1967 lines
66 KiB
Python
1967 lines
66 KiB
Python
#!/usr/bin/env python
|
|
# -*- coding: iso-8859-1 -*-
|
|
#-------------------------------------------------------------------
|
|
# tarfile.py
|
|
#-------------------------------------------------------------------
|
|
# Copyright (C) 2002 Lars Gustäbel <lars@gustaebel.de>
|
|
# All rights reserved.
|
|
#
|
|
# Permission is hereby granted, free of charge, to any person
|
|
# obtaining a copy of this software and associated documentation
|
|
# files (the "Software"), to deal in the Software without
|
|
# restriction, including without limitation the rights to use,
|
|
# copy, modify, merge, publish, distribute, sublicense, and/or sell
|
|
# copies of the Software, and to permit persons to whom the
|
|
# Software is furnished to do so, subject to the following
|
|
# conditions:
|
|
#
|
|
# The above copyright notice and this permission notice shall be
|
|
# included in all copies or substantial portions of the Software.
|
|
#
|
|
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
|
|
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
|
|
# OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
|
|
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
|
|
# HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
|
|
# WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
|
|
# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
|
|
# OTHER DEALINGS IN THE SOFTWARE.
|
|
#
|
|
"""Read from and write to tar format archives.
|
|
"""
|
|
|
|
__version__ = "$Revision$"
|
|
# $Source$
|
|
|
|
version = "0.6.4"
|
|
__author__ = "Lars Gustäbel (lars@gustaebel.de)"
|
|
__date__ = "$Date$"
|
|
__cvsid__ = "$Id$"
|
|
__credits__ = "Gustavo Niemeyer, Niels Gustäbel, Richard Townsend."
|
|
|
|
#---------
|
|
# Imports
|
|
#---------
|
|
import sys
|
|
import os
|
|
import shutil
|
|
import stat
|
|
import errno
|
|
import time
|
|
import struct
|
|
|
|
if sys.platform == 'mac':
|
|
# This module needs work for MacOS9, especially in the area of pathname
|
|
# handling. In many places it is assumed a simple substitution of / by the
|
|
# local os.path.sep is good enough to convert pathnames, but this does not
|
|
# work with the mac rooted:path:name versus :nonrooted:path:name syntax
|
|
raise ImportError, "tarfile does not work for platform==mac"
|
|
|
|
try:
|
|
import grp, pwd
|
|
except ImportError:
|
|
grp = pwd = None
|
|
|
|
# from tarfile import *
|
|
__all__ = ["TarFile", "TarInfo", "is_tarfile", "TarError"]
|
|
|
|
#---------------------------------------------------------
|
|
# tar constants
|
|
#---------------------------------------------------------
|
|
NUL = "\0" # the null character
|
|
BLOCKSIZE = 512 # length of processing blocks
|
|
RECORDSIZE = BLOCKSIZE * 20 # length of records
|
|
MAGIC = "ustar" # magic tar string
|
|
VERSION = "00" # version number
|
|
|
|
LENGTH_NAME = 100 # maximum length of a filename
|
|
LENGTH_LINK = 100 # maximum length of a linkname
|
|
LENGTH_PREFIX = 155 # maximum length of the prefix field
|
|
MAXSIZE_MEMBER = 077777777777L # maximum size of a file (11 octal digits)
|
|
|
|
REGTYPE = "0" # regular file
|
|
AREGTYPE = "\0" # regular file
|
|
LNKTYPE = "1" # link (inside tarfile)
|
|
SYMTYPE = "2" # symbolic link
|
|
CHRTYPE = "3" # character special device
|
|
BLKTYPE = "4" # block special device
|
|
DIRTYPE = "5" # directory
|
|
FIFOTYPE = "6" # fifo special device
|
|
CONTTYPE = "7" # contiguous file
|
|
|
|
GNUTYPE_LONGNAME = "L" # GNU tar extension for longnames
|
|
GNUTYPE_LONGLINK = "K" # GNU tar extension for longlink
|
|
GNUTYPE_SPARSE = "S" # GNU tar extension for sparse file
|
|
|
|
#---------------------------------------------------------
|
|
# tarfile constants
|
|
#---------------------------------------------------------
|
|
SUPPORTED_TYPES = (REGTYPE, AREGTYPE, LNKTYPE, # file types that tarfile
|
|
SYMTYPE, DIRTYPE, FIFOTYPE, # can cope with.
|
|
CONTTYPE, CHRTYPE, BLKTYPE,
|
|
GNUTYPE_LONGNAME, GNUTYPE_LONGLINK,
|
|
GNUTYPE_SPARSE)
|
|
|
|
REGULAR_TYPES = (REGTYPE, AREGTYPE, # file types that somehow
|
|
CONTTYPE, GNUTYPE_SPARSE) # represent regular files
|
|
|
|
#---------------------------------------------------------
|
|
# Bits used in the mode field, values in octal.
|
|
#---------------------------------------------------------
|
|
S_IFLNK = 0120000 # symbolic link
|
|
S_IFREG = 0100000 # regular file
|
|
S_IFBLK = 0060000 # block device
|
|
S_IFDIR = 0040000 # directory
|
|
S_IFCHR = 0020000 # character device
|
|
S_IFIFO = 0010000 # fifo
|
|
|
|
TSUID = 04000 # set UID on execution
|
|
TSGID = 02000 # set GID on execution
|
|
TSVTX = 01000 # reserved
|
|
|
|
TUREAD = 0400 # read by owner
|
|
TUWRITE = 0200 # write by owner
|
|
TUEXEC = 0100 # execute/search by owner
|
|
TGREAD = 0040 # read by group
|
|
TGWRITE = 0020 # write by group
|
|
TGEXEC = 0010 # execute/search by group
|
|
TOREAD = 0004 # read by other
|
|
TOWRITE = 0002 # write by other
|
|
TOEXEC = 0001 # execute/search by other
|
|
|
|
#---------------------------------------------------------
|
|
# Some useful functions
|
|
#---------------------------------------------------------
|
|
def nts(s):
|
|
"""Convert a null-terminated string buffer to a python string.
|
|
"""
|
|
return s.rstrip(NUL)
|
|
|
|
def calc_chksum(buf):
|
|
"""Calculate the checksum for a member's header. It's a simple addition
|
|
of all bytes, treating the chksum field as if filled with spaces.
|
|
buf is a 512 byte long string buffer which holds the header.
|
|
"""
|
|
chk = 256 # chksum field is treated as blanks,
|
|
# so the initial value is 8 * ord(" ")
|
|
for c in buf[:148]: chk += ord(c) # sum up all bytes before chksum
|
|
for c in buf[156:]: chk += ord(c) # sum up all bytes after chksum
|
|
return chk
|
|
|
|
def copyfileobj(src, dst, length=None):
|
|
"""Copy length bytes from fileobj src to fileobj dst.
|
|
If length is None, copy the entire content.
|
|
"""
|
|
if length == 0:
|
|
return
|
|
if length is None:
|
|
shutil.copyfileobj(src, dst)
|
|
return
|
|
|
|
BUFSIZE = 16 * 1024
|
|
blocks, remainder = divmod(length, BUFSIZE)
|
|
for b in xrange(blocks):
|
|
buf = src.read(BUFSIZE)
|
|
if len(buf) < BUFSIZE:
|
|
raise IOError, "end of file reached"
|
|
dst.write(buf)
|
|
|
|
if remainder != 0:
|
|
buf = src.read(remainder)
|
|
if len(buf) < remainder:
|
|
raise IOError, "end of file reached"
|
|
dst.write(buf)
|
|
return
|
|
|
|
filemode_table = (
|
|
((S_IFLNK, "l"),
|
|
(S_IFREG, "-"),
|
|
(S_IFBLK, "b"),
|
|
(S_IFDIR, "d"),
|
|
(S_IFCHR, "c"),
|
|
(S_IFIFO, "p")),
|
|
|
|
((TUREAD, "r"),),
|
|
((TUWRITE, "w"),),
|
|
((TUEXEC|TSUID, "s"),
|
|
(TSUID, "S"),
|
|
(TUEXEC, "x")),
|
|
|
|
((TGREAD, "r"),),
|
|
((TGWRITE, "w"),),
|
|
((TGEXEC|TSGID, "s"),
|
|
(TSGID, "S"),
|
|
(TGEXEC, "x")),
|
|
|
|
((TOREAD, "r"),),
|
|
((TOWRITE, "w"),),
|
|
((TOEXEC|TSVTX, "t"),
|
|
(TSVTX, "T"),
|
|
(TOEXEC, "x"))
|
|
)
|
|
|
|
def filemode(mode):
|
|
"""Convert a file's mode to a string of the form
|
|
-rwxrwxrwx.
|
|
Used by TarFile.list()
|
|
"""
|
|
perm = []
|
|
for table in filemode_table:
|
|
for bit, char in table:
|
|
if mode & bit == bit:
|
|
perm.append(char)
|
|
break
|
|
else:
|
|
perm.append("-")
|
|
return "".join(perm)
|
|
|
|
if os.sep != "/":
|
|
normpath = lambda path: os.path.normpath(path).replace(os.sep, "/")
|
|
else:
|
|
normpath = os.path.normpath
|
|
|
|
class TarError(Exception):
|
|
"""Base exception."""
|
|
pass
|
|
class ExtractError(TarError):
|
|
"""General exception for extract errors."""
|
|
pass
|
|
class ReadError(TarError):
|
|
"""Exception for unreadble tar archives."""
