Jeff King [Tue, 3 Oct 2023 20:26:09 +0000 (16:26 -0400)]
t6700: mark test as leak-free
This test has never leaked since it was added. Let's annotate it to make
sure it stays that way (and to reduce noise when looking for other
leak-free scripts after we fix some leaks).
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
René Scharfe [Tue, 3 Oct 2023 08:55:21 +0000 (10:55 +0200)]
parse-options: drop unused parse_opt_ctx_t member
5c387428f1 (parse-options: don't emit "ambiguous option" for aliases,
2019-04-29) added "updated_options" to struct parse_opt_ctx_t, but it
has never been used. Remove it.
Signed-off-by: René Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
t1016-compatObjectFormat: add tests to verify the conversion between objects
For now my strategy is simple. Create two identical repositories one
in each format. Use fixed timestamps. Verify the dynamically computed
compatibility objects from one repository match the objects stored in
the other repository.
A general limitation of this strategy is that the git when generating
signed tags and commits with compatObjectFormat enabled will generate
a signature for both formats. To overcome this limitation I have
added "test-tool delete-gpgsig" that when fed an signed commit or tag
with two signatures deletes one of the signatures.
With that in place I can have "git commit" and "git tag" generate
signed objects, have my tool delete one, and feed the new object
into "git hash-object" to create the kinds of commits and tags
git without compatObjectFormat enabled will generate.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Before I extend this test, changing the naming of the relevant
hash from sha1 to oid. Calling the hash sha1 is incorrect today
as it can be either sha1 or sha256 depending on the value of
GIT_DEFAULT_HASH_FUNCTION when the test is called.
I plan to test sha1 and sha256 simultaneously in the same repository.
Having a name like sha1 will be even more confusing.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
test-lib: compute the compatibility hash so tests may use it
Inspired-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
builtin/ls-tree: let the oid determine the output algorithm
Update cmd_ls_tree to call get_oid_with_context and pass
GET_OID_HASH_ANY instead of calling the simpler repo_get_oid.
This implments in ls-tree the behavior that asking to display a sha1
hash displays the corrresponding sha1 encoded object and asking to
display a sha256 hash displayes the corresponding sha256 encoded
object.
This is useful for testing the conversion of an object to an
equivlanet object encoded with a different hash function.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
object-file: handle compat objects in check_object_signature
Update check_object_signature to find the hash algorithm the exising
signature uses, and to use the same hash algorithm when recomputing it
to check the signature is valid.
This will be useful when teaching git ls-tree to display objects
encoded with the compat hash algorithm.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
tree-walk: init_tree_desc take an oid to get the hash algorithm
To make it possible for git ls-tree to display the tree encoded
in the hash algorithm of the oid specified to git ls-tree, update
init_tree_desc to take as a parameter the oid of the tree object.
Update all callers of init_tree_desc and init_tree_desc_gently
to pass the oid of the tree object.
Use the oid of the tree object to discover the hash algorithm
of the oid and store that hash algorithm in struct tree_desc.
Use the hash algorithm in decode_tree_entry and
update_tree_entry_internal to handle reading a tree object encoded in
a hash algorithm that differs from the repositories hash algorithm.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
builtin/cat-file: let the oid determine the output algorithm
Use GET_OID_HASH_ANY when calling get_oid_with_context. This
implements the semi-obvious behaviour that specifying a sha1 oid shows
the output for a sha1 encoded object, and specifying a sha256 oid
shows the output for a sha256 encoded object.
This is useful for testing the the conversion of an object to an
equivalent object encoded with a different hash function.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
object-file: update object_info_extended to reencode objects
oid_object_info_extended is updated to detect an oid encoding that
does not match the current repository, use repo_oid_to_algop to find
the correspoding oid in the current repository and to return the data
for the oid.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
object-file-convert: convert commits that embed signed tags
As mentioned in the hash function transition plan commit mergetag
lines need to be handled. The commit mergetag lines embed an entire
tag object in a commit object.
Keep the implementation sane if not fast by unembedding the tag
object, converting the tag object, and embedding the new tag object,
in the new commit object.
In the long run I don't expect any other approach is maintainable, as
tag objects may be extended in ways that require additional
translation.
To keep the implementation of convert_commit_object maintainable I
have modified convert_commit_object to process the lines in any order,
and to fail on unknown lines. We can't know ahead of time if a new
line might embed something that needs translation or not so it is
better to fail and require the code to be updated instead of silently
mistranslating objects.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
object-file-convert: convert commit objects when writing
When writing a commit object in a repository with both SHA-1 and
SHA-256, we'll need to convert our commit objects so that we can write
the hash values for both into the repository. To do so, let's add a
function to convert commit objects.
Read the commit object and map the tree value and any of the parent
values, and copy the rest of the commit through unmodified. Note that
we don't need to modify the signature headers, because they are the
same under both algorithms.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
object-file-convert: convert tag objects when writing
When writing a tag object in a repository with both SHA-1 and SHA-256,
we'll need to convert our commit objects so that we can write the hash
values for both into the repository. To do so, let's add a function to
convert tag objects.
Note that signatures for tag objects in the current algorithm trail the
message, and those for the alternate algorithm are in headers.
Therefore, we parse the tag object for both a trailing signature and a
header and then, when writing the other format, swap the two around.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
object-file-convert: add a function to convert trees between algorithms
In the future, we're going to want to provide SHA-256 repositories that
have compatibility support for SHA-1 as well. In order to do so, we'll
need to be able to convert tree objects from SHA-256 to SHA-1 by writing
a tree with each SHA-256 object ID mapped to a SHA-1 object ID.
We implement a function, convert_tree_object, that takes an existing
tree buffer and writes it to a new strbuf, converting between
algorithms. Let's make this function generic, because while we only
need it to convert from the main algorithm to the compatibility
algorithm now, we may need to do the other way around in the future,
such as for transport.
