Jerry Zhang [Thu, 29 Apr 2021 02:35:03 +0000 (19:35 -0700)]
apply: adjust messages to account for --3way changes
"git apply" specifically calls out when it is falling back to 3way
merge application. Since the order changed to preferring 3way and
falling back to direct application, continue that behavior by
printing whenever 3way fails and git has to fall back.
Signed-off-by: Jerry Zhang <jerry@skydio.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King [Wed, 28 Apr 2021 15:42:43 +0000 (11:42 -0400)]
prune: save reachable-from-recent objects with bitmaps
We pass our prune expiration to mark_reachable_objects(), which will
traverse not only the reachable objects, but consider any recent ones as
tips for reachability; see d3038d22f9 (prune: keep objects reachable
from recent objects, 2014-10-15) for details.
However, this interacts badly with the bitmap code path added in fde67d6896 (prune: use bitmaps for reachability traversal, 2019-02-13).
If we hit the bitmap-optimized path, we return immediately to avoid the
regular traversal, accidentally skipping the "also traverse recent"
code.
Instead, we should do an if-else for the bitmap versus regular
traversal, and then follow up with the "recent" traversal in either
case. This reuses the "rev_info" for a bitmap and then a regular
traversal, but that should work OK (the bitmap code clears the pending
array in the usual way, just like a regular traversal would).
Note that I dropped the comment above the regular traversal here. It
has little explanatory value, and makes the if-else logic much harder to
read.
Here are a few variants that I rejected:
- it seems like both the reachability and recent traversals could be
done in a single traversal. This was rejected by d3038d22f9 (prune:
keep objects reachable from recent objects, 2014-10-15), though the
balance may be different when using bitmaps. However, there's a
subtle correctness issue, too: we use revs->ignore_missing_links for
the recent traversal, but not the reachability one.
- we could try using bitmaps for the recent traversal, too, which
could possibly improve performance. But it would require some fixes
in the bitmap code, which uses ignore_missing_links for its own
purposes. Plus it would probably not help all that much in practice.
We use the reachable tips to generate bitmaps, so those objects are
likely not covered by bitmaps (unless they just became unreachable).
And in general, we expect the set of unreachable objects to be much
smaller anyway, so there's less to gain.
The test in t5304 detects the bug and confirms the fix.
I also beefed up the tests in t6501, which covers the mtime-checking
code more thoroughly, to handle the bitmap case (in addition to just
"loose" and "packed" cases). Interestingly, this test doesn't actually
detect the bug, because it is running "git gc", and not "prune"
directly. And "gc" will call "repack" first, which does not suffer the
same bug. So the old-but-reachable-from-recent objects get scooped up
into the new pack along with the actually-recent objects, which gives
both a recent mtime. But it seemed prudent to get more coverage of the
bitmap case for related code.
Reported-by: David Emett <dave@sp4m.net> Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King [Wed, 28 Apr 2021 15:42:30 +0000 (11:42 -0400)]
pack-bitmap: clean up include_check after use
When a bitmap walk has to traverse (to fill in non-bitmapped objects),
we use rev_info's include_check mechanism to let us stop the traversal
early. But after setting the function and its data parameter, we never
clean it up. This means that if the rev_info is used for a subsequent
traversal without bitmaps, it will unexpectedly call into our
include_check function (worse, it will do so pointing to a now-defunct
stack variable in include_check_data, likely resulting in a segfault).
There's no code which does this now, but it's an accident waiting to
happen. Let's clean up after ourselves in the bitmap code.
Reported-by: David Emett <dave@sp4m.net> Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Tue, 27 Apr 2021 21:17:48 +0000 (15:17 -0600)]
subtree: be stricter about validating flags
Don't silently ignore a flag that's invalid for a given subcommand. The
user expected it to do something; we should tell the user that they are
mistaken, instead of surprising the user.
It could be argued that this change might break existing users. I'd
argue that those existing users are already broken, and they just don't
know it. Let them know that they're broken.
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Tue, 27 Apr 2021 21:17:47 +0000 (15:17 -0600)]
subtree: push: allow specifying a local rev other than HEAD
'git subtree split' lets you specify a rev other than HEAD. 'git push'
lets you specify a mapping between a local thing and a remot ref. So
smash those together, and have 'git subtree push' let you specify which
local thing to run split on and push the result of that split to the
remote ref.
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Tue, 27 Apr 2021 21:17:46 +0000 (15:17 -0600)]
subtree: allow 'split' flags to be passed to 'push'
'push' does a 'split' internally, but it doesn't pass flags through to the
'split'. This is silly, if you need to pass flags to 'split', then it
means that you can't use 'push'!
So, have 'push' accept 'split' flags, and pass them through to 'split'.
Add tests for this by copying split's tests with minimal modification.
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Tue, 27 Apr 2021 21:17:45 +0000 (15:17 -0600)]
subtree: allow --squash to be used with --rejoin
Besides being a genuinely useful thing to do, this also just makes sense
and harmonizes which flags may be used when. `git subtree split
--rejoin` amounts to "automatically go ahead and do a `git subtree
merge` after doing the main `git subtree split`", so it's weird and
arbitrary that you can't pass `--squash` to `git subtree split --rejoin`
like you can `git subtree merge`. It's weird that `git subtree split
--rejoin` inherits `git subtree merge`'s `--message` but not `--squash`.
Reconcile the situation by just having `split --rejoin` actually just
call `merge` internally (or call `add` instead, as appropriate), so it
can get access to the full `merge` behavior, including `--squash`.
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Tue, 27 Apr 2021 21:17:44 +0000 (15:17 -0600)]
subtree: give the docs a once-over
Just went through the docs looking for anything inaccurate or that can
be improved.
In the '-h' text, in the man page synopsis, and in the man page
description: Normalize the ordering of the list of sub-commands: 'add',
'merge', 'split', 'pull', 'push'. This allows us to kinda separate the
lower-level add/merge/split from the higher-level pull/push.
'-h' text:
- correction: Indicate that split's arg is optional.
- clarity: Emphasize that 'pull' takes the 'add'/'merge' flags.
man page:
- correction: State that all subcommands take options (it seemed to
indicate that only 'split' takes any options other than '-P').
- correction: 'split' only guarantees that the results are identical if
the flags are identical.
- correction: The flag is named '--ignore-joins', not '--ignore-join'.
- completeness: Clarify that 'push' always operates on HEAD, and that
'split' operates on HEAD if no local commit is given.
- clarity: In the description, when listing commands, repeat what their
arguments are. This way the reader doesn't need to flip back and
forth between the command description and the synopsis and the full
description to understand what's being said.
- clarity: In the <variables> used to give command arguments, give
slightly longer, descriptive names. Like <local-commit> instead of
just <commit>.
- clarity: Emphasize that 'pull' takes the 'add'/'merge' flags.
- style: In the synopsis, list options before the subcommand. This
makes things line up and be much more readable when shown
non-monospace (such as in `make html`), and also more closely matches
other man pages (like `git-submodule.txt`).
- style: Use the correct syntax for indicating the options ([<options>]
instead of [OPTIONS]).
- style: In the synopsis, separate 'pull' and 'push' from the other
lower-level commands. I think this helps readability.
- style: Code-quote things in prose that seem like they should be
code-quoted, like '.gitmodules', flags, or full commands.
- style: Minor wording improvements, like more consistent mood (many
of the command descriptions start in the imperative mood and switch
to the indicative mode by the end). That sort of thing.
- style: Capitalize "ID".
- style: Remove the "This option is only valid for XXX command" remarks
from each option, and instead rely on the section headings.
- style: Since that line is getting edited anyway, switch "behaviour" to
American "behavior".
- style: Trim trailing whitespace.
`todo`:
- style: Trim trailing whitespace.
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Tue, 27 Apr 2021 21:17:43 +0000 (15:17 -0600)]
subtree: have $indent actually affect indentation
Currently, the $indent variable is just used to track how deeply we're
nested, and the debug log is indented by things like
debug " foo"
That is: The indentation-level is hard-coded. It used to be that the
code couldn't recurse, so the indentation level could be known
statically, so it made sense to just hard-code it in the
output. However, since 315a84f9aa ("subtree: use commits before rejoins
for splits", 2018-09-28), it can now recurse, and the debug log is
misleading.
So fix that. Indent according to $indent.
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Tue, 27 Apr 2021 21:17:42 +0000 (15:17 -0600)]
subtree: don't let debug and progress output clash
Currently, debug output (triggered by passing '-d') and progress output
stomp on each other. The debug output is just streamed as lines to
stderr, and the progress output is sent to stderr as '%s\r'. When
writing to a file, it is awkward to read and difficult to distinguish
between the debug output and a progress line. When writing to a
terminal the debug lines hide progress lines.
So, when '-d' has been passed, spit out progress as 'progress: %s\n',
instead of as '%s\r', so that it can be detected, and so that the debug
lines don't overwrite the progress when written to a terminal.
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Tue, 27 Apr 2021 21:17:41 +0000 (15:17 -0600)]
subtree: add comments and sanity checks
For each function in subtree, add a usage comment saying what the
arguments are, and add an `assert` checking the number of arguments.
In figuring out each thing's arguments in order to write those comments
and assertions, it turns out that find_existing_splits is written as if
it takes multiple 'revs', but it is in fact only ever passed a single
'rev':
Luke Shumaker [Tue, 27 Apr 2021 21:17:40 +0000 (15:17 -0600)]
subtree: remove duplicate check
`cmd_add` starts with a check that the directory doesn't yet exist.
