Commit Graph

71935 Commits (22695a38a4b55322d6399db0e192a57c3a84e541)

Author SHA1 Message Date
Patrick Steinhardt 18c9cb7524 builtin/clone: create the refdb with the correct object format
We're currently creating the reference database with a potentially
incorrect object format when the remote repository's object format is
different from the local default object format. This works just fine for
now because the files backend never records the object format anywhere.
But this logic will fail with any new reference backend that encodes
this information in some form either on-disk or in-memory.

The preceding commits have reshuffled code in git-clone(1) so that there
is no code path that will access the reference database before we have
detected the remote's object format. With these refactorings we can now
defer initialization of the reference database until after we have
learned the remote's object format and thus initialize it with the
correct format from the get-go.

These refactorings are required to make git-clone(1) work with the
upcoming reftable backend when cloning repositories with the SHA256
object format.

This change breaks a test in "t5550-http-fetch-dumb.sh" when cloning an
empty repository with `GIT_TEST_DEFAULT_HASH=sha256`. The test expects
the resulting hash format of the empty cloned repository to match the
default hash, but now we always end up with a sha1 repository. The
problem is that for dumb HTTP fetches, we have no easy way to figure out
the remote's hash function except for deriving it based on the hash
length of refs in `info/refs`. But as the remote repository is empty we
cannot rely on this detection mechanism.

Before the change in this commit we already initialized the repository
with the default hash function and then left it as-is. With this patch
we always use the hash function detected via the remote, where we fall
back to "sha1" in case we cannot detect it.

Neither the old nor the new behaviour are correct as we second-guess the
remote hash function in both cases. But given that this is a rather
unlikely edge case (we use the dumb HTTP protocol, the remote repository
uses SHA256 and the remote repository is empty), let's simply adapt the
test to assert the new behaviour. If we want to properly address this
edge case in the future we will have to extend the dumb HTTP protocol so
that we can properly detect the hash function for empty repositories.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-12 11:16:54 -08:00
Patrick Steinhardt 3c8f60c641 builtin/clone: skip reading HEAD when retrieving remote
After we have set up the remote configuration in git-clone(1) we'll call
`remote_get()` to read the remote from the on-disk configuration. But
next to reading the on-disk configuration, `remote_get()` will also
cause us to try and read the repository's HEAD reference so that we can
figure out the current branch. Besides being pointless in git-clone(1)
because we're operating in an empty repository anyway, this will also
break once we move creation of the reference database to a later point
in time.

Refactor the code to introduce a new `remote_get_early()` function that
will skip reading the HEAD reference to address this issue.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-12 11:16:54 -08:00
Patrick Steinhardt 360822a347 builtin/clone: set up sparse checkout later
When asked to do a sparse checkout, then git-clone(1) will spawn
`git sparse-checkout set` to set up the configuration accordingly. This
requires a proper Git repository or otherwise the command will fail. But
as we are about to move creation of the reference database to a later
point, this prerequisite will not hold anymore.

Move the logic to a later point in time where we know to have created
the reference database already.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-12 11:16:54 -08:00
Patrick Steinhardt 9159029329 builtin/clone: fix bundle URIs with mismatching object formats
We create the reference database in git-clone(1) quite early before
connecting to the remote repository. Given that we do not yet know about
the object format that the remote repository uses at that point in time
the consequence is that the refdb may be initialized with the wrong
object format.

This is not a problem in the context of the files backend as we do not
encode the object format anywhere, and furthermore the only reference
that we write between initializing the refdb and learning about the
object format is the "HEAD" symref. It will become a problem though once
we land the reftable backend, which indeed does require to know about
the proper object format at the time of creation. We thus need to
rearrange the logic in git-clone(1) so that we only initialize the refdb
once we have learned about the actual object format.

As a first step, move listing of remote references to happen earlier,
which also allow us to set up the hash algorithm of the repository
earlier now. While we aim to execute this logic as late as possible
until after most of the setup has happened already, detection of the
object format and thus later the setup of the reference database must
happen before any other logic that may spawn Git commands or otherwise
these Git commands may not recognize the repository as such.

