The process for reading the index into memory from disk is to first read its
contents into a single memory-mapped file buffer (type 'char *'), then
sequentially convert each on-disk index entry into a corresponding incore
'cache_entry'. To access the contents of the on-disk entry for processing, a
moving pointer within the memory-mapped file is cast to type 'struct
ondisk_cache_entry *'.
In index v4, the entries in the on-disk index file are written *without*
aligning their first byte to a 4-byte boundary; entries are a variable
length (depending on the entry name and whether or not extended flags are
used). As a result, casting the 'char *' buffer pointer to 'struct
ondisk_cache_entry *' then accessing its contents in a 'SANITIZE=undefined'
build can trigger the following error:
read-cache.c:1886:46: runtime error: member access within misaligned
address <address> for type 'struct ondisk_cache_entry', which requires 4
byte alignment
Avoid this error by reading fields directly from the 'char *' buffer, using
the 'offsetof' individual fields in 'struct ondisk_cache_entry'.
Additionally, add documentation describing why the new approach avoids the
misaligned address error, as well as advice on how to improve the
implementation in the future.
Reported-by: Jeff King <peff@peff.net>
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In the previous commit, we fixed a segmentation fault when a tree object
could not be written.
However, before the tree object is written, `merge-ort` wants to write
out a blob object (except in cases where the merge results in a blob
that already exists in the database). And this can fail, too, but we
ignore that write failure so far.
Let's pay close attention and error out early if the blob could not be
written. This reduces the error output of t4301.25 ("merge-ort fails
gracefully in a read-only repository") from:
error: insufficient permission for adding an object to repository database ./objects
error: error: Unable to add numbers to database
error: insufficient permission for adding an object to repository database ./objects
error: error: Unable to add greeting to database
error: insufficient permission for adding an object to repository database ./objects
fatal: failure to merge
to:
error: insufficient permission for adding an object to repository database ./objects
error: error: Unable to add numbers to database
fatal: failure to merge
This is _not_ just a cosmetic change: Even though one might assume that
the operation would have failed anyway at the point when the new tree
object is written (and the corresponding tree object _will_ be new if it
contains a blob that is new), but that is not so: As pointed out by
Elijah Newren, when Git has previously been allowed to add loose objects
via `sudo` calls, it is very possible that the blob object cannot be
written (because the corresponding `.git/objects/??/` directory may be
owned by `root`) but the tree object can be written (because the
corresponding objects directory is owned by the current user). This
would result in a corrupt repository because it is missing the blob
object, and with this here patch we prevent that.
Note: This patch adjusts two variable declarations from `unsigned` to
`int` because their purpose is to hold the return value of
`handle_content_merge()`, which is of type `int`. The existing users of
those variables are only interested whether that variable is zero or
non-zero, therefore this type change does not affect the existing code.
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If the blob/tree objects cannot be written, we really need the merge
operations to fail, and not to continue (and then try to access the tree
object which is however still set to `NULL`).
Let's stop ignoring the return value of `write_object_file()` and
`write_tree()` and set `clean = -1` in the error case.
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We have small updates since -rc1 but none of them is about a new
thing and there is no updates to the release notes.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The for_each_string_list_item() macro takes a string_list and
automatically constructs a for loop to iterate over its contents. This
macro will segfault if the list is non-NULL.
We cannot change the macro to be careful around NULL values because
there are many callers that use the address of a local variable, which
will never be NULL and will cause compile errors with -Werror=address.
For now, leave a documentation comment to try to avoid mistakes in the
future where a caller does not check for a NULL list.
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The 'git maintenance [un]register' commands set or unset the multi-
valued maintenance.repo config key with the absolute path of the current
repository. These are set in the global config file.
Instead of calling a subcommand and creating a new process, create the
proper API calls to git_config_set_multivar_in_file_gently(). It
requires loading the filename for the global config file (and erroring
out if now $HOME value is set). We also need to be careful about using
CONFIG_REGEX_NONE when adding the value and using
CONFIG_FLAGS_FIXED_VALUE when removing the value. In both cases, we
check that the value already exists (this check already existed for
'unregister').
Also, remove the transparent translation of the error code from the
config API to the exit code of 'git maintenance'. Instead, use die() to
recover from failures at that level. In the case of 'unregister
--force', allow the CONFIG_NOTHING_SET error code to be a success. This
allows a possible race where another process removes the config value.
The end result is that the config value is not set anymore, so we can
treat this as a success.
