OmochaOS

OmochaOS is my personal studying project. Some code and lower design is inherited from my old project archive branch OmochaOS(original archive). Why am I interseted in OS-Developing is under the readme of that branch.

This branch of OmochaOS is directly forked from VenlafaxOS which was already archived. I will face my future and break the dependence of medicine. So I deciced not to use VenlafaxOS as a name anymore.

Build

Run make in project root dir.

• dependencies

  • python3 (with pyyaml supported)
  • compiling-toolchain (gcc ar ld nm objdump objcopy)
    • set TOOLCHAIN_PREFIX in Makefile to use croee-compiler, this project is developed under MacOS and built passed on Linux-based system. If you are using MacOS, install x86_64-elf-binutils and x86_64-elf-gcc is good enough. If you are using Linux, just make sure above tools is installed. Otherwise you may figure it out on your platform.
  • nasm
  • useful utilities (cat sed awk tee)

• build process

  • compile kernel's core and modules within kernel space into object
  • link some general used code and syscall wrapping into libos.a
  • compile init code (linked with libos.a) into elf executable file init.out
  • compile init package.S to object init.out.o which contains full content of init.out by using .incbin
  • link kernel object and init.out.o to kernel.out
  • build modules (not modules in kernel dir that's builtin modules)

Build boot image

Run make boot in project root dir. This command is depend on make attach and make detach which only implement on MacOS (based on hdiutil and diskutil comes with macos) and Linux (based on udisksctl controlled loop-device). If you cannot make it, try to implement it yourself or build image yourself. This command uses rsync to copy everything in tools/root_dir to image's root dir and cp to copy grub.cfg to /boot/grub/grub.cfg of image. This command copies tools/HD_grub2.img (which contains a formatted disk image with grub2 installed and a FAT32 part. FAT32 part is the first part of disk, contains grub2 boot files.)

Run

Run make qemu or make bochs in project root dir.

• dependencies

  • bochs or qemu

Debug

If qemu/bochs is installed and make attach/detach is implemented. You can use make debug DEBUG_WAY=qemu/bochs to build and run in one command.

System Design

Omochaos is micro-kernel but with memory and systask running in kernel space (has kernel symbol linked) Currently most of modules are running in kernel space. Those modules will exit when modules from disk is properly loaded. All of modules are running under ring 1. Only two syscall __recv_msg and __send_msg, interrupt_handler are running under ring 0 after core finish boot up. systask should give a common way to access core data in struct environment(not impl yet)

Road Map

• VFS
• Port Newlib
• Shabby Shell
• ACPI
• SMP Support
• Process scheduler
• Graphic Interface

Thanks