Commit graph

10513 commits

Author SHA1 Message Date
Elijah Newren 8f240b8bbb merge: do not abort early if one strategy fails to handle the merge
builtin/merge is setup to allow multiple strategies to be specified,
and it will find the "best" result and use it.  This is defeated if
some of the merge strategies abort early when they cannot handle the
merge.  Fix the logic that calls recursive and ort to not do such an
early abort, but instead return "2" or "unhandled" so that the next
strategy can try to handle the merge.

Coming up with a testcase for this is somewhat difficult, since
recursive and ort both handle nearly any two-headed merge (there is
a separate code path that checks for non-two-headed merges and
already returns "2" for them).  So use a somewhat synthetic testcase
of having the index not match HEAD before the merge starts, since all
merge strategies will abort for that.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-22 21:45:23 -07:00
Elijah Newren e4cdfe84a0 merge: abort if index does not match HEAD for trivial merges
As noted in the last commit and the links therein (especially commit
9822175d2b ("Ensure index matches head before invoking merge machinery,
round N", 2019-08-17), we have had a very long history of problems with
failing to enforce the requirement that index matches HEAD when starting
a merge.

The "trivial merge" logic in builtin/merge.c is yet another such case
we previously missed.  Add a check for it to ensure it aborts if the
index does not match HEAD, and add a testcase where this fix is needed.

Note that the fix here would also incidentally be an alternative fix
for the testcase added in the last patch, but the fix in the last patch
is still needed when multiple merge strategies are in use, so tweak the
testcase from the previous commit so that it continues to exercise the
codepath added in the last commit.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-22 21:45:23 -07:00
Taylor Blau db9d67f2e9 builtin/cat-file.c: support NUL-delimited input with -z
When callers are using `cat-file` via one of the stdin-driven `--batch`
modes, all input is newline-delimited. This presents a problem when
callers wish to ask about, e.g. tree-entries that have a newline
character present in their filename.

To support this niche scenario, introduce a new `-z` mode to the
`--batch`, `--batch-check`, and `--batch-command` suite of options that
instructs `cat-file` to treat its input as NUL-delimited, allowing the
individual commands themselves to have newlines present.

The refactoring here is slightly unfortunate, since we turn loops like:

    while (strbuf_getline(&buf, stdin) != EOF)

into:

    while (1) {
        int ret;
        if (opt->nul_terminated)
            ret = strbuf_getline_nul(&input, stdin);
        else
            ret = strbuf_getline(&input, stdin);

        if (ret == EOF)
            break;
    }

It's tempting to think that we could use `strbuf_getwholeline()` and
specify either `\n` or `\0` as the terminating character. But for input
on platforms that include a CR character preceeding the LF, this
wouldn't quite be the same, since `strbuf_getline(...)` will trim any
trailing CR, while `strbuf_getwholeline(&buf, stdin, '\n')` will not.

In the future, we could clean this up further by introducing a variant
of `strbuf_getwholeline()` that addresses the aforementioned gap, but
that approach felt too heavy-handed for this pair of uses.

Some tests are added in t1006 to ensure that `cat-file` produces the
same output in `--batch`, `--batch-check`, and `--batch-command` modes
with and without the new `-z` option.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-22 21:42:06 -07:00
Junio C Hamano dd7c820d9e Merge branch 'js/shortlog-sort-stably'
"git shortlog -n" relied on the underlying qsort() to be stable,
which shouldn't have.  Fixed.

* js/shortlog-sort-stably:
  shortlog: use a stable sort
2022-07-22 15:04:02 -07:00
Junio C Hamano 1e11fab59c builtin/remote.c: use the right kind of STRING_LIST_INIT
Since 4a4b4cda (builtin-remote: Make "remote -v" display push urls,
2009-06-13), the string_list that was initialized with 0 in its
strdup_string member is immediately made to strdup its key strings
by flipping the strdup_string member to true.  When 183113a5
(string_list: Add STRING_LIST_INIT macro and make use of it.,
2010-07-04) has introduced STRING_LIST_INIT macros, it mechanically
replaced the initialization to STRING_LIST_INIT_NODUP.

Instead, just use the other initialization macro to make it strdup
the key from the beginning.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-20 21:46:21 -07:00
Junio C Hamano 7c683389d6 Merge branch 'jk/diff-files-cleanup-fix'
An earlier attempt to plug leaks placed a clean-up label to jump to
at a bogus place, which as been corrected.

* jk/diff-files-cleanup-fix:
  diff-files: move misplaced cleanup label
2022-07-19 16:40:18 -07:00
Junio C Hamano cf92cb29e9 Merge branch 'jk/clone-unborn-confusion'
"git clone" from a repository with some ref whose HEAD is unborn
did not set the HEAD in the resulting repository correctly, which
has been corrected.

* jk/clone-unborn-confusion:
  clone: move unborn head creation to update_head()
  clone: use remote branch if it matches default HEAD
  clone: propagate empty remote HEAD even with other branches
  clone: drop extra newline from warning message
2022-07-19 16:40:17 -07:00
Junio C Hamano 418aef9055 Merge branch 'jc/resolve-undo'
The resolve-undo information in the index was not protected against
GC, which has been corrected.

* jc/resolve-undo:
  fsck: do not dereference NULL while checking resolve-undo data
  revision: mark blobs needed for resolve-undo as reachable
2022-07-19 16:40:16 -07:00
Derrick Stolee 3113fedaeb rebase: add rebase.updateRefs config option
The previous change added the --update-refs command-line option.  For
users who always want this mode, create the rebase.updateRefs config
option which behaves the same way as rebase.autoSquash does with the
--autosquash option.

Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-19 12:49:04 -07:00
Derrick Stolee 900b50c242 rebase: add --update-refs option
When working on a large feature, it can be helpful to break that feature
into multiple smaller parts that become reviewed in sequence. During
development or during review, a change to one part of the feature could
affect multiple of these parts. An interactive rebase can help adjust
the multi-part "story" of the branch.

However, if there are branches tracking the different parts of the
feature, then rebasing the entire list of commits can create commits not
reachable from those "sub branches". It can take a manual step to update
those branches.

Add a new --update-refs option to 'git rebase -i' that adds 'update-ref
<ref>' steps to the todo file whenever a commit that is being rebased is
decorated with that <ref>. At the very end, the rebase process updates
all of the listed refs to the values stored during the rebase operation.

Be sure to iterate after any squashing or fixups are placed. Update the
branch only after those squashes and fixups are complete. This allows a
--fixup commit at the tip of the feature to apply correctly to the sub
branch, even if it is fixing up the most-recent commit in that part.

This change update the documentation and builtin to accept the
--update-refs option as well as updating the todo file with the
'update-ref' commands. Tests are added to ensure that these todo
commands are added in the correct locations.

This change does _not_ include the actual behavior of tracking the
updated refs and writing the new ref values at the end of the rebase
process. That is deferred to a later change.

Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-19 12:49:04 -07:00
Junio C Hamano afbe62d84c Merge branch 'sg/multi-pack-index-parse-options-fix'
The way "git multi-pack" uses parse-options API has been improved.

* sg/multi-pack-index-parse-options-fix:
  multi-pack-index: simplify handling of unknown --options
2022-07-18 13:31:58 -07:00
Junio C Hamano 7f8d098b1b Merge branch 'ab/cocci-unused'
Add Coccinelle rules to detect the pattern of initializing and then
finalizing a structure without using it in between at all, which
happens after code restructuring and the compilers fail to
recognize as an unused variable.

* ab/cocci-unused:
  cocci: generalize "unused" rule to cover more than "strbuf"
  cocci: add and apply a rule to find "unused" strbufs
  cocci: have "coccicheck{,-pending}" depend on "coccicheck-test"
  cocci: add a "coccicheck-test" target and test *.cocci rules
  Makefile & .gitignore: ignore & clean "git.res", not "*.res"
  Makefile: remove mandatory "spatch" arguments from SPATCH_FLAGS
2022-07-18 13:31:57 -07:00
Junio C Hamano 6d003858e5 Merge branch 'gc/submodule-use-super-prefix'
Another step to rewrite more parts of "git submodule" in C.

* gc/submodule-use-super-prefix:
  submodule--helper: remove display path helper
  submodule--helper update: use --super-prefix
  submodule--helper: remove unused SUPPORT_SUPER_PREFIX flags
  submodule--helper: use correct display path helper
  submodule--helper: don't recreate recursive prefix
  submodule--helper update: use display path helper
  submodule--helper tests: add missing "display path" coverage
2022-07-18 13:31:56 -07:00
Junio C Hamano 44357f64f6 Merge branch 'ab/leakfix'
Plug various memory leaks.

* ab/leakfix:
  pull: fix a "struct oid_array" memory leak
  cat-file: fix a common "struct object_context" memory leak
  gc: fix a memory leak
  checkout: avoid "struct unpack_trees_options" leak
  merge-file: fix memory leaks on error path
  merge-file: refactor for subsequent memory leak fix
  cat-file: fix a memory leak in --batch-command mode
  revert: free "struct replay_opts" members
  submodule.c: free() memory from xgetcwd()
  clone: fix memory leak in wanted_peer_refs()
  check-ref-format: fix trivial memory leak
2022-07-18 13:31:54 -07:00
Junio C Hamano f01315ef7d Merge branch 'jc/builtin-mv-move-array'
Apply Coccinelle rule to turn raw memmove() into MOVE_ARRAY() cpp
macro, which would improve maintainability and readability.

* jc/builtin-mv-move-array:
  builtin/mv.c: use the MOVE_ARRAY() macro instead of memmove()
2022-07-18 13:31:53 -07:00
Siddharth Asthana ec031da9f9 cat-file: add mailmap support
git-cat-file is used by tools like GitLab to get commit tag contents
that are then displayed to users. This content which has author,
committer or tagger information, could benefit from passing through the
mailmap mechanism before being sent or displayed.

This patch adds --[no-]use-mailmap command line option to the git
cat-file command. It also adds --[no-]mailmap option as an alias to
--[no-]use-mailmap.

This patch also introduces new test cases to test the mailmap mechanism in
git cat-file command.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: John Cai <johncai86@gmail.com>
Helped-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Helped-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Siddharth Asthana <siddharthasthana31@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-18 12:55:53 -07:00
Junio C Hamano 361cbe6d6d Merge branch 'ab/submodule-cleanup'
Further preparation to turn git-submodule.sh into a builtin.

* ab/submodule-cleanup:
  git-sh-setup.sh: remove "say" function, change last users
  git-submodule.sh: use "$quiet", not "$GIT_QUIET"
  submodule--helper: eliminate internal "--update" option
  submodule--helper: understand --checkout, --merge and --rebase synonyms
  submodule--helper: report "submodule" as our name in some "-h" output
  submodule--helper: rename "absorb-git-dirs" to "absorbgitdirs"
  submodule update: remove "-v" option
  submodule--helper: have --require-init imply --init
  git-submodule.sh: remove unused top-level "--branch" argument
  git-submodule.sh: make the "$cached" variable a boolean
  git-submodule.sh: remove unused $prefix variable
  git-submodule.sh: remove unused sanitize_submodule_env()
2022-07-14 15:04:00 -07:00
Junio C Hamano 0455aad1e3 Merge branch 'sy/mv-out-of-cone'
"git mv A B" in a sparsely populated working tree can be asked to
move a path between directories that are "in cone" (i.e. expected
to be materialized in the working tree) and "out of cone"
(i.e. expected to be hidden).  The handling of such cases has been
improved.

* sy/mv-out-of-cone:
  mv: add check_dir_in_index() and solve general dir check issue
  mv: use flags mode for update_mode
  mv: check if <destination> exists in index to handle overwriting
  mv: check if out-of-cone file exists in index with SKIP_WORKTREE bit
  mv: decouple if/else-if checks using goto
  mv: update sparsity after moving from out-of-cone to in-cone
  t1092: mv directory from out-of-cone to in-cone
  t7002: add tests for moving out-of-cone file/directory
2022-07-14 15:04:00 -07:00
Junio C Hamano 73b9ef6ab1 Merge branch 'hx/unpack-streaming'
Allow large objects read from a packstream to be streamed into a
loose object file straight, without having to keep it in-core as a
whole.

* hx/unpack-streaming:
  unpack-objects: use stream_loose_object() to unpack large objects
  core doc: modernize core.bigFileThreshold documentation
  object-file.c: add "stream_loose_object()" to handle large object
  object-file.c: factor out deflate part of write_loose_object()
  object-file.c: refactor write_loose_object() to several steps
  unpack-objects: low memory footprint for get_data() in dry_run mode
2022-07-14 15:03:59 -07:00
Junio C Hamano be733e1200 Merge branch 'en/merge-tree'
"git merge-tree" learned a new mode where it takes two commits and
computes a tree that would result in the merge commit, if the
histories leading to these two commits were to be merged.

* en/merge-tree:
  git-merge-tree.txt: add a section on potentional usage mistakes
  merge-tree: add a --allow-unrelated-histories flag
  merge-tree: allow `ls-files -u` style info to be NUL terminated
  merge-ort: optionally produce machine-readable output
  merge-ort: store more specific conflict information
  merge-ort: make `path_messages` a strmap to a string_list
  merge-ort: store messages in a list, not in a single strbuf
  merge-tree: provide easy access to `ls-files -u` style info
  merge-tree: provide a list of which files have conflicts
  merge-ort: remove command-line-centric submodule message from merge-ort
  merge-ort: provide a merge_get_conflicted_files() helper function
  merge-tree: support including merge messages in output
  merge-ort: split out a separate display_update_messages() function
  merge-tree: implement real merges
  merge-tree: add option parsing and initial shell for real merge function
  merge-tree: move logic for existing merge into new function
  merge-tree: rename merge_trees() to trivial_merge_trees()
2022-07-14 15:03:59 -07:00
Johannes Schindelin df534dcbaa shortlog: use a stable sort
When sorting the output of `git shortlog` by count, a list of authors in
alphabetical order is then sorted by contribution count. Obviously, the
idea is to maintain the alphabetical order for items with identical
contribution count.

At the moment, this job is performed by `qsort()`. As that function is
not guaranteed to implement a stable sort algorithm, this can lead to
inconsistent and/or surprising behavior: items with identical
contribution count could lose their alphabetical sub-order.

The `qsort()` in MS Visual C's runtime does _not_ implement a stable
sort algorithm, and under certain circumstances this even causes a test
failure in t4201.21 "shortlog can match multiple groups", where two
authors both are listed with 2 contributions, and are listed in inverse
alphabetical order.

Let's instead use the stable sort provided by `git_stable_qsort()` to
avoid this inconsistency.

