From 74d838697fc2fd3d11d2885891950fe2122d70e9 Mon Sep 17 00:00:00 2001 From: Jake Moshenko Date: Fri, 7 Aug 2015 11:56:38 -0400 Subject: [PATCH] Fix tarfile to support non-unicode pax fields --- test/data/sample/layers/paxheader.tar | Bin 0 -> 2560 bytes test/test_changes.py | 7 + util/registry/changes.py | 4 +- util/vendor/__init__.py | 0 util/vendor/paxtarfile.py | 2641 +++++++++++++++++++++++++ 5 files changed, 2651 insertions(+), 1 deletion(-) create mode 100644 test/data/sample/layers/paxheader.tar create mode 100644 util/vendor/__init__.py create mode 100644 util/vendor/paxtarfile.py diff --git a/test/data/sample/layers/paxheader.tar b/test/data/sample/layers/paxheader.tar new file mode 100644 index 0000000000000000000000000000000000000000..819351d42f41430bf402b3c672b571e3eaf8b095 GIT binary patch literal 2560 zcmWGYtnf%pOi3*&)-yCRu(Z@q%gjk-pe`_g00tbifq}UpgQ1bJv8joPiJ_SpgMp!u zxuGe8LIri5f!(yy;*!K7pwqC+5-*DGIpTE=s7h0FgVE5xzPBd+@To)G|2840byWhU|?oqf;;~Mb02E{2kHRk de~R-YhD)#rjPU%AB}7JrMnhmU1V%^*0091(G-Ch& literal 0 HcmV?d00001 diff --git a/test/test_changes.py b/test/test_changes.py index b4ae716fa..ca0b4f0d2 100644 --- a/test/test_changes.py +++ b/test/test_changes.py @@ -62,5 +62,12 @@ class TestChanges(unittest.TestCase): self.assertIn('another_file', deleted_prefixes) + def test_pax_tarfile_error(self): + # If this fails it will raise an exception + with open('test/data/sample/layers/paxheader.tar') as tarstream: + result = list(files_and_dirs_from_tar(tarstream, set())) + + self.assertIn('/file', result) + if __name__ == '__main__': unittest.main() \ No newline at end of file diff --git a/util/registry/changes.py b/util/registry/changes.py index 9ffb3bddc..0e7f31c80 100644 --- a/util/registry/changes.py +++ b/util/registry/changes.py @@ -1,6 +1,8 @@ import marisa_trie import os -import tarfile + +import util.vendor.paxtarfile as tarfile + from util.registry.aufs import is_aufs_metadata, get_deleted_prefix ALLOWED_TYPES = {tarfile.REGTYPE, tarfile.AREGTYPE} diff --git a/util/vendor/__init__.py b/util/vendor/__init__.py new file mode 100644 index 000000000..e69de29bb diff --git a/util/vendor/paxtarfile.py b/util/vendor/paxtarfile.py new file mode 100644 index 000000000..ade0bdc37 --- /dev/null +++ b/util/vendor/paxtarfile.py @@ -0,0 +1,2641 @@ +# -*- coding: iso-8859-1 -*- + +# This version of tarfile was taken from python 2.7.10, and amended +# to fix a problem trying to decode non-text header fields present +# in some tar files using pax headers and/or extended attributes. + +#------------------------------------------------------------------- +# tarfile.py +#------------------------------------------------------------------- +# Copyright (C) 2002 Lars Gustäbel +# 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: 85213 $" +# $Source$ + +version = "0.9.0" +__author__ = "Lars Gustäbel (lars@gustaebel.de)" +__date__ = "$Date$" +__cvsid__ = "$Id$" +__credits__ = "Gustavo Niemeyer, Niels Gustäbel, Richard Townsend." + +#--------- +# Imports +#--------- +from __builtin__ import open as bltn_open +import sys +import os +import shutil +import stat +import errno +import time +import struct +import copy +import re +import operator + +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 +GNU_MAGIC = "ustar \0" # magic gnu tar string +POSIX_MAGIC = "ustar\x0000" # magic posix tar string + +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 + +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 longname +GNUTYPE_LONGLINK = "K" # GNU tar longlink +GNUTYPE_SPARSE = "S" # GNU tar sparse file + +XHDTYPE = "x" # POSIX.1-2001 extended header +XGLTYPE = "g" # POSIX.1-2001 global header +SOLARIS_XHDTYPE = "X" # Solaris extended header + +USTAR_FORMAT = 0 # POSIX.1-1988 (ustar) format +GNU_FORMAT = 1 # GNU tar format +PAX_FORMAT = 2 # POSIX.1-2001 (pax) format +DEFAULT_FORMAT = GNU_FORMAT + +#--------------------------------------------------------- +# tarfile constants +#--------------------------------------------------------- +# File types that tarfile supports: +SUPPORTED_TYPES = (REGTYPE, AREGTYPE, LNKTYPE, + SYMTYPE, DIRTYPE, FIFOTYPE, + CONTTYPE, CHRTYPE, BLKTYPE, + GNUTYPE_LONGNAME, GNUTYPE_LONGLINK, + GNUTYPE_SPARSE) + +# File types that will be treated as a regular file. +REGULAR_TYPES = (REGTYPE, AREGTYPE, + CONTTYPE, GNUTYPE_SPARSE) + +# File types that are part of the GNU tar format. +GNU_TYPES = (GNUTYPE_LONGNAME, GNUTYPE_LONGLINK, + GNUTYPE_SPARSE) + +# Fields from a pax header that override a TarInfo attribute. +PAX_FIELDS = ("path", "linkpath", "size", "mtime", + "uid", "gid", "uname", "gname", + "SCHILY.xattr.") + +# Fields in a pax header that are numbers, all other fields +# are treated as strings. +PAX_NUMBER_FIELDS = { + "atime": float, + "ctime": float, + "mtime": float, + "uid": int, + "gid": int, + "size": int, + "SCHILY.xattr.": dict, +} + +#--------------------------------------------------------- +# 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 + +#--------------------------------------------------------- +# initialization +#--------------------------------------------------------- +ENCODING = sys.getfilesystemencoding() +if ENCODING is None: + ENCODING = sys.getdefaultencoding() + +#--------------------------------------------------------- +# Some useful functions +#--------------------------------------------------------- + +def stn(s, length): + """Convert a python string to a null-terminated string buffer. + """ + return s[:length] + (length - len(s)) * NUL + +def nts(s): + """Convert a null-terminated string field to a python string. + """ + # Use the string up to the first null char. + p = s.find("\0") + if p == -1: + return s + return s[:p] + +def nti(s): + """Convert a number field to a python number. + """ + # There are two possible encodings for a number field, see + # itn() below. + if s[0] != chr(0200): + try: + n = int(nts(s).strip() or "0", 8) + except ValueError: + raise InvalidHeaderError("invalid header") + else: + n = 0L + for i in xrange(len(s) - 1): + n <<= 8 + n += ord(s[i + 1]) + return n + +def itn(n, digits=8, format=DEFAULT_FORMAT): + """Convert