The first Git step where we expect the repository to be fully initalized
is when we fetch bundles via bundle URIs. Funny enough, the comments
there also state that "the_repository must match the cloned repo", which
is indeed not necessarily the case for the hash algorithm right now. So
in practice it is the right thing to detect the remote's object format
before downloading bundle URIs anyway, and not doing so causes clones
with bundle URIs to fail when the local default object format does not
match the remote repository's format.

Unfortunately though, this creates a new issue: downloading bundles may
take a long time, so if we list refs beforehand they might've grown
stale meanwhile. It is not clear how to solve this issue except for a
second reference listing though after we have downloaded the bundles,
which may be an expensive thing to do.

Arguably though, it's preferable to have a staleness issue compared to
being unable to clone a repository altogether.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-12 11:16:54 -08:00
Patrick Steinhardt bab2283ec6 remote-curl: rediscover repository when fetching refs
The reftable format encodes the hash function used by the repository
inside of its tables. The reftable backend thus needs to be initialized
with the correct hash function right from the start, or otherwise we may
end up writing tables with the wrong hash function. But git-clone(1)
initializes the reference database before learning about the hash
function used by the remote repository, which has never been a problem
with the reffiles backend.

To fix this, we'll have to change git-clone(1) to be more careful and
only create the reference backend once it learned about the remote hash
function. This creates a problem for git-remote-curl(1), which will then
be spawned at a time where the repository is not yet fully-initialized.
Consequentially, git-remote-curl(1) will fail to detect the repository,
which eventually causes it to error out once it is asked to fetch remote
objects.

We can address this issue by trying to re-discover the Git repository in
case none was detected at startup time. With this change, the clone will
look as following:

  1. git-clone(1) sets up the initial repository, excluding the
     reference database.

  2. git-clone(1) spawns git-remote-curl(1), which will be unable to
     detect the repository due to a missing "HEAD".

  3. git-clone(1) asks git-remote-curl(1) to list remote references.
     This works just fine as this step does not require a local
     repository

  4. git-clone(1) creates the reference database as it has now learned
     about the hash function.

  5. git-clone(1) asks git-remote-curl(1) to fetch the remote packfile.
     The latter notices that it doesn't have a repository available, but
     it now knows to try and re-discover it.

If the re-discovery succeeds in the last step we can continue with the
clone.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-12 11:16:54 -08:00
Patrick Steinhardt 56cd0334f7 setup: allow skipping creation of the refdb
Allow callers to skip creation of the reference database via a new flag
`INIT_DB_SKIP_REFDB`, which is required for git-clone(1) so that we can
create it at a later point once the object format has been discovered
from the remote repository.

Note that we also uplift the call to `create_reference_database()` into
`init_db()`, which makes it easier to handle the new flag for us. This
changes the order in which we do initialization so that we now set up
the Git configuration before we create the reference database. In
practice this move should not result in any change in behaviour.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-12 11:16:54 -08:00
Patrick Steinhardt 79543e760d setup: extract function to create the refdb
We're about to let callers skip creation of the reference database when
calling `init_db()`. Extract the logic into a standalone function so
that it becomes easier to do this refactoring.

While at it, expand the comment that explains why we always create the
"refs/" directory.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-12 11:16:54 -08:00
Patrick Steinhardt c0cadb0576 reftable/block: reuse buffer to compute record keys
When iterating over entries in the block iterator we compute the key of
each of the entries and write it into a buffer. We do not reuse the
buffer though and thus re-allocate it on every iteration, which is
wasteful.

