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         [StructLayout (LayoutKind.Sequential)]
  44         public abstract class WaitHandle
  45                 : MarshalByRefObject, IDisposable
  46         {
  47                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
  48                 private static extern bool WaitAll_internal(WaitHandle[] handles, int ms, bool exitContext);
  49
  50                 static void CheckArray (WaitHandle [] handles, bool waitAll)
  51                 {
  52                         if (handles == null)
  53                                 throw new ArgumentNullException ("waitHandles");
  54
  55                         int length = handles.Length;
  56                         if (length > 64)
  57                                 throw new NotSupportedException ("Too many handles");
  58
  59                         if (handles.Length == 0) {
  60                                 // MS throws different exceptions from the different methods.
  61                                 if (waitAll)
  62                                         throw new ArgumentNullException ("waitHandles");
  63                                 else
  64                                         throw new ArgumentException ();
  65                         }
  66
  67 #if false
  68                         //
  69                         // Although we should thrown an exception if this is an STA thread,
  70                         // Mono does not know anything about STA threads, and just makes
  71                         // things like Paint.NET not even possible to work.
  72                         //
  73                         // See bug #78455 for the bug this is supposed to fix.
  74                         //
  75                         if (waitAll && length > 1 && IsSTAThread)
  76                                 throw new NotSupportedException ("WaitAll for multiple handles is not allowed on an STA thread.");
  77 #endif
  78                         foreach (WaitHandle w in handles) {
  79                                 if (w == null)
  80                                         throw new ArgumentNullException ("waitHandles", "null handle");
  81
  82                                 if (w.safe_wait_handle == null)
  83                                         throw new ArgumentException ("null element found", "waitHandle");
  84
  85                         }
  86                 }
  87 #if false
  88                 // usage of property is commented - see above
  89                 static bool IsSTAThread {
  90                         get {
  91                                 bool isSTA = Thread.CurrentThread.ApartmentState ==
  92                                         ApartmentState.STA;
  93
  94                                 // FIXME: remove this check after Thread.ApartmentState
  95                                 // has been properly implemented.
  96                                 if (!isSTA) {
  97                                         Assembly asm = Assembly.GetEntryAssembly ();
  98                                         if (asm != null)
  99                                                 isSTA = asm.EntryPoint.GetCustomAttributes (typeof (STAThreadAttribute), false).Length > 0;
 100                                 }
 101
 102                                 return isSTA;
 103                         }
 104                 }
 105 #endif
 106                 public static bool WaitAll(WaitHandle[] waitHandles)
 107                 {
 108                         CheckArray (waitHandles, true);
 109                         return(WaitAll_internal(waitHandles, Timeout.Infinite, false));
 110                 }
 111
 112                 public static bool WaitAll(WaitHandle[] waitHandles, int millisecondsTimeout, bool exitContext)
 113                 {
 114                         CheckArray (waitHandles, true);
 115                         // check negative - except for -1 (which is Timeout.Infinite)
 116                         if (millisecondsTimeout < Timeout.Infinite)
 117                                 throw new ArgumentOutOfRangeException ("millisecondsTimeout");
 118
 119                         try {
 120                                 if (exitContext) {
 121 #if MONOTOUCH
 122                                         throw new NotSupportedException ("exitContext == true is not supported");
 123 #else
 124                                         SynchronizationAttribute.ExitContext ();
 125 #endif
 126                                 }
 127                                 return(WaitAll_internal(waitHandles, millisecondsTimeout, false));
 128                         }
 129                         finally {
 130                                 if (exitContext) SynchronizationAttribute.EnterContext ();
 131                         }
 132                 }
 133
 134                 public static bool WaitAll(WaitHandle[] waitHandles,
 135                                            TimeSpan timeout,
