Commit Graph

10792 Commits

Author SHA1 Message Date
Ben Peart
65cab33aff fscache: fscache takes an initial size
Update enable_fscache() to take an optional initial size parameter which is
used to initialize the hashmap so that it can avoid having to rehash as
additional entries are added.

Add a separate disable_fscache() macro to make the code clearer and easier
to read.

Signed-off-by: Ben Peart <benpeart@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2022-12-12 15:25:22 +01:00
Ben Peart
a059205cad status: disable and free fscache at the end of the status command
At the end of the status command, disable and free the fscache so that we
don't leak the memory and so that we can dump the fscache statistics.

Signed-off-by: Ben Peart <benpeart@microsoft.com>
2022-12-12 15:25:22 +01:00
Takuto Ikuta
77434e733a checkout.c: enable fscache for checkout again
This is retry of #1419.

I added flush_fscache macro to flush cached stats after disk writing
with tests for regression reported in #1438 and #1442.

git checkout checks each file path in sorted order, so cache flushing does not
make performance worse unless we have large number of modified files in
a directory containing many files.

Using chromium repository, I tested `git checkout .` performance when I
delete 10 files in different directories.
With this patch:
TotalSeconds: 4.307272
TotalSeconds: 4.4863595
TotalSeconds: 4.2975562
Avg: 4.36372923333333

Without this patch:
TotalSeconds: 20.9705431
TotalSeconds: 22.4867685
TotalSeconds: 18.8968292
Avg: 20.7847136

I confirmed this patch passed all tests in t/ with core_fscache=1.

Signed-off-by: Takuto Ikuta <tikuta@chromium.org>
2022-12-12 15:25:22 +01:00
Jeff Hostetler
411e669a67 add: use preload-index and fscache for performance
Teach "add" to use preload-index and fscache features
to improve performance on very large repositories.

During an "add", a call is made to run_diff_files()
which calls check_remove() for each index-entry.  This
calls lstat().  On Windows, the fscache code intercepts
the lstat() calls and builds a private cache using the
FindFirst/FindNext routines, which are much faster.

Somewhat independent of this, is the preload-index code
which distributes some of the start-up costs across
multiple threads.

We need to keep the call to read_cache() before parsing the
pathspecs (and hence cannot use the pathspecs to limit any preload)
because parse_pathspec() is using the index to determine whether a
pathspec is, in fact, in a submodule. If we would not read the index
first, parse_pathspec() would not error out on a path that is inside
a submodule, and t7400-submodule-basic.sh would fail with

	not ok 47 - do not add files from a submodule

We still want the nice preload performance boost, though, so we simply
call read_cache_preload(&pathspecs) after parsing the pathspecs.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2022-12-12 15:25:22 +01:00
Karsten Blees
9530b397f9 add infrastructure for read-only file system level caches
Add a macro to mark code sections that only read from the file system,
along with a config option and documentation.

This facilitates implementation of relatively simple file system level
caches without the need to synchronize with the file system.

Enable read-only sections for 'git status' and preload_index.

Signed-off-by: Karsten Blees <blees@dcon.de>
2022-12-12 15:25:22 +01:00
Johannes Schindelin
8d8dc978d1 Merge pull request #3417 from dscho/initialize-core.symlinks-earlier
init: respect core.symlinks before copying the templates
2022-12-12 15:25:20 +01:00
Johannes Schindelin
7168e2a941 Merge pull request #2974 from derrickstolee/maintenance-and-headless
Include Windows-specific maintenance and headless-git
2022-12-12 15:25:19 +01:00
Johannes Schindelin
3a9686265a init: do parse _all_ core.* settings early
In Git for Windows, `has_symlinks` is set to 0 by default. Therefore, we
need to parse the config setting `core.symlinks` to know if it has been
set to `true`. In `git init`, we must do that before copying the
templates because they might contain symbolic links.

Even if the support for symbolic links on Windows has not made it to
upstream Git yet, we really should make sure that all the `core.*`
settings are parsed before proceeding, as they might very well change
the behavior of `git init` in a way the user intended.

