First step of deprecating and removing merge-recursive.
* en/merge-ort-prepare-to-remove-recursive:
am: switch from merge_recursive_generic() to merge_ort_generic()
merge-ort: fix merge.directoryRenames=false
t3650: document bug when directory renames are turned off
merge-ort: support having merge verbosity be set to 0
merge-ort: allow rename detection to be disabled
merge-ort: add new merge_ort_generic() function
Junio C Hamano [Sat, 29 Mar 2025 07:39:06 +0000 (16:39 +0900)]
Merge branch 'cc/signed-fast-export-import'
"git fast-export | git fast-import" learns to deal with commit and
tag objects with embedded signatures a bit better.
* cc/signed-fast-export-import:
fast-export, fast-import: add support for signed-commits
fast-export: do not modify memory from get_commit_buffer
git-fast-export.adoc: clarify why 'verbatim' may not be a good idea
fast-export: rename --signed-tags='warn' to 'warn-verbatim'
fast-export: fix missing whitespace after switch
git-fast-import.adoc: add missing LF in the BNF
Junio C Hamano [Wed, 26 Mar 2025 07:26:10 +0000 (16:26 +0900)]
Merge branch 'en/merge-process-renames-crash-fix'
The merge-recursive and merge-ort machinery crashed in corner cases
when certain renames are involved.
* en/merge-process-renames-crash-fix:
merge-ort: fix slightly overzealous assertion for rename-to-self
t6423: add a testcase causing a failed assertion in process_renames
Junio C Hamano [Wed, 26 Mar 2025 07:26:10 +0000 (16:26 +0900)]
Merge branch 'ua/some-builtins-wo-the-repository'
A handful of built-in command implementations have been rewritten
to use the repository instance supplied by git.c:run_builtin(), its
caller.
* ua/some-builtins-wo-the-repository:
builtin/checkout-index: stop using `the_repository`
builtin/for-each-ref: stop using `the_repository`
builtin/ls-files: stop using `the_repository`
builtin/pack-refs: stop using `the_repository`
builtin/send-pack: stop using `the_repository`
builtin/verify-commit: stop using `the_repository`
builtin/verify-tag: stop using `the_repository`
config: teach repo_config to allow `repo` to be NULL
Junio C Hamano [Wed, 26 Mar 2025 07:26:10 +0000 (16:26 +0900)]
Merge branch 'tb/refs-exclude-fixes'
The refname exclusion logic in the packed-ref backend has been
broken for some time, which confused upload-pack to advertise
different set of refs. This has been corrected.
Junio C Hamano [Wed, 26 Mar 2025 07:26:09 +0000 (16:26 +0900)]
Merge branch 'sj/ref-consistency-checks-more'
"git fsck" becomes more careful when checking the refs.
* sj/ref-consistency-checks-more:
builtin/fsck: add `git refs verify` child process
packed-backend: check whether the "packed-refs" is sorted
packed-backend: add "packed-refs" entry consistency check
packed-backend: check whether the refname contains NUL characters
packed-backend: add "packed-refs" header consistency check
packed-backend: check if header starts with "# pack-refs with: "
packed-backend: check whether the "packed-refs" is regular file
builtin/refs: get worktrees without reading head information
t0602: use subshell to ensure working directory unchanged
Elijah Newren [Thu, 13 Mar 2025 02:46:41 +0000 (02:46 +0000)]
am: switch from merge_recursive_generic() to merge_ort_generic()
Switch from merge-recursive to merge-ort. Adjust the following
testcases due to the switch:
* t4151: This test left an untracked file in the way of the merge.
merge-recursive could only sometimes tell when untracked files were
in the way, and by the time it discovers others, it has already made
too many changes to back out of the merge. So, instead of writing the
results to e.g. 'file1' it would instead write them to
'file1~branch1'. This is confusing for users, because they might not
notice 'file1~branch1' and accidentally add and commit 'file1'.
In contrast, merge-ort correctly notices the file in the way before
making any changes and aborts. Since this test didn't care about the
file in the way, just remove it before calling git-am.
* t4255: Usage of merge-ort allows us to change two known failures into
successes.
* t6427: As noted a few commits ago, the choice of conflict label for
diff3 markers for the ancestor commit was previously handled by
merge-recursive.c rather than by callers. Since that has now changed,
`git am` needs to specify that label. Although the previous conflict
label ("constructed merge base") was already fairly somewhat slanted
towards `git am`, let's use wording more along the lines of the
related command-line flag from `git apply` and function involved to
tie it more closely to `git am`.
Signed-off-by: Elijah Newren <newren@gmail.com> Reviewed-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Elijah Newren [Thu, 13 Mar 2025 02:46:40 +0000 (02:46 +0000)]
merge-ort: fix merge.directoryRenames=false
There are two issues here.
First, when merge.directoryRenames is set to false, there are a few code
paths that should be turned off. I missed one; collect_renames() was
still doing some directory rename detection logic unconditionally. It
ended up not having much effect because
get_provisional_directory_renames() was skipped earlier and not setting
up renames->dir_renames, but the code should still be skipped.
Second, the larger issue is that sometimes we get a cached_pair rename
from a previous commit being replayed mapping A->B, but in a subsequent
commit but collect_merge_info() doesn't even recurse into the
directory containing B because there are no source pairings for that
rename that are relevant; we can merge that commit fine without knowing
the rename. But since the cached renames are added to the normal
renames, when we go to process it and find that B is not part of
opt->priv->paths, we hit the assertion error
process_renames: Assertion `newinfo && ~newinfo->merged.clean` failed.
I think we could fix this at the beginning of detect_regular_renames() by
pruning from cached_pairs any entry whose destination isn't in
opt->priv->paths, but it's suboptimal in that we'd kind of like the
cached_pair to be restored afterwards so that it can help the subsequent
commit, but more importantly since it sits at the intersection of
the caching renames optimization and the relevant renames optimization,
and the trivial directory resolution optimization, and I don't currently
have Documentation/technical/remembering-renames.txt fully paged in, I'm
not sure if that's a full solution or a bandaid for the current
testcase. However, since the remembering renames optimization was the
weakest of the set, and the optimization is far less important when
directory rename detection is off (as that implies far fewer potential
renames), let's just use a bigger hammer to ensure this special case is
fixed: turn off the rename caching. We do the same thing already when
we encounter rename/rename(1to1) cases (as per `git grep -3
disabling.the.optimization`, though it uses a slightly different
triggering mechanism since it's trying to affect the next time that
merge_check_renames_reusable() is called), and I think it makes sense
to do the same here.
Signed-off-by: Elijah Newren <newren@gmail.com> Reviewed-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
It is quite a curious bug: the same test case will succeed, without any
assertion, if instead run with `merge.directoryRenames=true`.
Further, the assertion does not manifest while replaying the first
commit, it manifests while replaying the _second_ commit of the commit
range. But it does _not_ manifest when the second commit is replayed
individually.
This would indicate that there is an incomplete rename cache left-over
from the first replayed commit which is being reused for the second
commit, and if directory rename detection is enabled, the missing paths
are somehow regenerated.
