readmdict.py 文件源码

def _decode_key_block(self, key_block_compressed, key_block_info_list):
        key_list = []
        i = 0
        for compressed_size, decompressed_size in key_block_info_list:
            start = i
            end = i + compressed_size
            # 4 bytes : compression type
            key_block_type = key_block_compressed[start:start + 4]
            # 4 bytes : adler checksum of decompressed key block
            adler32 = unpack('>I', key_block_compressed[start + 4:start + 8])[0]
            if key_block_type == b'\x00\x00\x00\x00':
                key_block = key_block_compressed[start + 8:end]
            elif key_block_type == b'\x01\x00\x00\x00':
                if lzo is None:
                    print("LZO compression is not supported")
                    break
                # decompress key block
                header = b'\xf0' + pack('>I', decompressed_size)
                key_block = lzo.decompress(key_block_compressed[start + 8:end], initSize = decompressed_size, blockSize=1308672)
            elif key_block_type == b'\x02\x00\x00\x00':
                # decompress key block
                key_block = zlib.decompress(key_block_compressed[start + 8:end])
            # extract one single key block into a key list
            key_list += self._split_key_block(key_block)
            # notice that adler32 returns signed value
            assert(adler32 == zlib.adler32(key_block) & 0xffffffff)

            i += compressed_size
        return key_list