a python number to a number field. + """ + # POSIX 1003.1-1988 requires numbers to be encoded as a string of + # octal digits followed by a null-byte, this allows values up to + # (8**(digits-1))-1. GNU tar allows storing numbers greater than + # that if necessary. A leading 0200 byte indicates this particular + # encoding, the following digits-1 bytes are a big-endian + # representation. This allows values up to (256**(digits-1))-1. + if 0 <= n < 8 ** (digits - 1): + s = "%0*o" % (digits - 1, n) + NUL + else: + if format != GNU_FORMAT or n >= 256 ** (digits - 1): + raise ValueError("overflow in number field") + + if n < 0: + # XXX We mimic GNU tar's behaviour with negative numbers, + # this could raise OverflowError. + n = struct.unpack("L", struct.pack("l", n))[0] + + s = "" + for i in xrange(digits - 1): + s = chr(n & 0377) + s + n >>= 8 + s = chr(0200) + s + return s + +def uts(s, encoding, errors): + """Convert a unicode object to a string. + """ + if errors == "utf-8": + # An extra error handler similar to the -o invalid=UTF-8 option + # in POSIX.1-2001. Replace untranslatable characters with their + # UTF-8 representation. + try: + return s.encode(encoding, "strict") + except UnicodeEncodeError: + x = [] + for c in s: + try: + x.append(c.encode(encoding, "strict")) + except UnicodeEncodeError: + x.append(c.encode("utf8")) + return "".join(x) + else: + return s.encode(encoding, errors) + +def calc_chksums(buf): + """Calculate the checksum for a member's header by summing up all + characters except for the chksum field which is treated as if + it was filled with spaces. According to the GNU tar sources, + some tars (Sun and NeXT) calculate chksum with signed char, + which will be different if there are chars in the buffer with + the high bit set. So we calculate two checksums, unsigned and + signed. + """ + unsigned_chksum = 256 + sum(struct.unpack("148B", buf[:148]) + struct.unpack("356B", buf[156:512])) + signed_chksum = 256 + sum(struct.unpack("148b", buf[:148]) + struct.unpack("356b", buf[156:512])) + return unsigned_chksum, signed_chksum + +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) + +class TarError(Exception): + """Base exception.""" + pass +class ExtractError(TarError): + """General exception for extract errors.""" + pass +class ReadError(TarError): + """Exception for unreadable tar archives.""" + pass +class CompressionError(TarError): + """Exception for unavailable compression methods.""" + pass +class StreamError(TarError): + """Exception for unsupported operations on stream-like TarFiles.""" + pass +class HeaderError(TarError): + """Base exception for header errors.""" + pass +class EmptyHeaderError(HeaderError): + """Exception for empty headers.""" + pass +class TruncatedHeaderError(HeaderError): + """Exception for truncated headers.""" + pass +class EOFHeaderError(HeaderError): + """Exception for end of file headers.""" + pass +class InvalidHeaderError(HeaderError): + """Exception for invalid headers.""" + pass +class SubsequentHeaderError(HeaderError): + """Exception for missing and invalid extended headers.""" + 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, 0666) + + 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, comptype, fileobj, bufsize): + """Construct a _Stream object. + """ + self._extfileobj = True + if fileobj is None: + fileobj = _LowLevelFile(name, mode) + self._extfileobj = False + + if comptype == '*': + # Enable transparent compression detection for the + # stream interface + fileobj = _StreamProxy(fileobj) + comptype = fileobj.getcomptype() + + self.name = name or "" + self.mode = mode + self.comptype = comptype + self.fileobj = fileobj + self.bufsize = bufsize + self.buf = "" + self.pos = 0L + self.closed = False + + try: + if comptype == "gz": + try: + import zlib + except ImportError: + raise CompressionError("zlib module is not available") + self.zlib = zlib + self.crc = zlib.crc32("") & 0xffffffffL + if mode == "r": + self._init_read_gz() + else: + self._init_write_gz() + + elif comptype == "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() + except: + if not self._extfileobj: + self.fileobj.close() + self.closed = True + raise + + def __del__(self): + if hasattr(self, "closed") and 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(" 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 + + self.closed = True + try: + if self.mode == "w" and self.comptype != "tar": + self.buf += self.cmp.flush() + + if self.mode == "w" and self.buf: + self.fileobj.write(self.buf) + self.buf = "" + if self.comptype == "gz": + # The native zlib crc is an unsigned 32-bit integer, but + # the Python wrapper implicitly casts that to a signed C + # long. So, on a 32-bit box self.crc may "look negative", + # while the same crc on a 64-bit box may "look positive". + # To avoid irksome warnings from the `struct` module, force + # it to look positive on all boxes. + self.fileobj.write(struct.pack("= 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.comptype == "tar": + return self.__read(size) + + c = len(self.dbuf) + t = [self.dbuf] + while c < size: + buf = self.__read(self.bufsize) + if not buf: + break + try: + buf = self.cmp.decompress(buf) + except IOError: + raise ReadError("invalid compressed data") + 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 + +class _StreamProxy(object): + """Small proxy class that enables transparent compression + detection for the Stream interface (mode 'r|*'). + """ + + def __init__(self, fileobj): + self.fileobj = fileobj + self.buf = self.fileobj.read(BLOCKSIZE) + + def read(self, size): + self.read = self.fileobj.read + return self.buf + + def getcomptype(self): + if self.buf.startswith("\037\213\010"): + return "gz" + if self.buf[0:3] == "BZh" and self.buf[4:10] == "1AY&SY": + return "bz2" + return "tar" + + def close(self): + self.fileobj.close() +# class StreamProxy + +class _BZ2Proxy(object): + """Small proxy class that enables external file object + support for "r:bz2" and "w:bz2" modes. This is actually + a workaround for a limitation in bz2 module's BZ2File + class which (unlike gzip.GzipFile) has