This is a companion to 2049b8dc65 (diffcore_rename(): use a stable sort,
2019-09-30).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-14 11:24:11 -07:00
Matheus Tavares 611c7785e8 checkout: fix two bugs on the final count of updated entries
At the end of `git checkout <pathspec>`, we get a message informing how
many entries were updated in the working tree. However, this number can
be inaccurate for two reasons:

1) Delayed entries currently get counted twice.
2) Failed entries are included in the count.

The first problem happens because the counter is first incremented
before inserting the entry in the delayed checkout queue, and once again
when finish_delayed_checkout() calls checkout_entry(). And the second
happens because the counter is incremented too early in
checkout_entry(), before the entry was in fact checked out. Fix that by
moving the count increment further down in the call stack and removing
the duplicate increment on delayed entries. Note that we have to keep
a per-entry reference for the counter (both on parallel checkout and
delayed checkout) because not all entries are always accumulated at the
same counter. See checkout_worktree(), at builtin/checkout.c for an
example.

Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-14 10:19:28 -07:00
Junio C Hamano 8c4f65e0bf Merge branch 'cl/grep-max-count'
"git grep -m<max-hits>" is a way to limit the hits shown per file.

* cl/grep-max-count:
  grep: add --max-count command line option
2022-07-13 14:54:55 -07:00
Junio C Hamano 33f448b5fc Merge branch 'jk/remote-show-with-negative-refspecs'
"git remote show [-n] frotz" now pays attention to negative
pathspec.

* jk/remote-show-with-negative-refspecs:
  remote: handle negative refspecs in git remote show
2022-07-13 14:54:54 -07:00
Junio C Hamano 6fccbdaa51 Merge branch 'ro/mktree-allow-missing-fix'
"git mktree --missing" lazily fetched objects that are missing from
the local object store, which was totally unnecessary for the purpose
of creating the tree object(s) from its input.

* ro/mktree-allow-missing-fix:
  mktree: do not check type of remote objects
2022-07-13 14:54:53 -07:00
Junio C Hamano 7fefa1b68e Merge branch 'ds/branch-checked-out' into ds/rebase-update-ref
* ds/branch-checked-out:
  branch: drop unused worktrees variable
  fetch: stop passing around unused worktrees variable
  branch: fix branch_checked_out() leaks
  branch: use branch_checked_out() when deleting refs
  fetch: use new branch_checked_out() and add tests
  branch: check for bisects and rebases
  branch: add branch_checked_out() helper
2022-07-12 08:38:42 -07:00
Jeff King 04393ae7f7 diff-files: move misplaced cleanup label
Commit 0139c58ab9 (revisions API users: add "goto cleanup" for
release_revisions(), 2022-04-13) converted an early return in
cmd_diff_files() into a goto. But it put the cleanup label too early: if
read_cache_preload() returns an error, we'll set result to "-1", but
then jump to calling run_diff_files(), overwriting our result.

We should jump past the call to run_diff_files(). Likewise, we should go
past diff_result_code(), which is expecting to see a code from an actual
diff, not a negative error code.

In practice, I suspect this bug cannot actually be triggered, because
read_cache_preload() does not seem to ever return an error. Its return
value (eventually) comes from do_read_index(), which gives the number of
cache entries found, and calls die() on error. Still, it makes sense to
fix the inadvertent change from 0139c58ab9 first, and we can look into
the overall error handling of read_cache() separately (which is present
in many other callsites).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-12 07:17:28 -07:00
Junio C Hamano e0ad13977a fsck: do not dereference NULL while checking resolve-undo data
When we found an invalid object recorded in the resolve-undo data,
we would have ended up dereferencing NULL while fsck.  Reporting the
problem and going on to the next object is the right thing to do
here.

Noticed by SZEDER Gábor.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-11 16:26:33 -07:00
Junio C Hamano c2d01098fb Merge branch 'ds/branch-checked-out'
Introduce a helper to see if a branch is already being worked on
(hence should not be newly checked out in a working tree), which
performs much better than the existing find_shared_symref() to
replace many uses of the latter.

* ds/branch-checked-out:
  branch: drop unused worktrees variable
  fetch: stop passing around unused worktrees variable
  branch: fix branch_checked_out() leaks
  branch: use branch_checked_out() when deleting refs
  fetch: use new branch_checked_out() and add tests
  branch: check for bisects and rebases
  branch: add branch_checked_out() helper
2022-07-11 15:38:51 -07:00
Jeff King daf7898abb clone: move unborn head creation to update_head()
Prior to 4f37d45706 (clone: respect remote unborn HEAD, 2021-02-05),
creation of the local HEAD was always done in update_head(). That commit
added code to handle an unborn head in an empty repository, and just did
all symref creation and config setup there.

This makes the code flow a little bit confusing, especially as new
corner cases have been covered (like the previous commit to match our
default branch name to a non-HEAD remote branch).

Let's move the creation of the unborn symref into update_head(). This
matches the other HEAD-creation cases, and now the logic is consistently
separated: the main cmd_clone() function only examines the situation and
sets variables based on what it finds, and update_head() actually
performs the update.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-11 13:32:37 -07:00
SZEDER Gábor cc74afb83f multi-pack-index: simplify handling of unknown --options
Although parse_options() can handle unknown --options just fine, none
of 'git multi-pack-index's subcommands rely on it, but do it on their
own: they invoke parse_options() with the PARSE_OPT_KEEP_UNKNOWN flag,
then check whether there are any unparsed arguments left, and print
usage and quit if necessary.

Drop that PARSE_OPT_KEEP_UNKNOWN flag to let parse_options() handle
unknown options instead, which has the additional benefit that it
prints not only the usage but an "error: unknown option `foo'" message
as well.

Do leave the unparsed arguments check to catch any unexpected
non-option arguments, though, e.g. 'git multi-pack-index write foo'.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-10 14:53:48 -07:00
Junio C Hamano eee227ad8e builtin/mv.c: use the MOVE_ARRAY() macro instead of memmove()
The variables 'source', 'destination', and 'submodule_gitfile' are
all of type "const char **", and an element of such an array is of
"type const char *", but these memmove() calls were written as if
these variables are of type "char **".

Once these memmove() calls are fixed to use the correct type to
compute the number of bytes to be moved, e.g.

-      memmove(source + i, source + i + 1, n * sizeof(char *));
+      memmove(source + i, source + i + 1, n * sizeof(const char *));

existing contrib/coccinelle/array.cocci rules can recognize them as
candidates for turning into MOVE_ARRAY().

While at it, use CALLOC_ARRAY() instead of xcalloc() to allocate the
modes[] array that is involved in the change.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-09 18:38:57 -07:00
Jeff King cc8fcd1e1a clone: use remote branch if it matches default HEAD
Usually clone tries to use the same local HEAD as the remote (unless the
user has given --branch explicitly). Even if the remote HEAD is detached
or unborn, we can detect those situations with modern versions of Git.
If the remote is too old to support the "unborn" extension (or it has
been disabled via config), then we can't know the name of the remote's
unborn HEAD, and we fall back whatever the local default branch name is
configured to be.

But that leads to one weird corner case. It's rare because it needs a
number of factors:

  - the remote has an unborn HEAD

  - the remote is too old to support "unborn", or has disabled it

  - the remote has another branch "foo"

  - the local default branch name is "foo"

In that case you end up with a local clone on an unborn "foo" branch,
disconnected completely from the remote's "foo". This is rare in
practice, but the result is quite confusing.

When choosing "foo", we can double check whether the remote has such a
name, and if so, start our local "foo" at the same spot, rather than
making it unborn.

Note that this causes a test failure in t5605, which is cloning from a
bundle that doesn't contain HEAD (so it behaves like a remote that
doesn't support "unborn"), but has a single "main" branch. That test
expects that we end up in the weird "unborn main" case, where we don't
actually check out the remote branch of the same name. Even though we
have to update the test, this seems like an argument in favor of this
patch: checking out main is what I'd expect from such a bundle.

So this patch updates the test for the new behavior and adds an adjacent
one that checks what the original was going for: if there's no HEAD and
the bundle _doesn't_ have a branch that matches our local default name,
then we end up with nothing checked out.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-07 20:57:54 -07:00
Jeff King 3d8314f8d1 clone: propagate empty remote HEAD even with other branches
Unless "--branch" was given, clone generally tries to match the local
HEAD to the remote one. For most repositories, this is easy: the remote
tells us which branch HEAD was pointing to, and we call our local
checkout() function on that branch.

When cloning an empty repository, it's a little more tricky: we have
special code that checks the transport's "unborn" extension, or falls back
to our local idea of what the default branch should be. In either case,
we point the new HEAD to that, and set up the branch.* config.

But that leaves one case unhandled: when the remote repository _isn't_
empty, but its HEAD is unborn. The checkout() function is smart enough
to realize we didn't fetch the remote HEAD and it bails with a warning.
But we'll have ignored any information the remote gave us via the unborn
extension. This leads to nonsense outcomes:

  - If the remote has its HEAD pointing to an unborn "foo" and contains
    another branch "bar", cloning will get branch "bar" but leave the
    local HEAD pointing at "master" (or whatever our local default is),
    which is useless. The project does not use "master" as a branch.

  - Worse, if the other branch "bar" is instead called "master" (but
    again, the remote HEAD is not pointing to it), then we end up with a
    local unborn branch "master", which is not connected to the remote
    "master" (it shares no history, and there's no branch.* config).

Instead, we should try to use the remote's HEAD, even if its unborn, to
be consistent with the other cases.

The reason this case was missed is that cmd_clone() handles empty and
non-empty repositories on two different sides of a conditional:

  if (we have any refs) {
      fetch refs;
      check for --branch;
      otherwise, try to point our head at remote head;
      otherwise, our head is NULL;
  } else {
      check for --branch;
      otherwise, try to use "unborn" extension;
      otherwise, fall back to our default name name;
  }

So the smallest change would be to repeat the "unborn" logic at the end
of the first block. But we can note some other overlaps and
inconsistencies:

  - both sides have to handle --branch (though note that it's always an
    error for the empty repo case, since an empty repo by definition
    does not have a matching branch)

  - the fall back to the default name is much more explicit in the
    empty-repo case. The non-empty case eventually ends up bailing
    from checkout() with a warning, which produces a similar result, but
    fails to set up the branch config we do in the empty case.

So let's pull the HEAD setup out of this conditional entirely. This
de-duplicates some of the code and the result is easy to follow, because
helper functions like find_ref_by_name() do the right thing even in the
empty-repo case (i.e., by returning NULL).

There are two subtleties:

  - for a remote with a detached HEAD, it will advertise an oid for HEAD
    (which we store in our "remote_head" variable), but we won't find a
    matching refname (so our "remote_head_points_at" is NULL). In this
    case we make a local detached HEAD to match. Right now this happens
    implicitly by reaching update_head() with a non-NULL remote_head
    (since we skip all of the unborn-fallback). We'll now need to
    account for it explicitly before doing the fallback.

  - for an empty repo, we issue a warning to the user that they've
    cloned an empty repo. The text of that warning doesn't make sense
    for a non-empty repo with an unborn HEAD, so we'll have to
    differentiate the two cases there. We could just use different text,
    but instead let's allow the code to continue down to checkout(),
    which will issue an appropriate warning, like:

      remote HEAD refers to nonexistent ref, unable to checkout

    Continuing down to checkout() will make it easier to do more fixes
    on top (see below).

Note that this patch fixes the case where the other side reports an
unborn head to us using the protocol extension. It _doesn't_ fix the
case where the other side doesn't tell us, we locally guess "master",
and the other side happens to have a "master" which its HEAD doesn't
point. But it doesn't make anything worse there, and it should actually
make it easier to fix that problem on top.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-07 20:57:54 -07:00
Jeff King f77710c504 clone: drop extra newline from warning message
We don't need to put a "\n" in calls to warning(), since it adds one
itself (and the user sees an extra blank line). Drop it, and while we're
here, drop the full-stop from the message, which goes against our
guidelines.

This bug dates all the way back to 8434c2f1af (Build in clone,
2008-04-27), but presumably nobody noticed because it's hard to trigger:
you have to clone a repository whose HEAD is unborn, but which is not
otherwise empty.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-07 20:57:54 -07:00
Ævar Arnfjörð Bjarmason 06f5f8940c cocci: generalize "unused" rule to cover more than "strbuf"
Generalize the newly added "unused.cocci" rule to find more than just
"struct strbuf", let's have it find the same unused patterns for
"struct string_list", as well as other code that uses
similar-looking *_{release,clear,free}() and {release,clear,free}_*()
functions.

We're intentionally loose in accepting e.g. a "strbuf_init(&sb)"
followed by a "string_list_clear(&sb, 0)".  It's assumed that the
compiler will catch any such invalid code, i.e. that our
constructors/destructors don't take a "void *".

See [1] for example of code that would be covered by the
"get_worktrees()" part of this rule. We'd still need work that the
series is based on (we were passing "worktrees" to a function), but
could now do the change in [1] automatically.

1. https://lore.kernel.org/git/Yq6eJFUPPTv%2Fzc0o@coredump.intra.peff.net/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-06 12:24:43 -07:00
Ævar Arnfjörð Bjarmason 4f40f6cb73 cocci: add and apply a rule to find "unused" strbufs
Add a coccinelle rule to remove "struct strbuf" initialization
followed by calling "strbuf_release()" function, without any uses of
the strbuf in the same function.

See the tests in contrib/coccinelle/tests/unused.{c,res} for what it's
intended to find and replace.

The inclusion of "contrib/scalar/scalar.c" is because "spatch" was
manually run on it (we don't usually run spatch on contrib).

Per the "buggy code" comment we also match a strbuf_init() before the
xmalloc(), but we're not seeking to be so strict as to make checks
that the compiler will catch for us redundant. Saying we'll match
either "init" or "xmalloc" lines makes the rule simpler.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-06 12:24:43 -07:00
Shaoxuan Yuan b91a2b6594 mv: add check_dir_in_index() and solve general dir check issue
Originally, moving a <source> directory which is not on-disk due
to its existence outside of sparse-checkout cone, "giv mv" command
errors out with "bad source".

Add a helper check_dir_in_index() function to see if a directory
name exists in the index. Also add a SKIP_WORKTREE_DIR bit to mark
such directories.

Change the checking logic, so that such <source> directory makes
"giv mv" command warns with "advise_on_updating_sparse_paths()"
instead of "bad source"; also user now can supply a "--sparse" flag so
this operation can be carried out successfully.

Helped-by: Victoria Dye <vdye@github.com>
Helped-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Shaoxuan Yuan <shaoxuan.yuan02@gmail.com>
Acked-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-01 14:50:16 -07:00
Shaoxuan Yuan 24ea81d9ac mv: use flags mode for update_mode
As suggested by Derrick [1], move the in-line definition of
"enum update_mode" to the top of the file and make it use "flags"
mode (each state is a different bit in the word).