 136                                            bool exitContext)
 137                 {
 138                         CheckArray (waitHandles, true);
 139                         long ms = (long) timeout.TotalMilliseconds;
 140
 141                         if (ms < -1 || ms > Int32.MaxValue)
 142                                 throw new ArgumentOutOfRangeException ("timeout");
 143
 144                         try {
 145                                 if (exitContext) {
 146 #if MONOTOUCH
 147                                         throw new NotSupportedException ("exitContext == true is not supported");
 148 #else
 149                                         SynchronizationAttribute.ExitContext ();
 150 #endif
 151                                 }
 152                                 return (WaitAll_internal (waitHandles, (int) ms, exitContext));
 153                         }
 154                         finally {
 155                                 if (exitContext) SynchronizationAttribute.EnterContext ();
 156                         }
 157                 }
 158
 159                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 160                 private static extern int WaitAny_internal(WaitHandle[] handles, int ms, bool exitContext);
 161
 162                 // LAMESPEC: Doesn't specify how to signal failures
 163                 [ReliabilityContract (Consistency.WillNotCorruptState, Cer.MayFail)]
 164                 public static int WaitAny(WaitHandle[] waitHandles)
 165                 {
 166                         CheckArray (waitHandles, false);
 167                         return(WaitAny_internal(waitHandles, Timeout.Infinite, false));
 168                 }
 169
 170                 [ReliabilityContract (Consistency.WillNotCorruptState, Cer.MayFail)]
 171                 public static int WaitAny(WaitHandle[] waitHandles,
 172                                           int millisecondsTimeout,
 173                                           bool exitContext)
 174                 {
 175                         CheckArray (waitHandles, false);
 176                         // check negative - except for -1 (which is Timeout.Infinite)
 177                         if (millisecondsTimeout < Timeout.Infinite)
 178                                 throw new ArgumentOutOfRangeException ("millisecondsTimeout");
 179
 180                         try {
 181                                 if (exitContext) {
 182 #if MONOTOUCH
 183                                         throw new NotSupportedException ("exitContext == true is not supported");
 184 #else
 185                                         SynchronizationAttribute.ExitContext ();
 186 #endif
 187                                 }
 188                                 return(WaitAny_internal(waitHandles, millisecondsTimeout, exitContext));
 189                         }
 190                         finally {
 191                                 if (exitContext) SynchronizationAttribute.EnterContext ();
 192                         }
 193                 }
 194
 195                 [ReliabilityContract (Consistency.WillNotCorruptState, Cer.MayFail)]
 196                 public static int WaitAny(WaitHandle[] waitHandles, TimeSpan timeout)
 197                 {
 198                         return WaitAny (waitHandles, timeout, false);
 199                 }
 200
 201                 [ReliabilityContract (Consistency.WillNotCorruptState, Cer.MayFail)]
 202                 public static int WaitAny(WaitHandle[] waitHandles, int millisecondsTimeout)
 203                 {
 204                         return WaitAny (waitHandles, millisecondsTimeout, false);
 205                 }
 206
 207                 [ReliabilityContract (Consistency.WillNotCorruptState, Cer.MayFail)]
 208                 public static int WaitAny(WaitHandle[] waitHandles,
 209                                           TimeSpan timeout, bool exitContext)
 210                 {
 211                         CheckArray (waitHandles, false);
 212                         long ms = (long) timeout.TotalMilliseconds;
 213
 214                         if (ms < -1 || ms > Int32.MaxValue)
 215                                 throw new ArgumentOutOfRangeException ("timeout");
 216
 217                         try {
 218                                 if (exitContext) {
 219 #if MONOTOUCH
 220                                         throw new NotSupportedException ("exitContext == true is not supported");
 221 #else
 222                                         SynchronizationAttribute.ExitContext ();
 223 #endif
 224                                 }
 225                                 return (WaitAny_internal(waitHandles, (int) ms, exitContext));
 226                         }
 227                         finally {
 228                                 if (exitContext) SynchronizationAttribute.EnterContext ();
 229                         }
 230                 }
 231
 232                 protected WaitHandle()
 233                 {