However, the `main` function performs the exact same check before
calling `cmd_add`. So remove the check from `cmd_add`.
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Tue, 27 Apr 2021 21:17:39 +0000 (15:17 -0600)]
subtree: parse revs in individual cmd_ functions
The main argument parser goes ahead and tries to parse revs to make
things simpler for the sub-command implementations. But, it includes
enough special cases for different sub-commands. And it's difficult
having having to think about "is this info coming from an argument, or a
global variable?". So the main argument parser's effort to make things
"simpler" ends up just making it more confusing and complicated.
Begone with the 'revs' global variable; parse 'rev=$(...)' as needed in
individual 'cmd_*' functions.
Begone with the 'default' global variable. Its would-be value is
knowable just from which function we're in.
Begone with the 'ensure_single_rev' function. Its functionality can be
achieved by passing '--verify' to 'git rev-parse'.
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Tue, 27 Apr 2021 21:17:37 +0000 (15:17 -0600)]
subtree: don't fuss with PATH
Scripts needing to fuss with with adding $(git --exec-prefix) PATH
before loading git-sh-setup is a thing of the past. As far as I can
tell, it's been a thing of the past since since Git v1.2.0 (2006-02-12),
or more specifically, since 77cb17e940 (Exec git programs without using
PATH, 2006-01-10). However, it stuck around in contrib scripts and in
third-party scripts for long enough that it wasn't unusual to see.
Originally `git subtree` didn't fuss with PATH, but when people
(including the original subtree author) had problems, because it was a
common thing to see, it seemed that having subtree fuss with PATH was a
reasonable solution.
Here is an abridged history of fussing with PATH in subtree:
2987e6add3 (Add explicit path of git installation by 'git --exec-path', Gianluca Pacchiella, 2009-08-20)
As pointed out by documentation, the correct use of 'git-sh-setup' is
using $(git --exec-path) to avoid problems with not standard
installations.
33aaa697a2 (Improve patch to use git --exec-path: add to PATH instead, Avery Pennarun, 2009-08-26)
If you (like me) are using a modified git straight out of its source
directory (ie. without installing), then --exec-path isn't actually correct.
Add it to the PATH instead, so if it is correct, it'll work, but if it's
not, we fall back to the previous behaviour.
9c632ea29c ((Hopefully) fix PATH setting for msysgit, Avery Pennarun, 2010-06-24)
Reported by Evan Shaw. The problem is that $(git --exec-path) includes a
'git' binary which is incompatible with the one in /usr/bin; if you run it,
it gives you an error about libiconv2.dll.
+OPATH=$PATH
PATH=$(git --exec-path):$PATH
. git-sh-setup
+PATH=$OPATH # apparently needed for some versions of msysgit
df2302d774 (Another fix for PATH and msysgit, Avery Pennarun, 2010-06-24)
Evan Shaw tells me the previous fix didn't work. Let's use this one
instead, which he says does work.
This fix is kind of wrong because it will run the "correct" git-sh-setup
*after* the one in /usr/bin, if there is one, which could be weird if you
have multiple versions of git installed. But it works on my Linux and his
msysgit, so it's obviously better than what we had before.
-OPATH=$PATH
-PATH=$(git --exec-path):$PATH
+PATH=$PATH:$(git --exec-path)
. git-sh-setup
-PATH=$OPATH # apparently needed for some versions of msysgit
First of all, I disagree with Gianluca's reading of the documentation:
- I haven't gone back to read what the documentation said in 2009, but
in my reading of the 2021 documentation is that it includes "$(git
--exec-path)/" in the synopsis for illustrative purposes, not to say
it's the proper way.
- After being executed by `git`, the git exec path should be the very
first entry in PATH, so it shouldn't matter.
- None of the scripts that are part of git do it that way.
But secondly, the root reason for fussing with PATH seems to be that
Avery didn't know that he needs to set GIT_EXEC_PATH if he's going to
use git from the source directory without installing.
And finally, Evan's issue is clearly just a bug in msysgit. I assume
that msysgit has since fixed the issue, and also msysgit has been
deprecated for 6 years now, so let's drop the workaround for it.
So, remove the line fussing with PATH. However, since subtree *is* in
'contrib/' and it might get installed in funny ways by users
after-the-fact, add a sanity check to the top of the script, checking
that it is installed correctly.
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Tue, 27 Apr 2021 21:17:36 +0000 (15:17 -0600)]
subtree: use "$*" instead of "$@" as appropriate
"$*" is for when you want to concatenate the args together,
whitespace-separated; and "$@" is for when you want them to be separate
strings.
There are several places in subtree that erroneously use $@ when
concatenating args together into an error message.
For instance, if the args are argv[1]="dead" and argv[2]="beef", then
the line
die "You must provide exactly one revision. Got: '$@'"
surely intends to call 'die' with the argument
argv[1]="You must provide exactly one revision. Got: 'dead beef'"
however, because the line used $@ instead of $*, it will actually call
'die' with the arguments
argv[1]="You must provide exactly one revision. Got: 'dead"
argv[2]="beef'"
This isn't a big deal, because 'die' concatenates its arguments together
anyway (using "$*"). But that doesn't change the fact that it was a
mistake to use $@ instead of $*, even though in the end $@ still ended
up doing the right thing.
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Tue, 27 Apr 2021 21:17:32 +0000 (15:17 -0600)]
subtree: drop support for git < 1.7
Suport for Git versions older than 1.7.0 (older than February 2010) was
nice to have when git-subtree lived out-of-tree. But now that it lives
in git.git, it's not necessary to keep around. While it's technically
in contrib, with the standard 'git' packages for common systems
(including Arch Linux and macOS) including git-subtree, it seems
vanishingly likely to me that people are separately installing
git-subtree from git.git alongside an older 'git' install (although it
also seems vanishingly likely that people are still using >11 year old
git installs).
Not that there's much reason to remove it either, it's not much code,
and none of my changes depend on a newer git (to my knowledge, anyway;
I'm not actually testing against older git). I just figure it's an easy
piece of fat to trim, in the journey to making the whole thing easier to
hack on.
"Ignore space change" is probably helpful when viewing this diff.
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Tue, 27 Apr 2021 21:17:31 +0000 (15:17 -0600)]
subtree: more consistent error propagation
Ensure that every $(subshell) that calls a function (as opposed to an
external executable) is followed by `|| exit $?`. Similarly, ensure that
every `cmd | while read; do ... done` loop is followed by `|| exit $?`.
Both of those constructs mean that it can miss `die` calls, and keep
running when it shouldn't.
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Tue, 27 Apr 2021 21:17:30 +0000 (15:17 -0600)]
subtree: don't have loose code outside of a function
Shove all of the loose code inside of a main() function.
This comes down to personal preference more than anything else. A
preference that I've developed over years of maintaining large Bash
scripts, but still a mere personal preference.
In this specific case, it's also moving the `set -- -h`, the `git
rev-parse --parseopt`, and the `. git-sh-setup` to be closer to all
the rest of the argument parsing, which is a readability win on its
own, IMO.
"Ignore space change" is probably helpful when viewing this diff.
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Tue, 27 Apr 2021 21:17:27 +0000 (15:17 -0600)]
subtree: t7900: rename last_commit_message to last_commit_subject
t7900-subtree.sh defines a helper function named last_commit_message.
However, it only returns the subject line of the commit message, not the
entire commit message. So rename it, to make the name less confusing.
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Tue, 27 Apr 2021 21:17:26 +0000 (15:17 -0600)]
subtree: t7900: fix 'verify one file change per commit'
As far as I can tell, this test isn't actually testing anything, because
someone forgot to tack on `--name-only` to `git log`. This seems to
have been the case since the test was first written, back in fa16ab36ad
("test.sh: make sure no commit changes more than one file at a time.",
2009-04-26), unless `git log` used to do that by default and didn't need
the flag back then?
Convincing myself that it's not actually testing anything was tricky,
the code is a little hard to reason about. It can be made a lot simpler
if instead of trying to parse all of the info from a single `git log`,
we're OK calling `git log` from inside of a loop. And it's my opinion
that tests are not the place for clever optimized code.
So, fix and simplify the test, so that it's actually testing something
and is simpler to reason about.
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Tue, 27 Apr 2021 21:17:24 +0000 (15:17 -0600)]
subtree: t7900: use 'test' for string equality
t7900-subtree.sh defines its own `check_equal A B` function, instead of
just using `test A = B` like all of the other tests. Don't be special,
get rid of `check_equal` in favor of `test`.
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Tue, 27 Apr 2021 21:17:23 +0000 (15:17 -0600)]
subtree: t7900: comment subtree_test_create_repo
It's unclear what the purpose of t7900-subtree.sh's
`subtree_test_create_repo` helper function is. It wraps test-lib.sh's,
`test_create_repo` but follows that up by setting log.date=relative. Why
does it set log.date=relative?
My first guess was that at one point the tests required that, but no
longer do, and that the function is now vestigial. I even wrote a patch
to get rid of it and was moments away from `git send-email`ing it.
However, by chance when looking for something else in the history, I
discovered the true reason, from e7aac44ed2 (contrib/subtree: ignore
log.date configuration, 2015-07-21). It's testing that setting
log.date=relative doesn't break `git subtree`, as at one point in the past
that did break `git subtree`.
So, add a comment about this, to avoid future such confusion.