Change the flag assignments from '=' (single assignment) to '|='
(additive). Also change flag evaluation from '==' to '&', etc.

[1] https://lore.kernel.org/git/22aadea2-9330-aa9e-7b6a-834585189144@github.com/

Helped-by: Victoria Dye <vdye@github.com>
Helped-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Shaoxuan Yuan <shaoxuan.yuan02@gmail.com>
Acked-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-01 14:50:16 -07:00
Shaoxuan Yuan 8a26a3915f mv: check if <destination> exists in index to handle overwriting
Originally, moving a sparse file into cone can result in unwarned
overwrite of existing entry. The expected behavior is that if the
<destination> exists in the entry, user should be prompted to supply
a [-f|--force] to carry out the operation, or the operation should
fail.

Add a check mechanism to do that.

Signed-off-by: Shaoxuan Yuan <shaoxuan.yuan02@gmail.com>
Acked-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-01 14:50:16 -07:00
Shaoxuan Yuan 6645b03ca5 mv: check if out-of-cone file exists in index with SKIP_WORKTREE bit
Originally, moving a <source> file which is not on-disk but exists in
index as a SKIP_WORKTREE enabled cache entry, "giv mv" command errors
out with "bad source".

Change the checking logic, so that such <source>
file makes "giv mv" command warns with "advise_on_updating_sparse_paths()"
instead of "bad source"; also user now can supply a "--sparse" flag so
this operation can be carried out successfully.

Signed-off-by: Shaoxuan Yuan <shaoxuan.yuan02@gmail.com>
Acked-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-01 14:50:16 -07:00
Shaoxuan Yuan 7889755bae mv: decouple if/else-if checks using goto
Previous if/else-if chain are highly nested and hard to develop/extend.

Refactor to decouple this if/else-if chain by using goto to jump ahead.

Suggested-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Shaoxuan Yuan <shaoxuan.yuan02@gmail.com>
Acked-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-01 14:50:16 -07:00
Shaoxuan Yuan 707fa2f76a mv: update sparsity after moving from out-of-cone to in-cone
Originally, "git mv" a sparse file from out-of-cone to
in-cone does not update the moved file's sparsity (remove its
SKIP_WORKTREE bit). And the corresponding cache entry is, unexpectedly,
not checked out in the working tree.

Update the behavior so that:
1. Moving from out-of-cone to in-cone removes the SKIP_WORKTREE bit from
   corresponding cache entry.
2. The moved cache entry is checked out in the working tree to reflect
   the updated sparsity.

Helped-by: Victoria Dye <vdye@github.com>
Signed-off-by: Shaoxuan Yuan <shaoxuan.yuan02@gmail.com>
Acked-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-01 14:50:16 -07:00
Ævar Arnfjörð Bjarmason ece3974ba6 pull: fix a "struct oid_array" memory leak
Fix a memory leak introduced in 44c175c7a4 (pull: error on no merge
candidates, 2015-06-18). As a result we can mark several tests as
passing with SANITIZE=leak using "TEST_PASSES_SANITIZE_LEAK=true".

Removing the "int ret = 0" assignment added here in a6d7eb2c7a (pull:
optionally rebase submodules (remote submodule changes only),
2017-06-23) is not a logic error, it could always have been left
uninitialized (as "int ret"), now that we'll use the "ret" from the
upper scope we can drop the assignment in the "opt_rebase" branch.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-01 11:43:43 -07:00
Ævar Arnfjörð Bjarmason 27472b5195 cat-file: fix a common "struct object_context" memory leak
Fix a memory leak where "cat-file" will leak the "path" member. See
e5fba602e5 (textconv: support for cat_file, 2010-06-15) for the code
that introduced the offending get_oid_with_context() call (called
get_sha1_with_context() at the time).

As a result we can mark several tests as passing with SANITIZE=leak
using "TEST_PASSES_SANITIZE_LEAK=true".

As noted in dc944b65f1 (get_sha1_with_context: dynamically allocate
oc->path, 2017-05-19) callers must free the "path" member. That same
commit added the relevant free() to this function, but we weren't
catching cases where we'd return early.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-01 11:43:43 -07:00
Ævar Arnfjörð Bjarmason 55916bba0f gc: fix a memory leak
Fix a memory leak in code added in 41abfe15d9 (maintenance: add
pack-refs task, 2021-02-09), we need to call strvec_clear() on the
"struct strvec" that we initialized.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-01 11:43:43 -07:00
Ævar Arnfjörð Bjarmason 33d0dda633 checkout: avoid "struct unpack_trees_options" leak
In 1c41d2805e (unpack_trees_options: free messages when done,
2018-05-21) we started calling clear_unpack_trees_porcelain() on this
codepath, but missed this error path.

We could call clear_unpack_trees_porcelain() just before we error()
and return when unmerged_cache() fails, but the more correct fix is to
not have the unmerged_cache() check happen in the middle of our
"topts" setup.

Before 23cbf11b5c (merge-recursive: porcelain messages for checkout,
2010-08-11) we would not malloc() to setup our "topts", which is when
this started to leak on the error path.

Before that this code wasn't conflating the setup of "topts" and the
unmerged_cache() call in any meaningful way. The initial version in
782c2d65c2 (Build in checkout, 2008-02-07) just does a "memset" of
it, and initializes a single struct member.

Then in 8ccba008ee (unpack-trees: allow Porcelain to give different
error messages, 2008-05-17) we added the initialization of the error
message, which as noted above finally started leaking in 23cbf11b5c.

Let's fix the memory leak, and avoid future issues by initializing the
"topts" with a helper function. There are no functional changes here.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-01 11:43:43 -07:00
Ævar Arnfjörð Bjarmason e72e12cc02 merge-file: fix memory leaks on error path
Fix a memory leak in "merge-file", we need to loop over the "mmfs"
array and free() what we've got so far when we error out. As a result
we can mark a test as passing with SANITIZE=leak using
"TEST_PASSES_SANITIZE_LEAK=true".

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-01 11:43:43 -07:00
Ævar Arnfjörð Bjarmason 480a0e30a7 merge-file: refactor for subsequent memory leak fix
Refactor the code in builtin/merge-file.c to:

 * Use the initializer to zero out "mmfs", and use modern C syntax for
   the rest.

 * Refactor the the inner loop to use a variable and "if/else if"
   pattern followed by "return". This will make a change to change it to
   a "goto cleanup" pattern smaller.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-01 11:43:43 -07:00
Ævar Arnfjörð Bjarmason d90dafbe31 cat-file: fix a memory leak in --batch-command mode
Fix a memory leak introduced in 440c705ea6 (cat-file: add
--batch-command mode, 2022-02-18). The free_cmds() function was only
called on "queued_nr" if we had a "flush" command. As the "without
flush for blob info" test added in the same commit shows we can't rely
on that, so let's call free_cmds() again at the end.

Since "nr" follows the usual pattern of being set to 0 if we've
free()'d the memory already it's OK to call it twice, even in cases
where we are doing a "flush".

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-01 11:43:43 -07:00
Ævar Arnfjörð Bjarmason fd74ac95ac revert: free "struct replay_opts" members
Call the release_revisions() function added in
1878b5edc0 (revision.[ch]: provide and start using a
release_revisions(), 2022-04-13) in cmd_revert(), as well as freeing
the xmalloc()'d "revs" member itself.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-01 11:43:42 -07:00
Ævar Arnfjörð Bjarmason 74a06a9f21 clone: fix memory leak in wanted_peer_refs()
Fix a memory leak added in 0ec4b1650c (clone: fix ref selection in
--single-branch --branch=xxx, 2012-06-22).

Whether we get our "remote_head" from copy_ref() directly, or with a
call to guess_remote_head() it'll be the result of a copy_ref() in
either case, as guess_remote_head() is a wrapper for copy_ref() (or it
returns NULL).

We can't mark any tests passing passing with SANITIZE=leak using
"TEST_PASSES_SANITIZE_LEAK=true" as a result of this change, but
e.g. "t/t1500-rev-parse.sh" now gets closer to passing.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-01 11:43:42 -07:00
Ævar Arnfjörð Bjarmason 99b6c45d8f check-ref-format: fix trivial memory leak
Fix a memory leak in "git check-ref-format" that's been present in the
code in one form or another since 38eedc634b (git check-ref-format
--print, 2009-10-12), the code got substantially refactored in
cfbe22f03f (check-ref-format: handle subcommands in separate
functions, 2010-08-05).

As a result we can mark a test as passing with SANITIZE=leak using
"TEST_PASSES_SANITIZE_LEAK=true".

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-01 11:43:42 -07:00
Glen Choo 5ad87271cf submodule--helper: remove display path helper
All invocations of do_get_submodule_displaypath() pass
get_super_prefix() as the super_prefix arg, which is exactly the same
as get_submodule_displaypath().

Replace all calls to do_get_submodule_displaypath() with
get_submodule_displaypath(), and since it has no more callers, remove
it.

Signed-off-by: Glen Choo <chooglen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-30 22:41:46 -07:00
Glen Choo d7a714fddc submodule--helper update: use --super-prefix
Unlike the other subcommands, "git submodule--helper update" uses the
"--recursive-prefix" flag instead of "--super-prefix". The two flags are
otherwise identical (they only serve to compute the 'display path' of a
submodule), except that there is a dedicated helper function to get the
value of "--super-prefix".

This inconsistency exists because "git submodule update" used to pass
"--recursive-prefix" between shell and C (introduced in [1]) before
"--super-prefix" was introduced (in [2]), and for simplicity, we kept
this name when "git submodule--helper update" was created.

Remove "--recursive-prefix" and its associated code from "git
submodule--helper update", replacing it with "--super-prefix".

To use "--super-prefix", module_update is marked with
SUPPORT_SUPER_PREFIX. Note that module_clone must also be marked with
SUPPORT_SUPER_PREFIX, otherwise the "git submodule--helper clone"
subprocess will fail check because "--super-prefix" is propagated via
the environment.

[1] 48308681b0 (git submodule update: have a dedicated helper for
cloning, 2016-02-29)
[2] 74866d7579 (git: make super-prefix option, 2016-10-07)

Signed-off-by: Glen Choo <chooglen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-30 22:41:46 -07:00
Ævar Arnfjörð Bjarmason b0f8b21305 submodule--helper: remove unused SUPPORT_SUPER_PREFIX flags
Remove the SUPPORT_SUPER_PREFIX flag from "add", "init" and
"summary". For the "add" command it hasn't been used since [1],
likewise for "init" and "summary" since [2] and [3], respectively.

As implemented in 74866d7579 (git: make super-prefix option,
2016-10-07) the SUPPORT_SUPER_PREFIX flag in git.c applies for the
entire command, but as implemented in 89c8626557 (submodule helper:
support super prefix, 2016-12-08) we assert here in
cmd_submodule__helper() that we're not getting the flag unexpectedly.

1. 8c8195e9c3 (submodule--helper: introduce add-clone subcommand,
   2021-07-10)
2. 6e7c14e65c (submodule update --init: display correct path from
   submodule, 2017-01-06)
3. 1cf823d8f0 (submodule: remove unnecessary `prefix` based option
   logic, 2021-06-22)

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Glen Choo <chooglen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-30 22:41:45 -07:00
Glen Choo 58cec298f1 submodule--helper: use correct display path helper
Replace a chunk of code in update_submodule() with an equivalent
do_get_submodule_displaypath() invocation. This is already tested by
t/t7406-submodule-update.sh:'submodule update --init --recursive from
subdirectory', so no tests are added.

The two are equivalent because:

- Exactly one of recursive_prefix|prefix is non-NULL at a time; prefix
  is set at the superproject level, and recursive_prefix is set when
  recursing into submodules. There is also a BUG() statement in
  get_submodule_displaypath() that asserts that both cannot be non-NULL.

- In get_submodule_displaypath(), get_super_prefix() always returns NULL
  because "--super-prefix" is never passed. Thus calling it is
  equivalent to calling do_get_submodule_displaypath() with super_prefix
  = NULL.

Therefore:

- When recursive_prefix is non-NULL, prefix is NULL, and thus
  get_submodule_displaypath() just returns prefixed_path. This is
  identical to calling do_get_submodule_displaypath() with super_prefix
  = recursive_prefix because the return value is still the concatenation
  of recursive_prefix + update_data->sm_path.

- When prefix is non-NULL, prefixed_path = update_data->sm_path. Thus
  calling get_submodule_displaypath() with prefixed_path is equivalent
  to calling do_get_submodule_displaypath() with update_data->sm_path

Signed-off-by: Glen Choo <chooglen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-30 22:41:45 -07:00
Glen Choo cb49e1e8d3 submodule--helper: don't recreate recursive prefix
update_submodule() uses duplicated code to compute
update_data->displaypath and next.recursive_prefix. The latter is just
the former with "/" appended to it, and since update_data->displaypath
not changed outside of this statement, we can just reuse the already
computed result.

We can go one step further and remove the reference to
next.recursive_prefix altogether. Since it is only used in
update_data_to_args() (to compute the "--recursive-prefix" flag for the
recursive update child process) we can just use the already computed
.displaypath value of there.

Delete the duplicated code, and remove the unnecessary reference to
next.recursive_prefix. As a bonus, this fixes a memory leak where
prefixed_path was never freed (this leak was first reported in [1]).

[1] https://lore.kernel.org/git/877a45867ae368bf9e053caedcb6cf421e02344d.1655336146.git.gitgitgadget@gmail.com

Signed-off-by: Glen Choo <chooglen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-30 22:41:45 -07:00
Glen Choo 618b8445d9 submodule--helper update: use display path helper
There are two locations in prepare_to_clone_next_submodule() that
manually calculate the submodule display path, but should just use
do_get_submodule_displaypath() for consistency.

Do this replacement and reorder the code slightly to avoid computing
the display path twice.

Until the preceding commit this code had never been tested, with our
newly added tests we can see that both these sites have been computing
the display path incorrectly ever since they were introduced in
48308681b0 (git submodule update: have a dedicated helper for cloning,
2016-02-29) [1]:

- The first hunk puts a "/" between recursive_prefix and ce->name, but
  recursive_prefix already ends with "/".
- The second hunk calls relative_path() on recursive_prefix and
  ce->name, but relative_path() only makes sense when both paths share
  the same base directory. This is never the case here:
  - recursive_prefix is the path from the topmost superproject to the
    current submodule
  - ce->name is the path from the root of the current submodule to its
    submodule.
  so, e.g. recursive_prefix="super" and ce->name="submodule" produces
  displayname="../super" instead of "super/submodule".

[1] I verified this by applying the tests to 48308681b0.

