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8f41c07f90
estimate_cache_size() tries to guess how much memory is needed for the in-memory representation of an index file. It does that by using the file size, the number of entries and the difference of the sizes of the on-disk and in-memory structs -- without having to check the length of the name of each entry, which varies for each entry, but their sums are the same no matter the representation. Except there can be a difference. First of all, the size is really calculated by ce_size and ondisk_ce_size based on offsetof(..., name), not sizeof, which can be different. And entries are padded with 1 to 8 NULs at the end (after the variable name) to make their total length a multiple of eight. So in order to allocate enough memory to hold the index, change the delta calculation to be based on offsetof(..., name) and round up to the next multiple of eight. On a 32-bit Linux, this delta was used before: sizeof(struct cache_entry) == 72 sizeof(struct ondisk_cache_entry) == 64 --- 8 The actual difference for an entry with a filename length of one was, however (find the definitions are in cache.h): offsetof(struct cache_entry, name) == 72 offsetof(struct ondisk_cache_entry, name) == 62 ce_size == (72 + 1 + 8) & ~7 == 80 ondisk_ce_size == (62 + 1 + 8) & ~7 == 64 --- 16 So eight bytes less had been allocated for such entries. The new formula yields the correct delta: (72 - 62 + 7) & ~7 == 16 Reported-by: John Hsing <tsyj2007@gmail.com> 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-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. 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.