And while at it, go ahead and (1) touch up the function to avoid a
pointless subshell and (2) update the one test that didn't use it.
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Tue, 27 Apr 2021 21:17:21 +0000 (15:17 -0600)]
subtree: t7900: use test-lib.sh's test_count
Use test-lib.sh's `test_count`, instead instead of having
t7900-subtree.sh do its own book-keeping with `subtree_test_count` that
has to be explicitly incremented by calling `next_test`.
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Tue, 27 Apr 2021 21:17:19 +0000 (15:17 -0600)]
.gitignore: ignore 'git-subtree' as a build artifact
Running `make -C contrib/subtree/ test` creates a `git-subtree` executable
in the root of the repo. Add it to the .gitignore so that anyone hacking
on subtree won't have to deal with that noise.
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Rafael Silva [Wed, 21 Apr 2021 19:32:12 +0000 (21:32 +0200)]
repack: avoid loosening promisor objects in partial clones
When `git repack -A -d` is run in a partial clone, `pack-objects`
is invoked twice: once to repack all promisor objects, and once to
repack all non-promisor objects. The latter `pack-objects` invocation
is with --exclude-promisor-objects and --unpack-unreachable, which
loosens all objects unused during this invocation. Unfortunately,
this includes promisor objects.
Because the -d argument to `git repack` subsequently deletes all loose
objects also in packs, these just-loosened promisor objects will be
immediately deleted. However, this extra disk churn is unnecessary in
the first place. For example, in a newly-cloned partial repo that
filters all blob objects (e.g. `--filter=blob:none`), `repack` ends up
unpacking all trees and commits into the filesystem because every
object, in this particular case, is a promisor object. Depending on
the repo size, this increases the disk usage considerably: In my copy
of the linux.git, the object directory peaked 26GB of more disk usage.
In order to avoid this extra disk churn, pass the names of the promisor
packfiles as --keep-pack arguments to the second invocation of
`pack-objects`. This informs `pack-objects` that the promisor objects
are already in a safe packfile and, therefore, do not need to be
loosened.
For testing, we need to validate whether any object was loosened.
However, the "evidence" (loosened objects) is deleted during the
process which prevents us from inspecting the object directory.
Instead, let's teach `pack-objects` to count loosened objects and
emit via trace2 thus allowing inspecting the debug events after the
process is finished. This new event is used on the added regression
test.
Lastly, add a new perf test to evaluate the performance impact
made by this changes (tested on git.git):
Test HEAD^ HEAD
----------------------------------------------------------
5600.3: gc 134.38(41.93+90.95) 7.80(6.72+1.35) -94.2%
For a bigger repository, such as linux.git, the improvement is
even bigger:
Test HEAD^ HEAD
-------------------------------------------------------------------
5600.3: gc 6833.00(918.07+3162.74) 268.79(227.02+39.18) -96.1%
These improvements are particular big because every object in the
newly-cloned partial repository is a promisor object.
Reported-by: SZEDER Gábor <szeder.dev@gmail.com> Helped-by: Jeff King <peff@peff.net> Helped-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Rafael Silva <rafaeloliveira.cs@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Andrzej Hunt [Sun, 25 Apr 2021 14:16:19 +0000 (14:16 +0000)]
builtin/rm: avoid leaking pathspec and seen
parse_pathspec() populates pathspec, hence we need to clear it once it's
no longer needed. seen is xcalloc'd within the same function and
likewise needs to be freed once its no longer needed.
cmd_rm() has multiple early returns, therefore we need to clear or free
as soon as this data is no longer needed, as opposed to doing a cleanup
at the end.
LSAN output from t0020:
Direct leak of 112 byte(s) in 1 object(s) allocated from:
#0 0x49a85d in malloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:145:3
#1 0x9ac0a4 in do_xmalloc wrapper.c:41:8
#2 0x9ac07a in xmalloc wrapper.c:62:9
#3 0x873277 in parse_pathspec pathspec.c:582:2
#4 0x646ffa in cmd_rm builtin/rm.c:266:2
#5 0x4cd91d in run_builtin git.c:467:11
#6 0x4cb5f3 in handle_builtin git.c:719:3
#7 0x4ccf47 in run_argv git.c:808:4
#8 0x4caf49 in cmd_main git.c:939:19
#9 0x69dc0e in main common-main.c:52:11
#10 0x7f948825b349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Indirect leak of 65 byte(s) in 1 object(s) allocated from:
#0 0x49ab79 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0x9ac2a6 in xrealloc wrapper.c:126:8
#2 0x93b14d in strbuf_grow strbuf.c:98:2
#3 0x93ccf6 in strbuf_vaddf strbuf.c:392:3
#4 0x93f726 in xstrvfmt strbuf.c:979:2
#5 0x93f8b3 in xstrfmt strbuf.c:989:8
#6 0x92ad8a in prefix_path_gently setup.c:115:15
#7 0x873a8d in init_pathspec_item pathspec.c:439:11
#8 0x87334f in parse_pathspec pathspec.c:589:3
#9 0x646ffa in cmd_rm builtin/rm.c:266:2
#10 0x4cd91d in run_builtin git.c:467:11
#11 0x4cb5f3 in handle_builtin git.c:719:3
#12 0x4ccf47 in run_argv git.c:808:4
#13 0x4caf49 in cmd_main git.c:939:19
#14 0x69dc0e in main common-main.c:52:11
#15 0x7f948825b349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Indirect leak of 15 byte(s) in 1 object(s) allocated from:
#0 0x486834 in strdup ../projects/compiler-rt/lib/asan/asan_interceptors.cpp:452:3
#1 0x9ac048 in xstrdup wrapper.c:29:14
#2 0x873ba2 in init_pathspec_item pathspec.c:468:20
#3 0x87334f in parse_pathspec pathspec.c:589:3
#4 0x646ffa in cmd_rm builtin/rm.c:266:2
#5 0x4cd91d in run_builtin git.c:467:11
#6 0x4cb5f3 in handle_builtin git.c:719:3
#7 0x4ccf47 in run_argv git.c:808:4
#8 0x4caf49 in cmd_main git.c:939:19
#9 0x69dc0e in main common-main.c:52:11
#10 0x7f948825b349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Direct leak of 1 byte(s) in 1 object(s) allocated from:
#0 0x49a9d2 in calloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:154:3
#1 0x9ac392 in xcalloc wrapper.c:140:8
#2 0x647108 in cmd_rm builtin/rm.c:294:9
#3 0x4cd91d in run_builtin git.c:467:11
#4 0x4cb5f3 in handle_builtin git.c:719:3
#5 0x4ccf47 in run_argv git.c:808:4
#6 0x4caf49 in cmd_main git.c:939:19
#7 0x69dbfe in main common-main.c:52:11
#8 0x7f4fac1b0349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Signed-off-by: Andrzej Hunt <ajrhunt@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Andrzej Hunt [Sun, 25 Apr 2021 14:16:18 +0000 (14:16 +0000)]
builtin/rebase: release git_format_patch_opt too
options.git_format_patch_opt can be populated during cmd_rebase's setup,
and will therefore leak on return. Although we could just UNLEAK all of
options, we choose to strbuf_release() the individual member, which matches
the existing pattern (where we're freeing invidual members of options).
Leak found when running t0021:
Direct leak of 24 byte(s) in 1 object(s) allocated from:
#0 0x49ab79 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0x9ac296 in xrealloc wrapper.c:126:8
#2 0x93b13d in strbuf_grow strbuf.c:98:2
#3 0x93bd3a in strbuf_add strbuf.c:295:2
#4 0x60ae92 in strbuf_addstr strbuf.h:304:2
#5 0x605f17 in cmd_rebase builtin/rebase.c:1759:3
#6 0x4cd91d in run_builtin git.c:467:11
#7 0x4cb5f3 in handle_builtin git.c:719:3
#8 0x4ccf47 in run_argv git.c:808:4
#9 0x4caf49 in cmd_main git.c:939:19
#10 0x69dbfe in main common-main.c:52:11
#11 0x7f66dae91349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 24 byte(s) leaked in 1 allocation(s).
Signed-off-by: Andrzej Hunt <ajrhunt@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Andrzej Hunt [Sun, 25 Apr 2021 14:16:17 +0000 (14:16 +0000)]
builtin/for-each-ref: free filter and UNLEAK sorting.
sorting might be a list allocated in ref_default_sorting() (in this case
it's a fixed single item list, which has nevertheless been xcalloc'd),
or it might be a list allocated in parse_opt_ref_sorting(). In either
case we could free these lists - but instead we UNLEAK as we're at the
end of cmd_for_each_ref. (There's no existing implementation of
clear_ref_sorting(), and writing a loop to free the list seems more
trouble than it's worth.)
filter.with_commit/no_commit are populated via
OPT_CONTAINS/OPT_NO_CONTAINS, both of which create new entries via
parse_opt_commits(), and also need to be free'd or UNLEAK'd. Because
free_commit_list() already exists, we choose to use that over an UNLEAK.
