Commit Graph

75150 Commits

Author SHA1 Message Date
Patrick Steinhardt
6ef9f77a15 builtin/commit: fix leaking cleanup config
The cleanup string set by the config is leaking when it is being
overridden by an option. Fix this by tracking these via two separate
variables such that we can free the old value.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-11-04 22:37:54 -08:00
Patrick Steinhardt
ff31b7b941 trailer: fix leaking strbufs when formatting trailers
When formatting trailer lines we iterate through each of the trailers
and munge their respective token/value pairs according to the trailer
options. When formatting a trailer that has its `item->token` pointer
set we perform the munging in two local buffers. In the case where we
figure out that the value is empty and `trim_empty` is set we just skip
over the trailer item. But the buffers are local to the loop and we
don't release their contents, leading to a memory leak.

Plug this leak by lifting the buffers outside of the loop and releasing
them on function return. This fixes the memory leaks, but also optimizes
the loop as we don't have to reallocate the buffers on every single
iteration.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-11-04 22:37:54 -08:00
Patrick Steinhardt
3f692fe5be trailer: fix leaking trailer values
Fix leaking trailer values when replacing the value with a command or
when the token value is empty.

This leak is exposed by t7513, but plugging it does not make the whole
test suite pass.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-11-04 22:37:54 -08:00
Patrick Steinhardt
d34b5cbf02 builtin/commit: fix leaking change data contents
While we free the worktree change data, we never free its contents. Fix
this.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-11-04 22:37:53 -08:00
Patrick Steinhardt
3b373150c8 upload-pack: fix leaking URI protocols
We don't clear `struct upload_pack::uri_protocols`, which causes a
memory leak. Fix this.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-11-04 22:37:53 -08:00
Patrick Steinhardt
0b20a28811 pretty: clear signature check
The signature check in the formatting context is never getting released.
Fix this to plug the resulting memory leak.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-11-04 22:37:53 -08:00
Patrick Steinhardt
8dd3cb4b45 diff-lib: fix leaking diffopts in do_diff_cache()
In `do_diff_cache()` we initialize a new `rev_info` and then overwrite
its `diffopt` with a user-provided set of options. This can leak memory
because `repo_init_revisions()` may end up allocating memory for the
`diffopt` itself depending on the configuration. And since that field is
overwritten we won't ever free it.

Plug the memory leak by releasing the diffopts before we overwrite them.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-11-04 22:37:52 -08:00
Patrick Steinhardt
e29ff075e0 revision: fix leaking bloom filters
The memory allocated by `prepare_to_use_bloom_filter()` is not released
by `release_revisions()`, causing a memory leak. Plug it.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-11-04 22:37:52 -08:00
Patrick Steinhardt
43fedde3df builtin/grep: fix leak with --max-count=0
When executing with `--max-count=0` we'll return early from git-grep(1)
without performing any cleanup, which causes memory leaks. Plug these.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-11-04 22:37:52 -08:00
Patrick Steinhardt
a6590ccdd4 grep: fix leak in grep_splice_or()
In `grep_splice_or()` we search for the next `TRUE` node in our tree of
grep expressions and replace it with the given new expression. But we
don't free the old node, which causes a memory leak. Plug it.

This leak is exposed by t7810, but plugging it alone isn't sufficient to
make the test suite pass.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-11-04 22:37:52 -08:00
Patrick Steinhardt
ee3e8c3afa t/helper: fix leaks in "reach" test tool
The "reach" test tool doesn't bother to clean up any of its allocated
resources, causing various leaks. Plug them.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-11-04 22:37:51 -08:00
Patrick Steinhardt
5f5dd8e297 builtin/ls-remote: plug leaking server options
The list of server options populated via `OPT_STRING_LIST()` is never
cleared, causing a memory leak. Plug it.

