mcs/class/corlib/System.Threading.Tasks/Task_T.cs

   1 //
   2 // Task_T.cs
   3 //
   4 // Authors:
   5 //    Marek Safar  <marek.safar@gmail.com>
   6 //
   7 // Copyright (c) 2008 Jérémie "Garuma" Laval
   8 // Copyright 2011 Xamarin Inc.
   9 //
  10 // Permission is hereby granted, free of charge, to any person obtaining a copy
  11 // of this software and associated documentation files (the "Software"), to deal
  12 // in the Software without restriction, including without limitation the rights
  13 // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  14 // copies of the Software, and to permit persons to whom the Software is
  15 // furnished to do so, subject to the following conditions:
  16 //
  17 // The above copyright notice and this permission notice shall be included in
  18 // all copies or substantial portions of the Software.
  19 //
  20 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  21 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  22 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  23 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  24 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  25 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  26 // THE SOFTWARE.
  27 //
  28 //
  29
  30 #if NET_4_0 || MOBILE
  31
  32 using System.Runtime.CompilerServices;
  33
  34 namespace System.Threading.Tasks
  35 {
  36         [System.Diagnostics.DebuggerDisplay ("Id = {Id}, Status = {Status}, Result = {ResultAsString}")]
  37         [System.Diagnostics.DebuggerTypeProxy (typeof (TaskDebuggerView))]
  38         public class Task<TResult> : Task
  39         {
  40                 static readonly TaskFactory<TResult> factory = new TaskFactory<TResult> ();
  41
  42                 TResult value;
  43
  44                 [System.Diagnostics.DebuggerBrowsable (System.Diagnostics.DebuggerBrowsableState.Never)]
  45                 public TResult Result {
  46                         get {
  47                                 if (!IsCompleted)
  48                                         Wait ();
  49                                 if (IsCanceled)
  50                                         throw new AggregateException (new TaskCanceledException (this));
  51                                 if (Exception != null)
  52                                         throw Exception;
  53                                 return value;
  54                         }
  55                         internal set {
  56                                 this.value = value;
  57                         }
  58                 }
  59
  60                 string ResultAsString {
  61                         get {
  62                                 if ((Status & (TaskStatus.RanToCompletion)) != 0)
  63                                         return "" + value;
  64
  65                                 return "<value not available>";
  66                         }
  67                 }
  68
  69                 public static new TaskFactory<TResult> Factory {
  70                         get {
  71                                 return factory;
  72                         }
  73                 }
  74
  75                 public Task (Func<TResult> function)
  76                         : this (function, TaskCreationOptions.None)
  77                 {
  78
  79                 }
  80
  81                 public Task (Func<TResult> function, CancellationToken cancellationToken)
  82                         : this (function, cancellationToken, TaskCreationOptions.None)
  83                 {
  84
  85                 }
  86
  87                 public Task (Func<TResult> function, TaskCreationOptions creationOptions)
  88                         : this (function, CancellationToken.None, creationOptions)
  89                 {
  90
  91                 }
  92
  93                 public Task (Func<TResult> function, CancellationToken cancellationToken, TaskCreationOptions creationOptions)
  94                         : base (TaskActionInvoker.Create (function), null, cancellationToken, creationOptions)
  95                 {
  96                         if (function == null)
  97                                 throw new ArgumentNullException ("function");
  98                 }
  99
 100                 public Task (Func<object, TResult> function, object state)
 101                         : this (function, state, TaskCreationOptions.None)
 102                 {
 103
 104                 }
 105
 106                 public Task (Func<object, TResult> function, object state, CancellationToken cancellationToken)
 107                         : this (function, state, cancellationToken, TaskCreationOptions.None)
 108                 {
 109
 110                 }
 111
 112                 public Task (Func<object, TResult> function, object state, TaskCreationOptions creationOptions)
 113                         : this (function, state, CancellationToken.None, creationOptions)
 114                 {
 115
 116                 }
 117
 118                 public Task (Func<object, TResult> function, object state, CancellationToken cancellationToken, TaskCreationOptions creationOptions)
 119                         : base (TaskActionInvoker.Create (function), state, cancellationToken, creationOptions)
 120                 {
 121                         if (function == null)
 122                                 throw new ArgumentNullException ("function");
 123                 }
 124
 125                 internal Task (TaskActionInvoker invoker, object state, CancellationToken cancellationToken, TaskCreationOptions creationOptions, Task parent, Task contAncestor = null)
 126                         : base (invoker, state, cancellationToken, creationOptions, parent, contAncestor)
 127                 {
 128                 }
 129
 130                 public Task ContinueWith (Action<Task<TResult>> continuationAction)
 131                 {
