Jonathan Tan [Mon, 16 Aug 2021 21:09:52 +0000 (14:09 -0700)]
grep: use submodule-ODB-as-alternate lazy-addition
In the parent commit, Git was taught to add submodule ODBs as alternates
lazily, but grep does not use this because it computes the path to add
directly, not going through add_submodule_odb(). Add an equivalent to
add_submodule_odb() that takes the exact ODB path and teach grep to use
it.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com> Reviewed-by: Emily Shaffer <emilyshaffer@google.com> Reviewed-by: Matheus Tavares <matheus.bernardino@usp.br> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jonathan Tan [Mon, 16 Aug 2021 21:09:51 +0000 (14:09 -0700)]
submodule: lazily add submodule ODBs as alternates
Teach Git to add submodule ODBs as alternates to the object store of
the_repository only upon the first access of an object not in
the_repository, and not when add_submodule_odb() is called.
This provides a means of gradually migrating from accessing a
submodule's object through alternates to accessing a submodule's object
by explicitly passing its repository object. Any Git command can declare
that it might access submodule objects by calling add_submodule_odb()
(as they do now), but the submodule ODBs themselves will not be added
until needed, so individual commands and/or combinations of arguments
can be migrated one by one.
[The advantage of explicit repository-object passing is code clarity (it
is clear which repository an object read is from), performance (there is
no need to linearly search through all submodule ODBs whenever an object
is accessed from any repository, whether superproject or submodule), and
the possibility of future features like partial clone submodules (which
right now is not possible because if an object is missing, we do not
know which repository to lazy-fetch into).]
This commit also introduces an environment variable that a test may set
to make the actual registration of alternates fatal, in order to
demonstrate that its codepaths do not need this registration.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com> Reviewed-by: Emily Shaffer <emilyshaffer@google.com> Reviewed-by: Matheus Tavares <matheus.bernardino@usp.br> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since c49a177bec (test-lib.sh: set COLUMNS=80 for --verbose
repeatability, 2021-06-29) multiple tests have been failing when using
bash 5 because checkwinsize is enabled by default, therefore COLUMNS is
reset using TIOCGWINSZ even for non-interactive shells.
It's debatable whether or not bash should even be doing that, but for
now we can avoid this undesirable behavior by disabling this option.
Reported-by: Fabian Stelzer <fabian.stelzer@campoint.net> Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
[jc: with SZEDER Gábor's suggestion to do this before setting COLUMNS] Signed-off-by: Junio C Hamano <gitster@pobox.com>
Windows rmdir() equivalent behaves differently from POSIX ones in
that when used on a symbolic link that points at a directory, the
target directory gets removed, which has been corrected.
* tb/mingw-rmdir-symlink-to-directory:
mingw: align symlinks-related rmdir() behavior with Linux
Junio C Hamano [Wed, 4 Aug 2021 20:28:54 +0000 (13:28 -0700)]
Merge branch 'en/ort-perf-batch-14'
Further optimization on "merge -sort" backend.
* en/ort-perf-batch-14:
merge-ort: restart merge with cached renames to reduce process entry cost
merge-ort: avoid recursing into directories when we don't need to
merge-ort: defer recursing into directories when merge base is matched
merge-ort: add a handle_deferred_entries() helper function
merge-ort: add data structures for allowable trivial directory resolves
merge-ort: add some more explanations in collect_merge_info_callback()
merge-ort: resolve paths early when we have sufficient information
Junio C Hamano [Wed, 4 Aug 2021 20:28:52 +0000 (13:28 -0700)]
Merge branch 'ah/plugleaks'
Leak plugging.
* ah/plugleaks:
reset: clear_unpack_trees_porcelain to plug leak
builtin/rebase: fix options.strategy memory lifecycle
builtin/merge: free found_ref when done
builtin/mv: free or UNLEAK multiple pointers at end of cmd_mv
convert: release strbuf to avoid leak
read-cache: call diff_setup_done to avoid leak
ref-filter: also free head for ATOM_HEAD to avoid leak
diffcore-rename: move old_dir/new_dir definition to plug leak
builtin/for-each-repo: remove unnecessary argv copy to plug leak
builtin/submodule--helper: release unused strbuf to avoid leak
environment: move strbuf into block to plug leak
fmt-merge-msg: free newly allocated temporary strings when done
Junio C Hamano [Wed, 4 Aug 2021 20:28:52 +0000 (13:28 -0700)]
Merge branch 'ar/submodule-add'
Rewrite of "git submodule" in C continues.
* ar/submodule-add:
submodule: drop unused sm_name parameter from show_fetch_remotes()
submodule--helper: introduce add-clone subcommand
submodule--helper: refactor module_clone()
submodule: prefix die messages with 'fatal'
t7400: test failure to add submodule in tracked path
Bagas Sanjaya [Wed, 4 Aug 2021 12:24:20 +0000 (19:24 +0700)]
diff: --pickaxe-all typofix
When I was fixing fuzzies as I updating po/id.po for 2.33.0 l10n round,
I noticed a triple-dash typo (--pickaxe-all) at diff.c, which according
to git-diff(1) manpage, the correct option name should be --pickaxe-all.
Fix the typo.
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Acked-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Thomas Bétous [Mon, 2 Aug 2021 21:07:30 +0000 (21:07 +0000)]
mingw: align symlinks-related rmdir() behavior with Linux
When performing a rebase, rmdir() is called on the folder .git/logs. On
Unix rmdir() exits without deleting anything in case .git/logs is a
symbolic link but the equivalent functions on Windows (_rmdir, _wrmdir
and RemoveDirectoryW) do not behave the same and remove the folder if it
is symlinked even if it is not empty.
This creates issues when folders in .git/ are symlinks which is
especially the case when git-repo[1] is used: It replaces `.git/logs/`
with a symlink.
One such issue is that the _target_ of that symlink is removed e.g.
during a `git rebase`, where `delete_reflog("REBASE_HEAD")` will not
only try to remove `.git/logs/REBASE_HEAD` but then recursively try to
remove the parent directories until an error occurs, a technique that
obviously relies on `rmdir()` refusing to remove a symlink.
This was reported in https://github.com/git-for-windows/git/issues/2967.
This commit updates mingw_rmdir() so that its behavior is the same as
Linux rmdir() in case of symbolic links.
To verify that Git does not regress on the reported issue, this patch
adds a regression test for the `git rebase` symptom, even if the same
`rmdir()` behavior is quite likely to cause potential problems in other
Git commands as well.
[1]: git-repo is a python tool built on top of Git which helps manage
many Git repositories. It stores all the .git/ folders in a central
place by taking advantage of symbolic links.
More information: https://gerrit.googlesource.com/git-repo/
Signed-off-by: Thomas Bétous <tomspycell@gmail.com> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
René Scharfe [Fri, 30 Jul 2021 19:06:58 +0000 (21:06 +0200)]
use fspathhash() everywhere
cf2dc1c238 (speed up alt_odb_usable() with many alternates, 2021-07-07)
introduced the function fspathhash() for calculating path hashes while
respecting the configuration option core.ignorecase. Call it instead of
open-coding it; the resulting code is shorter and less repetitive.
Signed-off-by: René Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
t0001: fix broken not-quite getcwd(3) test in bed67874e2
With a54e938e5b (strbuf: support long paths w/o read rights in
strbuf_getcwd() on FreeBSD, 2017-03-26) we had t0001 break on systems
like OpenBSD and AIX whose getcwd(3) has standard (but not like glibc
et al) behavior.
This was partially fixed in bed67874e2 (t0001: skip test with
restrictive permissions if getpwd(3) respects them, 2017-08-07).
The problem with that fix is that while its analysis of the problem is
correct, it doesn't actually call getcwd(3), instead it invokes "pwd
-P". There is no guarantee that "pwd -P" is going to call getcwd(3),
as opposed to e.g. being a shell built-in.
On AIX under both bash and ksh this test breaks because "pwd -P" will
happily display the current working directory, but getcwd(3) called by
the "git init" we're testing here will fail to get it.
I checked whether clobbering the $PWD environment variable would
affect it, and it didn't. Presumably these shells keep track of their
working directory internally.
There's possible follow-up work here in teaching strbuf_getcwd() to
get the working directory with whatever method "pwd" uses on these
platforms. See [1] for a discussion of that, but let's take the easy
way out here and just skip these tests by fixing the
GETCWD_IGNORES_PERMS prerequisite to match the limitations of
strbuf_getcwd().
Andrei Rybak [Thu, 29 Jul 2021 11:02:52 +0000 (13:02 +0200)]
Documentation: render special characters correctly
Three hyphens are rendered verbatim, so "--" has to be used to produce a
dash. There is no double arrow ("<->" is rendered as "<→"), so a left
and right arrow "<-->" have to be combined for that.