Reported-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The 'scalar unregister' command removes a repository from the list of
registered Scalar repositories and removes it from the list of
repositories registered for background maintenance. If the repository
was not already registered for background maintenance, then the command
fails, even if the repository was still registered as a Scalar
repository.
After using 'scalar clone' or 'scalar register', the repository would be
enrolled in background maintenance since those commands run 'git
maintenance start'. If the user runs 'git maintenance unregister' on
that repository, then it is still in the list of repositories which get
new config updates from 'scalar reconfigure'. The 'scalar unregister'
command would fail since 'git maintenance unregister' would fail.
Further, the add_or_remove_enlistment() method in scalar.c already has
this idempotent nature built in as an expectation since it returns zero
when the scalar.repo list already has the proper containment of the
repository.
The previous change added the 'git maintenance unregister --force'
option, so use it within 'scalar unregister' to make it idempotent.
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The 'git maintenance unregister' subcommand has a step that removes the
current repository from the multi-valued maitenance.repo config key.
This fails if the repository is not listed in that key. This makes
running 'git maintenance unregister' twice result in a failure in the
second instance.
This failure exit code is helpful, but its message is not. Add a new
die() message that explicitly calls out the failure due to the
repository not being registered.
In some cases, users may want to run 'git maintenance unregister' just
to make sure that background jobs will not start on this repository, but
they do not want to check to see if it is registered first. Add a new
'--force' option that will siltently succeed if the repository is not
already registered.
Also add an extra test of 'git maintenance unregister' at a point where
there are no registered repositories. This should fail without --force.
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The trace2 region around the call to lazy_bitmap_for_commit() in
bitmap_for_commit() was added in 28cd730680 (pack-bitmap: prepare to
read lookup table extension, 2022-08-14). While adding trace2 regions is
typically helpful for tracking performance, this method is called
possibly thousands of times as a commit walk explores commit history
looking for a matching bitmap. When trace2 output is enabled, this
region is emitted many times and performance is throttled by that
output.
For now, remove these regions entirely.
This is a critical path, and it would be valuable to measure that the
time spent in bitmap_for_commit() does not increase when using the
commit lookup table. The best way to do that would be to use a mechanism
that sums the time spent in a region and reports a single value at the
end of the process. This technique was introduced but not merged by [1]
so maybe this example presents some justification to revisit that
approach.
[1] https://lore.kernel.org/git/pull.1099.v2.git.1640720202.gitgitgadget@gmail.com/
To help with the 'git blame' output in this region, add a comment that
warns against adding a trace2 region. Delete a test from t5310 that used
that trace output to check that this lookup optimization was activated.
To create this kind of test again in the future, the stopwatch traces
mentioned earlier could be used as a signal that we activated this code
path.
Helpedy-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In 2708ce62d2 (branch: sort detached HEAD based on a flag, 2021-01-07) a
call to wt_status_state_free_buffers, responsible of freeing the
resources that could be allocated in the local struct wt_status_state
state, was eliminated.
The call to wt_status_state_free_buffers was introduced in 962dd7ebc3
(wt-status: introduce wt_status_state_free_buffers(), 2020-09-27). This
commit brings back that call in get_head_description.
Signed-off-by: Rubén Justo <rjusto@gmail.com>
Reviewed-by: Martin Ågren <martin.agren@gmail.com>
Acked-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Commit 68d5d03bc4 (rebase: teach --autosquash to match on sha1 in
addition to message, 2010-11-04) taught autosquash to recognize
subjects like "fixup! 7a235b" where 7a235b is an OID-prefix. It
actually did more than advertised: 7a235b can be an arbitrary
commit-ish (as long as it's not trailed by spaces).
Accidental(?) use of this secret feature revealed a bug where we
would silently drop a fixup commit. The bug can also be triggered
when using an OID-prefix but that's unlikely in practice.
Let the commit with subject "fixup! main" be the tip of the "main"
branch. When computing the fixup target for this commit, we find
the commit itself. This is wrong because, by definition, a fixup
target must be an earlier commit in the todo list. We wrongly find
the current commit because we added it to the todo list prematurely.
Avoid these fixup-cycles by only adding the current commit to the
todo list after we have finished looking for the fixup target.
Reported-by: Erik Cervin Edin <erik@cervined.in>
Signed-off-by: Johannes Altmanninger <aclopte@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The text of this message was changed in commit
71076d0edd to avoid making any
suggestion about which strategy is better for the situation at hand.
Update the Franch translation to match.
