def decode_block(self, data, size):
if size > len(data):
size = len(data)
done = 0
block = ContentBlock()
while done < size:
start = done
if data[done] == 0xdd:
cidlen, done = valuecodecs.parse_varuint(data, done+1)
sumlen, done = valuecodecs.parse_varuint(data, done)
cid = data[done:done+cidlen]
cksum = data[done:done+sumlen]
done += max(cidlen, sumlen)
first = (
data[done] + data[done+1] * 0x100 +
data[done+2] * 0x10000 + data[done+3] * 0x1000000)
done += 4
last = (
data[done] + data[done+1] * 0x100 +
data[done+2] * 0x10000 + data[done+3] * 0x1000000)
done += 4
if last != first:
self._logger.warn('deprecated', 'item.last')
item = ItemContent(cid, cksum, first)
if done > size:
raise InvalidDataError(
'Content item overran block end at ' + str(done))
while data[done] in (0xa0, 0xa1):
self._logger.warn('deprecated', 'item.update')
done += 1
checksum = None
if data[done-1] == 0xa1:
checksum = data[done:done+sumlen]
done += sumlen
first = (
data[done] + data[done+1] * 0x100 +
data[done+2] * 0x10000 + data[done+3] * 0x1000000)
done += 4
last = (
data[done] + data[done+1] * 0x100 +
data[done+2] * 0x10000 + data[done+3] * 0x1000000)
done += 4
if done > size:
raise InvalidDataError(
'Content item overran block end at ' + str(done))
block._items.append((data[start:done], item))
block._datasize += done - start
elif data[done] == 0:
if data[done:size].strip(b'\x00'):
raise InvalidDataError('Trailing garbage')
done = size
else:
raise InvalidDataError('Unknown data item: ' + str(data[done]))
return block
def decode_block(self, data, size):
if size > len(data):
size = len(data)
done = 0
block = BackupBlock()
while done < size:
item = None
start = done
if data[done] in (0x90, 0x92):
itemtype = data[done]
done += 1
dirid, done = valuecodecs.parse_varuint(data, done)
parent, done = valuecodecs.parse_varuint(data, done)
namelen, done = valuecodecs.parse_varuint(data, done)
name = data[done:done+namelen]
done += namelen
item = ItemDirectory(dirid, parent, name)
if itemtype == 0x92:
extra_data, done = valuecodecs.parse_varuint(data, done)
item.set_extra_data(extra_data)
itemdata = data[start:done]
elif data[done] in (0x91, 0x93, 0x94):
itemtype = data[done]
done += 1
parent, done = valuecodecs.parse_varuint(data, done)
namelen, done = valuecodecs.parse_varuint(data, done)
name = data[done:done+namelen]
done += namelen
cidlen, done = valuecodecs.parse_varuint(data, done)
cid = data[done:done+cidlen]
done += cidlen
filesize, done = valuecodecs.parse_varuint(data, done)
mtime_year = data[done] + data[done+1] * 256
mtime_second = (
data[done+2] + data[done+3] * 0x100 +
data[done+4] * 0x10000)
if data[done+5] >= 0x80:
mtime_second += 0x1000000
mtime_ns = (
(data[done+5] & 0x3f) + data[done+6] * 0x40 +
data[done+7] * 0x4000 + data[done+8] * 0x400000)
done += 9
if itemtype in (0x91, 0x93):
item = ItemFile(
parent, name, cid, filesize,
(mtime_year, mtime_second, mtime_ns))
elif itemtype == 0x94:
ftype = self._filetypechars.get(data[done])
if ftype is None:
raise AssertionError(
'Unknown filetype: ' + str(data[done]))
done += 1
item = ItemSpecialFile(
ftype, parent, name, cid, filesize,
(mtime_year, mtime_second, mtime_ns))
else:
raise AssertionError('unreachable')
if itemtype in (0x93, 0x94):
extra, done = valuecodecs.parse_varuint(data, done)
item.set_extra_data(extra)
itemdata = data[start:done]
elif data[done] == 0x21:
done += 1
length, done = valuecodecs.parse_varuint(data, done)
end = done + length
kvid, done = valuecodecs.parse_varuint(data, done)
kv = data[done:end]
done = end
key, value = kv.split(b':', 1)
item = ItemKeyValue(kvid, key, value)
itemdata = data[start:done]
elif data[done] == 0x22:
done += 1
length, done = valuecodecs.parse_varuint(data, done)
end = done + length
xid, done = valuecodecs.parse_varuint(data, done)
kvids = []
while done < end:
kvid, done = valuecodecs.parse_varuint(data, done)
kvids.append(kvid)
assert done == end
item = ItemExtraDef(xid, tuple(kvids))
itemdata = data[start:done]
elif data[done] == 0:
if data[done:size].strip(b'\x00'):
raise InvalidDataError('Trailing garbage')
done = size
else:
raise InvalidDataError('Unknown data item')
if item is not None:
block._items.append((itemdata, item))
block._datasize += len(itemdata)
return block