Commit Graph

68958 Commits

Author SHA1 Message Date
Ævar Arnfjörð Bjarmason
e84a26e32f unpack-file: fix ancient leak in create_temp_file()
Fix a leak that's been with us since 3407bb4940 (Add "unpack-file"
helper that unpacks a sha1 blob into a tmpfile., 2005-04-18). See
00c8fd493a (cat-file: use streaming API to print blobs, 2012-03-07)
for prior art which shows the same API pattern, i.e. free()-ing the
result of read_object_file() after it's used.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-21 12:32:48 +09:00
Ævar Arnfjörð Bjarmason
b6046abc0c built-ins & libs & helpers: add/move destructors, fix leaks
Fix various leaks in built-ins, libraries and a test helper here we
were missing a call to strbuf_release(), string_list_clear() etc, or
were calling them after a potential "return".

Comments on individual changes:

- builtin/checkout.c: Fix a memory leak that was introduced in [1]. A
  sibling leak introduced in [2] was recently fixed in [3]. As with [3]
  we should be using the wt_status_state_free_buffers() API introduced
  in [4].

- builtin/repack.c: Fix a leak that's been here since this use of
  "strbuf_release()" was added in a1bbc6c017 (repack: rewrite the shell
  script in C, 2013-09-15). We don't use the variable for anything
  except this loop, so we can instead free it right afterwards.

- builtin/rev-parse: Fix a leak that's been here since this code was
  added in 21d4783538 (Add a parseopt mode to git-rev-parse to bring
  parse-options to shell scripts., 2007-11-04).

- builtin/stash.c: Fix a couple of leaks that have been here since
  this code was added in d4788af875 (stash: convert create to builtin,
  2019-02-25), we strbuf_release()'d only some of the "struct strbuf" we
  allocated earlier in the function, let's release all of them.

- ref-filter.c: Fix a leak in 482c119186 (gpg-interface: improve
  interface for parsing tags, 2021-02-11), we don't use the "payload"
  variable that we ask parse_signature() to populate for us, so let's
  free it.

- t/helper/test-fake-ssh.c: Fix a leak that's been here since this
  code was added in 3064d5a38c (mingw: fix t5601-clone.sh,
  2016-01-27). Let's free the "struct strbuf" as soon as we don't need
  it anymore.

1. c45f0f525d (switch: reject if some operation is in progress,
   2019-03-29)
2. 2708ce62d2 (branch: sort detached HEAD based on a flag,
   2021-01-07)
3. abcac2e19f (ref-filter.c: fix a leak in get_head_description,
   2022-09-25)
4. 962dd7ebc3 (wt-status: introduce wt_status_state_free_buffers(),
   2020-09-27).

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-21 12:32:48 +09:00
Ævar Arnfjörð Bjarmason
083fd1a264 dir.c: free "ident" and "exclude_per_dir" in "struct untracked_cache"
When the "ident" member of the structure was added in
1e8fef609e (untracked cache: guard and disable on system changes,
2015-03-08) this function wasn't updated to free it. Let's do so.

Let's also free the "exclude_per_dir" memory we've been leaking
since[1], while making sure not to free() the constant ".gitignore"
string we add by default[2].

As we now have three struct members we're freeing let's change
free_untracked_cache() to return early if "uc" isn't defined. We won't
hand it to free() now, but that was just for convenience, once we're
dealing with >=2 struct members this pattern is more convenient.

1. f9e6c64958 (untracked cache: load from UNTR index extension,
   2015-03-08)
2. 039bc64e88 (core.excludesfile clean-up, 2007-11-14)

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-21 12:32:48 +09:00
Ævar Arnfjörð Bjarmason
b5fcb1c006 read-cache.c: clear and free "sparse_checkout_patterns"
The "sparse_checkout_patterns" member was added to the "struct
index_state" in 836e25c51b (sparse-checkout: hold pattern list in
index, 2021-03-30), but wasn't added to discard_index(). Let's do
that.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-21 12:32:48 +09:00
Ævar Arnfjörð Bjarmason
03267e8656 commit: discard partial cache before (re-)reading it
The read_cache() in prepare_to_commit() would end up clobbering the
pointer we had for a previously populated "the_index.cache_tree" in
the very common case of "git commit" stressed by e.g. the tests being
changed here.

We'd populate "the_index.cache_tree" by calling
"update_main_cache_tree" in prepare_index(), but would not end up with
a "fully prepared" index. What constitutes an existing index is
clearly overly fuzzy, here we'll check "active_nr" (aka
"the_index.cache_nr"), but our "the_index.cache_tree" might have been
malloc()'d already.

