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 #if NET_4_0
 243                 public void Dispose ()
 244 #else
 245                 void IDisposable.Dispose ()
 246 #endif
 247                 {
 248                         Close ();
 249                 }
 250
 251                 public const int WaitTimeout = 258;
 252
 253                 //
 254                 // In 2.0 we use SafeWaitHandles instead of IntPtrs
 255                 //
 256                 SafeWaitHandle safe_wait_handle;
 257
 258                 [Obsolete ("In the profiles > 2.x, use SafeHandle instead of Handle")]
 259                 public virtual IntPtr Handle {
 260                         get {
 261                                 return safe_wait_handle.DangerousGetHandle ();
 262                         }
 263
 264                         [SecurityPermission (SecurityAction.LinkDemand, UnmanagedCode = true)]
 265                         [SecurityPermission (SecurityAction.InheritanceDemand, UnmanagedCode = true)]
 266                         set {
 267                                 if (value == InvalidHandle)
 268                                         safe_wait_handle = new SafeWaitHandle (InvalidHandle, false);
 269                                 else
 270                                         safe_wait_handle = new SafeWaitHandle (value, true);
 271                         }
 272                 }
 273
 274                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 275                 private extern bool WaitOne_internal(IntPtr handle, int ms, bool exitContext);
 276
 277                 protected virtual void Dispose (bool explicitDisposing)
 278                 {
 279                         if (!disposed){
 280
 281                                 //
 282                                 // This is only the case if the handle was never properly initialized
 283                                 // most likely a bug in the derived class
 284                                 //
 285                                 if (safe_wait_handle == null)
 286                                         return;
 287
 288                                 lock (this){
 289                                         if (disposed)
 290                                                 return;
 291
 292                                         disposed = true;
 293                                         if (safe_wait_handle != null)
 294                                                 safe_wait_handle.Dispose ();
 295                                 }
 296                         }
 297                 }
 298
 299                 public SafeWaitHandle SafeWaitHandle {
 300                         [ReliabilityContract (Consistency.WillNotCorruptState, Cer.MayFail)]
 301                         get {
 302                                 return safe_wait_handle;
 303                         }
 304
 305                         [ReliabilityContract (Consistency.WillNotCorruptState, Cer.Success)]
 306                         set {
 307                                 if (value == null)
 308                                         safe_wait_handle = new SafeWaitHandle (InvalidHandle, false);
 309                                 else
 310                                         safe_wait_handle = value;
 311                         }
 312                 }
 313
 314                 public static bool SignalAndWait (WaitHandle toSignal,
 315                                                   WaitHandle toWaitOn)
 316                 {
 317                         return SignalAndWait (toSignal, toWaitOn, -1, false);
 318                 }
 319
 320                 public static bool SignalAndWait (WaitHandle toSignal,
 321                                                   WaitHandle toWaitOn,
 322                                                   int millisecondsTimeout,
 323                                                   bool exitContext)
 324                 {
 325                         if (toSignal == null)
 326                                 throw new ArgumentNullException ("toSignal");
 327                         if (toWaitOn == null)
 328                                 throw new ArgumentNullException ("toWaitOn");
 329
 330                         if (millisecondsTimeout < -1)
 331                                 throw new ArgumentOutOfRangeException ("millisecondsTimeout");
 332
 333                         return SignalAndWait_Internal (toSignal.Handle, toWaitOn.Handle, millisecondsTimeout, exitContext);
 334                 }
 335
 336                 public static bool SignalAndWait (WaitHandle toSignal,
 337                                                   WaitHandle toWaitOn,
 338                                                   TimeSpan timeout,
 339                                                   bool exitContext)
 340                 {
 341                         double ms = timeout.TotalMilliseconds;
 342                         if (ms > Int32.MaxValue)