We avoid reusing the code in decode_tree_entry because that code
normalizes data, and we don't want that here. We want to produce a
complete round trip of data, so if, for example, the old entry had a
wrongly zero-padded mode, we'd want to preserve that when converting to
ensure a stable hash value.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
object: factor out parse_mode out of fast-import and tree-walk into in object.h
builtin/fast-import.c and tree-walk.c have almost identical version of
get_mode. The two functions started out the same but have diverged
slightly. The version in fast-import changed mode to a uint16_t to
save memory. The version in tree-walk started erroring if no mode was
present.
As far as I can tell both of these changes are valid for both of the
callers, so add the both changes and place the common parsing helper
in object.h
Rename the helper from get_mode to parse_mode so it does not
conflict with another helper named get_mode in diff-no-index.c
This will be used shortly in a new helper decode_tree_entry_raw
which is used to compute cmpatibility objects as part of
the sha256 transition.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
cache: add a function to read an OID of a specific algorithm
Currently, we always read a object ID of the current algorithm with
oidread. However, once we start converting objects, we'll need to
consider what happens when we want to read an object ID of a specific
algorithm, such as the compatibility algorithm. To make this easier,
let's define oidread_algop, which specifies which algorithm we should
use for our object ID, and define oidread in terms of it.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we write a tag the object oid is specific to the hash algorithm.
This matters when a tag is signed. The hash transition plan calls for
signatures on both the sha1 form and the sha256 form of the object,
and for both of those signatures to live in the tag object.
To generate tag object with multiple signatures, first compute the
unsigned form of the tag, and then if the tag is being signed compute
the unsigned form of the tag with the compatibilityr hash. Then
compute compute the signatures of both buffers.
Once the signatures are computed add them to both buffers. This
allows computing the compatibility hash in do_sign, saving
write_object_file the expense of recomputing the compatibility tag
just to compute it's hash.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
commit: export add_header_signature to support handling signatures on tags
Rename add_commit_signature as add_header_signature, and expose it so
that it can be used for converting tags from one object format to
another.
Inspired-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
commit: convert mergetag before computing the signature of a commit
It so happens that commit mergetag lines embed a tag object. So to
compute the compatible signature of a commit object that has mergetag
lines the compatible embedded tag must be computed first.
Implement this by duplicating and converting the commit extra headers
into the compatible version of the commit extra headers, that need
to be passed to commit_tree_extended.
To handle merge tags only the compatible extra headers need to be
computed.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we write a commit, we include data that is specific to the hash
algorithm, such as parents and the root tree. In order to write both a
SHA-1 commit and a SHA-256 version, we need to convert between them.
However, a straightforward conversion isn't necessarily what we want.
When we sign a commit, we sign its data, so if we create a commit for
SHA-256 and then write a SHA-1 version, we'll still have only signed the
SHA-256 data. While this is valid, it would be better to sign both
forms of data so people using SHA-1 can verify the signatures as well.
Consequently, we don't want to use the standard mapping that occurs when
we write an object. Instead, let's move most of the writing of the
commit into a separate function which is agnostic of the hash algorithm
and which simply writes into a buffer and specify both versions of the
object ourselves.
We can then call this function twice: once with the SHA-256 contents,
and if SHA-1 is enabled, once with the SHA-1 contents. If we're signing
the commit, we then sign both versions and append both signatures to
both buffers. To produce a consistent hash, we always append the
signatures in the order in which Git implemented them: first SHA-1, then
SHA-256.
In order to make this signing code work, we split the commit signing
code into two functions, one which signs the buffer, and one which
appends the signature.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
object-file: add a compat_oid_in parameter to write_object_file_flags
To create the proper signatures for commit objects both versions of
the commit object need to be generated and signed. After that it is
a waste to throw away the work of generating the compatibility hash
so update write_object_file_flags to take a compatibility hash input
parameter that it can use to skip the work of generating the
compatability hash.
Update the places that don't generate the compatability hash to
pass NULL so it is easy to tell write_object_file_flags should
not attempt to use their compatability hash.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
object-file: update the loose object map when writing loose objects
To implement SHA1 compatibility on SHA256 repositories the loose
object map needs to be updated whenver a loose object is written.
Updating the loose object map this way allows git to support
the old hash algorithm in constant time.
The functions write_loose_object, and stream_loose_object are
the only two functions that write to the loose object store.
Update stream_loose_object to compute the compatibiilty hash, update
the loose object, and then call repo_add_loose_object_map to update
the loose object map.
Update write_object_file_flags to convert the object into
it's compatibility encoding, hash the compatibility encoding,
write the object, and then update the loose object map.
Update force_object_loose to lookup the hash of the compatibility
encoding, write the loose object, and then update the loose object
map.
Update write_object_file_literally to convert the object into it's
compatibility hash encoding, hash the compatibility enconding, write
the object, and then update the loose object map, when the type string
is a known type. For objects with an unknown type this results in a
partially broken repository, as the objects are not mapped.
The point of write_object_file_literally is to generate a partially
broken repository for testing. For testing skipping writing the loose
object map is much more useful than refusing to write the broken
object at all.
Except that the loose objects are updated before the loose object map
I have not done any analysis to see how robust this scheme is in the
event of failure.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Update loose_objects_cache when udpating the loose objects map. This
oidtree is used to discover which oids are possibilities when
resolving short names, and it can support a mixture of sha1
and sha256 oids.
With this any oid recorded objects/loose-objects-idx is usable
for resolving an oid to an object.
