UMKa -- User-Mode KolibriOS developer tools

This is a common project for a set of KolibriOS developer tools which are based on original KolibriOS kernel code wrapped and hacked as to run in the UNIX programming environment. The idea is to make userspace UNIX tools that use as much unchanged KolibriOS kernel source as possible to run, test and debug architecture-independent parts of the kernel in your favorite developer environment.

What works now:

• block layer (disk, cache, partition, MBR, GPT),
• file systems except iso9660 (fat*, exfat, ext*, xfs),
• UI and graphics (geometric primitives, windows, winmap, cursors),
• basic network (configuration, ping replies),
• interrupts (via signals),
• threads and processes,
• scheduler,
• slab allocator,
• events,
• synchronization primitives,
• unpacker,
• string functions,
• other minor functions.

umka_shell

is an interactive shell with commands that are wrappers around KolibriOS kernel syscalls and other internal functions. It can also be used for automated testing by feeding it a file of commands instead of typing them.

Example: $ umka_shell < mytest.t

umka_fuse

is like umka_shell above but commands are translated from FUSE calls, not entered manually or read from a file. Can potentially be used to run xfstests (cross-fs-tests) and automated tests against reference FS implementation.

umka_os

is KolibriOS kernel running main loop (osloop), scheduler and all the threads including network stack.

tools

mkdirrange - make directories with names in range

mkfilepattern - make a file with contents of specific pattern

BUILD

Linux:

$ KOLIBRIOS=/path/to/kolibrios HOST=linux CC=gcc make

/path/to/kolibrios is where you checked out 'svn co svn://kolibrios.org'.

Windows:

Same but specify HOST=windows and your favourite C compiler.

Architecture

Kernel services are replaced with stubs, wrappers around userspace implementation or libc calls. Block devices are emulated with regular files. Framebuffer can be dumped to disk as image file.

Testing

Run all the tests

$ HOST=linux make -B

Copy ACPI tables and PCI configs

# cp --parents /sys/firmware/acpi/tables/?SDT* /sys/bus/pci/devices/*/config .

Manage tap device

# ip tuntap add dev tap0 mode tap
# ip link set tap0 address 00:11:00:00:00:00
# ip addr add 10.50.0.1/24 dev tap0
# ip link set up dev tap0
# ip tuntap del dev tap0 mode tap

Troubleshooting

umka_os

To create tap devices.

# setcap cap_net_admin+ep umka_os

To load apps at 0 address.

# sysctl -w vm.mmap_min_addr=0

Allow reading process_vm_readv syscall.

# sysctl -w kernel.yama.ptrace_scope=0

Insert msr linux kernel module to collect coverage.

# modprobe msr

Links & Acknowledgements

[1] Filesystem in Userspace https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/fs/fuse

[2] Filesystem in Userspace library https://github.com/libfuse/libfuse

[3] LodePNG by Lode Vandevenne https://lodev.org/lodepng/

[4] Optparse by Christopher Wellons https://github.com/skeeto/optparse

[5] Universal TUN/TAP device driver by Maxim Krasnyansky and others https://www.kernel.org/doc/html/v5.12/networking/tuntap.html

[6] Isocline by Daan Leijen https://github.com/daanx/isocline

[7] em_inflate by Emmanuel Marty https://github.com/emmanuel-marty/em_inflate

[8] qemu-nbd by Anthony Liguori and others https://www.qemu.org/docs/master/tools/qemu-nbd.html

[9] Simple DirectMedia Layer library aka SDL2 https://libsdl.org