This leak is exposed by t5702, but plugging it alone does not make the
whole test suite pass.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-11-04 22:37:51 -08:00
Taylor Blau
34b6ce9b30 The third batch
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2024-10-18 14:01:50 -04:00
Taylor Blau
c1662a00b6 Merge branch 'ps/maintenance-start-crash-fix'
"git maintenance start" crashed due to an uninitialized variable
reference, which has been corrected.

* ps/maintenance-start-crash-fix:
  builtin/gc: fix crash when running `git maintenance start`
2024-10-18 13:56:26 -04:00
Taylor Blau
2849552beb Merge branch 'xx/protocol-v2-doc-markup-fix'
Docfix.

* xx/protocol-v2-doc-markup-fix:
  Documentation/gitprotocol-v2.txt: fix a slight inconsistency in format
2024-10-18 13:56:25 -04:00
Taylor Blau
728ae63c05 Merge branch 'tc/bundle-uri-leakfix'
Leakfix.

* tc/bundle-uri-leakfix:
  bundle-uri: plug leak in unbundle_from_file()
2024-10-18 13:56:24 -04:00
Taylor Blau
645cc7a2a7 Merge branch 'kh/checkout-ignore-other-docfix'
Doc updates.

* kh/checkout-ignore-other-docfix:
  checkout: refer to other-worktree branch, not ref
2024-10-18 13:56:24 -04:00
Taylor Blau
4491734107 Merge branch 'kh/merge-tree-doc'
Docfix.

* kh/merge-tree-doc:
  doc: merge-tree: improve example script
2024-10-18 13:56:23 -04:00
Taylor Blau
6fe1b8cee0 Merge branch 'ng/rebase-merges-branch-name-as-label'
"git rebase --rebase-merges" now uses branch names as labels when
able.

* ng/rebase-merges-branch-name-as-label:
  rebase-merges: try and use branch names as labels
  rebase-update-refs: extract load_branch_decorations
  load_branch_decorations: fix memory leak with non-static filters
2024-10-18 13:56:22 -04:00
Taylor Blau
b967851417 Merge branch 'kn/loose-object-layer-wo-global-hash'
Code clean-up.

* kn/loose-object-layer-wo-global-hash:
  loose: don't rely on repository global state
2024-10-18 13:56:22 -04:00
Taylor Blau
ee064ba65a Merge branch 'jc/doc-refspec-syntax'
Doc updates.

* jc/doc-refspec-syntax:
  doc: clarify <src> in refspec syntax
2024-10-18 13:56:20 -04:00
Taylor Blau
020c16bdb9 Merge branch 'aa/t7300-modernize'
Test modernization.

* aa/t7300-modernize:
  t7300-clean.sh: use test_path_* helper functions for error logging
2024-10-18 13:54:43 -04:00
Taylor Blau
15030f9556 The second batch
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2024-10-15 17:12:40 -04:00
Taylor Blau
b43e23fa02 Merge branch 'jk/fsmonitor-event-listener-race-fix'
On macOS, fsmonitor can fall into a race condition that results in
a client waiting forever to be notified for an event that have
already happened.  This problem has been corrected.

* jk/fsmonitor-event-listener-race-fix:
  fsmonitor: initialize fs event listener before accepting clients
  simple-ipc: split async server initialization and running
2024-10-15 16:56:43 -04:00
Taylor Blau
fd98f659fd Merge branch 'xx/remote-server-option-config'
A new configuration variable remote.<name>.serverOption makes the
transport layer act as if the --serverOption=<value> option is
given from the command line.

* xx/remote-server-option-config:
  ls-remote: leakfix for not clearing server_options
  fetch: respect --server-option when fetching multiple remotes
  transport.c:🤝 make use of server options from remote
  remote: introduce remote.<name>.serverOption configuration
  transport: introduce parse_transport_option() method
2024-10-15 16:56:43 -04:00
Taylor Blau
8a5545b949 Merge branch 'js/doc-platform-support-link-fix'
Docfix.

