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 (handles.Length == 0) {
  58                                 // MS throws different exceptions from the different methods.
  59                                 if (waitAll)
  60                                         throw new ArgumentNullException ("waitHandles");
  61                                 else
  62                                         throw new ArgumentException ();
  63                         }
  64
  65 #if false
  66                         //
  67                         // Although we should thrown an exception if this is an STA thread,
  68                         // Mono does not know anything about STA threads, and just makes
  69                         // things like Paint.NET not even possible to work.
  70                         //
  71                         // See bug #78455 for the bug this is supposed to fix.
  72                         //
  73                         if (waitAll && length > 1 && IsSTAThread)
  74                                 throw new NotSupportedException ("WaitAll for multiple handles is not allowed on an STA thread.");
  75 #endif
  76                         foreach (WaitHandle w in handles) {
  77                                 if (w == null)
  78                                         throw new ArgumentNullException ("waitHandles", "null handle");
  79
  80                                 if (w.safe_wait_handle == null)
  81                                         throw new ArgumentException ("null element found", "waitHandle");
  82
  83                         }
  84                 }
  85 #if false
  86                 // usage of property is commented - see above
  87                 static bool IsSTAThread {
  88                         get {
  89                                 bool isSTA = Thread.CurrentThread.ApartmentState ==
  90                                         ApartmentState.STA;
  91
  92                                 // FIXME: remove this check after Thread.ApartmentState
  93                                 // has been properly implemented.
  94                                 if (!isSTA) {
  95                                         Assembly asm = Assembly.GetEntryAssembly ();
  96                                         if (asm != null)
  97                                                 isSTA = asm.EntryPoint.GetCustomAttributes (typeof (STAThreadAttribute), false).Length > 0;
  98                                 }
  99
 100                                 return isSTA;
 101                         }
 102                 }
 103 #endif
 104                 public static bool WaitAll(WaitHandle[] waitHandles)
 105                 {
 106                         CheckArray (waitHandles, true);
 107                         return(WaitAll_internal(waitHandles, Timeout.Infinite, false));
 108                 }
 109
 110                 public static bool WaitAll(WaitHandle[] waitHandles, int millisecondsTimeout, bool exitContext)
 111                 {
 112                         CheckArray (waitHandles, true);
 113                         // check negative - except for -1 (which is Timeout.Infinite)
 114                         if (millisecondsTimeout < Timeout.Infinite)
 115                                 throw new ArgumentOutOfRangeException ("millisecondsTimeout");
 116
 117                         try {
 118                                 if (exitContext) SynchronizationAttribute.ExitContext ();
 119                                 return(WaitAll_internal(waitHandles, millisecondsTimeout, false));
 120                         }
 121                         finally {
 122                                 if (exitContext) SynchronizationAttribute.EnterContext ();
 123                         }
 124                 }
 125
 126                 public static bool WaitAll(WaitHandle[] waitHandles,
 127                                            TimeSpan timeout,
 128                                            bool exitContext)
 129                 {
 130                         CheckArray (waitHandles, true);
 131                         long ms = (long) timeout.TotalMilliseconds;
 132
 133                         if (ms < -1 || ms > Int32.MaxValue)
 134                                 throw new ArgumentOutOfRangeException ("timeout");
 135
 136                         try {
 137                                 if (exitContext) SynchronizationAttribute.ExitContext ();
 138                                 return (WaitAll_internal (waitHandles, (int) ms, exitContext));
 139                         }
 140                         finally {
 141                                 if (exitContext) SynchronizationAttribute.EnterContext ();
 142                         }
 143                 }
 144
 145                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 146                 private static extern int WaitAny_internal(WaitHandle[] handles, int ms, bool exitContext);
 147
 148                 // LAMESPEC: Doesn't specify how to signal failures
 149                 [ReliabilityContract (Consistency.WillNotCorruptState, Cer.MayFail)]
 150                 public static int WaitAny(WaitHandle[] waitHandles)
 151                 {
 152                         CheckArray (waitHandles, false);
 153                         return(WaitAny_internal(waitHandles, Timeout.Infinite, false));
 154                 }
 155
 156                 [ReliabilityContract (Consistency.WillNotCorruptState, Cer.MayFail)]
 157                 public static int WaitAny(WaitHandle[] waitHandles,
 158                                           int millisecondsTimeout,
 159                                           bool exitContext)
 160                 {
 161                         CheckArray (waitHandles, false);
 162                         // check negative - except for -1 (which is Timeout.Infinite)
 163                         if (millisecondsTimeout < Timeout.Infinite)
 164                                 throw new ArgumentOutOfRangeException ("millisecondsTimeout");
 165
