degourou/decrypt/zeroedzipinfo.py

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2023-02-23 02:09:53 -05:00
#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Python 3's "zipfile" has an annoying bug where the `external_attr` field
of a ZIP file cannot be set to 0. However, if the original DRMed ZIP has
that set to 0 then we want the DRM-free ZIP to have that as 0, too.
See https://github.com/python/cpython/issues/87713
We cannot just set the "external_attr" to 0 as the code to save the ZIP
resets that variable.
So, here's a class that inherits from ZipInfo and ensures that EVERY
read access to that variable will return a 0 ...
"""
import zipfile
class ZeroedZipInfo(zipfile.ZipInfo):
def __init__(self, zinfo):
for k in self.__slots__:
if hasattr(zinfo, k):
setattr(self, k, getattr(zinfo, k))
def __getattribute__(self, name):
if name == "external_attr":
return 0
return object.__getattribute__(self, name)