|
|
pass
|
|
class CompressionError(TarError):
|
|
"""Exception for unavailable compression methods."""
|
|
pass
|
|
class StreamError(TarError):
|
|
"""Exception for unsupported operations on stream-like TarFiles."""
|
|
pass
|
|
|
|
#---------------------------
|
|
# internal stream interface
|
|
#---------------------------
|
|
class _LowLevelFile:
|
|
"""Low-level file object. Supports reading and writing.
|
|
It is used instead of a regular file object for streaming
|
|
access.
|
|
"""
|
|
|
|
def __init__(self, name, mode):
|
|
mode = {
|
|
"r": os.O_RDONLY,
|
|
"w": os.O_WRONLY | os.O_CREAT | os.O_TRUNC,
|
|
}[mode]
|
|
if hasattr(os, "O_BINARY"):
|
|
mode |= os.O_BINARY
|
|
self.fd = os.open(name, mode)
|
|
|
|
def close(self):
|
|
os.close(self.fd)
|
|
|
|
def read(self, size):
|
|
return os.read(self.fd, size)
|
|
|
|
def write(self, s):
|
|
os.write(self.fd, s)
|
|
|
|
class _Stream:
|
|
"""Class that serves as an adapter between TarFile and
|
|
a stream-like object. The stream-like object only
|
|
needs to have a read() or write() method and is accessed
|
|
blockwise. Use of gzip or bzip2 compression is possible.
|
|
A stream-like object could be for example: sys.stdin,
|
|
sys.stdout, a socket, a tape device etc.
|
|
|
|
_Stream is intended to be used only internally.
|
|
"""
|
|
|
|
def __init__(self, name, mode, type, fileobj, bufsize):
|
|
"""Construct a _Stream object.
|
|
"""
|
|
self._extfileobj = True
|
|
if fileobj is None:
|
|
fileobj = _LowLevelFile(name, mode)
|
|
self._extfileobj = False
|
|
|
|
self.name = name or ""
|
|
self.mode = mode
|
|
self.type = type
|
|
self.fileobj = fileobj
|
|
self.bufsize = bufsize
|
|
self.buf = ""
|
|
self.pos = 0L
|
|
self.closed = False
|
|
|
|
if type == "gz":
|
|
try:
|
|
import zlib
|
|
except ImportError:
|
|
raise CompressionError, "zlib module is not available"
|
|
self.zlib = zlib
|
|
self.crc = zlib.crc32("")
|
|
if mode == "r":
|
|
self._init_read_gz()
|
|
else:
|
|
self._init_write_gz()
|
|
|
|
if type == "bz2":
|
|
try:
|
|
import bz2
|
|
except ImportError:
|
|
raise CompressionError, "bz2 module is not available"
|
|
if mode == "r":
|
|
self.dbuf = ""
|
|
self.cmp = bz2.BZ2Decompressor()
|
|
else:
|
|
self.cmp = bz2.BZ2Compressor()
|
|
|
|
def __del__(self):
|
|
if not self.closed:
|
|
self.close()
|
|
|
|
def _init_write_gz(self):
|
|
"""Initialize for writing with gzip compression.
|
|
"""
|
|
self.cmp = self.zlib.compressobj(9, self.zlib.DEFLATED,
|
|
-self.zlib.MAX_WBITS,
|
|
self.zlib.DEF_MEM_LEVEL,
|
|
0)
|
|
timestamp = struct.pack("<L", long(time.time()))
|
|
self.__write("\037\213\010\010%s\002\377" % timestamp)
|
|
if self.name.endswith(".gz"):
|
|
self.name = self.name[:-3]
|
|
self.__write(self.name + NUL)
|
|
|
|
def write(self, s):
|
|
"""Write string s to the stream.
|
|
"""
|
|
if self.type == "gz":
|
|
self.crc = self.zlib.crc32(s, self.crc)
|
|
self.pos += len(s)
|
|
if self.type != "tar":
|
|
s = self.cmp.compress(s)
|
|
self.__write(s)
|
|
|
|
def __write(self, s):
|
|
"""Write string s to the stream if a whole new block
|
|
is ready to be written.
|
|
"""
|
|
self.buf += s
|
|
while len(self.buf) > self.bufsize:
|
|
self.fileobj.write(self.buf[:self.bufsize])
|
|
self.buf = self.buf[self.bufsize:]
|
|
|
|
def close(self):
|
|
"""Close the _Stream object. No operation should be
|
|
done on it afterwards.
|
|
"""
|
|
if self.closed:
|
|
return
|
|
|
|
if self.mode == "w" and self.type != "tar":
|
|
self.buf += self.cmp.flush()
|
|
if self.mode == "w" and self.buf:
|
|
self.fileobj.write(self.buf)
|
|
self.buf = ""
|
|
if self.type == "gz":
|
|
self.fileobj.write(struct.pack("<l", self.crc))
|
|
self.fileobj.write(struct.pack("<L", self.pos & 0xffffFFFFL))
|
|
|
|
if not self._extfileobj:
|
|
self.fileobj.close()
|
|
|
|
self.closed = True
|
|
|
|
def _init_read_gz(self):
|
|
"""Initialize for reading a gzip compressed fileobj.
|
|
"""
|
|
self.cmp = self.zlib.decompressobj(-self.zlib.MAX_WBITS)
|
|
self.dbuf = ""
|
|
|
|
# taken from gzip.GzipFile with some alterations
|
|
if self.__read(2) != "\037\213":
|
|
raise ReadError, "not a gzip file"
|
|
if self.__read(1) != "\010":
|
|
raise CompressionError, "unsupported compression method"
|
|
|
|
flag = ord(self.__read(1))
|
|
self.__read(6)
|
|
|
|
if flag & 4:
|
|
xlen = ord(self.__read(1)) + 256 * ord(self.__read(1))
|
|
self.read(xlen)
|
|
if flag & 8:
|
|
while True:
|
|
s = self.__read(1)
|
|
if not s or s == NUL:
|
|
break
|
|
if flag & 16:
|
|
while True:
|
|
s = self.__read(1)
|
|
if not s or s == NUL:
|
|
break
|
|
if flag & 2:
|
|
self.__read(2)
|
|
|
|
def tell(self):
|
|
"""Return the stream's file pointer position.
|
|
"""
|
|
return self.pos
|
|
|
|
def seek(self, pos=0):
|
|
"""Set the stream's file pointer to pos. Negative seeking
|
|
is forbidden.
|
|
"""
|
|
if pos - self.pos >= 0:
|
|
blocks, remainder = divmod(pos - self.pos, self.bufsize)
|
|
for i in xrange(blocks):
|
|
self.read(self.bufsize)
|
|
self.read(remainder)
|
|
else:
|
|
raise StreamError, "seeking backwards is not allowed"
|
|
return self.pos
|
|
|
|
def read(self, size=None):
|
|
"""Return the next size number of bytes from the stream.
|
|
If size is not defined, return all bytes of the stream
|
|
up to EOF.
|
|
"""
|
|
if size is None:
|
|
t = []
|
|
while True:
|
|
buf = self._read(self.bufsize)
|
|
if not buf:
|
|
break
|
|
t.append(buf)
|
|
buf = "".join(t)
|
|
else:
|
|
buf = self._read(size)
|
|
self.pos += len(buf)
|
|
return buf
|
|
|
|
def _read(self, size):
|
|
"""Return size bytes from the stream.
|
|
"""
|
|
if self.type == "tar":
|
|
return self.__read(size)
|
|
|
|
c = len(self.dbuf)
|
|
t = [self.dbuf]
|
|
while c < size:
|
|
buf = self.__read(self.bufsize)
|
|
if not buf:
|
|
break
|
|
buf = self.cmp.decompress(buf)
|
|
t.append(buf)
|
|
c += len(buf)
|
|
t = "".join(t)
|
|
self.dbuf = t[size:]
|
|
return t[:size]
|
|
|
|
def __read(self, size):
|
|
"""Return size bytes from stream. If internal buffer is empty,
|
|
read another block from the stream.
|
|
"""
|
|
c = len(self.buf)
|
|
t = [self.buf]
|
|
while c < size:
|
|
buf = self.fileobj.read(self.bufsize)
|
|
if not buf:
|
|
break
|
|
t.append(buf)
|
|
c += len(buf)
|
|
t = "".join(t)
|
|
self.buf = t[size:]
|
|
return t[:size]
|
|
# class _Stream
|
|
|
|
#------------------------
|
|
# Extraction file object
|
|
#------------------------
|
|
class ExFileObject(object):
|
|
"""File-like object for reading an archive member.
|
|
Is returned by TarFile.extractfile(). Support for
|
|
sparse files included.
|
|
"""
|
|
|
|
def __init__(self, tarfile, tarinfo):
|
|
self.fileobj = tarfile.fileobj
|
|
self.name = tarinfo.name
|
|
self.mode = "r"
|
|
self.closed = False
|
|
self.offset = tarinfo.offset_data
|
|
self.size = tarinfo.size
|
|
self.pos = 0L
|
|
self.linebuffer = ""
|
|
if tarinfo.issparse():
|
|
self.sparse = tarinfo.sparse
|
|
self.read = self._readsparse
|
|
else:
|
|
self.read = self._readnormal
|
|
|
|
def __read(self, size):
|
|
"""Overloadable read method.
|
|
"""
|
|
return self.fileobj.read(size)
|
|
|
|
def readline(self, size=-1):
|
|
"""Read a line with approx. size. If size is negative,
|
|
read a whole line. readline() and read() must not
|
|
be mixed up (!).