To make this maintainable a helper insert_loose_map is factored
out of load_one_loose_object_map and repo_add_loose_object_map,
and then modified to also update the loose_objects_cache.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
loose: add a mapping between SHA-1 and SHA-256 for loose objects
As part of the transition plan, we'd like to add a file in the .git
directory that maps loose objects between SHA-1 and SHA-256. Let's
implement the specification in the transition plan and store this data
on a per-repository basis in struct repository.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
We currently have support for using a full stage 4 SHA-256
implementation. However, we'd like to support interoperability with
SHA-1 repositories as well. The transition plan anticipates a
compatibility hash algorithm configuration option that we can use to
implement support for this. Let's add an element to the repository
structure that indicates the compatibility hash algorithm so we can use
it when we need to consider interoperability between algorithms.
Add a helper function repo_set_compat_hash_algo that takes a
compatibility hash algorithm and sets "repo->compat_hash_algo". If
GIT_HASH_UNKNOWN is passed as the compatibility hash algorithm
"repo->compat_hash_algo" is set to NULL.
For now, the code results in "repo->compat_hash_algo" always being set
to NULL, but that will change once a configuration option is added.
Inspired-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
object-names: support input of oids in any supported hash
Support short oids encoded in any algorithm, while ensuring enough of
the oid is specified to disambiguate between all of the oids in the
repository encoded in any algorithm.
By default have the code continue to only accept oids specified in the
storage hash algorithm of the repository, but when something is
ambiguous display all of the possible oids from any accepted oid
encoding.
A new flag is added GET_OID_HASH_ANY that when supplied causes the
code to accept oids specified in any hash algorithm, and to return the
oids that were resolved.
This implements the functionality that allows both SHA-1 and SHA-256
object names, from the "Object names on the command line" section of
the hash function transition document.
Care is taken in get_short_oid so that when the result is ambiguous
the output remains the same if GIT_OID_HASH_ANY was not supplied. If
GET_OID_HASH_ANY was supplied objects of any hash algorithm that match
the prefix are displayed.
This required updating repo_for_each_abbrev to give it a parameter so
that it knows to look at all hash algorithms.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
oid-array: teach oid-array to handle multiple kinds of oids
While looking at how to handle input of both SHA-1 and SHA-256 oids in
get_oid_with_context, I realized that the oid_array in
repo_for_each_abbrev might have more than one kind of oid stored in it
simultaneously.
Update to oid_array_append to ensure that oids added to an oid array
always have an algorithm set.
Update void_hashcmp to first verify two oids use the same hash algorithm
before comparing them to each other.
With that oid-array should be safe to use with different kinds of
oids simultaneously.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
object-file-convert: stubs for converting from one object format to another
Two basic functions are provided:
- convert_object_file Takes an object file it's type and hash algorithm
and converts it into the equivalent object file that would
have been generated with hash algorithm "to".
For blob objects there is no conversation to be done and it is an
error to use this function on them.
For commit, tree, and tag objects embedded oids are replaced by the
oids of the objects they refer to with those objects and their
object ids reencoded in with the hash algorithm "to". Signatures
are rearranged so that they remain valid after the object has
been reencoded.
- repo_oid_to_algop which takes an oid that refers to an object file
and returns the oid of the equivalent object file generated
with the target hash algorithm.
The pair of files object-file-convert.c and object-file-convert.h are
introduced to hold as much of this logic as possible to keep this
conversion logic cleanly separated from everything else and in the
hopes that someday the code will be clean enough git can support
compiling out support for sha1 and the various conversion functions.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
A previous commit implemented the `gc.repackFilter` config option
to specify a filter that should be used by `git gc` when
performing repacks.
Another previous commit has implemented
`git repack --filter-to=<dir>` to specify the location of the
packfile containing filtered out objects when using a filter.
Let's implement the `gc.repackFilterTo` config option to specify
that location in the config when `gc.repackFilter` is used.
Now when `git gc` will perform a repack with a <dir> configured
through this option and not empty, the repack process will be
passed a corresponding `--filter-to=<dir>` argument.
Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
repack: implement `--filter-to` for storing filtered out objects
A previous commit has implemented `git repack --filter=<filter-spec>` to
allow users to filter out some objects from the main pack and move them
into a new different pack.
It would be nice if this new different pack could be created in a
different directory than the regular pack. This would make it possible
to move large blobs into a pack on a different kind of storage, for
example cheaper storage.
Even in a different directory, this pack can be accessible if, for
example, the Git alternates mechanism is used to point to it. In fact
not using the Git alternates mechanism can corrupt a repo as the
generated pack containing the filtered objects might not be accessible
from the repo any more. So setting up the Git alternates mechanism
should be done before using this feature if the user wants the repo to
be fully usable while this feature is used.
In some cases, like when a repo has just been cloned or when there is no
other activity in the repo, it's Ok to setup the Git alternates
mechanism afterwards though. It's also Ok to just inspect the generated
packfile containing the filtered objects and then just move it into the
'.git/objects/pack/' directory manually. That's why it's not necessary
for this command to check that the Git alternates mechanism has been
already setup.
While at it, as an example to show that `--filter` and `--filter-to`
work well with other options, let's also add a test to check that these
options work well with `--max-pack-size`.
Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
A previous commit has implemented `git repack --filter=<filter-spec>` to
allow users to filter out some objects from the main pack and move them
into a new different pack.
Users might want to perform such a cleanup regularly at the same time as
they perform other repacks and cleanups, so as part of `git gc`.
Let's allow them to configure a <filter-spec> for that purpose using a
new gc.repackFilter config option.
Now when `git gc` will perform a repack with a <filter-spec> configured
through this option and not empty, the repack process will be passed a
corresponding `--filter=<filter-spec>` argument.
Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
This new option puts the objects specified by `<filter-spec>` into a
separate packfile.
This could be useful if, for example, some blobs take up a lot of
precious space on fast storage while they are rarely accessed. It could
make sense to move them into a separate cheaper, though slower, storage.
