diff options
Diffstat (limited to 'Lib/tarfile.py')
| -rw-r--r-- | Lib/tarfile.py | 179 |
1 files changed, 88 insertions, 91 deletions
diff --git a/Lib/tarfile.py b/Lib/tarfile.py index d238063..14553a7 100644 --- a/Lib/tarfile.py +++ b/Lib/tarfile.py @@ -49,6 +49,7 @@ import stat import errno import time import struct +import copy if sys.platform == 'mac': # This module needs work for MacOS9, especially in the area of pathname @@ -138,7 +139,7 @@ TOEXEC = 0001 # execute/search by other def stn(s, length): """Convert a python string to a null-terminated string buffer. """ - return s[:length-1] + (length - len(s) - 1) * NUL + NUL + return s[:length] + (length - len(s)) * NUL def nti(s): """Convert a number field to a python number. @@ -146,7 +147,7 @@ def nti(s): # There are two possible encodings for a number field, see # itn() below. if s[0] != chr(0200): - n = int(s.rstrip(NUL) or "0", 8) + n = int(s.rstrip(NUL + " ") or "0", 8) else: n = 0L for i in xrange(len(s) - 1): @@ -795,7 +796,6 @@ class TarInfo(object): """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 @@ -809,8 +809,6 @@ class TarInfo(object): self.gname = "group" # group name self.devmajor = 0 # device major number self.devminor = 0 # device minor number - self.prefix = "" # prefix to filename or information - # about sparse files self.offset = 0 # the tar header starts here self.offset_data = 0 # the file's data starts here @@ -842,24 +840,74 @@ class TarInfo(object): tarinfo.gname = buf[297:329].rstrip(NUL) tarinfo.devmajor = nti(buf[329:337]) tarinfo.devminor = nti(buf[337:345]) - tarinfo.prefix = buf[345:500] + prefix = buf[345:500].rstrip(NUL) + + if prefix and not tarinfo.issparse(): + tarinfo.name = prefix + "/" + tarinfo.name if tarinfo.chksum not in calc_chksums(buf): raise ValueError("invalid header") return tarinfo def tobuf(self, posix=False): - """Return a tar header block as a 512 byte string. + """Return a tar header as a string of 512 byte blocks. """ + buf = "" + type = self.type + prefix = "" + + if self.name.endswith("/"): + type = DIRTYPE + + if type in (GNUTYPE_LONGNAME, GNUTYPE_LONGLINK): + # Prevent "././@LongLink" from being normalized. + name = self.name + else: + name = normpath(self.name) + + if type == DIRTYPE: + # directories should end with '/' + name += "/" + + linkname = self.linkname + if linkname: + # if linkname is empty we end up with a '.' + linkname = normpath(linkname) + + if posix: + if self.size > MAXSIZE_MEMBER: + raise ValueError("file is too large (>= 8 GB)") + + if len(self.linkname) > LENGTH_LINK: + raise ValueError("linkname is too long (>%d)" % (LENGTH_LINK)) + + if len(name) > LENGTH_NAME: + 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") + + else: + if len(self.linkname) > LENGTH_LINK: + buf += self._create_gnulong(self.linkname, GNUTYPE_LONGLINK) + + if len(name) > LENGTH_NAME: + buf += self._create_gnulong(name, GNUTYPE_LONGNAME) + parts = [ - stn(self.name, 100), + stn(name, 100), itn(self.mode & 07777, 8, posix), itn(self.uid, 8, posix), itn(self.gid, 8, posix), itn(self.size, 12, posix), itn(self.mtime, 12, posix), " ", # checksum field - self.type, + type, stn(self.linkname, 100), stn(MAGIC, 6), stn(VERSION, 2), @@ -867,15 +915,38 @@ class TarInfo(object): stn(self.gname, 32), itn(self.devmajor, 8, posix), itn(self.devminor, 8, posix), - stn(self.prefix, 155) + stn(prefix, 155) ] - buf = struct.pack("%ds" % BLOCKSIZE, "".join(parts)) - chksum = calc_chksums(buf)[0] - buf = buf[:148] + "%06o\0" % chksum + buf[155:] + buf += struct.pack("%ds" % BLOCKSIZE, "".join(parts)) + chksum = calc_chksums(buf[-BLOCKSIZE:])[0] + buf = buf[:-364] + "%06o\0" % chksum + buf[-357:] self.buf = buf return buf + def _create_gnulong(self, name, type): + """Create a GNU longname/longlink header from name. + 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 = self.__class__() + tarinfo.name = "././@LongLink" + tarinfo.type = type + tarinfo.mode = 0 + tarinfo.size = len(name) + + # create extended header + buf = tarinfo.tobuf() + # create name blocks + buf += name + blocks, remainder = divmod(len(name), BLOCKSIZE) + if remainder > 0: + buf += (BLOCKSIZE - remainder) * NUL + return buf + def isreg(self): return self.type in REGULAR_TYPES def isfile(self): @@ -1379,50 +1450,11 @@ class TarFile(object): """ 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") + tarinfo = copy.copy(tarinfo) - self.fileobj.write(tarinfo.tobuf(self.posix)) - self.offset += BLOCKSIZE + buf = tarinfo.tobuf(self.posix) + self.fileobj.write(buf) + self.offset += len(buf) # If there's data to follow, append it. if fileobj is not None: @@ -1781,12 +1813,6 @@ class TarFile(object): if tarinfo.isreg() and tarinfo.name.endswith("/"): tarinfo.type = DIRTYPE - # The prefix field is used for filenames > 100 in - # the POSIX standard. - # name = prefix + '/' + name - tarinfo.name = normpath(os.path.join(tarinfo.prefix.rstrip(NUL), - tarinfo.name)) - # Directory names should have a '/' at the end. if tarinfo.isdir(): tarinfo.name += "/" @@ -1911,10 +1937,6 @@ class TarFile(object): self.offset += self._block(tarinfo.size) tarinfo.size = origsize - # Clear the prefix field so that it is not used - # as a pathname in next(). - tarinfo.prefix = "" - return tarinfo #-------------------------------------------------------------------------- @@ -1972,31 +1994,6 @@ class TarFile(object): 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. """ |