Thus the code added in 11c8a74a64 (commit: write cache-tree data when
writing index anyway, 2011-12-06) would end up allocating the
"cache_tree", and would interact here with code added in
7168624c35 (Do not generate full commit log message if it is not
going to be used, 2007-11-28). The result was a very common memory
leak.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-21 12:32:48 +09:00
Ævar Arnfjörð Bjarmason
ab2cf37183 {reset,merge}: call discard_index() before returning
These two built-ins both deal with the index, but weren't discarding
it. In subsequent commits we'll add more free()-ing to discard_index()
that we've missed, but let's first call the existing function.

We can doubtless add discard_index() (or its alias discard_cache()) to
a lot more places, but let's just add it here for now.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-21 12:32:48 +09:00
Ævar Arnfjörð Bjarmason
e5e37517dd tests: mark tests as passing with SANITIZE=leak
This marks tests that have been leak-free since various recent
commits, but which were not marked us such when the memory leak was
fixed. These were mostly discovered with the "check" mode added in
faececa53f (test-lib: have the "check" mode for SANITIZE=leak
consider leak logs, 2022-07-28).

Commits that fixed the last memory leak in these tests. Per narrowing
down when they started to pass under SANITIZE=leak with "bisect":

- t1022-read-tree-partial-clone.sh:
  7e2619d8ff (list_objects_filter_options: plug leak of filter_spec
  strings, 2022-09-08)

- t4053-diff-no-index.sh: 07a6f94a6d (diff-no-index: release prefixed
  filenames, 2022-09-07)

- t6415-merge-dir-to-symlink.sh: bac92b1f39 (Merge branch
  'js/ort-clean-up-after-failed-merge', 2022-08-08).

- t5554-noop-fetch-negotiator.sh:
  66eede4a37 (prepare_repo_settings(): plug leak of config values,
  2022-09-08)

- t2012-checkout-last.sh, t7504-commit-msg-hook.sh,
  t91{15,46,60}-git-svn-*.sh: The in-flight "pw/rebase-no-reflog-action"
  series, upon which this is based:
  https://lore.kernel.org/git/pull.1405.git.1667575142.gitgitgadget@gmail.com/

Let's mark all of these as passing with
"TEST_PASSES_SANITIZE_LEAK=true", to have it regression tested,
including as part of the "linux-leaks" CI job.

Additionally, let's remove the "!SANITIZE_LEAK" prerequisite from
tests that now pass, these were marked as failing in:

- 77e56d55ba (diff.c: fix a double-free regression in a18d66cefb,
  2022-03-17)
- c4d1d52631 (tests: change some 'test $(git) = "x"' to test_cmp,
  2022-03-07)

These were not spotted with the new "check" mode, but manually, it
doesn't cover these sort of prerequisites. There's few enough that we
shouldn't bother to automate it. They'll be going away sooner than
later.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-21 12:32:48 +09:00
Junio C Hamano
cb34852270 Merge branch 'pw/rebase-no-reflog-action' into ab/various-leak-fixes
* pw/rebase-no-reflog-action:
  rebase: stop exporting GIT_REFLOG_ACTION
  sequencer: stop exporting GIT_REFLOG_ACTION
2022-11-21 12:32:24 +09:00
Ævar Arnfjörð Bjarmason
07047d6829 cocci: apply "pending" index-compatibility to some "builtin/*.c"
Apply "index-compatibility.pending.cocci" rule to "builtin/*", but
exclude those where we conflict with in-flight changes.

As a result some of them end up using only "the_index", so let's have
them use the more narrow "USE_THE_INDEX_VARIABLE" rather than
"USE_THE_INDEX_COMPATIBILITY_MACROS".

Manual changes not made by coccinelle, that were squashed in:

* Whitespace-wrap argument lists for repo_hold_locked_index(),
  repo_read_index_preload() and repo_refresh_and_write_index(), in cases
  where the line became too long after the transformation.
* Change "refresh_cache()" to "refresh_index()" in a comment in
  "builtin/update-index.c".
* For those whose call was followed by perror("<macro-name>"), change
  it to perror("<function-name>"), referring to the new function.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-11-21 12:06:15 +09:00
Ævar Arnfjörð Bjarmason
bdafeae0b9 cache.h & test-tool.h: add & use "USE_THE_INDEX_VARIABLE"
In a preceding commit we fully applied the
"index-compatibility.pending.cocci" rule to "t/helper/*".

