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Elijah Newren 434e0636db sequencer: do not export GIT_DIR and GIT_WORK_TREE for 'exec'
Commands executed from `git rebase --exec` can give different behavior
from within that environment than they would outside of it, due to the
fact that sequencer.c exports both GIT_DIR and GIT_WORK_TREE.  For
example, if the relevant script calls something like

  git -C ../otherdir log --format=%H --no-walk

the user may be surprised to find that the command above does not show a
commit hash from ../otherdir, because $GIT_DIR prevents automatic gitdir
detection and makes the -C option useless.

This is a regression in behavior from the original legacy
implemented-in-shell rebase.  It is perhaps rare for it to cause
problems in practice, especially since most small problems that were
caused by this area of bugs has been fixed-up in the past in a way that
masked the particular bug observed without fixing the real underlying
problem.

An explanation of how we arrived at the current situation is perhaps
merited.  The setting of GIT_DIR and GIT_WORK_TREE done by sequencer.c
arose from a sequence of historical accidents:

* When rebase was implemented as a shell command, it would call
  git-sh-setup, which among other things would set GIT_DIR -- but not
  export it.  This meant that when rebase --exec commands were run via
      /bin/sh -c "$COMMAND"
  they would not inherit the GIT_DIR setting.  The fact that GIT_DIR
  was not set in the run $COMMAND is the behavior we'd like to restore.

* When the rebase--helper builtin was introduced to allow incrementally
  replacing shell with C code, we had an implementation that was half
  shell, half C.  In particular, commit 18633e1a22 ("rebase -i: use the
  rebase--helper builtin", 2017-02-09) added calls to
      exec git rebase--helper ...
  which caused rebase--helper to inherit the GIT_DIR environment
  variable from the shell.  git's setup would change the environment
  variable from an absolute path to a relative one (".git"), but would
  leave it set.  This meant that when rebase --exec commands were run
  via
      run_command_v_opt(...)
  they would inherit the GIT_DIR setting.

* In commit 09d7b6c6fa ("sequencer: pass absolute GIT_DIR to exec
  commands", 2017-10-31), it was noted that the GIT_DIR caused problems
  with some commands; e.g.
      git rebase --exec 'cd subdir && git describe' ...
  would have GIT_DIR=.git which was invalid due to the change to the
  subdirectory.  Instead of questioning why GIT_DIR was set, that commit
  instead made sequencer change GIT_DIR to be an absolute path and
  explicitly export it via
      argv_array_pushf(&child_env, "GIT_DIR=%s", absolute_path(get_git_dir()));
      run_command_v_opt_cd_env(..., child_env.argv)

* In commit ab5e67d751 ("sequencer: pass absolute GIT_WORK_TREE to exec
  commands", 2018-07-14), it was noted that when GIT_DIR is set but
  GIT_WORK_TREE is not, that we do not discover GIT_WORK_TREE but just
  assume it is '.'.  That is incorrect if trying to run commands from a
  subdirectory.  However, rather than question why GIT_DIR was set, that
  commit instead also added GIT_WORK_TREE to the list of things to
  export.

Each of the above problems would have been fixed automatically when
git-rebase became a full builtin, had it not been for the fact that
sequencer.c started exporting GIT_DIR and GIT_WORK_TREE in the interim.
Stop exporting them now.

