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         [ComVisible (true)]
  43         public abstract class WaitHandle : MarshalByRefObject, IDisposable
  44         {
  45                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
  46                 private static extern bool WaitAll_internal(WaitHandle[] handles, int ms, bool exitContext);
  47
  48                 static void CheckArray (WaitHandle [] handles, bool waitAll)
  49                 {
  50                         if (handles == null)
  51                                 throw new ArgumentNullException ("waitHandles");
  52
  53                         int length = handles.Length;
  54                         if (length > 64)
  55                                 throw new NotSupportedException ("Too many handles");
  56
  57 #if false
  58                         //
  59                         // Although we should thrown an exception if this is an STA thread,
  60                         // Mono does not know anything about STA threads, and just makes
  61                         // things like Paint.NET not even possible to work.
  62                         //
  63                         // See bug #78455 for the bug this is supposed to fix.
  64                         //
  65                         if (waitAll && length > 1 && IsSTAThread)
  66                                 throw new NotSupportedException ("WaitAll for multiple handles is not allowed on an STA thread.");
  67 #endif
  68                         foreach (WaitHandle w in handles) {
  69                                 if (w == null)
  70                                         throw new ArgumentNullException ("waitHandles", "null handle");
  71
  72                                 if (w.safe_wait_handle == null)
  73                                         throw new ArgumentException ("null element found", "waitHandle");
  74
  75                         }
  76                 }
  77 #if false
  78                 // usage of property is commented - see above
  79                 static bool IsSTAThread {
  80                         get {
  81                                 bool isSTA = Thread.CurrentThread.ApartmentState ==
  82                                         ApartmentState.STA;
  83
  84                                 // FIXME: remove this check after Thread.ApartmentState
  85                                 // has been properly implemented.
  86                                 if (!isSTA) {
  87                                         Assembly asm = Assembly.GetEntryAssembly ();
  88                                         if (asm != null)
  89                                                 isSTA = asm.EntryPoint.GetCustomAttributes (typeof (STAThreadAttribute), false).Length > 0;
  90                                 }
  91
  92                                 return isSTA;
  93                         }
  94                 }
  95 #endif
  96                 public static bool WaitAll(WaitHandle[] waitHandles)
  97                 {
  98                         CheckArray (waitHandles, true);
  99                         return(WaitAll_internal(waitHandles, Timeout.Infinite, false));
 100                 }
 101
 102                 public static bool WaitAll(WaitHandle[] waitHandles, int millisecondsTimeout, bool exitContext)
 103                 {
 104                         CheckArray (waitHandles, true);
 105                         // check negative - except for -1 (which is Timeout.Infinite)
 106                         if (millisecondsTimeout < Timeout.Infinite)
 107                                 throw new ArgumentOutOfRangeException ("millisecondsTimeout");
 108
 109                         try {
 110                                 if (exitContext) SynchronizationAttribute.ExitContext ();
 111                                 return(WaitAll_internal(waitHandles, millisecondsTimeout, false));
 112                         }
 113                         finally {
 114                                 if (exitContext) SynchronizationAttribute.EnterContext ();
 115                         }
 116                 }
 117
 118                 public static bool WaitAll(WaitHandle[] waitHandles,
 119                                            TimeSpan timeout,
 120                                            bool exitContext)
 121                 {
 122                         CheckArray (waitHandles, true);
 123                         long ms = (long) timeout.TotalMilliseconds;
 124
 125                         if (ms < -1 || ms > Int32.MaxValue)
 126                                 throw new ArgumentOutOfRangeException ("timeout");
 127
 128                         try {
 129                                 if (exitContext) SynchronizationAttribute.ExitContext ();
 130                                 return (WaitAll_internal (waitHandles, (int) ms, exitContext));
 131                         }
 132                         finally {
 133                                 if (exitContext) SynchronizationAttribute.EnterContext ();
 134                         }
 135                 }
 136
 137                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 138                 private static extern int WaitAny_internal(WaitHandle[] handles, int ms, bool exitContext);
 139
 140                 // LAMESPEC: Doesn't specify how to signal failures
 141                 [ReliabilityContract (Consistency.WillNotCorruptState, Cer.MayFail)]
 142                 public static int WaitAny(WaitHandle[] waitHandles)
 143                 {
 144                         CheckArray (waitHandles, false);
 145                         return(WaitAny_internal(waitHandles, Timeout.Infinite, false));
 146                 }
 147
 148                 [ReliabilityContract (Consistency.WillNotCorruptState, Cer.MayFail)]
 149                 public static int WaitAny(WaitHandle[] waitHandles,
 150                                           int millisecondsTimeout,
 151                                           bool exitContext)
 152                 {
 153                         CheckArray (waitHandles, false);
 154                         // check negative - except for -1 (which is Timeout.Infinite)
