mcs/class/System/System.IO/FileSystemWatcher.cs

   1 //
   2 // System.IO.FileSystemWatcher.cs
   3 //
   4 // Authors:
   5 //      Tim Coleman (tim@timcoleman.com)
   6 //      Gonzalo Paniagua Javier (gonzalo@ximian.com)
   7 //
   8 // Copyright (C) Tim Coleman, 2002
   9 // (c) 2003 Ximian, Inc. (http://www.ximian.com)
  10 // (c) 2004 Novell, Inc. (http://www.novell.com)
  11 //
  12
  13 //
  14 // Permission is hereby granted, free of charge, to any person obtaining
  15 // a copy of this software and associated documentation files (the
  16 // "Software"), to deal in the Software without restriction, including
  17 // without limitation the rights to use, copy, modify, merge, publish,
  18 // distribute, sublicense, and/or sell copies of the Software, and to
  19 // permit persons to whom the Software is furnished to do so, subject to
  20 // the following conditions:
  21 //
  22 // The above copyright notice and this permission notice shall be
  23 // included in all copies or substantial portions of the Software.
  24 //
  25 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  26 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  27 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  28 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  29 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  30 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  31 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  32 //
  33
  34 using System;
  35 using System.ComponentModel;
  36 using System.Runtime.CompilerServices;
  37 using System.Runtime.InteropServices;
  38 using System.Threading;
  39
  40 namespace System.IO {
  41         [DefaultEvent("Changed")]
  42         public class FileSystemWatcher : Component, ISupportInitialize {
  43
  44                 #region Fields
  45
  46                 bool enableRaisingEvents;
  47                 string filter;
  48                 bool includeSubdirectories;
  49                 int internalBufferSize;
  50                 NotifyFilters notifyFilter;
  51                 string path;
  52                 string fullpath;
  53                 ISynchronizeInvoke synchronizingObject;
  54                 WaitForChangedResult lastData;
  55                 bool waiting;
  56                 SearchPattern2 pattern;
  57                 bool disposed;
  58                 string mangledFilter;
  59                 static IFileWatcher watcher;
  60                 static object lockobj = new object ();
  61
  62                 #endregion // Fields
  63
  64                 #region Constructors
  65
  66                 public FileSystemWatcher ()
  67                 {
  68                         this.notifyFilter = NotifyFilters.LastWrite | NotifyFilters.FileName | NotifyFilters.DirectoryName;
  69                         this.enableRaisingEvents = false;
  70                         this.filter = "*.*";
  71                         this.includeSubdirectories = false;
  72                         this.internalBufferSize = 8192;
  73                         this.path = "";
  74                         InitWatcher ();
  75                 }
  76
  77                 public FileSystemWatcher (string path)
  78                         : this (path, "*.*")
  79                 {
  80                 }
  81
  82                 public FileSystemWatcher (string path, string filter)
  83                 {
  84                         if (path == null)
  85                                 throw new ArgumentNullException ("path");
  86
  87                         if (filter == null)
  88                                 throw new ArgumentNullException ("filter");
  89
  90                         if (path == String.Empty)
  91                                 throw new ArgumentException ("Empty path", "path");
  92
  93                         if (!Directory.Exists (path))
  94                                 throw new ArgumentException ("Directory does not exists", "path");
  95
  96                         this.enableRaisingEvents = false;
  97                         this.filter = filter;
  98                         this.includeSubdirectories = false;
  99                         this.internalBufferSize = 8192;
 100                         this.notifyFilter = NotifyFilters.LastWrite | NotifyFilters.FileName | NotifyFilters.DirectoryName;
 101                         this.path = path;
 102                         this.synchronizingObject = null;
 103                         InitWatcher ();
 104                 }
 105
 106                 void InitWatcher ()
 107                 {
 108                         lock (lockobj) {
 109                                 if (watcher != null)
 110                                         return;
 111
 112                                 string managed = Environment.GetEnvironmentVariable ("MONO_MANAGED_WATCHER");
 113                                 int mode = 0;
 114                                 if (managed == null)
 115                                         mode = InternalSupportsFSW ();
 116
 117                                 bool ok = false;
 118                                 if (mode == 3)
 119                                         ok = KeventWatcher.GetInstance (out watcher);
 120                                 else if (mode == 2)
 121                                         ok = FAMWatcher.GetInstance (out watcher);
 122                                 else if (mode == 1)
 123                                         ok = DefaultWatcher.GetInstance (out watcher);
 124                                         //ok = WindowsWatcher.GetInstance (out watcher);
 125
 126                                 if (mode == 0 || !ok)
 127                                         DefaultWatcher.GetInstance (out watcher);
 128                         }
 129                 }
 130