Refactor the code to reuse the buffer.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-11 07:23:17 -08:00
Patrick Steinhardt a8305bc6d8 reftable/block: introduce macro to initialize `struct block_iter`
There are a bunch of locations where we initialize members of `struct
block_iter`, which makes it harder than necessary to expand this struct
to have additional members. Unify the logic via a new `BLOCK_ITER_INIT`
macro that initializes all members.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-11 07:23:17 -08:00
Patrick Steinhardt 829231dc20 reftable/merged: reuse buffer to compute record keys
When iterating over entries in the merged iterator's queue, we compute
the key of each of the entries and write it into a buffer. We do not
reuse the buffer though and thus re-allocate it on every iteration,
which is wasteful given that we never transfer ownership of the
allocated bytes outside of the loop.

Refactor the code to reuse the buffer. This also fixes a potential
memory leak when `merged_iter_advance_subiter()` returns an error.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-11 07:23:16 -08:00
Patrick Steinhardt 9abda98149 reftable/stack: fix use of unseeded randomness
When writing a new reftable stack, Git will first create the stack with
a random suffix so that concurrent updates will not try to write to the
same file. This random suffix is computed via a call to rand(3P). But we
never seed the function via srand(3P), which means that the suffix is in
fact always the same.

Fix this bug by using `git_rand()` instead, which does not need to be
initialized. While this function is likely going to be slower depending
on the platform, this slowness should not matter in practice as we only
use it when writing a new reftable stack.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-11 07:23:16 -08:00
Patrick Steinhardt 3054fbd93e reftable/stack: fix stale lock when dying
When starting a transaction via `reftable_stack_init_addition()`, we
create a lockfile for the reftable stack itself which we'll write the
new list of tables to. But if we terminate abnormally e.g. via a call to
`die()`, then we do not remove the lockfile. Subsequent executions of
Git which try to modify references will thus fail with an out-of-date
error.

Fix this bug by registering the lock as a `struct tempfile`, which
ensures automatic cleanup for us.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-11 07:23:16 -08:00
Patrick Steinhardt d779996a10 reftable/stack: reuse buffers when reloading stack
In `reftable_stack_reload_once()` we iterate over all the tables added
to the stack in order to figure out whether any of the tables needs to
be reloaded. We use a set of buffers in this context to compute the
paths of these tables, but discard those buffers on every iteration.
This is quite wasteful given that we do not need to transfer ownership
of the allocated buffer outside of the loop.

Refactor the code to instead reuse the buffers to reduce the number of
allocations we need to do. Note that we do not have to manually reset
the buffer because `stack_filename()` does this for us already.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-11 07:23:16 -08:00
Patrick Steinhardt 5c086453ff reftable/stack: perform auto-compaction with transactional interface
Whenever updating references or reflog entries in the reftable stack, we
need to add a new table to the stack, thus growing the stack's length by
one. The stack can grow to become quite long rather quickly, leading to
performance issues when trying to read records. But besides performance
issues, this can also lead to exhaustion of file descriptors very
rapidly as every single table requires a separate descriptor when
opening the stack.

While git-pack-refs(1) fixes this issue for us by merging the tables, it
runs too irregularly to keep the length of the stack within reasonable
limits. This is why the reftable stack has an auto-compaction mechanism:
`reftable_stack_add()` will call `reftable_stack_auto_compact()` after
its added the new table, which will auto-compact the stack as required.

But while this logic works alright for `reftable_stack_add()`, we do not
do the same in `reftable_addition_commit()`, which is the transactional
equivalent to the former function that allows us to write multiple
updates to the stack atomically. Consequentially, we will easily run
into file descriptor exhaustion in code paths that use many separate
transactions like e.g. non-atomic fetches.