Signed-off-by: Alex Henrie <alexhenrie24@gmail.com>
We attribute each documentation text file to a man section by finding a
line in the file that looks like "gitfoo(<digit>)". Commit cc75e556a9
("scalar: add to 'git help -a' command list", 2022-09-02) updated this
logic to look not only for "gitfoo" but also "scalarfoo". In doing so,
it forgot to account for the fact that after the updated regex has found
a match, the man section is no longer to be found in `$1` but now lives
in `$2`.
This makes our git(1) manpage look as follows:
Main porcelain commands
git-add(git)
Add file contents to the index.
[...]
gitk(git)
The Git repository browser.
scalar(scalar)
A tool for managing large Git repositories.
Restore the man sections by not capturing the (git|scalar) part of the
match into `$1`.
As noted by Ævar [1], we could even match any "foo" rather than just
"gitfoo" and "scalarfoo", but that's a larger change. For now, just fix
the regression in cc75e556a9.
[1] https://lore.kernel.org/git/220923.86wn9u4joo.gmgdl@evledraar.gmail.com/#t
Helped-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Turn on sparse index and remove ensure_full_index().
Before this patch, `git-grep` utilizes the ensure_full_index() method to
expand the index and search all the entries. Because this method
requires walking all the trees and constructing the index, it is the
slow part within the whole command.
To achieve better performance, this patch uses grep_tree() to search the
sparse directory entries and get rid of the ensure_full_index() method.
Why grep_tree() is a better choice over ensure_full_index()?
1) grep_tree() is as correct as ensure_full_index(). grep_tree() looks
into every sparse-directory entry (represented by a tree) recursively
when looping over the index, and the result of doing so matches the
result of expanding the index.
2) grep_tree() utilizes pathspecs to limit the scope of searching.
ensure_full_index() always expands the index, which means it will
always walk all the trees and blobs in the repo without caring if
the user only wants a subset of the content, i.e. using a pathspec.
On the other hand, grep_tree() will only search the contents that
match the pathspec, and thus possibly walking fewer trees.
3) grep_tree() does not construct and copy back a new index, while
ensure_full_index() does. This also saves some time.
----------------
Performance test
- Summary:
p2000 tests demonstrate a ~71% execution time reduction for
`git grep --cached bogus -- "f2/f1/f1/*"` using tree-walking logic.
However, notice that this result varies depending on the pathspec
given. See below "Command used for testing" for more details.
Test HEAD~ HEAD
-------------------------------------------------------
2000.78: git grep ... (full-v3) 0.35 0.39 (≈)
2000.79: git grep ... (full-v4) 0.36 0.30 (≈)
2000.80: git grep ... (sparse-v3) 0.88 0.23 (-73.8%)
2000.81: git grep ... (sparse-v4) 0.83 0.26 (-68.6%)
- Command used for testing:
git grep --cached bogus -- "f2/f1/f1/*"
The reason for specifying a pathspec is that, if we don't specify a
pathspec, then grep_tree() will walk all the trees and blobs to find the
pattern, and the time consumed doing so is not too different from using
the original ensure_full_index() method, which also spends most of the
time walking trees. However, when a pathspec is specified, this latest
logic will only walk the area of trees enclosed by the pathspec, and the
time consumed is reasonably a lot less.
Generally speaking, because the performance gain is acheived by walking
less trees, which are specified by the pathspec, the HEAD time v.s.
HEAD~ time in sparse-v[3|4], should be proportional to
"pathspec enclosed area" v.s. "all area", respectively. Namely, the
wider the <pathspec> is encompassing, the less the performance
difference between HEAD~ and HEAD, and vice versa.
That is, if we don't specify a pathspec, the performance difference [1]
is indistinguishable: both methods walk all the trees and take generally
same amount of time (even with the index construction time included for
ensure_full_index()).
[1] Performance test result without pathspec (hence walking all trees):
Command used:
git grep --cached bogus
Test HEAD~ HEAD
---------------------------------------------------
2000.78: git grep ... (full-v3) 6.17 5.19 (≈)
2000.79: git grep ... (full-v4) 6.19 5.46 (≈)
2000.80: git grep ... (sparse-v3) 6.57 6.44 (≈)
2000.81: git grep ... (sparse-v4) 6.65 6.28 (≈)
--------------------------
NEEDSWORK about submodules
There are a few NEEDSWORKs that belong to improvements beyond this
topic. See the NEEDSWORK in builtin/grep.c::grep_submodule() for
more context. The other two NEEDSWORKs in t1092 are also relative.