It's possible to find which new packfile contains the filtered out
objects using one of the following:
- `git verify-pack -v ...`,
- `test-tool find-pack ...`, which a previous commit added,
- `--filter-to=<dir>`, which a following commit will add to specify
where the pack containing the filtered out objects will be.
This feature is implemented by running `git pack-objects` twice in a
row. The first command is run with `--filter=<filter-spec>`, using the
specified filter. It packs objects while omitting the objects specified
by the filter. Then another `git pack-objects` command is launched using
`--stdin-packs`. We pass it all the previously existing packs into its
stdin, so that it will pack all the objects in the previously existing
packs. But we also pass into its stdin, the pack created by the previous
`git pack-objects --filter=<filter-spec>` command as well as the kept
packs, all prefixed with '^', so that the objects in these packs will be
omitted from the resulting pack. The result is that only the objects
filtered out by the first `git pack-objects` command are in the pack
resulting from the second `git pack-objects` command.
As the interactions with kept packs are a bit tricky, a few related
tests are added.
Helped-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: John Cai <johncai86@gmail.com> Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
pack-bitmap-write: rebuild using new bitmap when remapping
`git repack` is about to learn a new `--filter=<filter-spec>` option and
we will want to check that this option is incompatible with
`--write-bitmap-index`.
Unfortunately it appears that a test like:
test_expect_success '--filter fails with --write-bitmap-index' '
test_must_fail \
env GIT_TEST_MULTI_PACK_INDEX_WRITE_BITMAP=0 \
git -C bare.git repack -a -d --write-bitmap-index --filter=blob:none
'
sometimes fail because when rebuilding bitmaps, it appears that we are
reusing existing bitmap information. So instead of detecting that some
objects are missing and erroring out as it should, the
`git repack --write-bitmap-index --filter=...` command succeeds.
Let's fix that by making sure we rebuild bitmaps using new bitmaps
instead of existing ones.
Helped-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Create a new find_pack_prefix() to refactor code that handles finding
the pack prefix from the packtmp and packdir global variables, as we are
going to need this feature again in following commit.
Signed-off-by: Christian Couder <chriscool@tuxfamily.org Signed-off-by: Junio C Hamano <gitster@pobox.com>
Create a new finish_pack_objects_cmd() to refactor duplicated code
that handles reading the packfile names from the output of a
`git pack-objects` command and putting it into a string_list, as well as
calling finish_command().
While at it, beautify a code comment a bit in the new function.
Signed-off-by: Christian Couder <chriscool@tuxfamily.org Signed-off-by: Junio C Hamano <gitster@pobox.com>
9535ce7337 (pack-objects: add list-objects filtering, 2017-11-21)
taught `git pack-objects` to use `--filter`, but required the use of
`--stdout` since a partial clone mechanism was not yet in place to
handle missing objects. Since then, changes like 9e27beaa23
(promisor-remote: implement promisor_remote_get_direct(), 2019-06-25)
and others added support to dynamically fetch objects that were missing.
Even without a promisor remote, filtering out objects can also be useful
if we can put the filtered out objects in a separate pack, and in this
case it also makes sense for pack-objects to write the packfile directly
to an actual file rather than on stdout.
Remove the `--stdout` requirement when using `--filter`, so that in a
follow-up commit, repack can pass `--filter` to pack-objects to omit
certain objects from the resulting packfile.
Signed-off-by: John Cai <johncai86@gmail.com> Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Alyssa Ross [Sun, 1 Oct 2023 15:18:45 +0000 (15:18 +0000)]
diff: fix --merge-base with annotated tags
Checking early for OBJ_COMMIT excludes other objects that can be
resolved to commits, like annotated tags. If we remove it, annotated
tags will be resolved and handled just fine by
lookup_commit_reference(), and if we are given something that can't be
resolved to a commit, we'll still get a useful error message, e.g.:
Junio C Hamano [Mon, 2 Oct 2023 18:20:00 +0000 (11:20 -0700)]
Merge branch 'jc/unresolve-removal'
"checkout --merge -- path" and "update-index --unresolve path" did
not resurrect conflicted state that was resolved to remove path,
but now they do.
* jc/unresolve-removal:
checkout: allow "checkout -m path" to unmerge removed paths
checkout/restore: add basic tests for --merge
checkout/restore: refuse unmerging paths unless checking out of the index
update-index: remove stale fallback code for "--unresolve"
update-index: use unmerge_index_entry() to support removal
resolve-undo: allow resurrecting conflicted state that resolved to deletion
update-index: do not read HEAD and MERGE_HEAD unconditionally
diff --stat: set the width defaults in a helper function
Extract the commonly used initialization of the --stat-width=<width>,
--stat-name-width=<width> and --stat-graph-with=<width> parameters to their
internal default values into a helper function, to avoid repeating the same
initialization code in a few places.
Add a couple of tests to additionally cover existing configuration options
diff.statNameWidth=<width> and diff.statGraphWidth=<width> when used by
git-merge to generate --stat outputs. This closes the gap that existed
previously in the --stat tests, and reduces the chances for having any
regressions introduced by this commit.
While there, perform a small bunch of minor wording tweaks in the improved
unit test, to improve its test-level consistency a bit.
Signed-off-by: Dragan Simic <dsimic@manjaro.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Calvin Wan [Fri, 29 Sep 2023 21:20:51 +0000 (14:20 -0700)]
parse: separate out parsing functions from config.h
The files config.{h,c} contain functions that have to do with parsing,
but not config.
In order to further reduce all-in-one headers, separate out functions in
config.c that do not operate on config into its own file, parse.h,
and update the include directives in the .c files that need only such
functions accordingly.
Signed-off-by: Calvin Wan <calvinwan@google.com> Signed-off-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Calvin Wan [Fri, 29 Sep 2023 21:20:50 +0000 (14:20 -0700)]
config: correct bad boolean env value error message
An incorrectly defined boolean environment value would result in the
following error message:
bad boolean config value '%s' for '%s'
This is a misnomer since environment value != config value. Instead of
calling git_config_bool() to parse the environment value, mimic the
functionality inside of git_config_bool() but with the correct error
message.