Signed-off-by: Glen Choo <chooglen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-30 22:41:45 -07:00
Junio C Hamano c9e221b124 Merge branch 'ab/submodule-cleanup' into gc/submodule-use-super-prefix
* ab/submodule-cleanup:
  git-sh-setup.sh: remove "say" function, change last users
  git-submodule.sh: use "$quiet", not "$GIT_QUIET"
  submodule--helper: eliminate internal "--update" option
  submodule--helper: understand --checkout, --merge and --rebase synonyms
  submodule--helper: report "submodule" as our name in some "-h" output
  submodule--helper: rename "absorb-git-dirs" to "absorbgitdirs"
  submodule update: remove "-v" option
  submodule--helper: have --require-init imply --init
  git-submodule.sh: remove unused top-level "--branch" argument
  git-submodule.sh: make the "$cached" variable a boolean
  git-submodule.sh: remove unused $prefix variable
  git-submodule.sh: remove unused sanitize_submodule_env()
2022-06-30 15:43:06 -07:00
Glen Choo b788fc671b submodule--helper: eliminate internal "--update" option
Follow-up on the preceding commit which taught "git submodule--helper
update" to understand "--merge", "--checkout" and "--rebase" and use
those options instead of "--update=(rebase|merge|checkout|none)" when
the command invokes itself.

Unlike the preceding change this isn't strictly necessary to
eventually change "git-submodule.sh" so that it invokes "git
submodule--helper update" directly, but let's remove this
inconsistency in the command-line interface. We shouldn't need to
carry special synonyms for existing options in "git submodule--helper"
when that command can use the primary documented names instead.

But, as seen in the post-image this makes the control flow within
"builtin/submodule--helper.c" simpler, we can now write directly to
the "update_default" member of "struct update_data" when parsing the
options in "module_update()".

Signed-off-by: Glen Choo <chooglen@google.com>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-28 13:13:18 -07:00
Ævar Arnfjörð Bjarmason 8f12108c29 submodule--helper: understand --checkout, --merge and --rebase synonyms
Understand --checkout, --merge and --rebase synonyms for
--update={checkout,merge,rebase}, as well as the short options that
'git submodule' itself understands.

This removes a difference between the CLI API of "git submodule" and
"git submodule--helper", making it easier to make the latter an alias
for the former. See 48308681b0 (git submodule update: have a
dedicated helper for cloning, 2016-02-29) for the initial addition of
--update.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-28 13:13:17 -07:00
Ævar Arnfjörð Bjarmason 36d45163b6 submodule--helper: report "submodule" as our name in some "-h" output
Change the user-facing "git submodule--helper" commands so that
they'll report their name as being "git submodule". To a user these
commands are internal implementation details, and it doesn't make
sense to emit usage about an internal helper when "git submodule" is
invoked with invalid options.

Before this we'd emit e.g.:

	$ git submodule absorbgitdirs --blah
	error: unknown option `blah'
	usage: git submodule--helper absorbgitdirs [<options>] [<path>...]
	[...]
And:

	$ git submodule set-url -- --
	usage: git submodule--helper set-url [--quiet] <path> <newurl>
	[...]

Now we'll start with "usage: git submodule [...]" in both of those
cases. This change does not alter the "list", "name", "clone",
"config" and "create-branch" commands, those are internal-only (as an
aside; their usage info should probably invoke BUG(...)). This only
changes the user-facing commands.

The "status", "deinit" and "update" commands are not included in this
change, because their usage information already used "submodule"
rather than "submodule--helper".

I don't think it's currently possible to emit some of this usage
information in practice, as git-submodule.sh will catch unknown
options, and e.g. it doesn't seem to be possible to get "add" to emit
its usage information from "submodule--helper".

Though that change may be superfluous now, it's also harmless, and
will allow us to eventually dispatch further into "git
submodule--helper" from git-submodule.sh, while emitting the correct
usage output.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-28 13:13:17 -07:00
Ævar Arnfjörð Bjarmason 6e556c412e submodule--helper: rename "absorb-git-dirs" to "absorbgitdirs"
Rename the "absorb-git-dirs" subcommand to "absorbgitdirs", which is
what the "git submodule" command itself has called it since the
subcommand was implemented in f6f8586140 (submodule: add
absorb-git-dir function, 2016-12-12).

Having these two be different will make it more tedious to dispatch to
eventually dispatch "git submodule--helper" directly, as we'd need to
retain this name mapping. So let's get rid of this needless
inconsistency.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-28 13:13:17 -07:00
Ævar Arnfjörð Bjarmason d9c7f69aaa submodule--helper: have --require-init imply --init
Adjust code added in 0060fd1511 (clone --recurse-submodules: prevent
name squatting on Windows, 2019-09-12) to have the internal
--require-init option imply --init, rather than having
"git-submodule.sh" add it implicitly.

This change doesn't make any difference now, but eliminates another
special-case where "git submodule--helper update"'s behavior was
different from "git submodule update". This will make it easier to
eventually replace the cmd_update() function in git-submodule.sh.

We'll still need to keep the distinction between "--init" and
"--require-init" in git-submodule.sh. Once cmd_update() gets
re-implemented in C we'll be able to change variables and other code
related to that, but not yet.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-28 13:13:17 -07:00
Elijah Newren 7976721d17 merge-tree: add a --allow-unrelated-histories flag
Folks may want to merge histories that have no common ancestry; provide
a flag with the same name as used by `git merge` to allow this.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-22 16:10:06 -07:00
Elijah Newren 7c48b27822 merge-tree: allow ls-files -u style info to be NUL terminated
Much as `git ls-files` has a -z option, let's add one to merge-tree so
that the conflict-info section can be NUL terminated (and avoid quoting
of unusual filenames).

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-22 16:10:06 -07:00
Elijah Newren de90581141 merge-ort: optionally produce machine-readable output
With the new `detailed` parameter, a new mode can be triggered when
displaying the merge messages: The `detailed` mode prints NUL-delimited
fields of the following form:

	<path-count> NUL <path>... NUL <conflict-type> NUL <message>

The `<path-count>` field determines how many `<path>` fields there are.

The intention of this mode is to support server-side operations, where
worktree-less merges can lead to conflicts and depending on the type
and/or path count, the caller might know how to handle said conflict.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-22 16:10:06 -07:00
Elijah Newren b520bc6caa merge-tree: provide easy access to ls-files -u style info
Much like `git merge` updates the index with information of the form
    (mode, oid, stage, name)
provide this output for conflicted files for merge-tree as well.
Provide a --name-only option for users to exclude the mode, oid, and
stage and only get the list of conflicted filenames.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-22 16:10:06 -07:00
Elijah Newren 7fa3338870 merge-tree: provide a list of which files have conflicts
Callers of `git merge-tree --write-tree` will often want to know which
files had conflicts.  While they could potentially attempt to parse the
CONFLICT notices printed, those messages are not meant to be machine
readable.  Provide a simpler mechanism of just printing the files (in
the same format as `git ls-files` with quoting, but restricted to
unmerged files) in the output before the free-form messages.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-22 16:10:06 -07:00
Elijah Newren a1a7811975 merge-tree: support including merge messages in output
When running `git merge-tree --write-tree`, we previously would only
return an exit status reflecting the cleanness of a merge, and print out
the toplevel tree of the resulting merge.  Merges also have
informational messages, such as:
  * "Auto-merging <PATH>"
  * "CONFLICT (content): ..."
  * "CONFLICT (file/directory)"
  * etc.
In fact, when non-content conflicts occur (such as file/directory,
modify/delete, add/add with differing modes, rename/rename (1to2),
etc.), these informational messages may be the only notification the
user gets since these conflicts are not representable in the contents
of the file.

Add a --[no-]messages option so that callers can request these messages
be included at the end of the output.  Include such messages by default
when there are conflicts, and omit them by default when the merge is
clean.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-22 16:10:06 -07:00
Elijah Newren 1f0c3a29da merge-tree: implement real merges
This adds the ability to perform real merges rather than just trivial
merges (meaning handling three way content merges, recursive ancestor
consolidation, renames, proper directory/file conflict handling, and so
forth).  However, unlike `git merge`, the working tree and index are
left alone and no branch is updated.

The only output is:
  - the toplevel resulting tree printed on stdout
  - exit status of 0 (clean), 1 (conflicts present), anything else
    (merge could not be performed; unknown if clean or conflicted)

This output is meant to be used by some higher level script, perhaps in
a sequence of steps like this:

   NEWTREE=$(git merge-tree --write-tree $BRANCH1 $BRANCH2)
   test $? -eq 0 || die "There were conflicts..."
   NEWCOMMIT=$(git commit-tree $NEWTREE -p $BRANCH1 -p $BRANCH2)
   git update-ref $BRANCH1 $NEWCOMMIT

Note that higher level scripts may also want to access the
conflict/warning messages normally output during a merge, or have quick
access to a list of files with conflicts.  That is not available in this
preliminary implementation, but subsequent commits will add that
ability (meaning that NEWTREE would be a lot more than a tree in the
case of conflicts).

This also marks the traditional trivial merge of merge-tree as
deprecated.  The trivial merge not only had limited applicability, the
output format was also difficult to work with (and its format
undocumented), and will generally be less performant than real merges.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-22 16:10:05 -07:00
Elijah Newren 6ec755a0e1 merge-tree: add option parsing and initial shell for real merge function
Let merge-tree accept a `--write-tree` parameter for choosing real
merges instead of trivial merges, and accept an optional
`--trivial-merge` option to get the traditional behavior.  Note that
these accept different numbers of arguments, though, so these names
need not actually be used.

Note that real merges differ from trivial merges in that they handle:
  - three way content merges
  - recursive ancestor consolidation
  - renames
  - proper directory/file conflict handling
  - etc.
Basically all the stuff you'd expect from `git merge`, just without
updating the index and working tree.  The initial shell added here does
nothing more than die with "real merges are not yet implemented", but
that will be fixed in subsequent commits.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-22 16:10:05 -07:00
Elijah Newren 55e48f6bf7 merge-tree: move logic for existing merge into new function
In preparation for adding a non-trivial merge capability to merge-tree,
move the existing merge logic for trivial merges into a new function.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-22 16:10:05 -07:00
Elijah Newren 70176b7015 merge-tree: rename merge_trees() to trivial_merge_trees()
merge-recursive.h defined its own merge_trees() function, different than
the one found in builtin/merge-tree.c.  That was okay in the past, but
we want merge-tree to be able to use the merge-ort functions, which will
end up including merge-recursive.h.  Rename the function found in
builtin/merge-tree.c to avoid the conflict.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-22 16:10:05 -07:00
Carlos López 68437ede53 grep: add --max-count command line option
This patch adds a command line option analogous to that of GNU
grep(1)'s -m / --max-count, which users might already be used to.
This makes it possible to limit the amount of matches shown in the
output while keeping the functionality of other options such as -C
(show code context) or -p (show containing function), which would be
difficult to do with a shell pipeline (e.g. head(1)).

Signed-off-by: Carlos López 00xc@protonmail.com
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-22 13:23:29 -07:00
Richard Oliver 817b0f6027 mktree: do not check type of remote objects
With 31c8221a (mktree: validate entry type in input, 2009-05-14), we
called the sha1_object_info() API to obtain the type information, but
allowed the call to silently fail when the object was missing locally,
so that we can sanity-check the types opportunistically when the
object did exist.

The implementation is understandable because back then there was no
lazy/on-demand downloading of individual objects from the promisor
remotes that causes a long delay and materializes the object, hence
defeating the point of using "--missing".  The design is hurting us
now.

We could bypass the opportunistic type/mode consistency check
altogether when "--missing" is given, but instead, use the
oid_object_info_extended() API and tell it that we are only interested
in objects that locally exist and are immediately available by passing
OBJECT_INFO_SKIP_FETCH_OBJECT bit to it.  That way, we will still
retain the cheap and opportunistic sanity check for local objects.

Signed-off-by: Richard Oliver <roliver@roku.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-21 10:12:15 -07:00
Jeff King 9bef0b1e6e branch: drop unused worktrees variable
After b489b9d9aa (branch: use branch_checked_out() when deleting refs,
2022-06-14), we no longer look at our local "worktrees" variable, since
branch_checked_out() handles it under the hood. The compiler didn't
notice the unused variable because we call functions to initialize and
free it (so it's not totally unused, it just doesn't do anything
useful).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-21 08:52:37 -07:00
Jeff King b2463fc30a fetch: stop passing around unused worktrees variable
In 12d47e3b1f (fetch: use new branch_checked_out() and add tests,
2022-06-14), fetch's update_local_ref() function stopped using its
"worktrees" parameter. It doesn't need it, since the
branch_checked_out() function examines the global worktrees under the
hood.

So we can not only drop the unused parameter from that function, but
also from its entire call chain. And as we do so all the way up to
do_fetch(), we can see that nobody uses it at all, and we can drop the
local variable there entirely.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-21 08:52:32 -07:00
Alexander Shopov 325240dfd7 name-rev: prefix annotate-stdin with '--' in message
This is an option rather than command.  Make the message convey this
similar to the other messages in the file.

Signed-off-by: Alexander Shopov <ash@kambanaria.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-20 16:20:45 -07:00
Jiang Xin b4eda05d58 i18n: fix mismatched camelCase config variables
Some config variables are combinations of multiple words, and we
typically write them in camelCase forms in manpage and translatable
strings. It's not easy to find mismatches for these camelCase config
variables during code reviews, but occasionally they are identified
during localization translations.

To check for mismatched config variables, I introduced a new feature
in the helper program for localization[^1]. The following mismatched
config variables have been identified by running the helper program,
such as "git-po-helper check-pot".

Lowercase in manpage should use camelCase:

 * Documentation/config/http.txt: http.pinnedpubkey

Lowercase in translable strings should use camelCase:

 * builtin/fast-import.c:  pack.indexversion
 * builtin/gc.c:           gc.logexpiry
 * builtin/index-pack.c:   pack.indexversion
 * builtin/pack-objects.c: pack.indexversion
 * builtin/repack.c:       pack.writebitmaps
 * commit.c:               i18n.commitencoding
 * gpg-interface.c:        user.signingkey
 * http.c:                 http.postbuffer
 * submodule-config.c:     submodule.fetchjobs

Mismatched camelCases, choose the former:

 * Documentation/config/transfer.txt: transfer.credentialsInUrl
   remote.c:                          transfer.credentialsInURL

[^1]: https://github.com/git-l10n/git-po-helper

Signed-off-by: Jiang Xin <zhiyou.jx@alibaba-inc.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-17 10:38:26 -07:00
Junio C Hamano e870c5857f Merge branch 'js/misc-fixes'
Assorted fixes to problems found by Coverity.

