閱讀zlib檔案列表

Question

我有一個文件，其中包含許多zlib檔案本身。該文件的 結構如下：

+-------------------------+ 
|+-----------------------+| 
||  CMF+FLG (78DA) || 
|+-----------------------+| 
|+-----------------------+| 
||...compressed data 1...|| 
|+-----------------------+| 
|+-----------------------+| 
||  ADLER32  || 
|+-----------------------+| 
| 
|+-----------------------+| 
||  CMF+FLG (78DA) || 
|+-----------------------+| 
|+-----------------------+| 
||...compressed data 2...|| 
|+-----------------------+| 
|+-----------------------+| 
||  ADLER32  || 
|+-----------------------+| 
| 
|+-----------------------+| 
||  CMF+FLG (78DA) || 
|+-----------------------+| 
|+-----------------------+| 
||...compressed data 3...|| 
|+-----------------------+| 
|+-----------------------+| 
||  ADLER32  || 
|+-----------------------+| 
|       | 
|.........................| 
|       | 
|+-----------------------+| 
||  CMF+FLG (78DA) || 
|+-----------------------+| 
|+-----------------------+| 
||...compressed data n...|| 
|+-----------------------+| 
|+-----------------------+| 
||  ADLER32  || 
|+-----------------------+| 
+-------------------------+ 

，我需要遍歷所有的歸檔和提取它們。 我試過下面的代碼，但是這隻從文件中提取第一個存檔。

for filename in sys.argv[1:]: 
    with open(filename, 'r') as compressed: 
     with open(filename + '-decompressed', 'w') as expanded: 
      data = zlib.decompress(compressed.read()) 
      expanded.write(data) 

Answer 1

您應該能夠使用這樣的一系列減壓對象：

import zlib 

with open(filename, 'rb') as compressed: 
    data = compressed.read() 
    file_no = 0 

    while data: 
     d = zlib.decompressobj() 
     with open('{}_decompressed.{}'.format(filename, file_no), 'wb') as f: 
      f.write(d.decompress(data)) 
     data = d.unused_data 
     file_no += 1 

這將需要一個單一的文件，其中包含多個鏈接的zlib壓縮文件並解壓縮每一個單獨的文件與「_decompressed.n」附加到原始文件名稱。

關鍵是要使用解壓縮對象的unused_data屬性來確定字符串中是否存在任何未壓縮的數據。