Incidentally, the same bug can by triggered by modifying t6429 to switch
from merge.directoryRenames=true to merge.directoryRenames=false.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
[en: tweaked the commit message slightly, including adjusting the
line number of the assertion to the latest version, and the much
later discovery that a simple t6429 tweak would also display the
issue.] Signed-off-by: Elijah Newren <newren@gmail.com> Reviewed-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Elijah Newren [Thu, 13 Mar 2025 02:46:38 +0000 (02:46 +0000)]
merge-ort: support having merge verbosity be set to 0
Various callers such as am & checkout set the merge verbosity to 0 to
avoid having conflict messages printed. While this could be achieved by
avoiding the wrappers from merge-ort-wrappers and instead passing 0 for
display_update_msgs to merge_switch_to_result(), for simplicity of
converting callers simply allow them to also achieve this with the
merge-ort-wrappers by setting verbosity to 0.
Signed-off-by: Elijah Newren <newren@gmail.com> Reviewed-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Elijah Newren [Thu, 13 Mar 2025 02:46:37 +0000 (02:46 +0000)]
merge-ort: allow rename detection to be disabled
When merge-ort was written, I did not at first allow rename detection to
be disabled, because I suspected that most folks disabling rename
detection were doing so solely for performance reasons. Since I put a
lot of working into providing dramatic speedups for rename detection
performance as used by the merge machinery, I wanted to know if there
were still real world repositories where rename detection was
problematic from a performance perspective. We have had years now to
collect such information, and while we never received one, waiting
longer with the option disabled seems unlikely to help surface such
issues at this point. Also, there has been at least one request to
allow rename detection to be disabled for behavioral rather than
performance reasons (see the thread including
https://lore.kernel.org/git/CABPp-BG-Nx6SCxxkGXn_Fwd2wseifMFND8eddvWxiZVZk0zRaA@mail.gmail.com/
), so let's start heeding the config and command line settings.
Signed-off-by: Elijah Newren <newren@gmail.com> Reviewed-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Elijah Newren [Thu, 13 Mar 2025 02:46:36 +0000 (02:46 +0000)]
merge-ort: add new merge_ort_generic() function
merge-recursive.[ch] have three entry points:
* merge_trees()
* merge_recursive()
* merge_recursive_generic()
merge-ort*.[ch] only has equivalents for the first two. Add an
equivalent for the final entry point, so we can switch callers to
use it and remove merge-recursive.[ch].
While porting it over, finally fix the issue with the label for the
ancestor (used when merge.conflictStyle=diff3 as a conflict label).
merge-recursive.c has traditionally not allowed callers to set that
label, but I have found that problematic for years.
(Side note: This function was initially part of the merge-ort rewrite,
but reviewers questioned the ancestor label funnyness which I was
never really happy with anyway. It resulted in me jettisoning it and
hoping at the time that I would eventually be able to force the existing
callers to use some other API. That worked with `git stash`, as per 874cf2a60444 (stash: apply stash using 'merge_ort_nonrecursive()',
2022-05-10), but this API is the most reasonable one for `git am` and
`git merge-recursive`, if we can just allow them some freedom over the
ancestor label.)
The merge_recursive_generic() function did not know whether it was being
invoked by `git stash`, `git merge-recursive`, or `git am`, and the
choice of meaningful ancestor label, when there is a unique ancestor,
varies for these different callers:
* git am: ancestor is a constructed "fake ancestor" that user knows
nothing about and has no access to. (And is different than
the normal thing we mean by a "virtual merge base" which is
the merging of merge bases.)
* git merge-recursive: ancestor might be a tree, but at least it
was one specified by the user (if they invoked
merge-recursive directly)
* git stash: ancestor was the commit serving as the stash base
Thus, using a label like "constructed merge base" (as
merge_recursive_generic() does) presupposes that `git am` is the only
caller; it is incorrect for other callers. This label has thrown me off
more than once. Allow the caller to override when there is a unique
merge base.
Signed-off-by: Elijah Newren <newren@gmail.com> Reviewed-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
refs: reuse iterators when determining refname availability
When verifying whether refnames are available we have to verify whether
any reference exists that is nested under the current reference. E.g.
given a reference "refs/heads/foo", we must make sure that there is no
other reference "refs/heads/foo/*".
This check is performed using a ref iterator with the prefix set to the
nested reference namespace. Until now it used to not be possible to
reseek iterators, so we always had to reallocate the iterator for every
single reference we're about to check. This keeps us from reusing state
that the iterator may have and that may make it work more efficiently.
Refactor the logic to reseek iterators. This leads to a sizeable speedup
with the "reftable" backend:
Benchmark 1: update-ref: create many refs (refformat = reftable, preexisting = 100000, new = 10000, revision = HEAD~)
Time (mean ± σ): 39.8 ms ± 0.9 ms [User: 29.7 ms, System: 9.8 ms]
Range (min … max): 38.4 ms … 42.0 ms 62 runs
Benchmark 2: update-ref: create many refs (refformat = reftable, preexisting = 100000, new = 10000, revision = HEAD)
Time (mean ± σ): 31.9 ms ± 1.1 ms [User: 27.0 ms, System: 4.5 ms]
Range (min … max): 29.8 ms … 34.3 ms 74 runs
Summary
update-ref: create many refs (refformat = reftable, preexisting = 100000, new = 10000, revision = HEAD) ran
1.25 ± 0.05 times faster than update-ref: create many refs (refformat = reftable, preexisting = 100000, new = 10000, revision = HEAD~)
The "files" backend doesn't really show a huge impact:
Benchmark 1: update-ref: create many refs (refformat = files, preexisting = 100000, new = 10000, revision = HEAD~)
Time (mean ± σ): 392.3 ms ± 7.1 ms [User: 59.7 ms, System: 328.8 ms]
Range (min … max): 384.6 ms … 404.5 ms 10 runs
Benchmark 2: update-ref: create many refs (refformat = files, preexisting = 100000, new = 10000, revision = HEAD)
Time (mean ± σ): 387.7 ms ± 7.4 ms [User: 54.6 ms, System: 329.6 ms]
Range (min … max): 377.0 ms … 397.7 ms 10 runs
Summary
update-ref: create many refs (refformat = files, preexisting = 100000, new = 10000, revision = HEAD) ran
1.01 ± 0.03 times faster than update-ref: create many refs (refformat = files, preexisting = 100000, new = 10000, revision = HEAD~)
This is mostly because it is way slower to begin with because it has to
create a separate file for each new reference, so the milliseconds we
shave off by reseeking the iterator doesn't really translate into a
significant relative improvement.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
refs/iterator: implement seeking for files iterators
Implement seeking for "files" iterators. As we simply use a ref-cache
iterator under the hood the implementation is straight-forward. Note
that we do not implement seeking on reflog iterators, same as with the
"reftable" backend.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
refs/iterator: implement seeking for packed-ref iterators
Implement seeking of `packed-ref` iterators. The implementation is again
straight forward, except that we cannot continue to use the prefix
iterator as we would otherwise not be able to reseek the iterator
anymore in case one first asks for an empty and then for a non-empty
prefix. Instead, we open-code the logic to in `advance()`.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
refs/iterator: implement seeking for ref-cache iterators
Implement seeking of ref-cache iterators. This is done by splitting most
of the logic to seek iterators out of `cache_ref_iterator_begin()` and
putting it into `cache_ref_iterator_seek()` so that we can reuse the
logic.
