banan-os

This is my hobby operating system written in C++. Currently supports x86_64 and i686 architectures.

You can find a live demo here

Features

General

• Ring3 userspace
• SMP (multiprocessing)
• Linear framebuffer (VESA and GOP)
• Network stack
• ELF executable loading
• AML interpreter (partial)
• ELF dynamic linking
• Graphical desktop
• copy-on-write memory

Drivers

• NVMe disks
• ATA (IDE, SATA) disks
• E1000 and E1000E NICs
• PS2 keyboard (all scancode sets)
• PS2 mouse
• USB
• virtio devices (network, storage)

Network

• ARP
• ICMP
• IPv4
• UDP
• TCP (partial and buggy)
• Unix domain sockets

Filesystems

• Virtual filesystem
• Ext2
• FAT12/16/32
• Dev
• Ram
• Proc
• Sys
• 9P

Bootloader support

• GRUB
• Custom BIOS bootloader
• Custom UEFI bootloader

Code structure

Each major component and library has its own subdirectory (kernel, userspace, libc, ...). Each directory contains directory include, which has all of the header files of the component. Every header is included by its absolute path.

Building

Needed packages

apt (tested on ubuntu 22.04)

# apt install build-essential git ninja-build texinfo bison flex libgmp-dev libmpfr-dev libmpc-dev parted qemu-system-x86 cpu-checker

pacman

# pacman -S --needed base-devel git wget cmake ninja parted qemu-system-x86

Compilation

To build the toolchain for this os. You can run the following command.

NOTE: The following step has to be done only once. This might take a long time since we are compiling binutils and gcc.

./bos toolchain

To build the os itself you can run one of the following commands. You will need root access for disk image creation/modification.

./bos qemu
./bos qemu-nographic
./bos qemu-debug
./bos bochs

You can also build the kernel or disk image without running it:

./bos kernel
./bos image

To build for other architectures set environment variable BANAN_ARCH=arch (e.g. BANAN_ARCH=i686).

To change the bootloader you can set environment variable BANAN_BOOTLOADER; supported values are BANAN (my custom bootloader) and GRUB.

To run with UEFI set environment variable BANAN_UEFI_BOOT=1. You will also have to set OVMF_PATH to the correct OVMF (default /usr/share/ovmf/x64/OVMF.fd).

If you have corrupted your disk image or want to create new one, you can either manually delete build/banan-os.img and build system will automatically create you a new one or you can run the following command.

./bos image-full

I have also created shell completion script for zsh. You can either copy the file in script/shell-completion/zsh/_bos to /usr/share/zsh/site-functions/ or add the script/shell-completion/zsh to your fpath in .zshrc.

Contributing

As the upstream is hosted on my server https://git.bananymous.com/Bananymous/banan-os, please contact me about account creation (email, discord) and I will add a account for you. This is done to limit the people with access to the server.

As this is mostly a learning experience for me, I would appreciate if you first contacted me about adding new features (email, discord, issue, ...). Bug fixes are always welcome!

Commit message should be formatted followingly

1. First line is of the form "Subject: Description", where Subject tells the area touched (Kernel, Shell, BuildSystem, ...) and Description is brief description of the change done. First line should fit fully in 70 characters.
2. Body of the message should further describe the change and reasoning behind the change.

All commits should pass the pre-commit hook defined in .pre-commit-config.yaml. For instructions on how to setup pre-commit, please see https://pre-commit.com/#install.