This fixes https://github.com/git-for-windows/git/issues/3414

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2022-12-12 15:25:14 +01:00
Johannes Schindelin
2a1818ca9d git maintenance: avoid console window in scheduled tasks on Windows
We just introduced a helper to avoid showing a console window when the
scheduled task runs `git.exe`. Let's actually use it.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
2022-12-12 15:25:13 +01:00
Johannes Schindelin
f4f0b3c9fb clean: remove mount points when possible
Windows' equivalent to "bind mounts", NTFS junction points, can be
unlinked without affecting the mount target. This is clearly what users
expect to happen when they call `git clean -dfx` in a worktree that
contains NTFS junction points: the junction should be removed, and the
target directory of said junction should be left alone (unless it is
inside the worktree).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2022-12-12 15:25:11 +01:00
Johannes Schindelin
d2fd8bb249 clean: do not traverse mount points
It seems to be not exactly rare on Windows to install NTFS junction
points (the equivalent of "bind mounts" on Linux/Unix) in worktrees,
e.g. to map some development tools into a subdirectory.

In such a scenario, it is pretty horrible if `git clean -dfx` traverses
into the mapped directory and starts to "clean up".

Let's just not do that. Let's make sure before we traverse into a
directory that it is not a mount point (or junction).

This addresses https://github.com/git-for-windows/git/issues/607

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2022-12-12 15:25:11 +01:00
Junio C Hamano
fd8dcbb07c Merge branch 'ab/doc-synopsis-and-cmd-usage'
Doc and message fix.

* ab/doc-synopsis-and-cmd-usage:
  i18n: fix command template placeholder format
2022-11-29 10:41:06 +09:00
Junio C Hamano
041df69edd Merge branch 'ab/fewer-the-index-macros'
Progress on removing 'the_index' convenience wrappers.

* ab/fewer-the-index-macros:
  cocci: apply "pending" index-compatibility to some "builtin/*.c"
  cache.h & test-tool.h: add & use "USE_THE_INDEX_VARIABLE"
  {builtin/*,repository}.c: add & use "USE_THE_INDEX_VARIABLE"
  cocci: apply "pending" index-compatibility to "t/helper/*.c"
  cocci & cache.h: apply variable section of "pending" index-compatibility
  cocci & cache.h: apply a selection of "pending" index-compatibility
  cocci: add a index-compatibility.pending.cocci
  read-cache API & users: make discard_index() return void
  cocci & cache.h: remove rarely used "the_index" compat macros
  builtin/{grep,log}.: don't define "USE_THE_INDEX_COMPATIBILITY_MACROS"
  cache.h: remove unused "the_index" compat macros
2022-11-28 12:13:46 +09:00
Junio C Hamano
7d7ed48dd5 Merge branch 'ew/prune-with-missing-objects-pack'
"git prune" may try to iterate over .git/objects/pack for trash
files to remove in it, and loudly fail when the directory is
missing, which is not necessary.  The command has been taught to
ignore such a failure.

* ew/prune-with-missing-objects-pack:
  prune: quiet ENOENT on missing directories
2022-11-28 12:13:44 +09:00
Jean-Noël Avila
d1ddc4e3f6 i18n: fix command template placeholder format
Signed-off-by: Jean-Noël Avila <jn.avila@free.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-11-27 10:29:44 +09:00
Junio C Hamano
f8828f9125 Merge branch 'ps/receive-use-only-advertised'
"git receive-pack" used to use all the local refs as the boundary for
checking connectivity of the data "git push" sent, but now it uses
only the refs that it advertised to the pusher. In a repository with
the .hideRefs configuration, this reduces the resources needed to
perform the check.
cf. <221028.86bkpw805n.gmgdl@evledraar.gmail.com>
cf. <xmqqr0yrizqm.fsf@gitster.g>

* ps/receive-use-only-advertised:
  receive-pack: only use visible refs for connectivity check
  rev-parse: add `--exclude-hidden=` option
  revision: add new parameter to exclude hidden refs
  revision: introduce struct to handle exclusions
  revision: move together exclusion-related functions
  refs: get rid of global list of hidden refs
  refs: fix memory leak when parsing hideRefs config
2022-11-23 11:22:25 +09:00
Junio C Hamano
173fc54b00 Merge branch 'jt/submodule-on-demand'
Push all submodules recursively with
'--recurse-submodules=on-demand'.