no support for + a file object argument. + """ + + blocksize = 16 * 1024 + + def __init__(self, fileobj, mode): + self.fileobj = fileobj + self.mode = mode + self.name = getattr(self.fileobj, "name", None) + self.init() + + def init(self): + import bz2 + self.pos = 0 + if self.mode == "r": + self.bz2obj = bz2.BZ2Decompressor() + self.fileobj.seek(0) + self.buf = "" + else: + self.bz2obj = bz2.BZ2Compressor() + + def read(self, size): + b = [self.buf] + x = len(self.buf) + while x < size: + raw = self.fileobj.read(self.blocksize) + if not raw: + break + data = self.bz2obj.decompress(raw) + b.append(data) + x += len(data) + self.buf = "".join(b) + + buf = self.buf[:size] + self.buf = self.buf[size:] + self.pos += len(buf) + return buf + + def seek(self, pos): + if pos < self.pos: + self.init() + self.read(pos - self.pos) + + def tell(self): + return self.pos + + def write(self, data): + self.pos += len(data) + raw = self.bz2obj.compress(data) + self.fileobj.write(raw) + + def close(self): + if self.mode == "w": + raw = self.bz2obj.flush() + self.fileobj.write(raw) +# class _BZ2Proxy + +#------------------------ +# Extraction file object +#------------------------ +class _FileInFile(object): + """A thin wrapper around an existing file object that + provides a part of its data as an individual file + object. + """ + + def __init__(self, fileobj, offset, size, sparse=None): + self.fileobj = fileobj + self.offset = offset + self.size = size + self.sparse = sparse + self.position = 0 + + def tell(self): + """Return the current file position. + """ + return self.position + + def seek(self, position): + """Seek to a position in the file. + """ + self.position = position + + def read(self, size=None): + """Read data from the file. + """ + if size is None: + size = self.size - self.position + else: + size = min(size, self.size - self.position) + + if self.sparse is None: + return self.readnormal(size) + else: + return self.readsparse(size) + + def __read(self, size): + buf = self.fileobj.read(size) + if len(buf) != size: + raise ReadError("unexpected end of data") + return buf + + def readnormal(self, size): + """Read operation for regular files. + """ + self.fileobj.seek(self.offset + self.position) + self.position += size + return self.__read(size) + + def readsparse(self, size): + """Read operation for sparse files. + """ + 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.position) + + if section is None: + return "" + + size = min(size, section.offset + section.size - self.position) + + if isinstance(section, _data): + realpos = section.realpos + self.position - section.offset + self.fileobj.seek(self.offset + realpos) + self.position += size + return self.__read(size) + else: + self.position += size + return NUL * size +#class _FileInFile + + +class ExFileObject(object): + """File-like object for reading an archive member. + Is returned by TarFile.extractfile(). + """ + blocksize = 1024 + + def __init__(self, tarfile, tarinfo): + self.fileobj = _FileInFile(tarfile.fileobj, + tarinfo.offset_data, + tarinfo.size, + getattr(tarinfo, "sparse", None)) + self.name = tarinfo.name + self.mode = "r" + self.closed = False + self.size = tarinfo.size + + self.position = 0 + self.buffer = "" + + def read(self, size=None): + """Read at most size bytes from the file. If size is not + present or None, read all data until EOF is reached. + """ + if self.closed: + raise ValueError("I/O operation on closed file") + + buf = "" + if self.buffer: + if size is None: + buf = self.buffer + self.buffer = "" + else: + buf = self.buffer[:size] + self.buffer = self.buffer[size:] + + if size is None: + buf += self.fileobj.read() + else: + buf += self.fileobj.read(size - len(buf)) + + self.position += len(buf) + return buf + + def readline(self, size=-1): + """Read one entire line from the file. If size is present + and non-negative, return a string with at most that + size, which may be an incomplete line. + """ + if self.closed: + raise ValueError("I/O operation on closed file") + + if "\n" in self.buffer: + pos = self.buffer.find("\n") + 1 + else: + buffers = [self.buffer] + while True: + buf = self.fileobj.read(self.blocksize) + buffers.append(buf) + if not buf or "\n" in buf: + self.buffer = "".join(buffers) + pos = self.buffer.find("\n") + 1 + if pos == 0: + # no newline found. + pos = len(self.buffer) + break + + if size != -1: + pos = min(size, pos) + + buf = self.buffer[:pos] + self.buffer = self.buffer[pos:] + self.position += len(buf) + return buf + + def readlines(self): + """Return a list with all remaining lines. + """ + result = [] + while True: + line = self.readline() + if not line: break + result.append(line) + return result + + def tell(self): + """Return the current file position. + """ + if self.closed: + raise ValueError("I/O operation on closed file") + + return self.position + + def seek(self, pos, whence=os.SEEK_SET): + """Seek to a position in the file. + """ + if self.closed: + raise ValueError("I/O operation on closed file") + + if whence == os.SEEK_SET: + self.position = min(max(pos, 0), self.size) + elif whence == os.SEEK_CUR: + if pos < 0: + self.position = max(self.position + pos, 0) + else: + self.position = min(self.position + pos, self.size) + elif whence == os.SEEK_END: + self.position = max(min(self.size + pos, self.size), 0) + else: + raise ValueError("Invalid argument") + + self.buffer = "" + self.fileobj.seek(self.position) + + def close(self): + """Close the file object. + """ + self.closed = True + + def __iter__(self): + """Get an iterator over the file's lines. + """ + while True: + line = self.readline() + if not line: + break + yield line +#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 + self.mode = 0644 # 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 name + self.gname = "" # group name + self.devmajor = 0 # device major number + self.devminor = 0 # device minor number + + self.offset = 0 # the tar header starts here + self.offset_data = 0 # the file's data starts here + + self.pax_headers = {} # pax header information + + # In pax headers the "name" and "linkname" field are called + # "path" and "linkpath". + def _getpath(self): + return self.name + def _setpath(self, name): + self.name = name + path = property(_getpath, _setpath) + + def _getlinkpath(self): + return self.linkname + def _setlinkpath(self, linkname): + self.linkname = linkname + linkpath = property(_getlinkpath, _setlinkpath) + + def __repr__(self): + return "<%s %r at %#x>" % (self.