Fix this issue by calling `reftable_stack_auto_compact()`.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-11 07:23:16 -08:00
Patrick Steinhardt 15f98b602f reftable/stack: verify that `reftable_stack_add()` uses auto-compaction
While we have several tests that check whether we correctly perform
auto-compaction when manually calling `reftable_stack_auto_compact()`,
we don't have any tests that verify whether `reftable_stack_add()` does
call it automatically. Add one.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-11 07:23:16 -08:00
Patrick Steinhardt 85a8c899ce reftable: handle interrupted writes
There are calls to write(3P) where we don't properly handle interrupts.
Convert them to use `write_in_full()`.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-11 07:23:16 -08:00
Patrick Steinhardt 917a2b3ce9 reftable: handle interrupted reads
There are calls to pread(3P) and read(3P) where we don't properly handle
interrupts. Convert them to use `pread_in_full()` and `read_in_full()`,
respectively.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-11 07:23:16 -08:00
Patrick Steinhardt e32b8ece64 reftable: wrap EXPECT macros in do/while
The `EXPECT` macros used by the reftable test framework are all using a
single `if` statement with the actual condition. This results in weird
syntax when using them in if/else statements like the following:

```
if (foo)
	EXPECT(foo == 2)
else
	EXPECT(bar == 2)
```

Note that there need not be a trailing semicolon. Furthermore, it is not
immediately obvious whether the else now belongs to the `if (foo)` or
whether it belongs to the expanded `if (foo == 2)` from the macro.

Fix this by wrapping the macros in a do/while loop.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-11 07:23:15 -08:00
René Scharfe 7382497372 show-ref: use die_for_incompatible_opt3()
Use the standard message for reporting the use of multiple mutually
exclusive options by calling die_for_incompatible_opt3() instead of
rolling our own.  This has the benefits of showing only the actually
given options, reducing the number of strings to translate and making
the UI slightly more consistent.

Adjust the test to no longer insist on a specific order of the
reported options, as this implementation detail does not affect the
usefulness of the error message.

Reported-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: René Scharfe <l.s.r@web.de>
Reviewed-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-11 07:17:27 -08:00
Junio C Hamano 1a87c842ec Start the 2.44 cycle
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-09 16:37:51 -08:00
Junio C Hamano 1ef1cce9c2 Merge branch 'tz/send-email-negatable-options'
Newer versions of Getopt::Long started giving warnings against our
(ab)use of it in "git send-email".  Bump the minimum version
requirement for Perl to 5.8.1 (from September 2002) to allow
simplifying our implementation.

* tz/send-email-negatable-options:
  send-email: avoid duplicate specification warnings
  perl: bump the required Perl version to 5.8.1 from 5.8.0
2023-12-09 16:37:51 -08:00
Junio C Hamano f8f87e0827 Merge branch 'ak/rebase-autosquash'
"git rebase --autosquash" is now enabled for non-interactive rebase,
but it is still incompatible with the apply backend.

* ak/rebase-autosquash:
  rebase: rewrite --(no-)autosquash documentation
  rebase: support --autosquash without -i
  rebase: fully ignore rebase.autoSquash without -i
2023-12-09 16:37:50 -08:00
Junio C Hamano 98d0a1f93e Merge branch 'vd/for-each-ref-unsorted-optimization'
"git for-each-ref --no-sort" still sorted the refs alphabetically
which paid non-trivial cost.  It has been redefined to show output
in an unspecified order, to allow certain optimizations to take
advantage of.

* vd/for-each-ref-unsorted-optimization:
  t/perf: add perf tests for for-each-ref
  ref-filter.c: use peeled tag for '*' format fields
  for-each-ref: clean up documentation of --format
  ref-filter.c: filter & format refs in the same callback
  ref-filter.c: refactor to create common helper functions
  ref-filter.c: rename 'ref_filter_handler()' to 'filter_one()'
  ref-filter.h: add functions for filter/format & format-only
  ref-filter.h: move contains caches into filter
  ref-filter.h: add max_count and omit_empty to ref_format
  ref-filter.c: really don't sort when using --no-sort
2023-12-09 16:37:50 -08:00
Junio C Hamano e020e55a62 Merge branch 'ps/ban-a-or-o-operator-with-test'
Test and shell scripts clean-up.

