AsyncReaderWriterLock 1.0.2

AsyncReaderWriterLock

A lightweight, cross-platform asynchronous reader‑writer lock for .NET with sync/async support, cancellation, and fair queuing.

dotnet add package AsyncReaderWriterLock

• Package: nuget.org/packages/AsyncReaderWriterLock
• Version: 1.0.2 | .NET 5+ | .NET Standard 2.0
• Developer: Lonewolf239

Features

Quick Start

Acquiring a read lock

using AsyncLocks;

var rwLock = new AsyncReaderWriterLock();

using (var releaser = rwLock.ReadLock())
{
    // Multiple threads can read concurrently
    Console.WriteLine("Reading protected data...");
}

Acquiring a write lock

using (var releaser = rwLock.WriteLock())
{
    // Only one writer at a time
    Console.WriteLine("Writing exclusive data...");
}

Asynchronous usage

// Async read lock
using (var releaser = await rwLock.ReadLockAsync())
{
    await Task.Delay(100);
    Console.WriteLine("Async read lock acquired");
}

// Async write lock with cancellation
var cts = new CancellationTokenSource(500);
try
{
    using (var releaser = await rwLock.WriteLockAsync(cts.Token))
    {
        Console.WriteLine("Async write lock acquired");
    }
}
catch (OperationCanceledException)
{
    Console.WriteLine("Lock acquisition was canceled");
}

Disposal

The lock implements IDisposable. Dispose it when no longer needed to release all waiting threads and free resources.

using var rwLock = new AsyncReaderWriterLock();
// ... use lock

Advanced Usage

Nesting locks

The lock does not support recursive acquisition. Attempting to acquire the same lock again from the same thread will result in a deadlock or SynchronizationLockException (for write→write or write→read). Always design your code to avoid recursive locking.

Fairness

The lock is fair: waiting threads are served in the order they requested the lock. This prevents writer starvation.

Manual release

The Releaser returned by ReadLock()/WriteLock() is a struct that releases the lock when disposed. You can store it and release later, but ensure proper disposal to avoid deadlocks.

API Reference

Full method reference — API.md

Contributing

We welcome contributions! Please see CONTRIBUTING.md for guidelines.

Philosophy

Simple, reliable, thread‑safe. AsyncReaderWriterLock provides just the synchronization primitive you need — nothing more, nothing less. The API is minimal but powerful, and the implementation is thoroughly tested to ensure correctness under all circumstances.