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Python shutil模块

时间:2017-09-13 18:31:47      阅读:267      评论:0      收藏:0      [点我收藏+]

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高级的 文件、文件夹、压缩包 处理模块

shutil.copyfileobj(fsrc, fdst[, length])
将文件内容拷贝到另一个文件中,可以部分内容

1 def copyfileobj(fsrc, fdst, length=16*1024):
2     """copy data from file-like object fsrc to file-like object fdst"""
3     while 1:
4         buf = fsrc.read(length)
5         if not buf:
6             break
7         fdst.write(buf)

shutil.copyfile(src, dst)
拷贝文件

def copyfile(src, dst):
    """Copy data from src to dst"""
    if _samefile(src, dst):
        raise Error("`%s` and `%s` are the same file" % (src, dst))

    for fn in [src, dst]:
        try:
            st = os.stat(fn)
        except OSError:
            # File most likely does not exist
            pass
        else:
            # XXX What about other special files? (sockets, devices...)
            if stat.S_ISFIFO(st.st_mode):
                raise SpecialFileError("`%s` is a named pipe" % fn)

    with open(src, rb) as fsrc:
        with open(dst, wb) as fdst:
            copyfileobj(fsrc, fdst)

shutil.copymode(src, dst)
仅拷贝权限。内容、组、用户均不变

1 def copymode(src, dst):
2     """Copy mode bits from src to dst"""
3     if hasattr(os, chmod):
4         st = os.stat(src)
5         mode = stat.S_IMODE(st.st_mode)
6         os.chmod(dst, mode)

shutil.copystat(src, dst)
拷贝状态的信息,包括:mode bits, atime, mtime, flags

 1 def copystat(src, dst):
 2     """Copy all stat info (mode bits, atime, mtime, flags) from src to dst"""
 3     st = os.stat(src)
 4     mode = stat.S_IMODE(st.st_mode)
 5     if hasattr(os, utime):
 6         os.utime(dst, (st.st_atime, st.st_mtime))
 7     if hasattr(os, chmod):
 8         os.chmod(dst, mode)
 9     if hasattr(os, chflags) and hasattr(st, st_flags):
10         try:
11             os.chflags(dst, st.st_flags)
12         except OSError, why:
13             for err in EOPNOTSUPP, ENOTSUP:
14                 if hasattr(errno, err) and why.errno == getattr(errno, err):
15                     break
16             else:
17                 raise

shutil.copy(src, dst)
拷贝文件和权限

 1 def copy(src, dst):
 2     """Copy data and mode bits ("cp src dst").
 3 
 4     The destination may be a directory.
 5 
 6     """
 7     if os.path.isdir(dst):
 8         dst = os.path.join(dst, os.path.basename(src))
 9     copyfile(src, dst)
10     copymode(src, dst)

shutil.copy2(src, dst)
拷贝文件和状态信息

 1 def copy2(src, dst):
 2     """Copy data and all stat info ("cp -p src dst").
 3 
 4     The destination may be a directory.
 5 
 6     """
 7     if os.path.isdir(dst):
 8         dst = os.path.join(dst, os.path.basename(src))
 9     copyfile(src, dst)
10     copystat(src, dst)

shutil.ignore_patterns(*patterns)
shutil.copytree(src, dst, symlinks=False, ignore=None)
递归的去拷贝文件

例如:copytree(source, destination, ignore=ignore_patterns(‘*.pyc‘, ‘tmp*‘))

 1 def ignore_patterns(*patterns):
 2     """Function that can be used as copytree() ignore parameter.
 3 
 4     Patterns is a sequence of glob-style patterns
 5     that are used to exclude files"""
 6     def _ignore_patterns(path, names):
 7         ignored_names = []
 8         for pattern in patterns:
 9             ignored_names.extend(fnmatch.filter(names, pattern))
10         return set(ignored_names)
11     return _ignore_patterns
12 
13 def copytree(src, dst, symlinks=False, ignore=None):
14     """Recursively copy a directory tree using copy2().
15 
16     The destination directory must not already exist.
17     If exception(s) occur, an Error is raised with a list of reasons.
18 
19     If the optional symlinks flag is true, symbolic links in the
20     source tree result in symbolic links in the destination tree; if
21     it is false, the contents of the files pointed to by symbolic
22     links are copied.
23 
24     The optional ignore argument is a callable. If given, it
25     is called with the `src` parameter, which is the directory
26     being visited by copytree(), and `names` which is the list of
27     `src` contents, as returned by os.listdir():
28 
29         callable(src, names) -> ignored_names
30 
31     Since copytree() is called recursively, the callable will be
32     called once for each directory that is copied. It returns a
33     list of names relative to the `src` directory that should
34     not be copied.
35 
36     XXX Consider this example code rather than the ultimate tool.
37 
38     """
39     names = os.listdir(src)
40     if ignore is not None:
41         ignored_names = ignore(src, names)
42     else:
43         ignored_names = set()
44 
45     os.makedirs(dst)
46     errors = []
47     for name in names:
48         if name in ignored_names:
49             continue
50         srcname = os.path.join(src, name)
51         dstname = os.path.join(dst, name)
52         try:
53             if symlinks and os.path.islink(srcname):
54                 linkto = os.readlink(srcname)
55                 os.symlink(linkto, dstname)
56             elif os.path.isdir(srcname):
57                 copytree(srcname, dstname, symlinks, ignore)
58             else:
59                 # Will raise a SpecialFileError for unsupported file types
60                 copy2(srcname, dstname)
61         # catch the Error from the recursive copytree so that we can
62         # continue with other files
63         except Error, err:
64             errors.extend(err.args[0])
65         except EnvironmentError, why:
66             errors.append((srcname, dstname, str(why)))
67     try:
68         copystat(src, dst)
69     except OSError, why:
70         if WindowsError is not None and isinstance(why, WindowsError):
71             # Copying file access times may fail on Windows
72             pass
73         else:
74             errors.append((src, dst, str(why)))
75     if errors:
76         raise Error, errors

shutil.rmtree(path[, ignore_errors[, onerror]])
递归的去删除文件

技术分享
 1 def rmtree(path, ignore_errors=False, onerror=None):
 2     """Recursively delete a directory tree.
 3 
 4     If ignore_errors is set, errors are ignored; otherwise, if onerror
 5     is set, it is called to handle the error with arguments (func,
 6     path, exc_info) where func is os.listdir, os.remove, or os.rmdir;
 7     path is the argument to that function that caused it to fail; and
 8     exc_info is a tuple returned by sys.exc_info().  If ignore_errors
 9     is false and onerror is None, an exception is raised.
10 
11     """
12     if ignore_errors:
13         def onerror(*args):
14             pass
15     elif onerror is None:
16         def onerror(*args):
17             raise
18     try:
19         if os.path.islink(path):
20             # symlinks to directories are forbidden, see bug #1669
21             raise OSError("Cannot call rmtree on a symbolic link")
22     except OSError:
23         onerror(os.path.islink, path, sys.exc_info())
24         # can‘t continue even if onerror hook returns
25         return
26     names = []
27     try:
28         names = os.listdir(path)
29     except os.error, err:
30         onerror(os.listdir, path, sys.exc_info())
31     for name in names:
32         fullname = os.path.join(path, name)
33         try:
34             mode = os.lstat(fullname).st_mode
35         except os.error:
36             mode = 0
37         if stat.S_ISDIR(mode):
38             rmtree(fullname, ignore_errors, onerror)
39         else:
40             try:
41                 os.remove(fullname)
42             except os.error, err:
43                 onerror(os.remove, fullname, sys.exc_info())
44     try:
45         os.rmdir(path)
46     except os.error:
47         onerror(os.rmdir, path, sys.exc_info())
View Code

shutil.move(src, dst)
递归的去移动文件

技术分享
 1 def move(src, dst):
 2     """Recursively move a file or directory to another location. This is
 3     similar to the Unix "mv" command.
 4 
 5     If the destination is a directory or a symlink to a directory, the source
 6     is moved inside the directory. The destination path must not already
 7     exist.
 8 
 9     If the destination already exists but is not a directory, it may be
10     overwritten depending on os.rename() semantics.
11 
12     If the destination is on our current filesystem, then rename() is used.
13     Otherwise, src is copied to the destination and then removed.
14     A lot more could be done here...  A look at a mv.c shows a lot of
15     the issues this implementation glosses over.
16 
17     """
18     real_dst = dst
19     if os.path.isdir(dst):
20         if _samefile(src, dst):
21             # We might be on a case insensitive filesystem,
22             # perform the rename anyway.
23             os.rename(src, dst)
24             return
25 
26         real_dst = os.path.join(dst, _basename(src))
27         if os.path.exists(real_dst):
28             raise Error, "Destination path ‘%s‘ already exists" % real_dst
29     try:
30         os.rename(src, real_dst)
31     except OSError:
32         if os.path.isdir(src):
33             if _destinsrc(src, dst):
34                 raise Error, "Cannot move a directory ‘%s‘ into itself ‘%s‘." % (src, dst)
35             copytree(src, real_dst, symlinks=True)
36             rmtree(src)
37         else:
38             copy2(src, real_dst)
39             os.unlink(src)
View Code

shutil.make_archive(base_name, format,...)

