![]() The original point of the GIT_REF_PARANOIA flag was to include broken refs in iterations, so that possibly-destructive operations would not silently ignore them (and would generally instead try to operate on the oids and fail when the objects could not be accessed). We already turned this on by default for some dangerous operations, like "repack -ad" (where missing a reachability tip would mean dropping the associated history). But it was not on for general use, even though it could easily result in the spreading of corruption (e.g., imagine cloning a repository which simply omits some of its refs because their objects are missing; the result quietly succeeds even though you did not clone everything!). This patch turns on GIT_REF_PARANOIA by default. So a clone as mentioned above would actually fail (upload-pack tells us about the broken ref, and when we ask for the objects, pack-objects fails to deliver them). This may be inconvenient when working with a corrupted repository, but: - we are better off to err on the side of complaining about corruption, and then provide mechanisms for explicitly loosening safety. - this is only one type of corruption anyway. If we are missing any other objects in the history that _aren't_ ref tips, then we'd behave similarly (happily show the ref, but then barf when we started traversing). We retain the GIT_REF_PARANOIA variable, but simply default it to "1" instead of "0". That gives the user an escape hatch for loosening this when working with a corrupt repository. It won't work across a remote connection to upload-pack (because we can't necessarily set environment variables on the remote), but there the client has other options (e.g., choosing which refs to fetch). As a bonus, this also makes ref iteration faster in general (because we don't have to call has_object_file() for each ref), though probably not noticeably so in the general case. In a repo with a million refs, it shaved a few hundred milliseconds off of upload-pack's advertisement; that's noticeable, but most repos are not nearly that large. The possible downside here is that any operation which iterates refs but doesn't ever open their objects may now quietly claim to have X when the object is corrupted (e.g., "git rev-list new-branch --not --all" will treat a broken ref as uninteresting). But again, that's not really any different than corruption below the ref level. We might have refs/heads/old-branch as non-corrupt, but we are not actively checking that we have the entire reachable history. Or the pointed-to object could even be corrupted on-disk (but our "do we have it" check would still succeed). In that sense, this is merely bringing ref-corruption in line with general object corruption. One alternative implementation would be to actually check for broken refs, and then _immediately die_ if we see any. That would cause the "rev-list --not --all" case above to abort immediately. But in many ways that's the worst of all worlds: - it still spends time looking up the objects an extra time - it still doesn't catch corruption below the ref level - it's even more inconvenient; with the current implementation of GIT_REF_PARANOIA for something like upload-pack, we can make the advertisement and let the client choose a non-broken piece of history. If we bail as soon as we see a broken ref, they cannot even see the advertisement. The test changes here show some of the fallout. A non-destructive "git repack -adk" now fails by default (but we can override it). Deleting a broken ref now actually tells the hooks the correct "before" state, rather than a confusing null oid. Signed-off-by: Jeff King <peff@peff.net> Reviewed-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com> |
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Documentation | ||
block-sha1 | ||
builtin | ||
ci | ||
compat | ||
contrib | ||
ewah | ||
git-gui | ||
gitk-git | ||
gitweb | ||
mergetools | ||
negotiator | ||
perl | ||
po | ||
ppc | ||
refs | ||
sha1collisiondetection@855827c583 | ||
sha1dc | ||
sha256 | ||
t | ||
templates | ||
trace2 | ||
xdiff | ||
.cirrus.yml | ||
.clang-format | ||
.editorconfig | ||
.gitattributes | ||