So fix asciidoc output for special characters. This is similar to fixes
in commit de82095a95 (doc hash-function-transition: fix asciidoc output,
2021-02-05).
Signed-off-by: Andrei Rybak <rybak.a.v@gmail.com> Acked-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano [Wed, 28 Jul 2021 20:18:04 +0000 (13:18 -0700)]
Merge branch 'tb/reverse-midx'
The code that gives an error message in "git multi-pack-index" when
no subcommand is given tried to print a NULL pointer as a strong,
which has been corrected.
* tb/reverse-midx:
multi-pack-index: fix potential segfault without sub-command
Junio C Hamano [Wed, 28 Jul 2021 20:18:02 +0000 (13:18 -0700)]
Merge branch 'en/rename-limits-doc'
Documentation on "git diff -l<n>" and diff.renameLimit have been
updated, and the defaults for these limits have been raised.
* en/rename-limits-doc:
rename: bump limit defaults yet again
diffcore-rename: treat a rename_limit of 0 as unlimited
doc: clarify documentation for rename/copy limits
diff: correct warning message when renameLimit exceeded
Junio C Hamano [Wed, 28 Jul 2021 20:18:01 +0000 (13:18 -0700)]
Merge branch 'ds/status-with-sparse-index'
"git status" codepath learned to work with sparsely populated index
without hydrating it fully.
* ds/status-with-sparse-index:
t1092: document bad sparse-checkout behavior
fsmonitor: integrate with sparse index
wt-status: expand added sparse directory entries
status: use sparse-index throughout
status: skip sparse-checkout percentage with sparse-index
diff-lib: handle index diffs with sparse dirs
dir.c: accept a directory as part of cone-mode patterns
unpack-trees: unpack sparse directory entries
unpack-trees: rename unpack_nondirectories()
unpack-trees: compare sparse directories correctly
unpack-trees: preserve cache_bottom
t1092: add tests for status/add and sparse files
t1092: expand repository data shape
t1092: replace incorrect 'echo' with 'cat'
sparse-index: include EXTENDED flag when expanding
sparse-index: skip indexes with unmerged entries
Junio C Hamano [Wed, 28 Jul 2021 20:18:01 +0000 (13:18 -0700)]
Merge branch 'js/ci-make-sparse'
The CI gained a new job to run "make sparse" check.
* js/ci-make-sparse:
ci/install-dependencies: handle "sparse" job package installs
ci: run "apt-get update" before "apt-get install"
ci: run `make sparse` as part of the GitHub workflow
Junio C Hamano [Wed, 28 Jul 2021 20:17:58 +0000 (13:17 -0700)]
Merge branch 'jk/log-decorate-optim'
Optimize "git log" for cases where we wasted cycles to load ref
decoration data that may not be needed.
* jk/log-decorate-optim:
load_ref_decorations(): fix decoration with tags
add_ref_decoration(): rename s/type/deco_type/
load_ref_decorations(): avoid parsing non-tag objects
object.h: add lookup_object_by_type() function
object.h: expand docstring for lookup_unknown_object()
log: avoid loading decorations for userformats that don't need it
pretty.h: update and expand docstring for userformat_find_requirements()
Junio C Hamano [Wed, 28 Jul 2021 20:17:58 +0000 (13:17 -0700)]
Merge branch 'sm/worktree-add-lock'
"git worktree add --lock" learned to record why the worktree is
locked with a custom message.
* sm/worktree-add-lock:
worktree: teach `add` to accept --reason <string> with --lock
worktree: mark lock strings with `_()` for translation
t2400: clean up '"add" worktree with lock' test
Junio C Hamano [Wed, 28 Jul 2021 20:17:57 +0000 (13:17 -0700)]
Merge branch 'ew/many-alternate-optim'
Optimization for repositories with many alternate object store.
* ew/many-alternate-optim:
oidtree: a crit-bit tree for odb_loose_cache
oidcpy_with_padding: constify `src' arg
make object_directory.loose_objects_subdir_seen a bitmap
avoid strlen via strbuf_addstr in link_alt_odb_entry
speed up alt_odb_usable() with many alternates
Jeff King [Mon, 26 Jul 2021 17:53:39 +0000 (13:53 -0400)]
ci: run "apt-get update" before "apt-get install"
The "sparse" workflow runs "apt-get install" to pick up a few necessary
packages. But it needs to run "apt-get update" first, or it risks trying
to download an old package version that no longer exists. And in fact
this happens now, with output like:
2021-07-26T17:40:51.2551880Z E: Failed to fetch http://security.ubuntu.com/ubuntu/pool/main/c/curl/libcurl4-openssl-dev_7.68.0-1ubuntu2.5_amd64.deb 404 Not Found [IP: 52.147.219.192 80]
2021-07-26T17:40:51.2554304Z E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?
Our other ci jobs don't suffer from this; they rely on scripts in ci/,
and ci/install-dependencies does the appropriate "apt-get update".
Signed-off-by: Jeff King <peff@peff.net> Acked-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Andrzej Hunt [Sun, 25 Jul 2021 13:08:30 +0000 (15:08 +0200)]
reset: clear_unpack_trees_porcelain to plug leak
setup_unpack_trees_porcelain() populates various fields on
unpack_tree_opts, we need to call clear_unpack_trees_porcelain() to
avoid leaking them. Specifically, we used to leak
unpack_tree_opts.msgs_to_free.
We have to do this in leave_reset_head because there are multiple
scenarios where unpack_tree_opts has already been configured, followed
by a 'goto leave_reset_head'. But we can also 'goto leave_reset_head'
prior to having initialised unpack_tree_opts via memset(..., 0, ...).
Therefore we also move unpack_tree_opts initialisation to the start of
reset_head(), and convert it to use brace initialisation - which
guarantees that we can never clear an uninitialised unpack_tree_opts.
clear_unpack_tree_opts() is always safe to call as long as
unpack_tree_opts is at least zero-initialised, i.e. it does not depend
on a previous call to setup_unpack_trees_porcelain().
LSAN output from t0021:
Direct leak of 192 byte(s) in 1 object(s) allocated from:
#0 0x49ab49 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0xa721e5 in xrealloc wrapper.c:126:8
#2 0x9f7861 in strvec_push_nodup strvec.c:19:2
#3 0x9f7861 in strvec_pushf strvec.c:39:2
#4 0xa43e14 in setup_unpack_trees_porcelain unpack-trees.c:129:3
#5 0x97e011 in reset_head reset.c:53:2
#6 0x61dfa5 in cmd_rebase builtin/rebase.c:1991:9
#7 0x4ce83e in run_builtin git.c:475:11
#8 0x4ccafe in handle_builtin git.c:729:3
#9 0x4cb01c in run_argv git.c:818:4
#10 0x4cb01c in cmd_main git.c:949:19
#11 0x6b3f3d in main common-main.c:52:11
#12 0x7fa8addf3349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Indirect leak of 147 byte(s) in 1 object(s) allocated from:
#0 0x49ab49 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0xa721e5 in xrealloc wrapper.c:126:8
#2 0x9e8d54 in strbuf_grow strbuf.c:98:2
#3 0x9e8d54 in strbuf_vaddf strbuf.c:401:3
#4 0x9f7774 in strvec_pushf strvec.c:36:2
#5 0xa43e14 in setup_unpack_trees_porcelain unpack-trees.c:129:3
#6 0x97e011 in reset_head reset.c:53:2
#7 0x61dfa5 in cmd_rebase builtin/rebase.c:1991:9
#8 0x4ce83e in run_builtin git.c:475:11
#9 0x4ccafe in handle_builtin git.c:729:3
#10 0x4cb01c in run_argv git.c:818:4
#11 0x4cb01c in cmd_main git.c:949:19
#12 0x6b3f3d in main common-main.c:52:11
#13 0x7fa8addf3349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Indirect leak of 134 byte(s) in 1 object(s) allocated from:
#0 0x49ab49 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0xa721e5 in xrealloc wrapper.c:126:8
#2 0x9e8d54 in strbuf_grow strbuf.c:98:2
#3 0x9e8d54 in strbuf_vaddf strbuf.c:401:3
#4 0x9f7774 in strvec_pushf strvec.c:36:2
#5 0xa43fe4 in setup_unpack_trees_porcelain unpack-trees.c:168:3
#6 0x97e011 in reset_head reset.c:53:2
#7 0x61dfa5 in cmd_rebase builtin/rebase.c:1991:9
#8 0x4ce83e in run_builtin git.c:475:11
#9 0x4ccafe in handle_builtin git.c:729:3
#10 0x4cb01c in run_argv git.c:818:4
#11 0x4cb01c in cmd_main git.c:949:19
#12 0x6b3f3d in main common-main.c:52:11
#13 0x7fa8addf3349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Indirect leak of 130 byte(s) in 1 object(s) allocated from:
#0 0x49ab49 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0xa721e5 in xrealloc wrapper.c:126:8
#2 0x9e8d54 in strbuf_grow strbuf.c:98:2
#3 0x9e8d54 in strbuf_vaddf strbuf.c:401:3
#4 0x9f7774 in strvec_pushf strvec.c:36:2
#5 0xa43f20 in setup_unpack_trees_porcelain unpack-trees.c:150:3
#6 0x97e011 in reset_head reset.c:53:2
#7 0x61dfa5 in cmd_rebase builtin/rebase.c:1991:9
#8 0x4ce83e in run_builtin git.c:475:11
#9 0x4ccafe in handle_builtin git.c:729:3
#10 0x4cb01c in run_argv git.c:818:4
#11 0x4cb01c in cmd_main git.c:949:19
#12 0x6b3f3d in main common-main.c:52:11
#13 0x7fa8addf3349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 603 byte(s) leaked in 4 allocation(s).