Note that we cannot use the optimization anymore where we return an
empty ref iterator when there aren't any references, as otherwise it
wouldn't be possible to reseek the iterator to a different prefix that
may exist. This shouldn't be much of a performance concern though as we
now start to bail out early in case `advance()` sees that there are no
more directories to be searched.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
refs/iterator: implement seeking for reftable iterators
Implement seeking of reftable iterators. As the low-level reftable
iterators already support seeking this change is straight-forward. Two
notes though:
- We do not support seeking on reflog iterators. It is unclear what
seeking would even look like in this context, as you typically would
want to seek to a specific entry in the reflog for a specific ref.
There is currently no use case for this, but if one arises in the
future, we can still implement seeking at that later point.
- We start to check whether `reftable_stack_init_ref_iterator()` is
successful.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
refs/iterator: implement seeking for merged iterators
Implement seeking on merged iterators. The implementation is rather
straight forward, with the only exception that we must not deallocate
the underlying iterators once they have been exhausted.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
refs/iterator: provide infrastructure to re-seek iterators
Reftable iterators need to be scrapped after they have either been
exhausted or aren't useful to the caller anymore, and it is explicitly
not possible to reuse them for iterations. But enabling for reuse of
iterators may allow us to tune them by reusing internal state of an
iterator. The reftable iterators for example can already be reused
internally, but we're not able to expose this to any users outside of
the reftable backend.
Introduce a new `.seek` function in the ref iterator vtable that allows
callers to seek an iterator multiple times. It is expected to be
functionally the same as calling `refs_ref_iterator_begin()` with a
different (or the same) prefix.
Note that it is not possible to adjust parameters other than the seeked
prefix for now, so exclude patterns, trimmed prefixes and flags will
remain unchanged. We do not have a usecase for changing these parameters
right now, but if we ever find one we can adapt accordingly.
Implement the callback for trivial cases. The other iterators will be
implemented in subsequent commits.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
The ref and reflog iterators have their lifecycle attached to iteration:
once the iterator reaches its end, it is automatically released and the
caller doesn't have to care about that anymore. When the iterator should
be released before it has been exhausted, callers must explicitly abort
the iterator via `ref_iterator_abort()`.
This lifecycle is somewhat unusual in the Git codebase and creates two
problems:
- Callsites need to be very careful about when exactly they call
`ref_iterator_abort()`, as calling the function is only valid when
the iterator itself still is. This leads to somewhat awkward calling
patterns in some situations.
- It is impossible to reuse iterators and re-seek them to a different
prefix. This feature isn't supported by any iterator implementation
except for the reftable iterators anyway, but if it was implemented
it would allow us to optimize cases where we need to search for
specific references repeatedly by reusing internal state.
Detangle the lifecycle from iteration so that we don't deallocate the
iterator anymore once it is exhausted. Instead, callers are now expected
to always call a newly introduce `ref_iterator_free()` function that
deallocates the iterator and its internal state.
Note that the `dir_iterator` is somewhat special because it does not
implement the `ref_iterator` interface, but is only used to implement
other iterators. Consequently, we have to provide `dir_iterator_free()`
instead of `dir_iterator_release()` as the allocated structure itself is
managed by the `dir_iterator` interfaces, as well, and not freed by
`ref_iterator_free()` like in all the other cases.
While at it, drop the return value of `ref_iterator_abort()`, which
wasn't really required by any of the iterator implementations anyway.
Furthermore, stop calling `base_ref_iterator_free()` in any of the
backends, but instead call it in `ref_iterator_free()`.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
refs: stop re-verifying common prefixes for availability
One of the checks done by `refs_verify_refnames_available()` is whether
any of the prefixes of a reference already exists. For example, given a
reference "refs/heads/main", we'd check whether "refs/heads" or "refs"
already exist, and if so we'd abort the transaction.
When updating multiple references at once, this check is performed for
each of the references individually. Consequently, because references
tend to have common prefixes like "refs/heads/" or refs/tags/", we
evaluate the availability of these prefixes repeatedly. Naturally this
is a waste of compute, as the availability of those prefixes should in
general not change in the middle of a transaction. And if it would,
backends would notice at a later point in time.
Optimize this pattern by storing prefixes in a `strset` so that we can
trivially track those prefixes that we have already checked. This leads
to a significant speedup with the "reftable" backend when creating many
references that all share a common prefix:
Benchmark 1: update-ref: create many refs (refformat = reftable, preexisting = 100000, new = 10000, revision = HEAD~)
Time (mean ± σ): 63.1 ms ± 1.8 ms [User: 41.0 ms, System: 21.6 ms]
Range (min … max): 60.6 ms … 69.5 ms 38 runs
Benchmark 2: update-ref: create many refs (refformat = reftable, preexisting = 100000, new = 10000, revision = HEAD)
Time (mean ± σ): 40.0 ms ± 1.3 ms [User: 29.3 ms, System: 10.3 ms]
Range (min … max): 38.1 ms … 47.3 ms 61 runs
Summary
update-ref: create many refs (refformat = reftable, preexisting = 100000, new = 10000, revision = HEAD) ran
1.58 ± 0.07 times faster than update-ref: create many refs (refformat = reftable, preexisting = 100000, new = 10000, revision = HEAD~)
For the "files" backend we see an improvement, but a much smaller one:
Benchmark 1: update-ref: create many refs (refformat = files, preexisting = 100000, new = 10000, revision = HEAD~)
Time (mean ± σ): 395.8 ms ± 5.3 ms [User: 63.6 ms, System: 330.5 ms]
Range (min … max): 387.0 ms … 404.6 ms 10 runs
Benchmark 2: update-ref: create many refs (refformat = files, preexisting = 100000, new = 10000, revision = HEAD)
Time (mean ± σ): 386.0 ms ± 4.0 ms [User: 51.5 ms, System: 332.8 ms]
Range (min … max): 380.8 ms … 392.6 ms 10 runs
Summary
update-ref: create many refs (refformat = files, preexisting = 100000, new = 10000, revision = HEAD) ran
1.03 ± 0.02 times faster than update-ref: create many refs (refformat = files, preexisting = 100000, new = 10000, revision = HEAD~)
This change also leads to a modest improvement when writing references
with "initial" semantics, for example when migrating references. The
following benchmarks are migrating 1m references from the "reftable" to
the "files" backend:
Benchmark 1: migrate reftable:files (refcount = 1000000, revision = HEAD~)
Time (mean ± σ): 836.6 ms ± 5.6 ms [User: 645.2 ms, System: 185.2 ms]
Range (min … max): 829.6 ms … 845.9 ms 10 runs
Benchmark 2: migrate reftable:files (refcount = 1000000, revision = HEAD)
Time (mean ± σ): 759.8 ms ± 5.1 ms [User: 574.9 ms, System: 178.9 ms]
Range (min … max): 753.1 ms … 768.8 ms 10 runs
Summary
migrate reftable:files (refcount = 1000000, revision = HEAD) ran
1.10 ± 0.01 times faster than migrate reftable:files (refcount = 1000000, revision = HEAD~)
And vice versa:
Benchmark 1: migrate files:reftable (refcount = 1000000, revision = HEAD~)
Time (mean ± σ): 870.7 ms ± 5.7 ms [User: 735.2 ms, System: 127.4 ms]
Range (min … max): 861.6 ms … 883.2 ms 10 runs
Benchmark 2: migrate files:reftable (refcount = 1000000, revision = HEAD)
Time (mean ± σ): 799.1 ms ± 8.5 ms [User: 661.1 ms, System: 130.2 ms]
Range (min … max): 787.5 ms … 812.6 ms 10 runs
Summary
migrate files:reftable (refcount = 1000000, revision = HEAD) ran
1.09 ± 0.01 times faster than migrate files:reftable (refcount = 1000000, revision = HEAD~)
The impact here is significantly smaller given that we don't perform any
reference reads with "initial" semantics, so the speedup only comes from
us doing less string list lookups.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
refs/files: batch refname availability checks for initial transactions
The "files" backend explicitly carves out special logic for its initial
transaction so that it can avoid writing out every single reference as
a loose reference. While the assumption is that there shouldn't be any
preexisting references, we still have to verify that none of the newly
written references will conflict with any other new reference in the
same transaction.