创建压缩包并返回文件路径,例如:zip、tar

  • base_name: 压缩包的文件名,也可以是压缩包的路径。只是文件名时,则保存至当前目录,否则保存至指定路径,

            如:www                        =>保存至当前路径

           如:/Users/wupeiqi/www =>保存至/Users/wupeiqi/

  • format: 压缩包种类,“zip”, “tar”, “bztar”,“gztar”
  • root_dir: 要压缩的文件夹路径(默认当前目录)
  • owner: 用户,默认当前用户
  • group: 组,默认当前组
  • logger: 用于记录日志,通常是logging.Logger对象
    1 #将 /Users/wupeiqi/Downloads/test 下的文件打包放置当前程序目录
    2  
    3 import shutil
    4 ret = shutil.make_archive("wwwwwwwwww", gztar, root_dir=/Users/wupeiqi/Downloads/test)
    5  
    6  
    7 #将 /Users/wupeiqi/Downloads/test 下的文件打包放置 /Users/wupeiqi/目录
    8 import shutil
    9 ret = shutil.make_archive("/Users/wupeiqi/wwwwwwwwww", gztar, root_dir=/Users/wupeiqi/Downloads/test)
    技术分享
     1 def make_archive(base_name, format, root_dir=None, base_dir=None, verbose=0,
     2                  dry_run=0, owner=None, group=None, logger=None):
     3     """Create an archive file (eg. zip or tar).
     4 
     5     ‘base_name‘ is the name of the file to create, minus any format-specific
     6     extension; ‘format‘ is the archive format: one of "zip", "tar", "bztar"
     7     or "gztar".
     8 
     9     ‘root_dir‘ is a directory that will be the root directory of the
    10     archive; ie. we typically chdir into ‘root_dir‘ before creating the
    11     archive.  ‘base_dir‘ is the directory where we start archiving from;
    12     ie. ‘base_dir‘ will be the common prefix of all files and
    13     directories in the archive.  ‘root_dir‘ and ‘base_dir‘ both default
    14     to the current directory.  Returns the name of the archive file.
    15 
    16     ‘owner‘ and ‘group‘ are used when creating a tar archive. By default,
    17     uses the current owner and group.
    18     """
    19     save_cwd = os.getcwd()
    20     if root_dir is not None:
    21         if logger is not None:
    22             logger.debug("changing into ‘%s‘", root_dir)
    23         base_name = os.path.abspath(base_name)
    24         if not dry_run:
    25             os.chdir(root_dir)
    26 
    27     if base_dir is None:
    28         base_dir = os.curdir
    29 
    30     kwargs = {dry_run: dry_run, logger: logger}
    31 
    32     try:
    33         format_info = _ARCHIVE_FORMATS[format]
    34     except KeyError:
    35         raise ValueError, "unknown archive format ‘%s‘" % format
    36 
    37     func = format_info[0]
    38     for arg, val in format_info[1]:
    39         kwargs[arg] = val
    40 
    41     if format != zip:
    42         kwargs[owner] = owner
    43         kwargs[group] = group
    44 
    45     try:
    46         filename = func(base_name, base_dir, **kwargs)
    47     finally:
    48         if root_dir is not None:
    49             if logger is not None:
    50                 logger.debug("changing back to ‘%s‘", save_cwd)
    51             os.chdir(save_cwd)
    52 
    53     return filename
    View Code

    shutil 对压缩包的处理是调用 ZipFile 和 TarFile 两个模块来进行的,详细:

