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James Coglan d62893ecc1 graph: commit and post-merge lines for left-skewed merges
Following the introduction of "left-skewed" merges, which are merges
whose first parent fuses with another edge to its left, we have some
more edge cases to deal with in the display of commit and post-merge
lines.

The current graph code handles the following cases for edges appearing
to the right of the commit (*) on commit lines. A 2-way merge is usually
followed by vertical lines:

        | | |
        | * |
        | |\ \

An octopus merge (more than two parents) is always followed by edges
sloping to the right:

        | |  \          | |    \
        | *-. \         | *---. \
        | |\ \ \        | |\ \ \ \

A 2-way merge is followed by a right-sloping edge if the commit line
immediately follows a post-merge line for a commit that appears in the
same column as the current commit, or any column to the left of that:

        | *             | * |
        | |\            | |\ \
        | * \           | | * \
        | |\ \          | | |\ \

This commit introduces the following new cases for commit lines. If a
2-way merge skews to the left, then the edges to its right are always
vertical lines, even if the commit follows a post-merge line:

        | | |           | |\
        | * |           | * |
        |/| |           |/| |

A commit with 3 parents that skews left is followed by vertical edges:

        | | |
        | * |
        |/|\ \

If a 3-way left-skewed merge commit appears immediately after a
post-merge line, then it may be followed the right-sloping edges, just
like a 2-way merge that is not skewed.

        | |\
        | * \
        |/|\ \

Octopus merges with 4 or more parents that skew to the left will always
be followed by right-sloping edges, because the existing columns need to
expand around the merge.

        | |  \
        | *-. \
        |/|\ \ \

On post-merge lines, usually all edges following the current commit
slope to the right:

        | * | |
        | |\ \ \

However, if the commit is a left-skewed 2-way merge, the edges to its
right remain vertical. We also need to display a space after the
vertical line descending from the commit marker, whereas this line would
normally be followed by a backslash.

        | * | |
        |/| | |

If a left-skewed merge has more than 2 parents, then the edges to its
right are still sloped as they bend around the edges introduced by the
merge.

        | * | |
        |/|\ \ \

To handle these new cases, we need to know not just how many parents
each commit has, but how many new columns it adds to the display; this
quantity is recorded in the `edges_added` field for the current commit,
and `prev_edges_added` field for the previous commit.

Here, "column" refers to visual columns, not the logical columns of the
`columns` array. This is because even if all the commit's parents end up
fusing with existing edges, they initially introduce distinct edges in
the commit and post-merge lines before those edges collapse. For
example, a 3-way merge whose 2nd and 3rd parents fuse with existing
edges still introduces 2 visual columns that affect the display of edges
to their right.

        | | |  \
        | | *-. \
        | | |\ \ \
        | |_|/ / /
        |/| | / /
        | | |/ /
        | |/| |
        | | | |

This merge does not introduce any *logical* columns; there are 4 edges
before and after this commit once all edges have collapsed. But it does
initially introduce 2 new edges that need to be accommodated by the
edges to their right.