Refactor the initial transaction to use batched refname availability
checks. This does not yet have an effect on performance as we still call
`refs_verify_refname_available()` in a loop. But this will change in
subsequent commits and then impact performance when cloning a repository
with many references or when migrating references to the "files" format.
This will improve performance when cloning a repository with many
references or when migrating references from any format to the "files"
format once the availability checks have learned to optimize checks for
many references in a subsequent commit.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
refs/files: batch refname availability checks for normal transactions
Same as the "reftable" backend that we have adapted in the preceding
commit to use batched refname availability checks we can also do so for
the "files" backend. Things are a bit more intricate here though, as we
call `refs_verify_refname_available()` in a set of different contexts:
1. `lock_raw_ref()` when it hits either EEXISTS or EISDIR when creating
a new reference, mostly to create a nice, user-readable error
message. This is nothing we have to care about too much, as we only
hit this code path at most once when we hit a conflict.
2. `lock_raw_ref()` when it _could_ create the lockfile to check
whether it is conflicting with any packed refs. In the general case,
this code path will be hit once for every (successful) reference
update.
3. `lock_ref_oid_basic()`, but it is only executed when copying or
renaming references or when expiring reflogs. It will thus not be
called in contexts where we have many references queued up.
4. `refs_refname_ref_available()`, but again only when copying or
renaming references. It is thus not interesting due to the same
reason as the previous case.
5. `files_transaction_finish_initial()`, which is only executed when
creating a new repository or migrating references.
So out of these, only (2) and (5) are viable candidates to use the
batched checks.
Adapt `lock_raw_ref()` accordingly by queueing up reference names that
need to be checked for availability and then checking them after we have
processed all updates. This check is done before we (optionally) lock
the `packed-refs` file, which is somewhat flawed because it means that
the `packed-refs` could still change after the availability check and
thus create an undetected conflict. But unconditionally locking the file
would change semantics that users are likely to rely on, so we keep the
current locking sequence intact, even if it's suboptmial.
The refactoring of `files_transaction_finish_initial()` will be done in
the next commit.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Refactor the "reftable" backend to batch the availability check for
refnames. This does not yet have an effect on performance as
`refs_verify_refnames_available()` effectively still performs the
availability check for each refname individually. But this will be
optimized in subsequent commits, where we learn to optimize some parts
of the logic when checking multiple refnames for availability.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
refs: introduce function to batch refname availability checks
The `refs_verify_refname_available()` functions checks whether a
reference update can be committed or whether it would conflict with
either a prefix or suffix thereof. This function needs to be called once
per reference that one wants to check, which requires us to redo a
couple of checks every time the function is called.
Introduce a new function `refs_verify_refnames_available()` that does
the same, but for a list of references. For now, the new function uses
the exact same implementation, except that we loop through all refnames
provided by the caller. This will be tuned in subsequent commits.
The existing `refs_verify_refname_available()` function is reimplemented
on top of the new function. As such, the diff is best viewed with the
`--ignore-space-change option`.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
builtin/update-ref: skip ambiguity checks when parsing object IDs
Most of the commands in git-update-ref(1) accept an old and/or new
object ID to update a specific reference to. These object IDs get parsed
via `repo_get_oid()`, which not only handles plain object IDs, but also
those that have a suffix like "~" or "^2". More surprisingly though, it
even knows to resolve arbitrary revisions, despite the fact that its
manpage does not mention this fact even once.
One consequence of this is that we also check for ambiguous references:
when parsing a full object ID where the DWIM mechanism would also cause
us to resolve it as a branch, we'd end up printing a warning. While this
check makes sense to have in general, it is arguably less useful in the
context of git-update-ref(1). This is due to multiple reasons:
- The manpage is explicitly structured around object IDs. So if we see
a fully blown object ID, the intent should be quite clear in
general.
- The command is part of our plumbing layer and not a tool that users
would generally use in interactive workflows. As such, the warning
will likely not be visible to anybody in the first place.
- Users can and should use the fully-qualified refname in case there
is any potential for ambiguity. And given that this command is part
of our plumbing layer, one should always try to be as defensive as
possible and use fully-qualified refnames.
Furthermore, this check can be quite expensive when updating lots of
references via `--stdin`, because we try to read multiple references per
object ID that we parse according to the DWIM rules. This effect can be
seen both with the "files" and "reftable" backend.
The issue is not unique to git-update-ref(1), but was also an issue in
git-cat-file(1), where it was addressed by disabling the ambiguity check
in 25fba78d36b (cat-file: disable object/refname ambiguity check for
batch mode, 2013-07-12).
Disable the warning in git-update-ref(1), which provides a significant
speedup with both backends. The user-visible outcome is unchanged even
when ambiguity exists, except that we don't show the warning anymore.