Let's now stop defining "USE_THE_INDEX_COMPATIBILITY_MACROS" in
test-tool.h itself, and instead instead define
"USE_THE_INDEX_VARIABLE" in the individual test helpers that need
it. This mirrors how we do the same thing in the "builtin/" directory.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-11-21 12:06:15 +09:00
Ævar Arnfjörð Bjarmason
666f53eb43 {builtin/*,repository}.c: add & use "USE_THE_INDEX_VARIABLE"
Split up the "USE_THE_INDEX_COMPATIBILITY_MACROS" into that setting
and a more narrow "USE_THE_INDEX_VARIABLE". In the case of these
built-ins we only need "the_index" variable, but not the compatibility
wrapper for functions we're not using.

Let's then have some users of "USE_THE_INDEX_COMPATIBILITY_MACROS" use
this more narrow and descriptive define.

For context: The USE_THE_INDEX_COMPATIBILITY_MACROS macro was added to
test-tool.h in f8adbec9fe (cache.h: flip
NO_THE_INDEX_COMPATIBILITY_MACROS switch, 2019-01-24).

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-11-21 12:06:15 +09:00
Ævar Arnfjörð Bjarmason
0ea414a14d cocci: apply "pending" index-compatibility to "t/helper/*.c"
Apply the "index-compatibility.pending.cocci" rule to the "t/helper/*"
directory, a subsequent commit will extend cache.h to further narrow
down the use of "USE_THE_INDEX_COMPATIBILITY_MACROS" in this area.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-11-21 12:06:15 +09:00
Ævar Arnfjörð Bjarmason
dc594180d9 cocci & cache.h: apply variable section of "pending" index-compatibility
Mostly apply the part of "index-compatibility.pending.cocci" that
renames the global variables like "active_nr", which are a shorthand
to referencing (in that case) a struct member as "the_index.cache_nr".

In doing so move more of "index-compatibility.pending.cocci" to
"index-compatibility.cocci".

In the case of "active_nr" we'd have a textual conflict with
"ab/various-leak-fixes" in "next"[1]. Let's exclude that specific case
while moving the rule over from "pending".

1. 407b94280f8 (commit: discard partial cache before (re-)reading it,
   2022-11-08)

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-11-21 12:06:15 +09:00
Ævar Arnfjörð Bjarmason
031b2033e0 cocci & cache.h: apply a selection of "pending" index-compatibility
Apply a selection of rules in "index-compatibility.pending.cocci"
tree-wide, and in doing so migrate them to
"index-compatibility.cocci".

As in preceding commits the only manual changes here are the macro
removals in "cache.h", and the update to the '*.cocci" rules. The rest
of the C code changes are the result of applying those updated rules.

Move rules for some rarely used cache compatibility macros from
"index-compatibility.pending.cocci" to "index-compatibility.cocci" and
apply them.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-11-21 12:06:15 +09:00
Ævar Arnfjörð Bjarmason
0e6550a2c6 cocci: add a index-compatibility.pending.cocci
Add a coccinelle rule which covers the rest of the macros guarded by
"USE_THE_INDEX_COMPATIBILITY_MACROS" cache.h. If the result of this
were applied it can be reduced down to just:

	#ifdef USE_THE_INDEX_COMPATIBILITY_MACROS
	extern struct index_state the_index;
	#endif

But that patch is just under 2000 lines, so let's first add this as a
"pending", and then incrementally pick changes from it in subsequent
commits. In doing that we'll migrate rules from this
"index-compatibility.pending.cocci" to the "index-compatibility.cocci"
created in a preceding commit.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-11-21 12:06:15 +09:00
Ævar Arnfjörð Bjarmason
9c5f3ee3b3 read-cache API & users: make discard_index() return void
The discard_index() function has not returned non-zero since
7a51ed66f6 (Make on-disk index representation separate from in-core
one, 2008-01-14), but we've had various code in-tree still acting as
though that might be the case.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-11-21 12:06:15 +09:00
Ævar Arnfjörð Bjarmason
fbc1ed629e cocci & cache.h: remove rarely used "the_index" compat macros
Since 4aab5b46f4 (Make read-cache.c "the_index" free., 2007-04-01)
we've been undergoing a slow migration away from these macros, but
haven't made much progress since f8adbec9fe (cache.h: flip
NO_THE_INDEX_COMPATIBILITY_MACROS switch, 2019-01-24).

Let's move forward a bit by changing the users of those macros that
are rare enough that we can convert them in one go, and then remove
the compatibility shim.

The only manual change to the C code here is to "cache.h", the rest is
all the result of applying the new "index-compatibility.cocci".