Signed-off-by: James Coglan <jcoglan@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-10-16 11:11:25 +09:00
.github
block-sha1
builtin Merge branch 'js/trace2-fetch-push' 2019-10-15 13:48:03 +09:00
ci Merge branch 'dl/honor-cflags-in-hdr-check' 2019-10-07 11:33:02 +09:00
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Documentation Ninth batch 2019-10-15 13:48:04 +09:00
ewah
git-gui Merge branch 'master' of https://github.com/prati0100/git-gui 2019-09-18 11:22:11 -07:00
gitk-git Merge gitk to pick up emergency build fix 2019-09-17 14:59:18 -07:00
gitweb
mergetools
negotiator
perl git-svn: trim leading and trailing whitespaces in author name 2019-09-28 13:51:42 +09:00
po gitk: rename zh_CN.po to zh_cn.po 2019-09-17 14:58:12 -07:00
ppc
refs Merge branch 'sc/pack-refs-deletion-racefix' 2019-08-22 12:34:10 -07:00
sha1collisiondetection@855827c583
sha1dc
sha256
t graph: commit and post-merge lines for left-skewed merges 2019-10-16 11:11:25 +09:00
templates git-merge: honor pre-merge-commit hook 2019-08-07 12:37:33 -07:00
trace2 trace2: write discard message to sentinel files 2019-10-05 17:53:51 +09:00
vcs-svn
xdiff xdiffi: fix typos and touch up comments 2019-10-09 10:58:34 +09:00
.clang-format
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.gitignore Merge branch 'dl/honor-cflags-in-hdr-check' 2019-10-07 11:33:02 +09:00
.gitmodules
.mailmap .mailmap: update email address of Andrey Mazo 2019-09-20 22:21:28 -07:00
.travis.yml travis-ci: build with GCC 4.8 as well 2019-07-19 14:06:01 -07:00
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abspath.c
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advice.c
advice.h
alias.c
alias.h
alloc.c
alloc.h
apply.c Merge branch 'tg/range-diff-output-update' 2019-10-15 13:48:02 +09:00
apply.h apply.h: include missing header 2019-09-28 14:04:16 +09:00
archive-tar.c Merge branch 'rs/pax-extended-header-length-fix' 2019-09-09 12:26:37 -07:00
archive-zip.c
archive.c
archive.h
argv-array.c
argv-array.h
attr.c Merge branch 'ew/hashmap' 2019-10-15 13:48:02 +09:00
attr.h
azure-pipelines.yml Merge branch 'js/azure-pipelines-msvc' 2019-10-15 13:48:00 +09:00
banned.h banned.h: fix vsprintf()'s ban message 2019-08-26 10:32:45 -07:00
base85.c
bisect.c bisect: switch to using the_hash_algo 2019-08-19 15:04:58 -07:00
bisect.h
blame.c Merge branch 'ew/hashmap' 2019-10-15 13:48:02 +09:00
blame.h
blob.c
blob.h
branch.c
branch.h
builtin.h Merge branch 'ab/test-env' 2019-07-25 13:59:20 -07:00
bulk-checkin.c bulk-checkin: zero-initialize hashfile_checkpoint 2019-09-06 11:03:39 -07:00
bulk-checkin.h
bundle.c bundle: switch to use the_hash_algo 2019-08-19 15:04:58 -07:00
bundle.h
cache-tree.c Merge branch 'en/merge-recursive-cleanup' 2019-10-15 13:47:59 +09:00
cache-tree.h cache-tree: share code between functions writing an index as a tree 2019-08-19 10:08:03 -07:00
cache.h Merge branch 'js/azure-pipelines-msvc' 2019-10-15 13:48:00 +09:00
chdir-notify.c
chdir-notify.h
check_bindir
check-builtins.sh
checkout.c
checkout.h
CODE_OF_CONDUCT.md CODE_OF_CONDUCT: mention individual project-leader emails 2019-10-10 10:41:46 +09:00
color.c
color.h
column.c
column.h *.[ch]: manually align parameter lists 2019-05-05 15:20:10 +09:00
combine-diff.c combine-diff: replace GIT_SHA1_HEXSZ with the_hash_algo 2019-08-19 15:04:58 -07:00