__class__.__name__,self.name,id(self)) + + def get_info(self, encoding, errors): + """Return the TarInfo's attributes as a dictionary. + """ + info = { + "name": self.name, + "mode": self.mode & 07777, + "uid": self.uid, + "gid": self.gid, + "size": self.size, + "mtime": self.mtime, + "chksum": self.chksum, + "type": self.type, + "linkname": self.linkname, + "uname": self.uname, + "gname": self.gname, + "devmajor": self.devmajor, + "devminor": self.devminor + } + + if info["type"] == DIRTYPE and not info["name"].endswith("/"): + info["name"] += "/" + + for key in ("name", "linkname", "uname", "gname"): + if type(info[key]) is unicode: + info[key] = info[key].encode(encoding, errors) + + return info + + def tobuf(self, format=DEFAULT_FORMAT, encoding=ENCODING, errors="strict"): + """Return a tar header as a string of 512 byte blocks. + """ + info = self.get_info(encoding, errors) + + if format == USTAR_FORMAT: + return self.create_ustar_header(info) + elif format == GNU_FORMAT: + return self.create_gnu_header(info) + elif format == PAX_FORMAT: + return self.create_pax_header(info, encoding, errors) + else: + raise ValueError("invalid format") + + def create_ustar_header(self, info): + """Return the object as a ustar header block. + """ + info["magic"] = POSIX_MAGIC + + if len(info["linkname"]) > LENGTH_LINK: + raise ValueError("linkname is too long") + + if len(info["name"]) > LENGTH_NAME: + info["prefix"], info["name"] = self._posix_split_name(info["name"]) + + return self._create_header(info, USTAR_FORMAT) + + def create_gnu_header(self, info): + """Return the object as a GNU header block sequence. + """ + info["magic"] = GNU_MAGIC + + buf = "" + if len(info["linkname"]) > LENGTH_LINK: + buf += self._create_gnu_long_header(info["linkname"], GNUTYPE_LONGLINK) + + if len(info["name"]) > LENGTH_NAME: + buf += self._create_gnu_long_header(info["name"], GNUTYPE_LONGNAME) + + return buf + self._create_header(info, GNU_FORMAT) + + def create_pax_header(self, info, encoding, errors): + """Return the object as a ustar header block. If it cannot be + represented this way, prepend a pax extended header sequence + with supplement information. + """ + info["magic"] = POSIX_MAGIC + pax_headers = self.pax_headers.copy() + + # Test string fields for values that exceed the field length or cannot + # be represented in ASCII encoding. + for name, hname, length in ( + ("name", "path", LENGTH_NAME), ("linkname", "linkpath", LENGTH_LINK), + ("uname", "uname", 32), ("gname", "gname", 32)): + + if hname in pax_headers: + # The pax header has priority. + continue + + val = info[name].decode(encoding, errors) + + # Try to encode the string as ASCII. + try: + val.encode("ascii") + except UnicodeEncodeError: + pax_headers[hname] = val + continue + + if len(info[name]) > length: + pax_headers[hname] = val + + # Test number fields for values that exceed the field limit or values + # that like to be stored as float. + for name, digits in (("uid", 8), ("gid", 8), ("size", 12), ("mtime", 12)): + if name in pax_headers: + # The pax header has priority. Avoid overflow. + info[name] = 0 + continue + + val = info[name] + if not 0 <= val < 8 ** (digits - 1) or isinstance(val, float): + pax_headers[name] = unicode(val) + info[name] = 0 + + # Create a pax extended header if necessary. + if pax_headers: + buf = self._create_pax_generic_header(pax_headers) + else: + buf = "" + + return buf + self._create_header(info, USTAR_FORMAT) + + @classmethod + def create_pax_global_header(cls, pax_headers): + """Return the object as a pax global header block sequence. + """ + return cls._create_pax_generic_header(pax_headers, type=XGLTYPE) + + def _posix_split_name(self, name): + """Split a name longer than 100 chars into a prefix + and a name part. + """ + prefix = name[:LENGTH_PREFIX + 1] + while prefix and prefix[-1] != "/": + prefix = prefix[:-1] + + name = name[len(prefix):] + prefix = prefix[:-1] + + if not prefix or len(name) > LENGTH_NAME: + raise ValueError("name is too long") + return prefix, name + + @staticmethod + def _create_header(info, format): + """Return a header block. info is a dictionary with file + information, format must be one of the *_FORMAT constants. + """ + parts = [ + stn(info.get("name", ""), 100), + itn(info.get("mode", 0) & 07777, 8, format), + itn(info.get("uid", 0), 8, format), + itn(info.get("gid", 0), 8, format), + itn(info.get("size", 0), 12, format), + itn(info.get("mtime", 0), 12, format), + " ", # checksum field + info.get("type", REGTYPE), + stn(info.get("linkname", ""), 100), + stn(info.get("magic", POSIX_MAGIC), 8), + stn(info.get("uname", ""), 32), + stn(info.get("gname", ""), 32), + itn(info.get("devmajor", 0), 8, format), + itn(info.get("devminor", 0), 8, format), + stn(info.get("prefix", ""), 155) + ] + + buf = struct.pack("%ds" % BLOCKSIZE, "".join(parts)) + chksum = calc_chksums(buf[-BLOCKSIZE:])[0] + buf = buf[:-364] + "%06o\0" % chksum + buf[-357:] + return buf + + @staticmethod + def _create_payload(payload): + """Return the string payload filled with zero bytes + up to the next 512 byte border. + """ + blocks, remainder = divmod(len(payload), BLOCKSIZE) + if remainder > 0: + payload += (BLOCKSIZE - remainder) * NUL + return payload + + @classmethod + def _create_gnu_long_header(cls, name, type): + """Return a GNUTYPE_LONGNAME or GNUTYPE_LONGLINK sequence + for name. + """ + name += NUL + + info = {} + info["name"] = "././@LongLink" + info["type"] = type + info["size"] = len(name) + info["magic"] = GNU_MAGIC + + # create extended header + name blocks. + return cls._create_header(info, USTAR_FORMAT) + \ + cls._create_payload(name) + + @classmethod + def _create_pax_generic_header(cls, pax_headers, type=XHDTYPE): + """Return