Signed-off-by: Calvin Wan <calvinwan@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Calvin Wan [Fri, 29 Sep 2023 21:20:49 +0000 (14:20 -0700)]
wrapper: reduce scope of remove_or_warn()
remove_or_warn() is only used by entry.c and apply.c, but it is
currently declared and defined in wrapper.{h,c}, so it has a scope much
greater than it needs. This needlessly large scope also causes wrapper.c
to need to include object.h, when this file is largely unconcerned with
Git objects.
Move remove_or_warn() to entry.{h,c}. The file apply.c still has access
to it, since it already includes entry.h for another reason.
Signed-off-by: Calvin Wan <calvinwan@google.com> Signed-off-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Calvin Wan [Fri, 29 Sep 2023 21:20:48 +0000 (14:20 -0700)]
hex-ll: separate out non-hash-algo functions
In order to further reduce all-in-one headers, separate out functions in
hex.h that do not operate on object hashes into its own file, hex-ll.h,
and update the include directives in the .c files that need only such
functions accordingly.
Signed-off-by: Calvin Wan <calvinwan@google.com> Signed-off-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano [Fri, 29 Sep 2023 16:04:15 +0000 (09:04 -0700)]
Merge branch 'jc/alias-completion'
The command line completion script (in contrib/) can be told to
complete aliases by including ": git <cmd> ;" in the alias to tell
it that the alias should be completed similar to how "git <cmd>" is
completed. The parsing code for the alias as been loosened to
allow ';' without an extra space before it.
* jc/alias-completion:
completion: loosen and document the requirement around completing alias
Junio C Hamano [Fri, 29 Sep 2023 16:04:14 +0000 (09:04 -0700)]
Merge branch 'jk/fsmonitor-unused-parameter'
Unused parameters in fsmonitor related code paths have been marked
as such.
* jk/fsmonitor-unused-parameter:
run-command: mark unused parameters in start_bg_wait callbacks
fsmonitor: mark unused hashmap callback parameters
fsmonitor/darwin: mark unused parameters in system callback
fsmonitor: mark unused parameters in stub functions
fsmonitor/win32: mark unused parameter in fsm_os__incompatible()
fsmonitor: mark some maybe-unused parameters
fsmonitor/win32: drop unused parameters
fsmonitor: prefer repo_git_path() to git_pathdup()
The soft limit of the first line of the commit message should be
"no more than 50 characters" or "50 characters or less", but not
"less than 50 character".
Signed-off-by: 谢致邦 (XIE Zhibang) <Yeking@Red54.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King [Thu, 28 Sep 2023 04:39:51 +0000 (00:39 -0400)]
commit-graph: report incomplete chains during verification
The load_commit_graph_chain_fd_st() function will stop loading chains
when it sees an error. But if it has loaded any graph slice at all, it
will return it. This is a good thing for normal use (we use what data we
can, and this is just an optimization). But it's a bad thing for
"commit-graph verify", which should be careful about finding any
irregularities. We do complain to stderr with a warning(), but the
verify command still exits with a successful return code.
The new tests here cover corruption of both the base and tip slices of
the chain. The corruption of the base file already works (it is the
first file we look at, so when we see the error we return NULL). The
"tip" case is what is fixed by this patch (it complains to stderr but
still returns the base slice).
Likewise the existing tests for corruption of the commit-graph-chain
file itself need to be updated. We already exited non-zero correctly for
the "base" case, but the "tip" case can now do so, too.
Note that this also causes us to adjust a test later in the file that
similarly corrupts a tip (though confusingly the test script calls this
"base"). It checks stderr but erroneously expects the whole "verify"
command to exit with a successful code.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King [Thu, 28 Sep 2023 04:39:10 +0000 (00:39 -0400)]
commit-graph: tighten chain size check
When we open a commit-graph-chain file, if it's smaller than a single
entry, we just quietly treat that as ENOENT. That make some sense if the
file is truly zero bytes, but it means that "commit-graph verify" will
quietly ignore a file that contains garbage if that garbage happens to
be short.
Instead, let's only simulate ENOENT when the file is truly empty, and
otherwise return EINVAL. The normal graph-loading routines don't care,
but "commit-graph verify" will notice and complain about the difference.
It's not entirely clear to me that the 0-is-ENOENT case actually happens
in real life, so we could perhaps just eliminate this special-case
altogether. But this is how we've always behaved, so I'm preserving it
in the name of backwards compatibility (though again, it really only
matters for "verify", as the regular routines are happy to load what
they can).
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King [Thu, 28 Sep 2023 04:38:59 +0000 (00:38 -0400)]
commit-graph: detect read errors when verifying graph chain
Because it's OK to not have a graph file at all, the graph_verify()
function needs to tell the difference between a missing file and a real
error. So when loading a traditional graph file, we call
open_commit_graph() separately from load_commit_graph_chain_fd_st(), and
don't complain if the first one fails with ENOENT.
When the function learned about chain files in 3da4b609bb (commit-graph:
verify chains with --shallow mode, 2019-06-18), we couldn't be as
careful, since the only way to load a chain was with
read_commit_graph_one(), which did both the open/load as a single unit.
So we'll miss errors in chain files we load, thinking instead that there
was just no chain file at all.
Note that we do still report some of these problems to stderr, as the
loading function calls error() and warning(). But we'd exit with a
successful exit code, which is wrong.
We can fix that by using the recently split open/load functions for
chains. That lets us treat the chain file just like a single file with
respect to error handling here.