command-list.txt
commit-graph.c Merge branch 'ah/cleanups' 2019-10-09 14:01:00 +09:00
commit-graph.h upload-pack: disable commit graph more gently for shallow traversal 2019-09-12 12:30:08 -07:00
commit-reach.c
commit-reach.h
commit-slab-decl.h
commit-slab-impl.h
commit-slab.h
commit.c Merge branch 'tb/commit-graph-harden' 2019-10-07 11:32:58 +09:00
commit.h
common-main.c common-main: delay trace2 initialization 2019-08-06 13:09:01 -07:00
config.c Merge branch 'ew/hashmap' 2019-10-15 13:48:02 +09:00
config.h
config.mak.dev
config.mak.in
config.mak.uname vcxproj: include more generated files 2019-10-06 09:07:44 +09:00
configure.ac
connect.c mingw: support UNC in git clone file://server/share/repo 2019-08-26 10:00:33 -07:00
connect.h
connected.c Merge branch 'bc/object-id-part17' 2019-10-11 14:24:46 +09:00
connected.h
convert.c Merge branch 'rs/convert-fix-utf-without-dash' 2019-10-09 14:01:00 +09:00
convert.h am: reload .gitattributes after patching it 2019-09-03 15:16:18 -07:00
copy.c
COPYING
credential-cache--daemon.c
credential-cache.c
credential-store.c
credential.c
credential.h
csum-file.c
csum-file.h
ctype.c
daemon.c
date.c Quit passing 'now' to date code 2019-09-12 11:03:51 -07:00
decorate.c
decorate.h
delta-islands.c
delta-islands.h
delta.h
detect-compiler
diff-delta.c diff-delta: set size out-parameter to 0 for NULL delta 2019-09-06 11:03:39 -07:00
diff-lib.c
diff-no-index.c
diff.c Merge branch 'ew/hashmap' 2019-10-15 13:48:02 +09:00
diff.h patch-id: convert to use the_hash_algo 2019-08-19 15:04:57 -07:00
diffcore-break.c diffcore-break: use a goto instead of a redundant if statement 2019-10-02 15:04:21 +09:00
diffcore-delta.c
diffcore-order.c
diffcore-pickaxe.c
diffcore-rename.c Merge branch 'ew/hashmap' 2019-10-15 13:48:02 +09:00
diffcore.h
dir-iterator.c
dir-iterator.h
dir.c Merge branch 'en/clean-nested-with-ignored' 2019-10-11 14:24:46 +09:00
dir.h Merge branch 'en/clean-nested-with-ignored' 2019-10-11 14:24:46 +09:00
editor.c
entry.c
environment.c
exec-cmd.c
exec-cmd.h
fast-import.c Merge branch 'en/fast-imexport-nested-tags' 2019-10-15 13:48:00 +09:00
fetch-negotiator.c repo-settings: create feature.experimental setting 2019-08-13 13:33:55 -07:00
fetch-negotiator.h repo-settings: create feature.experimental setting 2019-08-13 13:33:55 -07:00
fetch-pack.c Merge branch 'js/trace2-fetch-push' 2019-10-15 13:48:03 +09:00
fetch-pack.h
fmt-merge-msg.h
fsck.c
fsck.h
fsmonitor.c Merge branch 'cb/fsmonitor-intfix' into maint 2019-07-29 12:38:15 -07:00
fsmonitor.h
fuzz-commit-graph.c
fuzz-pack-headers.c
fuzz-pack-idx.c
generate-cmdlist.sh
gettext.c Merge branch 'ab/test-env' 2019-07-25 13:59:20 -07:00
gettext.h
git-add--interactive.perl add -i: show progress counter in the prompt 2019-10-04 07:12:19 +09:00
git-archimport.perl
git-bisect.sh
git-compat-util.h Merge branch 'ew/hashmap' 2019-10-15 13:48:02 +09:00
git-cvsexportcommit.perl
git-cvsimport.perl
git-cvsserver.perl
git-difftool--helper.sh
git-filter-branch.sh Recommend git-filter-repo instead of git-filter-branch 2019-09-05 13:01:48 -07:00
git-instaweb.sh
git-legacy-stash.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-p4: auto-delete named temporary file 2019-10-06 20:43:37 +09:00
git-parse-remote.sh
git-quiltimport.sh
git-rebase--preserve-merges.sh rebase: fold git-rebase--common into the -p backend 2019-07-31 12:24:06 -07:00