 234                         // FIXME
 235                 }
 236
 237                 public virtual void Close ()
 238                 {
 239                         Dispose(true);
 240                 }
 241
 242                 public void Dispose ()
 243                 {
 244                         Close ();
 245                 }
 246
 247                 public const int WaitTimeout = 258;
 248
 249                 //
 250                 // In 2.0 we use SafeWaitHandles instead of IntPtrs
 251                 //
 252                 SafeWaitHandle safe_wait_handle;
 253
 254                 [Obsolete ("In the profiles > 2.x, use SafeHandle instead of Handle")]
 255                 public virtual IntPtr Handle {
 256                         get {
 257                                 return safe_wait_handle.DangerousGetHandle ();
 258                         }
 259
 260                         [SecurityPermission (SecurityAction.LinkDemand, UnmanagedCode = true)]
 261                         [SecurityPermission (SecurityAction.InheritanceDemand, UnmanagedCode = true)]
 262                         set {
 263                                 if (value == InvalidHandle)
 264                                         safe_wait_handle = new SafeWaitHandle (InvalidHandle, false);
 265                                 else
 266                                         safe_wait_handle = new SafeWaitHandle (value, true);
 267                         }
 268                 }
 269
 270                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 271                 private extern bool WaitOne_internal(IntPtr handle, int ms, bool exitContext);
 272
 273                 protected virtual void Dispose (bool explicitDisposing)
 274                 {
 275                         if (!disposed){
 276
 277                                 //
 278                                 // This is only the case if the handle was never properly initialized
 279                                 // most likely a bug in the derived class
 280                                 //
 281                                 if (safe_wait_handle == null)
 282                                         return;
 283
 284                                 lock (this){
 285                                         if (disposed)
 286                                                 return;
 287
 288                                         disposed = true;
 289                                         if (safe_wait_handle != null)
 290                                                 safe_wait_handle.Dispose ();
 291                                 }
 292                         }
 293                 }
 294
 295                 public SafeWaitHandle SafeWaitHandle {
 296                         [ReliabilityContract (Consistency.WillNotCorruptState, Cer.MayFail)]
 297                         get {
 298                                 return safe_wait_handle;
 299                         }
 300
 301                         [ReliabilityContract (Consistency.WillNotCorruptState, Cer.Success)]
 302                         set {
 303                                 if (value == null)
 304                                         safe_wait_handle = new SafeWaitHandle (InvalidHandle, false);
 305                                 else
 306                                         safe_wait_handle = value;
 307                         }
 308                 }
 309
 310                 public static bool SignalAndWait (WaitHandle toSignal,
 311                                                   WaitHandle toWaitOn)
 312                 {
 313                         return SignalAndWait (toSignal, toWaitOn, -1, false);
 314                 }
 315
 316                 public static bool SignalAndWait (WaitHandle toSignal,
 317                                                   WaitHandle toWaitOn,
 318                                                   int millisecondsTimeout,
 319                                                   bool exitContext)
 320                 {
 321                         if (toSignal == null)
 322                                 throw new ArgumentNullException ("toSignal");
 323                         if (toWaitOn == null)
 324                                 throw new ArgumentNullException ("toWaitOn");
 325
 326                         if (millisecondsTimeout < -1)
 327                                 throw new ArgumentOutOfRangeException ("millisecondsTimeout");
 328
 329                         return SignalAndWait_Internal (toSignal.Handle, toWaitOn.Handle, millisecondsTimeout, exitContext);
 330                 }
 331
 332                 public static bool SignalAndWait (WaitHandle toSignal,
 333                                                   WaitHandle toWaitOn,
 334                                                   TimeSpan timeout,
 335                                                   bool exitContext)
 336                 {
 337                         double ms = timeout.TotalMilliseconds;