* js/misc-fixes:
  relative_url(): fix incorrect condition
  pack-mtimes: avoid closing a bogus file descriptor
  read_index_from(): avoid memory leak
  submodule--helper: avoid memory leak when fetching submodules
  submodule-config: avoid memory leak
  fsmonitor: avoid memory leak in `fsm_settings__get_incompatible_msg()`
2022-06-17 10:33:31 -07:00
Jacob Keller 2c80a82e34 remote: handle negative refspecs in git remote show
By default, the git remote show command will query data from remotes to
show data about what might be done on a future git fetch. This process
currently does not handle negative refspecs. This can be confusing,
because the show command will list refs as if they would be fetched. For
example if the fetch refspec "^refs/heads/pr/*", it still displays the
following:

  * remote jdk19
    Fetch URL: git@github.com:openjdk/jdk19.git
    Push  URL: git@github.com:openjdk/jdk19.git
    HEAD branch: master
    Remote branches:
      master tracked
      pr/1   new (next fetch will store in remotes/jdk19)
      pr/2   new (next fetch will store in remotes/jdk19)
      pr/3   new (next fetch will store in remotes/jdk19)
    Local ref configured for 'git push':
      master pushes to master (fast-forwardable)

Fix this by adding an additional check inside of get_ref_states. If a
ref matches one of the negative refspecs, mark it as skipped instead of
marking it as new or tracked.

With this change, we now report remote branches that are skipped due to
negative refspecs properly:

  * remote jdk19
    Fetch URL: git@github.com:openjdk/jdk19.git
    Push  URL: git@github.com:openjdk/jdk19.git
    HEAD branch: master
    Remote branches:
      master tracked
      pr/1   skipped
      pr/2   skipped
      pr/3   skipped
    Local ref configured for 'git push':
      master pushes to master (fast-forwardable)

By showing the refs as skipped, it helps clarify that these references
won't actually be fetched.

This does not properly handle refs going stale due to a newly added
negative refspec. In addition, git remote prune doesn't handle that
negative refspec case either. Fixing that requires digging into
get_stale_heads and handling the case of a ref which exists on the
remote but is omitted due to a negative refspec locally.

Add a new test case which covers the functionality above, as well as a
new expected failure indicating the poor overlap with stale refs.

Reported-by: Pavel Rappo <pavel.rappo@gmail.com>
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-17 10:03:59 -07:00
Johannes Schindelin 41a86b64c0 submodule--helper: avoid memory leak when fetching submodules
In c51f8f94e5 (submodule--helper: run update procedures from C,
2021-08-24), we added code that first obtains the default remote, and
then adds that to a `strvec`.

However, we never released the default remote's memory.

Reported by Coverity.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-16 13:22:03 -07:00
Fangyi Zhou 3b9a5a33c2 builtin/rebase: remove a redundant space in l10n string
Found in l10n.

Signed-off-by: Fangyi Zhou <me@fangyi.io>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-16 11:15:23 -07:00
Junio C Hamano 589bc0942b Merge branch 'po/rebase-preserve-merges'
Various error messages that talk about the removal of
"--preserve-merges" in "rebase" have been strengthened, and "rebase
--abort" learned to get out of a state that was left by an earlier
use of the option.

* po/rebase-preserve-merges:
  rebase: translate a die(preserve-merges) message
  rebase: note `preserve` merges may be a pull config option
  rebase: help users when dying with `preserve-merges`
  rebase.c: state preserve-merges has been removed
2022-06-15 15:09:28 -07:00
Junio C Hamano bfca631634 Merge branch 'jc/revert-show-parent-info'
"git revert" learns "--reference" option to use more human-readable
reference to the commit it reverts in the message template it
prepares for the user.

* jc/revert-show-parent-info:
  revert: --reference should apply only to 'revert', not 'cherry-pick'
  revert: optionally refer to commit in the "reference" format
2022-06-15 15:09:27 -07:00
Fangyi Zhou 1f8496c65f push: fix capitalisation of the option name autoSetupMerge
This was found during l10n process by Jiang Xin.

Reported-by: Jiang Xin <worldhello.net@gmail.com>
Signed-off-by: Fangyi Zhou <me@fangyi.io>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-15 11:45:46 -07:00
Derrick Stolee b489b9d9aa branch: use branch_checked_out() when deleting refs
This is the last current use of find_shared_symref() that can easily be
replaced by branch_checked_out(). The benefit of this switch is that the
code is a bit simpler, but also it is faster on repeated calls.

The remaining uses of find_shared_symref() are non-trivial to remove, so
we probably should not continue in that direction:

* builtin/notes.c uses find_shared_symref() with "NOTES_MERGE_REF"
  instead of "HEAD", so it doesn't have an immediate analogue with
  branch_checked_out(). Perhaps we should consider extending it to
  include that symref in addition to HEAD, BISECT_HEAD, and
  REBASE_HEAD.

* receive-pack.c checks to see if a worktree has a checkout for the ref
  that is being updated. The tricky part is that it can actually decide
  to update the worktree directly instead of just skipping the update.
  This all depends on the receive.denyCurrentBranch config option. The
  implementation currenty cares about receiving the worktree in the
  result, so the current branch_checked_out() prototype is insufficient
  currently. This is something to investigate later, though, since a
  large number of refs could be updated at the same time and using the
  strmap implementation of branch_checked_out() could be beneficial.

Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-15 10:47:19 -07:00
Derrick Stolee 12d47e3b1f fetch: use new branch_checked_out() and add tests
When fetching refs from a remote, it is possible that the refspec will
cause use to overwrite a ref that is checked out in a worktree. The
existing logic in builtin/fetch.c uses a possibly-slow mechanism. Update
those sections to use the new, more efficient branch_checked_out()
helper.

These uses were not previously tested, so add a test case that can be
used for these kinds of collisions. There is only one test now, but more
tests will be added as other consumers of branch_checked_out() are
added.

Note that there are two uses in builtin/fetch.c, but only one of the
messages is tested. This is because the tested check is run before
completing the fetch, and the untested check is not reachable without
concurrent updates to the filesystem. Thus, it is beneficial to keep
that extra check for the sake of defense-in-depth. However, we should
not attempt to test the check, as the effort required is too
complicated to be worth the effort. This use in update_local_ref()
also requires a change in the error message because we no longer have
access to the worktree struct, only the path of the worktree. This error
is so rare that making a distinction between the two is not critical.

Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-15 10:47:18 -07:00
Junio C Hamano 2246937e41 Merge branch 'tb/show-ref-optim'
"git show-ref --heads" (and "--tags") still iterated over all the
refs only to discard refs outside the specified area, which has
been corrected.

* tb/show-ref-optim:
  builtin/show-ref.c: avoid over-iterating with --heads, --tags
2022-06-13 15:53:42 -07:00
Han Xin aaf81223f4 unpack-objects: use stream_loose_object() to unpack large objects
Make use of the stream_loose_object() function introduced in the
preceding commit to unpack large objects. Before this we'd need to
malloc() the size of the blob before unpacking it, which could cause
OOM with very large blobs.

We could use the new streaming interface to unpack all blobs, but
doing so would be much slower, as demonstrated e.g. with this
benchmark using git-hyperfine[0]:

	rm -rf /tmp/scalar.git &&
	git clone --bare https://github.com/Microsoft/scalar.git /tmp/scalar.git &&
	mv /tmp/scalar.git/objects/pack/*.pack /tmp/scalar.git/my.pack &&
	git hyperfine \
		-r 2 --warmup 1 \
		-L rev origin/master,HEAD -L v "10,512,1k,1m" \
		-s 'make' \
		-p 'git init --bare dest.git' \
		-c 'rm -rf dest.git' \
		'./git -C dest.git -c core.bigFileThreshold={v} unpack-objects </tmp/scalar.git/my.pack'

Here we'll perform worse with lower core.bigFileThreshold settings
with this change in terms of speed, but we're getting lower memory use
in return:

	Summary
	  './git -C dest.git -c core.bigFileThreshold=10 unpack-objects </tmp/scalar.git/my.pack' in 'origin/master' ran
	    1.01 ± 0.01 times faster than './git -C dest.git -c core.bigFileThreshold=1k unpack-objects </tmp/scalar.git/my.pack' in 'origin/master'
	    1.01 ± 0.01 times faster than './git -C dest.git -c core.bigFileThreshold=1m unpack-objects </tmp/scalar.git/my.pack' in 'origin/master'
	    1.01 ± 0.02 times faster than './git -C dest.git -c core.bigFileThreshold=1m unpack-objects </tmp/scalar.git/my.pack' in 'HEAD'
	    1.02 ± 0.00 times faster than './git -C dest.git -c core.bigFileThreshold=512 unpack-objects </tmp/scalar.git/my.pack' in 'origin/master'
	    1.09 ± 0.01 times faster than './git -C dest.git -c core.bigFileThreshold=1k unpack-objects </tmp/scalar.git/my.pack' in 'HEAD'
	    1.10 ± 0.00 times faster than './git -C dest.git -c core.bigFileThreshold=512 unpack-objects </tmp/scalar.git/my.pack' in 'HEAD'
	    1.11 ± 0.00 times faster than './git -C dest.git -c core.bigFileThreshold=10 unpack-objects </tmp/scalar.git/my.pack' in 'HEAD'

A better benchmark to demonstrate the benefits of that this one, which
creates an artificial repo with a 1, 25, 50, 75 and 100MB blob:

	rm -rf /tmp/repo &&
	git init /tmp/repo &&
	(
		cd /tmp/repo &&
		for i in 1 25 50 75 100
		do
			dd if=/dev/urandom of=blob.$i count=$(($i*1024)) bs=1024
		done &&
		git add blob.* &&
		git commit -mblobs &&
		git gc &&
		PACK=$(echo .git/objects/pack/pack-*.pack) &&
		cp "$PACK" my.pack
	) &&
	git hyperfine \
		--show-output \
		-L rev origin/master,HEAD -L v "512,50m,100m" \
		-s 'make' \
		-p 'git init --bare dest.git' \
		-c 'rm -rf dest.git' \
		'/usr/bin/time -v ./git -C dest.git -c core.bigFileThreshold={v} unpack-objects </tmp/repo/my.pack 2>&1 | grep Maximum'

Using this test we'll always use >100MB of memory on
origin/master (around ~105MB), but max out at e.g. ~55MB if we set
core.bigFileThreshold=50m.

The relevant "Maximum resident set size" lines were manually added
below the relevant benchmark:

  '/usr/bin/time -v ./git -C dest.git -c core.bigFileThreshold=50m unpack-objects </tmp/repo/my.pack 2>&1 | grep Maximum' in 'origin/master' ran
        Maximum resident set size (kbytes): 107080
    1.02 ± 0.78 times faster than '/usr/bin/time -v ./git -C dest.git -c core.bigFileThreshold=512 unpack-objects </tmp/repo/my.pack 2>&1 | grep Maximum' in 'origin/master'
        Maximum resident set size (kbytes): 106968
    1.09 ± 0.79 times faster than '/usr/bin/time -v ./git -C dest.git -c core.bigFileThreshold=100m unpack-objects </tmp/repo/my.pack 2>&1 | grep Maximum' in 'origin/master'
        Maximum resident set size (kbytes): 107032
    1.42 ± 1.07 times faster than '/usr/bin/time -v ./git -C dest.git -c core.bigFileThreshold=100m unpack-objects </tmp/repo/my.pack 2>&1 | grep Maximum' in 'HEAD'
        Maximum resident set size (kbytes): 107072
    1.83 ± 1.02 times faster than '/usr/bin/time -v ./git -C dest.git -c core.bigFileThreshold=50m unpack-objects </tmp/repo/my.pack 2>&1 | grep Maximum' in 'HEAD'
        Maximum resident set size (kbytes): 55704
    2.16 ± 1.19 times faster than '/usr/bin/time -v ./git -C dest.git -c core.bigFileThreshold=512 unpack-objects </tmp/repo/my.pack 2>&1 | grep Maximum' in 'HEAD'
        Maximum resident set size (kbytes): 4564

This shows that if you have enough memory this new streaming method is
slower the lower you set the streaming threshold, but the benefit is
more bounded memory use.

An earlier version of this patch introduced a new
"core.bigFileStreamingThreshold" instead of re-using the existing
"core.bigFileThreshold" variable[1]. As noted in a detailed overview
of its users in [2] using it has several different meanings.

Still, we consider it good enough to simply re-use it. While it's
possible that someone might want to e.g. consider objects "small" for
the purposes of diffing but "big" for the purposes of writing them
such use-cases are probably too obscure to worry about. We can always
split up "core.bigFileThreshold" in the future if there's a need for
that.

0. https://github.com/avar/git-hyperfine/
1. https://lore.kernel.org/git/20211210103435.83656-1-chiyutianyi@gmail.com/
2. https://lore.kernel.org/git/20220120112114.47618-5-chiyutianyi@gmail.com/

Helped-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Helped-by: Derrick Stolee <stolee@gmail.com>
Helped-by: Jiang Xin <zhiyou.jx@alibaba-inc.com>
Signed-off-by: Han Xin <chiyutianyi@gmail.com>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-13 10:22:36 -07:00
Han Xin a1bf5ca29f unpack-objects: low memory footprint for get_data() in dry_run mode
As the name implies, "get_data(size)" will allocate and return a given
amount of memory. Allocating memory for a large blob object may cause the
system to run out of memory. Before preparing to replace calling of
"get_data()" to unpack large blob objects in latter commits, refactor
"get_data()" to reduce memory footprint for dry_run mode.

Because in dry_run mode, "get_data()" is only used to check the
integrity of data, and the returned buffer is not used at all, we can
allocate a smaller buffer and use it as zstream output. Make the function
return NULL in the dry-run mode, as no callers use the returned buffer.

The "find [...]objects/?? -type f | wc -l" test idiom being used here
is adapted from the same "find" use added to another test in
d9545c7f46 (fast-import: implement unpack limit, 2016-04-25).

Suggested-by: Jiang Xin <zhiyou.jx@alibaba-inc.com>
Signed-off-by: Han Xin <chiyutianyi@gmail.com>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-13 10:22:35 -07:00
Junio C Hamano 4da14b574f Merge branch 'ab/bug-if-bug'
A new bug() and BUG_if_bug() API is introduced to make it easier to
uniformly log "detect multiple bugs and abort in the end" pattern.

* ab/bug-if-bug:
  cache-tree.c: use bug() and BUG_if_bug()
  receive-pack: use bug() and BUG_if_bug()
  parse-options.c: use optbug() instead of BUG() "opts" check
  parse-options.c: use new bug() API for optbug()
  usage.c: add a non-fatal bug() function to go with BUG()
  common-main.c: move non-trace2 exit() behavior out of trace2.c
2022-06-10 15:04:15 -07:00
Junio C Hamano 9e496fffc8 Merge branch 'jh/builtin-fsmonitor-part3'
More fsmonitor--daemon.