git-request-pull.sh
git-send-email.perl
git-sh-i18n.sh
git-sh-setup.sh
git-submodule.sh
git-svn.perl
GIT-VERSION-GEN First batch after Git 2.23 2019-08-22 12:41:04 -07:00
git-web--browse.sh
git.c git: use COPY_ARRAY and MOVE_ARRAY in handle_alias() 2019-09-20 11:11:26 -07:00
git.rc
gpg-interface.c
gpg-interface.h
graph.c graph: commit and post-merge lines for left-skewed merges 2019-10-16 11:11:25 +09:00
graph.h
grep.c Merge branch 'cb/pcre1-cleanup' 2019-10-11 14:24:47 +09:00
grep.h Merge branch 'cb/pcre1-cleanup' 2019-10-11 14:24:47 +09:00
hash.h
hashmap.c hashmap: remove type arg from hashmap_{get,put,remove}_entry 2019-10-07 10:20:12 +09:00
hashmap.h hashmap_entry: remove first member requirement from docs 2019-10-07 10:20:12 +09:00
help.c Merge branch 'rs/help-unknown-ref-does-not-return' 2019-09-30 13:19:27 +09:00
help.h help: make help_unknown_ref() NORETURN 2019-08-30 10:22:42 -07:00
hex.c
http-backend.c
http-fetch.c
http-push.c
http-walker.c
http.c Merge branch 'mh/http-urlmatch-cleanup' 2019-09-30 13:19:24 +09:00
http.h http: use xmalloc with cURL 2019-08-15 12:37:10 -07:00
ident.c
imap-send.c
INSTALL
interdiff.c
interdiff.h
iterator.h
json-writer.c
json-writer.h
khash.h
kwset.c Merge branch 'rs/copy-array' into maint 2019-07-29 12:38:15 -07:00
kwset.h
levenshtein.c
levenshtein.h
LGPL-2.1
line-log.c Merge branch 'sg/line-log-tree-diff-optim' 2019-09-18 11:50:09 -07:00
line-log.h
line-range.c
line-range.h
linear-assignment.c
linear-assignment.h
list-objects-filter-options.c Merge branch 'jk/partial-clone-sparse-blob' 2019-10-07 11:32:54 +09:00
list-objects-filter-options.h Merge branch 'jk/partial-clone-sparse-blob' 2019-10-07 11:32:54 +09:00
list-objects-filter.c Merge branch 'jk/partial-clone-sparse-blob' 2019-10-07 11:32:54 +09:00
list-objects-filter.h
list-objects.c Merge branch 'jk/list-objects-optim-wo-trees' 2019-10-07 11:32:56 +09:00
list-objects.h
list.h
ll-merge.c am: reload .gitattributes after patching it 2019-09-03 15:16:18 -07:00
ll-merge.h am: reload .gitattributes after patching it 2019-09-03 15:16:18 -07:00
lockfile.c
lockfile.h
log-tree.c Merge branch 'rs/simplify-by-deco-with-deco-refs-exclude' 2019-10-07 11:32:54 +09:00
log-tree.h
ls-refs.c
ls-refs.h
mailinfo.c
mailinfo.h
mailmap.c
mailmap.h
Makefile Merge branch 'js/azure-pipelines-msvc' 2019-10-15 13:48:00 +09:00
match-trees.c
mem-pool.c
mem-pool.h
merge-blobs.c
merge-blobs.h
merge-recursive.c Merge branch 'ew/hashmap' 2019-10-15 13:48:02 +09:00
merge-recursive.h hashmap_entry: remove first member requirement from docs 2019-10-07 10:20:12 +09:00
merge.c
mergesort.c
mergesort.h
midx.c midx: switch to using the_hash_algo 2019-08-19 15:05:00 -07:00
midx.h
name-hash.c hashmap: remove type arg from hashmap_{get,put,remove}_entry 2019-10-07 10:20:12 +09:00
notes-cache.c
notes-cache.h
notes-merge.c
notes-merge.h
notes-utils.c
notes-utils.h
notes.c Merge branch 'mh/notes-duplicate-entries' 2019-09-30 13:19:25 +09:00
notes.h
object-store.h Merge branch 'ds/object-info-for-prefetch-fix' into maint 2019-07-25 14:27:08 -07:00
object.c treewide: remove duplicate #include directives 2019-10-04 08:16:00 +09:00
object.h
oidmap.c hashmap: introduce hashmap_free_entries 2019-10-07 10:20:11 +09:00
