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#
# Copyright (C) 2009-2010 John Garland <johnnybg+deluge@gmail.com>
#
# This file is part of Deluge and is licensed under GNU General Public License 3.0, or later, with
# the additional special exception to link portions of this program with the OpenSSL library.
# See LICENSE for more details.
#
from .decompressers import BZipped2, GZipped, Zipped
from .readers import EmuleReader, PeerGuardianReader, SafePeerReader
COMPRESSION_TYPES = {b'PK': 'Zip', b'\x1f\x8b': 'GZip', b'BZ': 'BZip2'}
DECOMPRESSERS = {'Zip': Zipped, 'GZip': GZipped, 'BZip2': BZipped2}
READERS = {
'Emule': EmuleReader,
'SafePeer': SafePeerReader,
'PeerGuardian': PeerGuardianReader,
}
class UnknownFormatError(Exception):
pass
def detect_compression(filename):
with open(filename, 'rb') as _file:
magic_number = _file.read(2)
return COMPRESSION_TYPES.get(magic_number, '')
def detect_format(filename, compression=''):
file_format = ''
for reader in READERS:
if create_reader(reader, compression)(filename).is_valid():
file_format = reader
break
return file_format
def create_reader(file_format, compression=''):
reader = READERS.get(file_format)
if reader and compression:
decompressor = DECOMPRESSERS.get(compression)
if decompressor:
reader = decompressor(reader)
return reader
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