See also: Home, Developer Guide

Current todo

  • ❏ Add Rust compilation support for kernel

  • ✓ Refactor kernel dylib system to kernel modules

  • ❏ Add dynamic linker support for kernel

  • ✓ Make kernel not use the reserved memory region and only BSS + Heap

  • ❏ FAT LFN support

  • ❏ ATAPI and ISO9660 optical driver support

  • ✓ Fix usermode programs not able to read from stdin

  • ❏ Create custom bootloader

  • ❏ DMA mode hardware drivers

  • ✓ External runtime dependencies compiled during build not toolchain

  • ❏ Make kernel PIC & PIE

  • ❏ Smart heap allocation for kernel that actually "frees" the memory

Phase 1: Core OS Infrastructure (Current)

Memory Management

  • ✓ Virtual memory / paging (per-process address spaces)

  • ✓ Heap management (brk/sbrk syscalls for malloc)

  • ✓ Stack management (per-process user stacks)

    • ✓ Refactor user stack allocation (move from process.c to stack.c)

    • ✓ Implement Stack_CreateUser using PMM/Paging (not kmalloc)

    • ✓ Map user-mode exit trampoline (fix GPF on return)

    • ✓ Update TSS ESP0 on context switch

  • ❏ Memory protection (read/write/execute permissions)

  • ✓ Page tables and MMU setup

Process Management

  • ✓ Process Control Block (PCB) structure

  • ❏ Process creation & destroy (fork/execve syscalls)

    • ✓ Add Kernel Stack to Process Struct

    • ✓ Allocate Kernel Stack in Process_Create

    • ✓ Free Kernel Stack in Process_Destroy

    • ✓ Set Parent PID

    • ❏ Initialize Standard File Descriptors (stdin, stdout, stderr)

    • ✓ Handle Arguments (argv/envp)

    • ✓ Scheduler Registration

  • ✓ Process scheduling & context switching (basic round-robin)

  • ✓ Process termination (exit syscall)

  • ❏ Signal handling (signal syscalls)

  • ❏ User-mode ring 3 execution

  • ✓ Kernel-mode execution

  • ❏ User/kernel mode switching

Filesystem

  • ✓ FAT filesystem read/write (basic done)

  • ✓ FAT_Create() - create new files

  • ✓ FAT_Delete() - delete files

  • ✓ Multi-cluster file support (files > 1 cluster)

  • ✓ Device files abstraction

  • ✓ File descriptors table per process

  • ❏ FAT_Stat() - file metadata

Terminal Support

  • ✓ TTY driver for /dev/tty0

  • ✓ Terminal line discipline (buffering, echo control)

  • ✓ ANSI escape sequence support

  • ✓ Keyboard input handling

  • ✓ Terminal control ioctl calls

Phase 2: Syscalls Wrappers

File I/O Syscalls

  • ✓ read - read from file descriptor

  • ✓ write - write to file descriptor

  • ✓ open - open file

  • ✓ close - close file descriptor

  • ✓ lseek - seek in file

  • ❏ fstat, stat, lstat - file metadata

  • ❏ ioctl - device control

  • ❏ fcntl - file control

  • ❏ access - check permissions

Memory Syscalls

  • ✓ brk - set data segment size (for malloc)

  • ❏ mmap, munmap - memory mapping

  • ❏ mprotect - set memory protection

  • ❏ mremap - remap memory region

Process Syscalls

  • ✓ exit - process termination

  • ❏ exit_group - process termination group

  • ✓ fork - process creation

  • ❏ clone - thread/process creation

  • ✓ execve - execute program

  • ❏ wait4, waitpid - wait for child process

  • ❏ getpid, getppid - process IDs

  • ❏ getuid, setuid - user IDs

  • ❏ geteuid, getgid, getegid - group IDs

Signal Syscalls

  • ❏ signal, sigaction - signal handlers

  • ❏ sigprocmask, sigpending - signal masking

  • ❏ kill - send signal

  • ❏ pause - wait for signal

  • ❏ alarm - timer signal

  • ❏ sigreturn - return from signal handler

Time Syscalls

  • ❏ time - current time

  • ❏ gettimeofday, clock_gettime - precise time

  • ❏ nanosleep - sleep

  • ❏ select, poll - I/O multiplexing

Miscellaneous Syscalls

  • ❏ uname - system info

  • ❏ getpagesize - page size

  • ❏ prctl - process control

  • ❏ umask - file creation mask

  • ❏ nice, getpriority, setpriority - scheduling

Phase 3: Advanced Features

Device Support

  • ✓ /dev/null device file

  • ✓ /dev/zero device file

  • ❏ /dev/random, /dev/urandom - entropy

  • ❏ Block device interface

  • ❏ Character device interface

  • ✓ Device node mounting

Filesystem Extended

  • ❏ Permission checking (uid/gid/mode)

  • ❏ Directory creation (mkdir)

  • ❏ Directory deletion (rmdir)

  • ❏ Symlink support

  • ❏ Hard link support

  • ❏ File ownership and chmod

Dynamic Linking

  • ✓ Custom dylib system (exists)

  • ✓ /lib, /usr/lib layouts (done)

  • ❏ LD_LIBRARY_PATH support

  • ❏ Symbol versioning

  • ❏ RPATH support

Networking

  • ❏ Socket syscalls (socket, bind, listen, connect, accept)

  • ❏ UDP/TCP support

  • ❏ DNS resolution

  • ❏ Network device drivers