* js/doc-platform-support-link-fix:
  docs: fix the `maintain-git` links in `technical/platform-support`
2024-10-15 16:56:43 -04:00
Taylor Blau
f004467b04 Merge branch 'jh/config-unset-doc-fix'
Docfix.

* jh/config-unset-doc-fix:
  git-config.1: remove value from positional args in unset usage
2024-10-15 16:56:43 -04:00
Junio C Hamano
ef8ce8f3d4 Start the 2.48 cycle
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-10-10 14:22:30 -07:00
Junio C Hamano
3eb4cc451e Merge branch 'jk/output-prefix-cleanup'
Code clean-up.

* jk/output-prefix-cleanup:
  diff: store graph prefix buf in git_graph struct
  diff: return line_prefix directly when possible
  diff: return const char from output_prefix callback
  diff: drop line_prefix_length field
  line-log: use diff_line_prefix() instead of custom helper
2024-10-10 14:22:30 -07:00
Junio C Hamano
31bc4454de Merge branch 'ps/leakfixes-part-8'
More leakfixes.

* ps/leakfixes-part-8: (23 commits)
  builtin/send-pack: fix leaking list of push options
  remote: fix leaking push reports
  t/helper: fix leaks in proc-receive helper
  pack-write: fix return parameter of `write_rev_file_order()`
  revision: fix leaking saved parents
  revision: fix memory leaks when rewriting parents
  midx-write: fix leaking buffer
  pack-bitmap-write: fix leaking OID array
  pseudo-merge: fix leaking strmap keys
  pseudo-merge: fix various memory leaks
  line-log: fix several memory leaks
  diff: improve lifecycle management of diff queues
  builtin/revert: fix leaking `gpg_sign` and `strategy` config
  t/helper: fix leaking repository in partial-clone helper
  builtin/clone: fix leaking repo state when cloning with bundle URIs
  builtin/pack-redundant: fix various memory leaks
  builtin/stash: fix leaking `pathspec_from_file`
  submodule: fix leaking submodule entry list
  wt-status: fix leaking buffer with sparse directories
  shell: fix leaking strings
  ...
2024-10-10 14:22:29 -07:00
Junio C Hamano
d29d644d18 Merge branch 'ds/line-log-asan-fix'
Use after free and double freeing at the end in "git log -L... -p"
had been identified and fixed.

* ds/line-log-asan-fix:
  line-log: protect inner strbuf from free
2024-10-10 14:22:27 -07:00
Junio C Hamano
e29296745d Merge branch 'sk/doc-maintenance-schedule'
Doc update to clarify how periodical maintenance are scheduled,
spread across time to avoid thundering hurds.

* sk/doc-maintenance-schedule:
  doc: add a note about staggering of maintenance
2024-10-10 14:22:26 -07:00
Junio C Hamano
325772f0d5 Merge branch 'tb/notes-amlog-doc'
Document "amlog" notes.

* tb/notes-amlog-doc:
  Documentation: mention the amlog in howto/maintain-git.txt
2024-10-10 14:22:25 -07:00
Junio C Hamano
5575c713c2 Merge branch 'ps/reftable-alloc-failures'
The reftable library is now prepared to expect that the memory
allocation function given to it may fail to allocate and to deal
with such an error.

* ps/reftable-alloc-failures: (26 commits)
  reftable/basics: fix segfault when growing `names` array fails
  reftable/basics: ban standard allocator functions
  reftable: introduce `REFTABLE_FREE_AND_NULL()`
  reftable: fix calls to free(3P)
  reftable: handle trivial allocation failures
  reftable/tree: handle allocation failures
  reftable/pq: handle allocation failures when adding entries
  reftable/block: handle allocation failures
  reftable/blocksource: handle allocation failures
  reftable/iter: handle allocation failures when creating indexed table iter
  reftable/stack: handle allocation failures in auto compaction
  reftable/stack: handle allocation failures in `stack_compact_range()`
  reftable/stack: handle allocation failures in `reftable_new_stack()`
  reftable/stack: handle allocation failures on reload
  reftable/reader: handle allocation failures in `reader_init_iter()`
  reftable/reader: handle allocation failures for unindexed reader
  reftable/merged: handle allocation failures in `merged_table_init_iter()`
  reftable/writer: handle allocation failures in `reftable_new_writer()`
  reftable/writer: handle allocation failures in `writer_index_hash()`
  reftable/record: handle allocation failures when decoding records
  ...
2024-10-10 14:22:25 -07:00
Junio C Hamano
799450316b Merge branch 'ja/doc-synopsis-markup'
The way AsciiDoc is used for SYNOPSIS part of the manual pages has
been revamped.  The sources, at least for the simple cases, got
vastly pleasant to work with.