Signed-off-by: Elijah Newren <newren@gmail.com>
Acked-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Acked-by: Johannes Altmanninger <aclopte@gmail.com>
Acked-by: Phillip Wood <phillip.wood123@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-12-04 23:41:05 -08:00
.github Merge branch 'js/windows-ci-path-fix' 2021-10-18 15:47:58 -07:00
block-sha1
builtin Merge branch 'ev/pull-already-up-to-date-is-noop' into maint 2021-11-23 14:48:04 -08:00
ci Merge branch 'cb/ci-build-pedantic' into maint 2021-10-12 13:51:31 -07:00
compat simple-ipc: work around issues with Cygwin's Unix socket emulation 2021-11-10 09:12:19 -08:00
contrib Merge branch 're/completion-fix-test-equality' 2021-10-29 15:43:16 -07:00
Documentation Git 2.34.1 2021-11-24 10:55:13 -08:00
ewah
git-gui
gitk-git
gitweb
mergetools mergetools/xxdiff: prevent segfaults from stopping difftool 2021-10-13 11:04:04 -07:00
negotiator
perl
po l10n: pl: 2.34.0 round 3 2021-11-14 15:19:23 +01:00
ppc
refs Merge branch 'jt/no-abuse-alternate-odb-for-submodules' 2021-10-25 16:06:56 -07:00
sha1collisiondetection@855827c583
sha1dc
sha256
t sequencer: do not export GIT_DIR and GIT_WORK_TREE for 'exec' 2021-12-04 23:41:05 -08:00
templates
trace2 Merge branch 'js/trace2-raise-format-version' 2021-11-12 15:29:25 -08:00
xdiff
.cirrus.yml
.clang-format
.editorconfig
.gitattributes
.gitignore Merge branch 'js/retire-preserve-merges' 2021-10-18 15:47:56 -07:00
.gitmodules
.mailmap
.travis.yml
.tsan-suppressions
abspath.c
aclocal.m4
add-interactive.c
add-interactive.h
add-patch.c
advice.c Merge branch 'ds/add-rm-with-sparse-index' 2021-10-13 15:15:56 -07:00
advice.h Merge branch 'en/pull-conflicting-options' into maint 2021-10-12 13:51:36 -07:00
alias.c
alias.h
alloc.c
alloc.h
apply.c Merge branch 'jc/trivial-threeway-binary-merge' into maint 2021-10-12 13:51:45 -07:00
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 Merge branch 'pw/sparse-cache-tree-verify-fix' 2021-10-25 16:06:57 -07:00
cache-tree.h
cache.h Merge branch 'ab/fix-commit-error-message-upon-unwritable-object-store' 2021-10-25 16:06:57 -07:00
cbtree.c
cbtree.h
chdir-notify.c
chdir-notify.h
check-builtins.sh
checkout.c
checkout.h
chunk-format.c
chunk-format.h
CODE_OF_CONDUCT.md
color.c
color.h
column.c
column.h
combine-diff.c
command-list.txt command-list.txt: remove 'sparse-index' from main help 2021-10-25 09:10:43 -07:00
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.c: don't leak memory in handle_path_include() 2021-10-21 16:26:45 -07:00
config.h Merge branch 'ab/retire-git-config-key-is-valid' 2021-10-11 10:21:47 -07:00
config.mak.dev
config.mak.in
config.mak.uname Merge branch 'ab/config-based-hooks-1' 2021-10-13 15:15:57 -07:00
configure.ac
connect.c Merge branch 'ah/connect-parse-feature-v0-fix' into maint 2021-10-12 13:51:49 -07:00
connect.h
connected.c Merge branch 'ps/connectivity-optim' 2021-11-12 15:29:24 -08:00
connected.h
convert.c
convert.h
copy.c
COPYING
credential.c
credential.h
csum-file.c
csum-file.h
ctype.c
daemon.c Merge branch 'ab/pkt-line-cleanup' 2021-10-25 16:07:00 -07:00
date.c
decorate.c
decorate.h
delta-islands.c
delta-islands.h
delta.h
detect-compiler
diff-delta.c
diff-lib.c Merge branch 'dd/diff-files-unmerged-fix' into maint 2021-10-12 13:51:40 -07:00
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 Merge branch 'ds/add-rm-with-sparse-index' into maint 2021-11-23 14:48:11 -08:00
dir.h
editor.c Merge branch 'jc/save-restore-terminal-revert' into maint 2021-11-23 14:48:15 -08:00
entry.c
entry.h
environment.c Merge branch 'jk/ref-paranoia' 2021-10-11 10:21:47 -07:00
environment.h
exec-cmd.c
exec-cmd.h
fetch-negotiator.c
fetch-negotiator.h
fetch-pack.c