Even though it's a one-off, let's keep the coccinelle rules for
now. We'll extend them in subsequent commits, and this will help
anything that's in-flight or out-of-tree to migrate.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-11-21 12:06:15 +09:00
Ævar Arnfjörð Bjarmason
8f56511945 builtin/{grep,log}.: don't define "USE_THE_INDEX_COMPATIBILITY_MACROS"
Adding "USE_THE_INDEX_COMPATIBILITY_MACROS" to these two appears to
have been unnecessary from the start, as going back and compiling
f8adbec9fe (cache.h: flip NO_THE_INDEX_COMPATIBILITY_MACROS switch,
2019-01-24) without that addition works.

Let's not have these ask for the compatibility macros from cache.h
that they don't need.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-11-21 12:06:14 +09:00
Ævar Arnfjörð Bjarmason
c74e7b10b6 cache.h: remove unused "the_index" compat macros
The "active_alloc" macro added in 228e94f935 (Move index-related
variables into a structure., 2007-04-01) has not been used since
4aab5b46f4 (Make read-cache.c "the_index" free., 2007-04-01). Let's
remove it.

The rest of these are likewise unused, so let's not keep them
around. E.g. 12cd0bf9b0 (dir: stop using the index compatibility
macros, 2017-05-05) is the last use of "cache_dir_exists".

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-11-21 12:06:14 +09:00
Taylor Blau
a0789512c5 The thirteenth batch
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-18 18:48:53 -05:00
Taylor Blau
e87a229d57 Merge branch 'en/sparse-checkout-design'
Design doc.

* en/sparse-checkout-design:
  sparse-checkout.txt: new document with sparse-checkout directions
2022-11-18 18:44:01 -05:00
Taylor Blau
26734da056 Merge branch 'jk/branch-delete-detached'
Fix a bug where `git branch -d` did not work on an orphaned HEAD.

* jk/branch-delete-detached:
  branch: gracefully handle '-d' on orphan HEAD
2022-11-18 18:44:00 -05:00
Taylor Blau
35a62bb579 Merge branch 'mh/credential-unrecognized-attrs'
Docfix.

* mh/credential-unrecognized-attrs:
  docs: clarify that credential discards unrecognised attributes
2022-11-18 18:43:59 -05:00
Taylor Blau
a92fce4c50 Merge branch 'vd/skip-cache-tree-update'
Avoid calling 'cache_tree_update()' when doing so would be redundant.

* vd/skip-cache-tree-update:
  rebase: use 'skip_cache_tree_update' option
  read-tree: use 'skip_cache_tree_update' option
  reset: use 'skip_cache_tree_update' option
  unpack-trees: add 'skip_cache_tree_update' option
  cache-tree: add perf test comparing update and prime
2022-11-18 18:43:56 -05:00
Taylor Blau
3f98d7ab1b Merge branch 'mh/increase-credential-cache-timeout'
Update the credential-cache documentation to provide a more realistic
example.

* mh/increase-credential-cache-timeout:
  Documentation: increase example cache timeout to 1 hour
2022-11-18 18:43:55 -05:00
Taylor Blau
35dc2cf03f Merge branch 'vd/update-refs-delete'
`git rebase --update-refs` would delete references when all `update-ref`
commands in the sequencer were removed, which has been corrected.

* vd/update-refs-delete:
  rebase --update-refs: avoid unintended ref deletion
2022-11-18 18:43:11 -05:00
Taylor Blau
ad9096881d Merge branch 'tb/repack-expire-to'
"git repack" learns to send cruft objects out of the way into
packfiles outside the repository.

* tb/repack-expire-to:
  builtin/repack.c: implement `--expire-to` for storing pruned objects
  builtin/repack.c: write cruft packs to arbitrary locations
  builtin/repack.c: pass "cruft_expiration" to `write_cruft_pack`
  builtin/repack.c: pass "out" to `prepare_pack_objects`
2022-11-18 18:43:09 -05:00
Taylor Blau
e53598a5ab Merge branch 'ab/sha-makefile-doc'
Makefile comments updates and reordering to clarify knobs used to
choose SHA implementations.

* ab/sha-makefile-doc:
  Makefile: discuss SHAttered in *_SHA{1,256} discussion
  Makefile: document default SHA-1 backend on OSX
  Makefile & test-tool: replace "DC_SHA1" variable with a "define"
  Makefile: document SHA-1 and SHA-256 default and selection order
  Makefile: document default SHA-256 backend
  Makefile: rephrase the discussion of *_SHA1 knobs
  Makefile: create and use sections for "define" flag listing
  Makefile: correct DC_SHA1 documentation
  INSTALL: remove discussion of SHA-1 backends
  Makefile: always (re)set DC_SHA1 on fallback
2022-11-18 18:43:07 -05:00
Taylor Blau
69c1d609ba Merge branch 'ab/misc-hook-submodule-run-command'
Various test updates.

