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                                 switch (mode) {
 119                                 case 1: // windows
 120                                         ok = DefaultWatcher.GetInstance (out watcher);
 121                                         //ok = WindowsWatcher.GetInstance (out watcher);
 122                                         break;
 123                                 case 2: // libfam
 124                                         ok = FAMWatcher.GetInstance (out watcher, false);
 125                                         break;
 126                                 case 3: // kevent
 127                                         ok = KeventWatcher.GetInstance (out watcher);
 128                                         break;
 129                                 case 4: // libgamin
 130                                         ok = FAMWatcher.GetInstance (out watcher, true);
 131                                         break;
 132                                 }
 133
 134                                 if (mode == 0 || !ok)
 135                                         DefaultWatcher.GetInstance (out watcher);
 136                         }
 137                 }
 138
 139                 #endregion // Constructors
 140
 141                 #region Properties
 142
 143                 /* If this is enabled, we Pulse this instance */
 144                 internal bool Waiting {
 145                         get { return waiting; }
 146                         set { waiting = value; }
 147                 }
 148
 149                 internal string MangledFilter {
 150                         get {
 151                                 if (filter != "*.*")
 152                                         return filter;
 153
 154                                 if (mangledFilter != null)
 155                                         return mangledFilter;
 156
 157                                 string filterLocal = "*.*";
 158                                 if (!(watcher.GetType () == typeof (WindowsWatcher)))
 159                                         filterLocal = "*";
 160
 161                                 return filterLocal;
 162                         }
 163                 }
 164
 165                 internal SearchPattern2 Pattern {
 166                         get {
 167                                 if (pattern == null) {
 168                                         pattern = new SearchPattern2 (MangledFilter);
 169                                 }
 170                                 return pattern;
 171                         }
 172                 }
 173
 174                 internal string FullPath {
 175                         get {
 176                                 if (fullpath == null) {
 177                                         if (path == null || path == "")
 178                                                 fullpath = Environment.CurrentDirectory;
 179                                         else
 180                                                 fullpath = System.IO.Path.GetFullPath (path);
 181                                 }
 182
 183                                 return fullpath;
 184                         }
 185                 }
 186
 187                 [DefaultValue(false)]
 188                 [IODescription("Flag to indicate if this instance is active")]
 189                 public bool EnableRaisingEvents {
 190                         get { return enableRaisingEvents; }
 191                         set {
 192                                 if (value == enableRaisingEvents)
 193                                         return; // Do nothing
 194
 195                                 enableRaisingEvents = value;
 196                                 if (value) {
 197                                         Start ();
 198                                 } else {
 199                                         Stop ();
 200                                 }
 201                         }
 202                 }
 203
 204                 [DefaultValue("*.*")]
 205                 [IODescription("File name filter pattern")]
 206                 [RecommendedAsConfigurable(true)]
 207                 [TypeConverter ("System.Diagnostics.Design.StringValueConverter, " + Consts.AssemblySystem_Design)]
 208                 public string Filter {
 209                         get { return filter; }
 210                         set {
 211                                 if (value == null || value == "")
 212                                         value = "*.*";
 213
 214                                 if (filter != value) {
 215                                         filter = value;
 216                                         pattern = null;
 217                                         mangledFilter = null;
 218                                 }
 219                         }
 220                 }
 221
 222                 [DefaultValue(false)]
 223                 [IODescription("Flag to indicate we want to watch subdirectories")]
 224                 public bool IncludeSubdirectories {
 225                         get { return includeSubdirectories; }
 226                         set {
 227                                 if (includeSubdirectories == value)
 228                                         return;
 229
 230                                 includeSubdirectories = value;
 231                                 if (value && enableRaisingEvents) {
 232                                         Stop ();
 233                                         Start ();
 234                                 }
 235                         }
 236                 }
 237
 238                 [Browsable(false)]
 239                 [DefaultValue(8192)]
 240                 public int InternalBufferSize {
 241                         get { return internalBufferSize; }
 242                         set {
 243                                 if (internalBufferSize == value)
 244                                         return;
 245
 246                                 if (value < 4196)
 247                                         value = 4196;
 248
 249                                 internalBufferSize = value;