 131                 #endregion // Constructors
 132
 133                 #region Properties
 134
 135                 /* If this is enabled, we Pulse this instance */
 136                 internal bool Waiting {
 137                         get { return waiting; }
 138                         set { waiting = value; }
 139                 }
 140
 141                 internal string MangledFilter {
 142                         get {
 143                                 if (filter != "*.*")
 144                                         return filter;
 145
 146                                 if (mangledFilter != null)
 147                                         return mangledFilter;
 148
 149                                 string filterLocal = "*.*";
 150                                 if (!(watcher.GetType () == typeof (WindowsWatcher)))
 151                                         filterLocal = "*";
 152
 153                                 return filterLocal;
 154                         }
 155                 }
 156
 157                 internal SearchPattern2 Pattern {
 158                         get {
 159                                 if (pattern == null) {
 160                                         pattern = new SearchPattern2 (MangledFilter);
 161                                 }
 162                                 return pattern;
 163                         }
 164                 }
 165
 166                 internal string FullPath {
 167                         get {
 168                                 if (fullpath == null) {
 169                                         if (path == null || path == "")
 170                                                 fullpath = Environment.CurrentDirectory;
 171                                         else
 172                                                 fullpath = System.IO.Path.GetFullPath (path);
 173                                 }
 174
 175                                 return fullpath;
 176                         }
 177                 }
 178
 179                 [DefaultValue(false)]
 180                 [IODescription("Flag to indicate if this instance is active")]
 181                 public bool EnableRaisingEvents {
 182                         get { return enableRaisingEvents; }
 183                         set {
 184                                 if (value == enableRaisingEvents)
 185                                         return; // Do nothing
 186
 187                                 enableRaisingEvents = value;
 188                                 if (value) {
 189                                         Start ();
 190                                 } else {
 191                                         Stop ();
 192                                 }
 193                         }
 194                 }
 195
 196                 [DefaultValue("*.*")]
 197                 [IODescription("File name filter pattern")]
 198                 [RecommendedAsConfigurable(true)]
 199                 [TypeConverter ("System.Diagnostics.Design.StringValueConverter, " + Consts.AssemblySystem_Design)]
 200                 public string Filter {
 201                         get { return filter; }
 202                         set {
 203                                 if (value == null || value == "")
 204                                         value = "*.*";
 205
 206                                 if (filter != value) {
 207                                         filter = value;
 208                                         pattern = null;
 209                                         mangledFilter = null;
 210                                 }
 211                         }
 212                 }
 213
 214                 [DefaultValue(false)]
 215                 [IODescription("Flag to indicate we want to watch subdirectories")]
 216                 public bool IncludeSubdirectories {
 217                         get { return includeSubdirectories; }
 218                         set {
 219                                 if (includeSubdirectories == value)
 220                                         return;
 221
 222                                 includeSubdirectories = value;
 223                                 if (value && enableRaisingEvents) {
 224                                         Stop ();
 225                                         Start ();
 226                                 }
 227                         }
 228                 }
 229
 230                 [Browsable(false)]
 231                 [DefaultValue(8192)]
 232                 public int InternalBufferSize {
 233                         get { return internalBufferSize; }
 234                         set {
 235                                 if (internalBufferSize == value)
 236                                         return;
 237
 238                                 if (value < 4196)
 239                                         value = 4196;
 240
 241                                 internalBufferSize = value;
 242                                 if (enableRaisingEvents) {
 243                                         Stop ();
 244                                         Start ();
 245                                 }
 246                         }
 247                 }
 248
 249                 [DefaultValue(NotifyFilters.FileName | NotifyFilters.DirectoryName | NotifyFilters.LastWrite)]
 250                 [IODescription("Flag to indicate which change event we want to monitor")]
 251                 public NotifyFilters NotifyFilter {
 252                         get { return notifyFilter; }
 253                         set {
 254                                 if (notifyFilter == value)
 255                                         return;
 256
 257                                 notifyFilter = value;