* jt/submodule-on-demand:
  Doc: document push.recurseSubmodules=only
2022-11-23 11:22:25 +09:00
Junio C Hamano
2fe427ecb7 Merge branch 'mg/notes-newline'
Avoid a stray empty newline in the template when creating new notes.

* mg/notes-newline:
  notes: avoid empty line in template
2022-11-23 11:22:25 +09:00
Junio C Hamano
ff84d031a9 Merge branch 'pw/rebase-no-reflog-action'
Avoid setting GIT_REFLOG_ACTION to improve readability of the
sequencer internals.

* pw/rebase-no-reflog-action:
  rebase: stop exporting GIT_REFLOG_ACTION
  sequencer: stop exporting GIT_REFLOG_ACTION
2022-11-23 11:22:24 +09:00
Junio C Hamano
56a64fcdc3 Merge branch 'rp/maintenance-qol'
'git maintenance register' is taught to write configuration to an
arbitrary path, and 'git for-each-repo' is taught to expand tilde
characters in paths.

* rp/maintenance-qol:
  builtin/gc.c: fix use-after-free in maintenance_unregister()
  maintenance --unregister: fix uninit'd data use & -Wdeclaration-after-statement
  maintenance: add option to register in a specific config
  for-each-repo: interpolate repo path arguments
2022-11-23 11:22:24 +09:00
Junio C Hamano
e3d40fb240 Merge branch 'dd/bisect-helper-subcommand'
Fix a regression in the bisect-helper which mistakenly treats
arguments to the command given to 'git bisect run' as arguments to
the helper.

* dd/bisect-helper-subcommand:
  bisect--helper: parse subcommand with OPT_SUBCOMMAND
  bisect--helper: move all subcommands into their own functions
  bisect--helper: remove unused options
2022-11-23 11:22:22 +09:00
Junio C Hamano
1107a3963b Merge branch 'ab/submodule-helper-prep-only'
Preparation to remove git-submodule.sh and replace it with a builtin.

* ab/submodule-helper-prep-only:
  submodule--helper: use OPT_SUBCOMMAND() API
  submodule--helper: drop "update --prefix <pfx>" for "-C <pfx> update"
  submodule--helper: remove --prefix from "absorbgitdirs"
  submodule API & "absorbgitdirs": remove "----recursive" option
  submodule.c: refactor recursive block out of absorb function
  submodule tests: test for a "foreach" blind-spot
  submodule--helper: fix a memory leak in "status"
  submodule tests: add tests for top-level flag output
  submodule--helper: move "config" to a test-tool
2022-11-23 11:22:22 +09:00
Eric Wong
6974765352 prune: quiet ENOENT on missing directories
$GIT_DIR/objects/pack may be removed to save inodes in shared
repositories.  Quiet down prune in cases where either
$GIT_DIR/objects or $GIT_DIR/objects/pack is non-existent,
but emit the system error in other cases to help users diagnose
permissions problems or resource constraints.

Signed-off-by: Eric Wong <e@80x24.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-11-21 15:58:54 +09:00
Ævar Arnfjörð Bjarmason
07047d6829 cocci: apply "pending" index-compatibility to some "builtin/*.c"
Apply "index-compatibility.pending.cocci" rule to "builtin/*", but
exclude those where we conflict with in-flight changes.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-11-21 12:06:14 +09:00
Taylor Blau
26734da056 Merge branch 'jk/branch-delete-detached'
Fix a bug where `git branch -d` did not work on an orphaned HEAD.