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
- cmd_rebase populates rebase_options.strategy with newly allocated
strings, hence we need to free those strings at the end of cmd_rebase
to avoid a leak.
- In some cases: get_replay_opts() is called, which prepares replay_opts
using data from rebase_options. We used to simply copy the pointer
from rebase_options.strategy, however that would now result in a
double-free because sequencer_remove_state() is eventually used to
free replay_opts.strategy. To avoid this we xstrdup() strategy when
adding it to replay_opts.
The original leak happens because we always populate
rebase_options.strategy, but we don't always enter the path that calls
get_replay_opts() and later sequencer_remove_state() - in other words
we'd always allocate a new string into rebase_options.strategy but
only sometimes did we free it. We now make sure that rebase_options
and replay_opts both own their own copies of strategy, and each copy
is free'd independently.
This was first seen when running t0021 with LSAN, but t2012 helped catch
the fact that we can't just free(options.strategy) at the end of
cmd_rebase (as that can cause a double-free). LSAN output from t0021:
LSAN output from t0021:
Direct leak of 4 byte(s) in 1 object(s) allocated from:
#0 0x486804 in strdup ../projects/compiler-rt/lib/asan/asan_interceptors.cpp:452:3
#1 0xa71eb8 in xstrdup wrapper.c:29:14
#2 0x61b1cc in cmd_rebase builtin/rebase.c:1779:22
#3 0x4ce83e in run_builtin git.c:475:11
#4 0x4ccafe in handle_builtin git.c:729:3
#5 0x4cb01c in run_argv git.c:818:4
#6 0x4cb01c in cmd_main git.c:949:19
#7 0x6b3fad in main common-main.c:52:11
#8 0x7f267b512349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 4 byte(s) leaked in 1 allocation(s).
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Andrzej Hunt [Sun, 25 Jul 2021 13:08:28 +0000 (15:08 +0200)]
builtin/merge: free found_ref when done
merge_name() calls dwim_ref(), which allocates a new string into
found_ref. Therefore add a free() to avoid leaking found_ref.
LSAN output from t0021:
Direct leak of 16 byte(s) in 1 object(s) allocated from:
#0 0x486804 in strdup ../projects/compiler-rt/lib/asan/asan_interceptors.cpp:452:3
#1 0xa8beb8 in xstrdup wrapper.c:29:14
#2 0x954054 in expand_ref refs.c:671:12
#3 0x953cb6 in repo_dwim_ref refs.c:644:22
#4 0x5d3759 in dwim_ref refs.h:162:9
#5 0x5d3759 in merge_name builtin/merge.c:517:6
#6 0x5d3759 in collect_parents builtin/merge.c:1214:5
#7 0x5cf60d in cmd_merge builtin/merge.c:1458:16
#8 0x4ce83e in run_builtin git.c:475:11
#9 0x4ccafe in handle_builtin git.c:729:3
#10 0x4cb01c in run_argv git.c:818:4
#11 0x4cb01c in cmd_main git.c:949:19
#12 0x6bdbfd in main common-main.c:52:11
#13 0x7f0430502349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 16 byte(s) leaked in 1 allocation(s).
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Andrzej Hunt [Sun, 25 Jul 2021 13:08:27 +0000 (15:08 +0200)]
builtin/mv: free or UNLEAK multiple pointers at end of cmd_mv
These leaks all happen at the end of cmd_mv, hence don't matter in any
way. But we still fix the easy ones and squash the rest to get us closer
to being able to run tests without leaks.
LSAN output from t0050:
Direct leak of 384 byte(s) in 1 object(s) allocated from:
#0 0x49ab49 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0xa8c015 in xrealloc wrapper.c:126:8
#2 0xa0a7e1 in add_entry string-list.c:44:2
#3 0xa0a7e1 in string_list_insert string-list.c:58:14
#4 0x5dac03 in cmd_mv builtin/mv.c:248:4
#5 0x4ce83e in run_builtin git.c:475:11
#6 0x4ccafe in handle_builtin git.c:729:3
#7 0x4cb01c in run_argv git.c:818:4
#8 0x4cb01c in cmd_main git.c:949:19
#9 0x6bd9ad in main common-main.c:52:11
#10 0x7fbfeffc4349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Direct leak of 16 byte(s) in 1 object(s) allocated from:
#0 0x49a82d in malloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:145:3
#1 0xa8bd09 in do_xmalloc wrapper.c:41:8
#2 0x5dbc34 in internal_prefix_pathspec builtin/mv.c:32:2
#3 0x5da575 in cmd_mv builtin/mv.c:158:14
#4 0x4ce83e in run_builtin git.c:475:11
#5 0x4ccafe in handle_builtin git.c:729:3
#6 0x4cb01c in run_argv git.c:818:4
#7 0x4cb01c in cmd_main git.c:949:19
#8 0x6bd9ad in main common-main.c:52:11
#9 0x7fbfeffc4349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Direct leak of 16 byte(s) in 1 object(s) allocated from:
#0 0x49a82d in malloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:145:3
#1 0xa8bd09 in do_xmalloc wrapper.c:41:8
#2 0x5dbc34 in internal_prefix_pathspec builtin/mv.c:32:2
#3 0x5da4e4 in cmd_mv builtin/mv.c:148:11
#4 0x4ce83e in run_builtin git.c:475:11
#5 0x4ccafe in handle_builtin git.c:729:3
#6 0x4cb01c in run_argv git.c:818:4
#7 0x4cb01c in cmd_main git.c:949:19
#8 0x6bd9ad in main common-main.c:52:11
#9 0x7fbfeffc4349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Direct leak of 8 byte(s) in 1 object(s) allocated from:
#0 0x49a9a2 in calloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:154:3
#1 0xa8c119 in xcalloc wrapper.c:140:8
#2 0x5da585 in cmd_mv builtin/mv.c:159:22
#3 0x4ce83e in run_builtin git.c:475:11
#4 0x4ccafe in handle_builtin git.c:729:3
#5 0x4cb01c in run_argv git.c:818:4
#6 0x4cb01c in cmd_main git.c:949:19
#7 0x6bd9ad in main common-main.c:52:11
#8 0x7fbfeffc4349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Direct leak of 4 byte(s) in 1 object(s) allocated from:
#0 0x49a9a2 in calloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:154:3
#1 0xa8c119 in xcalloc wrapper.c:140:8
#2 0x5da4f8 in cmd_mv builtin/mv.c:149:10
#3 0x4ce83e in run_builtin git.c:475:11
#4 0x4ccafe in handle_builtin git.c:729:3
#5 0x4cb01c in run_argv git.c:818:4
#6 0x4cb01c in cmd_main git.c:949:19
#7 0x6bd9ad in main common-main.c:52:11
#8 0x7fbfeffc4349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Indirect leak of 65 byte(s) in 1 object(s) allocated from:
#0 0x49ab49 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0xa8c015 in xrealloc wrapper.c:126:8
#2 0xa00226 in strbuf_grow strbuf.c:98:2
#3 0xa00226 in strbuf_vaddf strbuf.c:394:3
#4 0xa065c7 in xstrvfmt strbuf.c:981:2
#5 0xa065c7 in xstrfmt strbuf.c:991:8
#6 0x9e7ce7 in prefix_path_gently setup.c:115:15
#7 0x9e7fa6 in prefix_path setup.c:128:12
#8 0x5dbdbf in internal_prefix_pathspec builtin/mv.c:55:23
#9 0x5da575 in cmd_mv builtin/mv.c:158:14
#10 0x4ce83e in run_builtin git.c:475:11
#11 0x4ccafe in handle_builtin git.c:729:3
#12 0x4cb01c in run_argv git.c:818:4
#13 0x4cb01c in cmd_main git.c:949:19
#14 0x6bd9ad in main common-main.c:52:11
#15 0x7fbfeffc4349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Indirect leak of 65 byte(s) in 1 object(s) allocated from:
#0 0x49ab49 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0xa8c015 in xrealloc wrapper.c:126:8
#2 0xa00226 in strbuf_grow strbuf.c:98:2
#3 0xa00226 in strbuf_vaddf strbuf.c:394:3
#4 0xa065c7 in xstrvfmt strbuf.c:981:2
#5 0xa065c7 in xstrfmt strbuf.c:991:8
#6 0x9e7ce7 in prefix_path_gently setup.c:115:15
#7 0x9e7fa6 in prefix_path setup.c:128:12
#8 0x5dbdbf in internal_prefix_pathspec builtin/mv.c:55:23
#9 0x5da4e4 in cmd_mv builtin/mv.c:148:11
#10 0x4ce83e in run_builtin git.c:475:11
#11 0x4ccafe in handle_builtin git.c:729:3
#12 0x4cb01c in run_argv git.c:818:4
#13 0x4cb01c in cmd_main git.c:949:19
#14 0x6bd9ad in main common-main.c:52:11
#15 0x7fbfeffc4349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 558 byte(s) leaked in 7 allocation(s).
