Embedded Lua shell for Zephyr

[agguo]

My team (@alexayl, @agguo, @danjshaw) created a module which consists of an embedded Lua shell for Zephyr.

Overview

The project contains a Lua interpreter in a tailored shell-like environment, providing users with a module for rapid prototyping, testing, or debugging of their application.

The Lua peripheral library consists of wrappers around Zephyr's UART API which lets the peripherals be accessible via Lua scripts. Users can use the UART framework as a reference for creating custom commands that can be used at runtime to interact with their application. We’re hoping the community can also use the UART framework as a template for expanding the peripheral library with API wrapper layers around other peripherals supported by the zephyr ecosystem (our group only has access to the UART device through the RISCV emulated development board).

There are a few functions (e.g., _times(), _unlink()) that are not implemented in newlibc and picolibc but are necessary to build Lua. These are declared in an auxiliary C file for now.

Project with sample scripts can be found here: https://github.com/agguo/lsh/

Notes

There seemed to be some interest in integrating Lua a few years ago:

• Module request: Lua #47301
• Add POSIX times() support #51978

Curious whether there is still any interest in embedding Lua into Zephyr as an external module?