 155                         if (millisecondsTimeout < Timeout.Infinite)
 156                                 throw new ArgumentOutOfRangeException ("millisecondsTimeout");
 157
 158                         try {
 159                                 if (exitContext) SynchronizationAttribute.ExitContext ();
 160                                 return(WaitAny_internal(waitHandles, millisecondsTimeout, exitContext));
 161                         }
 162                         finally {
 163                                 if (exitContext) SynchronizationAttribute.EnterContext ();
 164                         }
 165                 }
 166
 167                 [ReliabilityContract (Consistency.WillNotCorruptState, Cer.MayFail)]
 168                 public static int WaitAny(WaitHandle[] waitHandles, TimeSpan timeout)
 169                 {
 170                         return WaitAny (waitHandles, timeout, false);
 171                 }
 172
 173                 [ReliabilityContract (Consistency.WillNotCorruptState, Cer.MayFail)]
 174                 public static int WaitAny(WaitHandle[] waitHandles, int millisecondsTimeout)
 175                 {
 176                         return WaitAny (waitHandles, millisecondsTimeout, false);
 177                 }
 178
 179                 [ReliabilityContract (Consistency.WillNotCorruptState, Cer.MayFail)]
 180                 public static int WaitAny(WaitHandle[] waitHandles,
 181                                           TimeSpan timeout, bool exitContext)
 182                 {
 183                         CheckArray (waitHandles, false);
 184                         long ms = (long) timeout.TotalMilliseconds;
 185
 186                         if (ms < -1 || ms > Int32.MaxValue)
 187                                 throw new ArgumentOutOfRangeException ("timeout");
 188
 189                         try {
 190                                 if (exitContext) SynchronizationAttribute.ExitContext ();
 191                                 return (WaitAny_internal(waitHandles, (int) ms, exitContext));
 192                         }
 193                         finally {
 194                                 if (exitContext) SynchronizationAttribute.EnterContext ();
 195                         }
 196                 }
 197
 198                 protected WaitHandle()
 199                 {
 200                         // FIXME
 201                 }
 202
 203                 public virtual void Close() {
 204                         Dispose(true);
 205                         GC.SuppressFinalize (this);
 206                 }
 207
 208                 public const int WaitTimeout = 258;
 209
 210                 //
 211                 // In 2.0 we use SafeWaitHandles instead of IntPtrs
 212                 //
 213                 SafeWaitHandle safe_wait_handle;
 214
 215                 [Obsolete ("In the profiles > 2.x, use SafeHandle instead of Handle")]
 216                 public virtual IntPtr Handle {
 217                         get {
 218                                 return safe_wait_handle.DangerousGetHandle ();
 219                         }
 220
 221                         [SecurityPermission (SecurityAction.LinkDemand, UnmanagedCode = true)]
 222                         [SecurityPermission (SecurityAction.InheritanceDemand, UnmanagedCode = true)]
 223                         set {
 224                                 if (value == InvalidHandle)
 225                                         safe_wait_handle = new SafeWaitHandle (InvalidHandle, false);
 226                                 else
 227                                         safe_wait_handle = new SafeWaitHandle (value, true);
 228                         }
 229                 }
 230
 231                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 232                 private extern bool WaitOne_internal(IntPtr handle, int ms, bool exitContext);
 233
 234                 protected virtual void Dispose (bool explicitDisposing)
 235                 {
 236                         if (!disposed){
 237                                 disposed = true;
 238
 239                                 //
 240                                 // This is only the case if the handle was never properly initialized
 241                                 // most likely a bug in the derived class
 242                                 //
 243                                 if (safe_wait_handle == null)
 244                                         return;
 245
 246                                 lock (this){
 247                                         if (safe_wait_handle != null)
 248                                                 safe_wait_handle.Dispose ();
 249                                 }
 250                         }
 251                 }
 252
 253                 public SafeWaitHandle SafeWaitHandle {
 254                         [ReliabilityContract (Consistency.WillNotCorruptState, Cer.MayFail)]
 255                         get {
 256                                 return safe_wait_handle;
 257                         }
 258
 259                         [ReliabilityContract (Consistency.WillNotCorruptState, Cer.Success)]
 260                         set {
 261                                 if (value == null)
 262                                         safe_wait_handle = new SafeWaitHandle (InvalidHandle, false);
 263                                 else
 264                                         safe_wait_handle = value;
 265                         }
 266                 }
 267
 268                 public static bool SignalAndWait (WaitHandle toSignal,
 269                                                   WaitHandle toWaitOn)
 270                 {
 271                         return SignalAndWait (toSignal, toWaitOn, -1, false);
 272                 }
 273
 274                 public static bool SignalAndWait (WaitHandle toSignal,
 275                                                   WaitHandle toWaitOn,
 276                                                   int millisecondsTimeout,
 277                                                   bool exitContext)