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Andrzej Hunt [Sun, 25 Jul 2021 13:08:26 +0000 (15:08 +0200)]
convert: release strbuf to avoid leak
apply_multi_file_filter and async_query_available_blobs both query
subprocess output using subprocess_read_status, which writes data into
the identically named filter_status strbuf. We add a strbuf_release to
avoid leaking their contents.
Leak output seen when running t0021 with LSAN:
Direct leak of 24 byte(s) in 1 object(s) allocated from:
#0 0x49ab49 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0xa8c2b5 in xrealloc wrapper.c:126:8
#2 0x9ff99d in strbuf_grow strbuf.c:98:2
#3 0x9ff99d in strbuf_addbuf strbuf.c:304:2
#4 0xa101d6 in subprocess_read_status sub-process.c:45:5
#5 0x77793c in apply_multi_file_filter convert.c:886:8
#6 0x77793c in apply_filter convert.c:1042:10
#7 0x77a0b5 in convert_to_git_filter_fd convert.c:1492:7
#8 0x8b48cd in index_stream_convert_blob object-file.c:2156:2
#9 0x8b48cd in index_fd object-file.c:2248:9
#10 0x597411 in hash_fd builtin/hash-object.c:43:9
#11 0x596be1 in hash_object builtin/hash-object.c:59:2
#12 0x596be1 in cmd_hash_object builtin/hash-object.c:153:3
#13 0x4ce83e in run_builtin git.c:475:11
#14 0x4ccafe in handle_builtin git.c:729:3
#15 0x4cb01c in run_argv git.c:818:4
#16 0x4cb01c in cmd_main git.c:949:19
#17 0x6bdc2d in main common-main.c:52:11
#18 0x7f42acf79349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 24 byte(s) leaked in 1 allocation(s).
Direct leak of 120 byte(s) in 5 object(s) allocated from:
#0 0x49ab49 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0xa8c295 in xrealloc wrapper.c:126:8
#2 0x9ff97d in strbuf_grow strbuf.c:98:2
#3 0x9ff97d in strbuf_addbuf strbuf.c:304:2
#4 0xa101b6 in subprocess_read_status sub-process.c:45:5
#5 0x775c73 in async_query_available_blobs convert.c:960:8
#6 0x80029d in finish_delayed_checkout entry.c:183:9
#7 0xa65d1e in check_updates unpack-trees.c:493:10
#8 0xa5f469 in unpack_trees unpack-trees.c:1747:8
#9 0x525971 in checkout builtin/clone.c:815:6
#10 0x525971 in cmd_clone builtin/clone.c:1409:8
#11 0x4ce83e in run_builtin git.c:475:11
#12 0x4ccafe in handle_builtin git.c:729:3
#13 0x4cb01c in run_argv git.c:818:4
#14 0x4cb01c in cmd_main git.c:949:19
#15 0x6bdc2d in main common-main.c:52:11
#16 0x7fa253fce349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 120 byte(s) leaked in 5 allocation(s).
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Andrzej Hunt [Sun, 25 Jul 2021 13:08:25 +0000 (15:08 +0200)]
read-cache: call diff_setup_done to avoid leak
repo_diff_setup() calls through to diff.c's static prep_parse_options(),
which in turn allocates a new array into diff_opts.parseopts.
diff_setup_done() is responsible for freeing that array, and has the
benefit of verifying diff_opts too - hence we add a call to
diff_setup_done() to avoid leaking parseopts.
Output from the leak as found while running t0090 with LSAN:
Direct leak of 7120 byte(s) in 1 object(s) allocated from:
#0 0x49a82d in malloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:145:3
#1 0xa8bf89 in do_xmalloc wrapper.c:41:8
#2 0x7a7bae in prep_parse_options diff.c:5636:2
#3 0x7a7bae in repo_diff_setup diff.c:4611:2
#4 0x93716c in repo_index_has_changes read-cache.c:2518:3
#5 0x872233 in unclean merge-ort-wrappers.c:12:14
#6 0x872233 in merge_ort_recursive merge-ort-wrappers.c:53:6
#7 0x5d5b11 in try_merge_strategy builtin/merge.c:752:12
#8 0x5d0b6b in cmd_merge builtin/merge.c:1666:9
#9 0x4ce83e in run_builtin git.c:475:11
#10 0x4ccafe in handle_builtin git.c:729:3
#11 0x4cb01c in run_argv git.c:818:4
#12 0x4cb01c in cmd_main git.c:949:19
#13 0x6bdc2d in main common-main.c:52:11
#14 0x7f551eb51349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 7120 byte(s) leaked in 1 allocation(s)
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Andrzej Hunt [Sun, 25 Jul 2021 13:08:24 +0000 (15:08 +0200)]
ref-filter: also free head for ATOM_HEAD to avoid leak
u.head is populated using resolve_refdup(), which returns a newly
allocated string - hence we also need to free() it.
Found while running t0041 with LSAN:
Direct leak of 16 byte(s) in 1 object(s) allocated from:
#0 0x486804 in strdup ../projects/compiler-rt/lib/asan/asan_interceptors.cpp:452:3
#1 0xa8be98 in xstrdup wrapper.c:29:14
#2 0x9481db in head_atom_parser ref-filter.c:549:17
#3 0x9408c7 in parse_ref_filter_atom ref-filter.c:703:30
#4 0x9400e3 in verify_ref_format ref-filter.c:974:8
#5 0x4f9e8b in print_ref_list builtin/branch.c:439:6
#6 0x4f9e8b in cmd_branch builtin/branch.c:757:3
#7 0x4ce83e in run_builtin git.c:475:11
#8 0x4ccafe in handle_builtin git.c:729:3
#9 0x4cb01c in run_argv git.c:818:4
#10 0x4cb01c in cmd_main git.c:949:19
#11 0x6bdc2d in main common-main.c:52:11
#12 0x7f96edf86349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 16 byte(s) leaked in 1 allocation(s).
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Andrzej Hunt [Sun, 25 Jul 2021 13:08:23 +0000 (15:08 +0200)]
diffcore-rename: move old_dir/new_dir definition to plug leak
old_dir/new_dir are free()'d at the end of update_dir_rename_counts,
however if we return early we'll never free those strings. Therefore
we should move all new allocations after the possible early return,
avoiding a leak.
