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
  61                 #endregion // Fields
  62
  63                 #region Constructors
  64
  65                 public FileSystemWatcher ()
  66                 {
  67                         this.notifyFilter = NotifyFilters.LastWrite | NotifyFilters.FileName | NotifyFilters.DirectoryName;
  68                         this.enableRaisingEvents = false;
  69                         this.filter = "*.*";
  70                         this.includeSubdirectories = false;
  71                         this.internalBufferSize = 8192;
  72                         this.path = "";
  73                         InitWatcher ();
  74                 }
  75
  76                 public FileSystemWatcher (string path)
  77                         : this (path, "*.*")
  78                 {
  79                 }
  80
  81                 public FileSystemWatcher (string path, string filter)
  82                 {
  83                         if (path == null)
  84                                 throw new ArgumentNullException ("path");
  85
  86                         if (filter == null)
  87                                 throw new ArgumentNullException ("filter");
  88
  89                         if (path == String.Empty)
  90                                 throw new ArgumentException ("Empty path", "path");
  91
  92                         if (!Directory.Exists (path))
  93                                 throw new ArgumentException ("Directory does not exists", "path");
  94
  95                         this.enableRaisingEvents = false;
  96                         this.filter = filter;
  97                         this.includeSubdirectories = false;
  98                         this.internalBufferSize = 8192;
  99                         this.notifyFilter = NotifyFilters.LastWrite | NotifyFilters.FileName | NotifyFilters.DirectoryName;
 100                         this.path = path;
 101                         this.synchronizingObject = null;
 102                         InitWatcher ();
 103                 }
 104
 105                 void InitWatcher ()
 106                 {
 107                         lock (typeof (FileSystemWatcher)) {
 108                                 if (watcher != null)
 109                                         return;
 110
 111                                 string managed = Environment.GetEnvironmentVariable ("MONO_MANAGED_WATCHER");
 112                                 int mode = 0;
 113                                 if (managed == null)
 114                                         mode = InternalSupportsFSW ();
 115
 116                                 bool ok = false;
 117                                 if (mode == 3)
 118                                         ok = KeventWatcher.GetInstance (out watcher);
 119                                 else if (mode == 2)
 120                                         ok = FAMWatcher.GetInstance (out watcher);
 121                                 else if (mode == 1)
 122                                         ok = DefaultWatcher.GetInstance (out watcher);
 123                                         //ok = WindowsWatcher.GetInstance (out watcher);
 124
 125                                 if (mode == 0 || !ok)
 126                                         DefaultWatcher.GetInstance (out watcher);
 127                         }
 128                 }
 129
 130                 #endregion // Constructors
 131
 132                 #region Properties
 133
 134                 /* If this is enabled, we Pulse this instance */
 135                 internal bool Waiting {
 136                         get { return waiting; }
 137                         set { waiting = value; }
 138                 }
 139
 140                 internal string MangledFilter {
 141                         get {
 142                                 if (filter != "*.*")
 143                                         return filter;
 144
 145                                 if (mangledFilter != null)
 146                                         return mangledFilter;
 147
 148                                 string filterLocal = "*.*";
 149                                 if (!(watcher.GetType () == typeof (WindowsWatcher)))
 150                                         filterLocal = "*";
 151
 152                                 return filterLocal;
 153                         }
 154                 }
 155
 156                 internal SearchPattern2 Pattern {
 157                         get {
 158                                 if (pattern == null) {
 159                                         pattern = new SearchPattern2 (MangledFilter);
 160                                 }
 161                                 return pattern;
 162                         }
 163                 }
 164
 165                 internal string FullPath {
 166                         get {
 167                                 if (fullpath == null) {
 168                                         if (path == null || path == "")
 169                                                 fullpath = Environment.CurrentDirectory;
 170                                         else
 171                                                 fullpath = System.IO.Path.GetFullPath (path);
 172                                 }
 173
 174                                 return fullpath;
 175                         }
 176                 }
 177
 178                 [DefaultValue(false)]
 179                 [IODescription("Flag to indicate if this instance is active")]
 180                 public bool EnableRaisingEvents {
 181                         get { return enableRaisingEvents; }
 182                         set {
 183                                 if (value == enableRaisingEvents)
 184                                         return; // Do nothing
 185
 186                                 enableRaisingEvents = value;
 187                                 if (value) {
 188                                         Start ();
 189                                 } else {
 190                                         Stop ();
 191                                 }
 192                         }
 193                 }
 194
 195                 [DefaultValue("*.*")]
 196                 [IODescription("File name filter pattern")]
 197                 [RecommendedAsConfigurable(true)]
 198                 [TypeConverter ("System.Diagnostics.Design.StringValueConverter, " + Consts.AssemblySystem_Design)]
 199                 public string Filter {
 200                         get { return filter; }
 201                         set {
 202                                 if (value == null || value == "")
 203                                         value = "*.*";
 204
 205                                 if (filter != value) {
 206                                         filter = value;
 207                                         pattern = null;