An existing test (from 3da4b609bb) shows off the problem; we were
expecting "commit-graph verify" to report success, but that makes no
sense. We did not even verify the contents of the graph data, because we
couldn't load it! I don't think this was an intentional exception, but
rather just the test covering what happened to occur.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
In t5324.20, we corrupt a hex character 60 bytes into the graph chain
file. Since the file consists of two hash identifiers, one per line, the
corruption differs between sha1 and sha256. In a sha1 repository, the
corruption is on the second line, and in a sha256 repository, it is on
the first.
We should of course detect the problem with either line. But as the next
few patches will show (and fix), that is not the case (in fact, we
currently do not exit non-zero for either line!). And while at the end
of our series we'll catch all errors, our intermediate states will have
differing behavior between the two hashes.
Let's make sure we test corruption of both the first and second lines,
and do so consistently with either hash by choosing offsets which are
always in the first hash (30 bytes) or in the second (70).
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King [Thu, 28 Sep 2023 04:38:17 +0000 (00:38 -0400)]
commit-graph: check mixed generation validation when loading chain file
In read_commit_graph_one(), we call validate_mixed_generation_chain()
after loading the graph. Even though we don't check the return value,
this has the side effect of clearing the read_generation_data flag,
which is important when working with mixed generation numbers.
But doing this in load_commit_graph_chain_fd_st() makes more sense:
1. We are calling it even when we did not load a chain at all, which
is pointless (you cannot have mixed generations in a single file).
2. For now, all callers load the graph via read_commit_graph_one().
But the point of factoring out the open/load in the previous commit
was to let "commit-graph verify" call them separately. So it needs
to trigger this function as part of the load.
Without this patch, the mixed-generation tests in t5324 would start
failing on "git commit-graph verify" calls, once we switch to using
a separate open/load call there.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King [Thu, 28 Sep 2023 04:38:07 +0000 (00:38 -0400)]
commit-graph: factor out chain opening function
The load_commit_graph_chain() function opens the chain file and all of
the slices of graph that it points to. If there is no chain file (which
is a totally normal condition), we return NULL. But if we run into
errors with the chain file or loading the actual graph data, we also
return NULL, and the caller cannot tell the difference.
The caller can check for ENOENT for the unremarkable "no such file"
case. But I'm hesitant to assume that the rest of the function would
never accidentally set errno to ENOENT itself, since it is opening the
slice files (and that would mean the caller fails to notice a real
error).
So let's break this into two functions: one to open the file, and one to
actually load it. This matches the interface we provide for the
non-chain graph file, which will also come in handy in a moment when we
fix some bugs in the "git commit-graph verify" code.
Some notes:
- I've kept the "1 is good, 0 is bad" return convention (and the weird
"fd" out-parameter) used by the matching open_commit_graph()
function and other parts of the commit-graph code. This is unlike
most of the rest of Git (which would just return the fd, with -1 for
error), but it makes sense to stay consistent with the adjacent bits
of the API here.
- The existing chain loading function will quietly return if the file
is too small to hold a single entry. I've retained that behavior
(and explicitly set ENOENT in the opener function) for now, under
the notion that it's probably valid (though I'd imagine unusual) to
have an empty chain file.
There are two small behavior changes here, but I think both are strictly
positive:
1. The original blindly did a stat() before checking if fopen()
succeeded, meaning we were making a pointless extra stat call.
2. We now use fstat() to check the file size. The previous code using
a regular stat() on the pathname meant we could technically race
with somebody updating the chain file, and end up with a size that
does not match what we just opened with fopen(). I doubt anybody
ever hit this in practice, but it may have caused an out-of-bounds
read.
We'll retain the load_commit_graph_chain() function which does both the
open and reading steps (most existing callers do not care about seeing
errors anyway, since loading commit-graphs is optimistic).
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
bulk-checkin: only support blobs in index_bulk_checkin
As the code is written today index_bulk_checkin only accepts blobs.
Remove the enum object_type parameter and rename index_bulk_checkin to
index_blob_bulk_checkin, index_stream to index_blob_stream,
deflate_to_pack to deflate_blob_to_pack, stream_to_pack to
stream_blob_to_pack, to make this explicit.
Not supporting commits, tags, or trees has no downside as it is not
currently supported now, and commits, tags, and trees being smaller by
design do not have the problem that the problem that index_bulk_checkin
was built to solve.
Before we start adding code to support the hash function transition
supporting additional objects types in index_bulk_checkin has no real
additional cost, just an extra function parameter to know what the
object type is. Once we begin the hash function transition this is not
the case.
The hash function transition document specifies that a repository with
compatObjectFormat enabled will compute and store both the SHA-1 and
SHA-256 hash of every object in the repository.
What makes this a challenge is that it is not just an additional hash
over the same object. Instead the hash function transition document
specifies that the compatibility hash (specified with
compatObjectFormat) be computed over the equivalent object that another
git repository whose storage hash (specified with objectFormat) would
store. When comparing equivalent repositories built with different
storage hash functions, the oids embedded in objects used to refer to
other objects differ and the location of signatures within objects
differ.
As blob objects have neither oids referring to other objects nor stored
signatures their storage hash and their compatibility hash are computed
over the same object.
The other kinds of objects: trees, commits, and tags, all store oids
referring to other objects. Signatures are stored in commit and tag
objects. As oids and the tags to store signatures are not the same size
in repositories built with different storage hashes the size of the
equivalent objects are also different.
A version of index_bulk_checkin that supports more than just blobs when
computing both the SHA-1 and the SHA-256 of every object added would
need a different, and more expensive structure. The structure is more
expensive because it would be required to temporarily buffering the
equivalent object the compatibility hash needs to be computed over.
A temporary object is needed, because before a hash over an object can
computed it's object header needs to be computed. One of the members of
the object header is the entire size of the object. To know the size of
an equivalent object an entire pass over the original object needs to be
made, as trees, commits, and tags are composed of a variable number of
variable sized pieces. Unfortunately there is no formula to compute the
size of an equivalent object from just the size of the original object.