LSAN output from t0041:
Direct leak of 16 byte(s) in 1 object(s) allocated from:
#0 0x49a9d2 in calloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:154:3
#1 0x9ac252 in xcalloc wrapper.c:140:8
#2 0x8a4a55 in ref_default_sorting ref-filter.c:2486:32
#3 0x56c6b1 in cmd_for_each_ref builtin/for-each-ref.c:72:13
#4 0x4cd91d in run_builtin git.c:467:11
#5 0x4cb5f3 in handle_builtin git.c:719:3
#6 0x4ccf47 in run_argv git.c:808:4
#7 0x4caf49 in cmd_main git.c:939:19
#8 0x69dabe in main common-main.c:52:11
#9 0x7f2bdc570349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Direct leak of 16 byte(s) in 1 object(s) allocated from:
#0 0x49a85d in malloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:145:3
#1 0x9abf54 in do_xmalloc wrapper.c:41:8
#2 0x9abf2a in xmalloc wrapper.c:62:9
#3 0x717486 in commit_list_insert commit.c:540:33
#4 0x8644cf in parse_opt_commits parse-options-cb.c:98:2
#5 0x869bb5 in get_value parse-options.c:181:11
#6 0x8677dc in parse_long_opt parse-options.c:378:10
#7 0x8659bd in parse_options_step parse-options.c:817:11
#8 0x867fcd in parse_options parse-options.c:870:10
#9 0x56c62b in cmd_for_each_ref builtin/for-each-ref.c:59:2
#10 0x4cd91d in run_builtin git.c:467:11
#11 0x4cb5f3 in handle_builtin git.c:719:3
#12 0x4ccf47 in run_argv git.c:808:4
#13 0x4caf49 in cmd_main git.c:939:19
#14 0x69dabe in main common-main.c:52:11
#15 0x7f2bdc570349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Signed-off-by: Andrzej Hunt <ajrhunt@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Andrzej Hunt [Sun, 25 Apr 2021 14:16:16 +0000 (14:16 +0000)]
mailinfo: also free strbuf lists when clearing mailinfo
mailinfo.p_hdr_info/s_hdr_info are null-terminated lists of strbuf's,
with entries pointing either to NULL or an allocated strbuf. Therefore
we need to free those strbuf's (and not just the data they contain)
whenever we're done with a given entry. (See handle_header() where those
new strbufs are malloc'd.)
Once we no longer need the list (and not just its entries) we can switch
over to strbuf_list_free() instead of manually iterating over the list,
which takes care of those additional details for us. We can only do this
in clear_mailinfo() - in handle_commit_message() we are only clearing the
array contents but want to reuse the array itself, hence we can't use
strbuf_list_free() there.
However, strbuf_list_free() cannot handle a NULL input, and the lists we
are freeing might be NULL. Therefore we add a NULL check in
strbuf_list_free() to make it safe to use with a NULL input (which is a
pattern used by some of the other *_free() functions around git).
Leak output from t0023:
Direct leak of 72 byte(s) in 3 object(s) allocated from:
#0 0x49a85d in malloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:145:3
#1 0x9ac9f4 in do_xmalloc wrapper.c:41:8
#2 0x9ac9ca in xmalloc wrapper.c:62:9
#3 0x7f6cf7 in handle_header mailinfo.c:205:10
#4 0x7f5abf in check_header mailinfo.c:583:4
#5 0x7f5524 in mailinfo mailinfo.c:1197:3
#6 0x4dcc95 in parse_mail builtin/am.c:1167:6
#7 0x4d9070 in am_run builtin/am.c:1732:12
#8 0x4d5b7a in cmd_am builtin/am.c:2398:3
#9 0x4cd91d in run_builtin git.c:467:11
#10 0x4cb5f3 in handle_builtin git.c:719:3
#11 0x4ccf47 in run_argv git.c:808:4
#12 0x4caf49 in cmd_main git.c:939:19
#13 0x69e43e in main common-main.c:52:11
#14 0x7fc1fadfa349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 72 byte(s) leaked in 3 allocation(s).
Signed-off-by: Andrzej Hunt <ajrhunt@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Andrzej Hunt [Sun, 25 Apr 2021 14:16:15 +0000 (14:16 +0000)]
builtin/checkout: clear pending objects after diffing
add_pending_object() populates rev.pending, we need to take care of
clearing it once we're done.
This code is run close to the end of a checkout, therefore this leak
seems like it would have very little impact. See also LSAN output
from t0020 below:
Direct leak of 2048 byte(s) in 1 object(s) allocated from:
#0 0x49ab79 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0x9acc46 in xrealloc wrapper.c:126:8
#2 0x83e3a3 in add_object_array_with_path object.c:337:3
#3 0x8f672a in add_pending_object_with_path revision.c:329:2
#4 0x8eaeab in add_pending_object_with_mode revision.c:336:2
#5 0x8eae9d in add_pending_object revision.c:342:2
#6 0x5154a0 in show_local_changes builtin/checkout.c:602:2
#7 0x513b00 in merge_working_tree builtin/checkout.c:979:3
#8 0x512cb3 in switch_branches builtin/checkout.c:1242:9
#9 0x50f8de in checkout_branch builtin/checkout.c:1646:9
#10 0x50ba12 in checkout_main builtin/checkout.c:2003:9
#11 0x5086c0 in cmd_checkout builtin/checkout.c:2055:8
#12 0x4cd91d in run_builtin git.c:467:11
#13 0x4cb5f3 in handle_builtin git.c:719:3
#14 0x4ccf47 in run_argv git.c:808:4
#15 0x4caf49 in cmd_main git.c:939:19
#16 0x69e43e in main common-main.c:52:11
#17 0x7f5dd1d50349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 2048 byte(s) leaked in 1 allocation(s). Signed-off-by: Andrzej Hunt <ajrhunt@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Andrzej Hunt [Sun, 25 Apr 2021 14:16:14 +0000 (14:16 +0000)]
builtin/check-ignore: clear_pathspec before returning
parse_pathspec() allocates new memory into pathspec, therefore we need
to free it when we're done.
An UNLEAK would probably be just as good here - but clear_pathspec() is
not much more work so we might as well use it. check_ignore() is either
called once directly from cmd_check_ignore() (in which case the leak
really doesnt matter), or it can be called multiple times in a loop from
check_ignore_stdin_paths(), in which case we're potentially leaking
multiple times - but even in this scenario the leak is so small as to
have no real consequence.
Found while running t0008:
Direct leak of 112 byte(s) in 1 object(s) allocated from:
#0 0x49a85d in malloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:145:3
#1 0x9aca44 in do_xmalloc wrapper.c:41:8
#2 0x9aca1a in xmalloc wrapper.c:62:9
#3 0x873c17 in parse_pathspec pathspec.c:582:2
#4 0x503eb8 in check_ignore builtin/check-ignore.c:90:2
#5 0x5038af in cmd_check_ignore builtin/check-ignore.c:190:17
#6 0x4cd91d in run_builtin git.c:467:11
#7 0x4cb5f3 in handle_builtin git.c:719:3
#8 0x4ccf47 in run_argv git.c:808:4
#9 0x4caf49 in cmd_main git.c:939:19
#10 0x69e43e in main common-main.c:52:11
#11 0x7f18bb0dd349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Indirect leak of 65 byte(s) in 1 object(s) allocated from:
#0 0x49ab79 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0x9acc46 in xrealloc wrapper.c:126:8
#2 0x93baed in strbuf_grow strbuf.c:98:2
#3 0x93d696 in strbuf_vaddf strbuf.c:392:3
#4 0x9400c6 in xstrvfmt strbuf.c:979:2
#5 0x940253 in xstrfmt strbuf.c:989:8
#6 0x92b72a in prefix_path_gently setup.c:115:15
#7 0x87442d in init_pathspec_item pathspec.c:439:11
#8 0x873cef in parse_pathspec pathspec.c:589:3
#9 0x503eb8 in check_ignore builtin/check-ignore.c:90:2
#10 0x5038af in cmd_check_ignore builtin/check-ignore.c:190:17
#11 0x4cd91d in run_builtin git.c:467:11
#12 0x4cb5f3 in handle_builtin git.c:719:3
#13 0x4ccf47 in run_argv git.c:808:4
#14 0x4caf49 in cmd_main git.c:939:19
#15 0x69e43e in main common-main.c:52:11
#16 0x7f18bb0dd349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Indirect leak of 2 byte(s) in 1 object(s) allocated from:
#0 0x486834 in strdup ../projects/compiler-rt/lib/asan/asan_interceptors.cpp:452:3
#1 0x9ac9e8 in xstrdup wrapper.c:29:14
#2 0x874542 in init_pathspec_item pathspec.c:468:20
#3 0x873cef in parse_pathspec pathspec.c:589:3
#4 0x503eb8 in check_ignore builtin/check-ignore.c:90:2
#5 0x5038af in cmd_check_ignore builtin/check-ignore.c:190:17
#6 0x4cd91d in run_builtin git.c:467:11
#7 0x4cb5f3 in handle_builtin git.c:719:3
#8 0x4ccf47 in run_argv git.c:808:4
#9 0x4caf49 in cmd_main git.c:939:19
#10 0x69e43e in main common-main.c:52:11
#11 0x7f18bb0dd349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 179 byte(s) leaked in 3 allocation(s).
Signed-off-by: Andrzej Hunt <ajrhunt@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Andrzej Hunt [Sun, 25 Apr 2021 14:16:13 +0000 (14:16 +0000)]
builtin/bugreport: don't leak prefixed filename
prefix_filename() returns newly allocated memory, and strbuf_addstr()
doesn't take ownership of its inputs. Therefore we have to make sure to
store and free prefix_filename()'s result.
