https://github.com/firechip/cobs_codec_swift

Pure-Swift, dependency-free Consistent Overhead Byte Stuffing (COBS) and COBS/R codec (Swift Package Manager). The Swift member of the Firechip COBS family.
https://github.com/firechip/cobs_codec_swift

byte-stuffing cobs cobs-r encoding framing macos serial spm swift swift-package-manager

Last synced: about 8 hours ago
JSON representation

Pure-Swift, dependency-free Consistent Overhead Byte Stuffing (COBS) and COBS/R codec (Swift Package Manager). The Swift member of the Firechip COBS family.

• Host: GitHub
• URL: https://github.com/firechip/cobs_codec_swift
• Owner: firechip
• License: mit
• Created: 2026-07-04T20:52:48.000Z (about 11 hours ago)
• Default Branch: main
• Last Pushed: 2026-07-04T21:47:38.000Z (about 10 hours ago)
• Last Synced: 2026-07-04T23:08:31.740Z (about 9 hours ago)
• Topics: byte-stuffing, cobs, cobs-r, encoding, framing, macos, serial, spm, swift, swift-package-manager
• Language: Swift
• Size: 28.3 KB
• Stars: 1
• Watchers: 0
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • Changelog: CHANGELOG.md
  • Contributing: CONTRIBUTING.md
  • License: LICENSE

Awesome Lists containing this project

README

          
# CobsCodec

[![CI](https://github.com/firechip/cobs_codec_swift/actions/workflows/ci.yml/badge.svg)](https://github.com/firechip/cobs_codec_swift/actions/workflows/ci.yml)

[![Swift 6](https://img.shields.io/badge/swift-6-orange.svg)](https://swift.org)

[![Platforms](https://img.shields.io/badge/platforms-macOS%20%7C%20iOS%20%7C%20Linux-lightgrey.svg)](#)

[![License: MIT](https://img.shields.io/badge/license-MIT-blue.svg)](LICENSE)

Pure-Swift **Consistent Overhead Byte Stuffing (COBS)** and **COBS/R** codec — the

Swift member of the Firechip COBS family (alongside the

[Rust](https://crates.io/crates/cobs_codec_rs),

[Dart](https://pub.dev/packages/cobs_codec) and

[Kotlin](https://github.com/firechip/cobs_codec_kt) implementations), verified

byte-identical against the shared

[conformance vectors](https://github.com/firechip/cobs-conformance).

COBS encodes an arbitrary byte sequence into one that contains no zero (`0x00`)

byte, at a small, predictable cost (at most one extra byte per 254 bytes, plus

one). A single `0x00` can then reliably delimit packets on a serial/UART, USB, or

BLE link. The `CobsCodec` library is **Swift-standard-library-only** — no

Foundation, no Apple frameworks, no dependencies — so it runs on macOS, iOS,

tvOS, watchOS, and Linux (and embedded Swift).

## Install

Swift Package Manager — add the dependency to your `Package.swift`:

```swift

dependencies: [

    .package(url: "https://github.com/firechip/cobs_codec_swift.git", from: "1.0.0"),

],

targets: [

    .target(name: "YourTarget", dependencies: ["CobsCodec"]),

]

```

Or in Xcode: **File ▸ Add Package Dependencies…** and paste the repository URL.

## Usage

```swift

import CobsCodec

// Encode / decode a single packet.

let encoded = Cobs.encode([0x11, 0x22, 0x00, 0x33]) // [0x03, 0x11, 0x22, 0x02, 0x33] — no 0x00

let decoded = try Cobs.decode(encoded)              // [0x11, 0x22, 0x00, 0x33]

// COBS/R often saves the trailing overhead byte for small messages.

Cobsr.encode(Array("12345".utf8))                   // [0x35, 0x31, 0x32, 0x33, 0x34] — "51234"

// A custom delimiter byte (sentinel): the output avoids it, so it can delimit

// frames instead of 0x00. `sentinel: 0` is identical to the plain codec.

let stuffed = Cobs.encode([0x11, 0x00, 0x22], sentinel: 0xAA) // [0xA8, 0xBB, 0xA8, 0x88] — no 0xAA

try Cobs.decode(stuffed, sentinel: 0xAA)                      // [0x11, 0x00, 0x22]

// Decode in place, without a second buffer (COBS never expands on decode).

var buffer = Cobs.encode([0x11, 0x00, 0x22])

let n = try Cobs.decodeInPlace(&buffer)             // n == 3; buffer[0..