The following benchmark creates 10000 new references with a 100000
preexisting refs with the "files" backend:
Benchmark 1: update-ref: create many refs (refformat = files, preexisting = 100000, new = 10000, revision = HEAD~)
Time (mean ± σ): 467.3 ms ± 5.1 ms [User: 100.0 ms, System: 365.1 ms]
Range (min … max): 461.9 ms … 479.3 ms 10 runs
Benchmark 2: update-ref: create many refs (refformat = files, preexisting = 100000, new = 10000, revision = HEAD)
Time (mean ± σ): 394.1 ms ± 5.8 ms [User: 63.3 ms, System: 327.6 ms]
Range (min … max): 384.9 ms … 405.7 ms 10 runs
Summary
update-ref: create many refs (refformat = files, preexisting = 100000, new = 10000, revision = HEAD) ran
1.19 ± 0.02 times faster than update-ref: create many refs (refformat = files, preexisting = 100000, new = 10000, revision = HEAD~)
And with the "reftable" backend:
Benchmark 1: update-ref: create many refs (refformat = reftable, preexisting = 100000, new = 10000, revision = HEAD~)
Time (mean ± σ): 146.9 ms ± 2.2 ms [User: 90.4 ms, System: 56.0 ms]
Range (min … max): 142.7 ms … 150.8 ms 19 runs
Benchmark 2: update-ref: create many refs (refformat = reftable, preexisting = 100000, new = 10000, revision = HEAD)
Time (mean ± σ): 63.2 ms ± 1.1 ms [User: 41.0 ms, System: 21.8 ms]
Range (min … max): 61.1 ms … 66.6 ms 41 runs
Summary
update-ref: create many refs (refformat = reftable, preexisting = 100000, new = 10000, revision = HEAD) ran
2.32 ± 0.05 times faster than update-ref: create many refs (refformat = reftable, preexisting = 100000, new = 10000, revision = HEAD~)
Note that the absolute improvement with both backends is roughly in the
same ballpark, but the relative improvement for the "reftable" backend
is more significant because writing the new table to disk is faster in
the first place.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
object-name: allow skipping ambiguity checks in `get_oid()` family
When reading an object ID via `get_oid_basic()` or any of its related
functions we perform a check whether the object ID is ambiguous, which
can be the case when a reference with the same name exists. While the
check is generally helpful, there are cases where it only adds to the
runtime overhead without providing much of a benefit.
Add a new flag that allows us to disable the check. The flag will be
used in a subsequent commit.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Introduce a new function `repo_get_oid_with_flags()`. This function
behaves the same as `repo_get_oid()`, except that it takes an extra
`flags` parameter that it ends up passing to `get_oid_with_context()`.
This function will be used in a subsequent commit.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Mon, 10 Mar 2025 15:57:46 +0000 (16:57 +0100)]
fast-export, fast-import: add support for signed-commits
fast-export has a --signed-tags= option that controls how to handle tag
signatures. However, there is no equivalent for commit signatures; it
just silently strips the signature out of the commit (analogously to
--signed-tags=strip).
While signatures are generally problematic for fast-export/fast-import
(because hashes are likely to change), if they're going to support tag
signatures, there's no reason to not also support commit signatures.
So, implement a --signed-commits= option that mirrors the --signed-tags=
option.
On the fast-export side, try to be as much like signed-tags as possible,
in both implementation and in user-interface. This will change the
default behavior to '--signed-commits=abort' from what is now
'--signed-commits=strip'. In order to provide an escape hatch for users
of third-party tools that call fast-export and do not yet know of the
--signed-commits= option, add an environment variable
'FAST_EXPORT_SIGNED_COMMITS_NOABORT=1' that changes the default to
'--signed-commits=warn-strip'.
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Mon, 10 Mar 2025 15:57:45 +0000 (16:57 +0100)]
fast-export: do not modify memory from get_commit_buffer
fast-export's helper function find_encoding() takes a `const char *`, but
modifies that memory despite the `const`. Ultimately, this memory came
from get_commit_buffer(), and you're not supposed to modify the memory
that you get from get_commit_buffer().
So, get rid of find_encoding() in favor of commit.h:find_commit_header(),
which gives back a string length, rather than mutating the memory to
insert a '\0' terminator.
Because find_commit_header() detects the "\n\n" string that separates the
headers and the commit message, move the call to be above the
`message = strstr(..., "\n\n")` call. This helps readability, and allows
for the value of `encoding` to be used for a better value of "..." so that
the same memory doesn't need to be checked twice. Introduce a
`commit_buffer_cursor` variable to avoid writing an awkward
`encoding ? encoding + encoding_len : committer_end` expression.
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Mon, 10 Mar 2025 15:57:44 +0000 (16:57 +0100)]
git-fast-export.adoc: clarify why 'verbatim' may not be a good idea
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Mon, 10 Mar 2025 15:57:43 +0000 (16:57 +0100)]
fast-export: rename --signed-tags='warn' to 'warn-verbatim'
The --signed-tags= option takes one of five arguments specifying how to
handle signed tags during export. Among these arguments, 'strip' is to
'warn-strip' as 'verbatim' is to 'warn' (the unmentioned argument is
'abort', which stops the fast-export process entirely). That is,
signatures are either stripped or copied verbatim while exporting, with
or without a warning.
Match the pattern and rename 'warn' to 'warn-verbatim' to make it clear
that it instructs fast-export to copy signatures verbatim.
To maintain backwards compatibility, 'warn' is still recognized as
deprecated synonym of 'warn-verbatim'.
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Luke Shumaker [Mon, 10 Mar 2025 15:57:41 +0000 (16:57 +0100)]
git-fast-import.adoc: add missing LF in the BNF
Signed-off-by: Luke Shumaker <lukeshu@datawire.io> Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jean-Noël Avila [Sun, 9 Mar 2025 19:45:11 +0000 (19:45 +0000)]
doc: add a blank line around block delimiters
The documentation is using the historical mode for titles, which is a
setext-style (i.e., two-line) section title.
The issue with this mode is that starting block delimiters (e.g.,
`----`) can be confused with a section title when they are exactly the
same length as the preceding line. In the original documentation, this
is taken care of for English by the writer, but it is not the case for
translations where these delimiters are hidden. A translator can
generate a line that is exactly the same length as the following block
delimiter, which leads to this line being considered as a title.
To safeguard against this issue, add a blank line before and after
block delimiters where block is at root level, else add a "+" line
before block delimiters to link it to the preceding paragraph.
Signed-off-by: Jean-Noël Avila <jn.avila@free.fr> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Martin Ågren [Mon, 10 Mar 2025 11:07:56 +0000 (12:07 +0100)]
git-clone doc: fix indentation
Commit bc26f7690a (clone: make it possible to specify --tags,
2025-02-06) added a new paragraph in the middle of this list item. By
adding an empty line rather than using a list continuation, we broke the
list continuation, with the new paragraph ending up funnily indented.
Restore the chain of list continuations.
Signed-off-by: Martin Ågren <martin.agren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Peter Krefting [Mon, 10 Mar 2025 16:48:34 +0000 (17:48 +0100)]
l10n: sv.po: Update Swedish translation
- Update for 2.49.0.
- Fix numerous typos found by spelling checker.
- Fix more straight quotes.
- Harmonize translation of "blob" (to "blob", not "blobb").
- Harmonize translation of "reflog" (to "referenslogg").
Signed-off-by: Peter Krefting <peter@softwolves.pp.se>
Usman Akinyemi [Fri, 7 Mar 2025 23:35:07 +0000 (05:05 +0530)]
builtin/checkout-index: stop using `the_repository`
Remove the_repository global variable in favor of the repository
argument that gets passed in "builtin/checkout-index.c".
When `-h` is passed to the command outside a Git repository, the
`run_builtin()` will call the `cmd_checkout_index()` function with `repo`
set to NULL and then early in the function, `show_usage_with_options_if_asked()`
call will give the options help and exit.
Pass an instance of "struct index_state" available in the calling
context to both `checkout_all()` and `checkout_file()` to remove their
dependency on the global `the_repository` variable.