oidmap.h hashmap: use *_entry APIs for iteration 2019-10-07 10:20:11 +09:00
oidset.c
oidset.h
pack-bitmap-write.c pack-objects: drop packlist index_pos optimization 2019-09-06 11:03:42 -07:00
pack-bitmap.c Merge branch 'jk/misc-uninitialized-fixes' 2019-09-30 13:19:30 +09:00
pack-bitmap.h pack-bitmap.h: remove magic number 2019-09-28 14:04:20 +09:00
pack-check.c
pack-objects.c pack-objects: drop packlist index_pos optimization 2019-09-06 11:03:42 -07:00
pack-objects.h pack-objects: drop packlist index_pos optimization 2019-09-06 11:03:42 -07:00
pack-revindex.c
pack-revindex.h
pack-write.c pack-write: use hash_to_hex when writing checksums 2019-08-19 15:04:58 -07:00
pack.h
packfile.c Merge branch 'ew/hashmap' 2019-10-15 13:48:02 +09:00
packfile.h Merge branch 'ds/midx-expire-repack' 2019-09-09 12:26:38 -07:00
pager.c
parse-options-cb.c
parse-options.c parse-options: allow --end-of-options as a synonym for "--" 2019-08-06 13:05:39 -07:00
parse-options.h Merge branch 'nd/diff-parseopt' 2019-09-09 12:26:38 -07:00
patch-delta.c
patch-ids.c hashmap: remove type arg from hashmap_{get,put,remove}_entry 2019-10-07 10:20:12 +09:00
patch-ids.h
path.c path: add a function to check for path suffix 2019-08-26 10:36:13 -07:00
path.h path: add a function to check for path suffix 2019-08-26 10:36:13 -07:00
pathspec.c
pathspec.h
pkt-line.c
pkt-line.h
preload-index.c
pretty.c log-tree: call load_ref_decorations() in get_name_decoration() 2019-09-09 11:16:40 -07:00
pretty.h
prio-queue.c
prio-queue.h
progress.c Test the progress display 2019-09-17 09:39:16 -07:00
progress.h
promisor-remote.c promisor-remote: skip move_to_tail when no-op 2019-10-02 14:56:54 +09:00
promisor-remote.h Merge branch 'dl/honor-cflags-in-hdr-check' 2019-10-07 11:33:02 +09:00
prompt.c
prompt.h
protocol.c
protocol.h
quote.c Merge branch 'gs/sq-quote-buf-pretty' 2019-10-15 13:48:02 +09:00
quote.h quote: add sq_append_quote_argv_pretty() 2019-08-09 10:48:02 -07:00
range-diff.c Merge branch 'ew/hashmap' 2019-10-15 13:48:02 +09:00
range-diff.h
reachable.c
reachable.h
read-cache.c Merge branch 'js/azure-pipelines-msvc' 2019-10-15 13:48:00 +09:00
README.md
rebase-interactive.c
rebase-interactive.h
ref-filter.c Merge branch 'ew/hashmap' 2019-10-15 13:48:02 +09:00
ref-filter.h
reflog-walk.c
reflog-walk.h
refs.c hashmap_entry: remove first member requirement from docs 2019-10-07 10:20:12 +09:00
refs.h
refspec.c
refspec.h
RelNotes First batch after Git 2.23 2019-08-22 12:41:04 -07:00
remote-curl.c
remote-testsvn.c
remote.c hashmap: remove type arg from hashmap_{get,put,remove}_entry 2019-10-07 10:20:12 +09:00
remote.h hashmap_entry: remove first member requirement from docs 2019-10-07 10:20:12 +09:00
replace-object.c
replace-object.h
repo-settings.c fetch: add fetch.writeCommitGraph config setting 2019-09-03 12:06:14 -07:00
repository.c
repository.h Merge branch 'jk/disable-commit-graph-during-upload-pack' 2019-10-07 11:32:55 +09:00
rerere.c rerere: replace sha1_to_hex 2019-08-19 15:04:59 -07:00
rerere.h
resolve-undo.c
resolve-undo.h
revision.c Merge branch 'ew/hashmap' 2019-10-15 13:48:02 +09:00
revision.h
run-command.c
run-command.h
send-pack.c send-pack: never fetch when checking exclusions 2019-10-09 10:46:41 +09:00
send-pack.h
sequencer.c Merge branch 'ew/hashmap' 2019-10-15 13:48:02 +09:00
sequencer.h Merge branch 'js/rebase-r-strategy' 2019-09-18 11:50:07 -07:00
