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using System.Runtime.InteropServices;
using System.Windows.Input;
using System.Windows.Input.StylusWisp;
using System.Windows.Media;
using System.Windows.Threading;
using System.Diagnostics;
using MS.Win32;
using MS.Internal;
using MS.Internal.Interop;
using MS.Internal.PresentationCore; // SecurityHelper
using MS.Utility;
using System.Security;
using System.Security.Permissions;
using SR=MS.Internal.PresentationCore.SR;
using SRID=MS.Internal.PresentationCore.SRID;
namespace System.Windows.Interop
{
/////////////////////////////////////////////////////////////////////////
internal sealed class HwndStylusInputProvider : DispatcherObject, IStylusInputProvider
{
private const uint TABLET_PRESSANDHOLD_DISABLED = 0x00000001;
private const uint TABLET_TAPFEEDBACK_DISABLED = 0x00000008;
private const uint TABLET_TOUCHUI_FORCEON = 0x00000100;
private const uint TABLET_TOUCHUI_FORCEOFF = 0x00000200;
private const uint TABLET_FLICKS_DISABLED = 0x00010000;
private const int MultiTouchEnabledFlag = 0x01000000;
/////////////////////////////////////////////////////////////////////
/// <SecurityNote>
/// Accesses and stores critical data (_site, _source, _stylusLogic).
/// </SecurityNote>
[SecurityCritical]
internal HwndStylusInputProvider(HwndSource source)
{
InputManager inputManager = InputManager.Current;
_stylusLogic = new SecurityCriticalDataClass<WispLogic>(StylusLogic.GetCurrentStylusLogicAs<WispLogic>());
IntPtr sourceHandle;
(new UIPermission(PermissionState.Unrestricted)).Assert();
try //Blessed Assert this is for RegisterInputManager and RegisterHwndforinput
{
// Register ourselves as an input provider with the input manager.
_site = new SecurityCriticalDataClass<InputProviderSite>(inputManager.RegisterInputProvider(this));
sourceHandle = source.Handle;
}
finally
{
UIPermission.RevertAssert();
}
_stylusLogic.Value.RegisterHwndForInput(inputManager, source);
_source = new SecurityCriticalDataClass<HwndSource>(source);
// Enables multi-touch input
UnsafeNativeMethods.SetProp(new HandleRef(this, sourceHandle), "MicrosoftTabletPenServiceProperty", new HandleRef(null, new IntPtr(MultiTouchEnabledFlag)));
}
/////////////////////////////////////////////////////////////////////
/// <SecurityNote>
/// Critical:This class accesses critical data, _site
/// TreatAsSafe: This class does not expose the critical data.
/// </SecurityNote>
[SecurityCritical,SecurityTreatAsSafe]
public void Dispose()
{
if(_site != null)
{
_site.Value.Dispose();
_site = null;
_stylusLogic.Value.UnRegisterHwndForInput(_source.Value);
_stylusLogic = null;
_source = null;
}
}
/////////////////////////////////////////////////////////////////////
/// <SecurityNote>
/// Critical: This method acceses critical data hwndsource
/// TreatAsSafe:Information about whether a given input provider services
/// a visual is safe to expose. This method does not expose the critical data either.
/// </SecurityNote>
[SecurityCritical,SecurityTreatAsSafe]
bool IInputProvider.ProvidesInputForRootVisual(Visual v)
{
Debug.Assert( null != _source );
return _source.Value.RootVisual == v;
}
void IInputProvider.NotifyDeactivate() {}
/////////////////////////////////////////////////////////////////////
//[CodeAnalysis("AptcaMethodsShouldOnlyCallAptcaMethods")] //Tracking Bug: 29647
/// <SecurityNote>
/// Critical: This code is critical since it handles all stylus messages and could be used to spoof input
/// </SecurityNote>
[SecurityCritical]
IntPtr IStylusInputProvider.FilterMessage(IntPtr hwnd, WindowMessage msg, IntPtr wParam, IntPtr lParam, ref bool handled)
{
IntPtr result = IntPtr.Zero ;
// It is possible to be re-entered during disposal. Just return.
if(null == _source || null == _source.Value)
{
return result;
}
switch(msg)
{
case WindowMessage.WM_ENABLE:
_stylusLogic.Value.OnWindowEnableChanged(hwnd, (int)NativeMethods.IntPtrToInt32(wParam) == 0);
break;
case WindowMessage.WM_TABLET_QUERYSYSTEMGESTURESTATUS:
handled = true;
NativeMethods.POINT pt1 = new NativeMethods.POINT(
NativeMethods.SignedLOWORD(lParam),
NativeMethods.SignedHIWORD(lParam));
SafeNativeMethods.ScreenToClient(new HandleRef(this, hwnd), pt1);
Point ptClient1 = new Point(pt1.x, pt1.y);
IInputElement inputElement = StylusDevice.LocalHitTest(_source.Value, ptClient1);
if (inputElement != null)
{
// walk up the parent chain
DependencyObject elementCur = (DependencyObject)inputElement;
bool isPressAndHoldEnabled = Stylus.GetIsPressAndHoldEnabled(elementCur);
bool isFlicksEnabled = Stylus.GetIsFlicksEnabled(elementCur);
bool isTapFeedbackEnabled = Stylus.GetIsTapFeedbackEnabled(elementCur);
bool isTouchFeedbackEnabled = Stylus.GetIsTouchFeedbackEnabled(elementCur);
uint flags = 0;
if (!isPressAndHoldEnabled)
{
flags |= TABLET_PRESSANDHOLD_DISABLED;
}
if (!isTapFeedbackEnabled)
{
flags |= TABLET_TAPFEEDBACK_DISABLED;
}
if (isTouchFeedbackEnabled)
{
flags |= TABLET_TOUCHUI_FORCEON;
}
else
{
flags |= TABLET_TOUCHUI_FORCEOFF;
}
if (!isFlicksEnabled)
{
flags |= TABLET_FLICKS_DISABLED;
}
result = new IntPtr(flags);
}
break;
case WindowMessage.WM_TABLET_FLICK:
handled = true;
int flickData = NativeMethods.IntPtrToInt32(wParam);
// We always handle any scroll actions if we are enabled. We do this when we see the SystemGesture Flick come through.
// Note: Scrolling happens on window flicked on even if it is not the active window.
if(_stylusLogic != null && _stylusLogic.Value.Enabled && (WispLogic.GetFlickAction(flickData) == StylusLogic.FlickAction.Scroll))
{
result = new IntPtr(0x0001); // tell UIHub the flick has already been handled.
}
break;
}
if (handled && EventTrace.IsEnabled(EventTrace.Keyword.KeywordInput | EventTrace.Keyword.KeywordPerf, EventTrace.Level.Info))
{
EventTrace.EventProvider.TraceEvent(EventTrace.Event.WClientInputMessage, EventTrace.Keyword.KeywordInput | EventTrace.Keyword.KeywordPerf, EventTrace.Level.Info,
(_source.Value.CompositionTarget != null ? _source.Value.CompositionTarget.Dispatcher.GetHashCode() : 0),
hwnd.ToInt64(),
msg,
(int)wParam,
(int)lParam);
}
return result;
}
/////////////////////////////////////////////////////////////////////
private SecurityCriticalDataClass<WispLogic> _stylusLogic;
/// <SecurityNote>
/// Critical: This is the HwndSurce object , not ok to expose
/// </SecurityNote>
private SecurityCriticalDataClass<HwndSource> _source;
/// <SecurityNote>
/// This data is critical and should never be exposed
/// </SecurityNote>
private SecurityCriticalDataClass<InputProviderSite> _site;
}
}
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