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.ComponentModel;
  35 using System.Runtime.CompilerServices;
  36 using System.Runtime.InteropServices;
  37 using System.Security.Permissions;
  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                 [EnvironmentPermission (SecurityAction.Assert, Read="MONO_MANAGED_WATCHER")]
 107                 void InitWatcher ()
 108                 {
 109                         lock (lockobj) {
 110                                 if (watcher != null)
 111                                         return;
 112
 113                                 string managed = Environment.GetEnvironmentVariable ("MONO_MANAGED_WATCHER");
 114                                 int mode = 0;
 115                                 if (managed == null)
 116                                         mode = InternalSupportsFSW ();
 117
 118                                 bool ok = false;
 119                                 switch (mode) {
 120                                 case 1: // windows
 121                                         ok = DefaultWatcher.GetInstance (out watcher);
 122                                         //ok = WindowsWatcher.GetInstance (out watcher);
 123                                         break;
 124                                 case 2: // libfam
 125                                         ok = FAMWatcher.GetInstance (out watcher, false);
 126                                         break;
 127                                 case 3: // kevent
 128                                         ok = KeventWatcher.GetInstance (out watcher);
 129                                         break;
 130                                 case 4: // libgamin
 131                                         ok = FAMWatcher.GetInstance (out watcher, true);
 132                                         break;
 133                                 case 5: // inotify
 134                                         ok = InotifyWatcher.GetInstance (out watcher, true);
 135                                         break;
 136                                 }
 137
 138                                 if (mode == 0 || !ok)
 139                                         DefaultWatcher.GetInstance (out watcher);
 140                         }
 141                 }
 142
 143                 #endregion // Constructors
 144
 145                 #region Properties
 146
 147                 /* If this is enabled, we Pulse this instance */
 148                 internal bool Waiting {
 149                         get { return waiting; }
 150                         set { waiting = value; }
 151                 }
 152
 153                 internal string MangledFilter {
 154                         get {
 155                                 if (filter != "*.*")
 156                                         return filter;
 157
 158                                 if (mangledFilter != null)
 159                                         return mangledFilter;
 160
 161                                 string filterLocal = "*.*";
 162                                 if (!(watcher.GetType () == typeof (WindowsWatcher)))
 163                                         filterLocal = "*";
 164
 165                                 return filterLocal;
 166                         }
 167                 }
 168
 169                 internal SearchPattern2 Pattern {
 170                         get {
 171                                 if (pattern == null) {
 172                                         pattern = new SearchPattern2 (MangledFilter);
 173                                 }
 174                                 return pattern;
 175                         }
 176                 }
 177
 178                 internal string FullPath {
 179                         get {
 180                                 if (fullpath == null) {
 181                                         if (path == null || path == "")
 182                                                 fullpath = Environment.CurrentDirectory;
 183                                         else
 184                                                 fullpath = System.IO.Path.GetFullPath (path);
 185                                 }
 186
 187                                 return fullpath;
 188                         }
 189                 }
 190
 191                 [DefaultValue(false)]
 192                 [IODescription("Flag to indicate if this instance is active")]
 193                 public bool EnableRaisingEvents {
 194                         get { return enableRaisingEvents; }
 195                         set {
 196                                 if (value == enableRaisingEvents)
 197                                         return; // Do nothing
 198
 199                                 enableRaisingEvents = value;
 200                                 if (value) {
 201                                         Start ();
 202                                 } else {
 203                                         Stop ();
 204                                 }
 205                         }
 206                 }
 207
 208                 [DefaultValue("*.*")]
 209                 [IODescription("File name filter pattern")]
 210                 [RecommendedAsConfigurable(true)]
 211                 [TypeConverter ("System.Diagnostics.Design.StringValueConverter, " + Consts.AssemblySystem_Design)]
 212                 public string Filter {
 213                         get { return filter; }
 214                         set {
 215                                 if (value == null || value == "")
 216                                         value = "*.*";
 217
 218                                 if (filter != value) {
 219                                         filter = value;
 220                                         pattern = null;
 221                                         mangledFilter = null;
 222                                 }
 223                         }
 224                 }
 225
 226                 [DefaultValue(false)]
 227                 [IODescription("Flag to indicate we want to watch subdirectories")]
 228                 public bool IncludeSubdirectories {
 229                         get { return includeSubdirectories; }
 230                         set {