 343                                 throw new ArgumentOutOfRangeException ("timeout");
 344
 345                         return SignalAndWait (toSignal, toWaitOn, Convert.ToInt32 (ms), false);
 346                 }
 347
 348                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 349                 static extern bool SignalAndWait_Internal (IntPtr toSignal, IntPtr toWaitOn, int ms, bool exitContext);
 350
 351                 public virtual bool WaitOne()
 352                 {
 353                         CheckDisposed ();
 354                         bool release = false;
 355                         try {
 356                                 safe_wait_handle.DangerousAddRef (ref release);
 357                                 return (WaitOne_internal(safe_wait_handle.DangerousGetHandle (), Timeout.Infinite, false));
 358                         } finally {
 359                                 if (release)
 360                                         safe_wait_handle.DangerousRelease ();
 361                         }
 362                 }
 363
 364                 public virtual bool WaitOne(int millisecondsTimeout, bool exitContext)
 365                 {
 366                         CheckDisposed ();
 367                         // check negative - except for -1 (which is Timeout.Infinite)
 368                         if (millisecondsTimeout < Timeout.Infinite)
 369                                 throw new ArgumentOutOfRangeException ("millisecondsTimeout");
 370
 371                         bool release = false;
 372                         try {
 373                                 if (exitContext) {
 374 #if !MONOTOUCH
 375                                         SynchronizationAttribute.ExitContext ();
 376 #endif
 377                                 }
 378                                 safe_wait_handle.DangerousAddRef (ref release);
 379                                 return (WaitOne_internal(safe_wait_handle.DangerousGetHandle (), millisecondsTimeout, exitContext));
 380                         } finally {
 381 #if !MONOTOUCH
 382                                 if (exitContext)
 383                                         SynchronizationAttribute.EnterContext ();
 384 #endif
 385                                 if (release)
 386                                         safe_wait_handle.DangerousRelease ();
 387                         }
 388                 }
 389
 390                 public virtual bool WaitOne (int millisecondsTimeout)
 391                 {
 392                         return WaitOne (millisecondsTimeout, false);
 393                 }
 394
 395                 public virtual bool WaitOne (TimeSpan timeout)
 396                 {
 397                         return WaitOne (timeout, false);
 398                 }
 399
 400                 public virtual bool WaitOne(TimeSpan timeout, bool exitContext)
 401                 {
 402                         CheckDisposed ();
 403                         long ms = (long) timeout.TotalMilliseconds;
 404                         if (ms < -1 || ms > Int32.MaxValue)
 405                                 throw new ArgumentOutOfRangeException ("timeout");
 406
 407                         bool release = false;
 408                         try {
 409                                 if (exitContext) {
 410 #if !MONOTOUCH
 411                                         SynchronizationAttribute.ExitContext ();
 412 #endif
 413                                 }
 414                                 safe_wait_handle.DangerousAddRef (ref release);
 415                                 return (WaitOne_internal(safe_wait_handle.DangerousGetHandle (), (int) ms, exitContext));
 416                         }
 417                         finally {
 418 #if !MONOTOUCH
 419                                 if (exitContext)
 420                                         SynchronizationAttribute.EnterContext ();
 421 #endif
 422                                 if (release)
 423                                         safe_wait_handle.DangerousRelease ();
 424                         }
 425                 }
 426
 427                 internal void CheckDisposed ()
 428                 {
 429                         if (disposed || safe_wait_handle == null)
 430                                 throw new ObjectDisposedException (GetType ().FullName);
 431                 }
 432
 433                 public static bool WaitAll(WaitHandle[] waitHandles, int millisecondsTimeout)
 434                 {
 435                         return WaitAll (waitHandles, millisecondsTimeout, false);
 436                 }
 437
 438                 public static bool WaitAll(WaitHandle[] waitHandles, TimeSpan timeout)
 439                 {
 440                         return WaitAll (waitHandles, timeout, false);
 441                 }
 442
 443                 protected static readonly IntPtr InvalidHandle = (IntPtr) (-1);
 444                 bool disposed = false;
 445         }
 446 }