user/sven/git.git/cache-tree.c, branch v2.49.0-rc2

global: mark code units that generate warnings with `-Wsign-compare`

2024-12-06T11:20:02Z

Mark code units that generate warnings with `-Wsign-compare`. This allows for a structured approach to get rid of all such warnings over time in a way that can be easily measured. Signed-off-by: Patrick Steinhardt Signed-off-by: Junio C Hamano

Merge branch 'ps/cache-tree-w-broken-index-entry'

2024-10-22T18:40:38Z

Fail gracefully instead of crashing when attempting to write the contents of a corrupt in-core index as a tree object. * ps/cache-tree-w-broken-index-entry: unpack-trees: detect mismatching number of cache-tree/index entries cache-tree: detect mismatching number of index entries cache-tree: refactor verification to return error codes

cache-tree: detect mismatching number of index entries

2024-10-07T22:08:11Z

In t4058 we have some tests that exercise git-read-tree(1) when used with a tree that contains duplicate entries. While the expectation is that we fail, we ideally should fail gracefully without a segfault. But that is not the case: we never check that the number of entries in the cache-tree is less than or equal to the number of entries in the index. This can lead to an out-of-bounds read as we unconditionally access `istate->cache[idx]`, where `idx` is controlled by the number of cache-tree entries and the current position therein. The result is a segfault. Fix this segfault by adding a sanity check for the number of index entries before dereferencing them. Signed-off-by: Patrick Steinhardt Signed-off-by: Junio C Hamano

cache-tree: refactor verification to return error codes

2024-10-07T22:08:11Z

The function `cache_tree_verify()` will `BUG()` whenever it finds that the cache-tree extension of the index is corrupt. The function is thus inherently untestable because the resulting call to `abort()` will be detected by our testing framework and labelled an error. And rightfully so: it shouldn't ever be possible to hit bugs, as they should indicate a programming error rather than corruption of on-disk state. Refactor the function to instead return error codes. This also ensures that the function can be used e.g. by git-fsck(1) without the whole process dying. Furthermore, this refactoring plugs some memory leaks when returning early by creating a common exit path. Signed-off-by: Patrick Steinhardt Signed-off-by: Junio C Hamano

environment: make `get_git_dir()` accept a repository

2024-09-12T17:15:39Z

The `get_git_dir()` function retrieves the path to the Git directory for `the_repository`. Make it accept a `struct repository` such that it can work on arbitrary repositories and make it part of the repository subsystem. This reduces our reliance on `the_repository` and clarifies scope. Signed-off-by: Patrick Steinhardt Signed-off-by: Junio C Hamano

global: introduce `USE_THE_REPOSITORY_VARIABLE` macro

2024-06-14T17:26:33Z

Use of the `the_repository` variable is deprecated nowadays, and we slowly but steadily convert the codebase to not use it anymore. Instead, callers should be passing down the repository to work on via parameters. It is hard though to prove that a given code unit does not use this variable anymore. The most trivial case, merely demonstrating that there is no direct use of `the_repository`, is already a bit of a pain during code reviews as the reviewer needs to manually verify claims made by the patch author. The bigger problem though is that we have many interfaces that implicitly rely on `the_repository`. Introduce a new `USE_THE_REPOSITORY_VARIABLE` macro that allows code units to opt into usage of `the_repository`. The intent of this macro is to demonstrate that a certain code unit does not use this variable anymore, and to keep it from new dependencies on it in future changes, be it explicit or implicit For now, the macro only guards `the_repository` itself as well as `the_hash_algo`. There are many more known interfaces where we have an implicit dependency on `the_repository`, but those are not guarded at the current point in time. Over time though, we should start to add guards as required (or even better, just remove them). Define the macro as required in our code units. As expected, most of our code still relies on the global variable. Nearly all of our builtins rely on the variable as there is no way yet to pass `the_repository` to their entry point. For now, declare the macro in "biultin.h" to keep the required changes at least a little bit more contained. Signed-off-by: Patrick Steinhardt Signed-off-by: Junio C Hamano

hash: require hash algorithm in `is_empty_{blob,tree}_oid()`

2024-06-14T17:26:33Z

Both functions `is_empty_{blob,tree}_oid()` use `the_repository` to derive the hash function that shall be used. Require callers to pass in the hash algorithm to get rid of this implicit dependency. Signed-off-by: Patrick Steinhardt Signed-off-by: Junio C Hamano

hash: require hash algorithm in `oidread()` and `oidclr()`

2024-06-14T17:26:32Z

Both `oidread()` and `oidclr()` use `the_repository` to derive the hash function that shall be used. Require callers to pass in the hash algorithm to get rid of this implicit dependency. Signed-off-by: Patrick Steinhardt Signed-off-by: Junio C Hamano

Merge branch 'eb/hash-transition'

2024-03-28T21:13:50Z

Work to support a repository that work with both SHA-1 and SHA-256 hash algorithms has started. * eb/hash-transition: (30 commits) t1016-compatObjectFormat: add tests to verify the conversion between objects t1006: test oid compatibility with cat-file t1006: rename sha1 to oid test-lib: compute the compatibility hash so tests may use it builtin/ls-tree: let the oid determine the output algorithm object-file: handle compat objects in check_object_signature tree-walk: init_tree_desc take an oid to get the hash algorithm builtin/cat-file: let the oid determine the output algorithm rev-parse: add an --output-object-format parameter repository: implement extensions.compatObjectFormat object-file: update object_info_extended to reencode objects object-file-convert: convert commits that embed signed tags object-file-convert: convert commit objects when writing object-file-convert: don't leak when converting tag objects object-file-convert: convert tag objects when writing object-file-convert: add a function to convert trees between algorithms object: factor out parse_mode out of fast-import and tree-walk into in object.h cache: add a function to read an OID of a specific algorithm tag: sign both hashes commit: export add_header_signature to support handling signatures on tags ...

Merge branch 'js/merge-tree-3-trees'

2024-03-07T23:59:41Z

"git merge-tree" has learned that the three trees involved in the 3-way merge only need to be trees, not necessarily commits. * js/merge-tree-3-trees: fill_tree_descriptor(): mark error message for translation cache-tree: avoid an unnecessary check Always check `parse_tree*()`'s return value t4301: verify that merge-tree fails on missing blob objects merge-ort: do check `parse_tree()`'s return value merge-tree: fail with a non-zero exit code on missing tree objects merge-tree: accept 3 trees as arguments