Mentored-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Usman Akinyemi <usmanakinyemi202@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Usman Akinyemi [Fri, 7 Mar 2025 23:35:06 +0000 (05:05 +0530)]
builtin/for-each-ref: stop using `the_repository`
Remove the_repository global variable in favor of the repository
argument that gets passed in "builtin/for-each-ref.c".
When `-h` is passed to the command outside a Git repository, the
`run_builtin()` will call the `cmd_for_each_ref()` function with `repo`
set to NULL and then early in the function, `parse_options()` call will
give the options help and exit.
Mentored-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Usman Akinyemi <usmanakinyemi202@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Usman Akinyemi [Fri, 7 Mar 2025 23:35:05 +0000 (05:05 +0530)]
builtin/ls-files: stop using `the_repository`
Remove the_repository global variable in favor of the repository
argument that gets passed in "builtin/ls-files.c".
When `-h` is passed to the command outside a Git repository, the
`run_builtin()` will call the `cmd_ls_files()` function with `repo` set
to NULL and then early in the function, `show_usage_with_options_if_asked()`
call will give the options help and exit.
Pass the repository available in the calling context to both
`expand_objectsize()` and `show_ru_info()` to remove their
dependency on the global `the_repository` variable.
Mentored-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Usman Akinyemi <usmanakinyemi202@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Usman Akinyemi [Fri, 7 Mar 2025 23:35:04 +0000 (05:05 +0530)]
builtin/pack-refs: stop using `the_repository`
Remove the_repository global variable in favor of the repository
argument that gets passed in "builtin/pack-refs.c".
When `-h` is passed to the command outside a Git repository, the
`run_builtin()` will call the `cmd_pack_refs()` function with `repo` set
to NULL and then early in the function, `parse_options()` call will give
the options help and exit.
Mentored-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Usman Akinyemi <usmanakinyemi202@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Usman Akinyemi [Fri, 7 Mar 2025 23:35:03 +0000 (05:05 +0530)]
builtin/send-pack: stop using `the_repository`
Remove the_repository global variable in favor of the repository
argument that gets passed in "builtin/send-pack.c".
When `-h` is passed to the command outside a Git repository, the
`run_builtin()` will call the `cmd_send_pack()` function with `repo` set
to NULL and then early in the function, `parse_options()` call will give
the options help and exit.
Mentored-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Usman Akinyemi <usmanakinyemi202@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Usman Akinyemi [Fri, 7 Mar 2025 23:35:02 +0000 (05:05 +0530)]
builtin/verify-commit: stop using `the_repository`
Remove the_repository global variable in favor of the repository
argument that gets passed in "builtin/verify-commit.c".
When `-h` is passed to the command outside a Git repository, the
`run_builtin()` will call the `cmd_verify_commit()` function with `repo`
set to NULL and then early in the function, `parse_options()` call will
give the options help and exit.
Pass the repository available in the calling context to `verify_commit()`
to remove it's dependency on the global `the_repository` variable.
Mentored-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Usman Akinyemi <usmanakinyemi202@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Usman Akinyemi [Fri, 7 Mar 2025 23:35:01 +0000 (05:05 +0530)]
builtin/verify-tag: stop using `the_repository`
Remove the_repository global variable in favor of the repository
argument that gets passed in "builtin/verify-tag.c".
When `-h` is passed to the command outside a Git repository, the
`run_builtin()` will call the `cmd_verify_tag()` function with `repo` set
to NULL and then early in the function, `parse_options()` call will give
the options help and exit.
Mentored-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Usman Akinyemi <usmanakinyemi202@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Usman Akinyemi [Fri, 7 Mar 2025 23:35:00 +0000 (05:05 +0530)]
config: teach repo_config to allow `repo` to be NULL
The `repo` value can be NULL if a builtin command is run outside
any repository. The current implementation of `repo_config()` will
fail if `repo` is NULL.
If the `repo` is NULL the `repo_config()` can ignore the repository
configuration but it should read the other configuration sources like
the system-side configuration instead of failing.
Teach the `repo_config()` to allow `repo` to be NULL by calling the
`read_very_early_config()` which read config but only enumerate system
and global settings.
This will be useful in the following commits.
Suggested-by: Junio C Hamano <gitster@pobox.com> Mentored-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Usman Akinyemi <usmanakinyemi202@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau [Fri, 7 Mar 2025 23:27:03 +0000 (18:27 -0500)]
fetch: fix following tags when fetching specific OID
In 3f763ddf28 (fetch: set remote/HEAD if it does not exist, 2024-11-22),
unconditionally adds "HEAD" to the list of ref prefixes we send to the
server.
This breaks a core assumption that the list of prefixes we send to the
server is complete. We must either send all prefixes we care about, or
none at all (in the latter case the server then advertises everything).
The tag following code is careful to only add "refs/tags/" to the list
of prefixes if there are already entries in the prefix list. But because
the new code from 3f763ddf28 runs after the tag code, and because it
unconditionally adds to the prefix list, we may end up with a prefix
list that _should_ have "refs/tags/" in it, but doesn't.
When that is the case, the server does not advertise any tags, and our
auto-following breaks because we never learned about any tags in the
first place.
Fix this by only adding "HEAD" to the ref prefixes when we know that we
are already limiting the advertisement. In either case we'll learn about
HEAD (either through the limited advertisement, or implicitly through a
full advertisement).
Reported-by: Igor Todorovski <itodorov@ca.ibm.com> Co-authored-by: Jeff King <peff@peff.net> Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Toon Claes [Fri, 7 Mar 2025 14:18:08 +0000 (15:18 +0100)]
help: print zlib-ng version number
When building against zlib-ng, the header file `zlib.h` is not included,
but `zlib-ng.h` is included instead. It's `zlib.h` that defines
`ZLIB_VERSION` and that macro is used to print out zlib version in
`git-version(1)` with `--build-options`. But when it's not defined, no
version is printed.
`zlib-ng.h` defines another macro: `ZLIBNG_VERSION`. Use that macro to
print the zlib-ng version in `git version --build-options` when it's
set. Otherwise fallback to `ZLIB_VERSION`.
Signed-off-by: Toon Claes <toon@iotcl.com> Helped-by: Patrick Steinhardt <ps@pks.im> Reviewed-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Toon Claes [Fri, 7 Mar 2025 14:18:07 +0000 (15:18 +0100)]
help: include git-zlib.h to print zlib version
In 41f1a8435a (git-compat-util: move include of "compat/zlib.h" into
"git-zlib.h", 2025-01-28) some code was refactored to enable easier
linking against zlib-ng.
This removed `zlib.h` being indirectly included in `help.c`. As this
file uses `ZLIB_VERSION` to print the version number of zlib when
running git-version(1) with `--build-options`, this resulted in a
regression.
Include `git-zlib.h` directly into `help.c` to print zlib version
information. This brings back the zlib version in the output of
`git version --build-options`.
Signed-off-by: Toon Claes <toon@iotcl.com> Reviewed-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano [Thu, 6 Mar 2025 22:06:31 +0000 (14:06 -0800)]
Merge branch 'js/win-2.49-build-fixes'
Hotfix to help building Git-for-Windows.
