[corlib] Implement ExecutionContext flow for async infrastructure. Fixes #24757
[mono.git] / 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 //
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10 // a copy of this software and associated documentation files (the
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16 // 
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18 // included in all copies or substantial portions of the Software.
19 // 
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24 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
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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                 public virtual SynchronizationContext CreateCopy ()
61                 {
62                         return new SynchronizationContext (this);
63                 }
64
65                 public bool IsWaitNotificationRequired ()
66                 {
67                         return notification_required;
68                 }
69
70                 public virtual void OperationCompleted ()
71                 {
72                 }
73
74                 public virtual void OperationStarted ()
75                 {
76                 }
77                 
78                 public virtual void Post (SendOrPostCallback d, object state)
79                 {
80                         ThreadPool.QueueUserWorkItem (new WaitCallback (d), state);
81                 }
82                 
83                 public virtual void Send (SendOrPostCallback d, object state)
84                 {
85                         d (state);
86                 }
87                 
88                 public static void SetSynchronizationContext (SynchronizationContext syncContext)
89                 {
90                         currentContext = syncContext;
91                 }
92
93 #if NET_2_1
94                 [Obsolete]
95                 public static void SetThreadStaticContext (SynchronizationContext syncContext)
96                 {
97                         currentContext = syncContext;
98                 }
99 #endif
100
101                 protected void SetWaitNotificationRequired ()
102                 {
103                         notification_required = true;
104                 }
105
106                 [CLSCompliant (false)]
107                 [PrePrepareMethod ()]
108                 public virtual int Wait (IntPtr[] waitHandles, bool waitAll, int millisecondsTimeout)
109                 {
110                         return WaitHelper (waitHandles, waitAll, millisecondsTimeout);
111                 }
112
113                 [MonoTODO]
114                 [CLSCompliant (false)]
115                 [ReliabilityContract (Consistency.WillNotCorruptState, Cer.MayFail)]
116                 [PrePrepareMethod ()]
117                 protected static int WaitHelper (IntPtr[] waitHandles, bool waitAll, int millisecondsTimeout)
118                 {
119                         throw new NotImplementedException ();
120                 }
121         }
122 }