49de321698
Factor out pre context line handling into the new function show_pre_context() and change the algorithm to rewind by looking for newline characters and roll forward again, instead of maintaining an array of line beginnings and ends. This is slower for hits, but the cost for non-matching lines becomes zero. Normally, there are far more non-matching lines, so the time spent in total decreases. Before this patch (current Linux kernel repo, best of five runs): $ time git grep --no-ext-grep -B1 memset >/dev/null real 0m2.134s user 0m1.932s sys 0m0.196s $ time git grep --no-ext-grep -B1000 memset >/dev/null real 0m12.059s user 0m11.837s sys 0m0.224s The same with this patch: $ time git grep --no-ext-grep -B1 memset >/dev/null real 0m2.117s user 0m1.892s sys 0m0.228s $ time git grep --no-ext-grep -B1000 memset >/dev/null real 0m2.986s user 0m2.696s sys 0m0.288s Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx> 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.
It was originally written by Linus Torvalds with help of a group of
hackers around the net. It is currently maintained by Junio C Hamano.
Please read the file INSTALL for installation instructions.
See Documentation/gittutorial.txt to get started, then see
Documentation/everyday.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.or.cz/
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. 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://marc.theaimsgroup.com/?l=git and other archival sites.
The messages titled "A note from the maintainer", "What's in
git.git (stable)" and "What's cooking in git.git (topics)" and
the discussion following them on the mailing list give a good
reference for project status, development direction and
remaining tasks.