* ja/doc-synopsis-markup:
  doc: apply synopsis simplification on git-clone and git-init
  doc: update the guidelines to reflect the current formatting rules
  doc: introduce a synopsis typesetting
2024-10-10 14:22:24 -07:00
Kristoffer Haugsbakk
b8139c8f4e checkout: refer to other-worktree branch, not ref
We can only check out commits or branches, not refs in general.  And the
problem here is if another worktree is using the branch that we want to
check out.

Let’s be more direct and just talk about branches instead of refs.

Also replace “be held” with “in use”.  Further, “in use” is not
restricted to a branch being checked out (e.g. the branch could be busy
on a rebase), hence generalize to “or otherwise in use” in the option
description.

Signed-off-by: Kristoffer Haugsbakk <code@khaugsbakk.name>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-10-10 13:09:13 -07:00
Xing Xin
f1ed39987b Documentation/gitprotocol-v2.txt: fix a slight inconsistency in format
Signed-off-by: Xing Xin <xingxin.xx@bytedance.com>
Acked-by: Kristoffer Haugsbakk <kristofferhaugsbakk@fastmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-10-10 11:54:07 -07:00
Toon Claes
6dab49b9fb bundle-uri: plug leak in unbundle_from_file()
The function `unbundle_from_file()` has two memory leaks:

  - We do not release the `struct bundle_header header` when hitting
    errors because we return early without any cleanup.

  - We do not release the `struct strbuf bundle_ref` at all.

Plug these leaks by creating a common exit path where both of these
variables are released.

While at it, refactor the code such that the variable assignments do not
happen inside the conditional statement itself according to our coding
style.

Signed-off-by: Toon Claes <toon@iotcl.com>
Acked-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-10-10 11:47:24 -07:00
Patrick Steinhardt
c95547a394 builtin/gc: fix crash when running git maintenance start
It was reported on the mailing list that running `git maintenance start`
immediately segfaults starting with b6c3f8e12c (builtin/maintenance: fix
leak in `get_schedule_cmd()`, 2024-09-26). And indeed, this segfault is
trivial to reproduce up to a point where one is scratching their head
why we didn't catch this regression in our test suite.

The root cause of this error is `get_schedule_cmd()`, which does not
populate the `out` parameter in all cases anymore starting with the
mentioned commit. Callers do assume it to always be populated though and
will e.g. call `strvec_split()` on the returned value, which will of
course segfault when the variable is uninitialized.

So why didn't we catch this trivial regression? The reason is that our
tests always set up the "GIT_TEST_MAINT_SCHEDULER" environment variable
via "t/test-lib.sh", which allows us to override the scheduler command
with a custom one so that we don't accidentally modify the developer's
system. But the faulty code where we don't set the `out` parameter will
only get hit in case that environment variable is _not_ set, which is
never the case when executing our tests.

Fix the regression by again unconditionally allocating the value in the
`out` parameter, if provided. Add a test that unsets the environment
variable to catch future regressions in this area.

Reported-by: Shubham Kanodia <shubham.kanodia10@gmail.com>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-10-10 10:04:43 -07:00
Junio C Hamano
8ead1bba3e doc: clarify <src> in refspec syntax
We explicitly avoid saying "ref <src>" when introducing the source
side of a refspec, because it can be a fully-spelled hexadecimal
object name, and it also can be a pattern that is not quite a "ref".