    技术分享
     1 import zipfile
     2 
     3 # 压缩
     4 z = zipfile.ZipFile(laxi.zip, w)
     5 z.write(a.log)
     6 z.write(data.data)
     7 z.close()
     8 
     9 # 解压
    10 z = zipfile.ZipFile(laxi.zip, r)
    11 z.extractall()
    12 z.close()
    13 
    14 zipfile 压缩解压
    zipfilr 压缩解压
    技术分享
     1 import tarfile
     2 
     3 # 压缩
     4 tar = tarfile.open(your.tar,w)
     5 tar.add(/Users/wupeiqi/PycharmProjects/bbs2.zip, arcname=bbs2.zip)
     6 tar.add(/Users/wupeiqi/PycharmProjects/cmdb.zip, arcname=cmdb.zip)
     7 tar.close()
     8 
     9 # 解压
    10 tar = tarfile.open(your.tar,r)
    11 tar.extractall()  # 可设置解压地址
    12 tar.close()
    13 
    14 tarfile 压缩解压
    tarfile 压缩解压
    技术分享
      1 class ZipFile(object):
      2     """ Class with methods to open, read, write, close, list zip files.
      3 
      4     z = ZipFile(file, mode="r", compression=ZIP_STORED, allowZip64=False)
      5 
      6     file: Either the path to the file, or a file-like object.
      7           If it is a path, the file will be opened and closed by ZipFile.
      8     mode: The mode can be either read "r", write "w" or append "a".
      9     compression: ZIP_STORED (no compression) or ZIP_DEFLATED (requires zlib).
     10     allowZip64: if True ZipFile will create files with ZIP64 extensions when
     11                 needed, otherwise it will raise an exception when this would
     12                 be necessary.
     13 
     14     """
     15 
     16     fp = None                   # Set here since __del__ checks it
     17 
     18     def __init__(self, file, mode="r", compression=ZIP_STORED, allowZip64=False):
     19         """Open the ZIP file with mode read "r", write "w" or append "a"."""
     20         if mode not in ("r", "w", "a"):
     21             raise RuntimeError(ZipFile() requires mode "r", "w", or "a")
     22 
     23         if compression == ZIP_STORED:
     24             pass
     25         elif compression == ZIP_DEFLATED:
     26             if not zlib:
     27                 raise RuntimeError, 28                       "Compression requires the (missing) zlib module"
     29         else:
     30             raise RuntimeError, "That compression method is not supported"
     31 
     32         self._allowZip64 = allowZip64
     33         self._didModify = False
     34         self.debug = 0  # Level of printing: 0 through 3
     35         self.NameToInfo = {}    # Find file info given name
     36         self.filelist = []      # List of ZipInfo instances for archive
     37         self.compression = compression  # Method of compression
     38         self.mode = key = mode.replace(b, ‘‘)[0]
     39         self.pwd = None
     40         self._comment = ‘‘
     41 
     42         # Check if we were passed a file-like object
     43         if isinstance(file, basestring):
     44             self._filePassed = 0
     45             self.filename = file
     46             modeDict = {r : rb, w: wb, a : r+b}
     47             try:
     48                 self.fp = open(file, modeDict[mode])
     49             except IOError:
     50                 if mode == a:
     51                     mode = key = w
     52                     self.fp = open(file, modeDict[mode])
     53                 else:
     54                     raise
     55         else:
     56             self._filePassed = 1
     57             self.fp = file
     58             self.filename = getattr(file, name, None)
     59 
     60         try:
     61             if key == r:
     62                 self._RealGetContents()
     63             elif key == w:
     64                 # set the modified flag so central directory gets written
     65                 # even if no files are added to the archive
     66                 self._didModify = True
     67             elif key == a:
     68                 try:
     69                     # See if file is a zip file
     70                     self._RealGetContents()
     71                     # seek to start of directory and overwrite
     72                     self.fp.seek(self.start_dir, 0)
     73                 except BadZipfile:
     74                     # file is not a zip file, just append
     75                     self.fp.seek(0, 2)
     76 
     77                     # set the modified flag so central directory gets written
     78                     # even if no files are added to the archive
     79                     self._didModify = True
     80             else:
     81                 raise RuntimeError(Mode must be "r", "w" or "a")
     82         except:
     83             fp = self.fp
     84             self.fp = None
     85             if not self._filePassed:
     86                 fp.close()
     87             raise
     88 
     89     def __enter__(self):
     90         return self
     91 
     92     def __exit__(self, type, value, traceback):
     93         self.close()
     94 
     95     def _RealGetContents(self):
     96         """Read in the table of contents for the ZIP file."""
     97         fp = self.fp
     98         try:
     99             endrec = _EndRecData(fp)
    100         except IOError:
    101             raise BadZipfile("File is not a zip file")
    102         if not endrec:
    103             raise BadZipfile, "File is not a zip file"
    104         if self.debug > 1:
    105             print endrec
    106         size_cd = endrec[_ECD_SIZE]             # bytes in central directory
    107         offset_cd = endrec[_ECD_OFFSET]         # offset of central directory
    108         self._comment = endrec[_ECD_COMMENT]    # archive comment
    109 
    110         # "concat" is zero, unless zip was concatenated to another file
    111         concat = endrec[_ECD_LOCATION] - size_cd - offset_cd
    112         if endrec[_ECD_SIGNATURE] == stringEndArchive64:
    113             # If Zip64 extension structures are present, account for them
    114             concat -= (sizeEndCentDir64 + sizeEndCentDir64Locator)
    115 
    116         if self.debug > 2:
    117             inferred = concat + offset_cd
    118             print "given, inferred, offset", offset_cd, inferred, concat
    119         # self.start_dir:  Position of start of central directory
    120         self.start_dir = offset_cd + concat
    121         fp.seek(self.start_dir, 0)
    122         data = fp.read(size_cd)
    123         fp = cStringIO.StringIO(data)
    124         total = 0
    125         while total < size_cd:
    126             centdir = fp.read(sizeCentralDir)
    127             if len(centdir) != sizeCentralDir:
    128                 raise BadZipfile("Truncated central directory")
    129             centdir = struct.unpack(structCentralDir, centdir)
    130             if centdir[_CD_SIGNATURE] != stringCentralDir:
    131                 raise BadZipfile("Bad magic number for central directory")
    132             if self.debug > 2:
    133                 print centdir
    134             filename = fp.read(centdir[_CD_FILENAME_LENGTH])
    135             # Create ZipInfo instance to store file information
    136             x = ZipInfo(filename)
    137             x.extra = fp.read(centdir[_CD_EXTRA_FIELD_LENGTH])
    138             x.comment = fp.read(centdir[_CD_COMMENT_LENGTH])
    139             x.header_offset = centdir[_CD_LOCAL_HEADER_OFFSET]
    140             (x.create_version, x.create_system, x.extract_version, x.reserved,
    141                 x.flag_bits, x.compress_type, t, d,
    142                 x.CRC, x.compress_size, x.file_size) = centdir[1:12]
    143             x.volume, x.internal_attr, x.external_attr = centdir[15:18]
    144             # Convert date/time code to (year, month, day, hour, min, sec)
    145             x._raw_time = t
    146             x.date_time = ( (d>>9)+1980, (d>>5)&0xF, d&0x1F,
    147                                      t>>11, (t>>5)&0x3F, (t&0x1F) * 2 )
    148 
    149             x._decodeExtra()
    150             x.header_offset = x.header_offset + concat
    151             x.filename = x._decodeFilename()
    152             self.filelist.append(x)
    153             self.NameToInfo[x.filename] = x
    154 
    155             # update total bytes read from central directory
    156             total = (total + sizeCentralDir + centdir[_CD_FILENAME_LENGTH]
    157                      + centdir[_CD_EXTRA_FIELD_LENGTH]
    158                      + centdir[_CD_COMMENT_LENGTH])
    159 
    160             if self.debug > 2:
    161                 print "total", total
    162 
    163 
    164     def namelist(self):
    165         """Return a list of file names in the archive."""
    166         l = []
    167         for data in self.filelist:
    168             l.append(data.filename)
    169         return l
    170 
    171     def infolist(self):
    172         """Return a list of class ZipInfo instances for files in the
    173         archive."""
    174         return self.filelist
    175 
    176     def printdir(self):
    177         """Print a table of contents for the zip file."""
    178         print "%-46s %19s %12s" % ("File Name", "Modified    ", "Size")
    179         for zinfo in self.filelist:
    180             date = "%d-%02d-%02d %02d:%02d:%02d" % zinfo.date_time[:6]
    181             print "%-46s %s %12d" % (zinfo.filename, date, zinfo.file_size)
    182 
    183     def testzip(self):
    184         """Read all the files and check the CRC."""
    185         chunk_size = 2 ** 20
    186         for zinfo in self.filelist:
    187             try:
    188                 # Read by chunks, to avoid an OverflowError or a
    189                 # MemoryError with very large embedded files.
    190                 with self.open(zinfo.filename, "r") as f:
    191                     while f.read(chunk_size):     # Check CRC-32
    192                         pass
    193             except BadZipfile:
    194                 return zinfo.filename
    195 
    196     def getinfo(self, name):
    197         """Return the instance of ZipInfo given ‘name‘."""
    198         info = self.NameToInfo.get(name)
    199         if info is None:
    200             raise KeyError(
    201                 There is no item named %r in the archive % name)
    202 
    203         return info
    204 
    205     def setpassword(self, pwd):
    206         """Set default password for encrypted files."""
    207         self.pwd = pwd
    208 
    209     @property
    210     def comment(self):
    211         """The comment text associated with the ZIP file."""
    212         return self._comment
    213 
    214     @comment.setter
    215     def comment(self, comment):
    216         # check for valid comment length
    217         if len(comment) > ZIP_MAX_COMMENT:
    218             import warnings
    219             warnings.warn(Archive comment is too long; truncating to %d bytes
    220                           % ZIP_MAX_COMMENT, stacklevel=2)
    221             comment = comment[:ZIP_MAX_COMMENT]
    222         self._comment = comment
    223         self._didModify = True
    224 
    225     def read(self, name, pwd=None):
    226         """Return file bytes (as a string) for name."""
    227         return self.open(name, "r", pwd).read()
    228 
    229     def open(self, name, mode="r", pwd=None):
    230         """Return file-like object for ‘name‘."""
    231         if mode not in ("r", "U", "rU"):
    232             raise RuntimeError, open() requires mode "r", "U", or "rU"
    233         if not self.fp:
    234             raise RuntimeError, 235                   "Attempt to read ZIP archive that was already closed"
    236 
    237         # Only open a new file for instances where we were not
    238         # given a file object in the constructor
    239         if self._filePassed:
    240             zef_file = self.fp
    241             should_close = False
    242         else:
    243             zef_file = open(self.filename, rb)
    244             should_close = True
    245 
    246         try:
    247             # Make sure we have an info object
    248             if isinstance(name, ZipInfo):
    249                 # ‘name‘ is already an info object
    250                 zinfo = name
    251             else:
    252                 # Get info object for name
    253                 zinfo = self.getinfo(name)
    254 
    255             zef_file.seek(zinfo.header_offset, 0)
    256 
    257             # Skip the file header:
    258             fheader = zef_file.read(sizeFileHeader)
    259             if len(fheader) != sizeFileHeader:
    260                 raise BadZipfile("Truncated file header")
    261             fheader = struct.unpack(structFileHeader, fheader)
    262             if fheader[_FH_SIGNATURE] != stringFileHeader:
    263                 raise BadZipfile("Bad magic number for file header")
    264 