.gitignore | ||
.gitmodules | ||
.mailmap | ||
.travis.yml | ||
.tsan-suppressions | ||
CODE_OF_CONDUCT.md | ||
COPYING | ||
GIT-VERSION-GEN | ||
INSTALL | ||
LGPL-2.1 | ||
Makefile | ||
README.md | ||
RelNotes | ||
SECURITY.md | ||
abspath.c | ||
aclocal.m4 | ||
add-interactive.c | ||
add-interactive.h | ||
add-patch.c | ||
advice.c | ||
advice.h | ||
alias.c | ||
alias.h | ||
alloc.c | ||
alloc.h | ||
apply.c | ||
apply.h | ||
archive-tar.c | ||
archive-zip.c | ||
archive.c | ||
archive.h | ||
attr.c | ||
attr.h | ||
banned.h | ||
base85.c | ||
bisect.c | ||
bisect.h | ||
blame.c | ||
blame.h | ||
blob.c | ||
blob.h | ||
bloom.c | ||
bloom.h | ||
branch.c | ||
branch.h | ||
builtin.h | ||
bulk-checkin.c | ||
bulk-checkin.h | ||
bundle.c | ||
bundle.h | ||
cache-tree.c | ||
cache-tree.h | ||
cache.h | ||
cbtree.c | ||
cbtree.h | ||
chdir-notify.c | ||
chdir-notify.h | ||
check-builtins.sh | ||
checkout.c | ||
checkout.h | ||
chunk-format.c | ||
chunk-format.h | ||
color.c | ||
color.h | ||
column.c | ||
column.h | ||
combine-diff.c | ||
command-list.txt | ||
commit-graph.c | ||
commit-graph.h | ||
commit-reach.c | ||
commit-reach.h | ||
commit-slab-decl.h | ||
commit-slab-impl.h | ||
commit-slab.h | ||
commit.c | ||
commit.h | ||
common-main.c | ||
config.c | ||
config.h | ||
config.mak.dev | ||
config.mak.in | ||
config.mak.uname | ||
configure.ac | ||
connect.c | ||
connect.h | ||
connected.c | ||
connected.h | ||
convert.c | ||
convert.h | ||
copy.c | ||
credential.c | ||
credential.h | ||
csum-file.c | ||
csum-file.h | ||
ctype.c | ||
daemon.c | ||
date.c | ||
decorate.c | ||
decorate.h | ||
delta-islands.c | ||
delta-islands.h | ||
delta.h | ||
detect-compiler | ||
diff-delta.c | ||
diff-lib.c | ||
diff-merges.c | ||
diff-merges.h | ||
diff-no-index.c | ||
diff.c | ||
diff.h | ||
diffcore-break.c | ||
diffcore-delta.c | ||
diffcore-order.c | ||
diffcore-pickaxe.c | ||
diffcore-rename.c | ||
diffcore-rotate.c | ||
diffcore.h | ||
dir-iterator.c | ||
dir-iterator.h | ||
dir.c | ||
dir.h | ||
editor.c | ||
entry.c | ||
entry.h | ||
environment.c | ||
environment.h | ||
exec-cmd.c | ||
exec-cmd.h | ||
fetch-negotiator.c | ||
fetch-negotiator.h | ||
fetch-pack.c | ||
fetch-pack.h | ||
fmt-merge-msg.c | ||
fmt-merge-msg.h | ||
fsck.c | ||
fsck.h | ||
fsmonitor.c | ||
fsmonitor.h | ||
fuzz-commit-graph.c | ||
fuzz-pack-headers.c | ||
fuzz-pack-idx.c | ||
generate-cmdlist.sh | ||
generate-configlist.sh | ||
gettext.c | ||
gettext.h | ||
git-add--interactive.perl | ||
git-archimport.perl | ||
git-bisect.sh | ||
git-compat-util.h | ||
git-curl-compat.h | ||
git-cvsexportcommit.perl | ||
git-cvsimport.perl | ||
git-cvsserver.perl | ||
git-difftool--helper.sh | ||
git-filter-branch.sh | ||
git-instaweb.sh | ||
git-merge-octopus.sh | ||
git-merge-one-file.sh | ||
git-merge-resolve.sh | ||
git-mergetool--lib.sh | ||
git-mergetool.sh | ||
git-p4.py | ||
git-quiltimport.sh | ||
git-rebase--preserve-merges.sh | ||
git-request-pull.sh | ||
git-send-email.perl | ||
git-sh-i18n.sh | ||
git-sh-setup.sh | ||
git-submodule.sh | ||
git-svn.perl | ||
git-web--browse.sh | ||
git.c | ||
git.rc | ||
gpg-interface.c | ||
gpg-interface.h | ||
graph.c | ||
graph.h | ||
grep.c | ||
grep.h | ||
hash-lookup.c | ||
hash-lookup.h | ||
hash.h | ||
hashmap.c | ||
hashmap.h | ||
help.c | ||
help.h | ||
hex.c | ||
http-backend.c | ||
http-fetch.c | ||
http-push.c | ||
http-walker.c | ||
http.c | ||
http.h | ||
ident.c | ||
imap-send.c | ||
iterator.h | ||
json-writer.c | ||
json-writer.h | ||
khash.h | ||
kwset.c | ||
kwset.h | ||
levenshtein.c | ||
levenshtein.h | ||
line-log.c | ||
line-log.h | ||
line-range.c | ||
line-range.h | ||
linear-assignment.c | ||
linear-assignment.h | ||
list-objects-filter-options.c | ||
list-objects-filter-options.h | ||
list-objects-filter.c | ||
list-objects-filter.h | ||
list-objects.c | ||
list-objects.h | ||
list.h | ||
ll-merge.c | ||
ll-merge.h | ||
lockfile.c | ||
lockfile.h | ||
log-tree.c | ||
log-tree.h | ||
ls-refs.c | ||
ls-refs.h | ||
mailinfo.c | ||
mailinfo.h | ||
mailmap.c | ||
mailmap.h | ||
match-trees.c | ||
mem-pool.c | ||
mem-pool.h | ||
merge-blobs.c | ||
merge-blobs.h | ||
