Function crc32

Lib/zipfile/__init__.py:723–725

Compute the CRC32 primitive on one byte.

(ch, crc)

    crctable = _crctable

    def crc32(ch, crc):
        """Compute the CRC32 primitive on one byte."""
        return (crc >> 8) ^ crctable[(crc ^ ch) & 0xFF]

    def update_keys(c):
        nonlocal key0, key1, key2