 250                                 if (enableRaisingEvents) {
 251                                         Stop ();
 252                                         Start ();
 253                                 }
 254                         }
 255                 }
 256
 257                 [DefaultValue(NotifyFilters.FileName | NotifyFilters.DirectoryName | NotifyFilters.LastWrite)]
 258                 [IODescription("Flag to indicate which change event we want to monitor")]
 259                 public NotifyFilters NotifyFilter {
 260                         get { return notifyFilter; }
 261                         set {
 262                                 if (notifyFilter == value)
 263                                         return;
 264
 265                                 notifyFilter = value;
 266                                 if (enableRaisingEvents) {
 267                                         Stop ();
 268                                         Start ();
 269                                 }
 270                         }
 271                 }
 272
 273                 [DefaultValue("")]
 274                 [IODescription("The directory to monitor")]
 275                 [RecommendedAsConfigurable(true)]
 276                 [TypeConverter ("System.Diagnostics.Design.StringValueConverter, " + Consts.AssemblySystem_Design)]
 277                 [Editor ("System.Diagnostics.Design.FSWPathEditor, " + Consts.AssemblySystem_Design, "System.Drawing.Design.UITypeEditor, " + Consts.AssemblySystem_Drawing)]
 278                 public string Path {
 279                         get { return path; }
 280                         set {
 281                                 if (path == value)
 282                                         return;
 283
 284                                 bool exists = false;
 285                                 Exception exc = null;
 286
 287                                 try {
 288                                         exists = Directory.Exists (value);
 289                                 } catch (Exception e) {
 290                                         exc = e;
 291                                 }
 292
 293                                 if (exc != null)
 294                                         throw new ArgumentException ("Invalid directory name", "value", exc);
 295
 296                                 if (!exists)
 297                                         throw new ArgumentException ("Directory does not exists", "value");
 298
 299                                 path = value;
 300                                 fullpath = null;
 301                                 if (enableRaisingEvents) {
 302                                         Stop ();
 303                                         Start ();
 304                                 }
 305                         }
 306                 }
 307
 308                 [Browsable(false)]
 309                 public override ISite Site {
 310                         get { return base.Site; }
 311                         set { base.Site = value; }
 312                 }
 313
 314                 [DefaultValue(null)]
 315                 [IODescription("The object used to marshal the event handler calls resulting from a directory change")]
 316                 public ISynchronizeInvoke SynchronizingObject {
 317                         get { return synchronizingObject; }
 318                         set { synchronizingObject = value; }
 319                 }
 320
 321                 #endregion // Properties
 322
 323                 #region Methods
 324
 325                 [MonoTODO]
 326                 public void BeginInit ()
 327                 {
 328                         throw new NotImplementedException ();
 329                 }
 330
 331                 protected override void Dispose (bool disposing)
 332                 {
 333                         if (!disposed) {
 334                                 disposed = true;
 335                                 Stop ();
 336                         }
 337
 338                         base.Dispose (disposing);
 339                 }
 340
 341                 ~FileSystemWatcher ()
 342                 {
 343                         disposed = true;
 344                         Stop ();
 345                 }
 346
 347                 [MonoTODO]
 348                 public void EndInit ()
 349                 {
 350                         throw new NotImplementedException ();
 351                 }
 352
 353                 private void RaiseEvent (Delegate ev, EventArgs arg)
 354                 {
 355                         if (ev == null)
 356                                 return;
 357
 358                         object [] args = new object [] {this, arg};
 359
 360                         if (synchronizingObject == null) {
 361                                 ev.DynamicInvoke (args);
 362                                 return;
 363                         }
 364
 365                         synchronizingObject.BeginInvoke (ev, args);
 366                 }
 367
 368                 protected void OnChanged (FileSystemEventArgs e)
 369                 {
 370                         RaiseEvent (Changed, e);
 371                 }
 372
 373                 protected void OnCreated (FileSystemEventArgs e)
 374                 {
 375                         RaiseEvent (Created, e);
 376                 }
 377
 378                 protected void OnDeleted (FileSystemEventArgs e)
 379                 {
 380                         RaiseEvent (Deleted, e);
 381                 }
 382
 383                 protected void OnError (ErrorEventArgs e)
 384                 {
 385                         RaiseEvent (Error, e);
 386                 }
 387
 388                 protected void OnRenamed (RenamedEventArgs e)
 389                 {
 390                         RaiseEvent (Renamed, e);
 391                 }
 392
 393                 public WaitForChangedResult WaitForChanged (WatcherChangeTypes changeType)
 394                 {
 395                         return WaitForChanged (changeType, Timeout.Infinite);
 396                 }
 397
 398                 public WaitForChangedResult WaitForChanged (WatcherChangeTypes changeType, int timeout)