This seems like a fairly recent leak, that started happening since the
early-return was added in: 1ad69eb0dc (diffcore-rename: compute dir_rename_counts in stages, 2021-02-27)
LSAN output from t0022:
Direct leak of 7 byte(s) in 1 object(s) allocated from:
#0 0x486804 in strdup ../projects/compiler-rt/lib/asan/asan_interceptors.cpp:452:3
#1 0xa71e48 in xstrdup wrapper.c:29:14
#2 0x7db9c7 in update_dir_rename_counts diffcore-rename.c:464:12
#3 0x7db6ae in find_renames diffcore-rename.c:1062:3
#4 0x7d76c3 in diffcore_rename_extended diffcore-rename.c:1472:18
#5 0x7b4cfc in diffcore_std diff.c:6705:4
#6 0x855e46 in log_tree_diff_flush log-tree.c:846:2
#7 0x856574 in log_tree_diff log-tree.c:955:3
#8 0x856574 in log_tree_commit log-tree.c:986:10
#9 0x9a9c67 in print_commit_summary sequencer.c:1329:7
#10 0x52e623 in cmd_commit builtin/commit.c:1862:3
#11 0x4ce83e in run_builtin git.c:475:11
#12 0x4ccafe in handle_builtin git.c:729:3
#13 0x4cb01c in run_argv git.c:818:4
#14 0x4cb01c in cmd_main git.c:949:19
#15 0x6b3f3d in main common-main.c:52:11
#16 0x7fe397c7a349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Direct leak of 7 byte(s) in 1 object(s) allocated from:
#0 0x486804 in strdup ../projects/compiler-rt/lib/asan/asan_interceptors.cpp:452:3
#1 0xa71e48 in xstrdup wrapper.c:29:14
#2 0x7db9bc in update_dir_rename_counts diffcore-rename.c:463:12
#3 0x7db6ae in find_renames diffcore-rename.c:1062:3
#4 0x7d76c3 in diffcore_rename_extended diffcore-rename.c:1472:18
#5 0x7b4cfc in diffcore_std diff.c:6705:4
#6 0x855e46 in log_tree_diff_flush log-tree.c:846:2
#7 0x856574 in log_tree_diff log-tree.c:955:3
#8 0x856574 in log_tree_commit log-tree.c:986:10
#9 0x9a9c67 in print_commit_summary sequencer.c:1329:7
#10 0x52e623 in cmd_commit builtin/commit.c:1862:3
#11 0x4ce83e in run_builtin git.c:475:11
#12 0x4ccafe in handle_builtin git.c:729:3
#13 0x4cb01c in run_argv git.c:818:4
#14 0x4cb01c in cmd_main git.c:949:19
#15 0x6b3f3d in main common-main.c:52:11
#16 0x7fe397c7a349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 14 byte(s) leaked in 2 allocation(s).
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Andrzej Hunt [Sun, 25 Jul 2021 13:08:22 +0000 (15:08 +0200)]
builtin/for-each-repo: remove unnecessary argv copy to plug leak
cmd_for_each_repo() copies argv into args (a strvec), which is later
passed into run_command_on_repo(), which in turn copies that strvec onto
the end of child.args. The initial copy is unnecessary (we never modify
args). We therefore choose to just pass argv directly into
run_command_on_repo(), which lets us avoid the copy and fixes the leak.
LSAN output from t0068:
Direct leak of 192 byte(s) in 1 object(s) allocated from:
#0 0x7f63bd4ab8b0 in realloc (/usr/lib64/libasan.so.4+0xdc8b0)
#1 0x98d7e6 in xrealloc wrapper.c:126
#2 0x916914 in strvec_push_nodup strvec.c:19
#3 0x916a6e in strvec_push strvec.c:26
#4 0x4be4eb in cmd_for_each_repo builtin/for-each-repo.c:49
#5 0x410dcd in run_builtin git.c:475
#6 0x410dcd in handle_builtin git.c:729
#7 0x414087 in run_argv git.c:818
#8 0x414087 in cmd_main git.c:949
#9 0x40e9ec in main common-main.c:52
#10 0x7f63bc9fa349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Indirect leak of 22 byte(s) in 2 object(s) allocated from:
#0 0x7f63bd445e30 in __interceptor_strdup (/usr/lib64/libasan.so.4+0x76e30)
#1 0x98d698 in xstrdup wrapper.c:29
#2 0x916a63 in strvec_push strvec.c:26
#3 0x4be4eb in cmd_for_each_repo builtin/for-each-repo.c:49
#4 0x410dcd in run_builtin git.c:475
#5 0x410dcd in handle_builtin git.c:729
#6 0x414087 in run_argv git.c:818
#7 0x414087 in cmd_main git.c:949
#8 0x40e9ec in main common-main.c:52
#9 0x7f63bc9fa349 in __libc_start_main (/lib64/libc.so.6+0x24349)
See also discussion about the original implementation below - this code
appears to have evolved from a callback explaining the double-strvec-copy
pattern, but there's no strong reason to keep that now:
https://lore.kernel.org/git/68bbeca5-314b-08ee-ef36-040e3f3814e9@gmail.com/
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Andrzej Hunt [Sun, 25 Jul 2021 13:08:21 +0000 (15:08 +0200)]
builtin/submodule--helper: release unused strbuf to avoid leak
relative_url() populates sb. In the normal return path, its buffer is
detached using strbuf_detach(). However the early return path does
nothing with sb, which means that sb's memory is leaked - therefore
we add a release to avoid this leak.
The reset is also only necessary for the normal return path, hence we
move it down to after the early-return to avoid unnecessary work.
LSAN output from t0060:
Direct leak of 121 byte(s) in 1 object(s) allocated from:
#0 0x7f31246f28b0 in realloc (/usr/lib64/libasan.so.4+0xdc8b0)
#1 0x98d7d6 in xrealloc wrapper.c:126
#2 0x909a60 in strbuf_grow strbuf.c:98
#3 0x90bf00 in strbuf_vaddf strbuf.c:401
#4 0x90c321 in strbuf_addf strbuf.c:335
#5 0x5cb78d in relative_url builtin/submodule--helper.c:182
#6 0x5cbe46 in resolve_relative_url_test builtin/submodule--helper.c:248
#7 0x410dcd in run_builtin git.c:475
#8 0x410dcd in handle_builtin git.c:729
#9 0x414087 in run_argv git.c:818
#10 0x414087 in cmd_main git.c:949
#11 0x40e9ec in main common-main.c:52
#12 0x7f3123c41349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 121 byte(s) leaked in 1 allocation(s).
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Andrzej Hunt [Sun, 25 Jul 2021 13:08:20 +0000 (15:08 +0200)]
environment: move strbuf into block to plug leak
realpath is only populated if we execute the git_work_tree_initialized
block. However that block also causes us to return early, meaning we
never actually release the strbuf in the case where we populated it.
Therefore we move all strbuf related code into the block to guarantee
that we can't leak it.
LSAN output from t0095:
Direct leak of 129 byte(s) in 1 object(s) allocated from:
#0 0x49a9b9 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0x78f585 in xrealloc wrapper.c:126:8
#2 0x713ff4 in strbuf_grow strbuf.c:98:2
#3 0x713ff4 in strbuf_getcwd strbuf.c:597:3
#4 0x4f0c18 in strbuf_realpath_1 abspath.c:99:7
#5 0x5ae4a4 in set_git_work_tree environment.c:259:3
#6 0x6fdd8a in setup_discovered_git_dir setup.c:931:2
#7 0x6fdd8a in setup_git_directory_gently setup.c:1235:12
#8 0x4cb50d in get_bloom_filter_for_commit t/helper/test-bloom.c:41:2
#9 0x4cb50d in cmd__bloom t/helper/test-bloom.c:95:3
#10 0x4caa1f in cmd_main t/helper/test-tool.c:124:11
#11 0x4caded in main common-main.c:52:11
#12 0x7f0869f02349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 129 byte(s) leaked in 1 allocation(s).
It looks like this leak has existed since realpath was first added to
set_git_work_tree() in: 3d7747e318 (real_path: remove unsafe API, 2020-03-10)
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Andrzej Hunt [Sun, 25 Jul 2021 13:08:19 +0000 (15:08 +0200)]
fmt-merge-msg: free newly allocated temporary strings when done
origin starts off pointing to somewhere within line, which is owned by
the caller. Later we might allocate a new string using xmemdupz() or
xstrfmt(). To avoid leaking these new strings, we introduce a to_free
pointer - which allows us to safely free the newly allocated string when
we're done (we cannot just free origin directly as it might still be
pointing to line).
LSAN output from t0090:
Direct leak of 8 byte(s) in 1 object(s) allocated from:
#0 0x49a82d in malloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:145:3
#1 0xa71f49 in do_xmalloc wrapper.c:41:8
#2 0xa720b0 in do_xmallocz wrapper.c:75:8
#3 0xa720b0 in xmallocz wrapper.c:83:9
#4 0xa720b0 in xmemdupz wrapper.c:99:16
#5 0x8092ba in handle_line fmt-merge-msg.c:187:23
#6 0x8092ba in fmt_merge_msg fmt-merge-msg.c:666:7
#7 0x5ce2e6 in prepare_merge_message builtin/merge.c:1119:2
#8 0x5ce2e6 in collect_parents builtin/merge.c:1215:3
#9 0x5c9c1e in cmd_merge builtin/merge.c:1454:16
#10 0x4ce83e in run_builtin git.c:475:11
#11 0x4ccafe in handle_builtin git.c:729:3
#12 0x4cb01c in run_argv git.c:818:4
#13 0x4cb01c in cmd_main git.c:949:19
#14 0x6b3fad in main common-main.c:52:11
#15 0x7fb929620349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 8 byte(s) leaked in 1 allocation(s).
