test:
return pointer, new_offset
(value, _) = self.decode(pointer)
return value, new_offset
def test_byte(self):
# Python 2.6 doesn't support dictionary comprehension
b = dict((byte_from_int(0xc0 ^ int_from_byte(k[0])) + k[1:],
v.encode('utf-8')) for k, v in self.strings.items())
self.validate_type_decoding('byte', b)
def test_byte(self):
# Python 2.6 doesn't support dictionary comprehension
b = dict((byte_from_int(0xc0 ^ int_from_byte(k[0])) + k[1:],
v.encode('utf-8'))
for k, v in self.strings.items())
self.validate_type_decoding('byte', b)