    265             fname = zef_file.read(fheader[_FH_FILENAME_LENGTH])
    266             if fheader[_FH_EXTRA_FIELD_LENGTH]:
    267                 zef_file.read(fheader[_FH_EXTRA_FIELD_LENGTH])
    268 
    269             if fname != zinfo.orig_filename:
    270                 raise BadZipfile, 271                         File name in directory "%s" and header "%s" differ. % (
    272                             zinfo.orig_filename, fname)
    273 
    274             # check for encrypted flag & handle password
    275             is_encrypted = zinfo.flag_bits & 0x1
    276             zd = None
    277             if is_encrypted:
    278                 if not pwd:
    279                     pwd = self.pwd
    280                 if not pwd:
    281                     raise RuntimeError, "File %s is encrypted, " 282                         "password required for extraction" % name
    283 
    284                 zd = _ZipDecrypter(pwd)
    285                 # The first 12 bytes in the cypher stream is an encryption header
    286                 #  used to strengthen the algorithm. The first 11 bytes are
    287                 #  completely random, while the 12th contains the MSB of the CRC,
    288                 #  or the MSB of the file time depending on the header type
    289                 #  and is used to check the correctness of the password.
    290                 bytes = zef_file.read(12)
    291                 h = map(zd, bytes[0:12])
    292                 if zinfo.flag_bits & 0x8:
    293                     # compare against the file type from extended local headers
    294                     check_byte = (zinfo._raw_time >> 8) & 0xff
    295                 else:
    296                     # compare against the CRC otherwise
    297                     check_byte = (zinfo.CRC >> 24) & 0xff
    298                 if ord(h[11]) != check_byte:
    299                     raise RuntimeError("Bad password for file", name)
    300 
    301             return ZipExtFile(zef_file, mode, zinfo, zd,
    302                     close_fileobj=should_close)
    303         except:
    304             if should_close:
    305                 zef_file.close()
    306             raise
    307 
    308     def extract(self, member, path=None, pwd=None):
    309         """Extract a member from the archive to the current working directory,
    310            using its full name. Its file information is extracted as accurately
    311            as possible. `member‘ may be a filename or a ZipInfo object. You can
    312            specify a different directory using `path‘.
    313         """
    314         if not isinstance(member, ZipInfo):
    315             member = self.getinfo(member)
    316 
    317         if path is None:
    318             path = os.getcwd()
    319 
    320         return self._extract_member(member, path, pwd)
    321 
    322     def extractall(self, path=None, members=None, pwd=None):
    323         """Extract all members from the archive to the current working
    324            directory. `path‘ specifies a different directory to extract to.
    325            `members‘ is optional and must be a subset of the list returned
    326            by namelist().
    327         """
    328         if members is None:
    329             members = self.namelist()
    330 
    331         for zipinfo in members:
    332             self.extract(zipinfo, path, pwd)
    333 
    334     def _extract_member(self, member, targetpath, pwd):
    335         """Extract the ZipInfo object ‘member‘ to a physical
    336            file on the path targetpath.
    337         """
    338         # build the destination pathname, replacing
    339         # forward slashes to platform specific separators.
    340         arcname = member.filename.replace(/, os.path.sep)
    341 
    342         if os.path.altsep:
    343             arcname = arcname.replace(os.path.altsep, os.path.sep)
    344         # interpret absolute pathname as relative, remove drive letter or
    345         # UNC path, redundant separators, "." and ".." components.
    346         arcname = os.path.splitdrive(arcname)[1]
    347         arcname = os.path.sep.join(x for x in arcname.split(os.path.sep)
    348                     if x not in (‘‘, os.path.curdir, os.path.pardir))
    349         if os.path.sep == \\:
    350             # filter illegal characters on Windows
    351             illegal = :<>|"?*
    352             if isinstance(arcname, unicode):
    353                 table = {ord(c): ord(_) for c in illegal}
    354             else:
    355                 table = string.maketrans(illegal, _ * len(illegal))
    356             arcname = arcname.translate(table)
    357             # remove trailing dots
    358             arcname = (x.rstrip(.) for x in arcname.split(os.path.sep))
    359             arcname = os.path.sep.join(x for x in arcname if x)
    360 
    361         targetpath = os.path.join(targetpath, arcname)
    362         targetpath = os.path.normpath(targetpath)
    363 
    364         # Create all upper directories if necessary.
    365         upperdirs = os.path.dirname(targetpath)
    366         if upperdirs and not os.path.exists(upperdirs):
    367             os.makedirs(upperdirs)
    368 
    369         if member.filename[-1] == /:
    370             if not os.path.isdir(targetpath):
    371                 os.mkdir(targetpath)
    372             return targetpath
    373 
    374         with self.open(member, pwd=pwd) as source, 375              file(targetpath, "wb") as target:
    376             shutil.copyfileobj(source, target)
    377 
    378         return targetpath
    379 
    380     def _writecheck(self, zinfo):
    381         """Check for errors before writing a file to the archive."""
    382         if zinfo.filename in self.NameToInfo:
    383             import warnings
    384             warnings.warn(Duplicate name: %r % zinfo.filename, stacklevel=3)
    385         if self.mode not in ("w", "a"):
    386             raise RuntimeError, write() requires mode "w" or "a"
    387         if not self.fp:
    388             raise RuntimeError, 389                   "Attempt to write ZIP archive that was already closed"
    390         if zinfo.compress_type == ZIP_DEFLATED and not zlib:
    391             raise RuntimeError, 392                   "Compression requires the (missing) zlib module"
    393         if zinfo.compress_type not in (ZIP_STORED, ZIP_DEFLATED):
    394             raise RuntimeError, 395                   "That compression method is not supported"
    396         if not self._allowZip64:
    397             requires_zip64 = None
    398             if len(self.filelist) >= ZIP_FILECOUNT_LIMIT:
    399                 requires_zip64 = "Files count"
    400             elif zinfo.file_size > ZIP64_LIMIT:
    401                 requires_zip64 = "Filesize"
    402             elif zinfo.header_offset > ZIP64_LIMIT:
    403                 requires_zip64 = "Zipfile size"
    404             if requires_zip64:
    405                 raise LargeZipFile(requires_zip64 +
    406                                    " would require ZIP64 extensions")
    407 
    408     def write(self, filename, arcname=None, compress_type=None):
    409         """Put the bytes from filename into the archive under the name
    410         arcname."""
    411         if not self.fp:
    412             raise RuntimeError(
    413                   "Attempt to write to ZIP archive that was already closed")
    414 
    415         st = os.stat(filename)
    416         isdir = stat.S_ISDIR(st.st_mode)
    417         mtime = time.localtime(st.st_mtime)
    418         date_time = mtime[0:6]
    419         # Create ZipInfo instance to store file information
    420         if arcname is None:
    421             arcname = filename
    422         arcname = os.path.normpath(os.path.splitdrive(arcname)[1])
    423         while arcname[0] in (os.sep, os.altsep):
    424             arcname = arcname[1:]
    425         if isdir:
    426             arcname += /
    427         zinfo = ZipInfo(arcname, date_time)
    428         zinfo.external_attr = (st[0] & 0xFFFF) << 16L      # Unix attributes
    429         if compress_type is None:
    430             zinfo.compress_type = self.compression
    431         else:
    432             zinfo.compress_type = compress_type
    433 
    434         zinfo.file_size = st.st_size
    435         zinfo.flag_bits = 0x00
    436         zinfo.header_offset = self.fp.tell()    # Start of header bytes
    437 
    438         self._writecheck(zinfo)
    439         self._didModify = True
    440 
    441         if isdir:
    442             zinfo.file_size = 0
    443             zinfo.compress_size = 0
    444             zinfo.CRC = 0
    445             zinfo.external_attr |= 0x10  # MS-DOS directory flag
    446             self.filelist.append(zinfo)
    447             self.NameToInfo[zinfo.filename] = zinfo
    448             self.fp.write(zinfo.FileHeader(False))
    449             return
    450 
    451         with open(filename, "rb") as fp:
    452             # Must overwrite CRC and sizes with correct data later
    453             zinfo.CRC = CRC = 0
    454             zinfo.compress_size = compress_size = 0
    455             # Compressed size can be larger than uncompressed size
    456             zip64 = self._allowZip64 and 457                     zinfo.file_size * 1.05 > ZIP64_LIMIT
    458             self.fp.write(zinfo.FileHeader(zip64))
    459             if zinfo.compress_type == ZIP_DEFLATED:
    460                 cmpr = zlib.compressobj(zlib.Z_DEFAULT_COMPRESSION,
    461                      zlib.DEFLATED, -15)
    462             else:
    463                 cmpr = None
    464             file_size = 0
    465             while 1:
    466                 buf = fp.read(1024 * 8)
    467                 if not buf:
    468                     break
    469                 file_size = file_size + len(buf)
    470                 CRC = crc32(buf, CRC) & 0xffffffff
    471                 if cmpr:
    472                     buf = cmpr.compress(buf)
    473                     compress_size = compress_size + len(buf)
    474                 self.fp.write(buf)
    475         if cmpr:
    476             buf = cmpr.flush()
    477             compress_size = compress_size + len(buf)
    478             self.fp.write(buf)
    479             zinfo.compress_size = compress_size
    480         else:
    481             zinfo.compress_size = file_size
    482         zinfo.CRC = CRC
    483         zinfo.file_size = file_size
    484         if not zip64 and self._allowZip64:
    485             if file_size > ZIP64_LIMIT:
    486                 raise RuntimeError(File size has increased during compressing)
    487             if compress_size > ZIP64_LIMIT:
    488                 raise RuntimeError(Compressed size larger than uncompressed size)
    489         # Seek backwards and write file header (which will now include
    490         # correct CRC and file sizes)
    491         position = self.fp.tell()       # Preserve current position in file
    492         self.fp.seek(zinfo.header_offset, 0)
    493         self.fp.write(zinfo.FileHeader(zip64))
    494         self.fp.seek(position, 0)
    495         self.filelist.append(zinfo)
    496         self.NameToInfo[zinfo.filename] = zinfo
    497 
    498     def writestr(self, zinfo_or_arcname, bytes, compress_type=None):
    499         """Write a file into the archive.  The contents is the string
    500         ‘bytes‘.  ‘zinfo_or_arcname‘ is either a ZipInfo instance or
    501         the name of the file in the archive."""
    502         if not isinstance(zinfo_or_arcname, ZipInfo):
    503             zinfo = ZipInfo(filename=zinfo_or_arcname,
    504                             date_time=time.localtime(time.time())[:6])
    505 
    506             zinfo.compress_type = self.compression
    507             if zinfo.filename[-1] == /:
    508                 zinfo.external_attr = 0o40775 << 16   # drwxrwxr-x
    509                 zinfo.external_attr |= 0x10           # MS-DOS directory flag
    510             else:
    511                 zinfo.external_attr = 0o600 << 16     # ?rw-------
    512         else:
    513             zinfo = zinfo_or_arcname
    514 
    515         if not self.fp:
    516             raise RuntimeError(
    517                   "Attempt to write to ZIP archive that was already closed")
    518 
    519         if compress_type is not None:
    520             zinfo.compress_type = compress_type
    521 
    522         zinfo.file_size = len(bytes)            # Uncompressed size
    523         zinfo.header_offset = self.fp.tell()    # Start of header bytes
    524         self._writecheck(zinfo)
    525         self._didModify = True
    526         zinfo.CRC = crc32(bytes) & 0xffffffff       # CRC-32 checksum
