Keyronex is a hobby operating system. It makes no pretences to be anything novel or exciting, and doesn't do anything likely to be interesting to anyone.
The long-term goal is to build a fairly competent operating system by the standards of the early 90s, with as much scalability and as many mod-cons as is reasonably possible for a single person to implement. The system combines technical influences from both the Unix tradition (particularly Mach/NeXTSTEP, NetBSD, and Solaris) with influences from the VMS tradition (particularly OpenVMS itself, Mintia, and Windows NT). Special attention has been given to the virtual memory system.
Keyronex is a portable system. Supported platforms are summarised below; more detailed information is available in the Platforms document.
| Platform | Architecture | Status |
|---|---|---|
| ACPI 64-bit PC | amd64 | Well-supported |
| ACPI AArch64 | aarch64 | Poorly supported1 |
| ACPI RISC-V 64 | riscv64 | Partly supported2 |
| Amiga | m68k | Planned |
| QEMU Virt m68k | m68k | Well-supported |
Some manual pages for the kernel have been written. An introduction to the kernel manual pages section can be found at the Introduction.
[ This is a rewrite branch which currently lacks features; the previous, more
featured branch is 23-jul, which features ports of such apps as the GNU
Coreutils, BASH shell, Binutils, and GCC, as well as Xorg and some basic X11
apps such as Twm and Xeyes, and the Links text-mode web browser. ]
In kernel mode, a rough distinction can be drawn between the kernel, executive services, and the driver framework. This is a non-inclusive list of the features of Keyronex:
-
Kernel
- Interrupt management with Priority Level (IPL) and soft interrupts (DPCs).
- Waiting/synchronisation objects, including waiting on multiple of these.
- Remote-Copy-Update (RCU) mechanism.
- Time management.
- Process/thread distinction with pre-emptive scheduling of threads.
- Kernel Ports, an efficient basis for message queues.
- (incomplete) Balance set management.
-
Virtual Memory
- Bundy resident page-frame allocator with page stealing.
- Demand-paged anonymous and file-backed memory.
- Working set-based local page replacement.
- Page-out of anonymous and file pages, including page tables themselves.
- Mapped file cache for coherent cached read/write of files.
- VM "Fork" operation.
- (not yet started) Proactive writeback for cached files.
- (incomplete) Kernel paged heap allocation.
- (incomplete) Global 2nd-chance page queues with balancing and writeback.
-
Executive Services
- Futexes.
- Virtual Filesystem Switch.
- Namecache, including "NullFS" (bind mount) support.
- Object-oriented, handle-based userland interface.
- Executive Poll (EPoll), a readiness-notification API.
- (not yet started) File write-behind
- (not yet started) Native IPC mechanism
-
Driver Support Services:
- Objective-C driver framework.
- Profoundly asynchronous system of I/O Packet (IOP) message-based I/O.
- (incomplete) STREAMS framework for asynchronous character I/O.
-
Drivers & Filesystems
- ACPI-based device discovery.
- VirtIO drivers: Disk, basic GPU, NIC, and 9p port.
- xHCI driver and beginnings of USB stack.
- Intel E1000 NIC driver.
- PS/2 keyboard.
- (incomplete) Windows "StorPort" driver shim.
- (incomplete) FAT, Ext2 filesystems..
- (incomplete) 9p filesystem (both VirtIO and TCP transport).
- (not yet started) Open Firmware/Device Tree based discovery.
-
Miscellaneous Kernel:
- (incomplete) Kernel debugging GDB port over UDP.
- (not yet started) STREAMS-based TCP/IP stack.
- (not yet started) Extended Berkeley Packet Filter (e-BPF).
-
POSIX subsystem server:
- (not yet started) Processes, process groups, sessions, TTYs, etc.
Several third-party components are used. These are some of them:
- Limine: The bootloader used for Keyronx on AArch64 and amd64.
- FreeBSD:
queue.handtree.h, generic type-safe list/queue and tree macros for C. - NetBSD:
- The Boldface font used on the Amiga port's PAC console.
- Reference for Amiga port and source of chipset register definition headers
cia.h,custom.h.
- mlibc: A portable C standard library. Provides the libc.
- nanoprintf: Printf implementation; provides
kprintfand family. - uACPI: The UltraOS ACPI Implementation from UltraOS. Used by the ACPI drivers.
- Various headers (mostly BSDs, some Linux): BSD-licenced headers mainly for device register definitions.
Code original to Keyronex is licenced under the Mozilla Public Licence v2.0
(MPLv2).
Other components are under their own licences, all of which are MPL compatible;
these are mostly under the BSD or similar licences.
See the vendor and subprojects folders where the licences of the third-party
components can be found.
To build Keyronex and all of the userspace you will need the following dependencies:
autopoint
gettext
git
gperf
help2man
libgmp-dev
libmpc-dev
libmpfr-dev
libtool
m4
meson (>= 0.57.0)
pkg-config
python3
python3-mako
python3-pip
texinfo
yacc
xbstrap
xorriso
These packages are gotten with apt install on Ubuntu, except for xbstrap,
which is gotten with pip install xbstrap.