 231                                 if (includeSubdirectories == value)
 232                                         return;
 233
 234                                 includeSubdirectories = value;
 235                                 if (value && enableRaisingEvents) {
 236                                         Stop ();
 237                                         Start ();
 238                                 }
 239                         }
 240                 }
 241
 242                 [Browsable(false)]
 243                 [DefaultValue(8192)]
 244                 public int InternalBufferSize {
 245                         get { return internalBufferSize; }
 246                         set {
 247                                 if (internalBufferSize == value)
 248                                         return;
 249
 250                                 if (value < 4196)
 251                                         value = 4196;
 252
 253                                 internalBufferSize = value;
 254                                 if (enableRaisingEvents) {
 255                                         Stop ();
 256                                         Start ();
 257                                 }
 258                         }
 259                 }
 260
 261                 [DefaultValue(NotifyFilters.FileName | NotifyFilters.DirectoryName | NotifyFilters.LastWrite)]
 262                 [IODescription("Flag to indicate which change event we want to monitor")]
 263                 public NotifyFilters NotifyFilter {
 264                         get { return notifyFilter; }
 265                         set {
 266                                 if (notifyFilter == value)
 267                                         return;
 268
 269                                 notifyFilter = value;
 270                                 if (enableRaisingEvents) {
 271                                         Stop ();
 272                                         Start ();
 273                                 }
 274                         }
 275                 }
 276
 277                 [DefaultValue("")]
 278                 [IODescription("The directory to monitor")]
 279                 [RecommendedAsConfigurable(true)]
 280                 [TypeConverter ("System.Diagnostics.Design.StringValueConverter, " + Consts.AssemblySystem_Design)]
 281                 [Editor ("System.Diagnostics.Design.FSWPathEditor, " + Consts.AssemblySystem_Design, "System.Drawing.Design.UITypeEditor, " + Consts.AssemblySystem_Drawing)]
 282                 public string Path {
 283                         get { return path; }
 284                         set {
 285                                 if (path == value)
 286                                         return;
 287
 288                                 bool exists = false;
 289                                 Exception exc = null;
 290
 291                                 try {
 292                                         exists = Directory.Exists (value);
 293                                 } catch (Exception e) {
 294                                         exc = e;
 295                                 }
 296
 297                                 if (exc != null)
 298                                         throw new ArgumentException ("Invalid directory name", "value", exc);
 299
 300                                 if (!exists)
 301                                         throw new ArgumentException ("Directory does not exists", "value");
 302
 303                                 path = value;
 304                                 fullpath = null;
 305                                 if (enableRaisingEvents) {
 306                                         Stop ();
 307                                         Start ();
 308                                 }
 309                         }
 310                 }
 311
 312                 [Browsable(false)]
 313                 public override ISite Site {
 314                         get { return base.Site; }
 315                         set { base.Site = value; }
 316                 }
 317
 318                 [DefaultValue(null)]
 319                 [IODescription("The object used to marshal the event handler calls resulting from a directory change")]
 320                 public ISynchronizeInvoke SynchronizingObject {
 321                         get { return synchronizingObject; }
 322                         set { synchronizingObject = value; }
 323                 }
 324
 325                 #endregion // Properties
 326
 327                 #region Methods
 328
 329                 [MonoTODO]
 330                 public void BeginInit ()
 331                 {
 332                         throw new NotImplementedException ();
 333                 }
 334
 335                 protected override void Dispose (bool disposing)
 336                 {
 337                         if (!disposed) {
 338                                 disposed = true;
 339                                 Stop ();
 340                         }
 341
 342                         base.Dispose (disposing);
 343                 }
 344
 345                 ~FileSystemWatcher ()
 346                 {
 347                         disposed = true;
 348                         Stop ();
 349                 }
 350
 351                 [MonoTODO]
 352                 public void EndInit ()
 353                 {
 354                         throw new NotImplementedException ();
 355                 }
 356
 357                 private void RaiseEvent (Delegate ev, EventArgs arg)
 358                 {
 359                         if (ev == null)
 360                                 return;
 361
 362                         object [] args = new object [] {this, arg};
 363
 364                         if (synchronizingObject == null) {
 365                                 ev.DynamicInvoke (args);
 366                                 return;
 367                         }
 368
 369                         synchronizingObject.BeginInvoke (ev, args);
 370                 }
 371
 372                 protected void OnChanged (FileSystemEventArgs e)
 373                 {
 374                         RaiseEvent (Changed, e);
 375                 }
 376
 377                 protected void OnCreated (FileSystemEventArgs e)
