# RustyHermit: libhermit-rs [](https://hermitcore.github.io/libhermit-rs/hermit/) [](https://img.shields.io/crates/l/rusty-hermit.svg) [](https://matrix.osbyexample.com:3008) _libhermit-rs_ is the kernel of the [RustyHermit](https://github.com/hermitcore/rusty-hermit) unikernel project. ## Building the kernel Usually the kernel will be linked as static library to your applications. - **Rust applications:** Instructions can be found in the [rusty-hermit](https://github.com/hermitcore/rusty-hermit) repository. - **For C/C++ applications:** Instructions can be found in the [hermit-playground](https://github.com/hermitcore/hermit-playground) repository. ### Standalone static library build If this does not fit your needs and you want to build the kernel as static library to link afterwards, you need the following: The Rust **nightly** toolchain ([official webpage](https://www.rust-lang.org/)), the source code of the Rust runtime, and llvm-tools: ```sh rustup toolchain install nightly rustup component add rust-src llvm-tools-preview ``` You can then build `libhermit-rs` with the following command ```sh cargo build -Z build-std=core,alloc,panic_abort --target x86_64-unknown-none-hermitkernel ``` The resulting library then can be found in `target/x86_64-unknown-none-hermitkernel/debug/libhermit.a` ### Control the kernel messages verbosity _libhermit-rs_ uses the lightweight logging crate [log](https://github.com/rust-lang/log) to print kernel messages. The environment variable `HERMIT_LOG_LEVEL_FILTER` controls the verbosity. You can change it by setting it at compile time to a string matching the name of a [LevelFilter](https://docs.rs/log/0.4.8/log/enum.LevelFilter.html). If the variable is not set, or the name doesn't match, then `LevelFilter::Info` is used by default. ```sh $ HERMIT_LOG_LEVEL_FILTER=Debug cargo build -Z build-std=core,alloc,panic_abort --target x86_64-unknown-none-hermitkernel ``` ## Credits _libhermit-rs_ is derived from following tutorials and software distributions: 1. Philipp Oppermann's [excellent series of blog posts][opp]. 2. Erik Kidd's [toyos-rs][kidd], which is an extension of Philipp Opermann's kernel. 3. The Rust-based teaching operating system [eduOS-rs][eduos]. [opp]: http://blog.phil-opp.com/ [kidd]: http://www.randomhacks.net/bare-metal-rust/ [eduos]: http://rwth-os.github.io/eduOS-rs/ HermitCore's Emoji is provided for free by [EmojiOne](https://www.gfxmag.com/crab-emoji-vector-icon/). ## License Licensed under either of * Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0) * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT) at your option. ## Contribution Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions. libhermit-rs is being developed on [GitHub](https://github.com/hermitcore/libhermit-rs). Create your own fork, send us a pull request, and chat with us on [Slack](https://matrix.osbyexample.com:3008)