* ab/misc-hook-submodule-run-command:
  run-command tests: test stdout of run_command_parallel()
  submodule tests: reset "trace.out" between "grep" invocations
  hook tests: fix redirection logic error in 96e7225b31
2022-11-18 18:43:04 -05:00
Eric Wong
7025f54c40 delta-islands: free island-related data after use
On my use case involving 771 islands of Linux on kernel.org,
this reduces memory usage by around 25MB.  The bulk of that
comes from free_remote_islands, since free_config_regexes only
saves around 40k.

This memory is saved early in the memory-intensive pack process,
making it available for the remainder of the long process.

Signed-off-by: Eric Wong <e@80x24.org>
Co-authored-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-18 18:30:49 -05:00
Jeff King
8db2dad7a0 parse_object(): check on-disk type of suspected blob
In parse_object(), we try to handle blobs by streaming rather than
loading them entirely into memory. The most common case here will be
that we haven't seen the object yet and check oid_object_info(), which
tells us we have a blob.

But we trigger this code on one other case: when we have an in-memory
object struct with type OBJ_BLOB (and without its "parsed" flag set,
since otherwise we'd return early from the function). This indicates
that some other part of the code suspected we have a blob (e.g., it was
mentioned by a tree or tag) but we haven't yet looked at the on-disk
copy.

In this case before hitting the streaming path, we check if we have the
object on-disk at all. This is mostly pointless extra work, as the
streaming path would complain if it couldn't open the object (albeit
with the message "hash mismatch", which is a little misleading).

But it's also insufficient to catch all problems. The streaming code
will only tell us "yes, the on-disk object matches the oid". But it
doesn't actually confirm that what we found was indeed a blob, and
neither does repo_has_object_file().

One way to improve this would be to teach stream_object_signature() to
check the type (either by returning it to us to check, or taking an
"expected" type). But there's an even simpler fix here: if we suspect
the object is a blob, just call oid_object_info() to confirm that we
have it on-disk, and that it really is a blob.

This is slightly less efficient than teaching stream_object_signature()
to do it (since it has to open the object already). But this case very
rarely comes up. In practice, we usually don't have any clue what the
type is, in which case we already call oid_object_info(). This
"suspected" case happens only when some other code created an object
struct but didn't actually parse the blob, which is actually tricky to
trigger at all (see the discussion of the test below).

I reworked the conditional a bit so that instead of:

  if ((suspected_blob && oid_object_info() == OBJ_BLOB)
      (no_clue && oid_object_info() == OBJ_BLOB)

we have the simpler:

  if ((suspected_blob || no_clue) && oid_object_info() == OBJ_BLOB)

This is shorter, but also reflects what we really want say, which is
"have we ruled out this being a blob; if not, check it on-disk".

In either case, if oid_object_info() fails to tell us it's a blob, we'll
skip the streaming code path and call repo_read_object_file(), just as
before. And if we really do have a mismatch with the existing object
struct, we'll eventually call lookup_commit(), etc, via
parse_object_buffer(), which will complain that it doesn't match our
existing obj->type.

So this fixes one of the lingering expect_failure cases from 0616617c7e
(t: introduce tests for unexpected object types, 2019-04-09).  That test
works by peeling a tag that claims to point to a blob (triggering us to
create the struct), but really points to something else, which we later
discover when we call parse_object() as part of the actual traversal).
Prior to this commit, we'd quietly check the sha1 and mark the blob as
"parsed". Now we correctly complain about the mismatch.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-18 13:59:31 -05:00
Jeff King
04fb96219a parse_object(): drop extra "has" check before checking object type
When parsing an object of unknown type, we check to see if it's a blob,
so we can use our streaming code path. This uses oid_object_info() to
check the type, but before doing so we call repo_has_object_file(). This
latter is pointless, as oid_object_info() will already fail if the
object is missing. Checking it ahead of time just complicates the code
and is a waste of resources (albeit small).

Let's drop the redundant check.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-18 13:59:31 -05:00
Rubén Justo
cfbd173ccb branch: force-copy a branch to itself via @{-1} is a no-op
Since 52d59cc645 (branch: add a --copy (-c) option to go with --move
(-m), 2017-06-18) we can copy a branch to make a new branch with the
'-c' (copy) option or to overwrite an existing branch using the '-C'
(force copy) option.  A no-op possibility is considered when we are
asked to copy a branch to itself, to follow the same no-op introduced
for the rename (-M) operation in 3f59481e33 (branch: allow a no-op
"branch -M <current-branch> HEAD", 2011-11-25).  To check for this, in
52d59cc645 we compared the branch names provided by the user, source
(HEAD if omitted) and destination, and a match is considered as this
no-op.