|
|
"""
|
|
if size < 0:
|
|
size = sys.maxint
|
|
|
|
nl = self.linebuffer.find("\n")
|
|
if nl >= 0:
|
|
nl = min(nl, size)
|
|
else:
|
|
size -= len(self.linebuffer)
|
|
while (nl < 0 and size > 0):
|
|
buf = self.read(min(size, 100))
|
|
if not buf:
|
|
break
|
|
self.linebuffer += buf
|
|
size -= len(buf)
|
|
nl = self.linebuffer.find("\n")
|
|
if nl == -1:
|
|
s = self.linebuffer
|
|
self.linebuffer = ""
|
|
return s
|
|
buf = self.linebuffer[:nl]
|
|
self.linebuffer = self.linebuffer[nl + 1:]
|
|
while buf[-1:] == "\r":
|
|
buf = buf[:-1]
|
|
return buf + "\n"
|
|
|
|
def readlines(self):
|
|
"""Return a list with all (following) lines.
|
|
"""
|
|
result = []
|
|
while True:
|
|
line = self.readline()
|
|
if not line: break
|
|
result.append(line)
|
|
return result
|
|
|
|
def _readnormal(self, size=None):
|
|
"""Read operation for regular files.
|
|
"""
|
|
if self.closed:
|
|
raise ValueError, "file is closed"
|
|
self.fileobj.seek(self.offset + self.pos)
|
|
bytesleft = self.size - self.pos
|
|
if size is None:
|
|
bytestoread = bytesleft
|
|
else:
|
|
bytestoread = min(size, bytesleft)
|
|
self.pos += bytestoread
|
|
return self.__read(bytestoread)
|
|
|
|
def _readsparse(self, size=None):
|
|
"""Read operation for sparse files.
|
|
"""
|
|
if self.closed:
|
|
raise ValueError, "file is closed"
|
|
|
|
if size is None:
|
|
size = self.size - self.pos
|
|
|
|
data = []
|
|
while size > 0:
|
|
buf = self._readsparsesection(size)
|
|
if not buf:
|
|
break
|
|
size -= len(buf)
|
|
data.append(buf)
|
|
return "".join(data)
|
|
|
|
def _readsparsesection(self, size):
|
|
"""Read a single section of a sparse file.
|
|
"""
|
|
section = self.sparse.find(self.pos)
|
|
|
|
if section is None:
|
|
return ""
|
|
|
|
toread = min(size, section.offset + section.size - self.pos)
|
|
if isinstance(section, _data):
|
|
realpos = section.realpos + self.pos - section.offset
|
|
self.pos += toread
|
|
self.fileobj.seek(self.offset + realpos)
|
|
return self.__read(toread)
|
|
else:
|
|
self.pos += toread
|
|
return NUL * toread
|
|
|
|
def tell(self):
|
|
"""Return the current file position.
|
|
"""
|
|
return self.pos
|
|
|
|
def seek(self, pos, whence=0):
|
|
"""Seek to a position in the file.
|
|
"""
|
|
self.linebuffer = ""
|
|
if whence == 0:
|
|
self.pos = min(max(pos, 0), self.size)
|
|
if whence == 1:
|
|
if pos < 0:
|
|
self.pos = max(self.pos + pos, 0)
|
|
else:
|
|
self.pos = min(self.pos + pos, self.size)
|
|
if whence == 2:
|
|
self.pos = max(min(self.size + pos, self.size), 0)
|
|
|
|
def close(self):
|
|
"""Close the file object.
|
|
"""
|
|
self.closed = True
|
|
#class ExFileObject
|
|
|
|
#------------------
|
|
# Exported Classes
|
|
#------------------
|
|
class TarInfo(object):
|
|
"""Informational class which holds the details about an
|
|
archive member given by a tar header block.
|
|
TarInfo objects are returned by TarFile.getmember(),
|
|
TarFile.getmembers() and TarFile.gettarinfo() and are
|
|
usually created internally.
|
|
"""
|
|
|
|
def __init__(self, name=""):
|
|
"""Construct a TarInfo object. name is the optional name
|
|
of the member.
|
|
"""
|
|
|
|
self.name = name # member name (dirnames must end with '/')
|
|
self.mode = 0666 # file permissions
|
|
self.uid = 0 # user id
|
|
self.gid = 0 # group id
|
|
self.size = 0 # file size
|
|
self.mtime = 0 # modification time
|
|
self.chksum = 0 # header checksum
|
|
self.type = REGTYPE # member type
|
|
self.linkname = "" # link name
|
|
self.uname = "user" # user name
|
|
self.gname = "group" # group name
|
|
self.devmajor = 0 #-
|
|
self.devminor = 0 #-for use with CHRTYPE and BLKTYPE
|
|
self.prefix = "" # prefix to filename or holding information
|
|
# about sparse files
|
|
|
|
self.offset = 0 # the tar header starts here
|
|
self.offset_data = 0 # the file's data starts here
|
|
|
|
def __repr__(self):
|
|
return "<%s %r at %#x>" % (self.__class__.__name__,self.name,id(self))
|
|
|
|
def frombuf(cls, buf):
|
|
"""Construct a TarInfo object from a 512 byte string buffer.
|
|
"""
|
|
tarinfo = cls()
|
|
tarinfo.name = nts(buf[0:100])
|
|
tarinfo.mode = int(buf[100:108], 8)
|
|
tarinfo.uid = int(buf[108:116],8)
|
|
tarinfo.gid = int(buf[116:124],8)
|
|
|
|
# There are two possible codings for the size field we
|
|
# have to discriminate, see comment in tobuf() below.
|
|
if buf[124] != chr(0200):
|
|
tarinfo.size = long(buf[124:136], 8)
|
|
else:
|
|
tarinfo.size = 0L
|
|
for i in range(11):
|
|
tarinfo.size <<= 8
|
|
tarinfo.size += ord(buf[125 + i])
|
|
|
|
tarinfo.mtime = long(buf[136:148], 8)
|
|
tarinfo.chksum = int(buf[148:156], 8)
|
|
tarinfo.type = buf[156:157]
|
|
tarinfo.linkname = nts(buf[157:257])
|
|
tarinfo.uname = nts(buf[265:297])
|
|
tarinfo.gname = nts(buf[297:329])
|
|
try:
|
|
tarinfo.devmajor = int(buf[329:337], 8)
|
|
tarinfo.devminor = int(buf[337:345], 8)
|
|
except ValueError:
|
|
tarinfo.devmajor = tarinfo.devmajor = 0
|
|
tarinfo.prefix = buf[345:500]
|
|
|
|
# The prefix field is used for filenames > 100 in
|
|
# the POSIX standard.
|
|
# name = prefix + '/' + name
|
|
if tarinfo.type != GNUTYPE_SPARSE:
|
|
tarinfo.name = normpath(os.path.join(nts(tarinfo.prefix), tarinfo.name))
|
|
|
|
# Directory names should have a '/' at the end.
|
|
if tarinfo.isdir() and tarinfo.name[-1:] != "/":
|
|
tarinfo.name += "/"
|
|
return tarinfo
|
|
|
|
frombuf = classmethod(frombuf)
|
|
|
|
def tobuf(self):
|
|
"""Return a tar header block as a 512 byte string.
|
|
"""
|
|
# Prefer the size to be encoded as 11 octal ascii digits
|
|
# which is the most portable. If the size exceeds this
|
|
# limit (>= 8 GB), encode it as an 88-bit value which is
|
|
# a GNU tar feature.
|
|
if self.size <= MAXSIZE_MEMBER:
|
|
size = "%011o" % self.size
|
|
else:
|
|
s = self.size
|
|
size = ""
|
|
for i in range(11):
|
|
size = chr(s & 0377) + size
|
|
s >>= 8
|
|
size = chr(0200) + size
|
|
|
|
# The following code was contributed by Detlef Lannert.
|
|
parts = []
|
|
for value, fieldsize in (
|
|
(self.name, 100),
|
|
("%07o" % (self.mode & 07777), 8),
|
|
("%07o" % self.uid, 8),
|
|
("%07o" % self.gid, 8),
|
|
(size, 12),
|
|
("%011o" % self.mtime, 12),
|
|
(" ", 8),
|
|
(self.type, 1),
|
|
(self.linkname, 100),
|
|
(MAGIC, 6),
|
|
(VERSION, 2),
|
|
(self.uname, 32),
|
|
(self.gname, 32),
|
|
("%07o" % self.devmajor, 8),
|
|
("%07o" % self.devminor, 8),
|
|
(self.prefix, 155)
|
|
):
|
|
l = len(value)
|
|
parts.append(value[:fieldsize] + (fieldsize - l) * NUL)
|
|
|
|
buf = "".join(parts)
|
|
chksum = calc_chksum(buf)
|
|
buf = buf[:148] + "%06o\0" % chksum + buf[155:]
|
|
buf += (BLOCKSIZE - len(buf)) * NUL
|
|
self.buf = buf
|
|
return buf
|
|
|
|
def isreg(self):
|
|
return self.type in REGULAR_TYPES
|
|
def isfile(self):
|
|
return self.isreg()
|
|
def isdir(self):
|
|
return self.type == DIRTYPE
|
|
def issym(self):
|
|
return self.type == SYMTYPE
|
|
def islnk(self):
|
|
return self.type == LNKTYPE
|
|
def ischr(self):
|
|
return self.type == CHRTYPE
|
|
def isblk(self):
|
|
return self.type == BLKTYPE
|
|
def isfifo(self):
|
|
return self.type == FIFOTYPE
|
|
def issparse(self):
|
|
return self.type == GNUTYPE_SPARSE
|
|
def isdev(self):
|
|
return self.type in (CHRTYPE, BLKTYPE, FIFOTYPE)
|
|
# class TarInfo
|
|
|
|
class TarFile(object):
|
|
"""The TarFile Class provides an interface to tar archives.
