TermOS

An x86 based hobby OS made from scratch

Features

• Custom bootloader written in x86 asm
• Kernel's own libc (library used by the kernel as well as the user programs)
• Linear memory manager (physical memory only)
• SimpleFS File System support (inode based)
• Necessary drivers (Keyboard, Screen, ATA)
• Program interface to register and handle user programs (though they still run in kernel space)
• A simple system shell to execute commands (and run user programs) - No GUI
• FCFS program scheduler (can also interrupt the queue and enqueue new programs with LCtrl+C)
• Multiple commands can also be added to the queue from a file and executed using command "fexec <file descrpitor>"

Possible Features

• File system abstraction in libc
• A decent text editor
• Task Management using Task State Segment (TSS) feature of x86
• Round Robin scheduling of tasks
• A better memory manager

Build Instructions

Requirements

• i386-elf-gcc (crosscompiler toolchain)
• i386-elf-gdb (for debugging)
• nasm (Netwide assembler)
• qemu-system-i386 (included in qemu-arch-extra package in Arch Linux)
• make

To Build

• Change the paths for CC and GDB in the Makefile, if required
• Run the command: qemu-img create hdd.img 512M to create a virtual image for hard disk
• Then run:
  make - to build
  make run - to build and run the OS on qemu
  make debug - to build and start gdb server (change the debug rule in Makefile, if required)
• Note: After running the OS for first time, run the OS command formatfs to format hdd.img with SimpleFS
  
  

Find the full project report here: https://docs.google.com/document/d/e/2PACX-1vQ-U2EtcHYvwEpf5zWgf_OnuEpHnjlT0J8zZ0_djFvCirTCkCu-3jNLo5R0jY5SCs4F849UCYV8o1Dq/pub