Since ae5a6c3684 (checkout: implement "@{-N}" shortcut name for N-th
last branch, 2009-01-17) a branch can be specified using shortcuts like
@{-1}.  This allows this usage:

	$ git checkout -b test
	$ git checkout -
	$ git branch -C test test  # no-op
	$ git branch -C test @{-1} # oops
	$ git branch -C @{-1} test # oops

As we are using the branch name provided by the user to do the
comparison, if one of the branches is provided using a shortcut we are
not going to have a match and a call to git_config_copy_section() will
happen.  This will make a duplicate of the configuration for that
branch, and with this progression the second call will produce four
copies of the configuration, and so on.

Let's use the interpreted branch name instead for this comparison.

The rename operation is not affected.

Signed-off-by: Rubén Justo <rjusto@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-17 17:16:21 -05:00
Patrick Steinhardt
bcec6780b2 receive-pack: only use visible refs for connectivity check
When serving a push, git-receive-pack(1) needs to verify that the
packfile sent by the client contains all objects that are required by
the updated references. This connectivity check works by marking all
preexisting references as uninteresting and using the new reference tips
as starting point for a graph walk.

Marking all preexisting references as uninteresting can be a problem
when it comes to performance. Git forges tend to do internal bookkeeping
to keep alive sets of objects for internal use or make them easy to find
via certain references. These references are typically hidden away from
the user so that they are neither advertised nor writeable. At GitLab,
we have one particular repository that contains a total of 7 million
references, of which 6.8 million are indeed internal references. With
the current connectivity check we are forced to load all these
references in order to mark them as uninteresting, and this alone takes
around 15 seconds to compute.

We can optimize this by only taking into account the set of visible refs
when marking objects as uninteresting. This means that we may now walk
more objects until we hit any object that is marked as uninteresting.
But it is rather unlikely that clients send objects that make large
parts of objects reachable that have previously only ever been hidden,
whereas the common case is to push incremental changes that build on top
of the visible object graph.

This provides a huge boost to performance in the mentioned repository,
where the vast majority of its refs hidden. Pushing a new commit into
this repo with `transfer.hideRefs` set up to hide 6.8 million of 7 refs
as it is configured in Gitaly leads to a 4.5-fold speedup:

    Benchmark 1: main
      Time (mean ± σ):     30.977 s ±  0.157 s    [User: 30.226 s, System: 1.083 s]
      Range (min … max):   30.796 s … 31.071 s    3 runs

    Benchmark 2: pks-connectivity-check-hide-refs
      Time (mean ± σ):      6.799 s ±  0.063 s    [User: 6.803 s, System: 0.354 s]
      Range (min … max):    6.729 s …  6.850 s    3 runs

    Summary
      'pks-connectivity-check-hide-refs' ran
        4.56 ± 0.05 times faster than 'main'

As we mostly go through the same codepaths even in the case where there
are no hidden refs at all compared to the code before there is no change
in performance when no refs are hidden:

    Benchmark 1: main
      Time (mean ± σ):     48.188 s ±  0.432 s    [User: 49.326 s, System: 5.009 s]
      Range (min … max):   47.706 s … 48.539 s    3 runs

    Benchmark 2: pks-connectivity-check-hide-refs
      Time (mean ± σ):     48.027 s ±  0.500 s    [User: 48.934 s, System: 5.025 s]
      Range (min … max):   47.504 s … 48.500 s    3 runs

    Summary
      'pks-connectivity-check-hide-refs' ran
        1.00 ± 0.01 times faster than 'main'

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-17 16:22:52 -05:00
Patrick Steinhardt
5ff36c9b6b rev-parse: add --exclude-hidden= option
Add a new `--exclude-hidden=` option that is similar to the one we just
added to git-rev-list(1). Given a section name `uploadpack` or `receive`
as argument, it causes us to exclude all references that would be hidden
by the respective `$section.hideRefs` configuration.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-17 16:22:52 -05:00
Patrick Steinhardt
8c1bc2a71a revision: add new parameter to exclude hidden refs
Users can optionally hide refs from remote users in git-upload-pack(1),
git-receive-pack(1) and others via the `transfer.hideRefs`, but there is
not an easy way to obtain the list of all visible or hidden refs right
now. We'll require just that though for a performance improvement in our
connectivity check.

Add a new option `--exclude-hidden=` that excludes any hidden refs from
the next pseudo-ref like `--all` or `--branches`.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-17 16:22:52 -05:00
Patrick Steinhardt
1e9f273ac0 revision: introduce struct to handle exclusions
The functions that handle exclusion of refs work on a single string
list. We're about to add a second mechanism for excluding refs though,
and it makes sense to reuse much of the same architecture for both kinds
of exclusion.