 338                         if (ms > Int32.MaxValue)
 339                                 throw new ArgumentOutOfRangeException ("timeout");
 340
 341                         return SignalAndWait (toSignal, toWaitOn, Convert.ToInt32 (ms), false);
 342                 }
 343
 344                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 345                 static extern bool SignalAndWait_Internal (IntPtr toSignal, IntPtr toWaitOn, int ms, bool exitContext);
 346
 347                 public virtual bool WaitOne()
 348                 {
 349                         CheckDisposed ();
 350                         bool release = false;
 351                         try {
 352                                 safe_wait_handle.DangerousAddRef (ref release);
 353                                 return (WaitOne_internal(safe_wait_handle.DangerousGetHandle (), Timeout.Infinite, false));
 354                         } finally {
 355                                 if (release)
 356                                         safe_wait_handle.DangerousRelease ();
 357                         }
 358                 }
 359
 360                 public virtual bool WaitOne(int millisecondsTimeout, bool exitContext)
 361                 {
 362                         CheckDisposed ();
 363                         // check negative - except for -1 (which is Timeout.Infinite)
 364                         if (millisecondsTimeout < Timeout.Infinite)
 365                                 throw new ArgumentOutOfRangeException ("millisecondsTimeout");
 366
 367                         bool release = false;
 368                         try {
 369                                 if (exitContext) {
 370 #if !MONOTOUCH
 371                                         SynchronizationAttribute.ExitContext ();
 372 #endif
 373                                 }
 374                                 safe_wait_handle.DangerousAddRef (ref release);
 375                                 return (WaitOne_internal(safe_wait_handle.DangerousGetHandle (), millisecondsTimeout, exitContext));
 376                         } finally {
 377 #if !MONOTOUCH
 378                                 if (exitContext)
 379                                         SynchronizationAttribute.EnterContext ();
 380 #endif
 381                                 if (release)
 382                                         safe_wait_handle.DangerousRelease ();
 383                         }
 384                 }
 385
 386                 public virtual bool WaitOne (int millisecondsTimeout)
 387                 {
 388                         return WaitOne (millisecondsTimeout, false);
 389                 }
 390
 391                 public virtual bool WaitOne (TimeSpan timeout)
 392                 {
 393                         return WaitOne (timeout, false);
 394                 }
 395
 396                 public virtual bool WaitOne(TimeSpan timeout, bool exitContext)
 397                 {
 398                         CheckDisposed ();
 399                         long ms = (long) timeout.TotalMilliseconds;
 400                         if (ms < -1 || ms > Int32.MaxValue)
 401                                 throw new ArgumentOutOfRangeException ("timeout");
 402
 403                         bool release = false;
 404                         try {
 405                                 if (exitContext) {
 406 #if !MONOTOUCH
 407                                         SynchronizationAttribute.ExitContext ();
 408 #endif
 409                                 }
 410                                 safe_wait_handle.DangerousAddRef (ref release);
 411                                 return (WaitOne_internal(safe_wait_handle.DangerousGetHandle (), (int) ms, exitContext));
 412                         }
 413                         finally {
 414 #if !MONOTOUCH
 415                                 if (exitContext)
 416                                         SynchronizationAttribute.EnterContext ();
 417 #endif
 418                                 if (release)
 419                                         safe_wait_handle.DangerousRelease ();
 420                         }
 421                 }
 422
 423                 internal void CheckDisposed ()
 424                 {
 425                         if (disposed || safe_wait_handle == null)
 426                                 throw new ObjectDisposedException (GetType ().FullName);
 427                 }
 428
 429                 public static bool WaitAll(WaitHandle[] waitHandles, int millisecondsTimeout)
 430                 {
 431                         return WaitAll (waitHandles, millisecondsTimeout, false);
 432                 }
 433
 434                 public static bool WaitAll(WaitHandle[] waitHandles, TimeSpan timeout)
 435                 {
 436                         return WaitAll (waitHandles, timeout, false);
 437                 }
 438
 439                 protected static readonly IntPtr InvalidHandle = (IntPtr) (-1);
 440                 bool disposed = false;
 441         }
 442 }