fetch-pack.h
fmt-merge-msg.c Merge branch 'fs/ssh-signing' 2021-10-25 16:06:58 -07:00
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
generate-hooklist.sh
gettext.c
gettext.h
git-add--interactive.perl
git-archimport.perl
git-bisect.sh
git-compat-util.h wrapper: remove xunsetenv() 2021-10-29 14:59:29 -07:00
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-request-pull.sh
git-send-email.perl Merge branch 'ab/send-email-config-fix' into maint 2021-10-12 13:51:44 -07:00
git-sh-i18n.sh git-sh-i18n: remove unused eval_ngettext() 2021-10-21 16:04:29 -07:00
git-sh-setup.sh git-sh-setup: remove messaging supporting --preserve-merges 2021-10-21 16:04:29 -07:00
git-submodule.sh
git-svn.perl
GIT-VERSION-GEN Git 2.34.1 2021-11-24 10:55:13 -08:00
git-web--browse.sh
git.c Merge branch 'js/retire-preserve-merges' 2021-10-18 15:47:56 -07:00
git.rc
gpg-interface.c Merge branch 'jx/message-fixes' 2021-11-03 13:32:28 -07:00
gpg-interface.h
graph.c
graph.h
grep.c Revert "grep/pcre2: fix an edge case concerning ascii patterns and UTF-8 data" 2021-11-19 09:10:27 -08:00
grep.h Merge branch 'hm/paint-hits-in-log-grep' 2021-11-01 13:48:08 -07:00
hash-lookup.c
hash-lookup.h
hash.h
hashmap.c
hashmap.h
help.c
help.h
hex.c
hook.c
hook.h
http-backend.c http-backend: remove a duplicated code branch 2021-10-25 08:56:01 -07:00
http-fetch.c
http-push.c
http-walker.c
http.c Merge branch 'ab/designated-initializers-more' 2021-10-18 15:47:57 -07:00
http.h
ident.c
imap-send.c
INSTALL
iterator.h
json-writer.c
json-writer.h
khash.h
kwset.c
kwset.h
levenshtein.c
levenshtein.h
LGPL-2.1
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 Merge branch 'fs/ssh-signing' 2021-10-25 16:06:58 -07:00
log-tree.h
ls-refs.c Merge branch 'jk/ref-paranoia' 2021-10-11 10:21:47 -07:00
ls-refs.h
mailinfo.c
mailinfo.h
mailmap.c Merge branch 'ab/mailmap-leakfix' into maint 2021-10-12 13:51:30 -07:00
mailmap.h
Makefile Merge branch 'ab/make-sparse-for-real' 2021-10-29 15:43:12 -07:00
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 branch 'jt/no-abuse-alternate-odb-for-submodules' 2021-10-25 16:06:56 -07:00
merge-ort.h
merge-recursive.c Merge branch 'jt/no-abuse-alternate-odb-for-submodules' 2021-10-25 16:06:56 -07:00
merge-recursive.h
merge.c
mergesort.c
mergesort.h
midx.c Merge branch 'tb/repack-write-midx' 2021-10-18 15:47:57 -07:00
midx.h Merge branch 'tb/repack-write-midx' 2021-10-18 15:47:57 -07:00
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 Merge branch 'ab/fsck-unexpected-type' 2021-11-12 15:29:25 -08:00
object-name.c
object-store.h Merge branch 'ab/fix-commit-error-message-upon-unwritable-object-store' 2021-10-25 16:06:57 -07:00
object.c Merge branch 'ab/fsck-unexpected-type' 2021-10-25 16:06:56 -07:00
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 Merge branch 'tb/repack-write-midx' 2021-10-18 15:47:57 -07:00
pack-bitmap.h Merge branch 'tb/repack-write-midx' 2021-10-18 15:47:57 -07:00
pack-check.c Merge branch 'ab/fsck-unexpected-type' 2021-10-25 16:06:56 -07:00
pack-objects.c
pack-objects.h
pack-revindex.c
pack-revindex.h
pack-write.c Merge branch 'tb/pack-finalize-ordering' into maint 2021-10-12 13:51:46 -07:00
pack.h
packfile.c Merge branch 'rs/close-pack-leakfix' 2021-10-03 21:49:20 -07:00
packfile.h
pager.c
parallel-checkout.c pkt-line.[ch]: remove unused packet_read_line_buf() 2021-10-15 13:09:40 -07:00
parallel-checkout.h
parse-options-cb.c
parse-options.c Merge branch 'ab/parse-options-cleanup' 2021-11-09 13:19:06 -08:00
parse-options.h Merge branch 'ab/parse-options-cleanup' 2021-11-09 13:19:06 -08:00
patch-delta.c
patch-ids.c
patch-ids.h
path.c
path.h
pathspec.c
pathspec.h