    527         if zinfo.compress_type == ZIP_DEFLATED:
    528             co = zlib.compressobj(zlib.Z_DEFAULT_COMPRESSION,
    529                  zlib.DEFLATED, -15)
    530             bytes = co.compress(bytes) + co.flush()
    531             zinfo.compress_size = len(bytes)    # Compressed size
    532         else:
    533             zinfo.compress_size = zinfo.file_size
    534         zip64 = zinfo.file_size > ZIP64_LIMIT or 535                 zinfo.compress_size > ZIP64_LIMIT
    536         if zip64 and not self._allowZip64:
    537             raise LargeZipFile("Filesize would require ZIP64 extensions")
    538         self.fp.write(zinfo.FileHeader(zip64))
    539         self.fp.write(bytes)
    540         if zinfo.flag_bits & 0x08:
    541             # Write CRC and file sizes after the file data
    542             fmt = <LQQ if zip64 else <LLL
    543             self.fp.write(struct.pack(fmt, zinfo.CRC, zinfo.compress_size,
    544                   zinfo.file_size))
    545         self.fp.flush()
    546         self.filelist.append(zinfo)
    547         self.NameToInfo[zinfo.filename] = zinfo
    548 
    549     def __del__(self):
    550         """Call the "close()" method in case the user forgot."""
    551         self.close()
    552 
    553     def close(self):
    554         """Close the file, and for mode "w" and "a" write the ending
    555         records."""
    556         if self.fp is None:
    557             return
    558 
    559         try:
    560             if self.mode in ("w", "a") and self._didModify: # write ending records
    561                 pos1 = self.fp.tell()
    562                 for zinfo in self.filelist:         # write central directory
    563                     dt = zinfo.date_time
    564                     dosdate = (dt[0] - 1980) << 9 | dt[1] << 5 | dt[2]
    565                     dostime = dt[3] << 11 | dt[4] << 5 | (dt[5] // 2)
    566                     extra = []
    567                     if zinfo.file_size > ZIP64_LIMIT 568                             or zinfo.compress_size > ZIP64_LIMIT:
    569                         extra.append(zinfo.file_size)
    570                         extra.append(zinfo.compress_size)
    571                         file_size = 0xffffffff
    572                         compress_size = 0xffffffff
    573                     else:
    574                         file_size = zinfo.file_size
    575                         compress_size = zinfo.compress_size
    576 
    577                     if zinfo.header_offset > ZIP64_LIMIT:
    578                         extra.append(zinfo.header_offset)
    579                         header_offset = 0xffffffffL
    580                     else:
    581                         header_offset = zinfo.header_offset
    582 
    583                     extra_data = zinfo.extra
    584                     if extra:
    585                         # Append a ZIP64 field to the extra‘s
    586                         extra_data = struct.pack(
    587                                 <HH + Q*len(extra),
    588                                 1, 8*len(extra), *extra) + extra_data
    589 
    590                         extract_version = max(45, zinfo.extract_version)
    591                         create_version = max(45, zinfo.create_version)
    592                     else:
    593                         extract_version = zinfo.extract_version
    594                         create_version = zinfo.create_version
    595 
    596                     try:
    597                         filename, flag_bits = zinfo._encodeFilenameFlags()
    598                         centdir = struct.pack(structCentralDir,
    599                         stringCentralDir, create_version,
    600                         zinfo.create_system, extract_version, zinfo.reserved,
    601                         flag_bits, zinfo.compress_type, dostime, dosdate,
    602                         zinfo.CRC, compress_size, file_size,
    603                         len(filename), len(extra_data), len(zinfo.comment),
    604                         0, zinfo.internal_attr, zinfo.external_attr,
    605                         header_offset)
    606                     except DeprecationWarning:
    607                         print >>sys.stderr, (structCentralDir,
    608                         stringCentralDir, create_version,
    609                         zinfo.create_system, extract_version, zinfo.reserved,
    610                         zinfo.flag_bits, zinfo.compress_type, dostime, dosdate,
    611                         zinfo.CRC, compress_size, file_size,
    612                         len(zinfo.filename), len(extra_data), len(zinfo.comment),
    613                         0, zinfo.internal_attr, zinfo.external_attr,
    614                         header_offset)
    615                         raise
    616                     self.fp.write(centdir)
    617                     self.fp.write(filename)
    618                     self.fp.write(extra_data)
    619                     self.fp.write(zinfo.comment)
    620 
    621                 pos2 = self.fp.tell()
    622                 # Write end-of-zip-archive record
    623                 centDirCount = len(self.filelist)
    624                 centDirSize = pos2 - pos1
    625                 centDirOffset = pos1
    626                 requires_zip64 = None
    627                 if centDirCount > ZIP_FILECOUNT_LIMIT:
    628                     requires_zip64 = "Files count"
    629                 elif centDirOffset > ZIP64_LIMIT:
    630                     requires_zip64 = "Central directory offset"
    631                 elif centDirSize > ZIP64_LIMIT:
    632                     requires_zip64 = "Central directory size"
    633                 if requires_zip64:
    634                     # Need to write the ZIP64 end-of-archive records
    635                     if not self._allowZip64:
    636                         raise LargeZipFile(requires_zip64 +
    637                                            " would require ZIP64 extensions")
    638                     zip64endrec = struct.pack(
    639                             structEndArchive64, stringEndArchive64,
    640                             44, 45, 45, 0, 0, centDirCount, centDirCount,
    641                             centDirSize, centDirOffset)
    642                     self.fp.write(zip64endrec)
    643 
    644                     zip64locrec = struct.pack(
    645                             structEndArchive64Locator,
    646                             stringEndArchive64Locator, 0, pos2, 1)
    647                     self.fp.write(zip64locrec)
    648                     centDirCount = min(centDirCount, 0xFFFF)
    649                     centDirSize = min(centDirSize, 0xFFFFFFFF)
    650                     centDirOffset = min(centDirOffset, 0xFFFFFFFF)
    651 
    652                 endrec = struct.pack(structEndArchive, stringEndArchive,
    653                                     0, 0, centDirCount, centDirCount,
    654                                     centDirSize, centDirOffset, len(self._comment))
    655                 self.fp.write(endrec)
    656                 self.fp.write(self._comment)
    657                 self.fp.flush()
    658         finally:
    659             fp = self.fp
    660             self.fp = None
    661             if not self._filePassed:
    662                 fp.close()
    663 
    664 ZipFile
    ZipFilr
    技术分享
      1 class TarFile(object):
      2     """The TarFile Class provides an interface to tar archives.
      3     """
      4 
      5     debug = 0                   # May be set from 0 (no msgs) to 3 (all msgs)
      6 
      7     dereference = False         # If true, add content of linked file to the
      8                                 # tar file, else the link.
      9 
     10     ignore_zeros = False        # If true, skips empty or invalid blocks and
     11                                 # continues processing.
     12 
     13     errorlevel = 1              # If 0, fatal errors only appear in debug
     14                                 # messages (if debug >= 0). If > 0, errors
     15                                 # are passed to the caller as exceptions.
     16 
     17     format = DEFAULT_FORMAT     # The format to use when creating an archive.
     18 
     19     encoding = ENCODING         # Encoding for 8-bit character strings.
     20 
     21     errors = None               # Error handler for unicode conversion.
     22 
     23     tarinfo = TarInfo           # The default TarInfo class to use.
     24 
     25     fileobject = ExFileObject   # The default ExFileObject class to use.
     26 
     27     def __init__(self, name=None, mode="r", fileobj=None, format=None,
     28             tarinfo=None, dereference=None, ignore_zeros=None, encoding=None,
     29             errors=None, pax_headers=None, debug=None, errorlevel=None):
     30         """Open an (uncompressed) tar archive `name‘. `mode‘ is either ‘r‘ to
     31            read from an existing archive, ‘a‘ to append data to an existing
     32            file or ‘w‘ to create a new file overwriting an existing one. `mode‘
     33            defaults to ‘r‘.
     34            If `fileobj‘ is given, it is used for reading or writing data. If it
     35            can be determined, `mode‘ is overridden by `fileobj‘s mode.
     36            `fileobj‘ is not closed, when TarFile is closed.
     37         """
     38         modes = {"r": "rb", "a": "r+b", "w": "wb"}
     39         if mode not in modes:
     40             raise ValueError("mode must be ‘r‘, ‘a‘ or ‘w‘")
     41         self.mode = mode
     42         self._mode = modes[mode]
     43 
     44         if not fileobj:
     45             if self.mode == "a" and not os.path.exists(name):
     46                 # Create nonexistent files in append mode.
     47                 self.mode = "w"
     48                 self._mode = "wb"
     49             fileobj = bltn_open(name, self._mode)
     50             self._extfileobj = False
     51         else:
     52             if name is None and hasattr(fileobj, "name"):
     53                 name = fileobj.name
     54             if hasattr(fileobj, "mode"):
     55                 self._mode = fileobj.mode
     56             self._extfileobj = True
     57         self.name = os.path.abspath(name) if name else None
     58         self.fileobj = fileobj
     59 
     60         # Init attributes.
     61         if format is not None:
     62             self.format = format
     63         if tarinfo is not None:
     64             self.tarinfo = tarinfo
     65         if dereference is not None:
     66             self.dereference = dereference
     67         if ignore_zeros is not None:
     68             self.ignore_zeros = ignore_zeros
     69         if encoding is not None:
     70             self.encoding = encoding
     71 
     72         if errors is not None:
     73             self.errors = errors
     74         elif mode == "r":
     75             self.errors = "utf-8"
     76         else:
     77             self.errors = "strict"
     78 
     79         if pax_headers is not None and self.format == PAX_FORMAT:
     80             self.pax_headers = pax_headers
     81         else:
     82             self.pax_headers = {}
     83 
     84         if debug is not None:
     85             self.debug = debug
     86         if errorlevel is not None:
     87             self.errorlevel = errorlevel
     88 
     89         # Init datastructures.
     90         self.closed = False
     91         self.members = []       # list of members as TarInfo objects
     92         self._loaded = False    # flag if all members have been read
     93         self.offset = self.fileobj.tell()
     94                                 # current position in the archive file
     95         self.inodes = {}        # dictionary caching the inodes of
     96                                 # archive members already added
     97 
     98         try:
     99             if self.mode == "r":
    100                 self.firstmember = None
    101                 self.firstmember = self.next()
    102 
    103             if self.mode == "a":
    104                 # Move to the end of the archive,
    105                 # before the first empty block.
    106                 while True:
    107                     self.fileobj.seek(self.offset)
    108                     try:
    109                         tarinfo = self.tarinfo.fromtarfile(self)
    110                         self.members.append(tarinfo)
    111                     except EOFHeaderError:
    112                         self.fileobj.seek(self.offset)
    113                         break
    114                     except HeaderError, e:
    115                         raise ReadError(str(e))
    116 
    117             if self.mode in "aw":
