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

   1 //
   2 // System.Threading.WaitHandle.cs
   3 //
   4 // Author:
   5 //      Dick Porter (dick@ximian.com)
   6 //      Gonzalo Paniagua Javier (gonzalo@ximian.com
   7 //
   8 // (C) 2002,2003 Ximian, Inc.   (http://www.ximian.com)
   9 // Copyright (C) 2004-2005 Novell, Inc (http://www.novell.com)
  10 //
  11 // Permission is hereby granted, free of charge, to any person obtaining
  12 // a copy of this software and associated documentation files (the
  13 // "Software"), to deal in the Software without restriction, including
  14 // without limitation the rights to use, copy, modify, merge, publish,
  15 // distribute, sublicense, and/or sell copies of the Software, and to
  16 // permit persons to whom the Software is furnished to do so, subject to
  17 // the following conditions:
  18 //
  19 // The above copyright notice and this permission notice shall be
  20 // included in all copies or substantial portions of the Software.
  21 //
  22 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  23 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  24 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  25 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  26 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  27 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  28 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  29 //
  30
  31 using System;
  32 using System.Reflection;
  33 using System.Runtime.CompilerServices;
  34 using System.Runtime.Remoting.Contexts;
  35 using System.Security.Permissions;
  36 using System.Runtime.InteropServices;
  37 using Microsoft.Win32.SafeHandles;
  38 using System.Runtime.ConstrainedExecution;
  39
  40 namespace System.Threading
  41 {
  42         [StructLayout (LayoutKind.Sequential)]
  43         public abstract partial class WaitHandle
  44                 : MarshalByRefObject, IDisposable
  45         {
  46                 protected static readonly IntPtr InvalidHandle = (IntPtr) (-1);
  47
  48                 internal const int MaxWaitHandles = 64;
  49
  50                 static int WaitMultiple(WaitHandle[] waitHandles, int millisecondsTimeout, bool exitContext, bool WaitAll)
  51                 {
  52                         if (waitHandles.Length > MaxWaitHandles)
  53                                 return WAIT_FAILED;
  54
  55                         int release_last = -1;
  56
  57                         try {
  58 #if !DISABLE_REMOTING
  59                                 if (exitContext)
  60                                         SynchronizationAttribute.ExitContext ();
  61 #endif
  62
  63                                 for (int i = 0; i < waitHandles.Length; ++i) {
  64                                         try {} finally {
  65                                                 /* we have to put it in a finally block, to avoid having a ThreadAbortException
  66                                                  * between the return from DangerousAddRef and the assignement to release_last */
  67                                                 bool release = false;
  68                                                 waitHandles [i].SafeWaitHandle.DangerousAddRef (ref release);
  69                                                 release_last = i;
  70                                         }
  71                                 }
  72
  73                                 unsafe {
  74                                         IntPtr* handles = stackalloc IntPtr[waitHandles.Length];
  75
  76                                         for (int i = 0; i < waitHandles.Length; ++i)
  77                                                 handles[i] = waitHandles[i].SafeWaitHandle.DangerousGetHandle ();
  78
  79                                         return Wait_internal(handles, waitHandles.Length, WaitAll, millisecondsTimeout);
  80                                 }
  81                         } finally {
  82                                 for (int i = release_last; i >= 0; --i) {
  83                                         waitHandles [i].SafeWaitHandle.DangerousRelease ();
  84                                 }
  85
  86 #if !DISABLE_REMOTING
  87                                 if (exitContext)
  88                                         SynchronizationAttribute.EnterContext ();
  89 #endif
  90                         }
  91                 }
  92
  93                 static int WaitOneNative (SafeHandle waitableSafeHandle, uint millisecondsTimeout, bool hasThreadAffinity, bool exitContext)
  94                 {
  95                         bool release = false;
  96                         try {
  97 #if !DISABLE_REMOTING
  98                                 if (exitContext)
  99                                         SynchronizationAttribute.ExitContext ();
 100 #endif
 101
 102                                 waitableSafeHandle.DangerousAddRef (ref release);
 103
 104                                 unsafe {
 105                                         IntPtr handle = waitableSafeHandle.DangerousGetHandle();
 106                                         return Wait_internal(&handle, 1, false, (int)millisecondsTimeout);
 107                                 }
 108                         } finally {
 109                                 if (release)
 110                                         waitableSafeHandle.DangerousRelease ();
 111
 112 #if !DISABLE_REMOTING
 113                                 if (exitContext)
 114                                         SynchronizationAttribute.EnterContext ();
 115 #endif
 116                         }
 117                 }
 118
 119                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 120                 unsafe static extern int Wait_internal(IntPtr* handles, int numHandles, bool waitAll, int ms);
 121
 122                 static int SignalAndWaitOne (SafeWaitHandle waitHandleToSignal,SafeWaitHandle waitHandleToWaitOn, int millisecondsTimeout, bool hasThreadAffinity,  bool exitContext)
 123                 {
 124                         bool releaseHandleToSignal = false, releaseHandleToWaitOn = false;
 125                         try {
 126                                 waitHandleToSignal.DangerousAddRef (ref releaseHandleToSignal);
 127                                 waitHandleToWaitOn.DangerousAddRef (ref releaseHandleToWaitOn);
 128
 129                                 return SignalAndWait_Internal (waitHandleToSignal.DangerousGetHandle (), waitHandleToWaitOn.DangerousGetHandle (), millisecondsTimeout);
 130                         } finally {
 131                                 if (releaseHandleToSignal)
 132                                         waitHandleToSignal.DangerousRelease ();
 133                                 if (releaseHandleToWaitOn)
 134                                         waitHandleToWaitOn.DangerousRelease ();
 135                         }
 136                 }
 137
 138                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 139                 static extern int SignalAndWait_Internal (IntPtr toSignal, IntPtr toWaitOn, int ms);
 140         }
 141 }