Introduce a new `struct ref_exclusions` that encapsulates all the logic
related to excluding refs and move the `struct string_list` that holds
all wildmatch patterns of excluded refs into it. Rename functions that
operate on this struct to match its name.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-17 16:22:52 -05:00
Patrick Steinhardt
05b9425960 revision: move together exclusion-related functions
Move together the definitions of functions that handle exclusions of
refs so that related functionality sits in a single place, only.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-17 16:22:51 -05:00
Patrick Steinhardt
9b67eb6fbe refs: get rid of global list of hidden refs
We're about to add a new argument to git-rev-list(1) that allows it to
add all references that are visible when taking `transfer.hideRefs` et
al into account. This will require us to potentially parse multiple sets
of hidden refs, which is not easily possible right now as there is only
a single, global instance of the list of parsed hidden refs.

Refactor `parse_hide_refs_config()` and `ref_is_hidden()` so that both
take the list of hidden references as input and adjust callers to keep a
local list, instead. This allows us to easily use multiple hidden-ref
lists. Furthermore, it allows us to properly free this list before we
exit.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-17 16:22:51 -05:00
Patrick Steinhardt
5eeb9aa208 refs: fix memory leak when parsing hideRefs config
When parsing the hideRefs configuration, we first duplicate the config
value so that we can modify it. We then subsequently append it to the
`hide_refs` string list, which is initialized with `strdup_strings`
enabled. As a consequence we again reallocate the string, but never
free the first duplicate and thus have a memory leak.

While we never clean up the static `hide_refs` variable anyway, this is
no excuse to make the leak worse by leaking every value twice. We are
also about to change the way this variable will be handled so that we do
indeed start to clean it up. So let's fix the memory leak by using the
`string_list_append_nodup()` so that we pass ownership of the allocated
string to `hide_refs`.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-17 16:22:51 -05:00
Michael J Gruber
3c9b01f0bf notes: avoid empty line in template
When `git notes` prepares the template it adds an empty newline between
the comment header and the content:

>
> #
> # Write/edit the notes for the following object:
>
> # commit 0f3c55d4c2b7864bffb2d92278eff08d0b2e083f
> # etc

This is wrong structurally because that newline is part of the comment,
too, and thus should be commented. Also, it throws off some positioning
strategies of editors and plugins, and it differs from how we do commit
templates.

Change this to follow the standard set by `git commit`:

>
> #
> # Write/edit the notes for the following object:
> #
> # commit 0f3c55d4c2b7864bffb2d92278eff08d0b2e083f
>

Tests pass unchanged after this code change.

Signed-off-by: Michael J Gruber <git@grubix.eu>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-16 14:57:32 -05:00
Ævar Arnfjörð Bjarmason
23fb328c8d t7610: use "file:///dev/null", not "/dev/null", fixes MinGW
On MinGW the "/dev/null" is translated to "nul" on command-lines, even
though as in this case it'll never end up referring to an actual file.

So on Windows the fix for the previous "example.com" timeout issue in
8354cf752e (t7610: fix flaky timeout issue, don't clone from
example.com, 2022-11-05) would yield:

  fatal: repo URL: 'nul' must be absolute or begin with ./|../

Let's evade this yet again by prefixing this with "file://", which
makes this pass in the Windows CI.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-15 20:05:02 -05:00
Ævar Arnfjörð Bjarmason
049141dce9 bisect; remove unused "git-bisect.sh" and ".gitignore" entry
Since 73fce29427 (Turn `git bisect` into a full built-in, 2022-11-10)
we've used builtin/bisect.c instead of git-bisect.sh to implement the
"bisect" command.

Let's remove the unused leftover script, and the ".gitignore" entry for
the "git-bisect--helper", which also hasn't been built since
73fce29427.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-15 14:38:16 -05:00
Taylor Blau
03744bbdc4 builtin/gc.c: fix use-after-free in maintenance_unregister()
While trying to fix a move based on an uninitialized value (along with a
declaration after the first statement), be0fd57228
(maintenance --unregister: fix uninit'd data use &
-Wdeclaration-after-statement, 2022-11-15) unintentionally introduced a
use-after-free.

The problem arises when `maintenance_unregister()` sees a non-NULL
`config_file` string and thus tries to call
git_configset_get_value_multi() to lookup the corresponding values.