Avoid all of those future complications by limiting index_bulk_checkin
to only work on blobs.
Inspired-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add mailmap support to ref-filter formats which are similar in
pretty. This support is such that the following pretty placeholders are
equivalent to the new ref-filter atoms:
Additionally, mailmap can also be used with ":trim" option for email by
doing something like "authoremail:mailmap,trim".
The above also applies for the "tagger" atom, that is,
"taggername:mailmap", "taggeremail:mailmap", "taggeremail:mailmap,trim"
and "taggername:mailmap,localpart".
The functionality of ":trim" and ":localpart" remains the same. That is,
":trim" gives the email, but without the angle brackets and ":localpart"
gives the part of the email before the '@' character (if such a
character is not found then we directly grab everything between the
angle brackets).
Mentored-by: Christian Couder <christian.couder@gmail.com> Mentored-by: Hariom Verma <hariom18599@gmail.com> Signed-off-by: Kousik Sanagavarapu <five231003@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Introduce a new function "test_bad_atom", which is similar to
"test_atom()" but should be used to check whether the correct error
message is shown on stderr.
Like "test_atom", the new function takes three arguments. The three
arguments specify the ref, the format and the expected error message
respectively, with an optional fourth argument for tweaking
"test_expect_*" (which is by default "success").
Mentored-by: Christian Couder <christian.couder@gmail.com> Mentored-by: Hariom Verma <hariom18599@gmail.com> Signed-off-by: Kousik Sanagavarapu <five231003@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Previously, when the executable part of "test_expect_{success,failure}"
(inside "test_atom") got "eval"ed, it would have been syntactically
incorrect if the second argument ($2, which is the format) to "test_atom"
were enclosed in single quotes because the $variables would get
interpolated even before the arguments to "test_expect_{success,failure}"
are formed.
So fix this and also some style issues along the way.
Helped-by: Junio C Hamano <gitster@pobox.com> Mentored-by: Christian Couder <christian.couder@gmail.com> Mentored-by: Hariom Verma <hariom18599@gmail.com> Signed-off-by: Kousik Sanagavarapu <five231003@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
By adding the repository variable `ENABLE_COVERITY_SCAN_ON_OS` with a
value, say, `["windows-latest"]`, this GitHub workflow now runs on
Windows, allowing to analyze Windows-specific issues.
This allows, say, the Git for Windows fork to submit Windows builds to
Coverity Scan instead of Linux builds.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
By default, the builds are submitted to the `git` project at
https://scan.coverity.com/projects/git.
The Git for Windows project would like to use this workflow, too,
though, and needs the builds to be submitted to the `git-for-windows`
Coverity project.
To that end, allow configuring the Coverity project name via the
repository variable, you guessed it, `COVERITY_PROJECT`. The default if
that variable is not configured or has an empty value is still `git`.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
It would add a 1GB+ download for every run, better cache it.
This is inspired by the GitHub Action `vapier/coverity-scan-action`,
however, it uses the finer-grained `restore`/`save` method to be able to
cache the Coverity Build Tool even if an unrelated step in the GitHub
workflow fails later on.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
ci: add a GitHub workflow to submit Coverity scans
Coverity is a static analysis tool that detects and generates reports on
various security and code quality issues.
It is particularly useful when diagnosing memory safety issues which may
be used as part of exploiting a security vulnerability.
Coverity's website provides a service that accepts "builds" (which
contains the object files generated during a standard build as well as a
database generated by Coverity's scan tool).
Let's add a GitHub workflow to automate all of this. To avoid running it
without appropriate Coverity configuration (e.g. the token required to
use Coverity's services), the job only runs when the repository variable
"ENABLE_COVERITY_SCAN_FOR_BRANCHES" has been configured accordingly (see
https://docs.github.com/en/actions/learn-github-actions/variables for
details how to configure repository variables): It is expected to be a
valid JSON array of branch strings, e.g. `["main", "next"]`.
In addition, this workflow requires two repository secrets:
- COVERITY_SCAN_EMAIL: the email to send the report to, and
- COVERITY_SCAN_TOKEN: the Coverity token (look in the Project Settings
tab of your Coverity project).
Note: The initial version of this patch used
`vapier/coverity-scan-action` to benefit from that Action's caching of
the Coverity tool, which is rather large. Sadly, that Action only
supports Linux, and we want to have the option of building on Windows,
too. Besides, in the meantime Coverity requires `cov-configure` to be
runantime, and that Action was not adjusted accordingly, i.e. it seems
not to be maintained actively. Therefore it would seem prudent to
implement the steps manually instead of using that Action.
Initial-patch-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
revision: make pseudo-opt flags read via stdin behave consistently
When reading revisions from stdin via git-rev-list(1)'s `--stdin` option
then these revisions never honor flags like `--not` which have been
passed on the command line. Thus, an invocation like e.g. `git rev-list
--all --not --stdin` will not treat all revisions read from stdin as
uninteresting. While this behaviour may be surprising to a user, it's
been this way ever since it has been introduced via 42cabc341c4 (Teach
rev-list an option to read revs from the standard input., 2006-09-05).
With that said, in c40f0b7877 (revision: handle pseudo-opts in `--stdin`
mode, 2023-06-15) we have introduced a new mode to read pseudo opts from
standard input where this behaviour is a lot more confusing. If you pass
`--not` via stdin, it will:
- Influence subsequent revisions or pseudo-options passed on the
command line.
- Influence pseudo-options passed via standard input.
- _Not_ influence normal revisions passed via standard input.
This behaviour is extremely inconsistent and bound to cause confusion.