As this leak is in cmd_bugreport(), we could just as well UNLEAK the
prefix - but there's no good reason not to just free it properly. This
leak was found while running t0091, see output below:
Direct leak of 24 byte(s) in 1 object(s) allocated from:
#0 0x49ab79 in realloc /home/abuild/rpmbuild/BUILD/llvm-11.0.0.src/build/../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0x9acc66 in xrealloc wrapper.c:126:8
#2 0x93baed in strbuf_grow strbuf.c:98:2
#3 0x93c6ea in strbuf_add strbuf.c:295:2
#4 0x69f162 in strbuf_addstr ./strbuf.h:304:2
#5 0x69f083 in prefix_filename abspath.c:277:2
#6 0x4fb275 in cmd_bugreport builtin/bugreport.c:146:9
#7 0x4cd91d in run_builtin git.c:467:11
#8 0x4cb5f3 in handle_builtin git.c:719:3
#9 0x4ccf47 in run_argv git.c:808:4
#10 0x4caf49 in cmd_main git.c:939:19
#11 0x69df9e in main common-main.c:52:11
#12 0x7f523a987349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Signed-off-by: Andrzej Hunt <ajrhunt@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Andrzej Hunt [Sun, 25 Apr 2021 14:16:12 +0000 (14:16 +0000)]
branch: FREE_AND_NULL instead of NULL'ing real_ref
real_ref was previously populated by dwim_ref(), which allocates new
memory. We need to make sure to free real_ref when discarding it.
(real_ref is already being freed at the end of create_branch() - but
if we discard it early then it will leak.)
This fixes the following leak found while running t0002-t0099:
Direct leak of 5 byte(s) in 1 object(s) allocated from:
#0 0x486954 in strdup /home/abuild/rpmbuild/BUILD/llvm-11.0.0.src/build/../projects/compiler-rt/lib/asan/asan_interceptors.cpp:452:3
#1 0xdd6484 in xstrdup wrapper.c:29:14
#2 0xc0f658 in expand_ref refs.c:671:12
#3 0xc0ecf1 in repo_dwim_ref refs.c:644:22
#4 0x8b1184 in dwim_ref ./refs.h:162:9
#5 0x8b0b02 in create_branch branch.c:284:10
#6 0x550cbb in update_refs_for_switch builtin/checkout.c:1046:4
#7 0x54e275 in switch_branches builtin/checkout.c:1274:2
#8 0x548828 in checkout_branch builtin/checkout.c:1668:9
#9 0x541306 in checkout_main builtin/checkout.c:2025:9
#10 0x5395fa in cmd_checkout builtin/checkout.c:2077:8
#11 0x4d02a8 in run_builtin git.c:467:11
#12 0x4cbfe9 in handle_builtin git.c:719:3
#13 0x4cf04f in run_argv git.c:808:4
#14 0x4cb85a in cmd_main git.c:939:19
#15 0x820cf6 in main common-main.c:52:11
#16 0x7f30bd9dd349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Signed-off-by: Andrzej Hunt <ajrhunt@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Andrzej Hunt [Sun, 25 Apr 2021 14:16:11 +0000 (14:16 +0000)]
bloom: clear each bloom_key after use
fill_bloom_key() allocates memory into bloom_key, we need to clean that
up once the key is no longer needed.
This leak was found while running t0002-t0099. Although this leak is
happening in code being called from a test-helper, the same code is also
used in various locations around git, and can therefore happen during
normal usage too. Gabor's analysis shows that peak-memory usage during
'git commit-graph write' is reduced on the order of 10% for a selection
of larger repos (along with an even larger reduction if we override
modified path bloom filter limits):
https://lore.kernel.org/git/20210411072651.GF2947267@szeder.dev/
LSAN output:
Direct leak of 308 byte(s) in 11 object(s) allocated from:
#0 0x49a5e2 in calloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:154:3
#1 0x6f4032 in xcalloc wrapper.c:140:8
#2 0x4f2905 in fill_bloom_key bloom.c:137:28
#3 0x4f34c1 in get_or_compute_bloom_filter bloom.c:284:4
#4 0x4cb484 in get_bloom_filter_for_commit t/helper/test-bloom.c:43:11
#5 0x4cb072 in cmd__bloom t/helper/test-bloom.c:97:3
#6 0x4ca7ef in cmd_main t/helper/test-tool.c:121:11
#7 0x4caace in main common-main.c:52:11
#8 0x7f798af95349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 308 byte(s) leaked in 11 allocation(s).
Signed-off-by: Andrzej Hunt <ajrhunt@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Andrzej Hunt [Sun, 25 Apr 2021 14:16:10 +0000 (14:16 +0000)]
ls-files: free max_prefix when done
common_prefix() returns a new string, which we store in max_prefix -
this string needs to be freed to avoid a leak. This leak is happening
in cmd_ls_files, hence is of no real consequence - an UNLEAK would be
just as good, but we might as well free the string properly.
Leak found while running t0002, see output below:
Direct leak of 8 byte(s) in 1 object(s) allocated from:
#0 0x49a85d in malloc /home/abuild/rpmbuild/BUILD/llvm-11.0.0.src/build/../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:145:3
#1 0x9ab1b4 in do_xmalloc wrapper.c:41:8
#2 0x9ab248 in do_xmallocz wrapper.c:75:8
#3 0x9ab22a in xmallocz wrapper.c:83:9
#4 0x9ab2d7 in xmemdupz wrapper.c:99:16
#5 0x78d6a4 in common_prefix dir.c:191:15
#6 0x5aca48 in cmd_ls_files builtin/ls-files.c:669:16
#7 0x4cd92d in run_builtin git.c:453:11
#8 0x4cb5fa in handle_builtin git.c:704:3
#9 0x4ccf57 in run_argv git.c:771:4
#10 0x4caf49 in cmd_main git.c:902:19
#11 0x69ce2e in main common-main.c:52:11
#12 0x7f64d4d94349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Signed-off-by: Andrzej Hunt <ajrhunt@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Andrzej Hunt [Sun, 25 Apr 2021 14:16:09 +0000 (14:16 +0000)]
wt-status: fix multiple small leaks
rev.prune_data is populated (in multiple functions) via copy_pathspec,
and therefore needs to be cleared after running the diff in those
functions.
rev(_info).pending is populated indirectly via setup_revisions, and also
needs to be cleared once diffing is done.
These leaks were found while running t0008 or t0021. The rev.prune_data
leaks are small (80B) but noisy, hence I won't bother including their
logs - the rev.pending leaks are bigger, and can happen early in the
course of other commands, and therefore possibly more valuable to fix -
see example log from a rebase below:
Direct leak of 2048 byte(s) in 1 object(s) allocated from:
#0 0x49ab79 in realloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0x9ac2a6 in xrealloc wrapper.c:126:8
#2 0x83da03 in add_object_array_with_path object.c:337:3
#3 0x8f5d8a in add_pending_object_with_path revision.c:329:2
#4 0x8ea50b in add_pending_object_with_mode revision.c:336:2
#5 0x8ea4fd in add_pending_object revision.c:342:2
#6 0x8ea610 in add_head_to_pending revision.c:354:2
#7 0x9b55f5 in has_uncommitted_changes wt-status.c:2474:2
#8 0x9b58c4 in require_clean_work_tree wt-status.c:2553:6
#9 0x606bcc in cmd_rebase builtin/rebase.c:1970:6
#10 0x4cd91d in run_builtin git.c:467:11
#11 0x4cb5f3 in handle_builtin git.c:719:3
#12 0x4ccf47 in run_argv git.c:808:4
#13 0x4caf49 in cmd_main git.c:939:19
#14 0x69dc0e in main common-main.c:52:11
#15 0x7f2d18909349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Indirect leak of 5 byte(s) in 1 object(s) allocated from:
#0 0x486834 in strdup ../projects/compiler-rt/lib/asan/asan_interceptors.cpp:452:3
#1 0x9ac048 in xstrdup wrapper.c:29:14
#2 0x83da8d in add_object_array_with_path object.c:349:17
#3 0x8f5d8a in add_pending_object_with_path revision.c:329:2
#4 0x8ea50b in add_pending_object_with_mode revision.c:336:2
#5 0x8ea4fd in add_pending_object revision.c:342:2
#6 0x8ea610 in add_head_to_pending revision.c:354:2
#7 0x9b55f5 in has_uncommitted_changes wt-status.c:2474:2
#8 0x9b58c4 in require_clean_work_tree wt-status.c:2553:6
#9 0x606bcc in cmd_rebase builtin/rebase.c:1970:6
#10 0x4cd91d in run_builtin git.c:467:11
#11 0x4cb5f3 in handle_builtin git.c:719:3
#12 0x4ccf47 in run_argv git.c:808:4
#13 0x4caf49 in cmd_main git.c:939:19
#14 0x69dc0e in main common-main.c:52:11
#15 0x7f2d18909349 in __libc_start_main (/lib64/libc.so.6+0x24349)
SUMMARY: AddressSanitizer: 2053 byte(s) leaked in 2 allocation(s).
Signed-off-by: Andrzej Hunt <ajrhunt@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Andrzej Hunt [Sun, 25 Apr 2021 14:16:08 +0000 (14:16 +0000)]
revision: free remainder of old commit list in limit_list
limit_list() iterates over the original revs->commits list, and consumes
many of its entries via pop_commit. However we might stop iterating over
the list early (e.g. if we realise that the rest of the list is
uninteresting). If we do stop iterating early, list will be pointing to
the unconsumed portion of revs->commits - and we need to free this list
to avoid a leak. (revs->commits itself will be an invalid pointer: it
will have been free'd during the first pop_commit.)
