mcs/class/System/System.IO/FAMWatcher.cs

   1 //
   2 // System.IO.FAM.cs: interface with libfam
   3 //
   4 // Authors:
   5 //      Gonzalo Paniagua Javier (gonzalo@ximian.com)
   6 //
   7 // (c) 2004 Novell, Inc. (http://www.novell.com)
   8 //
   9
  10 //
  11 // Permission is hereby granted, free of charge, to any person obtaining
  12 // a copy of this software and associated documentation files (the
  13 // "Software"), to deal in the Software without restriction, including
  14 // without limitation the rights to use, copy, modify, merge, publish,
  15 // distribute, sublicense, and/or sell copies of the Software, and to
  16 // permit persons to whom the Software is furnished to do so, subject to
  17 // the following conditions:
  18 //
  19 // The above copyright notice and this permission notice shall be
  20 // included in all copies or substantial portions of the Software.
  21 //
  22 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  23 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  24 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  25 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  26 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  27 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  28 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  29 //
  30
  31 using System;
  32 using System.Collections;
  33 using System.ComponentModel;
  34 using System.Runtime.CompilerServices;
  35 using System.Runtime.InteropServices;
  36 using System.Text;
  37 using System.Threading;
  38
  39 namespace System.IO {
  40         struct FAMConnection {
  41                 public int FD;
  42                 public IntPtr opaque;
  43         }
  44
  45         struct FAMRequest {
  46                 public int ReqNum;
  47         }
  48
  49         enum FAMCodes {
  50                 Changed = 1,
  51                 Deleted = 2,
  52                 StartExecuting = 3,
  53                 StopExecuting = 4,
  54                 Created = 5,
  55                 Moved = 6,
  56                 Acknowledge = 7,
  57                 Exists = 8,
  58                 EndExist = 9
  59         };
  60
  61         class FAMData {
  62                 public FileSystemWatcher FSW;
  63                 public string Directory;
  64                 public string FileMask;
  65                 public bool IncludeSubdirs;
  66                 public bool Enabled;
  67                 public FAMRequest Request;
  68                 public Hashtable SubDirs;
  69         }
  70
  71         class FAMWatcher : IFileWatcher
  72         {
  73                 static bool failed;
  74                 static FAMWatcher instance;
  75                 static Hashtable watches;
  76                 static Hashtable requests;
  77                 static FAMConnection conn;
  78                 static Thread thread;
  79                 static bool stop;
  80                 static bool use_gamin;
  81
  82                 private FAMWatcher ()
  83                 {
  84                 }
  85
  86                 // Locked by caller
  87                 public static bool GetInstance (out IFileWatcher watcher, bool gamin)
  88                 {
  89                         if (failed == true) {
  90                                 watcher = null;
  91                                 return false;
  92                         }
  93
  94                         if (instance != null) {
  95                                 watcher = instance;
  96                                 return true;
  97                         }
  98
  99                         use_gamin = gamin;
 100                         watches = Hashtable.Synchronized (new Hashtable ());
 101                         requests = Hashtable.Synchronized (new Hashtable ());
 102                         if (FAMOpen (out conn) == -1) {
 103                                 failed = true;
 104                                 watcher = null;
 105                                 return false;
 106                         }
 107
 108                         instance = new FAMWatcher ();
 109                         watcher = instance;
 110                         return true;
 111                 }
 112
 113                 public void StartDispatching (FileSystemWatcher fsw)
 114                 {
 115                         FAMData data;
 116                         lock (this) {
 117                                 if (thread == null) {
 118                                         thread = new Thread (new ThreadStart (Monitor));
 119                                         thread.IsBackground = true;
 120                                         thread.Start ();
 121                                 }
 122
 123                                 data = (FAMData) watches [fsw];
 124                         }
 125
 126                         if (data == null) {
 127                                 data = new FAMData ();
 128                                 data.FSW = fsw;
 129                                 data.Directory = fsw.FullPath;
 130                                 data.FileMask = fsw.MangledFilter;
 131                                 data.IncludeSubdirs = fsw.IncludeSubdirectories;
 132                                 if (data.IncludeSubdirs)
 133                                         data.SubDirs = new Hashtable ();
 134
 135                                 data.Enabled = true;
 136                                 StartMonitoringDirectory (data);
 137                                 lock (this) {
 138                                         watches [fsw] = data;
 139                                         requests [data.Request.ReqNum] = data;
 140                                         stop = false;
 141                                 }
 142                         }
 143                 }
 144
 145                 static void StartMonitoringDirectory (FAMData data)
 146                 {
 147                         FAMRequest fr;