* ps/ban-a-or-o-operator-with-test:
  Makefile: stop using `test -o` when unlinking duplicate executables
  contrib/subtree: convert subtree type check to use case statement
  contrib/subtree: stop using `-o` to test for number of args
  global: convert trivial usages of `test <expr> -a/-o <expr>`
2023-12-09 16:37:50 -08:00
Junio C Hamano 4297485172 Merge branch 'ss/format-patch-use-encode-headers-for-cover-letter'
"git format-patch --encode-email-headers" ignored the option when
preparing the cover letter, which has been corrected.

* ss/format-patch-use-encode-headers-for-cover-letter:
  format-patch: fix ignored encode_email_headers for cover letter
2023-12-09 16:37:49 -08:00
Junio C Hamano 340581bcf1 Merge branch 'ps/ref-tests-update'
Update ref-related tests.

* ps/ref-tests-update:
  t: mark several tests that assume the files backend with REFFILES
  t7900: assert the absence of refs via git-for-each-ref(1)
  t7300: assert exact states of repo
  t4207: delete replace references via git-update-ref(1)
  t1450: convert tests to remove worktrees via git-worktree(1)
  t: convert tests to not access reflog via the filesystem
  t: convert tests to not access symrefs via the filesystem
  t: convert tests to not write references via the filesystem
  t: allow skipping expected object ID in `ref-store update-ref`
2023-12-09 16:37:49 -08:00
Junio C Hamano d8b0ec44b1 Merge branch 'jw/git-add-attr-pathspec'
"git add" and "git stash" learned to support the ":(attr:...)"
magic pathspec.

* jw/git-add-attr-pathspec:
  attr: enable attr pathspec magic for git-add and git-stash
2023-12-09 16:37:49 -08:00
Junio C Hamano 34401b7ddb Merge branch 'jk/chunk-bounds-more'
Code clean-up for jk/chunk-bounds topic.

* jk/chunk-bounds-more:
  commit-graph: mark chunk error messages for translation
  commit-graph: drop verify_commit_graph_lite()
  commit-graph: check order while reading fanout chunk
  commit-graph: use fanout value for graph size
  commit-graph: abort as soon as we see a bogus chunk
  commit-graph: clarify missing-chunk error messages
  commit-graph: drop redundant call to "lite" verification
  midx: check consistency of fanout table
  commit-graph: handle overflow in chunk_size checks
2023-12-09 16:37:48 -08:00
Junio C Hamano b4e6618fdf Merge branch 'js/ci-discard-prove-state'
The way CI testing used "prove" could lead to running the test
suite twice needlessly, which has been corrected.

* js/ci-discard-prove-state:
  ci: avoid running the test suite _twice_
2023-12-09 16:37:48 -08:00
Junio C Hamano 14a4445d18 Merge branch 'ps/ci-gitlab'
Add support for GitLab CI.

* ps/ci-gitlab:
  ci: add support for GitLab CI
  ci: install test dependencies for linux-musl
  ci: squelch warnings when testing with unusable Git repo
  ci: unify setup of some environment variables
  ci: split out logic to set up failed test artifacts
  ci: group installation of Docker dependencies
  ci: make grouping setup more generic
  ci: reorder definitions for grouping functions
2023-12-09 16:37:48 -08:00
Junio C Hamano 712177ed04 Merge branch 'js/doc-unit-tests-with-cmake'
Update the base topic to work with CMake builds.

* js/doc-unit-tests-with-cmake:
  cmake: handle also unit tests
  cmake: use test names instead of full paths
  cmake: fix typo in variable name
  artifacts-tar: when including `.dll` files, don't forget the unit-tests
  unit-tests: do show relative file paths
  unit-tests: do not mistake `.pdb` files for being executable
  cmake: also build unit tests
2023-12-09 16:37:47 -08:00
Junio C Hamano 8bf6fbd00d Merge branch 'js/doc-unit-tests'
Process to add some form of low-level unit tests has started.

* js/doc-unit-tests:
  ci: run unit tests in CI
  unit tests: add TAP unit test framework
  unit tests: add a project plan document
2023-12-09 16:37:47 -08:00
Junio C Hamano 0946acfb50 Merge branch 'ps/httpd-tests-on-nixos'
Portability tweak.

