Merge pull request #93 from konrad-kruczynski/dispatcher_timer_fix

[mono.git] / mcs / class / corlib / System.Threading / CancellationToken.cs

diff --git a/mcs/class/corlib/System.Threading/CancellationToken.cs b/mcs/class/corlib/System.Threading/CancellationToken.cs
index 858b26840d8a146c69e75303df91df5a5d0ff75c..87dabbeea292fc8c7b8f2274915bed13486851cd 100644 (file)
--- a/mcs/class/corlib/System.Threading/CancellationToken.cs
+++ b/mcs/class/corlib/System.Threading/CancellationToken.cs
@@ -26,17 +26,24 @@
 
 using System;
 using System.Threading;
-using System.Collections.Generic;
 
-#if NET_4_0 || BOOTSTRAP_NET_4_0
+#if NET_4_0 || MOBILE
 namespace System.Threading
 {
+       [System.Diagnostics.DebuggerDisplay ("IsCancellationRequested = {IsCancellationRequested}")]
        public struct CancellationToken
        {
+               bool canBeCanceled;
+               bool initialized;
+               CancellationTokenSource source;
+
                public CancellationToken (bool canceled)
+                       : this ()
                {
-                       // dummy, this is actually set by CancellationTokenSource when the token is created
-                       Source = null;
+                       initialized = true;
+                       canBeCanceled = canceled;
+                       // This is correctly set later if token originates from a Source
+                       source = canceled ? CancellationTokenSource.CanceledSource : CancellationTokenSource.NoneSource;
                }
 
                public static CancellationToken None {
@@ -73,7 +80,8 @@ namespace System.Threading
 
                public void ThrowIfCancellationRequested ()
                {
-                       Source.ThrowIfCancellationRequested ();
+                       if (initialized && Source.IsCancellationRequested)
+                               throw new OperationCanceledException (this);
                }
 
                public bool Equals (CancellationToken other)
@@ -81,9 +89,9 @@ namespace System.Threading
                        return this.Source == other.Source;
                }
 
-               public override bool Equals (object obj)
+               public override bool Equals (object other)
                {
-                       return (obj is CancellationToken) ? Equals ((CancellationToken)obj) : false;
+                       return (other is CancellationToken) ? Equals ((CancellationToken)other) : false;
                }
 
                public override int GetHashCode ()
@@ -91,25 +99,25 @@ namespace System.Threading
                        return Source.GetHashCode ();
                }
 
-               public static bool operator == (CancellationToken lhs, CancellationToken rhs)
+               public static bool operator == (CancellationToken left, CancellationToken right)
                {
-                       return lhs.Equals (rhs);
+                       return left.Equals (right);
                }
 
-               public static bool operator != (CancellationToken lhs, CancellationToken rhs)
+               public static bool operator != (CancellationToken left, CancellationToken right)
                {
-                       return !lhs.Equals (rhs);
+                       return !left.Equals (right);
                }
 
                public bool CanBeCanceled {
                        get {
-                               return true;
+                               return canBeCanceled;
                        }
                }
 
                public bool IsCancellationRequested {
                        get {
-                               return Source.IsCancellationRequested;
+                               return initialized && Source.IsCancellationRequested;
                        }
                }
 
@@ -120,8 +128,20 @@ namespace System.Threading
                }
 
                internal CancellationTokenSource Source {
-                       get;
-                       set;
+                       get {
+                               if (!initialized)
+                                       CorrectlyInitialize ();
+                               return source;
+                       }
+                       set {
+                               source = value;
+                       }
+               }
+
+               void CorrectlyInitialize ()
+               {
+                       Source = CancellationTokenSource.NoneSource;
+                       initialized = true;
                }
        }
 }