 378                 {
 379                         RaiseEvent (Created, e);
 380                 }
 381
 382                 protected void OnDeleted (FileSystemEventArgs e)
 383                 {
 384                         RaiseEvent (Deleted, e);
 385                 }
 386
 387                 protected void OnError (ErrorEventArgs e)
 388                 {
 389                         RaiseEvent (Error, e);
 390                 }
 391
 392                 protected void OnRenamed (RenamedEventArgs e)
 393                 {
 394                         RaiseEvent (Renamed, e);
 395                 }
 396
 397                 public WaitForChangedResult WaitForChanged (WatcherChangeTypes changeType)
 398                 {
 399                         return WaitForChanged (changeType, Timeout.Infinite);
 400                 }
 401
 402                 public WaitForChangedResult WaitForChanged (WatcherChangeTypes changeType, int timeout)
 403                 {
 404                         WaitForChangedResult result = new WaitForChangedResult ();
 405                         bool prevEnabled = EnableRaisingEvents;
 406                         if (!prevEnabled)
 407                                 EnableRaisingEvents = true;
 408
 409                         bool gotData;
 410                         lock (this) {
 411                                 waiting = true;
 412                                 gotData = Monitor.Wait (this, timeout);
 413                                 if (gotData)
 414                                         result = this.lastData;
 415                         }
 416
 417                         EnableRaisingEvents = prevEnabled;
 418                         if (!gotData)
 419                                 result.TimedOut = true;
 420
 421                         return result;
 422                 }
 423
 424                 internal void DispatchEvents (FileAction act, string filename, ref RenamedEventArgs renamed)
 425                 {
 426                         if (waiting) {
 427                                 lastData = new WaitForChangedResult ();
 428                         }
 429
 430                         switch (act) {
 431                         case FileAction.Added:
 432                                 lastData.Name = filename;
 433                                 lastData.ChangeType = WatcherChangeTypes.Created;
 434                                 OnCreated (new FileSystemEventArgs (WatcherChangeTypes.Created, path, filename));
 435                                 break;
 436                         case FileAction.Removed:
 437                                 lastData.Name = filename;
 438                                 lastData.ChangeType = WatcherChangeTypes.Deleted;
 439                                 OnDeleted (new FileSystemEventArgs (WatcherChangeTypes.Deleted, path, filename));
 440                                 break;
 441                         case FileAction.Modified:
 442                                 lastData.Name = filename;
 443                                 lastData.ChangeType = WatcherChangeTypes.Changed;
 444                                 OnChanged (new FileSystemEventArgs (WatcherChangeTypes.Changed, path, filename));
 445                                 break;
 446                         case FileAction.RenamedOldName:
 447                                 if (renamed != null) {
 448                                         OnRenamed (renamed);
 449                                 }
 450                                 lastData.OldName = filename;
 451                                 lastData.ChangeType = WatcherChangeTypes.Renamed;
 452                                 renamed = new RenamedEventArgs (WatcherChangeTypes.Renamed, path, filename, "");
 453                                 break;
 454                         case FileAction.RenamedNewName:
 455                                 lastData.Name = filename;
 456                                 lastData.ChangeType = WatcherChangeTypes.Renamed;
 457                                 if (renamed != null) {
 458                                         renamed.SetName (filename);
 459                                 } else {
 460                                         renamed = new RenamedEventArgs (WatcherChangeTypes.Renamed, path, "", filename);
 461                                 }
 462                                 OnRenamed (renamed);
 463                                 renamed = null;
 464                                 break;
 465                         default:
 466                                 break;
 467                         }
 468                 }
 469
 470                 void Start ()
 471                 {
 472                         watcher.StartDispatching (this);
 473                 }
 474
 475                 void Stop ()
 476                 {
 477                         watcher.StopDispatching (this);
 478                 }
 479                 #endregion // Methods
 480
 481                 #region Events and Delegates
 482
 483                 [IODescription("Occurs when a file/directory change matches the filter")]
 484                 public event FileSystemEventHandler Changed;
 485
 486                 [IODescription("Occurs when a file/directory creation matches the filter")]
 487                 public event FileSystemEventHandler Created;
 488
 489                 [IODescription("Occurs when a file/directory deletion matches the filter")]
 490                 public event FileSystemEventHandler Deleted;
 491
 492                 [Browsable(false)]
 493                 public event ErrorEventHandler Error;
 494
 495                 [IODescription("Occurs when a file/directory rename matches the filter")]
 496                 public event RenamedEventHandler Renamed;
 497
 498                 #endregion // Events and Delegates
 499
 500                 /* 0 -> not supported   */
 501                 /* 1 -> windows         */
 502                 /* 2 -> FAM             */
 503                 /* 3 -> Kevent          */
 504                 /* 4 -> gamin           */
 505                 /* 5 -> inotify         */
 506                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 507                 static extern int InternalSupportsFSW ();
 508         }
 509 }
 510