While it would be nice to retroactively change the behaviour for how
`--not` and `--stdin` behave together, chances are quite high that this
would break existing scripts that expect the current behaviour that has
been around for many years by now. This is thus not really a viable
option to explore to fix the inconsistency.
Instead, we change the behaviour of how pseudo-opts read via standard
input influence the flags such that the effect is fully localized. With
this change, when reading `--not` via standard input, it will:
- _Not_ influence subsequent revisions or pseudo-options passed on
the command line, which is a change in behaviour.
- Influence pseudo-options passed via standard input.
- Influence normal revisions passed via standard input, which is a
change in behaviour.
Thus, all flags read via standard input are fully self-contained to that
standard input, only.
While this is a breaking change as well, the behaviour has only been
recently introduced with Git v2.42.0. Furthermore, the current behaviour
can be regarded as a simple bug. With that in mind it feels like the
right thing to retroactively change it and make the behaviour sane.
Signed-off-by: Patrick Steinhardt <ps@pks.im> Reported-by: Christian Couder <christian.couder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano [Sat, 23 Sep 2023 00:01:36 +0000 (17:01 -0700)]
Merge branch 'jk/ort-unused-parameter-cleanups'
Code clean-up.
* jk/ort-unused-parameter-cleanups:
merge-ort: lowercase a few error messages
merge-ort: drop unused "opt" parameter from merge_check_renames_reusable()
merge-ort: drop unused parameters from detect_and_process_renames()
merge-ort: stop passing "opt" to read_oid_strbuf()
merge-ort: drop custom err() function
Junio C Hamano [Sat, 23 Sep 2023 00:01:36 +0000 (17:01 -0700)]
Merge branch 'la/trailer-cleanups'
Code clean-up.
Keep only the first three clean-ups, and discard the rest to be replaced later.
cf. <owly1qetjqo1.fsf@fine.c.googlers.com>
cf. <owlyzg1dsswr.fsf@fine.c.googlers.com>
* la/trailer-cleanups:
trailer: split process_command_line_args into separate functions
trailer: split process_input_file into separate pieces
trailer: separate public from internal portion of trailer_iterator
Jeff King [Thu, 21 Sep 2023 04:18:25 +0000 (00:18 -0400)]
test-lib: set UBSAN_OPTIONS to match ASan
For a long time we have used ASAN_OPTIONS to set abort_on_error. This is
important because we want to notice detected problems even in programs
which are expected to fail. But we never did the same for UBSAN_OPTIONS.
This means that our UBSan test suite runs might silently miss some
cases.
It also causes a more visible effect, which is that t4058 complains
about unexpected "fixes" (and this is how I noticed the issue):
$ make SANITIZE=undefined CC=gcc && (cd t && ./t4058-*)
...
ok 8 - git read-tree does not segfault # TODO known breakage vanished
ok 9 - reset --hard does not segfault # TODO known breakage vanished
ok 10 - git diff HEAD does not segfault # TODO known breakage vanished
The tests themselves aren't that interesting. We have a known bug where
these programs segfault, and they do when compiled without sanitizers.
With UBSan, when the test runs:
test_might_fail git read-tree --reset base
it gets:
cache-tree.c:935:9: runtime error: member access within misaligned address 0x5a5a5a5a5a5a5a5a for type 'struct cache_entry', which requires 8 byte alignment
So that's garbage memory which would _usually_ cause us to segfault, but
UBSan catches it and complains first about the alignment. That makes
sense, but the weird thing is that UBSan then exits instead of aborting,
so our test_might_fail call considers that an acceptable outcome and the
test "passes".
Curiously, this historically seems to have aborted, because I've run
"make test" with UBSan many times (and so did our CI) and we never saw
the problem. Even more curiously, I see an abort if I use clang with
ASan and UBSan together, like:
# this aborts!
make SANITIZE=undefined,address CC=clang
But not with just UBSan, and not with both when used with gcc:
# none of these do
make SANITIZE=undefined CC=gcc
make SANITIZE=undefined CC=clang
make SANITIZE=undefined,address CC=gcc
Likewise moving to older versions of gcc (I tried gcc-11 and gcc-12 on
my Debian system) doesn't abort. Nor does moving around in Git's
history. Neither this test nor the relevant code have been touched in a
while, and going back to v2.41.0 produces the same outcome (even though
many UBSan CI runs have passed in the meantime).
So _something_ changed on my system (and likely will soon on other
people's, since this is stock Debian unstable), but I didn't track
it further. I don't know why it ever aborted in the past, but we
definitely should be explicit here and tell UBSan what we want to
happen.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano [Wed, 20 Sep 2023 18:28:22 +0000 (11:28 -0700)]
completion: loosen and document the requirement around completing alias
Recently we started to tell users to spell ": git foo ;" with
space(s) around 'foo' for an alias to be completed similarly
to the 'git foo' command. It however is easy to also allow users to
spell it in a more natural way with the semicolon attached to 'foo',
i.e. ": git foo;". Also, add a comment to note that 'git' is optional
and writing ": foo;" would complete the alias just fine.
Junio C Hamano [Wed, 20 Sep 2023 17:45:12 +0000 (10:45 -0700)]
Merge branch 'jc/update-index-show-index-version'
"git update-index" learns "--show-index-version" to inspect
the index format version used by the on-disk index file.
* jc/update-index-show-index-version:
test-tool: retire "index-version"
update-index: add --show-index-version
update-index doc: v4 is OK with JGit and libgit2
Junio C Hamano [Wed, 20 Sep 2023 17:44:57 +0000 (10:44 -0700)]
Merge branch 'js/diff-cached-fsmonitor-fix'
"git diff --cached" codepath did not fill the necessary stat
information for a file when fsmonitor knows it is clean and ended
up behaving as if it is not clean, which has been corrected.
* js/diff-cached-fsmonitor-fix:
diff-lib: fix check_removed when fsmonitor is on