def read_block(cls, fh, start):
fh.seek(start)
magic = fh.read(cls.SIZE_MAGIC)
if magic != cls.MAGIC_BYTES:
raise PyDBInternalError(
"Not a block at start position: {}.".format(start))
size = bytes_to_int(fh.read(cls.SIZE_SIZE))
nxt = bytes_to_int(fh.read(cls.SIZE_NEXT))
prev = bytes_to_int(fh.read(cls.SIZE_PREV))
next_empty = bytes_to_int(fh.read(cls.SIZE_NEXT_EMPTY))
return cls(start, size, nxt, prev, next_empty=next_empty)
def test_bytes_to_int():
assert bytes_to_int(b'){\x8a\x83\xdc\x03O\x8e') == 2989135076627009422
def read_header(self):
self.io.seek(0)
self.count = bytes_to_int(self.io.read(self.SIZE_HEADER))
def decode_header(cls, barr):
arr = b''.join(islice(barr, 0, TypeHeader.SIZE_TOTAL))
null = bytes_to_int(arr[0:cls.SIZE_NULL])
size = bytes_to_int(arr[cls.SIZE_NULL:cls.SIZE_NULL + cls.SIZE_SIZE])
return TypeHeader(null, size)
def decode_value(self, val):
return bytes_to_int(val)
def read_structure(self, fh, header_structure):
self.header.seek(0)
it = self.header.iterdata(chunk_size=4)
it = ((a, b, bytes_to_int(c)) for a, b, c in it)
super_blocks_pos = [x[2] for x in takewhile(lambda x: x[2] != -1, it)]
return [BlockStructure(fh, x) for x in super_blocks_pos]