# <img width="40" height="40" alt="red-pepper" src="https://i.ibb.co/mrHH6d1m/pixil-frame-0-4.png" /> pepperOS: "will never be done"

## Trying the kernel

First install the dependencies: `sudo apt install python3 xorriso make qemu-system`

Also, you have to get an x86_64 toolchain for compilation. The easiest way to do that on most systems is to install it from Homebrew:

```
brew install x86_64-elf-gcc
```

Then, to compile the kernel and make an ISO image file: `make build-iso`
To run it with QEMU, `make run`

## TODO

The basics that I'm targeting are:

### Basic utility of what we call a "kernel"

- Implement tasks, and task switching + context switching and spinlock acquire/release
- Load an executable
- Filesystem (TAR for read-only initfs, then maybe read-write using FAT12/16/32 or easier fs) w/ VFS layer
- Getting to userspace (ring 3 switching, syscall interface)
- Porting musl libc or equivalent

### Scalability/maintenance/expansion features

- Documentation
- SOME error handling in functions
- Unit tests
- Good error codes (like Linux kernel: ENOMEM, ENOENT, ...)

### Optional features

In the future, maybe?
- SMP support (Limine provides functionality to make this easier)
- Parsing the ACPI tables and using them for something
- Replacing the PIT timer with APIC

## Thanks

PepperOS wouldn't be possible without the following freely-licensed software:

- the [Limine](https://codeberg.org/Limine/Limine) portable bootloader
- Marco Paland's freestanding [printf implementation](https://github.com/mpaland)
- Mintuski's [Flanterm](https://codeberg.org/Mintsuki/Flanterm) terminal emulator

...and without these amazing resources:

- the [OSDev](https://osdev.org) wiki & forums
- Intel 64 and IA-32 Architectures Software Developer's Manual
- Documentation for the [GNU Compiler Collection](https://gcc.gnu.org/onlinedocs/gcc/)