mcs/class/corlib/System.Threading/CancellationToken.cs

   1 //
   2 // CancellationToken.cs
   3 //
   4 // Author:
   5 //       Jérémie "Garuma" Laval <jeremie.laval@gmail.com>
   6 //
   7 // Copyright (c) 2009 Jérémie "Garuma" Laval
   8 //
   9 // Permission is hereby granted, free of charge, to any person obtaining a copy
  10 // of this software and associated documentation files (the "Software"), to deal
  11 // in the Software without restriction, including without limitation the rights
  12 // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  13 // copies of the Software, and to permit persons to whom the Software is
  14 // furnished to do so, subject to the following conditions:
  15 //
  16 // The above copyright notice and this permission notice shall be included in
  17 // all copies or substantial portions of the Software.
  18 //
  19 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  20 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  21 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  22 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  23 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  24 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  25 // THE SOFTWARE.
  26
  27 using System;
  28 using System.Threading;
  29
  30 #if NET_4_0 || MOBILE
  31 namespace System.Threading
  32 {
  33         [System.Diagnostics.DebuggerDisplay ("IsCancellationRequested = {IsCancellationRequested}")]
  34         public struct CancellationToken
  35         {
  36                 public CancellationToken (bool canceled)
  37                         : this ()
  38                 {
  39                         // dummy, this is actually set by CancellationTokenSource when the token is created
  40                         Source = null;
  41                 }
  42
  43                 public static CancellationToken None {
  44                         get {
  45                                 return CancellationTokenSource.NoneSource.Token;
  46                         }
  47                 }
  48
  49                 public CancellationTokenRegistration Register (Action callback)
  50                 {
  51                         return Register (callback, false);
  52                 }
  53
  54                 public CancellationTokenRegistration Register (Action callback, bool useSynchronizationContext)
  55                 {
  56                         if (callback == null)
  57                                 throw new ArgumentNullException ("callback");
  58
  59                         return Source.Register (callback, useSynchronizationContext);
  60                 }
  61
  62                 public CancellationTokenRegistration Register (Action<object> callback, object state)
  63                 {
  64                         return Register (callback, state, false);
  65                 }
  66
  67                 public CancellationTokenRegistration Register (Action<object> callback, object state, bool useSynchronizationContext)
  68                 {
  69                         if (callback == null)
  70                                 throw new ArgumentNullException ("callback");
  71
  72                         return Register (() => callback (state), useSynchronizationContext);
  73                 }
  74
  75                 public void ThrowIfCancellationRequested ()
  76                 {
  77                         if (Source.IsCancellationRequested)
  78                                 throw new OperationCanceledException (this);
  79                 }
  80
  81                 public bool Equals (CancellationToken other)
  82                 {
  83                         return this.Source == other.Source;
  84                 }
  85
  86                 public override bool Equals (object other)
  87                 {
  88                         return (other is CancellationToken) ? Equals ((CancellationToken)other) : false;
  89                 }
  90
  91                 public override int GetHashCode ()
  92                 {
  93                         return Source.GetHashCode ();
  94                 }
  95
  96                 public static bool operator == (CancellationToken left, CancellationToken right)
  97                 {
  98                         return left.Equals (right);
  99                 }
 100
 101                 public static bool operator != (CancellationToken left, CancellationToken right)
 102                 {
 103                         return !left.Equals (right);
 104                 }
 105
 106                 public bool CanBeCanceled {
 107                         get {
 108                                 return true;
 109                         }
 110                 }
 111
 112                 public bool IsCancellationRequested {
 113                         get {
 114                                 return Source.IsCancellationRequested;
 115                         }
 116                 }
 117
 118                 public WaitHandle WaitHandle {
 119                         get {
 120                                 return Source.WaitHandle;
 121                         }
 122                 }
 123
 124                 internal CancellationTokenSource Source {
 125                         get;
 126                         set;
 127                 }
 128         }
 129 }
 130 #endif