    118                 self._loaded = True
    119 
    120                 if self.pax_headers:
    121                     buf = self.tarinfo.create_pax_global_header(self.pax_headers.copy())
    122                     self.fileobj.write(buf)
    123                     self.offset += len(buf)
    124         except:
    125             if not self._extfileobj:
    126                 self.fileobj.close()
    127             self.closed = True
    128             raise
    129 
    130     def _getposix(self):
    131         return self.format == USTAR_FORMAT
    132     def _setposix(self, value):
    133         import warnings
    134         warnings.warn("use the format attribute instead", DeprecationWarning,
    135                       2)
    136         if value:
    137             self.format = USTAR_FORMAT
    138         else:
    139             self.format = GNU_FORMAT
    140     posix = property(_getposix, _setposix)
    141 
    142     #--------------------------------------------------------------------------
    143     # Below are the classmethods which act as alternate constructors to the
    144     # TarFile class. The open() method is the only one that is needed for
    145     # public use; it is the "super"-constructor and is able to select an
    146     # adequate "sub"-constructor for a particular compression using the mapping
    147     # from OPEN_METH.
    148     #
    149     # This concept allows one to subclass TarFile without losing the comfort of
    150     # the super-constructor. A sub-constructor is registered and made available
    151     # by adding it to the mapping in OPEN_METH.
    152 
    153     @classmethod
    154     def open(cls, name=None, mode="r", fileobj=None, bufsize=RECORDSIZE, **kwargs):
    155         """Open a tar archive for reading, writing or appending. Return
    156            an appropriate TarFile class.
    157 
    158            mode:
    159            ‘r‘ or ‘r:*‘ open for reading with transparent compression
    160            ‘r:‘         open for reading exclusively uncompressed
    161            ‘r:gz‘       open for reading with gzip compression
    162            ‘r:bz2‘      open for reading with bzip2 compression
    163            ‘a‘ or ‘a:‘  open for appending, creating the file if necessary
    164            ‘w‘ or ‘w:‘  open for writing without compression
    165            ‘w:gz‘       open for writing with gzip compression
    166            ‘w:bz2‘      open for writing with bzip2 compression
    167 
    168            ‘r|*‘        open a stream of tar blocks with transparent compression
    169            ‘r|‘         open an uncompressed stream of tar blocks for reading
    170            ‘r|gz‘       open a gzip compressed stream of tar blocks
    171            ‘r|bz2‘      open a bzip2 compressed stream of tar blocks
    172            ‘w|‘         open an uncompressed stream for writing
    173            ‘w|gz‘       open a gzip compressed stream for writing
    174            ‘w|bz2‘      open a bzip2 compressed stream for writing
    175         """
    176 
    177         if not name and not fileobj:
    178             raise ValueError("nothing to open")
    179 
    180         if mode in ("r", "r:*"):
    181             # Find out which *open() is appropriate for opening the file.
    182             for comptype in cls.OPEN_METH:
    183                 func = getattr(cls, cls.OPEN_METH[comptype])
    184                 if fileobj is not None:
    185                     saved_pos = fileobj.tell()
    186                 try:
    187                     return func(name, "r", fileobj, **kwargs)
    188                 except (ReadError, CompressionError), e:
    189                     if fileobj is not None:
    190                         fileobj.seek(saved_pos)
    191                     continue
    192             raise ReadError("file could not be opened successfully")
    193 
    194         elif ":" in mode:
    195             filemode, comptype = mode.split(":", 1)
    196             filemode = filemode or "r"
    197             comptype = comptype or "tar"
    198 
    199             # Select the *open() function according to
    200             # given compression.
    201             if comptype in cls.OPEN_METH:
    202                 func = getattr(cls, cls.OPEN_METH[comptype])
    203             else:
    204                 raise CompressionError("unknown compression type %r" % comptype)
    205             return func(name, filemode, fileobj, **kwargs)
    206 
    207         elif "|" in mode:
    208             filemode, comptype = mode.split("|", 1)
    209             filemode = filemode or "r"
    210             comptype = comptype or "tar"
    211 
    212             if filemode not in ("r", "w"):
    213                 raise ValueError("mode must be ‘r‘ or ‘w‘")
    214 
    215             stream = _Stream(name, filemode, comptype, fileobj, bufsize)
    216             try:
    217                 t = cls(name, filemode, stream, **kwargs)
    218             except:
    219                 stream.close()
    220                 raise
    221             t._extfileobj = False
    222             return t
    223 
    224         elif mode in ("a", "w"):
    225             return cls.taropen(name, mode, fileobj, **kwargs)
    226 
    227         raise ValueError("undiscernible mode")
    228 
    229     @classmethod
    230     def taropen(cls, name, mode="r", fileobj=None, **kwargs):
    231         """Open uncompressed tar archive name for reading or writing.
    232         """
    233         if mode not in ("r", "a", "w"):
    234             raise ValueError("mode must be ‘r‘, ‘a‘ or ‘w‘")
    235         return cls(name, mode, fileobj, **kwargs)
    236 
    237     @classmethod
    238     def gzopen(cls, name, mode="r", fileobj=None, compresslevel=9, **kwargs):
    239         """Open gzip compressed tar archive name for reading or writing.
    240            Appending is not allowed.
    241         """
    242         if mode not in ("r", "w"):
    243             raise ValueError("mode must be ‘r‘ or ‘w‘")
    244 
    245         try:
    246             import gzip
    247             gzip.GzipFile
    248         except (ImportError, AttributeError):
    249             raise CompressionError("gzip module is not available")
    250 
    251         try:
    252             fileobj = gzip.GzipFile(name, mode, compresslevel, fileobj)
    253         except OSError:
    254             if fileobj is not None and mode == r:
    255                 raise ReadError("not a gzip file")
    256             raise
    257 
    258         try:
    259             t = cls.taropen(name, mode, fileobj, **kwargs)
    260         except IOError:
    261             fileobj.close()
    262             if mode == r:
    263                 raise ReadError("not a gzip file")
    264             raise
    265         except:
    266             fileobj.close()
    267             raise
    268         t._extfileobj = False
    269         return t
    270 
    271     @classmethod
    272     def bz2open(cls, name, mode="r", fileobj=None, compresslevel=9, **kwargs):
    273         """Open bzip2 compressed tar archive name for reading or writing.
    274            Appending is not allowed.
    275         """
    276         if mode not in ("r", "w"):
    277             raise ValueError("mode must be ‘r‘ or ‘w‘.")
    278 
    279         try:
    280             import bz2
    281         except ImportError:
    282             raise CompressionError("bz2 module is not available")
    283 
    284         if fileobj is not None:
    285             fileobj = _BZ2Proxy(fileobj, mode)
    286         else:
    287             fileobj = bz2.BZ2File(name, mode, compresslevel=compresslevel)
    288 
    289         try:
    290             t = cls.taropen(name, mode, fileobj, **kwargs)
    291         except (IOError, EOFError):
    292             fileobj.close()
    293             if mode == r:
    294                 raise ReadError("not a bzip2 file")
    295             raise
    296         except:
    297             fileobj.close()
    298             raise
    299         t._extfileobj = False
    300         return t
    301 
    302     # All *open() methods are registered here.
    303     OPEN_METH = {
    304         "tar": "taropen",   # uncompressed tar
    305         "gz":  "gzopen",    # gzip compressed tar
    306         "bz2": "bz2open"    # bzip2 compressed tar
    307     }
    308 
    309     #--------------------------------------------------------------------------
    310     # The public methods which TarFile provides:
    311 
    312     def close(self):
    313         """Close the TarFile. In write-mode, two finishing zero blocks are
    314            appended to the archive.
    315         """
    316         if self.closed:
    317             return
    318 
    319         if self.mode in "aw":
    320             self.fileobj.write(NUL * (BLOCKSIZE * 2))
    321             self.offset += (BLOCKSIZE * 2)
    322             # fill up the end with zero-blocks
    323             # (like option -b20 for tar does)
    324             blocks, remainder = divmod(self.offset, RECORDSIZE)
    325             if remainder > 0:
    326                 self.fileobj.write(NUL * (RECORDSIZE - remainder))
    327 
    328         if not self._extfileobj:
    329             self.fileobj.close()
    330         self.closed = True
    331 
    332     def getmember(self, name):
    333         """Return a TarInfo object for member `name‘. If `name‘ can not be
    334            found in the archive, KeyError is raised. If a member occurs more
    335            than once in the archive, its last occurrence is assumed to be the
    336            most up-to-date version.
    337         """
    338         tarinfo = self._getmember(name)
    339         if tarinfo is None:
    340             raise KeyError("filename %r not found" % name)
    341         return tarinfo
    342 
    343     def getmembers(self):
    344         """Return the members of the archive as a list of TarInfo objects. The
    345            list has the same order as the members in the archive.
    346         """
    347         self._check()
    348         if not self._loaded:    # if we want to obtain a list of
    349             self._load()        # all members, we first have to
    350                                 # scan the whole archive.
    351         return self.members
    352 
    353     def getnames(self):
    354         """Return the members of the archive as a list of their names. It has
    355            the same order as the list returned by getmembers().
    356         """
    357         return [tarinfo.name for tarinfo in self.getmembers()]
    358 
    359     def gettarinfo(self, name=None, arcname=None, fileobj=None):
    360         """Create a TarInfo object for either the file `name‘ or the file
    361            object `fileobj‘ (using os.fstat on its file descriptor). You can
    362            modify some of the TarInfo‘s attributes before you add it using
    363            addfile(). If given, `arcname‘ specifies an alternative name for the
    364            file in the archive.
    365         """
    366         self._check("aw")
    367 
    368         # When fileobj is given, replace name by
    369         # fileobj‘s real name.
    370         if fileobj is not None:
    371             name = fileobj.name
    372 
    373         # Building the name of the member in the archive.
    374         # Backward slashes are converted to forward slashes,
    375         # Absolute paths are turned to relative paths.
    376         if arcname is None:
    377             arcname = name
    378         drv, arcname = os.path.splitdrive(arcname)
    379         arcname = arcname.replace(os.sep, "/")
    380         arcname = arcname.lstrip("/")
    381 
    382         # Now, fill the TarInfo object with
    383         # information specific for the file.
    384         tarinfo = self.tarinfo()
    385         tarinfo.tarfile = self
    386 
    387         # Use os.stat or os.lstat, depending on platform
    388         # and if symlinks shall be resolved.
    389         if fileobj is None:
    390             if hasattr(os, "lstat") and not self.dereference:
    391                 statres = os.lstat(name)
    392             else:
    393                 statres = os.stat(name)
    394         else:
    395             statres = os.fstat(fileobj.fileno())
    396         linkname = ""
    397 
    398         stmd = statres.st_mode
    399         if stat.S_ISREG(stmd):
    400             inode = (statres.st_ino, statres.st_dev)
    401             if not self.dereference and statres.st_nlink > 1 and 402                     inode in self.inodes and arcname != self.inodes[inode]:
    403                 # Is it a hardlink to an already
    404                 # archived file?