* ps/httpd-tests-on-nixos:
  t9164: fix inability to find basename(1) in Subversion hooks
  t/lib-httpd: stop using legacy crypt(3) for authentication
  t/lib-httpd: dynamically detect httpd and modules path
2023-12-09 16:37:47 -08:00
Junio C Hamano 71a1e94821 revision: parse integer arguments to --max-count, --skip, etc., more carefully
The "rev-list" and other commands in the "log" family, being the
oldest part of the system, use their own custom argument parsers,
and integer values of some options are parsed with atoi(), which
allows a non-digit after the number (e.g., "1q") to be silently
ignored.  As a natural consequence, an argument that does not begin
with a digit (e.g., "q") silently becomes zero, too.

Switch to use strtol_i() and parse_timestamp() appropriately to
catch bogus input.

Note that one may naïvely expect that --max-count, --skip, etc., to
only take non-negative values, but we must allow them to also take
negative values, as an escape hatch to countermand a limit set by an
earlier option on the command line; the underlying variables are
initialized to (-1) and "--max-count=-1", for example, is a
legitimate way to reinitialize the limit.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-09 08:57:31 +09:00
Jeff King ea8f9494ab sequencer: simplify away extra git_config_string() call
In our config callback, we call git_config_string() to copy the incoming
value string into a local string. But we don't modify or store that
string; we just look at it and then free it. We can make the code
simpler by just looking at the value passed into the callback.

Note that we do need to check for NULL, which is the one bit of logic
git_config_string() did for us. And I could even see an argument that we
are abstracting any error-checking of the value behind the
git_config_string() layer. But in practice no other callbacks behave
this way; it is standard to check for NULL and then just look at the
string directly.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-09 08:26:23 +09:00
Jeff King 004c9432f7 gpg-interface: drop pointless config_error_nonbool() checks
Config callbacks which use git_config_string() or git_config_pathname()
have no need to check for a NULL value. This is handled automatically
by those helpers.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-09 08:26:22 +09:00
Jeff King 37e8a341ea push: drop confusing configset/callback redundancy
We parse push config by calling git_config() with our git_push_config()
callback. But inside that callback, when we see "push.gpgsign", we
ignore the value passed into the callback and instead make a new call to
git_config_get_value().

This is unnecessary at best, and slightly wrong at worst (if there are
multiple instances, get_value() only returns one; both methods end up
with last-one-wins, but we'd fail to report errors if earlier
incarnations were bogus).

The call was added by 68c757f219 (push: add a config option push.gpgSign
for default signed pushes, 2015-08-19). That commit doesn't give any
reason to deviate from the usual strategy here; it was probably just
somebody unfamiliar with our config API and its conventions.

It also added identical code to builtin/send-pack.c, which also handles
push.gpgsign.

And then the same issue spread to its neighbor in b33a15b081 (push: add
recurseSubmodules config option, 2015-11-17), presumably via
cargo-culting.

This patch fixes all three to just directly use the value provided to
the callback. While I was adjusting the code to do so, I noticed that
push.gpgsign is overly careful about a NULL value. After
git_parse_maybe_bool() has returned anything besides 1, we know that the
value cannot be NULL (if it were, it would be an implicit "true", and
many callers of maybe_bool rely on that). Here that lets us shorten "if
(v && !strcasecmp(v, ...))" to just "if (!strcasecmp(v, ...))".

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-09 08:26:22 +09:00
Jeff King be6bc048d7 config: use git_config_string() for core.checkRoundTripEncoding
Since this code path was recently converted to check for a NULL value,
it now behaves exactly like git_config_string(). We can shorten the code
a bit by using that helper.