a POSIX.1-2001 extended or global header sequence + that contains a list of keyword, value pairs. The values + must be unicode objects. + """ + records = [] + for keyword, value in pax_headers.iteritems(): + keyword = keyword.encode("utf8") + value = value.encode("utf8") + l = len(keyword) + len(value) + 3 # ' ' + '=' + '\n' + n = p = 0 + while True: + n = l + len(str(p)) + if n == p: + break + p = n + records.append("%d %s=%s\n" % (p, keyword, value)) + records = "".join(records) + + # We use a hardcoded "././@PaxHeader" name like star does + # instead of the one that POSIX recommends. + info = {} + info["name"] = "././@PaxHeader" + info["type"] = type + info["size"] = len(records) + info["magic"] = POSIX_MAGIC + + # Create pax header + record blocks. + return cls._create_header(info, USTAR_FORMAT) + \ + cls._create_payload(records) + + @classmethod + def frombuf(cls, buf): + """Construct a TarInfo object from a 512 byte string buffer. + """ + if len(buf) == 0: + raise EmptyHeaderError("empty header") + if len(buf) != BLOCKSIZE: + raise TruncatedHeaderError("truncated header") + if buf.count(NUL) == BLOCKSIZE: + raise EOFHeaderError("end of file header") + + chksum = nti(buf[148:156]) + if chksum not in calc_chksums(buf): + raise InvalidHeaderError("bad checksum") + + obj = cls() + obj.buf = buf + obj.name = nts(buf[0:100]) + obj.mode = nti(buf[100:108]) + obj.uid = nti(buf[108:116]) + obj.gid = nti(buf[116:124]) + obj.size = nti(buf[124:136]) + obj.mtime = nti(buf[136:148]) + obj.chksum = chksum + obj.type = buf[156:157] + obj.linkname = nts(buf[157:257]) + obj.uname = nts(buf[265:297]) + obj.gname = nts(buf[297:329]) + obj.devmajor = nti(buf[329:337]) + obj.devminor = nti(buf[337:345]) + prefix = nts(buf[345:500]) + + # Old V7 tar format represents a directory as a regular + # file with a trailing slash. + if obj.type == AREGTYPE and obj.name.endswith("/"): + obj.type = DIRTYPE + + # Remove redundant slashes from directories. + if obj.isdir(): + obj.name = obj.name.rstrip("/") + + # Reconstruct a ustar longname. + if prefix and obj.type not in GNU_TYPES: + obj.name = prefix + "/" + obj.name + return obj + + @classmethod + def fromtarfile(cls, tarfile): + """Return the next TarInfo object from TarFile object + tarfile. + """ + buf = tarfile.fileobj.read(BLOCKSIZE) + obj = cls.frombuf(buf) + obj.offset = tarfile.fileobj.tell() - BLOCKSIZE + return obj._proc_member(tarfile) + + #-------------------------------------------------------------------------- + # The following are methods that are called depending on the type of a + # member. The entry point is _proc_member() which can be overridden in a + # subclass to add custom _proc_*() methods. A _proc_*() method MUST + # implement the following + # operations: + # 1. Set self.offset_data to the position where the data blocks begin, + # if there is data that follows. + # 2. Set tarfile.offset to the position where the next member's header will + # begin. + # 3. Return self or another valid TarInfo object. + def _proc_member(self, tarfile): + """Choose the right processing method depending on + the type and call it. + """ + if self.type in (GNUTYPE_LONGNAME, GNUTYPE_LONGLINK): + return self._proc_gnulong(tarfile) + elif self.type == GNUTYPE_SPARSE: + return self._proc_sparse(tarfile) + elif self.type in (XHDTYPE, XGLTYPE, SOLARIS_XHDTYPE): + return self._proc_pax(tarfile) + else: + return self._proc_builtin(tarfile) + + def _proc_builtin(self, tarfile): + """Process a builtin type or an unknown type which + will be treated as a regular file. + """ + self.offset_data = tarfile.fileobj.tell() + offset = self.offset_data + if self.isreg() or self.type not in SUPPORTED_TYPES: + # Skip the following data blocks. + offset += self._block(self.size) + tarfile.offset = offset + + # Patch the TarInfo object with saved global + # header information. + self._apply_pax_info(tarfile.pax_headers, tarfile.encoding, tarfile.errors) + + return self + + def _proc_gnulong(self, tarfile): + """Process the blocks that hold a GNU longname + or longlink member. + """ + buf = tarfile.fileobj.read(self._block(self.size)) + + # Fetch the next header and process it. + try: + next = self.fromtarfile(tarfile) + except HeaderError: + raise SubsequentHeaderError("missing or bad subsequent header") + + # Patch the TarInfo object from the next header with + # the longname information. + next.offset = self.offset + if self.type == GNUTYPE_LONGNAME: + next.name = nts(buf) + elif self.type == GNUTYPE_LONGLINK: + next.linkname = nts(buf) + + return next + + def _proc_sparse(self, tarfile): + """Process a GNU sparse header plus extra headers. + """ + buf = self.buf + 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 = nti(buf[pos:pos + 12]) + numbytes = nti(buf[pos + 12:pos + 24]) + 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 = nti(buf[483:495]) + + # If the isextended flag is given, + # there are extra headers to process. + while isextended == 1: + buf = tarfile.fileobj.read(BLOCKSIZE) + pos = 0 + for i in xrange(21): + try: + offset = nti(buf[pos:pos + 12]) + numbytes = nti(buf[pos + 12:pos + 24]) + 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)) + + self.sparse = sp + + self.offset_data = tarfile.fileobj.tell() + tarfile.offset = self.offset_data + self._block(self.size) + self.size = origsize + + return self + + def _proc_pax(self, tarfile): + """Process an extended or global header as described in + POSIX.1-2001. + """ + # Read the header information. + buf = tarfile.fileobj.read(self._block(self.size)) + + # A pax header stores supplemental information for either + # the following file (extended) or all following files + # (global). + if self.type == XGLTYPE: + pax_headers = tarfile.pax_headers + else: + pax_headers = tarfile.pax_headers.copy() + + # Parse pax header information. A record looks like that: + # "%d %s=%s\n" % (length, keyword, value). length is the size + # of the complete record including the length field itself and + # the newline. keyword and value are both UTF-8 encoded strings. + regex = re.compile(r"(\d+) ([^=]+)=", re.U) + pos = 0 + while