README.md

gpr-rust

Gpr-Rust is a Rust binding for gpr. its goal is to provide an easy way to integrate Ada sources into the Rust build process. It allows to select and build a GNAT project file by parsing the project and providing all required information to call gprbuild and link the resulting library.

Dependencies

To build this project a working installation of alire is required. You can download Alire here. The build script will automatically download the required dependencies. The toolchain and dependencies used to build this crate are only available for the crates build process. For any Ada projects that are being built with this crate an appropriate toolchain needs to be provided.

Addionally the following native C libraries are required:

• libgmp-dev
• libssl-dev

Usage

This library is intended to be used in build scripts. The basic process consists of three steps.

• Loading the project:

let project = gpr::Project::load(Path::new("/path/to/project.gpr")).unwrap();

• Building the project:

let output = Command::new("gprbuild")
    .args(project.gprbuild_args().unwrap())
    .stderr(Stdio::inherit())
    .output()
    .unwrap();

if !output.status.success() {
    panic!();
}

• Providing cargo with the required linker flags:

println!(
    "cargo:rustc-link-search{}",
    project.library_dir().unwrap().to_str().unwrap()
);
println!(
    "cargo:rustc-link-lib={}={}",
    project.library_kind().unwrap(),
    project.library_name().unwrap()
);

• Additionally it can be helpful to tell cargo that changes in the Ada code also should trigger a rerun:

for dir in project.source_dirs().unwrap() {
    println!(
        "cargo:rerun-if-changed={}", dir.as_str()
    );
}

Gpr-Rust doesn't need much configuration, most of the code needed is boilerplate. If any additional options are required to build the Ada project these can be added as arguments to the gprbuild command.

An example project is located in examples/ada_hello/build.rs. It can be tested by running:

cd examples/ada_hello
LD_LIBRARY_PATH=ada_hello/lib cargo run