 399                 {
 400                         WaitForChangedResult result = new WaitForChangedResult ();
 401                         bool prevEnabled = EnableRaisingEvents;
 402                         if (!prevEnabled)
 403                                 EnableRaisingEvents = true;
 404
 405                         bool gotData;
 406                         lock (this) {
 407                                 waiting = true;
 408                                 gotData = Monitor.Wait (this, timeout);
 409                                 if (gotData)
 410                                         result = this.lastData;
 411                         }
 412
 413                         EnableRaisingEvents = prevEnabled;
 414                         if (!gotData)
 415                                 result.TimedOut = true;
 416
 417                         return result;
 418                 }
 419
 420                 internal void DispatchEvents (FileAction act, string filename, ref RenamedEventArgs renamed)
 421                 {
 422                         if (waiting) {
 423                                 lastData = new WaitForChangedResult ();
 424                         }
 425
 426                         switch (act) {
 427                         case FileAction.Added:
 428                                 lastData.Name = filename;
 429                                 lastData.ChangeType = WatcherChangeTypes.Created;
 430                                 OnCreated (new FileSystemEventArgs (WatcherChangeTypes.Created, path, filename));
 431                                 break;
 432                         case FileAction.Removed:
 433                                 lastData.Name = filename;
 434                                 lastData.ChangeType = WatcherChangeTypes.Deleted;
 435                                 OnDeleted (new FileSystemEventArgs (WatcherChangeTypes.Deleted, path, filename));
 436                                 break;
 437                         case FileAction.Modified:
 438                                 lastData.Name = filename;
 439                                 lastData.ChangeType = WatcherChangeTypes.Changed;
 440                                 OnChanged (new FileSystemEventArgs (WatcherChangeTypes.Changed, path, filename));
 441                                 break;
 442                         case FileAction.RenamedOldName:
 443                                 if (renamed != null) {
 444                                         OnRenamed (renamed);
 445                                 }
 446                                 lastData.OldName = filename;
 447                                 lastData.ChangeType = WatcherChangeTypes.Renamed;
 448                                 renamed = new RenamedEventArgs (WatcherChangeTypes.Renamed, path, null, filename);
 449                                 break;
 450                         case FileAction.RenamedNewName:
 451                                 lastData.Name = filename;
 452                                 lastData.ChangeType = WatcherChangeTypes.Renamed;
 453                                 if (renamed != null) {
 454                                         renamed.SetName (filename);
 455                                 } else {
 456                                         renamed = new RenamedEventArgs (WatcherChangeTypes.Renamed, path, filename, null);
 457                                 }
 458                                 OnRenamed (renamed);
 459                                 renamed = null;
 460                                 break;
 461                         default:
 462                                 break;
 463                         }
 464                 }
 465
 466                 void Start ()
 467                 {
 468                         watcher.StartDispatching (this);
 469                 }
 470
 471                 void Stop ()
 472                 {
 473                         watcher.StopDispatching (this);
 474                 }
 475                 #endregion // Methods
 476
 477                 #region Events and Delegates
 478
 479                 [IODescription("Occurs when a file/directory change matches the filter")]
 480                 public event FileSystemEventHandler Changed;
 481
 482                 [IODescription("Occurs when a file/directory creation matches the filter")]
 483                 public event FileSystemEventHandler Created;
 484
 485                 [IODescription("Occurs when a file/directory deletion matches the filter")]
 486                 public event FileSystemEventHandler Deleted;
 487
 488                 [Browsable(false)]
 489                 public event ErrorEventHandler Error;
 490
 491                 [IODescription("Occurs when a file/directory rename matches the filter")]
 492                 public event RenamedEventHandler Renamed;
 493
 494                 #endregion // Events and Delegates
 495
 496                 /* 0 -> not supported   */
 497                 /* 1 -> windows         */
 498                 /* 2 -> FAM             */
 499                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 500                 static extern int InternalSupportsFSW ();
 501
 502                 /*[MethodImplAttribute(MethodImplOptions.InternalCall)]
 503                 static extern IntPtr InternalOpenDirectory (string path, IntPtr reserved);
 504
 505                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 506                 static extern IntPtr InternalCloseDirectory (IntPtr handle);
 507
 508                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 509                 static extern bool InternalReadDirectoryChanges (IntPtr handle,
 510                                                                  byte [] buffer,
 511                                                                  bool includeSubdirectories,
 512                                                                  NotifyFilters notifyFilter,
 513                                                                  out NativeOverlapped overlap,
 514                                                                  OverlappedHandler overlappedCallback);
 515
 516                 */
 517         }
 518 }