However the list pointer is later reused to iterate over our new list,
but only for the limiting_can_increase_treesame() branch. We therefore
need to introduce a new variable for that branch - and while we're here
we can rename the original list to original_list as that makes its
purpose more obvious.
This leak was found while running t0090. It's not likely to be very
impactful, but it can happen quite early during some checkout
invocations, and hence seems to be worth fixing:
Direct leak of 16 byte(s) in 1 object(s) allocated from:
#0 0x49a85d in malloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:145:3
#1 0x9ac084 in do_xmalloc wrapper.c:41:8
#2 0x9ac05a in xmalloc wrapper.c:62:9
#3 0x7175d6 in commit_list_insert commit.c:540:33
#4 0x71800f in commit_list_insert_by_date commit.c:604:9
#5 0x8f8d2e in process_parents revision.c:1128:5
#6 0x8f2f2c in limit_list revision.c:1418:7
#7 0x8f210e in prepare_revision_walk revision.c:3577:7
#8 0x514170 in orphaned_commit_warning builtin/checkout.c:1185:6
#9 0x512f05 in switch_branches builtin/checkout.c:1250:3
#10 0x50f8de in checkout_branch builtin/checkout.c:1646:9
#11 0x50ba12 in checkout_main builtin/checkout.c:2003:9
#12 0x5086c0 in cmd_checkout builtin/checkout.c:2055:8
#13 0x4cd91d in run_builtin git.c:467:11
#14 0x4cb5f3 in handle_builtin git.c:719:3
#15 0x4ccf47 in run_argv git.c:808:4
#16 0x4caf49 in cmd_main git.c:939:19
#17 0x69dc0e in main common-main.c:52:11
#18 0x7faaabd0e349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Indirect leak of 48 byte(s) in 3 object(s) allocated from:
#0 0x49a85d in malloc ../projects/compiler-rt/lib/asan/asan_malloc_linux.cpp:145:3
#1 0x9ac084 in do_xmalloc wrapper.c:41:8
#2 0x9ac05a in xmalloc wrapper.c:62:9
#3 0x717de6 in commit_list_append commit.c:1609:35
#4 0x8f1f9b in prepare_revision_walk revision.c:3554:12
#5 0x514170 in orphaned_commit_warning builtin/checkout.c:1185:6
#6 0x512f05 in switch_branches builtin/checkout.c:1250:3
#7 0x50f8de in checkout_branch builtin/checkout.c:1646:9
#8 0x50ba12 in checkout_main builtin/checkout.c:2003:9
#9 0x5086c0 in cmd_checkout builtin/checkout.c:2055:8
#10 0x4cd91d in run_builtin git.c:467:11
#11 0x4cb5f3 in handle_builtin git.c:719:3
#12 0x4ccf47 in run_argv git.c:808:4
#13 0x4caf49 in cmd_main git.c:939:19
#14 0x69dc0e in main common-main.c:52:11
#15 0x7faaabd0e349 in __libc_start_main (/lib64/libc.so.6+0x24349)
Signed-off-by: Andrzej Hunt <ajrhunt@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
brian m. carlson [Mon, 26 Apr 2021 01:03:01 +0000 (01:03 +0000)]
hex: print objects using the hash algorithm member
Now that all code paths correctly set the hash algorithm member of
struct object_id, write an object's hex representation using the hash
algorithm member embedded in it.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
brian m. carlson [Mon, 26 Apr 2021 01:03:00 +0000 (01:03 +0000)]
hex: default to the_hash_algo on zero algorithm value
There are numerous places in the codebase where we assume we can
initialize data by zeroing all its bytes. However, when we do that with
a struct object_id, it leaves the structure with a zero value for the
algorithm, which is invalid.
We could forbid this pattern and require that all struct object_id
instances be initialized using oidclr, but this seems burdensome and
it's unnatural to most C programmers. Instead, if the algorithm is
zero, assume we wanted to use the default hash algorithm instead.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
brian m. carlson [Mon, 26 Apr 2021 01:02:59 +0000 (01:02 +0000)]
builtin/pack-objects: avoid using struct object_id for pack hash
We use struct object_id for the names of objects. It isn't intended to
be used for other hash values that don't name objects such as the pack
hash.
Because struct object_id will soon need to have its algorithm member
set, using it in this code path would mean that we didn't set that
member, only the hash member, which would result in a crash. For both
of these reasons, switch to using an unsigned char array of size
GIT_MAX_RAWSZ.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
brian m. carlson [Mon, 26 Apr 2021 01:02:58 +0000 (01:02 +0000)]
commit-graph: don't store file hashes as struct object_id
The idea behind struct object_id is that it is supposed to represent the
identifier of a standard Git object or a special pseudo-object like the
all-zeros object ID. In this case, we have file hashes, which, while
similar, are distinct from the identifiers of objects.
Switch these code paths to use an unsigned char array. This is both
more logically consistent and it means that we need not set the
algorithm identifier for the struct object_id.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
brian m. carlson [Mon, 26 Apr 2021 01:02:57 +0000 (01:02 +0000)]
builtin/show-index: set the algorithm for object IDs
In most cases, when we load the hash of an object into a struct
object_id, we load it using one of the oid* or *_oid_hex functions.
However, for git show-index, we read it in directly using fread. As a
consequence, set the algorithm correctly so the objects can be used
correctly both now and in the future.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
brian m. carlson [Mon, 26 Apr 2021 01:02:56 +0000 (01:02 +0000)]
hash: provide per-algorithm null OIDs
Up until recently, object IDs did not have an algorithm member, only a
hash. Consequently, it was possible to share one null (all-zeros)
object ID among all hash algorithms. Now that we're going to be
handling objects from multiple hash algorithms, it's important to make
sure that all object IDs have a correct algorithm field.
Introduce a per-algorithm null OID, and add it to struct hash_algo.
Introduce a wrapper function as well, and use it everywhere we used to
use the null_oid constant.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
brian m. carlson [Mon, 26 Apr 2021 01:02:55 +0000 (01:02 +0000)]
hash: set, copy, and use algo field in struct object_id
Now that struct object_id has an algorithm field, we should populate it.
This will allow us to handle object IDs in any supported algorithm and
distinguish between them. Ensure that the field is written whenever we
write an object ID by storing it explicitly every time we write an
object. Set values for the empty blob and tree values as well.
In addition, use the algorithm field to compare object IDs. Note that
because we zero-initialize struct object_id in many places throughout
the codebase, we default to the default algorithm in cases where the
algorithm field is zero rather than explicitly initialize all of those
locations.
This leads to a branch on every comparison, but the alternative is to
compare the entire buffer each time and padding the buffer for SHA-1.
That alternative ranges up to 3.9% worse than this approach on the perf
t0001, t1450, and t1451.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
brian m. carlson [Mon, 26 Apr 2021 01:02:54 +0000 (01:02 +0000)]
builtin/pack-redundant: avoid casting buffers to struct object_id
Now that we need our instances of struct object_id to be zero padded, we
can no longer cast unsigned char buffers to be pointers to struct
object_id. This file reads data out of the pack objects and then
inserts it directly into a linked list item which is a pointer to struct
object_id. Instead, let's have the linked list item hold its own struct
object_id and copy the data into it.
In addition, since these are not really pointers to struct object_id,
stop passing them around as such, and call them what they really are:
pointers to unsigned char.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
brian m. carlson [Mon, 26 Apr 2021 01:02:53 +0000 (01:02 +0000)]
Use the final_oid_fn to finalize hashing of object IDs
When we're hashing a value which is going to be an object ID, we want to
zero-pad that value if necessary. To do so, use the final_oid_fn
instead of the final_fn anytime we're going to create an object ID to
ensure we perform this operation.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
brian m. carlson [Mon, 26 Apr 2021 01:02:52 +0000 (01:02 +0000)]
hash: add a function to finalize object IDs
To avoid the penalty of having to branch in hash comparison functions,
we'll want to always compare the full hash member in a struct object_id,
which will require that SHA-1 object IDs be zero-padded. To do so, add
a function which finalizes a hash context and writes it into an object
ID that performs this padding.
Move the definition of struct object_id and the constant definitions
higher up so we they are available for us to use.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
brian m. carlson [Mon, 26 Apr 2021 01:02:51 +0000 (01:02 +0000)]
http-push: set algorithm when reading object ID
In most places in the codebase, we use oidread to properly read an
object ID into a struct object_id. However, in the HTTP code, we end up
needing to parse a loose object path with a slash in it, so we can't do
that. Let's instead explicitly set the algorithm in this function so we
can rely on it in the future.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
brian m. carlson [Mon, 26 Apr 2021 01:02:50 +0000 (01:02 +0000)]
Always use oidread to read into struct object_id
In the future, we'll want oidread to automatically set the hash
algorithm member for an object ID we read into it, so ensure we use
oidread instead of hashcpy everywhere we're copying a hash value into a
struct object_id.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
brian m. carlson [Mon, 26 Apr 2021 01:02:49 +0000 (01:02 +0000)]
hash: add an algo member to struct object_id
Now that we're working with multiple hash algorithms in the same repo,
it's best if we label each object ID with its algorithm so we can
determine how to format a given object ID. Add a member called algo to
struct object_id.
Performance testing on object ID-heavy workloads doesn't reveal a clear
change in performance. Out of performance tests t0001 and t1450, there
are slight variations in performance both up and down, but all
measurements are within the margin of error.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
pretty tests: give --date/format tests a better description
Change the description for the --date/format equivalency tests added
in 466fb6742d7 (pretty: provide a strict ISO 8601 date format,
2014-08-29) and 0df621172d8 (pretty: provide short date format,
2019-11-19) to be more meaningful.