 166                         try {
 167                                 if (exitContext) SynchronizationAttribute.ExitContext ();
 168                                 return(WaitAny_internal(waitHandles, millisecondsTimeout, exitContext));
 169                         }
 170                         finally {
 171                                 if (exitContext) SynchronizationAttribute.EnterContext ();
 172                         }
 173                 }
 174
 175                 [ReliabilityContract (Consistency.WillNotCorruptState, Cer.MayFail)]
 176                 public static int WaitAny(WaitHandle[] waitHandles, TimeSpan timeout)
 177                 {
 178                         return WaitAny (waitHandles, timeout, false);
 179                 }
 180
 181                 [ReliabilityContract (Consistency.WillNotCorruptState, Cer.MayFail)]
 182                 public static int WaitAny(WaitHandle[] waitHandles, int millisecondsTimeout)
 183                 {
 184                         return WaitAny (waitHandles, millisecondsTimeout, false);
 185                 }
 186
 187                 [ReliabilityContract (Consistency.WillNotCorruptState, Cer.MayFail)]
 188                 public static int WaitAny(WaitHandle[] waitHandles,
 189                                           TimeSpan timeout, bool exitContext)
 190                 {
 191                         CheckArray (waitHandles, false);
 192                         long ms = (long) timeout.TotalMilliseconds;
 193
 194                         if (ms < -1 || ms > Int32.MaxValue)
 195                                 throw new ArgumentOutOfRangeException ("timeout");
 196
 197                         try {
 198                                 if (exitContext) SynchronizationAttribute.ExitContext ();
 199                                 return (WaitAny_internal(waitHandles, (int) ms, exitContext));
 200                         }
 201                         finally {
 202                                 if (exitContext) SynchronizationAttribute.EnterContext ();
 203                         }
 204                 }
 205
 206                 protected WaitHandle()
 207                 {
 208                         // FIXME
 209                 }
 210
 211                 public virtual void Close() {
 212                         Dispose(true);
 213                         GC.SuppressFinalize (this);
 214                 }
 215
 216 #if NET_4_0
 217                 public void Dispose ()
 218 #else
 219                 void IDisposable.Dispose ()
 220 #endif
 221                 {
 222                         Close ();
 223                 }
 224
 225                 public const int WaitTimeout = 258;
 226
 227                 //
 228                 // In 2.0 we use SafeWaitHandles instead of IntPtrs
 229                 //
 230                 SafeWaitHandle safe_wait_handle;
 231
 232                 [Obsolete ("In the profiles > 2.x, use SafeHandle instead of Handle")]
 233                 public virtual IntPtr Handle {
 234                         get {
 235                                 return safe_wait_handle.DangerousGetHandle ();
 236                         }
 237
 238                         [SecurityPermission (SecurityAction.LinkDemand, UnmanagedCode = true)]
 239                         [SecurityPermission (SecurityAction.InheritanceDemand, UnmanagedCode = true)]
 240                         set {
 241                                 if (value == InvalidHandle)
 242                                         safe_wait_handle = new SafeWaitHandle (InvalidHandle, false);
 243                                 else
 244                                         safe_wait_handle = new SafeWaitHandle (value, true);
 245                         }
 246                 }
 247
 248                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 249                 private extern bool WaitOne_internal(IntPtr handle, int ms, bool exitContext);
 250
 251                 protected virtual void Dispose (bool explicitDisposing)
 252                 {
 253                         if (!disposed){
 254                                 disposed = true;
 255
 256                                 //
 257                                 // This is only the case if the handle was never properly initialized
 258                                 // most likely a bug in the derived class
 259                                 //
 260                                 if (safe_wait_handle == null)
 261                                         return;
 262
 263                                 lock (this){
 264                                         if (safe_wait_handle != null)
 265                                                 safe_wait_handle.Dispose ();
 266                                 }
 267                         }
 268                 }
 269
 270                 public SafeWaitHandle SafeWaitHandle {
 271                         [ReliabilityContract (Consistency.WillNotCorruptState, Cer.MayFail)]
 272                         get {
 273                                 return safe_wait_handle;
 274                         }
 275
 276                         [ReliabilityContract (Consistency.WillNotCorruptState, Cer.Success)]
 277                         set {
 278                                 if (value == null)
 279                                         safe_wait_handle = new SafeWaitHandle (InvalidHandle, false);
 280                                 else
 281                                         safe_wait_handle = value;
 282                         }
 283                 }
 284
 285                 public static bool SignalAndWait (WaitHandle toSignal,
 286                                                   WaitHandle toWaitOn)
 287                 {
 288                         return SignalAndWait (toSignal, toWaitOn, -1, false);
 289                 }
 290
 291                 public static bool SignalAndWait (WaitHandle toSignal,
 292                                                   WaitHandle toWaitOn,