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Philippe Blain [Fri, 23 Jul 2021 12:14:30 +0000 (12:14 +0000)]
merge: apply autostash if merge strategy fails
Since 'git merge' learned '--autostash' in a03b55530a (merge: teach
--autostash option, 2020-04-07), 'cmd_merge', once it is determined that
we have to create a merge commit, calls 'create_autostash' if
'--autostash' is given.
As explained in a03b55530a, and made more abvious by the tests added in
that commit, the autostash is then applied if the merge succeeds, either
directly or by committing (after conflict resolution or if '--no-commit'
was given), or if the merge is aborted with 'git merge --abort'. In some
other cases, like the user calling 'git reset --merge' or 'git merge
--quit', the autostash is not applied, but saved in the stash list.
However, there exists a scenario that creates an autostash but does not
apply nor save it to the stash list: if the chosen merge strategy
completely fails to handle the merge, i.e. 'try_merge_strategy' returns
2.
Apply the autostash in that case also. An easy way to test that is to
try to merge more than two commits but explicitely ask for the 'recursive'
merge strategy.
Signed-off-by: Philippe Blain <levraiphilippeblain@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Philippe Blain [Fri, 23 Jul 2021 12:14:29 +0000 (12:14 +0000)]
merge: apply autostash if fast-forward fails
Since 'git merge' learned '--autostash' in a03b55530a (merge: teach
--autostash option, 2020-04-07), 'cmd_merge', in the fast-forward case,
calls 'create_autostash' before calling 'checkout_fast_forward' if
'--autostash' is given.
However, if 'checkout_fast_forward' fails, the autostash is not applied
to the working tree, nor saved in the stash list, since the code simply
calls 'goto done'.
Be more helpful to the user by applying the autostash in that case.
An easy way to test a failing fast-forward is when we are merging a
branch that has a tracked file that conflicts with an untracked file in
the working tree.
Signed-off-by: Philippe Blain <levraiphilippeblain@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Philippe Blain [Fri, 23 Jul 2021 12:14:28 +0000 (12:14 +0000)]
Documentation: define 'MERGE_AUTOSTASH'
The documentation for 'git merge --abort' and 'git merge --quit' both
mention the special ref 'MERGE_AUTOSTASH', but this ref is not formally
defined anywhere. Mention it in the description of the '--autostash'
option for 'git merge'.
Signed-off-by: Philippe Blain <levraiphilippeblain@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Philippe Blain [Fri, 23 Jul 2021 12:14:27 +0000 (12:14 +0000)]
merge: add missing word "strategy" to a message
The variable 'best_strategy' holds the name of the merge strategy that
resulted in fewer conflicts, if several strategies were tried. When
that's the case but the best strategy was not the first one tried, we
inform the user which strategy was the "best" one before recreating the
merge and leaving the conflicted files in the tree.
This informational message is missing the word "strategy", so it shows
something like:
Using the recursive to prepare resolving by hand.
Fix that.
Signed-off-by: Philippe Blain <levraiphilippeblain@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jonathan Tan [Fri, 23 Jul 2021 18:52:23 +0000 (11:52 -0700)]
cache-tree: prefetch in partial clone read-tree
"git read-tree" checks the existence of the blobs referenced by the
given tree, but does not bulk prefetch them. Add a bulk prefetch.
The lack of prefetch here was noticed at $DAYJOB during a merge
involving some specific commits, but I couldn't find a minimal merge
that didn't also trigger the prefetch in check_updates() in
unpack-trees.c (and in all these cases, the lack of prefetch in
cache-tree.c didn't matter because all the relevant blobs would have
already been prefetched by then). This is why I used read-tree here to
exercise this code path.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King [Fri, 23 Jul 2021 09:29:34 +0000 (05:29 -0400)]
pack-bitmap: check pack validity when opening bitmap
When pack-objects adds an entry to its list of objects to pack, it may
mark the packfile and offset that contains the file, which we can later
use to output the object verbatim. If the packfile is deleted while we
are running (e.g., by another process running "git repack"), we may die
in use_pack() if the pack file cannot be opened.
We worked around this in 4c08018204 (pack-objects: protect against
disappearing packs, 2011-10-14) by making sure we can open the pack
before recording it as a source. This detects a pack which has already
disappeared while generating the packing list, and because we keep the
pack's file descriptor (or an mmap window) open, it means we can access
it later (unless you exceed core.packedgitlimit).
The bitmap code that was added later does not do this; it adds entries
to the packlist without checking that the packfile is still valid, and
is vulnerable to this race. It needs the same treatment as 4c08018204.
However, rather than add it in just that one spot, it makes more sense
to simply open and check the packfile when we open the bitmap.
Technically you can use the .bitmap without even looking in the .pack
file (e.g., if you are just printing a list of objects without accessing
them), but it's much simpler to do it early. That covers all later
direct uses of the pack (due to the cached descriptor) without having to
check each one directly. For example, in pack-objects we need to protect
the packlist entries, but we also access the pack directly as part of
the reuse_partial_pack_from_bitmap() feature. This patch covers both
cases.
There's no test here, because the problem is inherently racy. I
reproduced and verified the fix with this script:
git init --bare parent.git &&
git --git-dir=parent.git config transfer.unpacklimit 1 &&
git clone parent.git push.git &&
(for i in `seq 1 1000`; do push $i || break; done) &
pusher=$!
(for i in `seq 1 1000`; do fetch $i || break; done) &
fetcher=$!
wait $fetcher
kill $pusher
That simulates a race between a client cloning and a push triggering a
repack on the server. Without this patch, it generally fails within a
couple hundred iterations with:
remote: fatal: packfile ./objects/pack/.tmp-1377349-pack-498afdec371232bdb99d1757872f5569331da61e.pack cannot be accessed
error: git upload-pack: git-pack-objects died with error.
fatal: git upload-pack: aborting due to possible repository corruption on the remote side.
remote: aborting due to possible repository corruption on the remote side.
fatal: early EOF
fatal: fetch-pack: invalid index-pack output
With this patch, it reliably runs through all thousand attempts.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change the bundle tests to fully compare the expected "git ls-remote"
or "git bundle list-heads" output, instead of merely grepping it.
This avoids subtle regressions in the tests. In f62e0a39b6 (t5704 (bundle): add tests for bundle --stdin, 2010-04-19)
the "bundle --stdin <rev-list options>" test was added to make sure we
didn't include the tag.
But since the --stdin mode didn't work until 5bb0fd2cab (bundle:
arguments can be read from stdin, 2021-01-11) our grepping of
"master" (later "main") missed the important part of the test.
Namely that we should not include the "refs/tags/tag" tag in that
case. Since the test only grepped for "main" in the output we'd miss a
regression in that code.
So let's use test_cmp instead, and also in the other nearby tests
where it's easy.
This does make things a bit more verbose in the case of the test
that's checking the bundle header, since it's different under SHA1 and
SHA256. I think this makes test easier to follow.
I've got some WIP changes to extend the "git bundle" command to dump
parts of the header out, which are easier to understand if we test the
output explicitly like this.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano [Thu, 22 Jul 2021 20:05:55 +0000 (13:05 -0700)]
Merge branch 'js/ci-windows-update'
GitHub Actions / CI update.
* js/ci-windows-update:
ci: accelerate the checkout
ci (vs-build): build with NO_GETTEXT
artifacts-tar: respect NO_GETTEXT
ci (windows): transfer also the Git-tracked files to the test jobs
ci: upgrade to using actions/{up,down}load-artifacts v2
ci (vs-build): use `cmd` to copy the DLLs, not `powershell`
ci: use the new GitHub Action to download git-sdk-64-minimal
Junio C Hamano [Thu, 22 Jul 2021 20:05:54 +0000 (13:05 -0700)]
Merge branch 'ab/send-email-optim'
"git send-email" optimization.
* ab/send-email-optim:
perl: nano-optimize by replacing Cwd::cwd() with Cwd::getcwd()
send-email: move trivial config handling to Perl
perl: lazily load some common Git.pm setup code
send-email: lazily load modules for a big speedup
send-email: get rid of indirect object syntax
send-email: use function syntax instead of barewords
send-email: lazily shell out to "git var"
send-email: lazily load config for a big speedup
send-email: copy "config_regxp" into git-send-email.perl
send-email: refactor sendemail.smtpencryption config parsing
send-email: remove non-working support for "sendemail.smtpssl"
send-email tests: test for boolean variables without a value
send-email tests: support GIT_TEST_PERL_FATAL_WARNINGS=true
SubmittingPatches: replace discussion of Travis with GitHub Actions
Replace the discussion of Travis CI added in 0e5d028a7a0 (Documentation: add setup instructions for Travis CI,
2016-05-02) with something that covers the GitHub Actions added in 889cacb6897 (ci: configure GitHub Actions for CI/PR, 2020-04-11).