We store the result off, and then call git_configset_clear(), which
frees the pointer that we just stored. We then try to read that
now-freed pointer a few lines below, and there we have our
use-after-free:

    $ ./t7900-maintenance.sh -vxi --run=23 --valgrind
    [...]
    + git maintenance unregister --config-file ./other
    ==3048727== Invalid read of size 8
    ==3048727==    at 0x1869CA: maintenance_unregister (gc.c:1590)
    ==3048727==    by 0x188F42: cmd_maintenance (gc.c:2651)
    ==3048727==    by 0x128C62: run_builtin (git.c:466)
    ==3048727==    by 0x12907E: handle_builtin (git.c:721)
    ==3048727==    by 0x1292EC: run_argv (git.c:788)
    ==3048727==    by 0x12988E: cmd_main (git.c:926)
    ==3048727==    by 0x21ED39: main (common-main.c:57)
    ==3048727==  Address 0x4b38bc8 is 24 bytes inside a block of size 64 free'd
    ==3048727==    at 0x484617B: free (vg_replace_malloc.c:872)
    ==3048727==    by 0x2D207E: free_individual_entries (hashmap.c:188)
    ==3048727==    by 0x2D2153: hashmap_clear_ (hashmap.c:207)
    ==3048727==    by 0x270B5C: git_configset_clear (config.c:2375)
    ==3048727==    by 0x1869AC: maintenance_unregister (gc.c:1585)
    ==3048727==    by 0x188F42: cmd_maintenance (gc.c:2651)
    ==3048727==    by 0x128C62: run_builtin (git.c:466)
    ==3048727==    by 0x12907E: handle_builtin (git.c:721)
    ==3048727==    by 0x1292EC: run_argv (git.c:788)
    ==3048727==    by 0x12988E: cmd_main (git.c:926)
    ==3048727==    by 0x21ED39: main (common-main.c:57)
    [...]

Resolve this via a partial-revert of be0fd57228. The config_set struct
now gets a zero initialization, which makes free()-ing it a noop even
without calling git_configset_init(). When we do initialize it to a
non-zero value, it is only free()'d after our last read of `list`.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-15 13:56:11 -05:00
Ævar Arnfjörð Bjarmason
be0fd57228 maintenance --unregister: fix uninit'd data use & -Wdeclaration-after-statement
Since (maintenance: add option to register in a specific config,
2022-11-09) we've been unable to build with "DEVELOPER=1" without
"DEVOPTS=no-error", as the added code triggers a
"-Wdeclaration-after-statement" warning.

And worse than that, the data handed to git_configset_clear() is
uninitialized, as can be spotted with e.g.:

	./t7900-maintenance.sh -vixd --run=23 --valgrind
	[...]
	+ git maintenance unregister --force
	Conditional jump or move depends on uninitialised value(s)
	   at 0x6B5F1E: git_configset_clear (config.c:2367)
	   by 0x4BA64E: maintenance_unregister (gc.c:1619)
	   by 0x4BD278: cmd_maintenance (gc.c:2650)
	   by 0x409905: run_builtin (git.c:466)
	   by 0x40A21C: handle_builtin (git.c:721)
	   by 0x40A58E: run_argv (git.c:788)
	   by 0x40AF68: cmd_main (git.c:926)
	   by 0x5D39FE: main (common-main.c:57)
	 Uninitialised value was created by a stack allocation
	   at 0x4BA22C: maintenance_unregister (gc.c:1557)

Let's fix both of these issues, and also move the scope of the
variable to the "if" statement it's used in, to make it obvious where
it's used.

Helped-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-15 12:31:53 -05:00
Ronan Pigott
1f80129d61 maintenance: add option to register in a specific config
maintenance register currently records the maintenance repo exclusively
within the user's global configuration, but other configuration files
may be relevant when running maintenance if they are included from the
global config. This option allows the user to choose where maintenance
repos are recorded.

Signed-off-by: Ronan Pigott <ronan@rjp.ie>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-14 22:39:25 -05:00
Ronan Pigott
13d5bbdf72 for-each-repo: interpolate repo path arguments
This is a quality of life change for git-maintenance, so repos can be
recorded with the tilde syntax. The register subcommand will not record
repos in this format by default.

Signed-off-by: Ronan Pigott <ronan@rjp.ie>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-14 22:39:25 -05:00
Taylor Blau
eea7033409 The twelfth batch
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-14 19:56:07 -05:00
Taylor Blau
3c5d0ce3f5 Merge branch 'vh/my-first-contribution-typo'
Documentation fix.

* vh/my-first-contribution-typo:
  Documentation: fix typo
2022-11-14 19:53:55 -05:00
Taylor Blau
859899ddc1 Merge branch 'ks/partialclone-casing'
Documentation fix.

* ks/partialclone-casing:
  repository-version.txt: partialClone casing change
2022-11-14 19:53:43 -05:00