 132                         return ContinueWith (continuationAction, TaskContinuationOptions.None);
 133                 }
 134
 135                 public Task ContinueWith (Action<Task<TResult>> continuationAction, TaskContinuationOptions continuationOptions)
 136                 {
 137                         return ContinueWith (continuationAction, CancellationToken.None, continuationOptions, TaskScheduler.Current);
 138                 }
 139
 140                 public Task ContinueWith (Action<Task<TResult>> continuationAction, CancellationToken cancellationToken)
 141                 {
 142                         return ContinueWith (continuationAction, cancellationToken, TaskContinuationOptions.None, TaskScheduler.Current);
 143                 }
 144
 145                 public Task ContinueWith (Action<Task<TResult>> continuationAction, TaskScheduler scheduler)
 146                 {
 147                         return ContinueWith (continuationAction, CancellationToken.None, TaskContinuationOptions.None, scheduler);
 148                 }
 149
 150                 public Task ContinueWith (Action<Task<TResult>> continuationAction, CancellationToken cancellationToken,
 151                                           TaskContinuationOptions continuationOptions, TaskScheduler scheduler)
 152                 {
 153                         if (continuationAction == null)
 154                                 throw new ArgumentNullException ("continuationAction");
 155                         if (scheduler == null)
 156                                 throw new ArgumentNullException ("scheduler");
 157
 158                         Task t = new Task (TaskActionInvoker.Create (continuationAction),
 159                                            null,
 160                                            cancellationToken,
 161                                            GetCreationOptions (continuationOptions),
 162                                            null,
 163                                            this);
 164                         ContinueWithCore (t, continuationOptions, scheduler);
 165
 166                         return t;
 167                 }
 168
 169                 public Task<TNewResult> ContinueWith<TNewResult> (Func<Task<TResult>, TNewResult> continuationFunction)
 170                 {
 171                         return ContinueWith<TNewResult> (continuationFunction, CancellationToken.None, TaskContinuationOptions.None, TaskScheduler.Current);
 172                 }
 173
 174                 public Task<TNewResult> ContinueWith<TNewResult> (Func<Task<TResult>, TNewResult> continuationFunction, CancellationToken cancellationToken)
 175                 {
 176                         return ContinueWith<TNewResult> (continuationFunction, cancellationToken, TaskContinuationOptions.None, TaskScheduler.Current);
 177                 }
 178
 179                 public Task<TNewResult> ContinueWith<TNewResult> (Func<Task<TResult>, TNewResult> continuationFunction, TaskContinuationOptions continuationOptions)
 180                 {
 181                         return ContinueWith<TNewResult> (continuationFunction, CancellationToken.None, continuationOptions, TaskScheduler.Current);
 182                 }
 183
 184                 public Task<TNewResult> ContinueWith<TNewResult> (Func<Task<TResult>, TNewResult> continuationFunction, TaskScheduler scheduler)
 185                 {
 186                         return ContinueWith<TNewResult> (continuationFunction, CancellationToken.None, TaskContinuationOptions.None, scheduler);
 187                 }
 188
 189                 public Task<TNewResult> ContinueWith<TNewResult> (Func<Task<TResult>, TNewResult> continuationFunction,
 190                                                                   CancellationToken cancellationToken,
 191                                                                   TaskContinuationOptions continuationOptions,
 192                                                                   TaskScheduler scheduler)
 193                 {
 194                         if (continuationFunction == null)
 195                                 throw new ArgumentNullException ("continuationFunction");
 196                         if (scheduler == null)
 197                                 throw new ArgumentNullException ("scheduler");
 198
 199                         var t = new Task<TNewResult> (TaskActionInvoker.Create (continuationFunction),
 200                                                       null,
 201                                                       cancellationToken,
 202                                                       GetCreationOptions (continuationOptions),
 203                                                       null,
 204                                                       this);
 205                         ContinueWithCore (t, continuationOptions, scheduler);
 206
 207                         return t;
 208                 }
 209
 210                 internal bool TrySetResult (TResult result)
 211                 {
 212                         if (IsCompleted)
 213                                 return false;
 214
 215                         if (!executing.TryRelaxedSet ()) {
 216                                 var sw = new SpinWait ();
 217                                 while (!IsCompleted)
 218                                         sw.SpinOnce ();
 219
 220                                 return false;
 221                         }
 222
 223                         Status = TaskStatus.Running;
 224
 225                         this.value = result;
 226                         Thread.MemoryBarrier ();
 227
 228                         Finish ();
 229
 230                         return true;
 231                 }
 232
 233 #if NET_4_5
 234
 235                 public Task ContinueWith (Action<Task<TResult>, object> continuationAction, object state)
 236                 {