* jh/builtin-fsmonitor-part3: (30 commits)
  t7527: improve implicit shutdown testing in fsmonitor--daemon
  fsmonitor--daemon: allow --super-prefix argument
  t7527: test Unicode NFC/NFD handling on MacOS
  t/lib-unicode-nfc-nfd: helper prereqs for testing unicode nfc/nfd
  t/helper/hexdump: add helper to print hexdump of stdin
  fsmonitor: on macOS also emit NFC spelling for NFD pathname
  t7527: test FSMonitor on case insensitive+preserving file system
  fsmonitor: never set CE_FSMONITOR_VALID on submodules
  t/perf/p7527: add perf test for builtin FSMonitor
  t7527: FSMonitor tests for directory moves
  fsmonitor: optimize processing of directory events
  fsm-listen-darwin: shutdown daemon if worktree root is moved/renamed
  fsm-health-win32: force shutdown daemon if worktree root moves
  fsm-health-win32: add polling framework to monitor daemon health
  fsmonitor--daemon: stub in health thread
  fsmonitor--daemon: rename listener thread related variables
  fsmonitor--daemon: prepare for adding health thread
  fsmonitor--daemon: cd out of worktree root
  fsm-listen-darwin: ignore FSEvents caused by xattr changes on macOS
  unpack-trees: initialize fsmonitor_has_run_once in o->result
  ...
2022-06-10 15:04:15 -07:00
Junio C Hamano c21fa3bb54 Merge branch 'ab/env-array'
Rename .env_array member to .env in the child_process structure.

* ab/env-array:
  run-command API users: use "env" not "env_array" in comments & names
  run-command API: rename "env_array" to "env"
2022-06-10 15:04:13 -07:00
Junio C Hamano 5a5ea141e7 revision: mark blobs needed for resolve-undo as reachable
The resolve-undo extension was added to the index in cfc5789a
(resolve-undo: record resolved conflicts in a new index extension
section, 2009-12-25).  This extension records the blob object names
and their modes of conflicted paths when the path gets resolved
(e.g. with "git add"), to allow "undoing" the resolution with
"checkout -m path".  These blob objects should be guarded from
garbage-collection while we have the resolve-undo information in the
index (otherwise unresolve operation may try to use a blob object
that has already been pruned away).

But the code called from mark_reachable_objects() for the index
forgets to do so.  Teach add_index_objects_to_pending() helper to
also add objects referred to by the resolve-undo extension.

Also make matching changes to "fsck", which has code that is fairly
similar to the reachability stuff, but have parallel implementations
for all these stuff, which may (or may not) someday want to be unified.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-09 16:45:07 -07:00
Junio C Hamano d2b11e05e0 Merge branch 'jc/clone-remote-name-leak-fix' into maint
"git clone --origin X" leaked piece of memory that held value read
from the clone.defaultRemoteName configuration variable, which has
been plugged.
source: <xmqqlevl4ysk.fsf@gitster.g>

* jc/clone-remote-name-leak-fix:
  clone: plug a miniscule leak
2022-06-08 14:27:53 -07:00
Junio C Hamano 67c305f722 Merge branch 'ds/midx-normalize-pathname-before-comparison' into maint
The path taken by "git multi-pack-index" command from the end user
was compared with path internally prepared by the tool withut first
normalizing, which lead to duplicated paths not being noticed,
which has been corrected.
source: <pull.1221.v2.git.1650911234.gitgitgadget@gmail.com>

* ds/midx-normalize-pathname-before-comparison:
  cache: use const char * for get_object_directory()
  multi-pack-index: use --object-dir real path
  midx: use real paths in lookup_multi_pack_index()
2022-06-08 14:27:53 -07:00
Junio C Hamano 363d54ff80 Merge branch 'ah/rebase-keep-base-fix' into maint
"git rebase --keep-base <upstream> <branch-to-rebase>" computed the
commit to rebase onto incorrectly, which has been corrected.
source: <20220421044233.894255-1-alexhenrie24@gmail.com>

* ah/rebase-keep-base-fix:
  rebase: use correct base for --keep-base when a branch is given
2022-06-08 14:27:52 -07:00
Junio C Hamano c47b89cde6 Merge branch 'jc/show-branch-g-current' into maint
The "--current" option of "git show-branch" should have been made
incompatible with the "--reflog" mode, but this was not enforced,
which has been corrected.
source: <xmqqh76mf7s4.fsf_-_@gitster.g>

* jc/show-branch-g-current:
  show-branch: -g and --current are incompatible
2022-06-08 14:27:51 -07:00
Junio C Hamano 2da81d1efb Merge branch 'ab/plug-leak-in-revisions'
Plug the memory leaks from the trickiest API of all, the revision
walker.

* ab/plug-leak-in-revisions: (27 commits)
  revisions API: add a TODO for diff_free(&revs->diffopt)
  revisions API: have release_revisions() release "topo_walk_info"
  revisions API: have release_revisions() release "date_mode"
  revisions API: call diff_free(&revs->pruning) in revisions_release()
  revisions API: release "reflog_info" in release revisions()
  revisions API: clear "boundary_commits" in release_revisions()
  revisions API: have release_revisions() release "prune_data"
  revisions API: have release_revisions() release "grep_filter"
  revisions API: have release_revisions() release "filter"
  revisions API: have release_revisions() release "cmdline"
  revisions API: have release_revisions() release "mailmap"
  revisions API: have release_revisions() release "commits"
  revisions API users: use release_revisions() for "prune_data" users
  revisions API users: use release_revisions() with UNLEAK()
  revisions API users: use release_revisions() in builtin/log.c
  revisions API users: use release_revisions() in http-push.c
  revisions API users: add "goto cleanup" for release_revisions()
  stash: always have the owner of "stash_info" free it
  revisions API users: use release_revisions() needing REV_INFO_INIT
  revision.[ch]: document and move code declared around "init"
  ...
2022-06-07 14:10:56 -07:00
Philip Oakley f007713cb1 rebase: translate a die(preserve-merges) message
This is a user facing message for a situation seen in the wild.

Translate it.

Signed-off-by: Philip Oakley <philipoakley@iee.email>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-06 10:45:54 -07:00
Philip Oakley afea77a72a rebase: note preserve merges may be a pull config option
The `--preserve-merges` option was removed by v2.34.0. However
users may not be aware that it is also a Pull configuration option,
which is still offered by major IDE vendors such as Visual Studio.

Extend the `--preserve-merges` die message to also direct users to
the possible use of the `preserve` option in the `pull.rebase` config.
This is an additional 'belt and braces' information statement.

Signed-off-by: Philip Oakley <philipoakley@iee.email>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-06 10:45:54 -07:00
Philip Oakley afd58a0d42 rebase: help users when dying with preserve-merges
Git would die if a "rebase --preserve-merges" was in progress.
Users could neither --quit, --abort, nor --continue the rebase.

Make the `rebase --abort` option available to allow users to remove
traces of any preserve-merges rebase, even if they had upgraded
during a rebase.

One trigger case was an unexpectedly difficult to resolve conflict, as
reported on the `git-users` group.
(https://groups.google.com/g/git-for-windows/c/3jMWbBlXXHM)

Other potential use-cases include git-experts using the portable
'Git on a stick' to help users with an older git version.

Signed-off-by: Philip Oakley <philipoakley@iee.email>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-06 10:45:54 -07:00
Philip Oakley 2f7b9f9e55 rebase.c: state preserve-merges has been removed
Since feebd2d256 (rebase: hide --preserve-merges option, 2019-10-18)
this option is now removed as stated in the subsequent release notes.

Fix and reflow the option tip.

Signed-off-by: Philip Oakley <philipoakley@iee.email>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-06 10:45:54 -07:00
Taylor Blau c0c9d35e27 builtin/show-ref.c: avoid over-iterating with --heads, --tags
When `show-ref` is combined with the `--heads` or `--tags` options, it
can avoid iterating parts of a repository's references that it doesn't
care about.

But it doesn't take advantage of this potential optimization. When this
command was introduced back in 358ddb62cf (Add "git show-ref" builtin
command, 2006-09-15), `for_each_ref_in()` did exist. But since most
repositories don't have many (any?) references that aren't branches or
tags already, this makes little difference in practice.

Though for repositories with a large imbalance of branches and tags (or,
more likely in the case of server operators, many hidden references),
this can make quite a difference. Take, for example, a repository with
500,000 "hidden" references (all of the form "refs/__hidden__/N"), and
a single branch:

    git commit --allow-empty -m "base" &&
    seq 1 500000 | sed 's,\(.*\),create refs/__hidden__/\1 HEAD,' |
      git update-ref --stdin &&
    git pack-refs --all

Outputting the existence of that single branch currently takes on the
order of ~50ms on my machine. The vast majority of this time is wasted
iterating through references that we know we're going to discard.

Instead, teach `show-ref` that it can iterate just "refs/heads" and/or
"refs/tags" when given `--heads` and/or `--tags`, respectively. A few
small interesting things to note:

  - When given either option, we can avoid the general-purpose
    for_each_ref() call altogether, since we know that it won't give us
    any references that we wouldn't filter out already.

  - We can make two separate calls to `for_each_fullref_in()` (and
    avoid, say, the more specialized `for_each_fullref_in_prefixes()`,
    since we know that the set of references enumerated by each is
    disjoint, so we'll never see the same reference appear in both
    calls.

  - We have to use the "fullref" variant (instead of just
    `for_each_branch_ref()` and `for_each_tag_ref()`), since we expect
    fully-qualified reference names to appear in `show-ref`'s output.

When either of `heads_only` or `tags_only` is set, we can eliminate the
strcmp() calls in `builtin/show-ref.c::show_ref()` altogether, since we
know that `show_ref()` will never see a non-branch or tag reference.

Unfortunately, we can't use `for_each_fullref_in_prefixes()` to enhance
`show-ref`'s pattern matching, since `show-ref` patterns match on the
_suffix_ (e.g., the pattern "foo" shows "refs/heads/foo",
"refs/tags/foo", and etc, not "foo/*").

Nonetheless, in our synthetic example above, this provides a significant
speed-up ("git" is roughly v2.36, "git.compile" is this patch):

    $ hyperfine -N 'git show-ref --heads' 'git.compile show-ref --heads'
    Benchmark 1: git show-ref --heads
      Time (mean ± σ):      49.9 ms ±   6.2 ms    [User: 45.6 ms, System: 4.1 ms]
      Range (min … max):    46.1 ms …  73.6 ms    43 runs

    Benchmark 2: git.compile show-ref --heads
      Time (mean ± σ):       2.8 ms ±   0.4 ms    [User: 1.4 ms, System: 1.2 ms]
      Range (min … max):     1.3 ms …   5.6 ms    957 runs

    Summary
      'git.compile show-ref --heads' ran
       18.03 ± 3.38 times faster than 'git show-ref --heads'

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-06 09:56:42 -07:00
Junio C Hamano a50036da1a Merge branch 'tb/cruft-packs'
A mechanism to pack unreachable objects into a "cruft pack",
instead of ejecting them into loose form to be reclaimed later, has
been introduced.

* tb/cruft-packs:
  sha1-file.c: don't freshen cruft packs
  builtin/gc.c: conditionally avoid pruning objects via loose
  builtin/repack.c: add cruft packs to MIDX during geometric repack
  builtin/repack.c: use named flags for existing_packs
  builtin/repack.c: allow configuring cruft pack generation
  builtin/repack.c: support generating a cruft pack
  builtin/pack-objects.c: --cruft with expiration
  reachable: report precise timestamps from objects in cruft packs
  reachable: add options to add_unseen_recent_objects_to_traversal
  builtin/pack-objects.c: --cruft without expiration
  builtin/pack-objects.c: return from create_object_entry()
  t/helper: add 'pack-mtimes' test-tool
  pack-mtimes: support writing pack .mtimes files
  chunk-format.h: extract oid_version()
  pack-write: pass 'struct packing_data' to 'stage_tmp_packfiles'
  pack-mtimes: support reading .mtimes files
  Documentation/technical: add cruft-packs.txt
2022-06-03 14:30:37 -07:00
Junio C Hamano 28db3b7b71 Merge branch 'jx/l10n-workflow-change'
A workflow change for translators are being proposed.

* jx/l10n-workflow-change:
  l10n: Document the new l10n workflow
  Makefile: add "po-init" rule to initialize po/XX.po
  Makefile: add "po-update" rule to update po/XX.po
  po/git.pot: don't check in result of "make pot"
  po/git.pot: this is now a generated file
  Makefile: remove duplicate and unwanted files in FOUND_SOURCE_FILES
  i18n CI: stop allowing non-ASCII source messages in po/git.pot
  Makefile: have "make pot" not "reset --hard"
  Makefile: generate "po/git.pot" from stable LOCALIZED_C
  Makefile: sort source files before feeding to xgettext
2022-06-03 14:30:36 -07:00
Junio C Hamano 16a0e92ddc Merge branch 'tb/geom-repack-with-keep-and-max'
Teach "git repack --geometric" work better with "--keep-pack" and
avoid corrupting the repository when packsize limit is used.

* tb/geom-repack-with-keep-and-max:
  builtin/repack.c: ensure that `names` is sorted
  t7703: demonstrate object corruption with pack.packSizeLimit
  repack: respect --keep-pack with geometric repack
2022-06-03 14:30:36 -07:00
Junio C Hamano c276c21da6 Merge branch 'ds/sparse-sparse-checkout'
"sparse-checkout" learns to work well with the sparse-index
feature.

* ds/sparse-sparse-checkout:
  sparse-checkout: integrate with sparse index
  p2000: add test for 'git sparse-checkout [add|set]'
  sparse-index: complete partial expansion
  sparse-index: partially expand directories
  sparse-checkout: --no-sparse-index needs a full index
  cache-tree: implement cache_tree_find_path()
  sparse-index: introduce partially-sparse indexes
  sparse-index: create expand_index()
  t1092: stress test 'git sparse-checkout set'
  t1092: refactor 'sparse-index contents' test
2022-06-03 14:30:35 -07:00
Junio C Hamano 091680472d Merge branch 'tb/midx-race-in-pack-objects'
The multi-pack-index code did not protect the packfile it is going
to depend on from getting removed while in use, which has been
corrected.

* tb/midx-race-in-pack-objects:
  builtin/pack-objects.c: ensure pack validity from MIDX bitmap objects
  builtin/pack-objects.c: ensure included `--stdin-packs` exist
  builtin/pack-objects.c: avoid redundant NULL check
  pack-bitmap.c: check preferred pack validity when opening MIDX bitmap
2022-06-03 14:30:35 -07:00
Junio C Hamano b3b2ddced2 Merge branch 'ds/bundle-uri'
Preliminary code refactoring around transport and bundle code.