This allows us to reword the comment added in the former commit to
refer to both tests, and any other future test, such as the in-flight
--date=human format being proposed in [1].
Change a needlessly complex test for the %aI/%cI date
formats (iso-strict) added in 466fb6742d7 (pretty: provide a strict
ISO 8601 date format, 2014-08-29) to instead use the same pattern used
to test %as/%cs since 0df621172d8 (pretty: provide short date format,
2019-11-19).
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Denton Liu [Thu, 22 Apr 2021 10:00:51 +0000 (03:00 -0700)]
git-completion.bash: use $__git_cmd_idx in more places
With the introduction of the $__git_cmd_idx variable in e94fb44042
(git-completion.bash: pass $__git_subcommand_idx from __git_main(),
2021-03-24), completion functions were able to know the index at which
the git command is listed, allowing them to skip options that are given
to the underlying git itself, not the corresponding command (e.g.
`-C asdf` in `git -C asdf branch`).
While most of the changes here are self-explanatory, some bear further
explanation.
For the __git_find_on_cmdline() and __git_find_last_on_cmdline() pair of
functions, these functions are only ever called in the context of a git
command completion function. These functions will only care about words
after the command so we can safely ignore the words before this.
For _git_worktree(), this change is technically a no-op (once the
__git_find_last_on_cmdline change is also applied). It was in poor style
to have hard-coded on the index right after `worktree`. In case
`git worktree` were to ever learn to accept options, the current
situation would be inflexible.
Signed-off-by: Denton Liu <liu.denton@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Denton Liu [Thu, 22 Apr 2021 10:00:50 +0000 (03:00 -0700)]
git-completion.bash: rename to $__git_cmd_idx
In e94fb44042 (git-completion.bash: pass $__git_subcommand_idx from
__git_main(), 2021-03-24), the $__git_subcommand_idx variable was
introduced. Naming it after the index of the subcommand is needlessly
confusing as, when this variable is used, it is in the completion
functions for commands (e.g. _git_remote()) where for `git remote add`,
the `remote` is referred to as the command and `add` is referred to as
the subcommand.
Rename this variable so that it's obvious it's about git commands. While
we're at it, shorten up its name so that it's still readable without
being a handful to type.
Signed-off-by: Denton Liu <liu.denton@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
t1300: fix unset of GIT_CONFIG_NOSYSTEM leaking into subsequent tests
In order to test whether the new GIT_CONFIG_SYSTEM environment variable
behaves as expected, we unset GIT_CONFIG_NOSYSTEM in one of our tests in
t1300. But because tests are not executed in a subshell, this unset
leaks into all subsequent tests and may thus cause them to fail in some
environments. These failures are easily reproducable with `make
prefix=/root test`.
Fix the issue by not using `sane_unset GIT_CONFIG_NOSYSTEM`, but instead
just manually add it to the environment of the two command invocations
which need it.
Reported-by: SZEDER Gábor <szeder.dev@gmail.com> Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano [Wed, 21 Apr 2021 00:23:36 +0000 (17:23 -0700)]
Merge branch 'ab/usage-error-docs'
Documentation updates, with unrelated comment updates, too.
* ab/usage-error-docs:
api docs: document that BUG() emits a trace2 error event
api docs: document BUG() in api-error-handling.txt
usage.c: don't copy/paste the same comment three times
When "git pack-objects" makes a literal copy of a part of existing
packfile using the reachability bitmaps, its update to the progress
meter was broken.
* jk/pack-objects-bitmap-progress-fix:
pack-objects: update "nr_seen" progress based on pack-reused count
Junio C Hamano [Wed, 21 Apr 2021 00:23:34 +0000 (17:23 -0700)]
Merge branch 'ab/userdiff-tests'
A bit of code clean-up and a lot of test clean-up around userdiff
area.
* ab/userdiff-tests:
blame tests: simplify userdiff driver test
blame tests: don't rely on t/t4018/ directory
userdiff: remove support for "broken" tests
userdiff tests: list builtin drivers via test-tool
userdiff tests: explicitly test "default" pattern
userdiff: add and use for_each_userdiff_driver()
userdiff style: normalize pascal regex declaration
userdiff style: declare patterns with consistent style
userdiff style: re-order drivers in alphabetical order
Denton Liu [Tue, 20 Apr 2021 09:19:47 +0000 (02:19 -0700)]
git-completion.bash: separate some commands onto their own line
In e94fb44042 (git-completion.bash: pass $__git_subcommand_idx from
__git_main(), 2021-03-24), a line was introduced which contained
multiple statements. This is difficult to read so break it into multiple
lines.
While we're at it, follow this convention for the rest of the
__git_main() and break up lines that contain multiple statements.
Signed-off-by: Denton Liu <liu.denton@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
AFAICT parsing the output of `git diff --name-only master...feature`
is the intended way of programmatically getting the list of files
modified
by a feature branch. It is impossible to parse text unless you know what
encoding it is in. The output encoding of diff --name-only and
ZheNing Hu [Tue, 20 Apr 2021 16:52:11 +0000 (16:52 +0000)]
ref-filter: reuse output buffer
When we use `git for-each-ref`, every ref will allocate
its own output strbuf and error strbuf. But we can reuse
the final strbuf for each step ref's output. The error
buffer will also be reused, despite the fact that the git
will exit when `format_ref_array_item()` return a non-zero
value and output the contents of the error buffer.
The performance for `git for-each-ref` on the Git repository
itself with performance testing tool `hyperfine` changes from
23.7 ms ± 0.9 ms to 22.2 ms ± 1.0 ms. Optimization is relatively
minor.
At the same time, we apply this optimization to `git tag -l`
and `git branch -l`.
This approach is similar to the one used by 79ed0a5
(cat-file: use a single strbuf for all output, 2018-08-14)
to speed up the cat-file builtin.
Helped-by: Junio C Hamano <gitster@pobox.com> Helped-by: Jeff King <peff@peff.net> Helped-by: René Scharfe <l.s.r@web.de> Signed-off-by: ZheNing Hu <adlternative@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
ZheNing Hu [Mon, 19 Apr 2021 11:28:44 +0000 (11:28 +0000)]
ref-filter: get rid of show_ref_array_item
Inlining the exported function `show_ref_array_item()`,
which is not providing the right level of abstraction,
simplifies the API and can unlock improvements at the
former call sites.
Helped-by: René Scharfe <l.s.r@web.de> Signed-off-by: ZheNing Hu <adlternative@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Co-authored-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br> Signed-off-by: Junio C Hamano <gitster@pobox.com>
config: allow overriding of global and system configuration
In order to have git run in a fully controlled environment without any
misconfiguration, it may be desirable for users or scripts to override
global- and system-level configuration files. We already have a way of
doing this, which is to unset both HOME and XDG_CONFIG_HOME environment
variables and to set `GIT_CONFIG_NOGLOBAL=true`. This is quite kludgy,
and unsetting the first two variables likely has an impact on other
executables spawned by such a script.
The obvious way to fix this would be to introduce `GIT_CONFIG_NOGLOBAL`
as an equivalent to `GIT_CONFIG_NOSYSTEM`. But in the past, it has
turned out that this design is inflexible: we cannot test system-level
parsing of the git configuration in our test harness because there is no
way to change its location, so all tests run with `GIT_CONFIG_NOSYSTEM`
set.
Instead of doing the same mistake with `GIT_CONFIG_NOGLOBAL`, introduce
two new variables `GIT_CONFIG_GLOBAL` and `GIT_CONFIG_SYSTEM`:
- If unset, git continues to use the usual locations.
- If set to a specific path, we skip reading the normal
configuration files and instead take the path. By setting the path
to `/dev/null`, no configuration will be loaded for the respective
level.
This implements the usecase where we want to execute code in a sanitized
environment without any potential misconfigurations via `/dev/null`, but
is more flexible and allows for more usecases than simply adding
`GIT_CONFIG_NOGLOBAL`.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
config: unify code paths to get global config paths
There's two callsites which assemble global config paths, once in the
config loading code and once in the git-config(1) builtin. We're about
to implement a way to override global config paths via an environment
variable which would require us to adjust both sites.
Unify both code paths into a single `git_global_config()` function which
returns both paths for `~/.gitconfig` and the XDG config file. This will
make the subsequent patch which introduces the new envvar easier to
implement.
No functional changes are expected from this patch.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The `git_etc_gitconfig()` function retrieves the system-level path of
the configuration file. We're about to introduce a way to override it
via an environment variable, at which point the name of this function
would start to become misleading.
Rename the function to `git_system_config()` as a preparatory step.
While at it, the function is also refactored to pass memory ownership to
the caller. This is done to better match semantics of
`git_global_config()`, which is going to be introduced in the next
commit.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
When providing an object filter, it is currently impossible to also
filter provided items. E.g. when executing `git rev-list HEAD` , the
commit this reference points to will be treated as user-provided and is
thus excluded from the filtering mechanism. This makes it harder than
necessary to properly use the new `--filter=object:type` filter given
that even if the user wants to only see blobs, he'll still see commits
of provided references.
Improve this by introducing a new `--filter-provided-objects` option
to the git-rev-parse(1) command. If given, then all user-provided
references will be subject to filtering.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
When the user has multiple objects filters specified, then this is
internally represented by having a "combined" filter. These combined
filters aren't yet supported by bitmap indices and can thus not be
accelerated.
