conan2-rs

Introduction

conan2-rs is a Cargo build script wrapper of the Conan C/C++ package manager (version 2.0 only).

It automatically pulls the C/C++ library linking flags from Conan dependencies and passes them to rustc.

Adding C/C++ dependencies using Conan

The simplest way to add C/C++ dependencies to a Rust project using Conan is to add a plain conanfile.txt file as follows:

[requires]
libxml2/2.11.4
openssl/3.1.3
zlib/1.3

Example usage

Add conan2 to the Cargo.toml build dependencies section:

[build-dependencies]
conan2 = "0.1"

Add the following lines to the project build.rs script to invoke conan install and pass the Conan dependency information to Cargo automatically:

use conan2::ConanInstall;

fn main() {
    ConanInstall::new().run().parse().emit();
}

The most commonly used build_type Conan setting will be defined automatically depending on the current Cargo build profile: Debug or Release.

The Conan executable is assumed to be named conan unless the CONAN environment variable is set to override.

An example Rust crate using conan2-rs to link Conan dependencies can also be found in the project repository.

Advanced usage

Using custom Conan profiles with names derived from the Cargo target information and a reduced output verbosity level:

use conan2::{ConanInstall, ConanVerbosity};

fn main() {
    let target_os = std::env::var("CARGO_CFG_TARGET_OS").unwrap();
    let target_arch = std::env::var("CARGO_CFG_TARGET_ARCH").unwrap();
    let conan_profile = format!("{}-{}", target_os, target_arch);

    ConanInstall::new()
        .profile(&conan_profile)
        .detect_profile() // Auto-detect if the profile does not exist
        .build("missing")
        .verbosity(ConanVerbosity::Error) // Silence Conan warnings
        .run()
        .parse()
        .emit();
}

Getting C/C++ include paths from Conan dependencies

To use the list of include paths, do the following after parsing the conan install output:

use conan2::ConanInstall;

let metadata = ConanInstall::new().run().parse();

for path in metadata.include_paths() {
    // Add "-I{path}" to CXXFLAGS or something.
}

metadata.emit();