* ds/bundle-uri:
  bundle.h: make "fd" version of read_bundle_header() public
  remote: allow relative_url() to return an absolute url
  remote: move relative_url()
  http: make http_get_file() external
  fetch-pack: move --keep=* option filling to a function
  fetch-pack: add a deref_without_lazy_fetch_extended()
  dir API: add a generalized path_match_flags() function
  connect.c: refactor sending of agent & object-format
2022-06-03 14:30:34 -07:00
Junio C Hamano 83937e9592 Merge branch 'ns/batch-fsync'
Introduce a filesystem-dependent mechanism to optimize the way the
bits for many loose object files are ensured to hit the disk
platter.

* ns/batch-fsync:
  core.fsyncmethod: performance tests for batch mode
  t/perf: add iteration setup mechanism to perf-lib
  core.fsyncmethod: tests for batch mode
  test-lib-functions: add parsing helpers for ls-files and ls-tree
  core.fsync: use batch mode and sync loose objects by default on Windows
  unpack-objects: use the bulk-checkin infrastructure
  update-index: use the bulk-checkin infrastructure
  builtin/add: add ODB transaction around add_files_to_cache
  cache-tree: use ODB transaction around writing a tree
  core.fsyncmethod: batched disk flushes for loose-objects
  bulk-checkin: rebrand plug/unplug APIs as 'odb transactions'
  bulk-checkin: rename 'state' variable and separate 'plugged' boolean
2022-06-03 14:30:34 -07:00
Junio C Hamano 377d347eb3 Merge branch 'en/sparse-cone-becomes-default'
Deprecate non-cone mode of the sparse-checkout feature.

* en/sparse-cone-becomes-default:
  Documentation: some sparsity wording clarifications
  git-sparse-checkout.txt: mark non-cone mode as deprecated
  git-sparse-checkout.txt: flesh out pattern set sections a bit
  git-sparse-checkout.txt: add a new EXAMPLES section
  git-sparse-checkout.txt: shuffle some sections and mark as internal
  git-sparse-checkout.txt: update docs for deprecation of 'init'
  git-sparse-checkout.txt: wording updates for the cone mode default
  sparse-checkout: make --cone the default
  tests: stop assuming --no-cone is the default mode for sparse-checkout
2022-06-03 14:30:33 -07:00
Ævar Arnfjörð Bjarmason b3193252c4 run-command API users: use "env" not "env_array" in comments & names
Follow-up on a preceding commit which changed all references to the
"env_array" when referring to the "struct child_process" member. These
changes are all unnecessary for the compiler, but help the code's
human readers.

All the comments that referred to "env_array" have now been updated,
as well as function names and variables that had "env_array" in their
name, they now refer to "env".

In addition the "out" name for the submodule.h prototype was
inconsistent with the function definition's use of "env_array" in
submodule.c. Both of them use "env" now.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-02 14:31:27 -07:00
Ævar Arnfjörð Bjarmason 29fda24dd1 run-command API: rename "env_array" to "env"
Start following-up on the rename mentioned in c7c4bdeccf (run-command
API: remove "env" member, always use "env_array", 2021-11-25) of
"env_array" to "env".

The "env_array" name was picked in 19a583dc39 (run-command: add
env_array, an optional argv_array for env, 2014-10-19) because "env"
was taken. Let's not forever keep the oddity of "*_array" for this
"struct strvec", but not for its "args" sibling.

This commit is almost entirely made with a coccinelle rule[1]. The
only manual change here is in run-command.h to rename the struct
member itself and to change "env_array" to "env" in the
CHILD_PROCESS_INIT initializer.

The rest of this is all a result of applying [1]:

 * make contrib/coccinelle/run_command.cocci.patch
 * patch -p1 <contrib/coccinelle/run_command.cocci.patch
 * git add -u

1. cat contrib/coccinelle/run_command.pending.cocci
   @@
   struct child_process E;
   @@
   - E.env_array
   + E.env

   @@
   struct child_process *E;
   @@
   - E->env_array
   + E->env

I've avoided changing any comments and derived variable names here,
that will all be done in the next commit.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-02 14:31:16 -07:00
Ævar Arnfjörð Bjarmason 07b1d8f184 receive-pack: use bug() and BUG_if_bug()
Amend code added in a6a8431968 (receive-pack.c: shorten the
execute_commands loop over all commands, 2015-01-07) and amended to
hard die in b6a4788586 (receive-pack.c: die instead of error in case
of possible future bug, 2015-01-07) to use the new bug() function
instead.

Let's also rename the warn_if_*() function that code is in to
BUG_if_*(), its name became outdated in b6a4788586.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-02 12:51:35 -07:00
Junio C Hamano 191faaf726 revert: --reference should apply only to 'revert', not 'cherry-pick'
As 'revert' and 'cherry-pick' share a lot of code, it is easy to
modify the behaviour of one command and inadvertently affect the
other.  An earlier change to teach the '--reference' option and the
'revert.reference' configuration variable to the former was not
careful enough and 'cherry-pick --reference' wasn't rejected as an
error.

It is possible to think 'cherry-pick -x' might benefit from the
'--reference' option, but it is fundamentally different from
'revert' in at least two ways to make it questionable:

 - 'revert' names a commit that is ancestor of the resulting commit,
   so an abbreviated object name with human readable title is
   sufficient to identify the named commit uniquely without using
   the full object name.  On the other hand, 'cherry-pick'
   usually [*] picks a commit that is not an ancestor.  It might be
   even picking a private commit that never becomes part of the
   public history.

 - The whole commit message of 'cherry-pick' is a copy of the
   original commit, and there is nothing gained to repeat only the
   title part on 'cherry-picked from' message.

[*] well, you could revert and then you can pick the original that
    was reverted to get back to where you were, but then you can
    revert the revert to do the same thing.

Helped-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-31 09:40:51 -07:00
Junio C Hamano 1fc1879839 Merge branch 'js/use-builtin-add-i'
"git add -i" was rewritten in C some time ago and has been in
testing; the reimplementation is now exposed to general public by
default.

* js/use-builtin-add-i:
  add -i: default to the built-in implementation
  t2016: require the PERL prereq only when necessary
2022-05-30 23:24:03 -07:00
Junio C Hamano 43966ab315 revert: optionally refer to commit in the "reference" format
A typical "git revert" commit uses the full title of the original
commit in its title, and starts its body of the message with:

    This reverts commit 8fa7f667cf61386257c00d6e954855cc3215ae91.

This does not encourage the best practice of describing not just
"what" (i.e. "Revert X" on the title says what we did) but "why"
(i.e. and it does not say why X was undesirable).

We can instead phrase this first line of the body to be more like

    This reverts commit 8fa7f667 (do this and that, 2022-04-25)

so that the title does not have to be

    Revert "do this and that"

We can instead use the title to describe "why" we are reverting the
original commit.

Introduce the "--reference" option to "git revert", and also the
revert.reference configuration variable, which defaults to false, to
tweak the title and the first line of the draft commit message for
when creating a "revert" commit.

When this option is in use, the first line of the pre-filled editor
buffer becomes a comment line that tells the user to say _why_.  If
the user exits the editor without touching this line by mistake,
what we prepare to become the first line of the body, i.e. "This
reverts commit 8fa7f667 (do this and that, 2022-04-25)", ends up to
be the title of the resulting commit.  This behaviour is designed to
help such a user to identify such a revert in "git log --oneline"
easily so that it can be further reworded with "git rebase -i" later.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-26 23:05:03 -07:00
Jeff Hostetler d06055501b fsmonitor--daemon: stub in health thread
Create another thread to watch over the daemon process and
automatically shut it down if necessary.

This commit creates the basic framework for a "health" thread
to monitor the daemon and/or the file system.  Later commits
will add platform-specific code to do the actual work.

The "health" thread is intended to monitor conditions that
would be difficult to track inside the IPC thread pool and/or
the file system listener threads.  For example, when there are
file system events outside of the watched worktree root or if
we want to have an idle-timeout auto-shutdown feature.

This commit creates the health thread itself, defines the thread-proc
and sets up the thread's event loop.  It integrates this new thread
into the existing IPC and Listener thread models.

This commit defines the API to the platform-specific code where all of
the monitoring will actually happen.

The platform-specific code for MacOS is just stubs.  Meaning that the
health thread will immediately exit on MacOS, but that is OK and
expected.  Future work can define MacOS-specific monitoring.

The platform-specific code for Windows sets up enough of the
WaitForMultipleObjects() machinery to watch for system and/or custom
events.  Currently, the set of wait handles only includes our custom
shutdown event (sent from our other theads).  Later commits in this
series will extend the set of wait handles to monitor other
conditions.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-26 15:59:27 -07:00
Jeff Hostetler 207534e423 fsmonitor--daemon: rename listener thread related variables
Rename platform-specific listener thread related variables
and data types as we prepare to add another backend thread
type.

[] `struct fsmonitor_daemon_backend_data` becomes `struct fsm_listen_data`
[] `state->backend_data` becomes `state->listen_data`
[] `state->error_code` becomes `state->listen_error_code`

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-26 15:59:26 -07:00
Jeff Hostetler 802aa31840 fsmonitor--daemon: prepare for adding health thread
Refactor daemon thread startup to make it easier to start
a third thread class to monitor the health of the daemon.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-26 15:59:26 -07:00
Jeff Hostetler 39664e9309 fsmonitor--daemon: cd out of worktree root
Teach the fsmonitor--daemon to CD outside of the worktree
before starting up.

The common Git startup mechanism causes the CWD of the daemon process
to be in the root of the worktree.  On Windows, this causes the daemon
process to hold a locked handle on the CWD and prevents other
processes from moving or deleting the worktree while the daemon is
running.

CD to HOME before entering main event loops.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-26 15:59:26 -07:00
Jeff Hostetler 62a62a2830 fsmonitor-settings: bare repos are incompatible with FSMonitor
Bare repos do not have a worktree, so there is nothing for the
daemon watch.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-26 15:59:26 -07:00
Taylor Blau 5b92477f89 builtin/gc.c: conditionally avoid pruning objects via loose
Expose the new `git repack --cruft` mode from `git gc` via a new opt-in
flag. When invoked like `git gc --cruft`, `git gc` will avoid exploding
unreachable objects as loose ones, and instead create a cruft pack and
`.mtimes` file.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-26 15:48:26 -07:00
Taylor Blau ddee3703b3 builtin/repack.c: add cruft packs to MIDX during geometric repack
When using cruft packs, the following race can occur when a geometric
repack that writes a MIDX bitmap takes place afterwords:

  - First, create an unreachable object and do an all-into-one cruft
    repack which stores that object in the repository's cruft pack.
  - Then make that object reachable.
  - Finally, do a geometric repack and write a MIDX bitmap.

Assuming that we are sufficiently unlucky as to select a commit from the
MIDX which reaches that object for bitmapping, then the `git
multi-pack-index` process will complain that that object is missing.

The reason is because we don't include cruft packs in the MIDX when
doing a geometric repack. Since the "make that object reachable" doesn't
necessarily mean that we'll create a new copy of that object in one of
the packs that will get rolled up as part of a geometric repack, it's
possible that the MIDX won't see any copies of that now-reachable
object.

Of course, it's desirable to avoid including cruft packs in the MIDX
because it causes the MIDX to store a bunch of objects which are likely
to get thrown away. But excluding that pack does open us up to the above
race.

This patch demonstrates the bug, and resolves it by including cruft
packs in the MIDX even when doing a geometric repack.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-26 15:48:26 -07:00
Taylor Blau 72263ffc32 builtin/repack.c: use named flags for existing_packs
We use the `util` pointer for items in the `existing_packs` string list
to indicate which packs are going to be deleted. Since that has so far
been the only use of that `util` pointer, we just set it to 0 or 1.

But we're going to add an additional state to this field in the next
patch, so prepare for that by adding a #define for the first bit so we
can more expressively inspect the flags state.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-26 15:48:26 -07:00
Taylor Blau 4571324b99 builtin/repack.c: allow configuring cruft pack generation
In servers which set the pack.window configuration to a large value, we
can wind up spending quite a lot of time finding new bases when breaking
delta chains between reachable and unreachable objects while generating
a cruft pack.

Introduce a handful of `repack.cruft*` configuration variables to
control the parameters used by pack-objects when generating a cruft
pack.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-26 15:48:26 -07:00
Taylor Blau f9825d1cf7 builtin/repack.c: support generating a cruft pack
Expose a way to split the contents of a repository into a main and cruft
pack when doing an all-into-one repack with `git repack --cruft -d`, and
a complementary configuration variable.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-26 15:48:26 -07:00
Taylor Blau a7d493833f builtin/pack-objects.c: --cruft with expiration
In a previous patch, pack-objects learned how to generate a cruft pack
so long as no objects are dropped.

This patch teaches pack-objects to handle the case where a non-never
`--cruft-expiration` value is passed. This case is slightly more
complicated than before, because we want pack-objects to save
unreachable objects which would have been pruned when there is another
recent (i.e., non-prunable) unreachable object which reaches the other.
We'll call these objects "unreachable but reachable-from-recent".

Here is how pack-objects handles `--cruft-expiration`:

  - Instead of adding all objects outside of the kept pack(s) into the
    packing list, only handle the ones whose mtime is within the grace
    period.

  - Construct a reachability traversal whose tips are the
    unreachable-but-recent objects.

  - Then, walk along that traversal, stopping if we reach an object in
    the kept pack. At each step along the traversal, we add the object
    we are visiting to the packing list.

In the majority of these cases, any object we visit in this traversal
will already be in our packing list. But we will sometimes encounter
reachable-from-recent cruft objects, which we want to retain even if
they aged out of the grace period.

The most subtle point of this process is that we actually don't need to
bother to update the rescued object's mtime. Even though we will write
an .mtimes file with a value that is older than the expiration window,
it will continue to survive cruft repacks so long as any objects which
reach it haven't aged out.

That is, a future repack will also exclude that object from the initial
packing list, only to discover it later on when doing the reachability
traversal.

Finally, stopping early once an object is found in a kept pack is safe
to do because the kept packs ordinarily represent which packs will
survive after repacking. Assuming that it _isn't_ safe to halt a
traversal early would mean that there is some ancestor object which is
missing, which implies repository corruption (i.e., the complete set of
reachable objects isn't present).

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-26 15:48:26 -07:00
Taylor Blau 2fb90409b8 reachable: add options to add_unseen_recent_objects_to_traversal
This function behaves very similarly to what we will need in
pack-objects in order to implement cruft packs with expiration. But it
is lacking a couple of things. Namely, it needs:

  - a mechanism to communicate the timestamps of individual recent
    objects to some external caller

  - and, in the case of packed objects, our future caller will also want
    to know the originating pack, as well as the offset within that pack
    at which the object can be found

  - finally, it needs a way to skip over packs which are marked as kept
    in-core.