|
|
"""
|
|
|
|
debug = 0 # May be set from 0 (no msgs) to 3 (all msgs)
|
|
|
|
dereference = False # If true, add content of linked file to the
|
|
# tar file, else the link.
|
|
|
|
ignore_zeros = False # If true, skips empty or invalid blocks and
|
|
# continues processing.
|
|
|
|
errorlevel = 0 # If 0, fatal errors only appear in debug
|
|
# messages (if debug >= 0). If > 0, errors
|
|
# are passed to the caller as exceptions.
|
|
|
|
posix = False # If True, generates POSIX.1-1990-compliant
|
|
# archives (no GNU extensions!)
|
|
|
|
fileobject = ExFileObject
|
|
|
|
def __init__(self, name=None, mode="r", fileobj=None):
|
|
"""Open an (uncompressed) tar archive `name'. `mode' is either 'r' to
|
|
read from an existing archive, 'a' to append data to an existing
|
|
file or 'w' to create a new file overwriting an existing one. `mode'
|
|
defaults to 'r'.
|
|
If `fileobj' is given, it is used for reading or writing data. If it
|
|
can be determined, `mode' is overridden by `fileobj's mode.
|
|
`fileobj' is not closed, when TarFile is closed.
|
|
"""
|
|
self.name = name
|
|
|
|
if len(mode) > 1 or mode not in "raw":
|
|
raise ValueError, "mode must be 'r', 'a' or 'w'"
|
|
self._mode = mode
|
|
self.mode = {"r": "rb", "a": "r+b", "w": "wb"}[mode]
|
|
|
|
if not fileobj:
|
|
fileobj = file(self.name, self.mode)
|
|
self._extfileobj = False
|
|
else:
|
|
if self.name is None and hasattr(fileobj, "name"):
|
|
self.name = fileobj.name
|
|
if hasattr(fileobj, "mode"):
|
|
self.mode = fileobj.mode
|
|
self._extfileobj = True
|
|
self.fileobj = fileobj
|
|
|
|
# Init datastructures
|
|
self.closed = False
|
|
self.members = [] # list of members as TarInfo objects
|
|
self._loaded = False # flag if all members have been read
|
|
self.offset = 0L # current position in the archive file
|
|
self.inodes = {} # dictionary caching the inodes of
|
|
# archive members already added
|
|
|
|
if self._mode == "r":
|
|
self.firstmember = None
|
|
self.firstmember = self.next()
|
|
|
|
if self._mode == "a":
|
|
# Move to the end of the archive,
|
|
# before the first empty block.
|
|
self.firstmember = None
|
|
while True:
|
|
try:
|
|
tarinfo = self.next()
|
|
except ReadError:
|
|
self.fileobj.seek(0)
|
|
break
|
|
if tarinfo is None:
|
|
self.fileobj.seek(- BLOCKSIZE, 1)
|
|
break
|
|
|
|
if self._mode in "aw":
|
|
self._loaded = True
|
|
|
|
#--------------------------------------------------------------------------
|
|
# Below are the classmethods which act as alternate constructors to the
|
|
# TarFile class. The open() method is the only one that is needed for
|
|
# public use; it is the "super"-constructor and is able to select an
|
|
# adequate "sub"-constructor for a particular compression using the mapping
|
|
# from OPEN_METH.
|
|
#
|
|
# This concept allows one to subclass TarFile without losing the comfort of
|
|
# the super-constructor. A sub-constructor is registered and made available
|
|
# by adding it to the mapping in OPEN_METH.
|
|
|
|
def open(cls, name=None, mode="r", fileobj=None, bufsize=20*512):
|
|
"""Open a tar archive for reading, writing or appending. Return
|
|
an appropriate TarFile class.
|
|
|
|
mode:
|
|
'r' open for reading with transparent compression
|
|
'r:' open for reading exclusively uncompressed
|
|
'r:gz' open for reading with gzip compression
|
|
'r:bz2' open for reading with bzip2 compression
|
|
'a' or 'a:' open for appending
|
|
'w' or 'w:' open for writing without compression
|
|
'w:gz' open for writing with gzip compression
|
|
'w:bz2' open for writing with bzip2 compression
|
|
'r|' open an uncompressed stream of tar blocks for reading
|
|
'r|gz' open a gzip compressed stream of tar blocks
|
|
'r|bz2' open a bzip2 compressed stream of tar blocks
|
|
'w|' open an uncompressed stream for writing
|
|
'w|gz' open a gzip compressed stream for writing
|
|
'w|bz2' open a bzip2 compressed stream for writing
|
|
"""
|
|
|
|
if not name and not fileobj:
|
|
raise ValueError, "nothing to open"
|
|
|
|
if ":" in mode:
|
|
filemode, comptype = mode.split(":", 1)
|
|
filemode = filemode or "r"
|
|
comptype = comptype or "tar"
|
|
|
|
# Select the *open() function according to
|
|
# given compression.
|
|
if comptype in cls.OPEN_METH:
|
|
func = getattr(cls, cls.OPEN_METH[comptype])
|
|
else:
|
|
raise CompressionError, "unknown compression type %r" % comptype
|
|
return func(name, filemode, fileobj)
|
|
|
|
elif "|" in mode:
|
|
filemode, comptype = mode.split("|", 1)
|
|
filemode = filemode or "r"
|
|
comptype = comptype or "tar"
|
|
|
|
if filemode not in "rw":
|
|
raise ValueError, "mode must be 'r' or 'w'"
|
|
|
|
t = cls(name, filemode,
|
|
_Stream(name, filemode, comptype, fileobj, bufsize))
|
|
t._extfileobj = False
|
|
return t
|
|
|
|
elif mode == "r":
|
|
# Find out which *open() is appropriate for opening the file.
|
|
for comptype in cls.OPEN_METH:
|
|
func = getattr(cls, cls.OPEN_METH[comptype])
|
|
try:
|
|
return func(name, "r", fileobj)
|
|
except (ReadError, CompressionError):
|
|
continue
|
|
raise ReadError, "file could not be opened successfully"
|
|
|
|
elif mode in "aw":
|
|
return cls.taropen(name, mode, fileobj)
|
|
|
|
raise ValueError, "undiscernible mode"
|
|
|
|
open = classmethod(open)
|
|
|
|
def taropen(cls, name, mode="r", fileobj=None):
|
|
"""Open uncompressed tar archive name for reading or writing.
|
|
"""
|
|
if len(mode) > 1 or mode not in "raw":
|
|
raise ValueError, "mode must be 'r', 'a' or 'w'"
|
|
return cls(name, mode, fileobj)
|
|
|
|
taropen = classmethod(taropen)
|
|
|
|
def gzopen(cls, name, mode="r", fileobj=None, compresslevel=9):
|
|
"""Open gzip compressed tar archive name for reading or writing.
|
|
Appending is not allowed.
|
|
"""
|
|
if len(mode) > 1 or mode not in "rw":
|
|
raise ValueError, "mode must be 'r' or 'w'"
|
|
|
|
try:
|
|
import gzip
|
|
gzip.GzipFile
|
|
except (ImportError, AttributeError):
|
|
raise CompressionError, "gzip module is not available"
|
|
|
|
pre, ext = os.path.splitext(name)
|
|
pre = os.path.basename(pre)
|
|
if ext == ".tgz":
|
|
ext = ".tar"
|
|
if ext == ".gz":
|
|
ext = ""
|
|
tarname = pre + ext
|
|
|
|
if fileobj is None:
|
|
fileobj = file(name, mode + "b")
|
|
|
|
if mode != "r":
|
|
name = tarname
|
|
|
|
try:
|
|
t = cls.taropen(tarname, mode,
|
|
gzip.GzipFile(name, mode, compresslevel, fileobj)
|
|
)
|
|
except IOError:
|
|
raise ReadError, "not a gzip file"
|
|
t._extfileobj = False
|
|
return t
|
|
|
|
gzopen = classmethod(gzopen)
|
|
|
|
def bz2open(cls, name, mode="r", fileobj=None, compresslevel=9):
|
|
"""Open bzip2 compressed tar archive name for reading or writing.
|
|
Appending is not allowed.
|
|
"""
|
|
if len(mode) > 1 or mode not in "rw":
|
|
raise ValueError, "mode must be 'r' or 'w'."
|
|
|
|
try:
|
|
import bz2
|
|
except ImportError:
|
|
raise CompressionError, "bz2 module is not available"
|
|
|
|
pre, ext = os.path.splitext(name)
|
|
pre = os.path.basename(pre)
|
|
if ext == ".tbz2":
|
|
ext = ".tar"
|
|
if ext == ".bz2":
|
|
ext = ""
|
|
tarname = pre + ext
|
|
|
|
if fileobj is not None:
|
|
raise ValueError, "no support for external file objects"
|
|
|
|
try:
|
|
t = cls.taropen(tarname, mode, bz2.BZ2File(name, mode, compresslevel=compresslevel))
|
|
except IOError:
|
|
raise ReadError, "not a bzip2 file"
|
|
t._extfileobj = False
|
|
return t
|
|
|
|
bz2open = classmethod(bz2open)
|
|
|
|
# All *open() methods are registered here.
|
|
OPEN_METH = {
|
|
"tar": "taropen", # uncompressed tar
|
|
"gz": "gzopen", # gzip compressed tar
|
|
"bz2": "bz2open" # bzip2 compressed tar
|
|
}
|
|
|
|
#--------------------------------------------------------------------------
|
|
# The public methods which TarFile provides:
|
|
|
|
def close(self):
|
|
"""Close the TarFile. In write-mode, two finishing zero blocks are
|
|
appended to the archive.
