class/corlib/System.Threading/ManualResetEventSlim.cs

   1 #if NET_4_0
   2 // ManuelResetEventSlim.cs
   3 //
   4 // Copyright (c) 2008 Jérémie "Garuma" Laval
   5 //
   6 // Permission is hereby granted, free of charge, to any person obtaining a copy
   7 // of this software and associated documentation files (the "Software"), to deal
   8 // in the Software without restriction, including without limitation the rights
   9 // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10 // copies of the Software, and to permit persons to whom the Software is
  11 // furnished to do so, subject to the following conditions:
  12 //
  13 // The above copyright notice and this permission notice shall be included in
  14 // all copies or substantial portions of the Software.
  15 //
  16 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  19 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22 // THE SOFTWARE.
  23 //
  24 //
  25
  26 using System;
  27 using System.Diagnostics;
  28
  29 namespace System.Threading
  30 {
  31         public class ManualResetEventSlim : IDisposable
  32         {
  33                 const int isSet    = 1;
  34                 const int isNotSet = 0;
  35                 const int defaultSpinCount = 20;
  36
  37                 int state;
  38                 readonly int spinCount;
  39
  40                 ManualResetEvent handle;
  41
  42                 public ManualResetEventSlim () : this(false, defaultSpinCount)
  43                 {
  44                 }
  45
  46                 public ManualResetEventSlim (bool initState) : this (initState, defaultSpinCount)
  47                 {
  48                 }
  49
  50                 public ManualResetEventSlim (bool initState, int spinCount)
  51                 {
  52                         if (spinCount < 0)
  53                                 throw new ArgumentOutOfRangeException ("spinCount is less than 0", "spinCount");
  54
  55                         this.state = initState ? isSet : isNotSet;
  56                         this.spinCount = spinCount;
  57                         this.handle = new ManualResetEvent (initState);
  58                 }
  59
  60                 public bool IsSet {
  61                         get {
  62                                 return state == isSet;
  63                         }
  64                 }
  65
  66                 public int SpinCount {
  67                         get {
  68                                 return spinCount;
  69                         }
  70                 }
  71
  72                 public void Reset ()
  73                 {
  74                         Interlocked.Exchange (ref state, isNotSet);
  75                 }
  76
  77                 public void Set ()
  78                 {
  79                         Interlocked.Exchange (ref state, isSet);
  80                 }
  81
  82                 public void Wait ()
  83                 {
  84                         Wait (CancellationToken.None);
  85                 }
  86
  87                 public bool Wait (int millisecondsTimeout)
  88                 {
  89                         return Wait (millisecondsTimeout, CancellationToken.None);
  90                 }
  91
  92                 public bool Wait (TimeSpan ts)
  93                 {
  94                         return Wait ((int)ts.TotalMilliseconds, CancellationToken.None);
  95                 }
  96
  97                 public void Wait (CancellationToken token)
  98                 {
  99                         Wait (-1, token);
 100                 }
 101
 102                 public bool Wait (int millisecondsTimeout, CancellationToken token)
 103                 {
 104                         if (millisecondsTimeout < -1)
 105                                 throw new ArgumentOutOfRangeException ("millisecondsTimeout",
 106                                                                        "millisecondsTimeout is a negative number other than -1");
 107
 108                         Watch s = Watch.StartNew ();
 109                         SpinWait sw = new SpinWait ();
 110                         int count = 0;
 111
 112                         while (state == isNotSet) {
 113                                 if (token.IsCancellationRequested)
 114                                         return false;
 115
 116                                 if (millisecondsTimeout > -1 && s.ElapsedMilliseconds > millisecondsTimeout)
 117                                         return false;
 118
 119                                 if (count < spinCount) {
 120                                     sw.SpinOnce ();
 121                                         count++;
 122                                 } else {
 123                                         Thread.Sleep (0);
 124                                 }
 125                         }
 126
 127                         return true;
 128                 }
 129
 130                 public bool Wait (TimeSpan ts, CancellationToken token)
 131                 {
 132                         return Wait ((int)ts.TotalMilliseconds, token);
 133                 }
 134
 135                 public WaitHandle WaitHandle {
 136                         get {
 137                                 return handle;
 138                         }
 139                 }
 140
 141                 #region IDisposable implementation
 142                 public void Dispose ()
 143                 {
 144                         Dispose(true);
 145                 }
 146
 147                 protected virtual void Dispose(bool managedRes)
 148                 {
 149
 150                 }
 151                 #endregion
 152
 153         }
 154 }
 155 #endif