[issue18515] zipfile._ZipDecryptor generates wasteful crc32 table on import

[Serhiy Storchaka]

Serhiy Storchaka added the comment:

The objection to zipfile-no-crc32.patch is that binascii.crc32() and _crc32() have different signatures. binascii.crc32() accepts a byte object while _crc32() accepts a single integer. With packing this value into a bytes object _crc32() will be much slower.

As for zdlazy.patch, there is a proposed patch in issue10030 which speedups pure Python decryption. I'm afraid that with zdlazy.patch this path will lose a part of it's speedup.

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Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue18515>
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