 278                 {
 279                         if (toSignal == null)
 280                                 throw new ArgumentNullException ("toSignal");
 281                         if (toWaitOn == null)
 282                                 throw new ArgumentNullException ("toWaitOn");
 283
 284                         if (millisecondsTimeout < -1)
 285                                 throw new ArgumentOutOfRangeException ("millisecondsTimeout");
 286
 287                         return SignalAndWait_Internal (toSignal.Handle, toWaitOn.Handle, millisecondsTimeout, exitContext);
 288                 }
 289
 290                 public static bool SignalAndWait (WaitHandle toSignal,
 291                                                   WaitHandle toWaitOn,
 292                                                   TimeSpan timeout,
 293                                                   bool exitContext)
 294                 {
 295                         double ms = timeout.TotalMilliseconds;
 296                         if (ms > Int32.MaxValue)
 297                                 throw new ArgumentOutOfRangeException ("timeout");
 298
 299                         return SignalAndWait (toSignal, toWaitOn, Convert.ToInt32 (ms), false);
 300                 }
 301
 302                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 303                 static extern bool SignalAndWait_Internal (IntPtr toSignal, IntPtr toWaitOn, int ms, bool exitContext);
 304
 305                 public virtual bool WaitOne()
 306                 {
 307                         CheckDisposed ();
 308                         bool release = false;
 309                         try {
 310                                 safe_wait_handle.DangerousAddRef (ref release);
 311                                 return (WaitOne_internal(safe_wait_handle.DangerousGetHandle (), Timeout.Infinite, false));
 312                         } finally {
 313                                 if (release)
 314                                         safe_wait_handle.DangerousRelease ();
 315                         }
 316                 }
 317
 318                 public virtual bool WaitOne(int millisecondsTimeout, bool exitContext)
 319                 {
 320                         CheckDisposed ();
 321                         // check negative - except for -1 (which is Timeout.Infinite)
 322                         if (millisecondsTimeout < Timeout.Infinite)
 323                                 throw new ArgumentOutOfRangeException ("millisecondsTimeout");
 324
 325                         bool release = false;
 326                         try {
 327                                 if (exitContext)
 328                                         SynchronizationAttribute.ExitContext ();
 329                                 safe_wait_handle.DangerousAddRef (ref release);
 330                                 return (WaitOne_internal(safe_wait_handle.DangerousGetHandle (), millisecondsTimeout, exitContext));
 331                         } finally {
 332                                 if (exitContext)
 333                                         SynchronizationAttribute.EnterContext ();
 334                                 if (release)
 335                                         safe_wait_handle.DangerousRelease ();
 336                         }
 337                 }
 338
 339                 public virtual bool WaitOne (int millisecondsTimeout)
 340                 {
 341                         return WaitOne (millisecondsTimeout, false);
 342                 }
 343
 344                 public virtual bool WaitOne (TimeSpan timeout)
 345                 {
 346                         return WaitOne (timeout, false);
 347                 }
 348
 349                 public virtual bool WaitOne(TimeSpan timeout, bool exitContext)
 350                 {
 351                         CheckDisposed ();
 352                         long ms = (long) timeout.TotalMilliseconds;
 353                         if (ms < -1 || ms > Int32.MaxValue)
 354                                 throw new ArgumentOutOfRangeException ("timeout");
 355
 356                         bool release = false;
 357                         try {
 358                                 if (exitContext)
 359                                         SynchronizationAttribute.ExitContext ();
 360                                 safe_wait_handle.DangerousAddRef (ref release);
 361                                 return (WaitOne_internal(safe_wait_handle.DangerousGetHandle (), (int) ms, exitContext));
 362                         }
 363                         finally {
 364                                 if (exitContext)
 365                                         SynchronizationAttribute.EnterContext ();
 366                                 if (release)
 367                                         safe_wait_handle.DangerousRelease ();
 368                         }
 369                 }
 370
 371                 internal void CheckDisposed ()
 372                 {
 373                         if (disposed || safe_wait_handle == null)
 374                                 throw new ObjectDisposedException (GetType ().FullName);
 375                 }
 376
 377                 public static bool WaitAll(WaitHandle[] waitHandles, int millisecondsTimeout)
 378                 {
 379                         return WaitAll (waitHandles, millisecondsTimeout, false);
 380                 }
 381
 382                 public static bool WaitAll(WaitHandle[] waitHandles, TimeSpan timeout)
 383                 {
 384                         return WaitAll (waitHandles, timeout, false);
 385                 }
 386
 387                 protected static readonly IntPtr InvalidHandle = (IntPtr) (-1);
 388                 bool disposed = false;
 389
 390                 void IDisposable.Dispose() {
 391                         Dispose(true);
 392                         // Take yourself off the Finalization queue
 393                         GC.SuppressFinalize(this);
 394                 }
 395
 396                 ~WaitHandle() {
 397                         Dispose(false);
 398                 }
 399         }
 400 }