dmosal — OS Abstraction Layer

A small, portable embedded C abstraction layer providing deterministic/bounded resource management and consistent concurrency, timing, and communication semantics across POSIX and RTOS platforms.

Everything (tasks, mutexes, semaphores, queues, timers, ...) is allocated statically up front through a central resource manager, so there's no malloc on the hot path and the worst-case memory usage is known ahead of time. A POSIX/Linux backend is included; other targets can be added behind the same API without breaking existing callers.

   +-------------------------------+
   |           Application         |
   +-------------------------------+
   +--------------+----------------+
   |       OSAL   |    libc        |
   +--------------+----------------+
   +-------------------------------+
   |        OS User Space APIs     |
   +-------------------------------+
   +-------------------------------+
   |         OS Kernel Space       |
   +-------------------------------+
   +-------------------------------+
   |            HW                 |
   +-------------------------------+

Getting started

You'll need cmake, libcmocka-dev, and doxygen:

sudo apt install cmake libcmocka-dev doxygen

Then build the library, run the tests, and check out the examples:

just check          # configure + build + run tests
just build           # build the examples target

If you'd rather not install a toolchain locally, there's a pinned Dockerfile:

docker build -t dmosal-dev .
docker run --rm -v "$PWD":/workspace -w /workspace dmosal-dev just check

Don't have just installed? Check the justfile — every recipe there is just a couple of plain cmake/ctest commands you can run directly.

There are a few more recipes worth knowing about: just check-valgrind, just check-asan, just check-tsan, just check-coverage, just doc, just format, just tidy. Run just --list to see everything.

Resource limits (how many tasks, queues, etc. you get) are set at CMake configure time — see osal_config.cmake.

Examples

Sample programs live in examples/. Build them with just build (CMake target examples).

Documentation

• API reference (Doxygen): run just doc, output ends up in build/doc/html/.
• Design docs: docs/ — architecture, API spec, resource lifetime, thread-safety, porting guide.

Contributing

Bug reports, patches, ideas — all welcome. See CONTRIBUTING.md for how to build, test, and keep the style consistent.

License

BSD-2-Clause — see LICENSE.