serve.c
serve.h
server-info.c
setup.c Merge branch 'js/gitdir-at-unc-root' 2019-09-30 13:19:26 +09:00
sh-i18n--envsubst.c
sha1-array.c
sha1-array.h
sha1-file.c Merge branch 'bc/object-id-part17' 2019-10-11 14:24:46 +09:00
sha1-lookup.c Merge branch 'js/azure-pipelines-msvc' 2019-10-15 13:48:00 +09:00
sha1-lookup.h
sha1-name.c Merge branch 'rs/nth-switch-code-simplification' 2019-10-07 11:33:00 +09:00
sha1dc_git.c
sha1dc_git.h
shallow.c Merge branch 'rs/dedup-includes' 2019-10-11 14:24:48 +09:00
shell.c
shortlog.h
sideband.c
sideband.h
sigchain.c
sigchain.h
split-index.c
split-index.h
stable-qsort.c Move git_sort(), a stable sort, into into libgit.a 2019-10-02 14:44:51 +09:00
strbuf.c Merge branch 'md/list-objects-filter-combo' 2019-09-18 11:50:09 -07:00
strbuf.h Merge branch 'md/list-objects-filter-combo' 2019-09-18 11:50:09 -07:00
streaming.c
streaming.h
string-list.c
string-list.h
sub-process.c hashmap: remove type arg from hashmap_{get,put,remove}_entry 2019-10-07 10:20:12 +09:00
sub-process.h hashmap_entry: remove first member requirement from docs 2019-10-07 10:20:12 +09:00
submodule-config.c hashmap: remove type arg from hashmap_{get,put,remove}_entry 2019-10-07 10:20:12 +09:00
submodule-config.h
submodule.c
submodule.h
symlinks.c
tag.c tag: factor out get_tagged_oid() 2019-09-05 14:10:18 -07:00
tag.h tag: factor out get_tagged_oid() 2019-09-05 14:10:18 -07:00
tar.h
tempfile.c
tempfile.h
thread-utils.c
thread-utils.h
tmp-objdir.c
tmp-objdir.h
trace2.c
trace2.h
trace.c packfile: drop release_pack_memory() 2019-08-13 12:21:33 -07:00
trace.h
trailer.c
trailer.h
transport-helper.c Merge branch 'jt/avoid-ls-refs-with-http' 2019-09-18 11:50:10 -07:00
transport-internal.h transport: teach all vtables to allow fetch first 2019-08-22 14:20:39 -07:00
transport.c transport: push codepath can take arbitrary repository 2019-10-08 13:20:01 +09:00
transport.h
tree-diff.c
tree-walk.c Merge branch 'jk/tree-walk-overflow' 2019-08-22 12:34:10 -07:00
tree-walk.h Merge branch 'jk/tree-walk-overflow' 2019-08-22 12:34:10 -07:00
tree.c tree: simplify parse_tree_indirect() 2019-09-03 15:10:53 -07:00
tree.h
unicode-width.h Merge branch 'bb/unicode-12.1-reiwa' into maint 2019-07-25 14:27:11 -07:00
unimplemented.sh
unix-socket.c
unix-socket.h
unpack-trees.c treewide: remove duplicate #include directives 2019-10-04 08:16:00 +09:00
unpack-trees.h treewide: rename 'struct exclude_list' to 'struct pattern_list' 2019-09-05 14:05:11 -07:00
upload-pack.c Merge branch 'jk/disable-commit-graph-during-upload-pack' 2019-10-07 11:32:55 +09:00
upload-pack.h
url.c
url.h
urlmatch.c
urlmatch.h
usage.c
userdiff.c userdiff: add a builtin pattern for dts files 2019-08-21 15:09:34 -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 Merge branch 'nd/corrupt-worktrees' into maint 2019-07-25 14:27:07 -07:00
worktree.h
wrap-for-bin.sh
wrapper.c Merge branch 'ah/cleanups' 2019-10-09 14:01:00 +09:00
write-or-die.c
ws.c
wt-status.c Merge branch 'bc/object-id-part17' 2019-10-11 14:24:46 +09:00
wt-status.h wt-status: convert struct wt_status to object_id 2019-08-19 15:04:59 -07:00
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>.

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://public-inbox.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