DM_SW_RING - DMOD Software Ring Buffer Module

A DMOD (Dynamic Modular System) module providing a general-purpose software ring buffer (circular buffer) implementation for embedded systems.

Features

• Byte-level Ring Buffer: Stores arbitrary binary data byte-by-byte with configurable capacity
• Overwrite Mode: Optionally discard oldest data when the buffer is full (dm_sw_ring_flags_drop_old_data)
• Thread Safety: Optional mutex-based synchronization for use in multi-threaded environments (dm_sw_ring_flags_mutex_sync)
• Blocking Writes: Optionally block a writer until space becomes available (dm_sw_ring_flags_wait_for_space)
• Blocking Reads: Optionally block a reader until at least some data is available (dm_sw_ring_flags_wait_for_some_data) or until all requested data is available (dm_sw_ring_flags_wait_for_all_data)
• Non-destructive Peek: Inspect buffered data without consuming it
• Discard and Clear: Remove data from the buffer without reading it
• DMOD Integration: Follows the DMOD module lifecycle (dmod_init / dmod_deinit)

Quick Start

Installation

Using dmf-get from the DMOD release package:

dmf-get install dm_sw_ring

Basic Usage

#include "dm_sw_ring.h"

// Create a 64-byte ring buffer with default settings
dm_sw_ring_t ring = dm_sw_ring_create(64, dm_sw_ring_flags_default);

// Write data
uint8_t tx[] = {1, 2, 3, 4};
dm_sw_ring_capacity_t written = dm_sw_ring_write(ring, tx, sizeof(tx));

// Read data
uint8_t rx[4];
dm_sw_ring_capacity_t read = dm_sw_ring_read(ring, rx, sizeof(rx));

// Destroy when done
dm_sw_ring_destroy(ring);

Building

Prerequisites

• CMake 3.18 or higher
• C99-compatible compiler
• DMOD framework (automatically fetched via CMake FetchContent)

Build Commands

# Configure
cmake -B build

# Build
cmake --build build

Documentation

Comprehensive documentation is available in the docs/ directory:

• dm_sw_ring.md - Module overview and architecture
• api-reference.md - Complete API documentation
• examples.md - Usage examples

View documentation using dmf-man:

dmf-man dm_sw_ring          # Main documentation
dmf-man dm_sw_ring api      # API reference
dmf-man dm_sw_ring examples # Usage examples

Project Structure

dm_sw_ring/
├── docs/              # Documentation (markdown format)
├── include/           # Public headers
│   └── dm_sw_ring.h  # Main API (types, flags, function declarations)
├── src/
│   └── dm_sw_ring.c  # Core implementation
├── tests/
│   ├── CMakeLists.txt         # Test build configuration
│   └── test_dm_sw_ring.c      # Unit tests
├── CMakeLists.txt    # Build configuration
├── dm_sw_ring.dmr    # DMOD resource file
└── manifest.dmm      # DMOD manifest

Contributing

Contributions are welcome! Please:

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Submit a pull request

License

This project is licensed under the MIT License - see the LICENSE file for details.

Authors

• Patryk Kubiak - Initial work

Related Projects

• DMOD - Dynamic Modular System framework
• DMGPIO - DMOD GPIO Driver Module
• DMHAMAN - DMOD Handler Manager

Support

For issues, questions, or contributions:

• Open an issue on GitHub
• Check the documentation in docs/
• Use dmf-man dm_sw_ring for command-line help