 237                         return ContinueWith (continuationAction, state, CancellationToken.None, TaskContinuationOptions.None, TaskScheduler.Current);
 238                 }
 239
 240                 public Task ContinueWith (Action<Task<TResult>, object> continuationAction, object state, CancellationToken cancellationToken)
 241                 {
 242                         return ContinueWith (continuationAction, state, cancellationToken, TaskContinuationOptions.None, TaskScheduler.Current);
 243                 }
 244
 245                 public Task ContinueWith (Action<Task<TResult>, object> continuationAction, object state, TaskContinuationOptions continuationOptions)
 246                 {
 247                         return ContinueWith (continuationAction, state, CancellationToken.None, continuationOptions, TaskScheduler.Current);
 248                 }
 249
 250                 public Task ContinueWith (Action<Task<TResult>, object> continuationAction, object state, TaskScheduler scheduler)
 251                 {
 252                         return ContinueWith (continuationAction, state, CancellationToken.None, TaskContinuationOptions.None, scheduler);
 253                 }
 254
 255                 public Task ContinueWith (Action<Task<TResult>, object> continuationAction, object state, CancellationToken cancellationToken,
 256                                                                   TaskContinuationOptions continuationOptions, TaskScheduler scheduler)
 257                 {
 258                         if (continuationAction == null)
 259                                 throw new ArgumentNullException ("continuationAction");
 260                         if (scheduler == null)
 261                                 throw new ArgumentNullException ("scheduler");
 262
 263                         var t = new Task (TaskActionInvoker.Create (continuationAction),
 264                                           state,
 265                                           cancellationToken,
 266                                           GetCreationOptions (continuationOptions),
 267                                           null,
 268                                           this);
 269
 270                         ContinueWithCore (t, continuationOptions, scheduler);
 271
 272                         return t;
 273                 }
 274
 275                 public Task<TNewResult> ContinueWith<TNewResult> (Func<Task<TResult>, object, TNewResult> continuationFunction, object state)
 276                 {
 277                         return ContinueWith<TNewResult> (continuationFunction, state, CancellationToken.None, TaskContinuationOptions.None, TaskScheduler.Current);
 278                 }
 279
 280                 public Task<TNewResult> ContinueWith<TNewResult> (Func<Task<TResult>, object, TNewResult> continuationFunction, object state, CancellationToken cancellationToken)
 281                 {
 282                         return ContinueWith<TNewResult> (continuationFunction, state, cancellationToken, TaskContinuationOptions.None, TaskScheduler.Current);
 283                 }
 284
 285                 public Task<TNewResult> ContinueWith<TNewResult> (Func<Task<TResult>, object, TNewResult> continuationFunction, object state, TaskContinuationOptions continuationOptions)
 286                 {
 287                         return ContinueWith<TNewResult> (continuationFunction, state, CancellationToken.None, continuationOptions, TaskScheduler.Current);
 288                 }
 289
 290                 public Task<TNewResult> ContinueWith<TNewResult> (Func<Task<TResult>, object, TNewResult> continuationFunction, object state, TaskScheduler scheduler)
 291                 {
 292                         return ContinueWith<TNewResult> (continuationFunction, state, CancellationToken.None, TaskContinuationOptions.None, scheduler);
 293                 }
 294
 295                 public Task<TNewResult> ContinueWith<TNewResult> (Func<Task<TResult>, object, TNewResult> continuationFunction, object state,
 296                                                                                                                   CancellationToken cancellationToken,
 297                                                                                                                   TaskContinuationOptions continuationOptions,
 298                                                                                                                   TaskScheduler scheduler)
 299                 {
 300                         if (continuationFunction == null)
 301                                 throw new ArgumentNullException ("continuationFunction");
 302                         if (scheduler == null)
 303                                 throw new ArgumentNullException ("scheduler");
 304
 305                         var t = new Task<TNewResult> (TaskActionInvoker.Create (continuationFunction),
 306                                                       state,
 307                                                       cancellationToken,
 308                                                       GetCreationOptions (continuationOptions),
 309                                                       null,
 310                                                       this);
 311
 312                         ContinueWithCore (t, continuationOptions, scheduler);
 313
 314                         return t;
 315                 }
 316
 317                 public new ConfiguredTaskAwaitable<TResult> ConfigureAwait (bool continueOnCapturedContext)
 318                 {
 319                         return new ConfiguredTaskAwaitable<TResult> (this, continueOnCapturedContext);
 320                 }
 321
 322                 public new TaskAwaiter<TResult> GetAwaiter ()
 323                 {
 324                         return new TaskAwaiter<TResult> (this);
 325                 }
 326 #endif
 327         }
 328 }
 329 #endif