Note that git_config_string() takes a const pointer, but our storage
variable is non-const. We're better off making this "const", though,
since the default value points to a string literal (and thus it would be
an error if anybody tried to write to it).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-09 08:26:22 +09:00
Jeff King 0824879078 diff: give more detailed messages for bogus diff.* config
The config callbacks for a few diff.* variables simply return -1 when we
encounter an error. The message you get mentions the offending location,
like:

  fatal: bad config variable 'diff.algorithm' in file '.git/config' at line 7

but is vague about "bad" (as it must be, since the message comes from
the generic config code). Most callbacks add their own messages here, so
let's do the same. E.g.:

  error: unknown value for config 'diff.algorithm': foo
  fatal: bad config variable 'diff.algorithm' in file '.git/config' at line 7

I've written the string in a way that should be reusable for
translators, and matches another similar message in transport.c (there
doesn't yet seem to be a popular generic message to reuse here, so
hopefully this will get the ball rolling).

Note that in the case of diff.algorithm, our parse_algorithm_value()
helper does detect a NULL value string. But it's still worth detecting
it ourselves here, since we can give a more specific error message (and
which is the usual one for unexpected implicit-bool values).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-09 08:26:22 +09:00
Jeff King 92cecce0de config: use config_error_nonbool() instead of custom messages
A few config callbacks use their own custom messages to report an
unexpected implicit bool like:

  [merge "foo"]
  driver

These should just use config_error_nonbool(), so the user sees
consistent messages.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-09 08:26:22 +09:00
Jeff King 0dda4ce9f6 imap-send: don't use git_die_config() inside callback
The point of git_die_config() is to let configset users mention the
file/line info for invalid config, like:

  if (!git_config_get_int("foo.bar", &value)) {
	if (!is_ok(value))
		git_die_config("foo.bar");
  }

Using it from within a config callback is unnecessary, because we can
simply return an error, at which point the config machinery will mention
the file/line of the offending variable. Worse, using git_die_config()
can actually produce the wrong location when the key is found in
multiple spots. For instance, with config like:

  [imap]
  host
  host = foo

we'll report the line number of the "host = foo" line, but the problem
is on the implicit-bool "host" line.

We can fix it by just returning an error code.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-09 08:26:21 +09:00
Jeff King 22e27413ee git_xmerge_config(): prefer error() to die()
When parsing merge config, a few code paths die on error. It's
preferable for us to call error() here, because the resulting error
message from the config parsing code contains much more detail.

For example, before:

  fatal: unknown style 'bogus' given for 'merge.conflictstyle'

and after:

  error: unknown style 'bogus' given for 'merge.conflictstyle'
  fatal: bad config variable 'merge.conflictstyle' in file '.git/config' at line 7

Since we're touching these lines, I also marked them for translation.
There's no reason they shouldn't behave like most other config-parsing
errors.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-09 08:26:21 +09:00
Jeff King 41f98fae02 config: reject bogus values for core.checkstat
If you feed nonsense config like:

  git -c core.checkstat=foobar status

we'll silently ignore the unknown value, rather than reporting an error.
This goes all the way back to c08e4d5b5c (Enable minimal stat checking,
2013-01-22).

Detecting and complaining now is technically a backwards-incompatible
change, but I don't think anybody has any reason to use an invalid value
here. There are no historical values we'd want to allow for backwards
compatibility or anything like that. We are better off loudly telling
the user that their config may not be doing what they expect.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-09 08:26:21 +09:00
Jeff King d49cb162fa fsck: handle NULL value when parsing message config
When parsing fsck.*, receive.fsck.*, or fetch.fsck.*, we don't check for
an implicit bool. So any of:

  [fsck]
  badTree
  [receive "fsck"]
  badTree
  [fetch "fsck"]
  badTree

will cause us to segfault. We can fix it with config_error_nonbool() in
the usual way, but we have to make a few more changes to get good error
messages. The problem is that all three spots do:

  if (skip_prefix(var, "fsck.", &var))

to match and parse the actual message id. But that means that "var" now
just says "badTree" instead of "receive.fsck.badTree", making the
resulting message confusing. We can fix that by storing the parsed
message id in its own separate variable.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-09 08:24:47 +09:00
Jeff King 1b274c9834 trailer: handle NULL value when parsing trailer-specific config
When parsing the "key", "command", and "cmd" trailer config, we just
make a copy of the value string.  If we see an implicit bool like:

  [trailer "foo"]
  key

we'll segfault trying to copy a NULL pointer. We can fix this with the
usual config_error_nonbool() check.