|
|
"""
|
|
if self.closed:
|
|
return
|
|
|
|
if self._mode in "aw":
|
|
self.fileobj.write(NUL * (BLOCKSIZE * 2))
|
|
self.offset += (BLOCKSIZE * 2)
|
|
# fill up the end with zero-blocks
|
|
# (like option -b20 for tar does)
|
|
blocks, remainder = divmod(self.offset, RECORDSIZE)
|
|
if remainder > 0:
|
|
self.fileobj.write(NUL * (RECORDSIZE - remainder))
|
|
|
|
if not self._extfileobj:
|
|
self.fileobj.close()
|
|
self.closed = True
|
|
|
|
def getmember(self, name):
|
|
"""Return a TarInfo object for member `name'. If `name' can not be
|
|
found in the archive, KeyError is raised. If a member occurs more
|
|
than once in the archive, its last occurence is assumed to be the
|
|
most up-to-date version.
|
|
"""
|
|
tarinfo = self._getmember(name)
|
|
if tarinfo is None:
|
|
raise KeyError, "filename %r not found" % name
|
|
return tarinfo
|
|
|
|
def getmembers(self):
|
|
"""Return the members of the archive as a list of TarInfo objects. The
|
|
list has the same order as the members in the archive.
|
|
"""
|
|
self._check()
|
|
if not self._loaded: # if we want to obtain a list of
|
|
self._load() # all members, we first have to
|
|
# scan the whole archive.
|
|
return self.members
|
|
|
|
def getnames(self):
|
|
"""Return the members of the archive as a list of their names. It has
|
|
the same order as the list returned by getmembers().
|
|
"""
|
|
return [tarinfo.name for tarinfo in self.getmembers()]
|
|
|
|
def gettarinfo(self, name=None, arcname=None, fileobj=None):
|
|
"""Create a TarInfo object for either the file `name' or the file
|
|
object `fileobj' (using os.fstat on its file descriptor). You can
|
|
modify some of the TarInfo's attributes before you add it using
|
|
addfile(). If given, `arcname' specifies an alternative name for the
|
|
file in the archive.
|
|
"""
|
|
self._check("aw")
|
|
|
|
# When fileobj is given, replace name by
|
|
# fileobj's real name.
|
|
if fileobj is not None:
|
|
name = fileobj.name
|
|
|
|
# Building the name of the member in the archive.
|
|
# Backward slashes are converted to forward slashes,
|
|
# Absolute paths are turned to relative paths.
|
|
if arcname is None:
|
|
arcname = name
|
|
arcname = normpath(arcname)
|
|
drv, arcname = os.path.splitdrive(arcname)
|
|
while arcname[0:1] == "/":
|
|
arcname = arcname[1:]
|
|
|
|
# Now, fill the TarInfo object with
|
|
# information specific for the file.
|
|
tarinfo = TarInfo()
|
|
|
|
# Use os.stat or os.lstat, depending on platform
|
|
# and if symlinks shall be resolved.
|
|
if fileobj is None:
|
|
if hasattr(os, "lstat") and not self.dereference:
|
|
statres = os.lstat(name)
|
|
else:
|
|
statres = os.stat(name)
|
|
else:
|
|
statres = os.fstat(fileobj.fileno())
|
|
linkname = ""
|
|
|
|
stmd = statres.st_mode
|
|
if stat.S_ISREG(stmd):
|
|
inode = (statres.st_ino, statres.st_dev)
|
|
if inode in self.inodes and not self.dereference:
|
|
# Is it a hardlink to an already
|
|
# archived file?
|
|
type = LNKTYPE
|
|
linkname = self.inodes[inode]
|
|
else:
|
|
# The inode is added only if its valid.
|
|
# For win32 it is always 0.
|
|
type = REGTYPE
|
|
if inode[0]:
|
|
self.inodes[inode] = arcname
|
|
elif stat.S_ISDIR(stmd):
|
|
type = DIRTYPE
|
|
if arcname[-1:] != "/":
|
|
arcname += "/"
|
|
elif stat.S_ISFIFO(stmd):
|
|
type = FIFOTYPE
|
|
elif stat.S_ISLNK(stmd):
|
|
type = SYMTYPE
|
|
linkname = os.readlink(name)
|
|
elif stat.S_ISCHR(stmd):
|
|
type = CHRTYPE
|
|
elif stat.S_ISBLK(stmd):
|
|
type = BLKTYPE
|
|
else:
|
|
return None
|
|
|
|
# Fill the TarInfo object with all
|
|
# information we can get.
|
|
tarinfo.name = arcname
|
|
tarinfo.mode = stmd
|
|
tarinfo.uid = statres.st_uid
|
|
tarinfo.gid = statres.st_gid
|
|
if stat.S_ISDIR(stmd):
|
|
# For a directory, the size must be 0
|
|
tarinfo.size = 0
|
|
else:
|
|
tarinfo.size = statres.st_size
|
|
tarinfo.mtime = statres.st_mtime
|
|
tarinfo.type = type
|
|
tarinfo.linkname = linkname
|
|
if pwd:
|
|
try:
|
|
tarinfo.uname = pwd.getpwuid(tarinfo.uid)[0]
|
|
except KeyError:
|
|
pass
|
|
if grp:
|
|
try:
|
|
tarinfo.gname = grp.getgrgid(tarinfo.gid)[0]
|
|
except KeyError:
|
|
pass
|
|
|
|
if type in (CHRTYPE, BLKTYPE):
|
|
if hasattr(os, "major") and hasattr(os, "minor"):
|
|
tarinfo.devmajor = os.major(statres.st_rdev)
|
|
tarinfo.devminor = os.minor(statres.st_rdev)
|
|
return tarinfo
|
|
|
|
def list(self, verbose=True):
|
|
"""Print a table of contents to sys.stdout. If `verbose' is False, only
|
|
the names of the members are printed. If it is True, an `ls -l'-like
|
|
output is produced.
|
|
"""
|
|
self._check()
|
|
|
|
for tarinfo in self:
|
|
if verbose:
|
|
print filemode(tarinfo.mode),
|
|
print "%s/%s" % (tarinfo.uname or tarinfo.uid,
|
|
tarinfo.gname or tarinfo.gid),
|
|
if tarinfo.ischr() or tarinfo.isblk():
|
|
print "%10s" % ("%d,%d" \
|
|
% (tarinfo.devmajor, tarinfo.devminor)),
|
|
else:
|
|
print "%10d" % tarinfo.size,
|
|
print "%d-%02d-%02d %02d:%02d:%02d" \
|
|
% time.localtime(tarinfo.mtime)[:6],
|
|
|
|
print tarinfo.name,
|
|
|
|
if verbose:
|
|
if tarinfo.issym():
|
|
print "->", tarinfo.linkname,
|
|
if tarinfo.islnk():
|
|
print "link to", tarinfo.linkname,
|
|
print
|
|
|
|
def add(self, name, arcname=None, recursive=True):
|
|
"""Add the file `name' to the archive. `name' may be any type of file
|
|
(directory, fifo, symbolic link, etc.). If given, `arcname'
|
|
specifies an alternative name for the file in the archive.
|
|
Directories are added recursively by default. This can be avoided by
|
|
setting `recursive' to False.
|
|
"""
|
|
self._check("aw")
|
|
|
|
if arcname is None:
|
|
arcname = name
|
|
|
|
# Skip if somebody tries to archive the archive...
|
|
if self.name is not None \
|
|
and os.path.abspath(name) == os.path.abspath(self.name):
|
|
self._dbg(2, "tarfile: Skipped %r" % name)
|
|
return
|
|
|
|
# Special case: The user wants to add the current
|
|
# working directory.
|
|
if name == ".":
|
|
if recursive:
|
|
if arcname == ".":
|
|
arcname = ""
|
|
for f in os.listdir("."):
|
|
self.add(f, os.path.join(arcname, f))
|
|
return
|
|
|
|
self._dbg(1, name)
|
|
|
|
# Create a TarInfo object from the file.
|
|
tarinfo = self.gettarinfo(name, arcname)
|
|
|
|
if tarinfo is None:
|
|
self._dbg(1, "tarfile: Unsupported type %r" % name)
|
|
return
|
|
|
|
# Append the tar header and data to the archive.
|
|
if tarinfo.isreg():
|
|
f = file(name, "rb")
|
|
self.addfile(tarinfo, f)
|
|
f.close()
|
|
|
|
if tarinfo.type in (LNKTYPE, SYMTYPE, FIFOTYPE, CHRTYPE, BLKTYPE):
|
|
tarinfo.size = 0L
|
|
self.addfile(tarinfo)
|
|
|
|
if tarinfo.isdir():
|
|
self.addfile(tarinfo)
|
|
if recursive:
|
|
for f in os.listdir(name):
|
|
self.add(os.path.join(name, f), os.path.join(arcname, f))
|
|
|
|
def addfile(self, tarinfo, fileobj=None):
|
|
"""Add the TarInfo object `tarinfo' to the archive. If `fileobj' is
|
|
given, tarinfo.size bytes are read from it and added to the archive.