But we are loose when we introduce <dst> and say "ref <dst>", even
though it can also be a pattern.  Let's omit "ref" also from the
destination side.

Clarify that <src> can be a ref, a (limited glob) pattern, or an
object name.

Even though the very original design of refspec expected that '*'
was used only at the end (e.g., "refs/heads/*" was expected, but not
"refs/heads/*-wip"), the code and its use evolved to handle a single
'*' anywhere in the pattern.  Update the text to remove the mention
of "the same prefix".  Anything that matches the pattern are named
by such a (limited glob) pattern in <src>.

Also put a bit more stress on the fact that we accept only one '*'
in the pattern by saying "one and only one `*`".

Helped-by: Monika Kairaitytė <monika@kibit.lt>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-10-09 16:59:01 -07:00
Abraham Samuel Adekunle
77af53f56f t7300-clean.sh: use test_path_* helper functions for error logging
This test script uses "test - [def]", but when a test fails because
the file passed to it does not exist,
it fails silently without an error message.
Use test_path_* helper functions, which are designed to give better
error messages when their expectations are not met.

I have added a mechanical validation that applies the same transformation
done in this patch, when the test script is passed to a sed script as shown
below.

sed -e 's/^\(	*\)test -f /\1test_path_is_file /' \
    -e 's/^\(	*\)test -d /\1test_path_is_dir /' \
    -e 's/^\(	*\)test -e /\1test_path_exists /' \
    -e 's/^\(	*\)! test -[edf] /\1test_path_is_missing /' \
    -e 's/^\(	*\)test ! -[edf] /\1test_path_is_missing /' \
       "$1" >foo.sh

Reviewers can use the sed script to tranform the original test script and
compare the result in foo.sh with the results of applying the patch.
You will see an instance of "!(test -e 3)" which was manually replaced with
""test_path_is_missing 3", and everything else should match.

Careful and deliberate observation was done to check instances where
"test ! - [df] foo" was used in the test script to make sure that the test
instances were expecting foo to EITHER be a file or a directory, and NOT a
possibility of being both as this would make replacing "test ! -f foo" with
"test_path_is_missing foo" unreasonable.

In the tests control flow, foo has been created as EITHER a
reguar file OR a directory and should NOT exist
after "git clean" or "git clean -d", as the case maybe, has been called.
This made it reasonable to replace
"test ! -[df] foo" with "test_path_is_missing foo".

Signed-off-by: Abraham Samuel Adekunle <abrahamadekunle50@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-10-09 15:04:39 -07:00
Karthik Nayak
432f666aa6 loose: don't rely on repository global state
In `loose.c`, we rely on the global variable `the_hash_algo`. As such we
have guarded the file with the 'USE_THE_REPOSITORY_VARIABLE' definition.
Let's derive the hash algorithm from the available repository variable
and remove this guard. This brings us one step closer to removing the
global 'the_repository' variable.

Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-10-09 11:51:31 -07:00
Nicolas Guichard
436892123d rebase-merges: try and use branch names as labels
When interactively rebasing merge commits, the commit message is parsed to
extract a probably meaningful label name. For instance if the merge commit
is “Merge branch 'feature0'”, then the rebase script will have thes lines:
```
label feature0

merge -C $sha feature0 # “Merge branch 'feature0'
```

This heuristic fails in the case of octopus merges or when the merge commit
message is actually unrelated to the parent commits.

An example that combines both is:
```
*---.   967bfa4 (HEAD -> integration) Integration
|\ \ \
| | | * 2135be1 (feature2, feat2) Feature 2
| |_|/
|/| |
| | * c88b01a Feature 1
| |/
|/|
| * 75f3139 (feat0) Feature 0
|/
* 25c86d0 (main) Initial commit
```
yields the labels Integration, Integration-2 and Integration-3.