 258                                 if (enableRaisingEvents) {
 259                                         Stop ();
 260                                         Start ();
 261                                 }
 262                         }
 263                 }
 264
 265                 [DefaultValue("")]
 266                 [IODescription("The directory to monitor")]
 267                 [RecommendedAsConfigurable(true)]
 268                 [TypeConverter ("System.Diagnostics.Design.StringValueConverter, " + Consts.AssemblySystem_Design)]
 269                 [Editor ("System.Diagnostics.Design.FSWPathEditor, " + Consts.AssemblySystem_Design, "System.Drawing.Design.UITypeEditor, " + Consts.AssemblySystem_Drawing)]
 270                 public string Path {
 271                         get { return path; }
 272                         set {
 273                                 if (path == value)
 274                                         return;
 275
 276                                 bool exists = false;
 277                                 Exception exc = null;
 278
 279                                 try {
 280                                         exists = Directory.Exists (value);
 281                                 } catch (Exception e) {
 282                                         exc = e;
 283                                 }
 284
 285                                 if (exc != null)
 286                                         throw new ArgumentException ("Invalid directory name", "value", exc);
 287
 288                                 if (!exists)
 289                                         throw new ArgumentException ("Directory does not exists", "value");
 290
 291                                 path = value;
 292                                 fullpath = null;
 293                                 if (enableRaisingEvents) {
 294                                         Stop ();
 295                                         Start ();
 296                                 }
 297                         }
 298                 }
 299
 300                 [Browsable(false)]
 301                 public override ISite Site {
 302                         get { return base.Site; }
 303                         set { base.Site = value; }
 304                 }
 305
 306                 [DefaultValue(null)]
 307                 [IODescription("The object used to marshal the event handler calls resulting from a directory change")]
 308                 public ISynchronizeInvoke SynchronizingObject {
 309                         get { return synchronizingObject; }
 310                         set { synchronizingObject = value; }
 311                 }
 312
 313                 #endregion // Properties
 314
 315                 #region Methods
 316
 317                 [MonoTODO]
 318                 public void BeginInit ()
 319                 {
 320                         throw new NotImplementedException ();
 321                 }
 322
 323                 protected override void Dispose (bool disposing)
 324                 {
 325                         if (!disposed) {
 326                                 disposed = true;
 327                                 Stop ();
 328                         }
 329
 330                         base.Dispose (disposing);
 331                 }
 332
 333                 ~FileSystemWatcher ()
 334                 {
 335                         disposed = true;
 336                         Stop ();
 337                 }
 338
 339                 [MonoTODO]
 340                 public void EndInit ()
 341                 {
 342                         throw new NotImplementedException ();
 343                 }
 344
 345                 private void RaiseEvent (Delegate ev, EventArgs arg)
 346                 {
 347                         if (ev == null)
 348                                 return;
 349
 350                         object [] args = new object [] {this, arg};
 351
 352                         if (synchronizingObject == null) {
 353                                 ev.DynamicInvoke (args);
 354                                 return;
 355                         }
 356
 357                         synchronizingObject.BeginInvoke (ev, args);
 358                 }
 359
 360                 protected void OnChanged (FileSystemEventArgs e)
 361                 {
 362                         RaiseEvent (Changed, e);
 363                 }
 364
 365                 protected void OnCreated (FileSystemEventArgs e)
 366                 {
 367                         RaiseEvent (Created, e);
 368                 }
 369
 370                 protected void OnDeleted (FileSystemEventArgs e)
 371                 {
 372                         RaiseEvent (Deleted, e);
 373                 }
 374
 375                 protected void OnError (ErrorEventArgs e)
 376                 {
 377                         RaiseEvent (Error, e);
 378                 }
 379
 380                 protected void OnRenamed (RenamedEventArgs e)
 381                 {
 382                         RaiseEvent (Renamed, e);
 383                 }
 384
 385                 public WaitForChangedResult WaitForChanged (WatcherChangeTypes changeType)
 386                 {
 387                         return WaitForChanged (changeType, Timeout.Infinite);
 388                 }
 389
 390                 public WaitForChangedResult WaitForChanged (WatcherChangeTypes changeType, int timeout)
 391                 {
 392                         WaitForChangedResult result = new WaitForChangedResult ();
 393                         bool prevEnabled = EnableRaisingEvents;
 394                         if (!prevEnabled)
 395                                 EnableRaisingEvents = true;
 396
 397                         bool gotData;
 398                         lock (this) {