* jk/branch-delete-detached:
  branch: gracefully handle '-d' on orphan HEAD
2022-11-18 18:44:00 -05:00
Taylor Blau
a92fce4c50 Merge branch 'vd/skip-cache-tree-update'
Avoid calling 'cache_tree_update()' when doing so would be redundant.

* vd/skip-cache-tree-update:
  rebase: use 'skip_cache_tree_update' option
  read-tree: use 'skip_cache_tree_update' option
  reset: use 'skip_cache_tree_update' option
  unpack-trees: add 'skip_cache_tree_update' option
  cache-tree: add perf test comparing update and prime
2022-11-18 18:43:56 -05:00
Taylor Blau
ad9096881d Merge branch 'tb/repack-expire-to'
"git repack" learns to send cruft objects out of the way into
packfiles outside the repository.

* tb/repack-expire-to:
  builtin/repack.c: implement `--expire-to` for storing pruned objects
  builtin/repack.c: write cruft packs to arbitrary locations
  builtin/repack.c: pass "cruft_expiration" to `write_cruft_pack`
  builtin/repack.c: pass "out" to `prepare_pack_objects`
2022-11-18 18:43:09 -05:00
Patrick Steinhardt
bcec6780b2 receive-pack: only use visible refs for connectivity check
When serving a push, git-receive-pack(1) needs to verify that the
packfile sent by the client contains all objects that are required by
the updated references. This connectivity check works by marking all
preexisting references as uninteresting and using the new reference tips
as starting point for a graph walk.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-17 16:22:52 -05:00
Patrick Steinhardt
9b67eb6fbe refs: get rid of global list of hidden refs
We're about to add a new argument to git-rev-list(1) that allows it to
add all references that are visible when taking `transfer.hideRefs` et
al into account. This will require us to potentially parse multiple sets
of hidden refs, which is not easily possible right now as there is only
a single, global instance of the list of parsed hidden refs.

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

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

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

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

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

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

Tests pass unchanged after this code change.

Signed-off-by: Michael J Gruber <git@grubix.eu>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-16 14:57:32 -05:00
Taylor Blau
03744bbdc4 builtin/gc.c: fix use-after-free in maintenance_unregister()
While trying to fix a move based on an uninitialized value (along with a
declaration after the first statement), be0fd57228
(maintenance --unregister: fix uninit'd data use &
-Wdeclaration-after-statement, 2022-11-15) unintentionally introduced a
use-after-free.

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

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

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

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

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

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

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

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

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

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

Signed-off-by: Ronan Pigott <ronan@rjp.ie>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-14 22:39:25 -05:00
Jonathan Tan
e62f779ae6 Doc: document push.recurseSubmodules=only
Git learned pushing submodules without pushing the superproject by
the user specifying --recurse-submodules=only through 6c656c3fe4
("submodules: add RECURSE_SUBMODULES_ONLY value", 2016-12-20) and
225e8bf778 ("push: add option to push only submodules", 2016-12-20).
For users who use this feature regularly, it is desirable to have an
equivalent configuration.

It turns out that such a configuration (push.recurseSubmodules=only) is
already supported, even though it is neither documented nor mentioned
in the commit messages, due to the way the --recurse-submodules=only
feature was implemented (a function used to parse --recurse-submodules
was updated to support "only", but that same function is used to parse
push.recurseSubmodules too). What is left is to document it and test it,
which is what this commit does.

There is a possible point of confusion when recursing into a submodule
that itself has the push.recurseSubmodules=only configuration, because
if a repository has only its submodules pushed and not itself, its
superproject can never be pushed. Therefore, treat such configurations
as being "on-demand", and print a warning message.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-14 16:55:50 -05:00
Đoàn Trần Công Danh
e9011b6092 bisect--helper: parse subcommand with OPT_SUBCOMMAND
As of it is, we're parsing subcommand with OPT_CMDMODE, which will
continue to parse more options even if the command has been found.

When we're running "git bisect run" with a command that expecting
a "--log" or "--no-log" arguments, or one of those "--bisect-..."
arguments, bisect--helper may mistakenly think those options are
bisect--helper's option.

