ScrollGestureRecognizer crashes long running application on 32-bit Linux

[ondrejsusovsky]

Describe the bug

When interacting with long running (25+ days) application on 32-bit Linux I get OverflowException with following stacktrace:

System.Private.CoreLib
   at System.OverflowException..ctor(String message)
   at System.TimeSpan.IntervalFromDoubleTicks(Double ticks)
   at Avalonia.Input.GestureRecognizers.ScrollGestureRecognizer.PointerPressed(PointerPressedEventArgs e)
   at Avalonia.Input.GestureRecognizers.GestureRecognizerCollection.HandlePointerPressed(PointerPressedEventArgs e)
   at Avalonia.Input.InputElement.<>c.<.cctor>b__32_13(InputElement x, PointerPressedEventArgs e)
   at Avalonia.Reactive.LightweightObservableBase`1.PublishNext(T value)
   at Avalonia.Interactivity.EventRoute.RaiseEventImpl(RoutedEventArgs e)
   at Avalonia.Interactivity.EventRoute.RaiseEvent(Interactive source, RoutedEventArgs e)
   at Avalonia.Interactivity.Interactive.RaiseEvent(RoutedEventArgs e)
   at Avalonia.Input.TouchDevice.ProcessRawEvent(RawInputEventArgs ev)
   at Avalonia.Controls.TopLevel.<>c.<HandleInput>b__150_0(Object state)
   at Avalonia.Threading.Dispatcher.Send(SendOrPostCallback action, Object arg, Nullable`1 priority)
   at Avalonia.Controls.TopLevel.HandleInput(RawInputEventArgs e)
   at Avalonia.ManualRawEventGrouperDispatchQueue.DispatchNext()
   at Avalonia.X11.X11PlatformThreading.RunLoop(CancellationToken cancellationToken)
   at Avalonia.Threading.DispatcherFrame.Run(IControlledDispatcherImpl impl)
   at Avalonia.Threading.Dispatcher.PushFrame(DispatcherFrame frame)
   at Avalonia.Threading.Dispatcher.MainLoop(CancellationToken cancellationToken)
   at Avalonia.Controls.ApplicationLifetimes.ClassicDesktopStyleApplicationLifetime.StartCore(String[] args)
   at Avalonia.ClassicDesktopStyleApplicationLifetimeExtensions.StartWithClassicDesktopLifetime(AppBuilder builder, String[] args, Action`1 lifetimeBuilder)
   at Appl.Program.Main(String[] args) 

To Reproduce

Let application containing ScrollGestureRecognizer run for 25 days and interact with it. Or pass events containing large enough timestamps to the ScrollGestureRecognizer.

Expected behavior

Not crash

Avalonia version

11.2.x, but looking at the code it should affect master also

OS

Linux

Additional context

Looking at it closer, it's two issues in one:

1. Input event timestamps overflow after ~25 days, and negative values are converted to large ulong values
   

   Avalonia/src/Avalonia.X11/XI2Manager.cs

   Line 560 in f13bfe6

   Timestamp = (ulong)ev->time.ToInt64();

2. Timestamps are converted to TimeSpans, which have limited range that doesn't allow these large overflowed UInt64 values
   

   Avalonia/src/Avalonia.Base/Input/GestureRecognizers/ScrollGestureRecognizer.cs

   Line 115 in f13bfe6

   _velocityTracker?.AddPosition(TimeSpan.FromMilliseconds(e.Timestamp), default);

[timunie]

If anyone has a better idea, propose changes as a PR. I cannot guarantee that it will be merged but it's good to see options

[ThadHouse]

Digging through, it looks like treating it as signed is incorrect, as every definition I can find treats the value as unsigned. Fixing that sould be easy (Change to UIntPtr instead of IntPtr), and will fix the crash, along with moving the rollover out to 50 days.

However, what does the gesture handler do if a rollover occurs while a gesture is occuring?