roOs - Kernel

• roOs is a kernel created for training and educational purposes. It is the result of multiple hours of work to better understand the underlying concepts related to operating systems.
• The kernel is designed around real-time operating systems concepts and will not be intended to perform as a general-purpose operating system.

Build status

Status	Main	Dev
CI
Codacy

Supported Architectures

i386	x64
Status Work in Progress	Status Work in Progress
Supported Processing Multicore, Singlecore	Supported Processing Multicore, Singlecore
Supported Drivers PIC IO-APIC Local APIC ACPI Serial Ports RTC PIT Local APIC Timers TSC VGA Text 80x25 Generic PS/2 Keyboard	Supported Drivers PIC IO-APIC Local APIC ACPI Serial Ports RTC PIT Local APIC Timers TSC VGA Text 80x25 Generic PS/2 Keyboard

Supported General Features

File Device Tree

• FDT is used to setup the system and discover drivers
• FDT handles used for drivers inter-operability
• Configuration (stdin, stdout, interrupts, etc.) in FDT

Driver Management

• Easy-to-use driver system
• Driver attach mechanism with FDT auto-discovery

Memory Management

• Higher-half kernel
• Virtual and Physical memory allocator
• Kernel Heap allocator

Interrupt and Exception Management

• Custom Interrupts
• Custom Exceptions

Synchronization

• Futex based synchronization
• Mutex: Non recursive/Recursive - Priority inheritance capable - FIFO and Priority-based queuing disciplines.
• Semaphore: FIFO and Priority-based queuing disciplines - Counting and Binary semaphores.
• Spinlocks
• Kernel critical section by disabling interrupts

Communication

• Signals, not really POSIX signals but still signals
• Inter-processor interrupts

Scheduler

• Priority based scheduler (Round Robin for all the threads having the same priority)
• Kernel threads
• Updateable priorities
• Sleep capable

Libraries

• Embedded LibC
• Structures Libraries (Vector, HashTable, Queues, etc.)

Virtual File System

• Character-based driver support

Roadmap

You can see the planned tasks / features in the project's kanban on GitHub: https://github.com/users/Oxmose/projects/2

Testing

roOs has a test suite allowing extensible testing. Using internal memory test buffers, the testing framework allows validating the system's correct behavior. Tests can be added as new features are developed.

Build and Run

To build roOs, choose the architecture you want and execute. Architecture list to use in the TARGET flag:

• x86_i386
• x86_64

Compilation

make target=[TARGET] TESTS=[TRUE/FALSE] DEBUG=[TRUE/FALSE] TRACE=[TRUE/FALSE]

Execution

make target=[TARGET] run

Tests, Trace and Debug

• TESTS flag set to TRUE to enable internal testing
• DEBUG flag set to TRUE to enable debuging support (-O0 -g3)
• TRACE flag set to TRUE to enable kernel tracing