|
|
You can create TarInfo objects using gettarinfo().
|
|
On Windows platforms, `fileobj' should always be opened with mode
|
|
'rb' to avoid irritation about the file size.
|
|
"""
|
|
self._check("aw")
|
|
|
|
tarinfo.name = normpath(tarinfo.name)
|
|
if tarinfo.isdir():
|
|
# directories should end with '/'
|
|
tarinfo.name += "/"
|
|
|
|
if tarinfo.linkname:
|
|
tarinfo.linkname = normpath(tarinfo.linkname)
|
|
|
|
if tarinfo.size > MAXSIZE_MEMBER:
|
|
if self.posix:
|
|
raise ValueError, "file is too large (>= 8 GB)"
|
|
else:
|
|
self._dbg(2, "tarfile: Created GNU tar largefile header")
|
|
|
|
|
|
if len(tarinfo.linkname) > LENGTH_LINK:
|
|
if self.posix:
|
|
raise ValueError, "linkname is too long (>%d)" \
|
|
% (LENGTH_LINK)
|
|
else:
|
|
self._create_gnulong(tarinfo.linkname, GNUTYPE_LONGLINK)
|
|
tarinfo.linkname = tarinfo.linkname[:LENGTH_LINK -1]
|
|
self._dbg(2, "tarfile: Created GNU tar extension LONGLINK")
|
|
|
|
if len(tarinfo.name) > LENGTH_NAME:
|
|
if self.posix:
|
|
prefix = tarinfo.name[:LENGTH_PREFIX + 1]
|
|
while prefix and prefix[-1] != "/":
|
|
prefix = prefix[:-1]
|
|
|
|
name = tarinfo.name[len(prefix):]
|
|
prefix = prefix[:-1]
|
|
|
|
if not prefix or len(name) > LENGTH_NAME:
|
|
raise ValueError, "name is too long (>%d)" \
|
|
% (LENGTH_NAME)
|
|
|
|
tarinfo.name = name
|
|
tarinfo.prefix = prefix
|
|
else:
|
|
self._create_gnulong(tarinfo.name, GNUTYPE_LONGNAME)
|
|
tarinfo.name = tarinfo.name[:LENGTH_NAME - 1]
|
|
self._dbg(2, "tarfile: Created GNU tar extension LONGNAME")
|
|
|
|
self.fileobj.write(tarinfo.tobuf())
|
|
self.offset += BLOCKSIZE
|
|
|
|
# If there's data to follow, append it.
|
|
if fileobj is not None:
|
|
copyfileobj(fileobj, self.fileobj, tarinfo.size)
|
|
blocks, remainder = divmod(tarinfo.size, BLOCKSIZE)
|
|
if remainder > 0:
|
|
self.fileobj.write(NUL * (BLOCKSIZE - remainder))
|
|
blocks += 1
|
|
self.offset += blocks * BLOCKSIZE
|
|
|
|
self.members.append(tarinfo)
|
|
|
|
def extract(self, member, path=""):
|
|
"""Extract a member from the archive to the current working directory,
|
|
using its full name. Its file information is extracted as accurately
|
|
as possible. `member' may be a filename or a TarInfo object. You can
|
|
specify a different directory using `path'.
|
|
"""
|
|
self._check("r")
|
|
|
|
if isinstance(member, TarInfo):
|
|
tarinfo = member
|
|
else:
|
|
tarinfo = self.getmember(member)
|
|
|
|
# Prepare the link target for makelink().
|
|
if tarinfo.islnk():
|
|
tarinfo._link_target = os.path.join(path, tarinfo.linkname)
|
|
|
|
try:
|
|
self._extract_member(tarinfo, os.path.join(path, tarinfo.name))
|
|
except EnvironmentError, e:
|
|
if self.errorlevel > 0:
|
|
raise
|
|
else:
|
|
if e.filename is None:
|
|
self._dbg(1, "tarfile: %s" % e.strerror)
|
|
else:
|
|
self._dbg(1, "tarfile: %s %r" % (e.strerror, e.filename))
|
|
except ExtractError, e:
|
|
if self.errorlevel > 1:
|
|
raise
|
|
else:
|
|
self._dbg(1, "tarfile: %s" % e)
|
|
|
|
def extractfile(self, member):
|
|
"""Extract a member from the archive as a file object. `member' may be
|
|
a filename or a TarInfo object. If `member' is a regular file, a
|
|
file-like object is returned. If `member' is a link, a file-like
|
|
object is constructed from the link's target. If `member' is none of
|
|
the above, None is returned.
|
|
The file-like object is read-only and provides the following
|
|
methods: read(), readline(), readlines(), seek() and tell()
|
|
"""
|
|
self._check("r")
|
|
|
|
if isinstance(member, TarInfo):
|
|
tarinfo = member
|
|
else:
|
|
tarinfo = self.getmember(member)
|
|
|
|
if tarinfo.isreg():
|
|
return self.fileobject(self, tarinfo)
|
|
|
|
elif tarinfo.type not in SUPPORTED_TYPES:
|
|
# If a member's type is unknown, it is treated as a
|
|
# regular file.
|
|
return self.fileobject(self, tarinfo)
|
|
|
|
elif tarinfo.islnk() or tarinfo.issym():
|
|
if isinstance(self.fileobj, _Stream):
|
|
# A small but ugly workaround for the case that someone tries
|
|
# to extract a (sym)link as a file-object from a non-seekable
|
|
# stream of tar blocks.
|
|
raise StreamError, "cannot extract (sym)link as file object"
|
|
else:
|
|
# A (sym)link's file object is it's target's file object.
|
|
return self.extractfile(self._getmember(tarinfo.linkname,
|
|
tarinfo))
|
|
else:
|
|
# If there's no data associated with the member (directory, chrdev,
|
|
# blkdev, etc.), return None instead of a file object.
|
|
return None
|
|
|
|
def _extract_member(self, tarinfo, targetpath):
|
|
"""Extract the TarInfo object tarinfo to a physical
|
|
file called targetpath.
|
|
"""
|
|
# Fetch the TarInfo object for the given name
|
|
# and build the destination pathname, replacing
|
|
# forward slashes to platform specific separators.
|
|
if targetpath[-1:] == "/":
|
|
targetpath = targetpath[:-1]
|
|
targetpath = os.path.normpath(targetpath)
|
|
|
|
# Create all upper directories.
|
|
upperdirs = os.path.dirname(targetpath)
|
|
if upperdirs and not os.path.exists(upperdirs):
|
|
ti = TarInfo()
|
|
ti.name = upperdirs
|
|
ti.type = DIRTYPE
|
|
ti.mode = 0777
|
|
ti.mtime = tarinfo.mtime
|
|
ti.uid = tarinfo.uid
|
|
ti.gid = tarinfo.gid
|
|
ti.uname = tarinfo.uname
|
|
ti.gname = tarinfo.gname
|
|
try:
|
|
self._extract_member(ti, ti.name)
|
|
except:
|
|
pass
|
|
|
|
if tarinfo.islnk() or tarinfo.issym():
|
|
self._dbg(1, "%s -> %s" % (tarinfo.name, tarinfo.linkname))
|
|
else:
|
|
self._dbg(1, tarinfo.name)
|
|
|
|
if tarinfo.isreg():
|
|
self.makefile(tarinfo, targetpath)
|
|
elif tarinfo.isdir():
|
|
self.makedir(tarinfo, targetpath)
|
|
elif tarinfo.isfifo():
|
|
self.makefifo(tarinfo, targetpath)
|
|
elif tarinfo.ischr() or tarinfo.isblk():
|
|
self.makedev(tarinfo, targetpath)
|
|
elif tarinfo.islnk() or tarinfo.issym():
|
|
self.makelink(tarinfo, targetpath)
|
|
elif tarinfo.type not in SUPPORTED_TYPES:
|
|
self.makeunknown(tarinfo, targetpath)
|
|
else:
|
|
self.makefile(tarinfo, targetpath)
|
|
|
|
self.chown(tarinfo, targetpath)
|
|
if not tarinfo.issym():
|
|
self.chmod(tarinfo, targetpath)
|
|
self.utime(tarinfo, targetpath)
|
|
|
|
#--------------------------------------------------------------------------
|
|
# Below are the different file methods. They are called via
|
|
# _extract_member() when extract() is called. They can be replaced in a
|
|
# subclass to implement other functionality.
|
|
|
|
def makedir(self, tarinfo, targetpath):
|
|
"""Make a directory called targetpath.
|
|
"""
|
|
try:
|
|
os.mkdir(targetpath)
|
|
except EnvironmentError, e:
|
|
if e.errno != errno.EEXIST:
|
|
raise
|
|
|
|
def makefile(self, tarinfo, targetpath):
|
|
"""Make a file called targetpath.
|
|
"""
|
|
source = self.extractfile(tarinfo)
|
|
target = file(targetpath, "wb")
|
|
copyfileobj(source, target)
|
|
source.close()
|
|
target.close()
|
|
|
|
def makeunknown(self, tarinfo, targetpath):
|
|
"""Make a file from a TarInfo object with an unknown type
|
|
at targetpath.
