zipfile.py 文件源码

def __init__(self, fileobj, mode, zipinfo, decrypter=None):
        self._fileobj = fileobj
        self._decrypter = decrypter

        self._compress_type = zipinfo.compress_type
        self._compress_size = zipinfo.compress_size
        self._compress_left = zipinfo.compress_size

        if self._compress_type == ZIP_DEFLATED:
            self._decompressor = zlib.decompressobj(-15)
        self._unconsumed = ''

        self._readbuffer = ''
        self._offset = 0

        self._universal = 'U' in mode
        self.newlines = None

        # Adjust read size for encrypted files since the first 12 bytes
        # are for the encryption/password information.
        if self._decrypter is not None:
            self._compress_left -= 12

        self.mode = mode
        self.name = zipinfo.filename

        if hasattr(zipinfo, 'CRC'):
            self._expected_crc = zipinfo.CRC
            self._running_crc = crc32(b'') & 0xffffffff
        else:
            self._expected_crc = None