LwUTIL latest-develop documentation

Welcome to the documentation for version latest-develop.

LwUTIL is a lightweight utility library that collects small helper macros and functions for value comparisons, bit manipulation, endian-aware serialization and a few common algorithms, commonly hand-written again and again in day-to-day C/C++ development.

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Features

  • Written in C (C11), compatible with stdint.h data types

  • Get the minimum or maximum of two values, constrain a value to a range, or map it between two ranges

  • Get the absolute value of a signed input

  • Silence “unused variable” compiler warnings

  • Dereference and assign through a pointer, but only when it is not NULL

  • Compute the number of elements in a statically allocated array, with LWUTIL_ASZ as a short alias

  • Store and load 16-bit and 32-bit values to and from a byte buffer, in little- or big-endian format

    • Pointer-advancing extended variants are available for sequential (de)serialization

  • Set, clear, toggle or check bits against a bit mask

  • Convert 8/16/32-bit values to their hexadecimal ASCII representation

  • Encode and decode 32-bit values in variable-length integer (varint) format

  • Check whether a time period has elapsed against a rolling time reference, useful for non-blocking periodic tasks

  • Calculate a rolling (sliding-window) linear regression slope over fixed-step sample data, with helpers to query window capacity/count and reset it

  • Assert an expression at compile time

  • No dynamic memory allocation

  • User friendly MIT license

Requirements

  • C compiler

  • Negligible flash and RAM footprint - only the functions you actually call get linked

Contribute

Fresh contributions are always welcome. Simple instructions to proceed:

  1. Fork Github repository

  2. Respect C style & coding rules used by the library

  3. Create a pull request to develop branch with new features or bug fixes

Alternatively you may:

  1. Report a bug

  2. Ask for a feature request

License

MIT License

Copyright (c) 2026 Tilen MAJERLE

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.