merge-ort-wrappers.c | ||
merge-ort-wrappers.h | ||
merge-ort.c | ||
merge-ort.h | ||
merge-recursive.c | ||
merge-recursive.h | ||
merge.c | ||
mergesort.c | ||
mergesort.h | ||
midx.c | ||
midx.h | ||
name-hash.c | ||
notes-cache.c | ||
notes-cache.h | ||
notes-merge.c | ||
notes-merge.h | ||
notes-utils.c | ||
notes-utils.h | ||
notes.c | ||
notes.h | ||
object-file.c | ||
object-name.c | ||
object-store.h | ||
object.c | ||
object.h | ||
oid-array.c | ||
oid-array.h | ||
oidmap.c | ||
oidmap.h | ||
oidset.c | ||
oidset.h | ||
oidtree.c | ||
oidtree.h | ||
pack-bitmap-write.c | ||
pack-bitmap.c | ||
pack-bitmap.h | ||
pack-check.c | ||
pack-objects.c | ||
pack-objects.h | ||
pack-revindex.c | ||
pack-revindex.h | ||
pack-write.c | ||
pack.h | ||
packfile.c | ||
packfile.h | ||
pager.c | ||
parallel-checkout.c | ||
parallel-checkout.h | ||
parse-options-cb.c | ||
parse-options.c | ||
parse-options.h | ||
patch-delta.c | ||
patch-ids.c | ||
patch-ids.h | ||
path.c | ||
path.h | ||
pathspec.c | ||
pathspec.h | ||
pkt-line.c | ||
pkt-line.h | ||
preload-index.c | ||
pretty.c | ||
pretty.h | ||
prio-queue.c | ||
prio-queue.h | ||
progress.c | ||
progress.h | ||
promisor-remote.c | ||
promisor-remote.h | ||
prompt.c | ||
prompt.h | ||
protocol-caps.c | ||
protocol-caps.h | ||
protocol.c | ||
protocol.h | ||
prune-packed.c | ||
prune-packed.h | ||
quote.c | ||
quote.h | ||
range-diff.c | ||
range-diff.h | ||
reachable.c | ||
reachable.h | ||
read-cache.c | ||
rebase-interactive.c | ||
rebase-interactive.h | ||
rebase.c | ||
rebase.h | ||
ref-filter.c | ||
ref-filter.h | ||
reflog-walk.c | ||
reflog-walk.h | ||
refs.c | ||
refs.h | ||
refspec.c | ||
refspec.h | ||
remote-curl.c | ||
remote.c | ||
remote.h | ||
replace-object.c | ||
replace-object.h | ||
repo-settings.c | ||
repository.c | ||
repository.h | ||
rerere.c | ||
rerere.h | ||
reset.c | ||
reset.h | ||
resolve-undo.c | ||
resolve-undo.h | ||
revision.c | ||
revision.h | ||
run-command.c | ||
run-command.h | ||
send-pack.c | ||
send-pack.h | ||
sequencer.c | ||
sequencer.h | ||
serve.c | ||
serve.h | ||
server-info.c | ||
setup.c | ||
sh-i18n--envsubst.c | ||
sha1dc_git.c | ||
sha1dc_git.h | ||
shallow.c | ||
shallow.h | ||
shell.c | ||
shortlog.h | ||
sideband.c | ||
sideband.h | ||
sigchain.c | ||
sigchain.h | ||
simple-ipc.h | ||
sparse-index.c | ||
sparse-index.h | ||
split-index.c | ||
split-index.h | ||
stable-qsort.c | ||
strbuf.c | ||
strbuf.h | ||
streaming.c | ||
streaming.h | ||
string-list.c | ||
string-list.h | ||
strmap.c | ||
strmap.h | ||
strvec.c | ||
strvec.h | ||
sub-process.c | ||
sub-process.h | ||
submodule-config.c | ||
submodule-config.h | ||
submodule.c | ||
submodule.h | ||
symlinks.c | ||
tag.c | ||
tag.h | ||
tar.h | ||
tempfile.c | ||
tempfile.h | ||
thread-utils.c | ||
thread-utils.h | ||
tmp-objdir.c | ||
tmp-objdir.h | ||
trace.c | ||
trace.h | ||
trace2.c | ||
trace2.h | ||
trailer.c | ||
trailer.h | ||
transport-helper.c | ||
transport-internal.h | ||
transport.c | ||
transport.h | ||
tree-diff.c | ||
tree-walk.c | ||
tree-walk.h | ||
tree.c | ||
tree.h | ||
unicode-width.h | ||
unimplemented.sh | ||
unix-socket.c | ||
unix-socket.h | ||
unix-stream-server.c | ||
unix-stream-server.h | ||
unpack-trees.c | ||
unpack-trees.h | ||
upload-pack.c | ||
upload-pack.h | ||
url.c | ||
url.h | ||
urlmatch.c | ||
urlmatch.h | ||
usage.c | ||
userdiff.c | ||
userdiff.h | ||
utf8.c | ||
utf8.h | ||
varint.c | ||
varint.h | ||
version.c | ||
version.h | ||
versioncmp.c | ||
walker.c | ||
walker.h | ||
wildmatch.c | ||
wildmatch.h | ||
worktree.c | ||
worktree.h | ||
wrap-for-bin.sh | ||
wrapper.c | ||
write-or-die.c | ||
ws.c | ||
wt-status.c | ||
wt-status.h | ||
xdiff-interface.c | ||
xdiff-interface.h | ||
zlib.c |
README.md
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-<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).
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://lore.kernel.org/git/, http://marc.info/?l=git and other archival sites.
Issues which are security relevant should be disclosed privately to the Git Security mailing list git-security@googlegroups.com.
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