    405                 type = LNKTYPE
    406                 linkname = self.inodes[inode]
    407             else:
    408                 # The inode is added only if its valid.
    409                 # For win32 it is always 0.
    410                 type = REGTYPE
    411                 if inode[0]:
    412                     self.inodes[inode] = arcname
    413         elif stat.S_ISDIR(stmd):
    414             type = DIRTYPE
    415         elif stat.S_ISFIFO(stmd):
    416             type = FIFOTYPE
    417         elif stat.S_ISLNK(stmd):
    418             type = SYMTYPE
    419             linkname = os.readlink(name)
    420         elif stat.S_ISCHR(stmd):
    421             type = CHRTYPE
    422         elif stat.S_ISBLK(stmd):
    423             type = BLKTYPE
    424         else:
    425             return None
    426 
    427         # Fill the TarInfo object with all
    428         # information we can get.
    429         tarinfo.name = arcname
    430         tarinfo.mode = stmd
    431         tarinfo.uid = statres.st_uid
    432         tarinfo.gid = statres.st_gid
    433         if type == REGTYPE:
    434             tarinfo.size = statres.st_size
    435         else:
    436             tarinfo.size = 0L
    437         tarinfo.mtime = statres.st_mtime
    438         tarinfo.type = type
    439         tarinfo.linkname = linkname
    440         if pwd:
    441             try:
    442                 tarinfo.uname = pwd.getpwuid(tarinfo.uid)[0]
    443             except KeyError:
    444                 pass
    445         if grp:
    446             try:
    447                 tarinfo.gname = grp.getgrgid(tarinfo.gid)[0]
    448             except KeyError:
    449                 pass
    450 
    451         if type in (CHRTYPE, BLKTYPE):
    452             if hasattr(os, "major") and hasattr(os, "minor"):
    453                 tarinfo.devmajor = os.major(statres.st_rdev)
    454                 tarinfo.devminor = os.minor(statres.st_rdev)
    455         return tarinfo
    456 
    457     def list(self, verbose=True):
    458         """Print a table of contents to sys.stdout. If `verbose‘ is False, only
    459            the names of the members are printed. If it is True, an `ls -l‘-like
    460            output is produced.
    461         """
    462         self._check()
    463 
    464         for tarinfo in self:
    465             if verbose:
    466                 print filemode(tarinfo.mode),
    467                 print "%s/%s" % (tarinfo.uname or tarinfo.uid,
    468                                  tarinfo.gname or tarinfo.gid),
    469                 if tarinfo.ischr() or tarinfo.isblk():
    470                     print "%10s" % ("%d,%d" 471                                     % (tarinfo.devmajor, tarinfo.devminor)),
    472                 else:
    473                     print "%10d" % tarinfo.size,
    474                 print "%d-%02d-%02d %02d:%02d:%02d" 475                       % time.localtime(tarinfo.mtime)[:6],
    476 
    477             print tarinfo.name + ("/" if tarinfo.isdir() else ""),
    478 
    479             if verbose:
    480                 if tarinfo.issym():
    481                     print "->", tarinfo.linkname,
    482                 if tarinfo.islnk():
    483                     print "link to", tarinfo.linkname,
    484             print
    485 
    486     def add(self, name, arcname=None, recursive=True, exclude=None, filter=None):
    487         """Add the file `name‘ to the archive. `name‘ may be any type of file
    488            (directory, fifo, symbolic link, etc.). If given, `arcname‘
    489            specifies an alternative name for the file in the archive.
    490            Directories are added recursively by default. This can be avoided by
    491            setting `recursive‘ to False. `exclude‘ is a function that should
    492            return True for each filename to be excluded. `filter‘ is a function
    493            that expects a TarInfo object argument and returns the changed
    494            TarInfo object, if it returns None the TarInfo object will be
    495            excluded from the archive.
    496         """
    497         self._check("aw")
    498 
    499         if arcname is None:
    500             arcname = name
    501 
    502         # Exclude pathnames.
    503         if exclude is not None:
    504             import warnings
    505             warnings.warn("use the filter argument instead",
    506                     DeprecationWarning, 2)
    507             if exclude(name):
    508                 self._dbg(2, "tarfile: Excluded %r" % name)
    509                 return
    510 
    511         # Skip if somebody tries to archive the archive...
    512         if self.name is not None and os.path.abspath(name) == self.name:
    513             self._dbg(2, "tarfile: Skipped %r" % name)
    514             return
    515 
    516         self._dbg(1, name)
    517 
    518         # Create a TarInfo object from the file.
    519         tarinfo = self.gettarinfo(name, arcname)
    520 
    521         if tarinfo is None:
    522             self._dbg(1, "tarfile: Unsupported type %r" % name)
    523             return
    524 
    525         # Change or exclude the TarInfo object.
    526         if filter is not None:
    527             tarinfo = filter(tarinfo)
    528             if tarinfo is None:
    529                 self._dbg(2, "tarfile: Excluded %r" % name)
    530                 return
    531 
    532         # Append the tar header and data to the archive.
    533         if tarinfo.isreg():
    534             with bltn_open(name, "rb") as f:
    535                 self.addfile(tarinfo, f)
    536 
    537         elif tarinfo.isdir():
    538             self.addfile(tarinfo)
    539             if recursive:
    540                 for f in os.listdir(name):
    541                     self.add(os.path.join(name, f), os.path.join(arcname, f),
    542                             recursive, exclude, filter)
    543 
    544         else:
    545             self.addfile(tarinfo)
    546 
    547     def addfile(self, tarinfo, fileobj=None):
    548         """Add the TarInfo object `tarinfo‘ to the archive. If `fileobj‘ is
    549            given, tarinfo.size bytes are read from it and added to the archive.
    550            You can create TarInfo objects using gettarinfo().
    551            On Windows platforms, `fileobj‘ should always be opened with mode
    552            ‘rb‘ to avoid irritation about the file size.
    553         """
    554         self._check("aw")
    555 
    556         tarinfo = copy.copy(tarinfo)
    557 
    558         buf = tarinfo.tobuf(self.format, self.encoding, self.errors)
    559         self.fileobj.write(buf)
    560         self.offset += len(buf)
    561 
    562         # If there‘s data to follow, append it.
    563         if fileobj is not None:
    564             copyfileobj(fileobj, self.fileobj, tarinfo.size)
    565             blocks, remainder = divmod(tarinfo.size, BLOCKSIZE)
    566             if remainder > 0:
    567                 self.fileobj.write(NUL * (BLOCKSIZE - remainder))
    568                 blocks += 1
    569             self.offset += blocks * BLOCKSIZE
    570 
    571         self.members.append(tarinfo)
    572 
    573     def extractall(self, path=".", members=None):
    574         """Extract all members from the archive to the current working
    575            directory and set owner, modification time and permissions on
    576            directories afterwards. `path‘ specifies a different directory
    577            to extract to. `members‘ is optional and must be a subset of the
    578            list returned by getmembers().
    579         """
    580         directories = []
    581 
    582         if members is None:
    583             members = self
    584 
    585         for tarinfo in members:
    586             if tarinfo.isdir():
    587                 # Extract directories with a safe mode.
    588                 directories.append(tarinfo)
    589                 tarinfo = copy.copy(tarinfo)
    590                 tarinfo.mode = 0700
    591             self.extract(tarinfo, path)
    592 
    593         # Reverse sort directories.
    594         directories.sort(key=operator.attrgetter(name))
    595         directories.reverse()
    596 
    597         # Set correct owner, mtime and filemode on directories.
    598         for tarinfo in directories:
    599             dirpath = os.path.join(path, tarinfo.name)
    600             try:
    601                 self.chown(tarinfo, dirpath)
    602                 self.utime(tarinfo, dirpath)
    603                 self.chmod(tarinfo, dirpath)
    604             except ExtractError, e:
    605                 if self.errorlevel > 1:
    606                     raise
    607                 else:
    608                     self._dbg(1, "tarfile: %s" % e)
    609 
    610     def extract(self, member, path=""):
    611         """Extract a member from the archive to the current working directory,
    612            using its full name. Its file information is extracted as accurately
    613            as possible. `member‘ may be a filename or a TarInfo object. You can
    614            specify a different directory using `path‘.
    615         """
    616         self._check("r")
    617 
    618         if isinstance(member, basestring):
    619             tarinfo = self.getmember(member)
    620         else:
    621             tarinfo = member
    622 
    623         # Prepare the link target for makelink().
    624         if tarinfo.islnk():
    625             tarinfo._link_target = os.path.join(path, tarinfo.linkname)
    626 
    627         try:
    628             self._extract_member(tarinfo, os.path.join(path, tarinfo.name))
    629         except EnvironmentError, e:
    630             if self.errorlevel > 0:
    631                 raise
    632             else:
    633                 if e.filename is None:
    634                     self._dbg(1, "tarfile: %s" % e.strerror)
    635                 else:
    636                     self._dbg(1, "tarfile: %s %r" % (e.strerror, e.filename))
    637         except ExtractError, e:
    638             if self.errorlevel > 1:
    639                 raise
    640             else:
    641                 self._dbg(1, "tarfile: %s" % e)
    642 
    643     def extractfile(self, member):
    644         """Extract a member from the archive as a file object. `member‘ may be
    645            a filename or a TarInfo object. If `member‘ is a regular file, a
    646            file-like object is returned. If `member‘ is a link, a file-like
    647            object is constructed from the link‘s target. If `member‘ is none of
    648            the above, None is returned.
    649            The file-like object is read-only and provides the following
    650            methods: read(), readline(), readlines(), seek() and tell()
    651         """
    652         self._check("r")
    653 
    654         if isinstance(member, basestring):
    655             tarinfo = self.getmember(member)
    656         else:
    657             tarinfo = member
    658 
    659         if tarinfo.isreg():
    660             return self.fileobject(self, tarinfo)
    661 
    662         elif tarinfo.type not in SUPPORTED_TYPES:
    663             # If a member‘s type is unknown, it is treated as a
    664             # regular file.
    665             return self.fileobject(self, tarinfo)
    666 
    667         elif tarinfo.islnk() or tarinfo.issym():
    668             if isinstance(self.fileobj, _Stream):
    669                 # A small but ugly workaround for the case that someone tries
    670                 # to extract a (sym)link as a file-object from a non-seekable
    671                 # stream of tar blocks.
    672                 raise StreamError("cannot extract (sym)link as file object")
    673             else:
    674                 # A (sym)link‘s file object is its target‘s file object.
    675                 return self.extractfile(self._find_link_target(tarinfo))
    676         else:
    677             # If there‘s no data associated with the member (directory, chrdev,
    678             # blkdev, etc.), return None instead of a file object.
    679             return None
    680 
    681     def _extract_member(self, tarinfo, targetpath):
    682         """Extract the TarInfo object tarinfo to a physical
    683            file called targetpath.
    684         """
    685         # Fetch the TarInfo object for the given name
    686         # and build the destination pathname, replacing
    687         # forward slashes to platform specific separators.
    688         targetpath = targetpath.rstrip("/")
    689         targetpath = targetpath.replace("/", os.sep)
    690 