 208                                         mangledFilter = null;
 209                                 }
 210                         }
 211                 }
 212
 213                 [DefaultValue(false)]
 214                 [IODescription("Flag to indicate we want to watch subdirectories")]
 215                 public bool IncludeSubdirectories {
 216                         get { return includeSubdirectories; }
 217                         set {
 218                                 if (includeSubdirectories == value)
 219                                         return;
 220
 221                                 includeSubdirectories = value;
 222                                 if (value && enableRaisingEvents) {
 223                                         Stop ();
 224                                         Start ();
 225                                 }
 226                         }
 227                 }
 228
 229                 [Browsable(false)]
 230                 [DefaultValue(8192)]
 231                 public int InternalBufferSize {
 232                         get { return internalBufferSize; }
 233                         set {
 234                                 if (internalBufferSize == value)
 235                                         return;
 236
 237                                 if (value < 4196)
 238                                         value = 4196;
 239
 240                                 internalBufferSize = value;
 241                                 if (enableRaisingEvents) {
 242                                         Stop ();
 243                                         Start ();
 244                                 }
 245                         }
 246                 }
 247
 248                 [DefaultValue(NotifyFilters.FileName | NotifyFilters.DirectoryName | NotifyFilters.LastWrite)]
 249                 [IODescription("Flag to indicate which change event we want to monitor")]
 250                 public NotifyFilters NotifyFilter {
 251                         get { return notifyFilter; }
 252                         set {
 253                                 if (notifyFilter == value)
 254                                         return;
 255
 256                                 notifyFilter = value;
 257                                 if (enableRaisingEvents) {
 258                                         Stop ();
 259                                         Start ();
 260                                 }
 261                         }
 262                 }
 263
 264                 [DefaultValue("")]
 265                 [IODescription("The directory to monitor")]
 266                 [RecommendedAsConfigurable(true)]
 267                 [TypeConverter ("System.Diagnostics.Design.StringValueConverter, " + Consts.AssemblySystem_Design)]
 268                 [Editor ("System.Diagnostics.Design.FSWPathEditor, " + Consts.AssemblySystem_Design, "System.Drawing.Design.UITypeEditor, " + Consts.AssemblySystem_Drawing)]
 269                 public string Path {
 270                         get { return path; }
 271                         set {
 272                                 if (path == value)
 273                                         return;
 274
 275                                 bool exists = false;
 276                                 Exception exc = null;
 277
 278                                 try {
 279                                         exists = Directory.Exists (value);
 280                                 } catch (Exception e) {
 281                                         exc = e;
 282                                 }
 283
 284                                 if (exc != null)
 285                                         throw new ArgumentException ("Invalid directory name", "value", exc);
 286
 287                                 if (!exists)
 288                                         throw new ArgumentException ("Directory does not exists", "value");
 289
 290                                 path = value;
 291                                 fullpath = null;
 292                                 if (enableRaisingEvents) {
 293                                         Stop ();
 294                                         Start ();
 295                                 }
 296                         }
 297                 }
 298
 299                 [Browsable(false)]
 300                 public override ISite Site {
 301                         get { return base.Site; }
 302                         set { base.Site = value; }
 303                 }
 304
 305                 [DefaultValue(null)]
 306                 [IODescription("The object used to marshal the event handler calls resulting from a directory change")]
 307                 public ISynchronizeInvoke SynchronizingObject {
 308                         get { return synchronizingObject; }
 309                         set { synchronizingObject = value; }
 310                 }
 311
 312                 #endregion // Properties
 313
 314                 #region Methods
 315
 316                 [MonoTODO]
 317                 public void BeginInit ()
 318                 {
 319                         throw new NotImplementedException ();
 320                 }
 321
 322                 protected override void Dispose (bool disposing)
 323                 {
 324                         if (!disposed) {
 325                                 disposed = true;
 326                                 Stop ();
 327                         }
 328
 329                         base.Dispose (disposing);
 330                 }
 331
 332                 ~FileSystemWatcher ()
 333                 {
 334                         disposed = true;
 335                         Stop ();
 336                 }
 337
 338                 [MonoTODO]
 339                 public void EndInit ()
 340                 {
 341                         throw new NotImplementedException ();
 342                 }
 343
 344                 private void RaiseEvent (Delegate ev, EventArgs arg)
 345                 {
 346                         if (ev == null)
 347                                 return;
 348
 349                         object [] args = new object [] {this, arg};
 350
 351                         if (synchronizingObject == null) {
 352                                 ev.DynamicInvoke (args);
 353                                 return;
 354                         }
 355
 356                         synchronizingObject.BeginInvoke (ev, args);
 357                 }
 358
 359                 protected void OnChanged (FileSystemEventArgs e)
 360                 {
 361                         RaiseEvent (Changed, e);
 362                 }
 363
 364                 protected void OnCreated (FileSystemEventArgs e)
 365                 {
 366                         RaiseEvent (Created, e);
 367                 }
 368
 369                 protected void OnDeleted (FileSystemEventArgs e)
 370                 {