pkt-line.c Merge branch 'ab/pkt-line-cleanup' 2021-10-25 16:07:00 -07:00
pkt-line.h Merge branch 'ab/pkt-line-cleanup' 2021-10-25 16:07:00 -07:00
preload-index.c
pretty.c Merge branch 'hm/paint-hits-in-log-grep' 2021-11-01 13:48:08 -07:00
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 ref-filter: --format=%(raw) support --perl 2021-07-26 12:01:25 -07:00
quote.h
range-diff.c Merge branch 'rs/range-diff-avoid-segfault-with-I' into maint 2021-10-12 13:51:45 -07:00
range-diff.h
reachable.c
reachable.h
read-cache.c Merge branch 'rs/add-dry-run-without-objects' 2021-10-25 16:06:57 -07:00
README.md
rebase-interactive.c
rebase-interactive.h
rebase.c
rebase.h
ref-filter.c i18n: fix typos found during l10n for git 2.34.0 2021-10-31 22:49:49 -07:00
ref-filter.h ref-filter API user: add and use a ref_sorting_release() 2021-10-20 11:36:13 -07:00
reflog-walk.c
reflog-walk.h
refs.c Merge branch 'jt/no-abuse-alternate-odb-for-submodules' 2021-10-25 16:06:56 -07:00
refs.h Merge branch 'jk/ref-paranoia' 2021-10-11 10:21:47 -07:00
refspec.c
refspec.h
RelNotes Git 2.34.1 2021-11-24 10:55:13 -08:00
remote-curl.c Merge branch 'ab/pkt-line-cleanup' 2021-10-25 16:07:00 -07:00
remote.c
remote.h
replace-object.c
replace-object.h
repo-settings.c
repository.c Merge branch 'jt/add-submodule-odb-clean-up' 2021-10-06 13:40:11 -07:00
repository.h Merge branch 'ab/repo-settings-cleanup' 2021-10-06 13:40:11 -07:00
rerere.c
rerere.h
reset.c
reset.h
resolve-undo.c
resolve-undo.h
revision.c Merge branch 'ps/connectivity-optim' 2021-11-12 15:29:24 -08:00
revision.h Merge branch 'jt/add-submodule-odb-clean-up' 2021-10-06 13:40:11 -07:00
run-command.c Merge branch 'vd/pthread-setspecific-g11-fix' into maint 2021-11-04 12:24:20 -07:00
run-command.h Merge branch 'jh/builtin-fsmonitor-part1' 2021-10-13 15:15:58 -07:00
SECURITY.md
send-pack.c Merge branch 'fs/ssh-signing' 2021-10-25 16:06:58 -07:00
send-pack.h
sequencer.c sequencer: do not export GIT_DIR and GIT_WORK_TREE for 'exec' 2021-12-04 23:41:05 -08:00
sequencer.h Merge branch 'js/retire-preserve-merges' 2021-10-18 15:47:56 -07:00
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 Merge branch 'jh/builtin-fsmonitor-part1' 2021-10-13 15:15:58 -07:00
sparse-index.c
sparse-index.h
split-index.c
split-index.h
stable-qsort.c
strbuf.c merge-{ort,recursive}: remove add_submodule_odb() 2021-10-08 15:06:06 -07:00
strbuf.h Merge branch 'jt/no-abuse-alternate-odb-for-submodules' 2021-10-25 16:06:56 -07:00
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 Merge branch 'jt/no-abuse-alternate-odb-for-submodules' 2021-10-25 16:06:56 -07:00
submodule.h
symlinks.c
tag.c
tag.h
tar.h
tempfile.c
tempfile.h
thread-utils.c thread-utils: macros to unconditionally compile pthreads API 2018-10-29 11:22:48 +09:00
thread-utils.h
tmp-objdir.c
tmp-objdir.h
trace2.c
trace2.h Merge branch 'jh/builtin-fsmonitor-part1' 2021-10-13 15:15:58 -07:00
trace.c
trace.h
trailer.c
trailer.h
transport-helper.c Merge branch 'jk/http-push-status-fix' 2021-10-29 15:43:12 -07:00
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 Merge branch 'ab/unpack-trees-leakfix' 2021-10-25 16:06:56 -07:00
unpack-trees.h
upload-pack.c
upload-pack.h
url.c
url.h
urlmatch.c
urlmatch.h
usage.c
userdiff.c userdiff-cpp: back out the digit-separators in numbers 2021-10-25 08:47:44 -07:00
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 wrapper: remove xunsetenv() 2021-10-29 14:59:29 -07:00
write-or-die.c
ws.c
wt-status.c
wt-status.h
xdiff-interface.c
xdiff-interface.h
zlib.c

Build status

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>.

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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