The setup is trivial compared to using Travis, and it even works on
Windows (that "hopefully soon" comment was probably out-of-date on
Travis as well).
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
SubmittingPatches: move discussion of Signed-off-by above "send"
Move the section discussing the addition of a SOB trailer above the
section that discusses generating the patch itself. This makes sense
as we don't want someone to go through the process of "git
format-patch", only to realize late that they should have used "git
commit -s" or equivalent.
This is a move-only change, no lines here are being altered, only
moved around.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Felipe Contreras [Wed, 21 Jul 2021 22:15:45 +0000 (17:15 -0500)]
doc: pull: fix rebase=false documentation
"git pull --rebase=false" means we merge their history into ours, but
it has been described the other way around.
Cc: Stephen Haberman <stephen@exigencecorp.com> Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
[jc: updated the log message] Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau [Tue, 20 Jul 2021 20:16:22 +0000 (16:16 -0400)]
pack-bitmap: clarify comment in filter_bitmap_exclude_type()
The code that eventually became filter_bitmap_exclude_type() was
originally introduced in 4f3bd5606a (pack-bitmap: implement BLOB_NONE
filtering, 2020-02-14) to accelerate BLOB_NONE filters with bitmaps.
In 856e12c18a (pack-bitmap.c: make object filtering functions generic,
2020-05-04), it became filter_bitmap_exclude_type(). But not all of the
comments were updated to be agnostic to the provided type.
Remove the remaining comments which should have been updated in 856e12c18a to reflect the type-agnostic nature of the function.
Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
When running unpack_trees() with a sparse index, we attempt to operate
on the index without expanding the sparse directory entries. Thus, we
operate by manipulating entire directories and passing them to the
unpack function. In the case of the 'git checkout' command, this is the
twoway_merge() function.
There are several cases in twoway_merge() that handle different
situations. One new one to add is the case of a directory/file conflict
where the directory is sparse. Before the sparse index, such a conflict
would appear as a list of file additions and deletions. Now,
twoway_merge() initializes 'current', 'oldtree', and 'newtree' from
src[0], src[1], and src[2], then sets 'oldtree' to NULL because it is
equal to the df_conflict_entry. The way to determine that we have a
directory/file conflict is to test that 'current' and 'newtree' disagree
on being sparse directory entries.
When we are in this case, we want to resolve the situation by calling
merged_entry(). This allows replacing the 'current' entry with the
'newtree' entry. This is important for cases where we want to run 'git
checkout' across the conflict and have the new HEAD represent the new
file type at that path. The first NEEDSWORK comment dropped in t1092
demonstrates this necessary behavior.
However, we still are in a confusing state when 'current' corresponds to
a staged change within a sparse directory that is not present at HEAD.
This should be atypical, because it requires adding a change outside of
the sparse-checkout cone, but it is possible. Since we are unable to
determine that this is a staged change within twoway_merge(), we cannot
add a case to reject the merge at this point. I believe this is due to
the use of df_conflict_entry in the place of 'oldtree' instead of using
the valud at HEAD, which would provide some perspective to this
decision. Any change that would allow this differentiation for staged
entries would need to involve information further up in unpack_trees().
That work should be done, sometime, because we are further confusing the
behavior of a directory/file conflict when staging a change in the
directory. The two cases 'checkout behaves oddly with df-conflict-?' in
t1092 demonstrate that even without a sparse-checkout, Git is not
consistent in its behavior. Neither of the two options seems correct,
either. This change makes the sparse-index behave differently than the
typcial sparse-checkout case, but it does match the full checkout
behavior in the df-conflict-2 case.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add new branches to the test repo that demonstrate directory/file
conflicts in different ways. Since the directory 'folder1/' has
adjacent files 'folder1-', 'folder1.txt', and 'folder10' it causes
searches for 'folder1/' to land in a different place in the index than a
search for 'folder1'. This causes a change in behavior when working with
the df-conflict-1 and df-conflict-2 branches, whose only difference is
that the first uses 'folder1' as the conflict and the other uses
'folder2' which does not have these adjacent files.
We can extend two tests that compare the behavior across different 'git
checkout' commands, and we see already that the behavior will be
different in some cases and not in others. The difference between the
two test loops is that one uses 'git reset --hard' between iterations.
Further, we isolate the behavior of creating a staged change within a
directory and then checking out a branch where that directory is
replaced with a file. A full checkout behaves differently across these
two cases, while a sparse-checkout cone behaves consistently. In both
cases, the behavior is wrong. In one case, the staged change is dropped
entirely. The other case the staged change is kept, replacing the file
at that location, but none of the other files in the directory are kept.
Likely, the correct behavior in this case is to reject the checkout and
report the conflict, leaving HEAD in its previous location. None of the
cases behave this way currently. Use comments to demonstrate that the
tested behavior is only a documentation of the current, incorrect
behavior to ensure we do not _accidentally_ change it. Instead, we would
prefer to change it on purpose with a future change.
At this point, the sparse-index does not handle these 'git checkout'
commands correctly. Or rather, it _does_ reject the 'git checkout' when
we have the staged change, but for the wrong reason. It also rejects the
'git checkout' commands when there is no staged change and we want to
replace a directory with a file. A fix for that unstaged case will
follow in the next change, but that will make the sparse-index agree
with the full checkout case in these documented incorrect behaviors.
Helped-by: Elijah Newren <newren@gmail.com> Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Philippe Blain [Fri, 16 Jul 2021 03:02:57 +0000 (03:02 +0000)]
doc: clarify description of 'submodule.recurse'
The doc for 'submodule.recurse' starts with "Specifies if commands
recurse into submodles by default". This is not exactly true of all
commands that have a '--recurse-submodules' option. For example, 'git
pull --recurse-submodules' does not run 'git pull' in each submodule,
but rather runs 'git submodule update --recursive' so that the submodule
working trees after the pull matches the commits recorded in the
superproject.
Clarify that by just saying that it enables '--recurse-submodules'.
Note that the way this setting interacts with 'fetch.recurseSubmodules'
and 'push.recurseSubmodules', which can have other values than true or
false, is already documented since 4da9e99e6e (doc: be more precise on
(fetch|push).recurseSubmodules, 2020-04-06).
Signed-off-by: Philippe Blain <levraiphilippeblain@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King [Wed, 14 Jul 2021 21:38:27 +0000 (17:38 -0400)]
doc/git-config: simplify "override" advice for FILES section
At the end of the FILES section, we indicate that you can override the
regular lookup rules with --global, etc. But:
- we're missing the --local option
- we point to GIT_CONFIG instead of --file, but the latter has much
better documentation
- we're vague about how the overrides work; the actual option
descriptions are much better here
So let's just mention the names and point people back to the OPTIONS
section. We could perhaps even delete this paragraph entirely, but the
presence of the names may give people reading FILES a clue about where
to look for more information.
Signed-off-by: Jeff King <peff@peff.net> Reviewed-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The scope and utility of the GIT_CONFIG variable was drastically reduced
by dc87183189 (Only use GIT_CONFIG in "git config", not other programs,
2008-06-30). But the documentation in git-config(1) predates that, which
makes it rather misleading.
These days it is really just another way to say "--file". So let's say
that, and explicitly make it clear that it does not impact other Git
commands (like GIT_CONFIG_SYSTEM, etc, would).
I also bumped it to the bottom of the list of variables, and warned
people off of using it. We don't have any plans for deprecation at this
point, but there's little point in encouraging people to use it by
putting it at the top of the list.
Signed-off-by: Jeff King <peff@peff.net> Reviewed-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King [Wed, 14 Jul 2021 21:37:29 +0000 (17:37 -0400)]
doc/git-config: explain --file instead of referring to GIT_CONFIG
The explanation for the --file option only refers to GIT_CONFIG. This
redirection to an environment variable is confusing, but doubly so
because the description of GIT_CONFIG is out of date.
Let's describe --file from scratch, detailing both the reading and
writing behavior as we do for other similar options like --system, etc.
Signed-off-by: Jeff King <peff@peff.net> Reviewed-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
merge-ort: restart merge with cached renames to reduce process entry cost
The merge algorithm mostly consists of the following three functions:
collect_merge_info()
detect_and_process_renames()
process_entries()
Prior to the trivial directory resolution optimization of the last half
dozen commits, process_entries() was consistently the slowest, followed
by collect_merge_info(), then detect_and_process_renames(). When the
trivial directory resolution applies, it often dramatically decreases
the amount of time spent in the two slower functions.