True: + match = regex.match(buf, pos) + if not match: + break + + length, keyword = match.groups() + length = int(length) + value = buf[match.end(2) + 1:match.start(1) + length - 1] + + try: + keyword = keyword.decode("utf8") + except UnicodeDecodeError: + pass + + try: + value = value.decode("utf8") + except UnicodeDecodeError: + pass + + pax_headers[keyword] = value + pos += length + + # Fetch the next header. + try: + next = self.fromtarfile(tarfile) + except HeaderError: + raise SubsequentHeaderError("missing or bad subsequent header") + + if self.type in (XHDTYPE, SOLARIS_XHDTYPE): + # Patch the TarInfo object with the extended header info. + next._apply_pax_info(pax_headers, tarfile.encoding, tarfile.errors) + next.offset = self.offset + + if "size" in pax_headers: + # If the extended header replaces the size field, + # we need to recalculate the offset where the next + # header starts. + offset = next.offset_data + if next.isreg() or next.type not in SUPPORTED_TYPES: + offset += next._block(next.size) + tarfile.offset = offset + + return next + + def _apply_pax_info(self, pax_headers, encoding, errors): + """Replace fields with supplemental information from a previous + pax extended or global header. + """ + for keyword, value in pax_headers.iteritems(): + if keyword not in PAX_FIELDS: + continue + + if keyword == "path": + value = value.rstrip("/") + + if keyword in PAX_NUMBER_FIELDS: + try: + value = PAX_NUMBER_FIELDS[keyword](value) + except ValueError: + value = 0 + else: + value = uts(value, encoding, errors) + + setattr(self, keyword, value) + + self.pax_headers = pax_headers.copy() + + 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 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 = 1 # If 0, fatal errors only appear in debug + # messages (if debug >= 0). If > 0, errors + # are passed to the caller as exceptions. + + format = DEFAULT_FORMAT # The format to use when creating an archive. + + encoding = ENCODING # Encoding for 8-bit character strings. + + errors = None # Error handler for unicode conversion. + + tarinfo = TarInfo # The default TarInfo class to use. + + fileobject = ExFileObject # The default ExFileObject class to use. + + def __init__(self, name=None, mode="r", fileobj=None, format=None, + tarinfo=None, dereference=None, ignore_zeros=None, encoding=None, + errors=None, pax_headers=None, debug=None, errorlevel=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. + """ + modes = {"r": "rb", "a": "r+b", "w": "wb"} + if mode not in modes: + raise ValueError("mode must be 'r', 'a' or 'w'") + self.mode = mode + self._mode = modes[mode] + + if not fileobj: + if self.mode == "a" and not os.path.exists(name): + # Create nonexistent files in append mode. + self.mode = "w" + self._mode = "wb" + fileobj = bltn_open(name, self._mode) + self._extfileobj = False + else: + if name is None and hasattr(fileobj, "name"): + name = fileobj.name + if hasattr(fileobj, "mode"): + self._mode = fileobj.mode + self._extfileobj = True + self.name = os.path.abspath(name) if name else None + self.fileobj = fileobj + + # Init attributes. + if format is not None: + self.format = format + if tarinfo is not None: + self.tarinfo = tarinfo + if dereference is not None: + self.dereference = dereference + if ignore_zeros is not None: + self.ignore_zeros = ignore_zeros + if encoding is not None: + self.encoding = encoding + + if errors is not None: + self.errors = errors + elif mode == "r": + self.errors = "utf-8" + else: + self.errors = "strict" + + if pax_headers is not None and self.format == PAX_FORMAT: + self.pax_headers = pax_headers + else: + self.pax_headers = {} + + if debug is not None: + self.debug = debug + if errorlevel is not None: + self.errorlevel = errorlevel + + # 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 = self.fileobj.tell() + # current position in the archive file + self.inodes = {} # dictionary caching the inodes of + # archive members already added + + try: + 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. + while True: + self.fileobj.seek(self.offset) + try: + tarinfo = self.tarinfo.fromtarfile(self) + self.members.append(tarinfo) + except EOFHeaderError: + self.fileobj.seek(self.offset) + break + except HeaderError, e: + raise ReadError(str(e)) + + if self.mode in "aw": + self._loaded = True + + if self.pax_headers: + buf = self.tarinfo.create_pax_global_header(self.pax_headers.copy()) + self.fileobj.write(buf) + self.offset += len(buf) + except: + if not self._extfileobj: + self.fileobj.close() + self.closed = True + raise + + def _getposix(self): + return self.format == USTAR_FORMAT + def _setposix(self, value): + import warnings + warnings.warn("use the format attribute instead", DeprecationWarning, + 2) + if value: + self.format = USTAR_FORMAT + else: + self.format = GNU_FORMAT + posix = property(_getposix, _setposix) + + #-------------------------------------------------------------------------- + # 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. + + @classmethod + def open(cls, name=None, mode="r", fileobj=None, bufsize=RECORDSIZE, **kwargs): + """Open a tar archive for reading, writing or appending. Return + an appropriate TarFile class. + + mode: + 'r' or '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, creating the file if necessary + '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 a stream of tar blocks with transparent 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 mode in ("r", "r:*"): + # Find out which *open() is appropriate for opening the file. + for comptype in cls.OPEN_METH: + func = getattr(cls, cls.OPEN_METH[comptype]) + if fileobj is not None: + saved_pos = fileobj.tell() + try: + return func(name, "r", fileobj, **kwargs) + except (ReadError, CompressionError), e: + if fileobj is not None: + fileobj.seek(saved_pos) + continue + raise ReadError("file could not be opened successfully") + + elif ":" 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, **kwargs) + + elif "|" in mode: + filemode, comptype = mode.split("|", 1) + filemode = filemode or "r" + comptype = comptype or "tar" + + if filemode not in ("r", "w"): + raise ValueError("mode must be 'r' or 'w'") + + stream = _Stream(name, filemode, comptype, fileobj, bufsize) + try: + t = cls(name, filemode, stream, **kwargs) + except: + stream.close() + raise + t._extfileobj = False + return t + + elif mode in ("a", "w"): + return cls.taropen(name, mode, fileobj, **kwargs) + + raise ValueError("undiscernible mode") + + @classmethod + def taropen(cls, name, mode="r", fileobj=None, **kwargs): + """Open uncompressed tar archive name for reading or writing. + """ + if mode not in ("r", "a", "w"): + raise ValueError("mode must be 'r', 'a' or 'w'") + return cls(name, mode, fileobj, **kwargs) + + @classmethod + def gzopen(cls, name, mode="r", fileobj=None, compresslevel=9, **kwargs): + """Open gzip compressed tar archive name for reading or writing. + Appending is not allowed. + """ + if mode not in ("r", "w"): + raise ValueError("mode must be 'r' or 'w'") + + try: + import gzip + gzip.GzipFile + except (ImportError, AttributeError): + raise CompressionError("gzip module is not available") + + try: + fileobj = gzip.GzipFile(name, mode, compresslevel, fileobj) + except OSError: + if fileobj is not None and mode == 'r': + raise ReadError("not a gzip file") + raise + + try: + t = cls.taropen(name, mode, fileobj, **kwargs) + except IOError: + fileobj.close() + if mode == 'r': + raise ReadError("not a gzip file") + raise + except: + fileobj.close() + raise + t._extfileobj = False + return t + + @classmethod + def bz2open(cls, name, mode="r", fileobj=None, compresslevel=9, **kwargs): + """Open bzip2 compressed tar archive name for reading or writing. + Appending is not allowed. + """ + if mode not in ("r", "w"): + raise ValueError("mode must be 'r' or 'w'.") + + try: + import bz2 + except ImportError: + raise CompressionError("bz2 module is not available") + + if fileobj is not None: + fileobj = _BZ2Proxy(fileobj, mode) + else: + fileobj = bz2.BZ2File(name, mode, compresslevel=compresslevel) + + try: + t = cls.taropen(name, mode, fileobj, **kwargs) + except (IOError, EOFError): + fileobj.close() + if mode == 'r': + raise ReadError("not a bzip2 file") + raise + except: + fileobj.close() + raise + t._extfileobj = False + return t + + # 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 + + self.closed = True + try: + 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)) + finally: + if not self._extfileobj: + self.fileobj.close() + + 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 occurrence 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 + drv, arcname = os.path.splitdrive(arcname) + arcname = arcname.replace(os.sep, "/") + arcname = arcname.lstrip("/") + + # Now, fill the TarInfo object with + # information specific for the file. + tarinfo = self.tarinfo() + tarinfo.tarfile = self + + # 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 not self.dereference and statres.st_nlink > 1 and \ + inode in self.inodes and arcname != self.inodes[inode]: + # 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 + 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 type == REGTYPE: + tarinfo.size = statres.st_size + else: + tarinfo.size = 0L + 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 tarinfo.isdir() else ""), + + 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, exclude=None, filter=None): + """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. `exclude' is a function that should + return True for each filename to be excluded. `filter' is a function + that expects a TarInfo object argument and returns the changed + TarInfo object, if it returns None the TarInfo object will be + excluded from the archive. + """ + self._check("aw") + + if arcname is None: + arcname = name + + # Exclude pathnames. + if exclude is not None: + import warnings + warnings.warn("use the filter argument instead", + DeprecationWarning, 2) + if exclude(name): + self._dbg(2, "tarfile: Excluded %r" % name) + return + + # Skip if somebody tries to archive the archive... + if self.name is not None and os.path.abspath(name) == self.name: + self._dbg(2, "tarfile: Skipped %r" % name) + 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 + + # Change or exclude the TarInfo object. + if filter is not None: + tarinfo = filter(tarinfo) + if tarinfo is None: + self._dbg(2, "tarfile: Excluded %r" % name) + return + + # Append the tar header and data to the archive. + if tarinfo.isreg(): + with bltn_open(name, "rb") as f: + self.addfile(tarinfo, f) + + elif 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), + recursive, exclude, filter) + + else: + self.addfile(tarinfo) + + 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 = copy.copy(tarinfo) + + buf = tarinfo.tobuf(self.format, self.encoding, self.errors) + self.fileobj.write(buf) + self.offset += len(buf) + + # 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 extractall(self, path=".", members=None): + """Extract all members from the archive to the current working + directory and set owner, modification time and permissions on + directories afterwards. `path' specifies a different directory + to extract to. `members' is optional and must be a subset of the + list returned by getmembers(). + """ + directories = [] + + if members is None: + members = self + + for tarinfo in members: + if tarinfo.isdir(): + # Extract directories with a safe mode. + directories.append(tarinfo) + tarinfo = copy.copy(tarinfo) + tarinfo.mode = 0700 + self.extract(tarinfo, path) + + # Reverse sort directories. + directories.sort(key=operator.attrgetter('name')) + directories.reverse() + + # Set correct owner, mtime and filemode on directories. + for tarinfo in directories: + dirpath = os.path.join(path, tarinfo.name) + try: + self.chown(tarinfo, dirpath) + self.utime(tarinfo, dirpath) + self.chmod(tarinfo, dirpath) + except ExtractError, e: + if self.errorlevel > 1: + raise + else: + self._dbg(1, "tarfile: %s" % e) + + 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, basestring): + tarinfo = self.getmember(member) + else: + tarinfo = 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, basestring): + tarinfo = self.getmember(member) + else: + tarinfo = 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 its target's file object. + return self.extractfile(self._find_link_target(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. + targetpath = targetpath.rstrip("/") + targetpath = targetpath.replace("/", os.sep) + + # Create all upper directories. + upperdirs = os.path.dirname(targetpath) + if upperdirs and not os.path.exists(upperdirs): + # Create directories that are not part of the archive with + # default permissions. + os.makedirs(upperdirs) + + 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: + # Use a safe mode for the directory, the real mode is set + # later in _extract_member(). + os.mkdir(targetpath, 0700) + except EnvironmentError, e: + if e.errno != errno.EEXIST: + raise + + def makefile(self, tarinfo, targetpath): + """Make a file called targetpath. + """ + source = self.extractfile(tarinfo) + try: + with bltn_open(targetpath, "wb") as target: + copyfileobj(source, target) + finally: + source.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. + """ + if hasattr(os, "symlink") and hasattr(os, "link"): + # For systems that support symbolic and hard links. + if tarinfo.issym(): + if os.path.lexists(targetpath): + os.unlink(targetpath) + os.symlink(tarinfo.linkname, targetpath) + else: + # See extract(). + if os.path.exists(tarinfo._link_target): + if os.path.lexists(targetpath): + os.unlink(targetpath) + os.link(tarinfo._link_target, targetpath) + else: + self._extract_member(self._find_link_target(tarinfo), targetpath) + else: + try: + self._extract_member(self._find_link_target(tarinfo), targetpath) + except KeyError: + raise ExtractError("unable to resolve link inside archive") + + 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: + g = tarinfo.gid + try: + u = pwd.getpwnam(tarinfo.uname)[2] + except KeyError: + u = tarinfo.uid + 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 + 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 + + # Advance the file pointer. + if self.offset != self.fileobj.tell(): + self.fileobj.seek(self.offset - 1) + if not self.fileobj.read(1): + raise ReadError("unexpected end of data") + + # Read the next block. + tarinfo = None + while True: + try: + tarinfo = self.tarinfo.fromtarfile(self) + except EOFHeaderError, e: + if self.ignore_zeros: + self._dbg(2, "0x%X: %s" % (self.offset, e)) + self.offset += BLOCKSIZE + continue + except InvalidHeaderError, e: + if self.ignore_zeros: + self._dbg(2, "0x%X: %s" % (self.offset, e)) + self.offset += BLOCKSIZE + continue + elif self.offset == 0: + raise ReadError(str(e)) + except EmptyHeaderError: + if self.offset == 0: + raise ReadError("empty file") + except TruncatedHeaderError, e: + if self.offset == 0: + raise ReadError(str(e)) + except SubsequentHeaderError, e: + raise ReadError(str(e)) + break + + if tarinfo is not None: + self.members.append(tarinfo) + else: + self._loaded = True + + return tarinfo + + #-------------------------------------------------------------------------- + # Little helper methods: + + def _getmember(self, name, tarinfo=None, normalize=False): + """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() + + # Limit the member search list up to tarinfo. + if tarinfo is not None: + members = members[:members.index(tarinfo)] + + if normalize: + name = os.path.normpath(name) + + for member in reversed(members): + if normalize: + member_name = os.path.normpath(member.name) + else: + member_name = member.name + + if name == member_name: + return member + + 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 _find_link_target(self, tarinfo): + """Find the target member of a symlink or hardlink member in the + archive. + """ + if tarinfo.issym(): + # Always search the entire archive. + linkname = "/".join(filter(None, (os.path.dirname(tarinfo.name), tarinfo.linkname))) + limit = None + else: + # Search the archive before the link, because a hard link is + # just a reference to an already archived file. + linkname = tarinfo.linkname + limit = tarinfo + + member = self._getmember(linkname, tarinfo=limit, normalize=True) + if member is None: + raise KeyError("linkname %r not found" % linkname) + return member + + def __iter__(self): + """Provide an iterator object. + """ + if self._loaded: + return iter(self.members) + else: + return TarIter(self) + + def _dbg(self, level, msg): + """Write debugging output to sys.stderr. + """ + if level <= self.debug: + print >> sys.stderr, msg + + def __enter__(self): + self._check() + return self + + def __exit__(self, type, value, traceback): + if type is None: + self.close() + else: + # An exception occurred. We must not call close() because + # it would try to write end-of-archive blocks and padding. + if not self._extfileobj: + self.fileobj.close() + self.closed = True +# class TarFile + +class TarIter: + """Iterator Class. + + for tarinfo in TarFile(...): + suite... + """ + + def __init__(self, tarfile): + """Construct a TarIter object. + """ + self.tarfile = tarfile + self.index = 0 + 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. + """ + # Fix for SF #1100429: Under rare circumstances it can + # happen that getmembers() is called during iteration, + # which will cause TarIter to stop prematurely. + + if self.index == 0 and self.tarfile.firstmember is not None: + tarinfo = self.tarfile.next() + elif self.index < len(self.tarfile.members): + tarinfo = self.tarfile.members[self.index] + elif not self.tarfile._loaded: + tarinfo = self.tarfile.next() + if not tarinfo: + self.tarfile._loaded = True + raise StopIteration + else: + raise StopIteration + self.index += 1 + 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): + from warnings import warnpy3k + warnpy3k("the TarFileCompat class has been removed in Python 3.0", + stacklevel=2) + 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 m in members: + 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 + tinfo = TarInfo(zinfo.filename) + tinfo.size = len(bytes) + tinfo.mtime = calendar.timegm(zinfo.date_time) + self.tarfile.addfile(tinfo, 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