Fix this by implementing support for these combined filters. The
implementation is quite trivial: when there's a combined filter, we
simply recurse into `filter_bitmap()` for all of the sub-filters.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The preceding commit has added a new object filter for git-rev-list(1)
which allows to filter objects by type. Implement the equivalent filter
for packfile bitmaps so that we can answer these queries fast.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
While it already is possible to filter objects by some criteria in
git-rev-list(1), it is not yet possible to filter out only a specific
type of objects. This makes some filters less useful. The `blob:limit`
filter for example filters blobs such that only those which are smaller
than the given limit are returned. But it is unfit to ask only for these
smallish blobs, given that git-rev-list(1) will continue to print tags,
commits and trees.
Now that we have the infrastructure in place to also filter tags and
commits, we can improve this situation by implementing a new filter
which selects objects based on their type. Above query can thus
trivially be implemented with the following command:
Furthermore, this filter allows to optimize for certain other cases: if
for example only tags or commits have been selected, there is no need to
walk down trees.
The new filter is not yet supported in bitmaps. This is going to be
implemented in a subsequent commit.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Make parallel checkout configurable by introducing two new settings:
checkout.workers and checkout.thresholdForParallelism. The first defines
the number of workers (where one means sequential checkout), and the
second defines the minimum number of entries to attempt parallel
checkout.
To decide the default value for checkout.workers, the parallel version
was benchmarked during three operations in the linux repo, with cold
cache: cloning v5.8, checking out v5.8 from v2.6.15 (checkout I) and
checking out v5.8 from v5.7 (checkout II). The four tables below show
the mean run times and standard deviations for 5 runs in: a local file
system on SSD, a local file system on HDD, a Linux NFS server, and
Amazon EFS (all on Linux). Each parallel checkout test was executed with
the number of workers that brings the best overall results in that
environment.
Local SSD:
Sequential 10 workers Speedup
Clone 8.805 s ± 0.043 s 3.564 s ± 0.041 s 2.47 ± 0.03
Checkout I 9.678 s ± 0.057 s 4.486 s ± 0.050 s 2.16 ± 0.03
Checkout II 5.034 s ± 0.072 s 3.021 s ± 0.038 s 1.67 ± 0.03
Local HDD:
Sequential 10 workers Speedup
Clone 32.288 s ± 0.580 s 30.724 s ± 0.522 s 1.05 ± 0.03
Checkout I 54.172 s ± 7.119 s 54.429 s ± 6.738 s 1.00 ± 0.18
Checkout II 40.465 s ± 2.402 s 38.682 s ± 1.365 s 1.05 ± 0.07
Linux NFS server (v4.1, on EBS, single availability zone):
Sequential 32 workers Speedup
Clone 240.368 s ± 6.347 s 57.349 s ± 0.870 s 4.19 ± 0.13
Checkout I 242.862 s ± 2.215 s 58.700 s ± 0.904 s 4.14 ± 0.07
Checkout II 65.751 s ± 1.577 s 23.820 s ± 0.407 s 2.76 ± 0.08
EFS (v4.1, replicated over multiple availability zones):
Sequential 32 workers Speedup
Clone 922.321 s ± 2.274 s 210.453 s ± 3.412 s 4.38 ± 0.07
Checkout I 1011.300 s ± 7.346 s 297.828 s ± 0.964 s 3.40 ± 0.03
Checkout II 294.104 s ± 1.836 s 126.017 s ± 1.190 s 2.33 ± 0.03
The above benchmarks show that parallel checkout is most effective on
repositories located on an SSD or over a distributed file system. For
local file systems on spinning disks, and/or older machines, the
parallelism does not always bring a good performance. For this reason,
the default value for checkout.workers is one, a.k.a. sequential
checkout.
To decide the default value for checkout.thresholdForParallelism,
another benchmark was executed in the "Local SSD" setup, where parallel
checkout showed to be beneficial. This time, we compared the runtime of
a `git checkout -f`, with and without parallelism, after randomly
removing an increasing number of files from the Linux working tree. The
"sequential fallback" column below corresponds to the executions where
checkout.workers was 10 but checkout.thresholdForParallelism was equal
to the number of to-be-updated files plus one (so that we end up writing
sequentially). Each test case was sampled 15 times, and each sample had
a randomly different set of files removed. Here are the results:
sequential fallback 10 workers speedup
10 files 772.3 ms ± 12.6 ms 769.0 ms ± 13.6 ms 1.00 ± 0.02
20 files 780.5 ms ± 15.8 ms 775.2 ms ± 9.2 ms 1.01 ± 0.02
50 files 806.2 ms ± 13.8 ms 767.4 ms ± 8.5 ms 1.05 ± 0.02
100 files 833.7 ms ± 21.4 ms 750.5 ms ± 16.8 ms 1.11 ± 0.04
200 files 897.6 ms ± 30.9 ms 730.5 ms ± 14.7 ms 1.23 ± 0.05
500 files 1035.4 ms ± 48.0 ms 677.1 ms ± 22.3 ms 1.53 ± 0.09
1000 files 1244.6 ms ± 35.6 ms 654.0 ms ± 38.3 ms 1.90 ± 0.12
2000 files 1488.8 ms ± 53.4 ms 658.8 ms ± 23.8 ms 2.26 ± 0.12
From the above numbers, 100 files seems to be a reasonable default value
for the threshold setting.
Note: Up to 1000 files, we observe a drop in the execution time of the
parallel code with an increase in the number of files. This is a rather
odd behavior, but it was observed in multiple repetitions. Above 1000
files, the execution time increases according to the number of files, as
one would expect.
About the test environments: Local SSD tests were executed on an
i7-7700HQ (4 cores with hyper-threading) running Manjaro Linux. Local
HDD tests were executed on an Intel(R) Xeon(R) E3-1230 (also 4 cores
with hyper-threading), HDD Seagate Barracuda 7200.14 SATA 3.1, running
Debian. NFS and EFS tests were executed on an Amazon EC2 c5n.xlarge
instance, with 4 vCPUs. The Linux NFS server was running on a m6g.large
instance with 2 vCPUSs and a 1 TB EBS GP2 volume. Before each timing,
the linux repository was removed (or checked out back to its previous
state), and `sync && sysctl vm.drop_caches=3` was executed.
Co-authored-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Use multiple worker processes to distribute the queued entries and call
write_pc_item() in parallel for them. The items are distributed
uniformly in contiguous chunks. This minimizes the chances of two
workers writing to the same directory simultaneously, which could affect
performance due to lock contention in the kernel. Work stealing (or any
other format of re-distribution) is not implemented yet.
The protocol between the main process and the workers is quite simple.
They exchange binary messages packed in pkt-line format, and use
PKT-FLUSH to mark the end of input (from both sides). The main process
starts the communication by sending N pkt-lines, each corresponding to
an item that needs to be written. These packets contain all the
necessary information to load, smudge, and write the blob associated
with each item. Then it waits for the worker to send back N pkt-lines
containing the results for each item. The resulting packet must contain:
the identification number of the item that it refers to, the status of
the operation, and the lstat() data gathered after writing the file (iff
the operation was successful).
For now, checkout always uses a hardcoded value of 2 workers, only to
demonstrate that the parallel checkout framework correctly divides and
writes the queued entries. The next patch will add user configurations
and define a more reasonable default, based on tests with the said
settings.
Co-authored-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Co-authored-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br> Signed-off-by: Junio C Hamano <gitster@pobox.com>
unpack-trees: add basic support for parallel checkout
This new interface allows us to enqueue some of the entries being
checked out to later uncompress them, apply in-process filters, and
write out the files in parallel. For now, the parallel checkout
machinery is enabled by default and there is no user configuration, but
run_parallel_checkout() just writes the queued entries in sequence
(without spawning additional workers). The next patch will actually
implement the parallelism and, later, we will make it configurable.
Note that, to avoid potential data races, not all entries are eligible
for parallel checkout. Also, paths that collide on disk (e.g.
case-sensitive paths in case-insensitive file systems), are detected by
the parallel checkout code and skipped, so that they can be safely
sequentially handled later. The collision detection works like the
following:
- If the collision was at basename (e.g. 'a/b' and 'a/B'), the framework
detects it by looking for EEXIST and EISDIR errors after an
open(O_CREAT | O_EXCL) failure.
- If the collision was at dirname (e.g. 'a/b' and 'A'), it is detected
at the has_dirs_only_path() check, which is done for the leading path
of each item in the parallel checkout queue.
Both verifications rely on the fact that, before enqueueing an entry for
parallel checkout, checkout_entry() makes sure that there is no file at
the entry's path and that its leading components are all real
directories. So, any later change in these conditions indicates that
there was a collision (either between two parallel-eligible entries or
between an eligible and an ineligible one).
After all parallel-eligible entries have been processed, the collided
(and thus, skipped) entries are sequentially fed to checkout_entry()
again. This is similar to the way the current code deals with
collisions, overwriting the previously checked out entries with the
subsequent ones. The only difference is that, since we no longer create
the files in the same order that they appear on index, we are not able
to determine which of the colliding entries will survive on disk (for
the classic code, it is always the last entry).
Co-authored-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Co-authored-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Split set_diff_merges() into separate parsing and execution functions,
the former to be reused for parsing of configuration values later in
the patch series.
Signed-off-by: Sergey Organov <sorganov@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>