|
|
"""
|
|
self.makefile(tarinfo, targetpath)
|
|
self._dbg(1, "tarfile: Unknown file type %r, " \
|
|
"extracted as regular file." % tarinfo.type)
|
|
|
|
def makefifo(self, tarinfo, targetpath):
|
|
"""Make a fifo called targetpath.
|
|
"""
|
|
if hasattr(os, "mkfifo"):
|
|
os.mkfifo(targetpath)
|
|
else:
|
|
raise ExtractError, "fifo not supported by system"
|
|
|
|
def makedev(self, tarinfo, targetpath):
|
|
"""Make a character or block device called targetpath.
|
|
"""
|
|
if not hasattr(os, "mknod") or not hasattr(os, "makedev"):
|
|
raise ExtractError, "special devices not supported by system"
|
|
|
|
mode = tarinfo.mode
|
|
if tarinfo.isblk():
|
|
mode |= stat.S_IFBLK
|
|
else:
|
|
mode |= stat.S_IFCHR
|
|
|
|
os.mknod(targetpath, mode,
|
|
os.makedev(tarinfo.devmajor, tarinfo.devminor))
|
|
|
|
def makelink(self, tarinfo, targetpath):
|
|
"""Make a (symbolic) link called targetpath. If it cannot be created
|
|
(platform limitation), we try to make a copy of the referenced file
|
|
instead of a link.
|
|
"""
|
|
linkpath = tarinfo.linkname
|
|
try:
|
|
if tarinfo.issym():
|
|
os.symlink(linkpath, targetpath)
|
|
else:
|
|
# See extract().
|
|
os.link(tarinfo._link_target, targetpath)
|
|
except AttributeError:
|
|
if tarinfo.issym():
|
|
linkpath = os.path.join(os.path.dirname(tarinfo.name),
|
|
linkpath)
|
|
linkpath = normpath(linkpath)
|
|
|
|
try:
|
|
self._extract_member(self.getmember(linkpath), targetpath)
|
|
except (EnvironmentError, KeyError), e:
|
|
linkpath = os.path.normpath(linkpath)
|
|
try:
|
|
shutil.copy2(linkpath, targetpath)
|
|
except EnvironmentError, e:
|
|
raise IOError, "link could not be created"
|
|
|
|
def chown(self, tarinfo, targetpath):
|
|
"""Set owner of targetpath according to tarinfo.
|
|
"""
|
|
if pwd and hasattr(os, "geteuid") and os.geteuid() == 0:
|
|
# We have to be root to do so.
|
|
try:
|
|
g = grp.getgrnam(tarinfo.gname)[2]
|
|
except KeyError:
|
|
try:
|
|
g = grp.getgrgid(tarinfo.gid)[2]
|
|
except KeyError:
|
|
g = os.getgid()
|
|
try:
|
|
u = pwd.getpwnam(tarinfo.uname)[2]
|
|
except KeyError:
|
|
try:
|
|
u = pwd.getpwuid(tarinfo.uid)[2]
|
|
except KeyError:
|
|
u = os.getuid()
|
|
try:
|
|
if tarinfo.issym() and hasattr(os, "lchown"):
|
|
os.lchown(targetpath, u, g)
|
|
else:
|
|
if sys.platform != "os2emx":
|
|
os.chown(targetpath, u, g)
|
|
except EnvironmentError, e:
|
|
raise ExtractError, "could not change owner"
|
|
|
|
def chmod(self, tarinfo, targetpath):
|
|
"""Set file permissions of targetpath according to tarinfo.
|
|
"""
|
|
if hasattr(os, 'chmod'):
|
|
try:
|
|
os.chmod(targetpath, tarinfo.mode)
|
|
except EnvironmentError, e:
|
|
raise ExtractError, "could not change mode"
|
|
|
|
def utime(self, tarinfo, targetpath):
|
|
"""Set modification time of targetpath according to tarinfo.
|
|
"""
|
|
if not hasattr(os, 'utime'):
|
|
return
|
|
if sys.platform == "win32" and tarinfo.isdir():
|
|
# According to msdn.microsoft.com, it is an error (EACCES)
|
|
# to use utime() on directories.
|
|
return
|
|
try:
|
|
os.utime(targetpath, (tarinfo.mtime, tarinfo.mtime))
|
|
except EnvironmentError, e:
|
|
raise ExtractError, "could not change modification time"
|
|
|
|
#--------------------------------------------------------------------------
|
|
|
|
def next(self):
|
|
"""Return the next member of the archive as a TarInfo object, when
|
|
TarFile is opened for reading. Return None if there is no more
|
|
available.
|
|
"""
|
|
self._check("ra")
|
|
if self.firstmember is not None:
|
|
m = self.firstmember
|
|
self.firstmember = None
|
|
return m
|
|
|
|
# Read the next block.
|
|
self.fileobj.seek(self.offset)
|
|
while True:
|
|
buf = self.fileobj.read(BLOCKSIZE)
|
|
if not buf:
|
|
return None
|
|
try:
|
|
tarinfo = TarInfo.frombuf(buf)
|
|
except ValueError:
|
|
if self.ignore_zeros:
|
|
if buf.count(NUL) == BLOCKSIZE:
|
|
adj = "empty"
|
|
else:
|
|
adj = "invalid"
|
|
self._dbg(2, "0x%X: %s block" % (self.offset, adj))
|
|
self.offset += BLOCKSIZE
|
|
continue
|
|
else:
|
|
# Block is empty or unreadable.
|
|
if self.offset == 0:
|
|
# If the first block is invalid. That does not
|
|
# look like a tar archive we can handle.
|
|
raise ReadError,"empty, unreadable or compressed file"
|
|
return None
|
|
break
|
|
|
|
# We shouldn't rely on this checksum, because some tar programs
|
|
# calculate it differently and it is merely validating the
|
|
# header block. We could just as well skip this part, which would
|
|
# have a slight effect on performance...
|
|
if tarinfo.chksum != calc_chksum(buf):
|
|
self._dbg(1, "tarfile: Bad Checksum %r" % tarinfo.name)
|
|
|
|
# Set the TarInfo object's offset to the current position of the
|
|
# TarFile and set self.offset to the position where the data blocks
|
|
# should begin.
|
|
tarinfo.offset = self.offset
|
|
self.offset += BLOCKSIZE
|
|
|
|
# Check if the TarInfo object has a typeflag for which a callback
|
|
# method is registered in the TYPE_METH. If so, then call it.
|
|
if tarinfo.type in self.TYPE_METH:
|
|
return self.TYPE_METH[tarinfo.type](self, tarinfo)
|
|
|
|
tarinfo.offset_data = self.offset
|
|
if tarinfo.isreg() or tarinfo.type not in SUPPORTED_TYPES:
|
|
# Skip the following data blocks.
|
|
self.offset += self._block(tarinfo.size)
|
|
|
|
if tarinfo.isreg() and tarinfo.name[:-1] == "/":
|
|
# some old tar programs don't know DIRTYPE
|
|
tarinfo.type = DIRTYPE
|
|
|
|
self.members.append(tarinfo)
|
|
return tarinfo
|
|
|
|
#--------------------------------------------------------------------------
|
|
# Below are some methods which are called for special typeflags in the
|
|
# next() method, e.g. for unwrapping GNU longname/longlink blocks. They
|
|
# are registered in TYPE_METH below. You can register your own methods
|
|
# with this mapping.
|
|
# A registered method is called with a TarInfo object as only argument.
|
|
#
|
|
# During its execution the method MUST perform the following tasks:
|
|
# 1. set tarinfo.offset_data to the position where the data blocks begin,
|
|
# if there is data to follow.
|
|
# 2. set self.offset to the position where the next member's header will
|
|
# begin.
|
|
# 3. append the tarinfo object to self.members, if it is supposed to appear
|
|
# as a member of the TarFile object.
|
|
# 4. return tarinfo or another valid TarInfo object.
|
|
|
|
def proc_gnulong(self, tarinfo):
|
|
"""Evaluate the blocks that hold a GNU longname
|
|
or longlink member.
|
|
"""
|
|
buf = ""
|
|
count = tarinfo.size
|
|
while count > 0:
|
|
block = self.fileobj.read(BLOCKSIZE)
|
|
buf += block
|
|
self.offset += BLOCKSIZE
|
|
count -= BLOCKSIZE
|
|
|
|
# Fetch the next header
|
|
next = self.next()
|
|
|
|
next.offset = tarinfo.offset
|
|
if tarinfo.type == GNUTYPE_LONGNAME:
|
|
next.name = nts(buf)
|
|
elif tarinfo.type == GNUTYPE_LONGLINK:
|
|
next.linkname = nts(buf)
|
|
|
|
return next
|
|
|
|
def proc_sparse(self, tarinfo):
|
|
"""Analyze a GNU sparse header plus extra headers.
