git/contrib/libgit-sys/src, branch main

libgit: add higher-level libgit crate

2025-01-29T23:06:50Z

The C functions exported by libgit-sys do not provide an idiomatic Rust interface. To make it easier to use these functions via Rust, add a higher-level "libgit" crate, that wraps the lower-level configset API with an interface that is more Rust-y. This combination of $X and $X-sys crates is a common pattern for FFI in Rust, as documented in "The Cargo Book" [1]. [1] https://doc.rust-lang.org/cargo/reference/build-scripts.html#-sys-packages Co-authored-by: Josh Steadmon Signed-off-by: Josh Steadmon Signed-off-by: Calvin Wan Signed-off-by: Junio C Hamano

libgit-sys: also export some config_set functions

2025-01-29T23:06:50Z

In preparation for implementing a higher-level Rust API for accessing Git configs, export some of the upstream configset API via libgitpub and libgit-sys. Since this will be exercised as part of the higher-level API in the next commit, no tests have been added for libgit-sys. While we're at it, add git_configset_alloc() and git_configset_free() functions in libgitpub so that callers can manage config_set structs on the heap. This also allows non-C external consumers to treat config_sets as opaque structs. Co-authored-by: Calvin Wan Signed-off-by: Calvin Wan Signed-off-by: Josh Steadmon Signed-off-by: Junio C Hamano

libgit-sys: introduce Rust wrapper for libgit.a

2025-01-28T22:45:47Z

Introduce libgit-sys, a Rust wrapper crate that allows Rust code to call functions in libgit.a. This initial patch defines build rules and an interface that exposes user agent string getter functions as a proof of concept. This library can be tested with `cargo test`. In later commits, a higher-level library containing a more Rust-friendly interface will be added at `contrib/libgit-rs`. Symbols in libgit can collide with symbols from other libraries such as libgit2. We avoid this by first exposing library symbols in public_symbol_export.[ch]. These symbols are prepended with "libgit_" to avoid collisions and set to visible using a visibility pragma. In build.rs, Rust builds contrib/libgit-rs/libgit-sys/libgitpub.a, which also contains libgit.a and other dependent libraries, with -fvisibility=hidden to hide all symbols within those libraries that haven't been exposed with a visibility pragma. Co-authored-by: Kyle Lippincott Co-authored-by: Calvin Wan Signed-off-by: Calvin Wan Signed-off-by: Kyle Lippincott Signed-off-by: Josh Steadmon Signed-off-by: Junio C Hamano