* js/win-2.49-build-fixes:
cmake: generalize the handling of the `CLAR_TEST_OBJS` list
meson: fix sorting
ident: stop assuming that `gw_gecos` is writable
Junio C Hamano [Thu, 6 Mar 2025 22:06:31 +0000 (14:06 -0800)]
Merge branch 'pw/repo-layout-doc-update'
Some future breaking changes would remove certain parts of the
default repository, which were still described even when the
documents were built for the future with WITH_BREAKING_CHANGES.
* pw/repo-layout-doc-update:
docs: fix repository-layout when building with breaking changes
Elijah Newren [Thu, 6 Mar 2025 15:30:27 +0000 (15:30 +0000)]
merge-ort: fix slightly overzealous assertion for rename-to-self
merge-ort has a number of sanity checks on the file it is processing in
process_renames(). One of these sanity checks was slightly overzealous
because it indirectly assumed that a renamed file always ended up at a
different path than where it started. That is normally an entirely fair
assumption, but directory rename detection can make things interesting.
As a quick refresher, if one side of history renames directory A/ -> B/,
and the other side of history adds new files to A/, then directory
rename detection notices and suggests moving those new files to B/. A
similar thing is done for paths renamed into A/, causing them to be
transitively renamed into B/. But, if the file originally came from B/,
then this can end up causing a file to be renamed back to itself.
It turns out the rest of the code following this assertion handled the
case fine; the assertion was just an extra sanity check, not a rigid
precondition. Therefore, simply adjust the assertion to pass under this
special case as well.
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
t6423: add a testcase causing a failed assertion in process_renames
If one side of history renames a directory A/ -> B/, and the other side
of history adds new files to A/, then directory rename detection notices
and moves or suggests moving those new files to B/. A similar thing is
done for paths renamed into A/, causing them to be transitively renamed
into B/. But, if the file originally came from B/, then this can end up
causing a file to be renamed back to itself. merge-ort crashes under
this special case, due to a slightly overzealous assertion:
Signed-off-by: Dmitry Goncharov <dgoncharov@users.sf.net>
[en: Instead of adding a new testsuite, place it near similar tests in
t6423, adjusting to match the style of those tests. Tweak the commit
message to not repeat the entire testcase, but just describe the bug.
Also update the line number in the error message.] Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau [Thu, 6 Mar 2025 15:34:53 +0000 (10:34 -0500)]
refs.c: stop matching non-directory prefixes in exclude patterns
In the packed-refs backend, our implementation of '--exclude' (dating
back to 59c35fac54 (refs/packed-backend.c: implement jump lists to avoid
excluded pattern(s), 2023-07-10)) considers, for example:
$ git for-each-ref --exclude=refs/heads/ba
to exclude "refs/heads/bar", "refs/heads/baz", and so on.
The files backend, which does not implement '--exclude' (and relies on
the caller to cull out results that don't match) naturally will
enumerate "refs/heads/bar" and so on.
So in the above example, 'for-each-ref' will try and see if
"refs/heads/ba" matches "refs/heads/bar" (since the files backend simply
enumerated every loose reference), and, realizing that it does not
match, output the reference as expected. (A caller that did want to
exclude "refs/heads/bar" and "refs/heads/baz" might instead run "git
for-each-ref --exclude='refs/heads/ba*'").
This can lead to strange behavior, like seeing a different set of
references advertised via 'upload-pack' depending on what set of
references were loose versus packed.
So there is a subtle bug with '--exclude' which is that in the
packed-refs backend we will consider "refs/heads/bar" to be a pattern
match against "refs/heads/ba" when we shouldn't. Likewise, the reftable
backend (which in this case is bug-compatible with the packed backend)
exhibits the same broken behavior.
There are a few ways to fix this. One is to tighten the rules in
cmp_record_to_refname(), which is used to determine the start/end-points
of the jump list used by the packed backend. In this new "strict" mode,
the comparison function would handle the case where we've reached the
end of the pattern by introducing a new check like so:
while (1) {
if (*r1 == '\n')
return *r2 ? -1 : 0;
if (!*r2)
if (strict && *r1 != '/') /* <- here */
return 1;
return start ? 1 : -1;
if (*r1 != *r2)
return (unsigned char)*r1 < (unsigned char)*r2 ? -1 : +1;
r1++;
r2++;
}
(eliding out the rest of cmp_record_to_refname()). Equivalently, we
could teach refs/packed-backend::populate_excluded_jump_list() to append
a trailing '/' if one does not already exist, forcing an exclude pattern
like "refs/heads/ba" to only match "refs/heads/ba/abc" and so forth.
But since the same problem exists in reftable, we can fix both at once
by performing this pre-processing step one layer up in refs.c at the
common entrypoint for the two, which is 'refs_ref_iterator_begin()'.
Since that solution is both the simplest and only requires modification
in one spot, let's normalize exclude patterns so that they end with a
trailing slash. This causes us to unify the behavior between all three
backends.
There is some minor test fallout in the "overlapping excluded regions"
test, which happens to use 'refs/ba' as an exclude pattern, and expects
references under the "refs/heads/bar/*" and "refs/heads/baz/*"
hierarchies to be excluded from the results.
But that test fallout is expected, because the test was codifying the
buggy behavior to begin with, and should have never been written that
way. Split that into its own test (since the range is no longer
overlapping under the stricter interpretation of --exclude patterns
presented here). Create a new test which does have overlapping
regions by using a refs/heads/bar/4/... hierarchy and excluding both
"refs/heads/bar" and "refs/heads/bar/4".
Reported-by: SURA <surak8806@gmail.com> Helped-by: Jeff King <peff@peff.net> Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau [Thu, 6 Mar 2025 15:34:48 +0000 (10:34 -0500)]
refs.c: remove empty '--exclude' patterns
In 59c35fac54 (refs/packed-backend.c: implement jump lists to avoid
excluded pattern(s), 2023-07-10), the packed-refs backend learned how to
construct "jump lists" to avoid enumerating sections of the packed-refs
file that we know the caller is going to throw out anyway.
This process works by finding the start- and end-points (that is, where
in the packed-refs file corresponds to the range we're going to ignore)
for each exclude pattern, then constructing a jump list based on that.
At enumeration time we'll consult the jump list to skip past everything
in the range(s) found in the previous step, saving time when excluding a
large portion of references.
But when there is a --exclude pattern which is just the empty string,
the behavior is a little funky. When we try and exclude the empty
string, the matched range covers the entire packed-refs file, meaning
that we won't output any packed references. But the empty pattern
doesn't actually match any references to begin with! For example, on my
copy of git.git I can do:
$ git for-each-ref '' | wc -l
0
So "git for-each-ref --exclude=''" shouldn't actually remove anything
from the output, and ought to be equivalent to "git for-each-ref". But
it's not, and in fact:
But why does the '--exclude' version output only some of the references
in the repository? Here's a hint:
$ find .git/refs -type f | wc -l
480
Indeed, because the files backend doesn't implement[^1] the same jump
list concept as the packed backend we get the correct result for the
loose references, but none of the packed references.
Since the empty string exclude pattern doesn't match anything, we can
discard them before the packed-refs backend has a chance to even see it
(and likewise for reftable, which also implements a similar concept
since 1869525066 (refs/reftable: wire up support for exclude patterns,
2024-09-16)).