Fix this by using a branch name for each merge commit's parent that is the
tip of at least one branch, and falling back to a label derived from the
merge commit message otherwise.
In the example above, the labels become feat0, Integration and feature2.

Signed-off-by: Nicolas Guichard <nicolas@guichard.eu>
Acked-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-10-09 10:52:46 -07:00
Nicolas Guichard
68c9fcb027 rebase-update-refs: extract load_branch_decorations
Extract load_branch_decorations from todo_list_add_update_ref_commands so
it can be re-used in make_script_with_merges.

Since it can now be called multiple times, use non-static lists and place
it next to load_ref_decorations to re-use the decoration_loaded guard.

Signed-off-by: Nicolas Guichard <nicolas@guichard.eu>
Acked-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-10-09 10:52:45 -07:00
Nicolas Guichard
e4d03b7938 load_branch_decorations: fix memory leak with non-static filters
load_branch_decorations calls normalize_glob_ref on each string of filter's
string_lists. This effectively replaces the potentially non-owning char* of
those items with an owning char*.

Set the strdup_string flag on those string_lists.

This was not caught until now because:
- when passing string_lists already with the strdup_string already set, the
  behaviour was correct
- when passing static string_lists, the new char* remain reachable until
  program exit

Signed-off-by: Nicolas Guichard <nicolas@guichard.eu>
Acked-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-10-09 10:52:44 -07:00
Kristoffer Haugsbakk
c4b8fb6ef2 doc: merge-tree: improve example script
• Provide a commit message in the example command.

  The command will hang since it is waiting for a commit message on
  stdin.  Which is usable but not straightforward enough since this is
  example code.
• Use `||` directly since that is more straightforward than checking the
  last exit status.

  Also use `echo` and `exit` since `die` is not defined.
• Expose variable declarations.

Signed-off-by: Kristoffer Haugsbakk <code@khaugsbakk.name>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-10-09 10:40:42 -07:00
Josh Heinrichs
f36b8cbaef git-config.1: remove value from positional args in unset usage
The synopsis for `git config unset` mentions two positional arguments:
`<name>` and `<value>`. While the first argument is correct, the second
is not. Users are expected to provide the value via `--value=<value>`.

Remove the positional argument. The `--value=<value>` option is already
documented correctly, so this is all we need to do to fix the
documentation.

Signed-off-by: Josh Heinrichs <joshiheinrichs@gmail.com>
Reviewed-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-10-08 23:35:45 -07:00
Jeff King
51907f8fee fsmonitor: initialize fs event listener before accepting clients
There's a racy hang in fsmonitor on macOS that we sometimes see in CI.
When we serve a client, what's supposed to happen is:

  1. The client thread calls with_lock__wait_for_cookie() in which we
     create a cookie file and then wait for a pthread_cond event

  2. The filesystem event listener sees the cookie file creation, does
     some internal book-keeping, and then triggers the pthread_cond.

But there's a problem: we start the listener that accepts client threads
before we start the fs event thread. So it's possible for us to accept a
client which creates the cookie file and starts waiting before the fs
event thread is initialized, and we miss those filesystem events
entirely. That leaves the client thread hanging forever.

In CI, the symptom is that t9210 (which is testing scalar, which always
enables fsmonitor under the hood) may hang forever in "scalar clone". It
is waiting on "git fetch" which is waiting on the fsmonitor daemon.

The race happens more frequently under load, but you can trigger it
predictably with a sleep like this, which delays the start of the fs
event thread:

  --- a/compat/fsmonitor/fsm-listen-darwin.c
  +++ b/compat/fsmonitor/fsm-listen-darwin.c
  @@ -510,6 +510,7 @@ void fsm_listen__loop(struct fsmonitor_daemon_state *state)
          FSEventStreamSetDispatchQueue(data->stream, data->dq);
          data->stream_scheduled = 1;

  +       sleep(1);
          if (!FSEventStreamStart(data->stream)) {
                  error(_("Failed to start the FSEventStream"));
                  goto force_error_stop_without_loop;

One solution might be to reverse the order of initialization: start the
fs event thread before we start the thread listening for clients. But
the fsmonitor code explicitly does it in the opposite direction. The fs
event thread wants to refer to the ipc_server_data struct, so we need it
to be initialized first.

