sena-mike/swift-longhair

Usage

1) Add the package

Swift Package Manager (Package.swift)

dependencies: [
  .package(url: "https://github.com/swift-longhair/swift-longhair.git", from: "1.0.0")
]

Then add Longhair to your target dependencies.

Xcode

1. Add this package to your Xcode project by going to File > Add Packages... and entering the URL of this repository.
2. In Xcode project settings pre-processor macros for your target, add GF256_TARGET_MOBILE=1.

2) Encode blocks and recover missing data

The example below is mirrored by a test in Tests/LonghairTests/LonghairTests.swift (verifyReadmeUsageExample) to keep documentation usage validated.

import Foundation
import Longhair

let original = Data((0..<1024).map { UInt8($0 & 0xFF) })
let blockSize = 128
let recoveryBlockCount = 2

let dataBlocks = stride(from: 0, to: original.count, by: blockSize).map { start in
  original.subdata(in: start..<(start + blockSize))
}

var encoded = try Cauchy256.encode(
  dataBlocks: dataBlocks,
  recoveryBlockCount: recoveryBlockCount
)

// Simulate packet loss (up to recoveryBlockCount blocks)
encoded[2].data = nil
encoded[6].data = nil

let recovered = try Cauchy256.decode(
  blocks: encoded,
  recoveryBlockCount: Int32(recoveryBlockCount)
)

assert(recovered == original)

Local setup

Run the setup script to initialize the Longhair submodule and apply local overlay files (module.modulemap and CLonghair.apinotes):

./scripts/setup.sh

If you resync submodules later, re-apply overlays with:

./scripts/sync-clonghair-overlay.sh

Build and run tests:

swift build
swift test

Style checks

Format Swift code:

./scripts/swift-style.sh format

Lint Swift code:

./scripts/swift-style.sh lint

Verify formatting exactly (used in CI):

./scripts/swift-style.sh check

The formatter configuration is in .swift-format and uses 2-space indentation.

Package Metadata

Repository: sena-mike/swift-longhair

Default branch: main

README: README.md