This approach (copying only some of the patterns into a strvec at the
refs.c layer) may seem heavy-handed, but it's setting us up to fix
another bug in the following commit where the fix will involve modifying
the incoming patterns.
[^1]: As noted in 59c35fac54. We technically could avoid opening and
enumerating the contents of, for e.g., "$GIT_DIR/refs/heads/foo/" if
we knew that we were excluding anything under the 'refs/heads/foo'
hierarchy. But the --exclude stuff is all best-effort anyway, since
the caller is expected to cull out any results that they don't want.
Noticed-by: Jeff King <peff@peff.net> Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
cmake: generalize the handling of the `CLAR_TEST_OBJS` list
A late-comer to the v2.49.0 party, `sk/unit-test-oid`, added yet another
array item to `CLAR_TEST_OBJS`, causing the `win+VS build` job to fail
with symptoms like this one:
unit-tests-lib.lib(u-oid-array.obj) : error LNK2019: unresolved
external symbol cl_parse_any_oid referenced in function fill_array
This is a similar scenario to the one that forced me to write 8afda42fce60 (cmake: generalize the handling of the `UNIT_TEST_OBJS`
list, 2024-09-18): The hard-coded echo of `CLAR_TEST_OBJS` in
`CMakeLists.txt` that recapitulates faithfully what was already
hard-coded in `Makefile` would either have to be updated whack-a-mole
style, or generalized.
Just like I chose the latter option for `UNIT_TEST_OBJS`, I now do the
same for `CLAR_TEST_OBJS`.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
In 904339edbd80 (Introduce support for the Meson build system,
2024-12-06) the `meson.build` file was introduced, adding also a
Windows-specific list of source files. This list was obviously meant to
be sorted alphabetically, but there is one mistake. Let's fix that.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
In 590e081dea7c (ident: add NO_GECOS_IN_PWENT for systems without
pw_gecos in struct passwd, 2011-05-19), code was introduced to iterate
over the `gw_gecos` field; The loop variable is of type `char *`, which
assumes that `gw_gecos` is writable.
However, it is not necessarily writable (and it is a bad idea to have it
writable in the first place), so let's switch the loop variable type to
`const char *`.
This is not a new problem, but what is new is the Meson build. While it
does not trigger in CI builds, imitating the commands of
`ci/run-build-and-tests.sh` in a regular Git for Windows SDK (`meson
setup build . --fatal-meson-warnings --warnlevel 2 --werror --wrap-mode
nofallback -Dfuzzers=true` followed by `meson compile -C build --`
results in this beautiful error:
"cc" [...] -o libgit.a.p/ident.c.obj "-c" ../ident.c
../ident.c: In function 'copy_gecos':
../ident.c:68:18: error: assignment discards 'const' qualifier from pointer target type [-Werror=discarded-qualifiers]
68 | for (src = get_gecos(w); *src && *src != ','; src++) {
| ^
cc1.exe: all warnings being treated as errors
Now, why does this not trigger in CI? The answer is as simple as it is
puzzling: The `win+Meson` job completely side-steps Git for Windows'
development environment, opting instead to use the GCC that is on the
`PATH` in GitHub-hosted `windows-latest` runners. That GCC is pinned to
v12.2.0 and targets the UCRT (unlikely to change any time soon, see
https://github.com/actions/runner-images/blob/win25/20250303.1/images/windows/toolsets/toolset-2022.json#L132-L141).
That is in stark contrast to Git for Windows, which uses GCC v14.2.0 and
targets MSVCRT. Git for Windows' `Makefile`-based build also obviously
uses different compiler flags, otherwise this compile error would have
had plenty of opportunity in almost 14 years to surface.
In other words, contrary to my expectations, the `win+Meson` job is
ill-equipped to replace the `win build` job because it exercises a
completely different tool version/compiler flags vector than what Git
for Windows needs.
Nevertheless, there is currently this huge push, including breaking
changes after -rc1 and all, for switching to Meson. Therefore, we need
to make it work, somehow, even in Git for Windows' SDK, hence this
patch, at this point in time.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano [Wed, 5 Mar 2025 18:37:44 +0000 (10:37 -0800)]
Merge branch 'cc/lop-remote'
Large-object promisor protocol extension.
* cc/lop-remote:
doc: add technical design doc for large object promisors
promisor-remote: check advertised name or URL
Add 'promisor-remote' capability to protocol v2
Junio C Hamano [Wed, 5 Mar 2025 18:37:43 +0000 (10:37 -0800)]
Merge branch 'sk/unit-test-oid'
Convert a few unit tests to the clar framework.
* sk/unit-test-oid:
t/unit-tests: convert oidtree test to use clar test framework
t/unit-tests: convert oidmap test to use clar test framework
t/unit-tests: convert oid-array test to use clar test framework
t/unit-tests: implement clar specific oid helper functions
Junio C Hamano [Wed, 5 Mar 2025 18:37:43 +0000 (10:37 -0800)]
Merge branch 'ps/path-sans-the-repository'
The path.[ch] API takes an explicit repository parameter passed
throughout the callchain, instead of relying on the_repository
singleton instance.
* ps/path-sans-the-repository:
path: adjust last remaining users of `the_repository`
environment: move access to "core.sharedRepository" into repo settings
environment: move access to "core.hooksPath" into repo settings
repo-settings: introduce function to clear struct
path: drop `git_path()` in favor of `repo_git_path()`
rerere: let `rerere_path()` write paths into a caller-provided buffer
path: drop `git_common_path()` in favor of `repo_common_path()`
worktree: return allocated string from `get_worktree_git_dir()`
path: drop `git_path_buf()` in favor of `repo_git_path_replace()`
path: drop `git_pathdup()` in favor of `repo_git_path()`
path: drop unused `strbuf_git_path()` function
path: refactor `repo_submodule_path()` family of functions
submodule: refactor `submodule_to_gitdir()` to accept a repo
path: refactor `repo_worktree_path()` family of functions
path: refactor `repo_git_path()` family of functions
path: refactor `repo_common_path()` family of functions
Phillip Wood [Wed, 5 Mar 2025 10:42:37 +0000 (10:42 +0000)]
docs: fix repository-layout when building with breaking changes
Since commit 8ccc75c2452 (remote: announce removal of "branches/" and
"remotes/", 2025-01-22) enabling WITH_BREAKING_CHANGES when building git
removes support for reading branches from ".git/branches" and remotes
from ".git/remotes". However those locations are still documented in
gitrepository-layout.adoc even though the build does not support them.
Rectify this by adding a new document attribute "with-breaking-changes"
and use it to make the inclusion of those sections of the documentation
conditional. Note that the name of the attribute does not match the test
prerequisite WITHOUT_BREAKING_CHANGES added in c5bc9a7f94a (Makefile:
wire up build option for deprecated features, 2025-01-22). This is to
avoid the awkward double negative ifndef::without_breaking_changes for
documentation that should be included when WITH_BREAKING_CHANGES is
enabled. The test prerequisite will be renamed to match the
documentation attribute in a future patch series.
Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk> Signed-off-by: Junio C Hamano <gitster@pobox.com>