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e426311bef
Since b19138b (git-svn: Make it incrementally faster by minimizing temp files, v1.6.0), git-svn has been using the Git.pm temp_acquire and temp_release mechanism to avoid unnecessary temp file churn and provide a speed boost. However, that change introduced a call to temp_acquire inside the Git::SVN::Fetcher::close_file function for an 'svn_hash' temp file. Because an SVN::Pool is active at the time this function is called, if the Git::temp_acquire function ends up actually creating a new FileHandle for the temp file (which it will the first time it's called with the name 'svn_hash') that FileHandle will end up in the SVN::Pool and should that pool have SVN::Pool::clear called on it that FileHandle will be closed out from under Git::temp_acquire. Since the only call site to Git::temp_acquire with the name 'svn_hash' is inside the close_file function, if an 'svn_hash' temp file is ever created its FileHandle is guaranteed to be created in the active SVN::Pool. This has not been a problem in the past because the SVN::Pool was not being cleared. However, since dfa72fdb (git-svn: reload RA every log-window-size, v2.2.0) the pool has been getting cleared periodically at which point the FileHandle for the 'svn_hash' temp file gets closed. Any subsequent calls to Git::temp_acquire for 'svn_hash', however, succeed without creating/opening a new temporary file since it still has the now invalid FileHandle in its cache. Callers that then attempt to use that FileHandle fail with an error. We avoid this problem by making sure the 'svn_hash' temp file is created in the same place the 'svn_delta_...' and 'git_blob_...' temp files are (and then temp_release'd) so that it can be safely used inside the close_file function without having its FileHandle end up in an SVN::Pool that gets cleared. Additionally the Git.pm cat_blob function creates a bidirectional pipe FileHandle using the IPC::Open2::open2 function. If that handle is created too late, it also gets caught up in the SVN::Pool and incorrectly closed by the SVN::Pool::clear call. But this only seems to happen with more recent versions of Perl and svn. To avoid this problem we add an explicit call to _open_cat_blob_if_needed before the first call to SVN::Pool->new_default to make sure the open2 handle does not end up in the SVN::Pool. Signed-off-by: Kyle J. McKay <mackyle@gmail.com> Signed-off-by: Eric Wong <normalperson@yhbt.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.