From d96d1015ef1bc635e5bf758944a4ac89d60b131c Mon Sep 17 00:00:00 2001 From: Neal Norwitz Date: Tue, 20 Jul 2004 22:23:02 +0000 Subject: SF #918101, allow files >= 8 GB using GNU extension --- Doc/lib/libtarfile.tex | 11 ++++++----- Lib/tarfile.py | 38 ++++++++++++++++++++++++++++++++------ 2 files changed, 38 insertions(+), 11 deletions(-) diff --git a/Doc/lib/libtarfile.tex b/Doc/lib/libtarfile.tex index fec2737..c841123 100644 --- a/Doc/lib/libtarfile.tex +++ b/Doc/lib/libtarfile.tex @@ -256,11 +256,12 @@ tar archive several times. Each archive member is represented by a \begin{memberdesc}{posix} If true, create a \POSIX{} 1003.1-1990 compliant archive. GNU extensions are not used, because they are not part of the \POSIX{} - standard. This limits the length of filenames to at most 256 and - link names to 100 characters. A \exception{ValueError} is raised - if a pathname exceeds this limit. If false, create a GNU tar - compatible archive. It will not be \POSIX{} compliant, but can - store pathnames of unlimited length. + standard. This limits the length of filenames to at most 256, + link names to 100 characters and the maximum file size to 8 + gigabytes. A \exception{ValueError} is raised if a file exceeds + this limit. If false, create a GNU tar compatible archive. It + will not be \POSIX{} compliant, but can store files without any + of the above restrictions. \end{memberdesc} \begin{memberdesc}{dereference} diff --git a/Lib/tarfile.py b/Lib/tarfile.py index 077fbee..6462e7b 100644 --- a/Lib/tarfile.py +++ b/Lib/tarfile.py @@ -655,11 +655,21 @@ class TarInfo(object): """Construct a TarInfo object from a 512 byte string buffer. """ tarinfo = cls() - tarinfo.name = nts(buf[0:100]) + 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) - tarinfo.size = long(buf[124:136], 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] @@ -689,16 +699,28 @@ class TarInfo(object): def tobuf(self): """Return a tar header block as a 512 byte string. """ - name = self.name + # 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 ( - (name, 100), + (self.name, 100), ("%07o" % (self.mode & 07777), 8), ("%07o" % self.uid, 8), ("%07o" % self.gid, 8), - ("%011o" % self.size, 12), + (size, 12), ("%011o" % self.mtime, 12), (" ", 8), (self.type, 1), @@ -1236,7 +1258,11 @@ class TarFile(object): tarinfo.linkname = normpath(tarinfo.linkname) if tarinfo.size > MAXSIZE_MEMBER: - raise ValueError, "file is too large (>8GB)" + 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: -- cgit v0.12