    691         # Create all upper directories.
    692         upperdirs = os.path.dirname(targetpath)
    693         if upperdirs and not os.path.exists(upperdirs):
    694             # Create directories that are not part of the archive with
    695             # default permissions.
    696             os.makedirs(upperdirs)
    697 
    698         if tarinfo.islnk() or tarinfo.issym():
    699             self._dbg(1, "%s -> %s" % (tarinfo.name, tarinfo.linkname))
    700         else:
    701             self._dbg(1, tarinfo.name)
    702 
    703         if tarinfo.isreg():
    704             self.makefile(tarinfo, targetpath)
    705         elif tarinfo.isdir():
    706             self.makedir(tarinfo, targetpath)
    707         elif tarinfo.isfifo():
    708             self.makefifo(tarinfo, targetpath)
    709         elif tarinfo.ischr() or tarinfo.isblk():
    710             self.makedev(tarinfo, targetpath)
    711         elif tarinfo.islnk() or tarinfo.issym():
    712             self.makelink(tarinfo, targetpath)
    713         elif tarinfo.type not in SUPPORTED_TYPES:
    714             self.makeunknown(tarinfo, targetpath)
    715         else:
    716             self.makefile(tarinfo, targetpath)
    717 
    718         self.chown(tarinfo, targetpath)
    719         if not tarinfo.issym():
    720             self.chmod(tarinfo, targetpath)
    721             self.utime(tarinfo, targetpath)
    722 
    723     #--------------------------------------------------------------------------
    724     # Below are the different file methods. They are called via
    725     # _extract_member() when extract() is called. They can be replaced in a
    726     # subclass to implement other functionality.
    727 
    728     def makedir(self, tarinfo, targetpath):
    729         """Make a directory called targetpath.
    730         """
    731         try:
    732             # Use a safe mode for the directory, the real mode is set
    733             # later in _extract_member().
    734             os.mkdir(targetpath, 0700)
    735         except EnvironmentError, e:
    736             if e.errno != errno.EEXIST:
    737                 raise
    738 
    739     def makefile(self, tarinfo, targetpath):
    740         """Make a file called targetpath.
    741         """
    742         source = self.extractfile(tarinfo)
    743         try:
    744             with bltn_open(targetpath, "wb") as target:
    745                 copyfileobj(source, target)
    746         finally:
    747             source.close()
    748 
    749     def makeunknown(self, tarinfo, targetpath):
    750         """Make a file from a TarInfo object with an unknown type
    751            at targetpath.
    752         """
    753         self.makefile(tarinfo, targetpath)
    754         self._dbg(1, "tarfile: Unknown file type %r, " 755                      "extracted as regular file." % tarinfo.type)
    756 
    757     def makefifo(self, tarinfo, targetpath):
    758         """Make a fifo called targetpath.
    759         """
    760         if hasattr(os, "mkfifo"):
    761             os.mkfifo(targetpath)
    762         else:
    763             raise ExtractError("fifo not supported by system")
    764 
    765     def makedev(self, tarinfo, targetpath):
    766         """Make a character or block device called targetpath.
    767         """
    768         if not hasattr(os, "mknod") or not hasattr(os, "makedev"):
    769             raise ExtractError("special devices not supported by system")
    770 
    771         mode = tarinfo.mode
    772         if tarinfo.isblk():
    773             mode |= stat.S_IFBLK
    774         else:
    775             mode |= stat.S_IFCHR
    776 
    777         os.mknod(targetpath, mode,
    778                  os.makedev(tarinfo.devmajor, tarinfo.devminor))
    779 
    780     def makelink(self, tarinfo, targetpath):
    781         """Make a (symbolic) link called targetpath. If it cannot be created
    782           (platform limitation), we try to make a copy of the referenced file
    783           instead of a link.
    784         """
    785         if hasattr(os, "symlink") and hasattr(os, "link"):
    786             # For systems that support symbolic and hard links.
    787             if tarinfo.issym():
    788                 if os.path.lexists(targetpath):
    789                     os.unlink(targetpath)
    790                 os.symlink(tarinfo.linkname, targetpath)
    791             else:
    792                 # See extract().
    793                 if os.path.exists(tarinfo._link_target):
    794                     if os.path.lexists(targetpath):
    795                         os.unlink(targetpath)
    796                     os.link(tarinfo._link_target, targetpath)
    797                 else:
    798                     self._extract_member(self._find_link_target(tarinfo), targetpath)
    799         else:
    800             try:
    801                 self._extract_member(self._find_link_target(tarinfo), targetpath)
    802             except KeyError:
    803                 raise ExtractError("unable to resolve link inside archive")
    804 
    805     def chown(self, tarinfo, targetpath):
    806         """Set owner of targetpath according to tarinfo.
    807         """
    808         if pwd and hasattr(os, "geteuid") and os.geteuid() == 0:
    809             # We have to be root to do so.
    810             try:
    811                 g = grp.getgrnam(tarinfo.gname)[2]
    812             except KeyError:
    813                 g = tarinfo.gid
    814             try:
    815                 u = pwd.getpwnam(tarinfo.uname)[2]
    816             except KeyError:
    817                 u = tarinfo.uid
    818             try:
    819                 if tarinfo.issym() and hasattr(os, "lchown"):
    820                     os.lchown(targetpath, u, g)
    821                 else:
    822                     if sys.platform != "os2emx":
    823                         os.chown(targetpath, u, g)
    824             except EnvironmentError, e:
    825                 raise ExtractError("could not change owner")
    826 
    827     def chmod(self, tarinfo, targetpath):
    828         """Set file permissions of targetpath according to tarinfo.
    829         """
    830         if hasattr(os, chmod):
    831             try:
    832                 os.chmod(targetpath, tarinfo.mode)
    833             except EnvironmentError, e:
    834                 raise ExtractError("could not change mode")
    835 
    836     def utime(self, tarinfo, targetpath):
    837         """Set modification time of targetpath according to tarinfo.
    838         """
    839         if not hasattr(os, utime):
    840             return
    841         try:
    842             os.utime(targetpath, (tarinfo.mtime, tarinfo.mtime))
    843         except EnvironmentError, e:
    844             raise ExtractError("could not change modification time")
    845 
    846     #--------------------------------------------------------------------------
    847     def next(self):
    848         """Return the next member of the archive as a TarInfo object, when
    849            TarFile is opened for reading. Return None if there is no more
    850            available.
    851         """
    852         self._check("ra")
    853         if self.firstmember is not None:
    854             m = self.firstmember
    855             self.firstmember = None
    856             return m
    857 
    858         # Read the next block.
    859         self.fileobj.seek(self.offset)
    860         tarinfo = None
    861         while True:
    862             try:
    863                 tarinfo = self.tarinfo.fromtarfile(self)
    864             except EOFHeaderError, e:
    865                 if self.ignore_zeros:
    866                     self._dbg(2, "0x%X: %s" % (self.offset, e))
    867                     self.offset += BLOCKSIZE
    868                     continue
    869             except InvalidHeaderError, e:
    870                 if self.ignore_zeros:
    871                     self._dbg(2, "0x%X: %s" % (self.offset, e))
    872                     self.offset += BLOCKSIZE
    873                     continue
    874                 elif self.offset == 0:
    875                     raise ReadError(str(e))
    876             except EmptyHeaderError:
    877                 if self.offset == 0:
    878                     raise ReadError("empty file")
    879             except TruncatedHeaderError, e:
    880                 if self.offset == 0:
    881                     raise ReadError(str(e))
    882             except SubsequentHeaderError, e:
    883                 raise ReadError(str(e))
    884             break
    885 
    886         if tarinfo is not None:
    887             self.members.append(tarinfo)
    888         else:
    889             self._loaded = True
    890 
    891         return tarinfo
    892 
    893     #--------------------------------------------------------------------------
    894     # Little helper methods:
    895 
    896     def _getmember(self, name, tarinfo=None, normalize=False):
    897         """Find an archive member by name from bottom to top.
    898            If tarinfo is given, it is used as the starting point.
    899         """
    900         # Ensure that all members have been loaded.
    901         members = self.getmembers()
    902 
    903         # Limit the member search list up to tarinfo.
    904         if tarinfo is not None:
    905             members = members[:members.index(tarinfo)]
    906 
    907         if normalize:
    908             name = os.path.normpath(name)
    909 
    910         for member in reversed(members):
    911             if normalize:
    912                 member_name = os.path.normpath(member.name)
    913             else:
    914                 member_name = member.name
    915 
    916             if name == member_name:
    917                 return member
    918 
    919     def _load(self):
    920         """Read through the entire archive file and look for readable
    921            members.
    922         """
    923         while True:
    924             tarinfo = self.next()
    925             if tarinfo is None:
    926                 break
    927         self._loaded = True
    928 
    929     def _check(self, mode=None):
    930         """Check if TarFile is still open, and if the operation‘s mode
    931            corresponds to TarFile‘s mode.
    932         """
    933         if self.closed:
    934             raise IOError("%s is closed" % self.__class__.__name__)
    935         if mode is not None and self.mode not in mode:
    936             raise IOError("bad operation for mode %r" % self.mode)
    937 
    938     def _find_link_target(self, tarinfo):
    939         """Find the target member of a symlink or hardlink member in the
    940            archive.
    941         """
    942         if tarinfo.issym():
    943             # Always search the entire archive.
    944             linkname = "/".join(filter(None, (os.path.dirname(tarinfo.name), tarinfo.linkname)))
    945             limit = None
    946         else:
    947             # Search the archive before the link, because a hard link is
    948             # just a reference to an already archived file.
    949             linkname = tarinfo.linkname
    950             limit = tarinfo
    951 
    952         member = self._getmember(linkname, tarinfo=limit, normalize=True)
    953         if member is None:
    954             raise KeyError("linkname %r not found" % linkname)
    955         return member
    956 
    957     def __iter__(self):
    958         """Provide an iterator object.
    959         """
    960         if self._loaded:
    961             return iter(self.members)
    962         else:
    963             return TarIter(self)
    964 
    965     def _dbg(self, level, msg):
    966         """Write debugging output to sys.stderr.
    967         """
    968         if level <= self.debug:
    969             print >> sys.stderr, msg
    970 
    971     def __enter__(self):
    972         self._check()
    973         return self
    974 
    975     def __exit__(self, type, value, traceback):
    976         if type is None:
    977             self.close()
    978         else:
    979             # An exception occurred. We must not call close() because
    980             # it would try to write end-of-archive blocks and padding.
    981             if not self._extfileobj:
    982                 self.fileobj.close()
    983             self.closed = True
    984 # class TarFile
    985 
    986 TarFile
    TarFile

     

Python shutil模块

标签:pes   find file   ensure   error:   script   mkfifo   encrypt   either   setter   

原文地址:http://www.cnblogs.com/DUHEI/p/7516293.html

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