async-lock

An awaitable semaphore class for the .NET's TPL library which can be used similar to the conventional lock block.

The lock block is mimicked by the using(await ...)construct, so you can await entering the critical section in your asynchronous method.

Solution

Under the hood there are SemaphoreSlim instances are being used for synchronization, which is wrapped in a disposable class, see and build the source code with the given Visual Studio 2015 solution. The tests are using Moq and MSPEC.

Usage examples

You can create many AsyncLock instances if needed:

private AsyncLock Lock = new AsyncLock();

var token = new object();

using(await Lock.AcquireAsync(token)) {
  // critical section
}

Or use the singleton version across your application:

using(await AsyncLock.CreateAsync(token)) {
  // critical section
}

Remarks

You can also use the synchronous version of both examples - without the 'Async' postfixes.