Simple/Demonstration extension method to provide async/await on top of IVI VISA IMessageBasedRawIO Read APIs

RawIOReadExtensions.cs

namespace Ivi.Visa;

public static class RawIOReadExtensions
{
    public static async ValueTask ReadAsync(
        this IMessageBasedRawIO io,
        byte[] buffer,
        long index = 0,
        long count = -1,
        CancellationToken cancellationToken = default)
    {
        cancellationToken.ThrowIfCancellationRequested();

        TaskCompletionSource completionSource = new();
        var asyncResult = io.BeginRead(buffer, index, count, OnReadComplete, null);

        var canBeCanceled = cancellationToken.CanBeCanceled && !asyncResult.CompletedSynchronously;
        using CancellationTokenRegistration registration = canBeCanceled
            ? cancellationToken.Register(() => io.AbortAsyncOperation(asyncResult))
            : default;

        await completionSource.Task;

        void OnReadComplete(IVisaAsyncResult result)
        {
            io.EndRead(result);
            if (result.IsAborted)
            {
                completionSource.SetCanceled(cancellationToken);
            }
            else
            {
                completionSource.SetResult();
            }
        }
    }
}