 399                                 waiting = true;
 400                                 gotData = Monitor.Wait (this, timeout);
 401                                 if (gotData)
 402                                         result = this.lastData;
 403                         }
 404
 405                         EnableRaisingEvents = prevEnabled;
 406                         if (!gotData)
 407                                 result.TimedOut = true;
 408
 409                         return result;
 410                 }
 411
 412                 internal void DispatchEvents (FileAction act, string filename, ref RenamedEventArgs renamed)
 413                 {
 414                         if (waiting) {
 415                                 lastData = new WaitForChangedResult ();
 416                         }
 417
 418                         switch (act) {
 419                         case FileAction.Added:
 420                                 lastData.Name = filename;
 421                                 lastData.ChangeType = WatcherChangeTypes.Created;
 422                                 OnCreated (new FileSystemEventArgs (WatcherChangeTypes.Created, path, filename));
 423                                 break;
 424                         case FileAction.Removed:
 425                                 lastData.Name = filename;
 426                                 lastData.ChangeType = WatcherChangeTypes.Deleted;
 427                                 OnDeleted (new FileSystemEventArgs (WatcherChangeTypes.Deleted, path, filename));
 428                                 break;
 429                         case FileAction.Modified:
 430                                 lastData.Name = filename;
 431                                 lastData.ChangeType = WatcherChangeTypes.Changed;
 432                                 OnChanged (new FileSystemEventArgs (WatcherChangeTypes.Changed, path, filename));
 433                                 break;
 434                         case FileAction.RenamedOldName:
 435                                 if (renamed != null) {
 436                                         OnRenamed (renamed);
 437                                 }
 438                                 lastData.OldName = filename;
 439                                 lastData.ChangeType = WatcherChangeTypes.Renamed;
 440                                 renamed = new RenamedEventArgs (WatcherChangeTypes.Renamed, path, null, filename);
 441                                 break;
 442                         case FileAction.RenamedNewName:
 443                                 lastData.Name = filename;
 444                                 lastData.ChangeType = WatcherChangeTypes.Renamed;
 445                                 if (renamed != null) {
 446                                         renamed.SetName (filename);
 447                                 } else {
 448                                         renamed = new RenamedEventArgs (WatcherChangeTypes.Renamed, path, filename, null);
 449                                 }
 450                                 OnRenamed (renamed);
 451                                 renamed = null;
 452                                 break;
 453                         default:
 454                                 break;
 455                         }
 456                 }
 457
 458                 void Start ()
 459                 {
 460                         watcher.StartDispatching (this);
 461                 }
 462
 463                 void Stop ()
 464                 {
 465                         watcher.StopDispatching (this);
 466                 }
 467                 #endregion // Methods
 468
 469                 #region Events and Delegates
 470
 471                 [IODescription("Occurs when a file/directory change matches the filter")]
 472                 public event FileSystemEventHandler Changed;
 473
 474                 [IODescription("Occurs when a file/directory creation matches the filter")]
 475                 public event FileSystemEventHandler Created;
 476
 477                 [IODescription("Occurs when a file/directory deletion matches the filter")]
 478                 public event FileSystemEventHandler Deleted;
 479
 480                 [Browsable(false)]
 481                 public event ErrorEventHandler Error;
 482
 483                 [IODescription("Occurs when a file/directory rename matches the filter")]
 484                 public event RenamedEventHandler Renamed;
 485
 486                 #endregion // Events and Delegates
 487
 488                 /* 0 -> not supported   */
 489                 /* 1 -> windows         */
 490                 /* 2 -> FAM             */
 491                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 492                 static extern int InternalSupportsFSW ();
 493
 494                 /*[MethodImplAttribute(MethodImplOptions.InternalCall)]
 495                 static extern IntPtr InternalOpenDirectory (string path, IntPtr reserved);
 496
 497                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 498                 static extern IntPtr InternalCloseDirectory (IntPtr handle);
 499
 500                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 501                 static extern bool InternalReadDirectoryChanges (IntPtr handle,
 502                                                                  byte [] buffer,
 503                                                                  bool includeSubdirectories,
 504                                                                  NotifyFilters notifyFilter,
 505                                                                  out NativeOverlapped overlap,
 506                                                                  OverlappedHandler overlappedCallback);
 507
 508                 */
 509         }
 510 }