We may fix those problems by passing "--" when calling from
git-bisect.sh, and skip that "--" in bisect--helper. However, it may
interfere with user's "--".

Let's parse subcommand with OPT_SUBCOMMAND since that API was born for
this specific use-case.

Reported-by: Lukáš Doktor <ldoktor@redhat.com>
Signed-off-by: Đoàn Trần Công Danh <congdanhqx@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-11 17:04:57 -05:00
Đoàn Trần Công Danh
464ce0aba8 bisect--helper: move all subcommands into their own functions
In a later change, we will use OPT_SUBCOMMAND to parse sub-commands to
avoid consuming non-option opts.

Since OPT_SUBCOMMAND needs a function pointer to operate,
let's move it now.

Signed-off-by: Đoàn Trần Công Danh <congdanhqx@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-11 17:04:54 -05:00
Đoàn Trần Công Danh
58786d73ba bisect--helper: remove unused options
'git-bisect.sh' used to have a 'bisect_next_check' to check if we have
both good/bad, old/new terms set or not.  In commit 129a6cf344
(bisect--helper: `bisect_next_check` shell function in C, 2019-01-02),
a subcommand for bisect--helper was introduced to port the check to C.
Since d1bbbe45df (bisect--helper: reimplement `bisect_run` shell
function in C, 2021-09-13), all users of 'bisect_next_check' was
re-implemented in C, this subcommand was no longer used but we forgot
to remove '--bisect-next-check'.

'git-bisect.sh' also used to have a 'bisect_write' function, whose
third positional parameter was a "nolog" flag.  This flag was only used
when 'bisect_start' invoked 'bisect_write' to write the starting good
and bad revisions.  Then 0f30233a11 (bisect--helper: `bisect_write`
shell function in C, 2019-01-02) ported it to C as a command mode of
'bisect--helper', which (incorrectly) added the '--no-log' option,
and convert the only place ('bisect_start') that call 'bisect_write'
with 'nolog' to 'git bisect--helper --bisect-write' with 'nolog'
instead of '--no-log', since 'bisect--helper' has command modes not
subcommands, all other command modes see and handle that option as well.
This bogus state didn't last long, however, because in the same patch
series 06f5608c14 (bisect--helper: `bisect_start` shell function
partially in C, 2019-01-02) the C reimplementation of bisect_start()
started calling the bisect_write() C function, this time with the
right 'nolog' function parameter. From then on there was no need for
the '--no-log' option in 'bisect--helper'. Eventually all bisect
subcommands were ported to C as 'bisect--helper' command modes, each
calling the bisect_write() C function instead, but when the
'--bisect-write' command mode was removed in 68efed8c8a
(bisect--helper: retire `--bisect-write` subcommand, 2021-02-03) it
forgot to remove that '--no-log' option.
'--no-log' option had never been used and it's unused now.

Let's remove --bisect-next-check and --no-log from option parsing.

Signed-off-by: Đoàn Trần Công Danh <congdanhqx@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-11 17:04:52 -05:00
Victoria Dye
dc5d40f5bc read-tree: use 'skip_cache_tree_update' option
When running 'read-tree' with a single tree and no prefix,
'prime_cache_tree()' is called after the tree is unpacked. In that
situation, skip a redundant call to 'cache_tree_update()' in
'unpack_trees()' by enabling the 'skip_cache_tree_update' unpack option.

Removing the redundant cache tree update provides a substantial performance
improvement to 'git read-tree <tree-ish>', as shown by a test added to
'p0006-read-tree-checkout.sh':

Test                          before            after
----------------------------------------------------------------------
read-tree br_ballast_plus_1   3.94(1.80+1.57)   3.00(1.14+1.28) -23.9%

Note that the 'read-tree' in 't1022-read-tree-partial-clone.sh' is updated
to read two trees, rather than one. The test was first introduced in
d3da223f22 (cache-tree: prefetch in partial clone read-tree, 2021-07-23) to
exercise the 'cache_tree_update()' code path, as used in 'git merge'. Since
this patch drops the call to 'cache_tree_update()' in single-tree 'git
read-tree', change the test to use the two-tree variant so that
'cache_tree_update()' is called as intended.

Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-10 21:49:34 -05:00
Victoria Dye
0e47bca0f7 reset: use 'skip_cache_tree_update' option
Enable the 'skip_cache_tree_update' option in the variants that call
'prime_cache_tree()' after 'unpack_trees()' (specifically, 'git reset
--mixed' and 'git reset --hard'). This avoids redundantly rebuilding the
cache tree in both 'cache_tree_update()' at the end of 'unpack_trees()' and
in 'prime_cache_tree()', resulting in a small (but consistent) performance
improvement. From the newly-added 'p7102-reset.sh' test:

Test                         before            after
--------------------------------------------------------------------
7102.1: reset --hard (...)   2.11(0.40+1.54)   1.97(0.38+1.47) -6.6%

Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-10 21:49:34 -05:00
Jeff King
eb20e63f5a branch: gracefully handle '-d' on orphan HEAD
When deleting a branch, "git branch -d" has a safety check that ensures
the branch is merged to its upstream (if any), or to HEAD. To do that,
naturally we try to resolve HEAD to a commit object. If we're on an
orphan branch (i.e., HEAD points to a branch that does not yet exist),
that will fail, and we'll bail with an error:

  $ git branch -d to-delete
  fatal: Couldn't look up commit object for HEAD

This usually isn't that big of a deal. The deletion would fail anyway,
since the branch isn't merged to HEAD, and you'd need to use "-D" (or
"-f"). And doing so skips the HEAD resolution, courtesy of 67affd5173
(git-branch -D: make it work even when on a yet-to-be-born branch,
2006-11-24).

But there are still two problems:

  1. The error message isn't very helpful. We should give the usual "not
     fully merged" message, which points the user at "branch -D". That
     was a problem even back in 67affd5173.

  2. Even without a HEAD, these days it's still possible for the
     deletion to succeed. After 67affd5173, commit 99c419c915 (branch
     -d: base the "already-merged" safety on the branch it merges with,
     2009-12-29) made it OK to delete a branch if it is merged to its
     upstream.

We can fix both by removing the die() in delete_branches() completely,
leaving head_rev NULL in this case. It's tempting to stop there, as it
appears at first glance that the rest of the code does the right thing
with a NULL. But sadly, it's not quite true.

We end up feeding the NULL to repo_is_descendant_of(). In the
traditional code path there, we call repo_in_merge_bases_many(). It
feeds the NULL to repo_parse_commit(), which is smart enough to return
an error, and we immediately return "no, it's not a descendant".

But there's an alternate code path: if we have a commit graph with
generation numbers, we end up in can_all_from_reach(), which does
eventually try to set a flag on the NULL commit and segfaults.

So instead, we'll teach the local branch_merged() helper to treat a NULL
as "not merged". This would be a little more elegant in in_merge_bases()
itself, but that function is called in a lot of places, and it's not
clear that quietly returning "not merged" is the right thing everywhere
(I'd expect in many cases, feeding a NULL is a sign of a bug).

There are four tests here:

  a. The first one confirms that deletion succeeds with an orphaned HEAD
     when the branch is merged to its upstream. This is case (2) above.

  b. Same, but with commit graphs enabled. Even if it is merged to
     upstream, we still check head_rev so that we can say "deleting
     because it's merged to upstream, even though it's not merged to
     HEAD". Without the second hunk in branch_merged(), this test would
     segfault in can_all_from_reach().

  c. The third one confirms that we correctly say "not merged to HEAD"
     when we can't resolve HEAD, and reject the deletion.

  d. Same, but with commit graphs enabled. Without the first hunk in
     branch_merged(), this one would segfault.

Reported-by: Martin von Zweigbergk <martinvonz@google.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-11-10 21:42:45 -05:00