 293                                                   int millisecondsTimeout,
 294                                                   bool exitContext)
 295                 {
 296                         if (toSignal == null)
 297                                 throw new ArgumentNullException ("toSignal");
 298                         if (toWaitOn == null)
 299                                 throw new ArgumentNullException ("toWaitOn");
 300
 301                         if (millisecondsTimeout < -1)
 302                                 throw new ArgumentOutOfRangeException ("millisecondsTimeout");
 303
 304                         return SignalAndWait_Internal (toSignal.Handle, toWaitOn.Handle, millisecondsTimeout, exitContext);
 305                 }
 306
 307                 public static bool SignalAndWait (WaitHandle toSignal,
 308                                                   WaitHandle toWaitOn,
 309                                                   TimeSpan timeout,
 310                                                   bool exitContext)
 311                 {
 312                         double ms = timeout.TotalMilliseconds;
 313                         if (ms > Int32.MaxValue)
 314                                 throw new ArgumentOutOfRangeException ("timeout");
 315
 316                         return SignalAndWait (toSignal, toWaitOn, Convert.ToInt32 (ms), false);
 317                 }
 318
 319                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 320                 static extern bool SignalAndWait_Internal (IntPtr toSignal, IntPtr toWaitOn, int ms, bool exitContext);
 321
 322                 public virtual bool WaitOne()
 323                 {
 324                         CheckDisposed ();
 325                         bool release = false;
 326                         try {
 327                                 safe_wait_handle.DangerousAddRef (ref release);
 328                                 return (WaitOne_internal(safe_wait_handle.DangerousGetHandle (), Timeout.Infinite, false));
 329                         } finally {
 330                                 if (release)
 331                                         safe_wait_handle.DangerousRelease ();
 332                         }
 333                 }
 334
 335                 public virtual bool WaitOne(int millisecondsTimeout, bool exitContext)
 336                 {
 337                         CheckDisposed ();
 338                         // check negative - except for -1 (which is Timeout.Infinite)
 339                         if (millisecondsTimeout < Timeout.Infinite)
 340                                 throw new ArgumentOutOfRangeException ("millisecondsTimeout");
 341
 342                         bool release = false;
 343                         try {
 344                                 if (exitContext)
 345                                         SynchronizationAttribute.ExitContext ();
 346                                 safe_wait_handle.DangerousAddRef (ref release);
 347                                 return (WaitOne_internal(safe_wait_handle.DangerousGetHandle (), millisecondsTimeout, exitContext));
 348                         } finally {
 349                                 if (exitContext)
 350                                         SynchronizationAttribute.EnterContext ();
 351                                 if (release)
 352                                         safe_wait_handle.DangerousRelease ();
 353                         }
 354                 }
 355
 356                 public virtual bool WaitOne (int millisecondsTimeout)
 357                 {
 358                         return WaitOne (millisecondsTimeout, false);
 359                 }
 360
 361                 public virtual bool WaitOne (TimeSpan timeout)
 362                 {
 363                         return WaitOne (timeout, false);
 364                 }
 365
 366                 public virtual bool WaitOne(TimeSpan timeout, bool exitContext)
 367                 {
 368                         CheckDisposed ();
 369                         long ms = (long) timeout.TotalMilliseconds;
 370                         if (ms < -1 || ms > Int32.MaxValue)
 371                                 throw new ArgumentOutOfRangeException ("timeout");
 372
 373                         bool release = false;
 374                         try {
 375                                 if (exitContext)
 376                                         SynchronizationAttribute.ExitContext ();
 377                                 safe_wait_handle.DangerousAddRef (ref release);
 378                                 return (WaitOne_internal(safe_wait_handle.DangerousGetHandle (), (int) ms, exitContext));
 379                         }
 380                         finally {
 381                                 if (exitContext)
 382                                         SynchronizationAttribute.EnterContext ();
 383                                 if (release)
 384                                         safe_wait_handle.DangerousRelease ();
 385                         }
 386                 }
 387
 388                 internal void CheckDisposed ()
 389                 {
 390                         if (disposed || safe_wait_handle == null)
 391                                 throw new ObjectDisposedException (GetType ().FullName);
 392                 }
 393
 394                 public static bool WaitAll(WaitHandle[] waitHandles, int millisecondsTimeout)
 395                 {
 396                         return WaitAll (waitHandles, millisecondsTimeout, false);
 397                 }
 398
 399                 public static bool WaitAll(WaitHandle[] waitHandles, TimeSpan timeout)
 400                 {
 401                         return WaitAll (waitHandles, timeout, false);
 402                 }
 403
 404                 protected static readonly IntPtr InvalidHandle = (IntPtr) (-1);
 405                 bool disposed = false;
 406
 407                 ~WaitHandle() {
 408                         Dispose(false);
 409                 }
 410         }
 411 }