Daniel Samson
2ab0d129a2
The flat analog of pci-class for acpi_device nodes. ACPI has no class/subclass/prog-IF
taxonomy — a device's identity is its _HID string itself (PNP0303 *is* "PS/2
keyboard") — so this is a plain id -> name registry, not a hierarchical decoder.
New system/devices/acpi-ids.zig (module `acpi-ids`): the common standard PnP/ACPI
hardware IDs; vendor-specific ids (QEMU0002, etc.) have no registry name and print the
raw HID. Shared reference data like pci-class. The dump now names each _HID:
KBD_ [acpi_device] hid=PNP0303 (PS/2 Keyboard)
COM1 [acpi_device] hid=PNP0501 (16550A-compatible Serial Port)
RTC_ [acpi_device] hid=PNP0B00 (Real-Time Clock (RTC))
LNKA [acpi_device] hid=PNP0C0F (PCI Interrupt Link Device)
FWCF [acpi_device] hid=QEMU0002 (vendor-specific: raw HID)
Host test covers known ids and the unknown/empty fallthrough. Suite 41/41 plus host
tests.
DanOS
Codename: Shodan Version: 1
A small operating system, written from scratch in Zig — a bootloader (boot/)
and a microkernel (system/kernel/), sharing a neutral handoff contract (system/boot-handoff.zig).
It boots x86-64 via UEFI, and so far has a framebuffer console, a physical frame
allocator, its own paging with W^X permissions, interrupt/exception handling, a
LAPIC timer, a kernel heap, a fixed-priority preemptive scheduler, and in-kernel IPC
channels. See docs/ for how each piece works.
Prerequisites
- Zig 0.16.x — the build is pinned to this line (
.zig-version); other minor versions are rejected, because Zig makes breaking changes between releases pre-1.0. A toolchain manager such as zvm orzigupwill pick up.zig-versionautomatically. - QEMU (
qemu-system-x86_64) — to run and test the kernel. On macOS,brew install qemualso bundles the OVMF firmware below. - OVMF UEFI firmware — the
edk2-ovmfpackage (Arch),ovmf(Debian/Ubuntu), oredk2-ovmf(Fedora); on macOS it ships inside the Homebrewqemuformula. Both the build and the test harness probe the known Arch/Debian/Fedora/macOS layouts and use the first that exists, so no configuration is normally needed. Override with-Dovmf-code=/-Dovmf-vars=(build) if yours lives elsewhere. - Python 3 — for the QEMU integration test harness.
Build
zig build
Produces a FHS-shaped zig-out/ that is the danos filesystem and the boot volume:
the UEFI bootloader at zig-out/EFI/BOOT/BOOTX64.efi, the kernel at
zig-out/system/kernel, init at zig-out/system/services/init, drivers under
zig-out/system/drivers/, and the initial-ramdisk at zig-out/boot/.
Run
Boot it in QEMU with OVMF (opens a display window):
zig build run-x86-64
# distro with OVMF elsewhere:
zig build run-x86-64 -Dovmf-code=/path/OVMF_CODE.fd -Dovmf-vars=/path/OVMF_VARS.fd
Test
zig build test # host unit tests (the platform-independent shared code)
python3 test/qemu_test.py # QEMU integration tests: boots the kernel and asserts
# on its serial output (see docs/testing.md)
The integration harness builds and boots the kernel once per test case, checking memory, the frame allocator, paging (incl. NX and the null guard), the heap, interrupts, and exception handling. It exits non-zero on any failure, so it drops straight into CI.
Documentation
Design notes explaining the why behind the code live in
docs/ — start with docs/README.md.
Logo
San Serif Text "Dan OS" with a black karate belt around it.