When there are no shallow entries to write, we skip creating
the tempfile entirely and try to return the empty string.
But we do so by calling get_tempfile_path() on the inactive
tempfile object. This will trigger an assertion that kills
the program. The bug was introduced by 6e122b449b
(setup_temporary_shallow(): use tempfile module,
2015-08-10). But nobody seems to have noticed since then
because we do not end up calling this function at all when
there are no shallow items. In other words, this code path
is completely unexercised.
Since the tempfile object is a static global, it _is_
possible that we call the function twice, writing out
shallow info the first time and then "reusing" our tempfile
object the second time. But:
1. It seems unlikely that this was the intent, as hitting
this code path would imply somebody clearing the
shallow_info list between calls.
And if somebody _did_ call the function multiple times
without clearing the shallow_info list, we'd hit a
different BUG for trying to reuse an already-active
tempfile.
2. I verified by code inspection that the function is only
called once per program. And also replacing this code
with a BUG() and running the test suite demonstrates
that it is not triggered there.
So we could probably just replace this with an assertion and
confirm that it's never called. However, the original intent
does seem to be that you _could_ call it when the
shallow_info is empty. And that's easy enough to do; since
the return value doesn't need to point to a writable buffer,
we can just return a string literal.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git - fast, scalable, distributed revision control system
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.
Many Git online resources are accessible from https://git-scm.com/ including full documentation and Git related tools.
See Documentation/gittutorial.txt to get started, then see
Documentation/giteveryday.txt for a useful minimum set of commands, and
Documentation/git-.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).
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 https://public-inbox.org/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.
The name "git" was given by Linus Torvalds when he wrote the very first version. He described the tool as "the stupid content tracker" and the name as (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