namespace System.Reactive.Linq.ObservableImpl { internal sealed class Synchronize<TSource> : Producer<TSource, Synchronize<TSource>._> { internal sealed class _ : Sink<TSource>, IObserver<TSource> { private readonly object _gate; public _(object gate, IObserver<TSource> observer, IDisposable cancel) : base(observer, cancel) { _gate = (gate ?? new object()); } public void OnNext(TSource value) { lock (_gate) { _observer.OnNext(value); } } public void OnError(Exception error) { lock (_gate) { _observer.OnError(error); base.Dispose(); } } public void OnCompleted() { lock (_gate) { _observer.OnCompleted(); base.Dispose(); } } } private readonly IObservable<TSource> _source; private readonly object _gate; public Synchronize(IObservable<TSource> source, object gate) { _source = source; _gate = gate; } public Synchronize(IObservable<TSource> source) { _source = source; } protected override _ CreateSink(IObserver<TSource> observer, IDisposable cancel) { return new _(_gate, observer, cancel); } protected override IDisposable Run(_ sink) { return _source.Subscribe(sink); } } }