To address the first two, add a callback interface in this patch which
reports the time of each recent object, as well as a (packed_git,
off_t) pair for packed objects.

Likewise, add a new option to the packed object iterators to skip over
packs which are marked as kept in core. This option will become
implicitly tested in a future patch.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-26 15:48:26 -07:00
Taylor Blau b757353676 builtin/pack-objects.c: --cruft without expiration
Teach `pack-objects` how to generate a cruft pack when no objects are
dropped (i.e., `--cruft-expiration=never`). Later patches will teach
`pack-objects` how to generate a cruft pack that prunes objects.

When generating a cruft pack which does not prune objects, we want to
collect all unreachable objects into a single pack (noting and updating
their mtimes as we accumulate them). Ordinary use will pass the result
of a `git repack -A` as a kept pack, so when this patch says "kept
pack", readers should think "reachable objects".

Generating a non-expiring cruft packs works as follows:

  - Callers provide a list of every pack they know about, and indicate
    which packs are about to be removed.

  - All packs which are going to be removed (we'll call these the
    redundant ones) are marked as kept in-core.

    Any packs the caller did not mention (but are known to the
    `pack-objects` process) are also marked as kept in-core. Packs not
    mentioned by the caller are assumed to be unknown to them, i.e.,
    they entered the repository after the caller decided which packs
    should be kept and which should be discarded.

    Since we do not want to include objects in these "unknown" packs
    (because we don't know which of their objects are or aren't
    reachable), these are also marked as kept in-core.

  - Then, we enumerate all objects in the repository, and add them to
    our packing list if they do not appear in an in-core kept pack.

This results in a new cruft pack which contains all known objects that
aren't included in the kept packs. When the kept pack is the result of
`git repack -A`, the resulting pack contains all unreachable objects.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-26 15:48:26 -07:00
Taylor Blau fa23090b0c builtin/pack-objects.c: return from create_object_entry()
A new caller in the next commit will want to immediately modify the
object_entry structure created by create_object_entry(). Instead of
forcing that caller to wastefully look-up the entry we just created,
return it from create_object_entry() instead.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-26 15:48:26 -07:00
Taylor Blau 1c573cdd72 pack-write: pass 'struct packing_data' to 'stage_tmp_packfiles'
This structure will be used to communicate the per-object mtimes when
writing a cruft pack. Here, we need the full packing_data structure
because the mtime information is stored in an array there, not on the
individual object_entry's themselves (to avoid paying the overhead in
structure width for operations which do not generate a cruft pack).

We haven't passed this information down before because one of the two
callers (in bulk-checkin.c) does not have a packing_data structure at
all. In that case (where no cruft pack will be generated), NULL is
passed instead.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-26 15:48:26 -07:00
Taylor Blau 94cd775a6c pack-mtimes: support reading .mtimes files
To store the individual mtimes of objects in a cruft pack, introduce a
new `.mtimes` format that can optionally accompany a single pack in the
repository.

The format is defined in Documentation/technical/pack-format.txt, and
stores a 4-byte network order timestamp for each object in name (index)
order.

This patch prepares for cruft packs by defining the `.mtimes` format,
and introducing a basic API that callers can use to read out individual
mtimes.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-26 15:48:26 -07:00
Junio C Hamano 2785b71ef9 Merge branch 'ac/remote-v-with-object-list-filters'
"git remote -v" now shows the list-objects-filter used during
fetching from the remote, if available.

* ac/remote-v-with-object-list-filters:
  builtin/remote.c: teach `-v` to list filters for promisor remotes
2022-05-26 14:51:32 -07:00
Junio C Hamano f49c478f62 Merge branch 'tk/simple-autosetupmerge'
"git -c branch.autosetupmerge=simple branch $A $B" will set the $B
as $A's upstream only when $A and $B shares the same name, and "git
-c push.default=simple" on branch $A would push to update the
branch $A at the remote $B came from.  Also more places use the
sole remote, if exists, before defaulting to 'origin'.

* tk/simple-autosetupmerge:
  push: new config option "push.autoSetupRemote" supports "simple" push
  push: default to single remote even when not named origin
  branch: new autosetupmerge option 'simple' for matching branches
2022-05-26 14:51:30 -07:00
Ævar Arnfjörð Bjarmason 6dd9a91c32 i18n CI: stop allowing non-ASCII source messages in po/git.pot
In the preceding commit we moved away from using xgettext(1) to both
generate the po/git.pot, and to merge the incrementally generated
po/git.pot+ file as we sourced translations from C, shell and Perl.

Doing it this way, which dates back to my initial
implementation[1][2][3] was conflating two things: With xgettext(1)
the --from-code both controls what encoding is specified in the
po/git.pot's header, and what encoding we allow in source messages.

We don't ever want to allow non-ASCII in *source messages*, and doing
so has hid e.g. a buggy message introduced in
a6226fd772 (submodule--helper: convert the bulk of cmd_add() to C,
2021-08-10) from us, we'd warn about it before, but only when running
"make pot", but the operation would still succeed. Now we'll error out
on it when running "make pot".

Since the preceding Makefile changes made this easy: let's add a "make
check-pot" target with the same prerequisites as the "po/git.pot"
target, but without changing the file "po/git.pot". Running it as part
of the "static-analysis" CI target will ensure that we catch any such
issues in the future. E.g.:

    $ make check-pot
        XGETTEXT .build/pot/po/builtin/submodule--helper.c.po
    xgettext: Non-ASCII string at builtin/submodule--helper.c:3381.
              Please specify the source encoding through --from-code.
    make: *** [.build/pot/po/builtin/submodule--helper.c.po] Error 1

1. cd5513a716 (i18n: Makefile: "pot" target to extract messages
   marked for translation, 2011-02-22)
2. adc3b2b276 (Makefile: add xgettext target for *.sh files,
   2011-05-14)
3. 5e9637c629 (i18n: add infrastructure for translating Git with
   gettext, 2011-11-18)

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Jiang Xin <zhiyou.jx@alibaba-inc.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-26 10:30:28 -07:00
Junio C Hamano 3846c2a1ed Merge branch 'tb/receive-pack-code-cleanup'
Code clean-up.

* tb/receive-pack-code-cleanup:
  builtin/receive-pack.c: remove redundant 'if'
2022-05-25 16:42:49 -07:00
Junio C Hamano fa61b7703e Merge branch 'jc/avoid-redundant-submodule-fetch'
"git fetch --recurse-submodules" from multiple remotes (either from
a remote group, or "--all") used to make one extra "git fetch" in
the submodules, which has been corrected.

* jc/avoid-redundant-submodule-fetch:
  fetch: do not run a redundant fetch from submodule
2022-05-25 16:42:49 -07:00
Junio C Hamano 5ed49a75f3 Merge branch 'os/fetch-check-not-current-branch'
The way "git fetch" without "--update-head-ok" ensures that HEAD in
no worktree points at any ref being updated was too wasteful, which
has been optimized a bit.

* os/fetch-check-not-current-branch:
  fetch: limit shared symref check only for local branches
2022-05-25 16:42:48 -07:00
Junio C Hamano 18254f14f2 Merge branch 'jc/show-branch-g-current'
The "--current" option of "git show-branch" should have been made
incompatible with the "--reflog" mode, but this was not enforced,
which has been corrected.

* jc/show-branch-g-current:
  show-branch: -g and --current are incompatible
2022-05-25 16:42:47 -07:00
Taylor Blau 4090511e40 builtin/pack-objects.c: ensure pack validity from MIDX bitmap objects
When using a multi-pack bitmap, pack-objects will try to perform its
traversal using a call to `traverse_bitmap_commit_list()`, which calls
`add_object_entry_from_bitmap()` to add each object it finds to its
packing list.

This path can cause pack-objects to add objects from packs that don't
have open pack_fds on them, by avoiding a call to `is_pack_valid()`.
This is because we only call `is_pack_valid()` on the preferred pack (in
order to do verbatim reuse via `reuse_partial_packfile_from_bitmap()`)
and not others when loading a MIDX bitmap.

In this case, `add_object_entry_from_bitmap()` will check whether it
wants each object entry by calling `want_object_in_pack()`, which will
call `want_found_object` (since its caller already supplied a
`found_pack`). In most cases (particularly without `--local`, and when
`ignored_packed_keep_on_disk` and `ignored_packed_keep_in_core` are
both "0"), we'll take the entry from the pack contained in the MIDX
bitmap, all without an open pack_fd.

When we then try to use that entry later to assemble the actual pack,
we'll be susceptible to any simultaneous writers moving that pack out of
the way (e.g., due to a concurrent repack) without having an open file
descriptor, causing races that result in errors like:

    remote: Enumerating objects: 1498802, done.
    remote: fatal: packfile ./objects/pack/pack-e57d433b5a588daa37fbe946e2b28dfaec03a93e.pack cannot be accessed
    remote: aborting due to possible repository corruption on the remote side.

This race can happen even with multi-pack bitmaps, since we may open a
MIDX bitmap that is being rewritten long before its packs are actually
unlinked.

Work around this by calling `is_pack_valid()` from within
`want_found_object()`, matching the behavior in
`want_object_in_pack_one()` (which has an analogous call). Most calls to
`is_pack_valid()` should be basically no-ops, since only the first call
requires us to open a file (subsequent calls realize the file is already
open, and return immediately).

Importantly, when `want_object_in_pack()` is given a non-NULL
`*found_pack`, but `want_found_object()` rejects the copy of the object
in that pack, we must reset `*found_pack` and `*found_offset` to NULL
and 0, respectively. Failing to do so could lead to other checks in
`want_object_in_pack()` (such as `want_object_in_pack_one()`) using the
same (invalid) pack as `*found_pack`, meaning that we don't call
`is_pack_valid()` because `p == *found_pack`. This can lead the caller
to believe it can use a copy of an object from an invalid pack.

An alternative approach to closing this race would have been to call
`is_pack_valid()` on _all_ packs in a multi-pack bitmap on load. This
has a couple of problems:

  - it is unnecessarily expensive in the cases where we don't actually
    need to open any packs (e.g., in `git rev-list --use-bitmap-index
    --count`)

  - more importantly, it means any time we would have hit this race,
    we'll avoid using bitmaps altogether, leading to significant
    slowdowns by forcing a full object traversal

Co-authored-by: Victoria Dye <vdye@github.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-24 14:27:20 -07:00
Taylor Blau 5045759de8 builtin/pack-objects.c: ensure included --stdin-packs exist
A subsequent patch will teach `want_object_in_pack()` to set its
`*found_pack` and `*found_offset` poitners to NULL when the provided
pack does not pass the `is_pack_valid()` check.

The `--stdin-packs` mode of `pack-objects` is not quite prepared to
handle this. To prepare it for this change, do the following two things:

  - Ensure provided packs pass the `is_pack_valid()` check when
    collecting the caller-provided packs into the "included" and
    "excluded" lists.

  - Gracefully handle any _invalid_ packs being passed to
    `want_object_in_pack()`.

Calling `is_pack_valid()` early on makes it substantially less likely
that we will have to deal with a pack going away, since we'll have an
open file descriptor on its contents much earlier.

But even packs with open descriptors can become invalid in the future if
we (a) hit our open descriptor limit, forcing us to close some open
packs, and (b) one of those just-closed packs has gone away in the
meantime.

`add_object_entry_from_pack()` depends on having a non-NULL
`*found_pack`, since it passes that pointer to `packed_object_info()`,
meaning that we would SEGV if the pointer became NULL (like we propose
to do in `want_object_in_pack()` in the following patch).

But avoiding calling `packed_object_info()` entirely is OK, too, since
its only purpose is to identify which objects in the included packs are
commits, so that they can form the tips of the advisory traversal used
to discover the object namehashes.

Failing to do this means that at worst we will produce lower-quality
deltas, but it does not prevent us from generating the pack as long as
we can find a copy of each object from the disappearing pack in some
other part of the repository.

Co-authored-by: Victoria Dye <vdye@github.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-24 14:27:19 -07:00
Taylor Blau 58a6abb7ba builtin/pack-objects.c: avoid redundant NULL check
Before calling `for_each_object_in_pack()`, the caller
`read_packs_list_from_stdin()` loops through each of the `include_packs`
and checks that its `->util` pointer (which is used to store the `struct
packed_git *` itself) is non-NULL.

This check is redundant, because `read_packs_list_from_stdin()` already
checks that the included packs are non-NULL earlier on in the same
function (and it does not add any new entries in between).

Remove this check, since it is not doing anything in the meantime.

Co-authored-by: Victoria Dye <vdye@github.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-24 14:27:19 -07:00
Junio C Hamano ea78f9ee7a Merge branch 'ab/commit-plug-leaks'
Leakfix in the top-level called-once function.

* ab/commit-plug-leaks:
  commit: fix "author_ident" leak
2022-05-23 14:39:54 -07:00
Derrick Stolee 598b1e7d09 sparse-checkout: integrate with sparse index
When modifying the sparse-checkout definition, the sparse-checkout
builtin calls update_sparsity() to modify the SKIP_WORKTREE bits of all
cache entries in the index. Before, we needed the index to be fully
expanded in order to ensure we had the full list of files necessary that
match the new patterns.

Insert a call to reset_sparse_directories() that expands sparse
directories that are within the new pattern list, but only far enough
that every necessary file path now exists as a cache entry. The
remaining logic within update_sparsity() will modify the SKIP_WORKTREE
bits appropriately.

This allows us to disable command_requires_full_index within the
sparse-checkout builtin. Add tests that demonstrate that we are not
expanding to a full index unnecessarily.

We can see the improved performance in the p2000 test script:

Test                           HEAD~1            HEAD
------------------------------------------------------------------------
2000.24: git ... (sparse-v3)   2.14(1.55+0.58)   1.57(1.03+0.53) -26.6%
2000.25: git ... (sparse-v4)   2.20(1.62+0.57)   1.58(0.98+0.59) -28.2%

These reductions of 26-28% are small compared to most examples, but the
time is dominated by writing a new copy of the base repository to the
worktree and then deleting it again. The fact that the previous index
expansion was such a large portion of the time is telling how important
it is to complete this sparse index integration.

Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-23 11:08:22 -07:00
Derrick Stolee 2d443389fd sparse-checkout: --no-sparse-index needs a full index
When the --no-sparse-index option is supplied, the sparse-checkout
builtin should explicitly ask to expand a sparse index to a full one.
This is currently done implicitly due to the command_requires_full_index
protection, but that will be removed in an upcoming change.

Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-23 11:08:21 -07:00