 371                         RaiseEvent (Deleted, e);
 372                 }
 373
 374                 protected void OnError (ErrorEventArgs e)
 375                 {
 376                         RaiseEvent (Error, e);
 377                 }
 378
 379                 protected void OnRenamed (RenamedEventArgs e)
 380                 {
 381                         RaiseEvent (Renamed, e);
 382                 }
 383
 384                 public WaitForChangedResult WaitForChanged (WatcherChangeTypes changeType)
 385                 {
 386                         return WaitForChanged (changeType, Timeout.Infinite);
 387                 }
 388
 389                 public WaitForChangedResult WaitForChanged (WatcherChangeTypes changeType, int timeout)
 390                 {
 391                         WaitForChangedResult result = new WaitForChangedResult ();
 392                         bool prevEnabled = EnableRaisingEvents;
 393                         if (!prevEnabled)
 394                                 EnableRaisingEvents = true;
 395
 396                         bool gotData;
 397                         lock (this) {
 398                                 waiting = true;
 399                                 gotData = Monitor.Wait (this, timeout);
 400                                 if (gotData)
 401                                         result = this.lastData;
 402                         }
 403
 404                         EnableRaisingEvents = prevEnabled;
 405                         if (!gotData)
 406                                 result.TimedOut = true;
 407
 408                         return result;
 409                 }
 410
 411                 internal void DispatchEvents (FileAction act, string filename, ref RenamedEventArgs renamed)
 412                 {
 413                         if (waiting) {
 414                                 lastData = new WaitForChangedResult ();
 415                         }
 416
 417                         switch (act) {
 418                         case FileAction.Added:
 419                                 lastData.Name = filename;
 420                                 lastData.ChangeType = WatcherChangeTypes.Created;
 421                                 OnCreated (new FileSystemEventArgs (WatcherChangeTypes.Created, path, filename));
 422                                 break;
 423                         case FileAction.Removed:
 424                                 lastData.Name = filename;
 425                                 lastData.ChangeType = WatcherChangeTypes.Deleted;
 426                                 OnDeleted (new FileSystemEventArgs (WatcherChangeTypes.Deleted, path, filename));
 427                                 break;
 428                         case FileAction.Modified:
 429                                 lastData.Name = filename;
 430                                 lastData.ChangeType = WatcherChangeTypes.Changed;
 431                                 OnChanged (new FileSystemEventArgs (WatcherChangeTypes.Changed, path, filename));
 432                                 break;
 433                         case FileAction.RenamedOldName:
 434                                 if (renamed != null) {
 435                                         OnRenamed (renamed);
 436                                 }
 437                                 lastData.OldName = filename;
 438                                 lastData.ChangeType = WatcherChangeTypes.Renamed;
 439                                 renamed = new RenamedEventArgs (WatcherChangeTypes.Renamed, path, null, filename);
 440                                 break;
 441                         case FileAction.RenamedNewName:
 442                                 lastData.Name = filename;
 443                                 lastData.ChangeType = WatcherChangeTypes.Renamed;
 444                                 if (renamed != null) {
 445                                         renamed.SetName (filename);
 446                                 } else {
 447                                         renamed = new RenamedEventArgs (WatcherChangeTypes.Renamed, path, filename, null);
 448                                 }
 449                                 OnRenamed (renamed);
 450                                 renamed = null;
 451                                 break;
 452                         default:
 453                                 break;
 454                         }
 455                 }
 456
 457                 void Start ()
 458                 {
 459                         watcher.StartDispatching (this);
 460                 }
 461
 462                 void Stop ()
 463                 {
 464                         watcher.StopDispatching (this);
 465                 }
 466                 #endregion // Methods
 467
 468                 #region Events and Delegates
 469
 470                 [IODescription("Occurs when a file/directory change matches the filter")]
 471                 public event FileSystemEventHandler Changed;
 472
 473                 [IODescription("Occurs when a file/directory creation matches the filter")]
 474                 public event FileSystemEventHandler Created;
 475
 476                 [IODescription("Occurs when a file/directory deletion matches the filter")]
 477                 public event FileSystemEventHandler Deleted;
 478
 479                 [Browsable(false)]
 480                 public event ErrorEventHandler Error;
 481
 482                 [IODescription("Occurs when a file/directory rename matches the filter")]
 483                 public event RenamedEventHandler Renamed;
 484
 485                 #endregion // Events and Delegates
 486
 487                 /* 0 -> not supported   */
 488                 /* 1 -> windows         */
 489                 /* 2 -> FAM             */
 490                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 491                 static extern int InternalSupportsFSW ();
 492
 493                 /*[MethodImplAttribute(MethodImplOptions.InternalCall)]
 494                 static extern IntPtr InternalOpenDirectory (string path, IntPtr reserved);
 495
 496                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 497                 static extern IntPtr InternalCloseDirectory (IntPtr handle);
 498
 499                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 500                 static extern bool InternalReadDirectoryChanges (IntPtr handle,
 501                                                                  byte [] buffer,
 502                                                                  bool includeSubdirectories,
 503                                                                  NotifyFilters notifyFilter,
 504                                                                  out NativeOverlapped overlap,
 505                                                                  OverlappedHandler overlappedCallback);
 506
 507                 */
 508         }
 509 }