|
|
"""
|
|
buf = tarinfo.tobuf()
|
|
sp = _ringbuffer()
|
|
pos = 386
|
|
lastpos = 0L
|
|
realpos = 0L
|
|
# There are 4 possible sparse structs in the
|
|
# first header.
|
|
for i in xrange(4):
|
|
try:
|
|
offset = int(buf[pos:pos + 12], 8)
|
|
numbytes = int(buf[pos + 12:pos + 24], 8)
|
|
except ValueError:
|
|
break
|
|
if offset > lastpos:
|
|
sp.append(_hole(lastpos, offset - lastpos))
|
|
sp.append(_data(offset, numbytes, realpos))
|
|
realpos += numbytes
|
|
lastpos = offset + numbytes
|
|
pos += 24
|
|
|
|
isextended = ord(buf[482])
|
|
origsize = int(buf[483:495], 8)
|
|
|
|
# If the isextended flag is given,
|
|
# there are extra headers to process.
|
|
while isextended == 1:
|
|
buf = self.fileobj.read(BLOCKSIZE)
|
|
self.offset += BLOCKSIZE
|
|
pos = 0
|
|
for i in xrange(21):
|
|
try:
|
|
offset = int(buf[pos:pos + 12], 8)
|
|
numbytes = int(buf[pos + 12:pos + 24], 8)
|
|
except ValueError:
|
|
break
|
|
if offset > lastpos:
|
|
sp.append(_hole(lastpos, offset - lastpos))
|
|
sp.append(_data(offset, numbytes, realpos))
|
|
realpos += numbytes
|
|
lastpos = offset + numbytes
|
|
pos += 24
|
|
isextended = ord(buf[504])
|
|
|
|
if lastpos < origsize:
|
|
sp.append(_hole(lastpos, origsize - lastpos))
|
|
|
|
tarinfo.sparse = sp
|
|
|
|
tarinfo.offset_data = self.offset
|
|
self.offset += self._block(tarinfo.size)
|
|
tarinfo.size = origsize
|
|
|
|
self.members.append(tarinfo)
|
|
return tarinfo
|
|
|
|
# The type mapping for the next() method. The keys are single character
|
|
# strings, the typeflag. The values are methods which are called when
|
|
# next() encounters such a typeflag.
|
|
TYPE_METH = {
|
|
GNUTYPE_LONGNAME: proc_gnulong,
|
|
GNUTYPE_LONGLINK: proc_gnulong,
|
|
GNUTYPE_SPARSE: proc_sparse
|
|
}
|
|
|
|
#--------------------------------------------------------------------------
|
|
# Little helper methods:
|
|
|
|
def _block(self, count):
|
|
"""Round up a byte count by BLOCKSIZE and return it,
|
|
e.g. _block(834) => 1024.
|
|
"""
|
|
blocks, remainder = divmod(count, BLOCKSIZE)
|
|
if remainder:
|
|
blocks += 1
|
|
return blocks * BLOCKSIZE
|
|
|
|
def _getmember(self, name, tarinfo=None):
|
|
"""Find an archive member by name from bottom to top.
|
|
If tarinfo is given, it is used as the starting point.
|
|
"""
|
|
# Ensure that all members have been loaded.
|
|
members = self.getmembers()
|
|
|
|
if tarinfo is None:
|
|
end = len(members)
|
|
else:
|
|
end = members.index(tarinfo)
|
|
|
|
for i in xrange(end - 1, -1, -1):
|
|
if name == members[i].name:
|
|
return members[i]
|
|
|
|
def _load(self):
|
|
"""Read through the entire archive file and look for readable
|
|
members.
|
|
"""
|
|
while True:
|
|
tarinfo = self.next()
|
|
if tarinfo is None:
|
|
break
|
|
self._loaded = True
|
|
|
|
def _check(self, mode=None):
|
|
"""Check if TarFile is still open, and if the operation's mode
|
|
corresponds to TarFile's mode.
|
|
"""
|
|
if self.closed:
|
|
raise IOError, "%s is closed" % self.__class__.__name__
|
|
if mode is not None and self._mode not in mode:
|
|
raise IOError, "bad operation for mode %r" % self._mode
|
|
|
|
def __iter__(self):
|
|
"""Provide an iterator object.
|
|
"""
|
|
if self._loaded:
|
|
return iter(self.members)
|
|
else:
|
|
return TarIter(self)
|
|
|
|
def _create_gnulong(self, name, type):
|
|
"""Write a GNU longname/longlink member to the TarFile.
|
|
It consists of an extended tar header, with the length
|
|
of the longname as size, followed by data blocks,
|
|
which contain the longname as a null terminated string.
|
|
"""
|
|
name += NUL
|
|
|
|
tarinfo = TarInfo()
|
|
tarinfo.name = "././@LongLink"
|
|
tarinfo.type = type
|
|
tarinfo.mode = 0
|
|
tarinfo.size = len(name)
|
|
|
|
# write extended header
|
|
self.fileobj.write(tarinfo.tobuf())
|
|
self.offset += BLOCKSIZE
|
|
# write name blocks
|
|
self.fileobj.write(name)
|
|
blocks, remainder = divmod(tarinfo.size, BLOCKSIZE)
|
|
if remainder > 0:
|
|
self.fileobj.write(NUL * (BLOCKSIZE - remainder))
|
|
blocks += 1
|
|
self.offset += blocks * BLOCKSIZE
|
|
|
|
def _dbg(self, level, msg):
|
|
"""Write debugging output to sys.stderr.
|
|
"""
|
|
if level <= self.debug:
|
|
print >> sys.stderr, msg
|
|
# class TarFile
|
|
|
|
class TarIter:
|
|
"""Iterator Class.
|
|
|
|
for tarinfo in TarFile(...):
|
|
suite...
|
|
"""
|
|
|
|
def __init__(self, tarfile):
|
|
"""Construct a TarIter object.
|
|
"""
|
|
self.tarfile = tarfile
|
|
def __iter__(self):
|
|
"""Return iterator object.
|
|
"""
|
|
return self
|
|
def next(self):
|
|
"""Return the next item using TarFile's next() method.
|
|
When all members have been read, set TarFile as _loaded.
|
|
"""
|
|
tarinfo = self.tarfile.next()
|
|
if not tarinfo:
|
|
self.tarfile._loaded = True
|
|
raise StopIteration
|
|
return tarinfo
|
|
|
|
# Helper classes for sparse file support
|
|
class _section:
|
|
"""Base class for _data and _hole.
|
|
"""
|
|
def __init__(self, offset, size):
|
|
self.offset = offset
|
|
self.size = size
|
|
def __contains__(self, offset):
|
|
return self.offset <= offset < self.offset + self.size
|
|
|
|
class _data(_section):
|
|
"""Represent a data section in a sparse file.
|
|
"""
|
|
def __init__(self, offset, size, realpos):
|
|
_section.__init__(self, offset, size)
|
|
self.realpos = realpos
|
|
|
|
class _hole(_section):
|
|
"""Represent a hole section in a sparse file.
|
|
"""
|
|
pass
|
|
|
|
class _ringbuffer(list):
|
|
"""Ringbuffer class which increases performance
|
|
over a regular list.
|
|
"""
|
|
def __init__(self):
|
|
self.idx = 0
|
|
def find(self, offset):
|
|
idx = self.idx
|
|
while True:
|
|
item = self[idx]
|
|
if offset in item:
|
|
break
|
|
idx += 1
|
|
if idx == len(self):
|
|
idx = 0
|
|
if idx == self.idx:
|
|
# End of File
|
|
return None
|
|
self.idx = idx
|
|
return item
|
|
|
|
#---------------------------------------------
|
|
# zipfile compatible TarFile class
|
|
#---------------------------------------------
|
|
TAR_PLAIN = 0 # zipfile.ZIP_STORED
|
|
TAR_GZIPPED = 8 # zipfile.ZIP_DEFLATED
|
|
class TarFileCompat:
|
|
"""TarFile class compatible with standard module zipfile's
|
|
ZipFile class.
|
|
"""
|
|
def __init__(self, file, mode="r", compression=TAR_PLAIN):
|
|
if compression == TAR_PLAIN:
|
|
self.tarfile = TarFile.taropen(file, mode)
|
|
elif compression == TAR_GZIPPED:
|
|
self.tarfile = TarFile.gzopen(file, mode)
|
|
else:
|
|
raise ValueError, "unknown compression constant"
|
|
if mode[0:1] == "r":
|
|
members = self.tarfile.getmembers()
|
|
for i in xrange(len(members)):
|
|
m = members[i]
|
|
m.filename = m.name
|
|
m.file_size = m.size
|
|
m.date_time = time.gmtime(m.mtime)[:6]
|
|
def namelist(self):
|
|
return map(lambda m: m.name, self.infolist())
|
|
def infolist(self):
|
|
return filter(lambda m: m.type in REGULAR_TYPES,
|
|
self.tarfile.getmembers())
|
|
def printdir(self):
|
|
self.tarfile.list()
|
|
def testzip(self):
|
|
return
|
|
def getinfo(self, name):
|
|
return self.tarfile.getmember(name)
|
|
def read(self, name):
|
|
return self.tarfile.extractfile(self.tarfile.getmember(name)).read()
|
|
def write(self, filename, arcname=None, compress_type=None):
|
|
self.tarfile.add(filename, arcname)
|
|
def writestr(self, zinfo, bytes):
|
|
try:
|
|
from cStringIO import StringIO
|
|
except ImportError:
|
|
from StringIO import StringIO
|
|
import calendar
|
|
zinfo.name = zinfo.filename
|
|
zinfo.size = zinfo.file_size
|
|
zinfo.mtime = calendar.timegm(zinfo.date_time)
|
|
self.tarfile.addfile(zinfo, StringIO(bytes))
|
|
def close(self):
|
|
self.tarfile.close()
|
|
#class TarFileCompat
|
|
|
|
#--------------------
|
|
# exported functions
|
|
#--------------------
|
|
def is_tarfile(name):
|
|
"""Return True if name points to a tar archive that we
|
|
are able to handle, else return False.
|
|
"""
|
|
try:
|
|
t = open(name)
|
|
t.close()
|
|
return True
|
|
except TarError:
|
|
return False
|
|
|
|
open = TarFile.open
|