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

   1 //
   2 // System.Threading.SynchronizationContext.cs
   3 //
   4 // Author:
   5 //   Lluis Sanchez (lluis@novell.com)
   6 //
   7 // Copyright (C) 2004-2005 Novell, Inc (http://www.novell.com)
   8 //
   9 // Permission is hereby granted, free of charge, to any person obtaining
  10 // a copy of this software and associated documentation files (the
  11 // "Software"), to deal in the Software without restriction, including
  12 // without limitation the rights to use, copy, modify, merge, publish,
  13 // distribute, sublicense, and/or sell copies of the Software, and to
  14 // permit persons to whom the Software is furnished to do so, subject to
  15 // the following conditions:
  16 //
  17 // The above copyright notice and this permission notice shall be
  18 // included in all copies or substantial portions of the Software.
  19 //
  20 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  21 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  22 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  23 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  24 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  25 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  26 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  27 //
  28
  29 using System.Runtime.ConstrainedExecution;
  30 using System.Runtime.InteropServices;
  31
  32 namespace System.Threading
  33 {
  34         public class SynchronizationContext
  35         {
  36                 bool notification_required;
  37
  38                 [ThreadStatic]
  39                 static SynchronizationContext currentContext;
  40
  41                 public SynchronizationContext ()
  42                 {
  43                 }
  44
  45                 internal SynchronizationContext (SynchronizationContext context)
  46                 {
  47                         currentContext = context;
  48                 }
  49
  50                 public static SynchronizationContext Current {
  51                         get {
  52 #if MONODROID
  53                                 if (currentContext == null)
  54                                         currentContext = AndroidPlatform.GetDefaultSyncContext ();
  55 #endif
  56                                 return currentContext;
  57                         }
  58                 }
  59
  60                 // extracted from ../../../../external/referencesource/mscorlib/system/threading/synchronizationcontext.cs
  61                 // Get the last SynchronizationContext that was set explicitly (not flowed via ExecutionContext.Capture/Run)
  62                 internal static SynchronizationContext CurrentNoFlow
  63                 {
  64                         get
  65                         {
  66                                 // FIXME get context not flowed
  67                                 return Current;
  68                         }
  69                 }
  70
  71                 public virtual SynchronizationContext CreateCopy ()
  72                 {
  73                         return new SynchronizationContext (this);
  74                 }
  75
  76                 public bool IsWaitNotificationRequired ()
  77                 {
  78                         return notification_required;
  79                 }
  80
  81                 public virtual void OperationCompleted ()
  82                 {
  83                 }
  84
  85                 public virtual void OperationStarted ()
  86                 {
  87                 }
  88
  89                 public virtual void Post (SendOrPostCallback d, object state)
  90                 {
  91                         ThreadPool.QueueUserWorkItem (new WaitCallback (d), state);
  92                 }
  93
  94                 public virtual void Send (SendOrPostCallback d, object state)
  95                 {
  96                         d (state);
  97                 }
  98
  99                 public static void SetSynchronizationContext (SynchronizationContext syncContext)
 100                 {
 101                         currentContext = syncContext;
 102                 }
 103
 104 #if NET_2_1
 105                 [Obsolete]
 106                 public static void SetThreadStaticContext (SynchronizationContext syncContext)
 107                 {
 108                         currentContext = syncContext;
 109                 }
 110 #endif
 111
 112                 protected void SetWaitNotificationRequired ()
 113                 {
 114                         notification_required = true;
 115                 }
 116
 117                 [CLSCompliant (false)]
 118                 [PrePrepareMethod ()]
 119                 public virtual int Wait (IntPtr[] waitHandles, bool waitAll, int millisecondsTimeout)
 120                 {
 121                         return WaitHelper (waitHandles, waitAll, millisecondsTimeout);
 122                 }
 123
 124                 [MonoTODO]
 125                 [CLSCompliant (false)]
 126                 [ReliabilityContract (Consistency.WillNotCorruptState, Cer.MayFail)]
 127                 [PrePrepareMethod ()]
 128                 protected static int WaitHelper (IntPtr[] waitHandles, bool waitAll, int millisecondsTimeout)
 129                 {
 130                         throw new NotImplementedException ();
 131                 }
 132         }
 133 }