f2f0267529
When we generate tar headers, we sprintf() values directly into a struct with the fixed-size header values. For the most part this is fine, as we are formatting small values (e.g., the octal format of "mode & 0x7777" is of fixed length). But it's still a good idea to use xsnprintf here. It communicates to readers what our expectation is, and it provides a run-time check that we are not overflowing the buffers. The one exception here is the mtime, which comes from the epoch time of the commit we are archiving. For sane values, this fits into the 12-byte value allocated in the header. But since git can handle 64-bit times, if I claim to be a visitor from the year 10,000 AD, I can overflow the buffer. This turns out to be harmless, as we simply overflow into the chksum field, which is then overwritten. This case is also best as an xsnprintf. It should never come up, short of extremely malformed dates, and in that case we are probably better off dying than silently truncating the date value (and we cannot expand the size of the buffer, since it is dictated by the ustar format). Our friends in the year 5138 (when we legitimately flip to a 12-digit epoch) can deal with that problem then. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Git - the stupid content tracker
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"git" can mean anything, depending on your mood.
- random three-letter combination that is pronounceable, and not
actually used by any common UNIX command. The fact that it is a
mispronunciation of "get" may or may not be relevant.
- stupid. contemptible and despicable. simple. Take your pick from the
dictionary of slang.
- "global information tracker": you're in a good mood, and it actually
works for you. Angels sing, and a light suddenly fills the room.
- "goddamn idiotic truckload of sh*t": when it breaks
Git is a fast, scalable, distributed revision control system with an
unusually rich command set that provides both high-level operations
and full access to internals.
Git is an Open Source project covered by the GNU General Public
License version 2 (some parts of it are under different licenses,
compatible with the GPLv2). It was originally written by Linus
Torvalds with help of a group of hackers around the net.
Please read the file INSTALL for installation instructions.
See Documentation/gittutorial.txt to get started, then see
Documentation/giteveryday.txt for a useful minimum set of commands, and
Documentation/git-commandname.txt for documentation of each command.
If git has been correctly installed, then the tutorial can also be
read with "man gittutorial" or "git help tutorial", and the
documentation of each command with "man git-commandname" or "git help
commandname".
CVS users may also want to read Documentation/gitcvs-migration.txt
("man gitcvs-migration" or "git help cvs-migration" if git is
installed).
Many Git online resources are accessible from http://git-scm.com/
including full documentation and Git related tools.
The user discussion and development of Git take place on the Git
mailing list -- everyone is welcome to post bug reports, feature
requests, comments and patches to git@vger.kernel.org (read
Documentation/SubmittingPatches for instructions on patch submission).
To subscribe to the list, send an email with just "subscribe git" in
the body to majordomo@vger.kernel.org. The mailing list archives are
available at http://news.gmane.org/gmane.comp.version-control.git/,
http://marc.info/?l=git and other archival sites.
The maintainer frequently sends the "What's cooking" reports that
list the current status of various development topics to the mailing
list. The discussion following them give a good reference for
project status, development direction and remaining tasks.