Mantle

What is Mantle?

Mantle is a hobbyist Operating System Kernel I am working on to learn more about different CPU architectures (currently x86/amd64), Operating System concepts, and to get more C/Assembly programming practice. I also hope that this project will serve as a good learning reference for others interested in OS development.

Repository Hierarchy

• arch - Architecture specific code.
  • arch/include - Architecture specific header files.
• docs - Documentation.
• include - Architecture independent headers.
• lib - Platform independent library functions.

Toolchain

• Linux x86_64 GCC Cross Compiler - Download here.
• Makefile - [GNU] Makefile used to build the kernel.
  • [g]make - Builds the kernel image file.
  • [g]make iso - Builds an iso image with GRUB as the bootloader.
  • [g]make clean - Deletes all object files and the kernel image/iso file(s).
• link.ld - Linker script that organizes the binary layout.
• grub.cfg - Basic GRUB config file.
• configure.py - Python 3 script that updates the following files:
  • Running ./configure.py -c clean will run git checkout on each file.
• mantle.conf - Project configuration file, contains various options.
  • Name: The project name.
  • Version: The version string.
  • Codename: The codename.

Dependencies

• GCC Cross Compiler
• Python 3
• NASM
• grub2
• xorriso (>= 1.2.9)

Building / Testing

1. ./configure.py -a amd64
2. make iso
3. Either burn to USB or qemu-system-x86_64 -cdrom <ISO> -m 2G

Branches

• master - Mainline branch. Documentation, and feature/subsystem merges are committed to this branch.
• <branch> - Branches meant for development of specific features/subsystems (i.e. paging).

Coding Convention

• All uppercase for Macros and Constants with underscores for spaces (i.e. FG_WHITE).
• Camelcase for Structs and Struct Typedefs (i.e. IdtDescriptor).
• All lowercase, underscores for spaces, and subsystem prefix for function names (i.e. cpuid_vendor).

Editing

For syntax highlighting of the types in kernel/types.h, create a file called ~/.vim/after/syntax/c.vim and add the following lines:

• syn keyword cType uchar_t ushort_t uint_t ulong_t
• syn keyword cType byte_t word_t dword_t qword_t