# Luna
A simple POSIX-based operating system for 64-bit computers, written in C++.

## Another UNIX clone?
[Yes, another UNIX clone](https://wiki.osdev.org/User:Sortie/Yes_Another_Unix_Clone).

## Features
- Lightweight 64-bit [kernel](kernel/). Compatible with the x86_64 architecture.
- Basic threads/processes, using a simple round-robin [scheduler](kernel/src/thread/).
- Read-only [ext2](kernel/src/fs/ext2/) filesystem.
- Can [load ELF executables](kernel/src/binfmt/ELF.cpp), [shebang scripts](kernel/src/binfmt/Script.cpp) or [arbitrary binary formats](kernel/src/binfmt/BinaryFormat.h) (registered through kernel modules, which are not supported yet =D).
- [C Library](libc/), aiming for POSIX compatibility, with many features such as local domain sockets, signals, and shared memory.
- Support for [several third-party programs](ports/), including the [GNU binutils](ports/binutils/PACKAGE) suite of utilities and the [GCC](ports/gcc/PACKAGE) compiler.
- Designed to be [portable](kernel/src/arch), so that additional architectures can be added in the future with relatively low effort.
- Everything text-related is designed around [UTF-8](libluna/include/luna/Utf8.h).
- Environment-agnostic [utility library](libluna/), which can be used in both kernel and userspace.
- An extensive set of [standard Unix utilities](apps/), from [ls](apps/ls.cpp) to [uname](apps/uname.cpp) to [base64](apps/base64.cpp). Written in modern C++ and very small amounts of code, using Luna's practical [OS library](libos/).
- A simple and efficient [windowing system](wind/), providing a lightweight GUI environment (still in development, not many GUI apps exist).

## Screenshot
![Screenshot as of 0.6.0](docs/screenshots/screenshot-0.6.0.png)

## Setup

To build and run Luna, you will need to build a [cross-compiler](https://wiki.osdev.org/Why_do_I_need_a_Cross_Compiler) and cross-binutils for `x86_64-luna`.

For this, you should start by installing the [required dependencies](https://wiki.osdev.org/GCC_Cross_Compiler#Installing_Dependencies).

Then, run `tools/setup.sh` to build the toolchain.

Please beware that building GCC and Binutils can take some time, depending on your machine.

## Running

To run Luna in a virtual machine, you should have [QEMU](https://www.qemu.org/) installed.

Additionally, the build process needs some extra dependencies to run: `cmake`, `ninja`, `nasm`, `fakeroot` and `genext2fs`.

`tools/run.sh` is the script you should use in most cases. It will build changed files, install, make an ISO image, and run Luna in QEMU.

If you have no toolchain set up, `run.sh` will build it automatically, which means that you don't necessarily have to run `setup.sh` manually since `run.sh` does it for you.

## Prebuilt images

Prebuilt ISO images for every release version can be found at [pub.cloudapio.eu](https://pub.cloudapio.eu/luna/releases).

## Is there third-party software I can use on Luna?

Yes! A ports system is in place, and you can use the build scripts to add some ports to your image. More information in the [Ports](ports/README.md) page.

## License
Luna is open-source and free software under the [BSD-2-Clause License](LICENSE).