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ef49a7a012
The size of objects we read from the repository and data we try to put into the repository are represented in "unsigned long", so that on larger architectures we can handle objects that weigh more than 4GB. But the interface defined in zlib.h to communicate with inflate/deflate limits avail_in (how many bytes of input are we calling zlib with) and avail_out (how many bytes of output from zlib are we ready to accept) fields effectively to 4GB by defining their type to be uInt. In many places in our code, we allocate a large buffer (e.g. mmap'ing a large loose object file) and tell zlib its size by assigning the size to avail_in field of the stream, but that will truncate the high octets of the real size. The worst part of this story is that we often pass around z_stream (the state object used by zlib) to keep track of the number of used bytes in input/output buffer by inspecting these two fields, which practically limits our callchain to the same 4GB limit. Wrap z_stream in another structure git_zstream that can express avail_in and avail_out in unsigned long. For now, just die() when the caller gives a size that cannot be given to a single zlib call. In later patches in the series, we would make git_inflate() and git_deflate() internally loop to give callers an illusion that our "improved" version of zlib interface can operate on a buffer larger than 4GB in one go. 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.