Suggested-by: Derrick Stolee <derrickstolee@github.com>
Helped-by: Derrick Stolee <derrickstolee@github.com>
Helped-by: Victoria Dye <vdye@github.com>
Helped-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Shaoxuan Yuan <shaoxuan.yuan02@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
GNU grep deprecated `egrep` and `fgrep` with release 2.5.3 in 2007.
As of release 3.8 in 2022, those commands warn[1] that they are
obsolescent. Now that all the Git test scripts have been scrubbed of
uses of `egrep` and `fgrep`, make `check-non-portable-shell` complain
about them to prevent new instances from creeping back into the project.
[1]: https://lists.gnu.org/archive/html/info-gnu/2022-09/msg00001.html
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* 'main' of github.com:git/git:
list-objects-filter: initialize sub-filter structs
Git 2.38-rc1
Final batch before -rc1
builtin/diagnose.c: don't translate the two mode values
t/Makefile: remove 'test-results' on 'make clean'
gc: don't translate literal commands
Documentation: clean up various typos in technical docs
Documentation: clean up a few misspelled word typos
version: fix builtin linking & documentation
diagnose: add to command-list.txt
Documentation: add ReviewingGuidelines
commit-graph: Fix missing closedir in expire_commit_graphs
diagnose.c: refactor to safely use 'd_type'
help: fix doubled words in explanation for developer interfaces
api docs: link to html version of api-trace2
docs: fix a few recently broken links
reftable: use a pointer for pq_entry param
Fix uninitialized memory access in a recent fix-up that is already
in -rc1.
* jk/list-objects-filter-cleanup:
list-objects-filter: initialize sub-filter structs
Like in all the other credential helpers, the osxkeychain helper
ignores unknown credential lines.
Add a comment (a la the other helpers) to make it clear and explicit
that this is the desired behaviour.
Signed-off-by: Matthew John Cheetham <mjcheetham@outlook.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Contrary to the documentation on credential helpers, as well as the help
text for git-credential-netrc itself, this helper will `die` when
presented with an unknown property/attribute/token.
Correct the behaviour here by skipping and ignoring any tokens that are
unknown. This means all helpers in the tree are consistent and ignore
any unknown credential properties/attributes.
Signed-off-by: Matthew John Cheetham <mjcheetham@outlook.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It is the expectation that credential helpers be liberal in what they
accept and conservative in what they return, to allow for future growth
and evolution of the protocol/interaction.
All of the other helpers (store, cache, osxkeychain, libsecret,
gnome-keyring) except `netrc` currently ignore any credential lines
that are not recognised, whereas the Windows helper (wincred) instead
dies.
Fix the discrepancy and ignore unknown lines in the wincred helper.
Signed-off-by: Matthew John Cheetham <mjcheetham@outlook.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We return an error when trying to rename a remote that has no fetch
refspec:
$ git config --unset-all remote.origin.fetch
$ git remote rename origin foo
fatal: could not unset 'remote.foo.fetch'
To make things even more confusing, we actually _do_ complete the config
modification, via git_config_rename_section(). After that we try to
rewrite the fetch refspec (to say refs/remotes/foo instead of origin).
But our call to git_config_set_multivar() to remove the existing entries
fails, since there aren't any, and it calls die().
We could fix this by using the "gently" form of the config call, and
checking the error code. But there is an even simpler fix: if we know
that there are no refspecs to rewrite, then we can skip that part
entirely.
Reported-by: John A. Leuenhagen <john@zlima12.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We explicitly forbid the combination of "--bare" with "-o", but there
doesn't seem to be any good reason to do so. The original logic came as
part of e6489a1bdf (clone: do not accept more than one -o option.,
2006-01-22), but that commit does not give any reason.
Furthermore, the equivalent combination via config is allowed:
git -c clone.defaultRemoteName=foo clone ...
and works as expected. It may be that this combination was considered
useless, because a bare clone does not set remote.origin.fetch (and
hence there is no refs/remotes/origin hierarchy). But it does set
remote.origin.url, and that name is visible to the user via "git fetch
origin", etc.
Let's allow the options to be used together, and switch the "forbid"
test in t5606 to check that we use the requested name. That test came
much later in 349cff76de (clone: add tests for --template and some
disallowed option pairs, 2020-09-29), and does not offer any logic
beyond "let's test what the code currently does".
Reported-by: John A. Leuenhagen <john@zlima12.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