A further complication is that we need a signal from the fs event thread
that it is actually ready and listening. And those details happen within
backend-specific fsmonitor code, whereas the initialization is in the
shared code.

So instead, let's use the ipc_server init/start split added in the
previous commit. The generic fsmonitor code will init the ipc_server but
_not_ start it, leaving that to the backend specific code, which now
needs to call ipc_server_start_async() at the right time.

For macOS, that is right after we start the FSEventStream that you can
see in the diff above.

It's not clear to me if Windows suffers from the same problem (and we
simply don't trigger it in CI), or if it is immune. Regardless, the
obvious place to start accepting clients there is right after we've
established the ReadDirectoryChanges watch.

This makes the hangs go away in our macOS CI environment, even when
compiled with the sleep() above.

Helped-by: Koji Nakamaru <koji.nakamaru@gree.net>
Signed-off-by: Jeff King <peff@peff.net>
Acked-by: Koji Nakamaru <koji.nakamaru@gree.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-10-08 12:03:56 -07:00
Jeff King
766fce69e9 simple-ipc: split async server initialization and running
To start an async ipc server, you call ipc_server_run_async(). That
initializes the ipc_server_data object, and starts all of the threads
running, which may immediately start serving clients.

This can create some awkward timing problems, though. In the fsmonitor
daemon (the sole user of the simple-ipc system), we want to create the
ipc server early in the process, which means we may start serving
clients before the rest of the daemon is fully initialized.

To solve this, let's break run_async() into two parts: an initialization
which allocates all data and spawns the threads (without letting them
run), and a start function which actually lets them begin work. Since we
have two simple-ipc implementations, we have to handle this twice:

  - in ipc-unix-socket.c, we have a central listener thread which hands
    connections off to worker threads using a work_available mutex. We
    can hold that mutex after init, and release it when we're ready to
    start.

    We do need an extra "started" flag so that we know whether the main
    thread is holding the mutex or not (e.g., if we prematurely stop the
    server, we want to make sure all of the worker threads are released
    to hear about the shutdown).

  - in ipc-win32.c, we don't have a central mutex. So we'll introduce a
    new startup_barrier mutex, which we'll similarly hold until we're
    ready to let the threads proceed.

    We again need a "started" flag here to make sure that we release the
    barrier mutex when shutting down, so that the sub-threads can
    proceed to the finish.

I've renamed the run_async() function to init_async() to make sure we
catch all callers, since they'll now need to call the matching
start_async().

We could leave run_async() as a wrapper that does both, but there's not
much point. There are only two callers, one of which is fsmonitor, which
will want to actually do work between the two calls. And the other is
just a test-tool wrapper.

For now I've added the start_async() calls in fsmonitor where they would
otherwise have happened, so there should be no behavior change with this
patch.

Signed-off-by: Jeff King <peff@peff.net>
Acked-by: Koji Nakamaru <koji.nakamaru@gree.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-10-08 12:03:56 -07:00
Xing Xin
0f490d270a ls-remote: leakfix for not clearing server_options
Ensure `server_options` is properly cleared using `string_list_clear()`
in `builtin/ls-remote.c:cmd_ls_remote`.

Although we cannot yet enable `TEST_PASSES_SANITIZE_LEAK=true` for
`t/t5702-protocol-v2.sh` due to other existing leaks, this fix ensures
that "git-ls-remote" related server options tests pass the sanitize leak
check:

  ...
  ok 12 - server-options are sent when using ls-remote
  ok 13 - server-options from configuration are used by ls-remote
  ...

Signed-off-by: Xing Xin <xingxin.xx@bytedance.com>
Reviewed-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-10-08 10:22:10 -07:00