Looking at the performance results in the previous commit, the trivial
directory resolution optimization helps amazingly well when there are no
relevant renames. It also helps really well when reapplying a long
series of linear commits (such as in a rebase or cherry-pick), since the
relevant renames may well be cached from the first reapplied commit.
But when there are any relevant renames that are not cached (represented
by the just-one-mega testcase), then the optimization does not help at
all.
Often, I noticed that when the optimization does not apply, it is
because there are a handful of relevant sources -- maybe even only one.
It felt frustrating to need to recurse into potentially hundreds or even
thousands of directories just for a single rename, but it was needed for
correctness.
However, staring at this list of functions and noticing that
process_entries() is the most expensive and knowing I could avoid it if
I had cached renames suggested a simple idea: change
collect_merge_info()
detect_and_process_renames()
process_entries()
into
collect_merge_info()
detect_and_process_renames()
<cache all the renames, and restart>
collect_merge_info()
detect_and_process_renames()
process_entries()
This may seem odd and look like more work. However, note that although
we run collect_merge_info() twice, the second time we get to employ
trivial directory resolves, which makes it much faster, so the increased
time in collect_merge_info() is small. While we run
detect_and_process_renames() again, all renames are cached so it's
nearly a no-op (we don't call into diffcore_rename_extended() but we do
have a little bit of data structure checking and fixing up). And the
big payoff comes from the fact that process_entries(), will be much
faster due to having far fewer entries to process.
This restarting only makes sense if we can save recursing into enough
directories to make it worth our while. Introduce a simple heuristic to
guide this. Note that this heuristic uses a "wanted_factor" that I have
virtually no actual real world data for, just some back-of-the-envelope
quasi-scientific calculations that I included in some comments and then
plucked a simple round number out of thin air. It could be that
tweaking this number to make it either higher or lower improves the
optimization. (There's slightly more here; when I first introduced this
optimization, I used a factor of 10, because I was completely confident
it was big enough to not cause slowdowns in special cases. I was
certain it was higher than needed. Several months later, I added the
rough calculations which make me think the optimal number is close to 2;
but instead of pushing to the limit, I just bumped it to 3 to reduce the
risk that there are special cases where this optimization can result in
slowing down the code a little. If the ratio of path counts is below 3,
we probably will only see minor performance improvements at best
anyway.)
Also, note that while the diffstat looks kind of long (nearly 100
lines), more than half of it is in two comments explaining how things
work.
For the testcases mentioned in commit 557ac0350d ("merge-ort: begin
performance work; instrument with trace2_region_* calls", 2020-10-28),
this change improves the performance as follows:
Before After
no-renames: 205.1 ms ± 3.8 ms 204.2 ms ± 3.0 ms
mega-renames: 1.564 s ± 0.010 s 1.076 s ± 0.015 s
just-one-mega: 479.5 ms ± 3.9 ms 364.1 ms ± 7.0 ms
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
merge-ort: avoid recursing into directories when we don't need to
This combines the work of the last several patches, and implements the
conditions when we don't need to recurse into directories. It's perhaps
easiest to see the logic by separating the fact that a directory might
have both rename sources and rename destinations:
* rename sources: only files present in the merge base can serve as
rename sources, and only when one side deletes that file. When the
tree on one side matches the merge base, that means every file
within the subtree matches the merge base. This means that the
skip-irrelevant-rename-detection optimization from before kicks in
and we don't need any of these files as rename sources.
* rename destinations: the tree that does not match the merge base
might have newly added and hence unmatched destination files.
This is what usually prevents us from doing trivial directory
resolutions in the merge machinery. However, the fact that we have
deferred recursing into this directory until the end means we know
whether there are any unmatched relevant potential rename sources
elsewhere in this merge. If there are no unmatched such relevant
sources anywhere, then there is no need to look for unmatched
potential rename destinations to match them with.
This informs our algorithm:
* Search through relevant_sources; if we have entries, they better all
be reflected in cached_pairs or cached_irrelevant, otherwise they
represent an unmatched potential rename source (causing the
optimization to be disallowed).
* For any relevant_source represented in cached_pairs, we do need to
to make sure to get the destination for each source, meaning we need
to recurse into any ancestor directories of those destinations.
* Once we've recursed into all the rename destinations for any
relevant_sources in cached_pairs, we can then do the trivial
directory resolution for the remaining directories.
For the testcases mentioned in commit 557ac0350d ("merge-ort: begin
performance work; instrument with trace2_region_* calls", 2020-10-28),
this change improves the performance as follows:
Before After
no-renames: 5.235 s ± 0.042 s 205.1 ms ± 3.8 ms
mega-renames: 9.419 s ± 0.107 s 1.564 s ± 0.010 s
just-one-mega: 480.1 ms ± 3.9 ms 479.5 ms ± 3.9 ms
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
merge-ort: defer recursing into directories when merge base is matched
When one side of history matches the merge base (including when the
merge base has no entry for the given directory), have
collect_merge_info_callback() defer recursing into the directory. To
ensure those entries are eventually handled, add a call to
handled_deferred_entries() in collect_merge_info() after
traverse_trees() returns.
Note that the condition in collect_merge_info_callback() may look more
complicated than necessary at first glance;
renames->trivial_merges_okay[side] is always true until
handle_deferred_entries() is called, and possible_trivial_merges[side]
is always empty right now (and in the future won't be filled until
handle_deferred_entries() is called). However, when
handle_deferred_entries() calls traverse_trees() for the relevant
deferred directories, those traverse_trees() calls will once again end
up in collect_merge_info_callback() for all the entries under those
subdirectories. The extra conditions are there for such deferred cases
and will be used more as we do more with those variables.
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
merge-ort: add a handle_deferred_entries() helper function
In order to allow trivial directory resolution, we first need to be able
to gather more information to determine if the optimization is safe. To
enable that, we need a way of deferring the recursion into the directory
until a later time. Naturally, deferring the entry into a subtree means
that we need some function that will later recurse into the subdirectory
exactly the same way that collect_merge_info_callback() would have done.
Add a helper function that does this. For now this function is not used
but a subsequent commit will change that. Future commits will also make
the function sometimes resolve directories instead of traversing inside.
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
merge-ort: add data structures for allowable trivial directory resolves
As noted a few commits ago, we can resolve individual files early if all
three sides of the merge have a file at the path and two of the three
sides match. We would really like to do the same thing with
directories, because being able to do a trivial directory resolve means
we don't have to recurse into the directory, potentially saving us a
huge amount of time in both collect_merge_info() and process_entries().
Unfortunately, resolving directories early would mean missing any
renames whose source or destination is underneath that directory.
If we somehow knew there weren't any renames under the directory in
question, then we could resolve it early. Sadly, it is impossible to
determine whether there are renames under the directory in question
without recursing into it, and this has traditionally kept us from ever
implementing such an optimization.
In commit f89b4f2bee ("merge-ort: skip rename detection entirely if
possible", 2021-03-11), we added an additional reason that rename
detection could be skipped entirely -- namely, if no *relevant* sources
were present. Without completing collect_merge_info_callback(), we do
not yet know if there are no relevant sources. However, we do know that
if the current directory on one side matches the merge base, then every
source file within that directory will not be RELEVANT_CONTENT, and a
few simple checks can often let us rule out RELEVANT_LOCATION as well.
This suggests we can just defer recursing into such directories until
the end of collect_merge_info.
Since the deferred directories are known to not add any relevant sources
due to the above properties, then if there are no relevant sources after
we've traversed all paths other than the deferred ones, then we know
there are not any relevant sources. Under those conditions, rename
detection is unnecessary, and that means we can resolve the deferred
directories without recursing into them.
Note that the logic for skipping rename detection was also modified
further in commit 76e253793c ("merge-ort, diffcore-rename: employ cached
renames when possible", 2021-01-30); in particular rename detection can
be skipped if we already have cached renames for each relevant source.
We can take advantage of this information as well with our deferral of
recursing into directories where one side matches the merge base.
Add some data structures that we will use to do these deferrals, with
some lengthy comments explaining their purpose.
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
merge-ort: add some more explanations in collect_merge_info_callback()
The previous patch possibly raises some questions about whether
additional cases in collect_merge_info_callback() can be handled early.
Add some explanations in the form of comments to help explain these
better. While we're at it, add a few comments to denote what a few
boolean '0' or '1' values stand for.
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
merge-ort: resolve paths early when we have sufficient information
When there are no directories involved at a given path, and all three
sides have a file at that path, and two of the three sides of history
match, we can immediately resolve the merge of that path in
collect_merge_info() and do not need to wait until process_entries().
This is actually a very minor improvement: half the time when I run it,
I see an improvement; the other half a slowdown. It seems to be in the
range of noise. However, this idea serves as the beginning of some
bigger optimizations coming in the following patches.
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
projects / thirdparty / git.git / log