I split this out from the other vanilla cases, because at first glance
it looks like a better fix here would be to move the NULL check out of
the switch statement. But it would change the behavior of other keys
like trailer.*.ifExists, where an implicit bool is interpreted as
EXISTS_DEFAULT.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-09 08:24:47 +09:00
Jeff King 34b1a0d320 submodule: handle NULL value when parsing submodule.*.branch
We record the submodule branch config value as a string, so config that
uses an implicit bool like:

  [submodule "foo"]
  branch

will cause us to segfault. Note that unlike most other config-parsing
bugs of this class, this can be triggered by parsing a bogus .gitmodules
file (which we might do after cloning a malicious repository).

I don't think the security implications are important, though. It's
always a strict NULL dereference, not an out-of-bounds read or write. So
we should reliably kill the process. That may be annoying, but the
impact is limited to the attacker preventing the victim from
successfully using "git clone --recurse-submodules", etc, on the
malicious repo.

The "branch" entry is the only one with this problem; other strings like
"path" and "url" already check for NULL.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-09 08:24:47 +09:00
Jeff King 89086c9466 help: handle NULL value for alias.* config
When showing all config with "git help --all", we print the list of
defined aliases. But our config callback to do so does not check for a
NULL value, meaning a config block like:

  [alias]
  foo

will cause us to segfault. We should detect and complain about this in
the usual way.

Since this command is purely informational (and we aren't trying to run
the alias), we could perhaps just generate a warning and continue. But
this sort of misconfiguration should be pretty rare, and the error
message we will produce points directly to the line of config that needs
to be fixed. So just generating the usual error should be OK.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-09 08:24:47 +09:00
Jeff King 24942ef316 trace2: handle NULL values in tr2_sysenv config callback
If you have config with an implicit bool like:

  [trace2]
  envvars

we'll segfault, as we unconditionally try to xstrdup() the value. We
should instead detect and complain, as a boolean value has no meaning
here. The same is true for every variable in tr2_sysenv_settings (and
this patch covers them all, as we check them in a loop).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-09 08:24:47 +09:00
Jeff King a62712696e setup: handle NULL value when parsing extensions
The "partialclone" extension config records a string, and hence it is an
error to have an implicit bool like:

  [extensions]
  partialclone

in your config. We should recognize and reject this, rather than
segfaulting (which is the current behavior). Note that it's OK to use
config_error_nonbool() here, even though the return value is an enum. We
explicitly document EXTENSION_ERROR as -1 for compatibility with
error(), etc.

This is the only extension value that has this problem. Most of the
others are bools that interpret this value naturally. The exception is
extensions.objectformat, which does correctly check for NULL.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-09 08:24:46 +09:00
Jeff King ba176db511 config: handle NULL value when parsing non-bools
When the config parser sees an "implicit" bool like:

  [core]
  someVariable

it passes NULL to the config callback. Any callback code which expects a
string must check for NULL. This usually happens via helpers like
git_config_string(), etc, but some custom code forgets to do so and will
segfault.

These are all fairly vanilla cases where the solution is just the usual
pattern of:

  if (!value)
        return config_error_nonbool(var);

though note that in a few cases we have to split initializers like:

  int some_var = initializer();

into:

  int some_var;
  if (!value)
        return config_error_nonbool(var);
  some_var = initializer();

There are still some broken instances after this patch, which I'll
address on their own in individual patches after this one.

Reported-by: Carlos Andrés Ramírez Cataño <antaigroupltda@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-12-09 08:24:39 +09:00