 148                         if (FAMMonitorDirectory (ref conn, data.Directory, out fr, IntPtr.Zero) == -1)
 149                                 throw new Win32Exception ();
 150
 151                         data.Request = fr;
 152                         if (!data.IncludeSubdirs)
 153                                 return;
 154
 155                         foreach (string directory in Directory.GetDirectories (data.Directory)) {
 156                                 FAMData fd = new FAMData ();
 157                                 fd.FSW = data.FSW;
 158                                 fd.Directory = directory;
 159                                 fd.FileMask = data.FSW.MangledFilter;
 160                                 fd.IncludeSubdirs = true;
 161                                 fd.SubDirs = new Hashtable ();
 162                                 fd.Enabled = true;
 163
 164                                 StartMonitoringDirectory (fd);
 165                                 data.SubDirs [directory] = fd;
 166                                 requests [fd.Request.ReqNum] = fd;
 167                         }
 168                 }
 169
 170                 public void StopDispatching (FileSystemWatcher fsw)
 171                 {
 172                         FAMData data;
 173                         lock (this) {
 174                                 data = (FAMData) watches [fsw];
 175                                 if (data == null)
 176                                         return;
 177
 178                                 StopMonitoringDirectory (data);
 179                                 watches.Remove (fsw);
 180                                 requests.Remove (data.Request.ReqNum);
 181                                 if (watches.Count == 0)
 182                                         stop = true;
 183
 184                                 if (!data.IncludeSubdirs)
 185                                         return;
 186
 187                                 foreach (FAMData fd in data.SubDirs.Values) {
 188                                         StopMonitoringDirectory (fd);
 189                                         requests.Remove (fd.Request.ReqNum);
 190                                 }
 191                         }
 192                 }
 193
 194                 static void StopMonitoringDirectory (FAMData data)
 195                 {
 196                         if (FAMCancelMonitor (ref conn, ref data.Request) == -1)
 197                                 throw new Win32Exception ();
 198                 }
 199
 200                 void Monitor ()
 201                 {
 202                         while (!stop) {
 203                                 int haveEvents;
 204                                 lock (this) {
 205                                         haveEvents = FAMPending (ref conn);
 206                                 }
 207
 208                                 if (haveEvents > 0) {
 209                                         ProcessEvents ();
 210                                 } else {
 211                                         Thread.Sleep (500);
 212                                 }
 213                         }
 214
 215                         lock (this) {
 216                                 thread = null;
 217                                 stop = false;
 218                         }
 219                 }
 220
 221                 const NotifyFilters changed =   NotifyFilters.Attributes |
 222                                                 NotifyFilters.LastAccess |
 223                                                 NotifyFilters.Size      |
 224                                                 NotifyFilters.LastWrite;
 225
 226                 void ProcessEvents ()
 227                 {
 228                         ArrayList newdirs = null;
 229                         lock (this) {
 230                                 do {
 231                                         int code;
 232                                         string filename;
 233                                         int requestNumber;
 234                                         FileSystemWatcher fsw;
 235
 236                                         if (InternalFAMNextEvent (ref conn, out filename,
 237                                                                   out code, out requestNumber) != 1)
 238                                                 return;
 239
 240                                         bool found = false;
 241                                         switch ((FAMCodes) code) {
 242                                         case FAMCodes.Changed:
 243                                         case FAMCodes.Deleted:
 244                                         case FAMCodes.Created:
 245                                                 found = requests.ContainsKey (requestNumber);
 246                                                 break;
 247                                         case FAMCodes.Moved:
 248                                         case FAMCodes.StartExecuting:
 249                                         case FAMCodes.StopExecuting:
 250                                         case FAMCodes.Acknowledge:
 251                                         case FAMCodes.Exists:
 252                                         case FAMCodes.EndExist:
 253                                         default:
 254                                                 found = false;
 255                                                 break;
 256                                         }
 257
 258                                         if (!found)
 259                                                 continue;
 260
 261                                         FAMData data = (FAMData) requests [requestNumber];
 262                                         if (!data.Enabled)
 263                                                 continue;
 264
 265                                         fsw = data.FSW;
 266                                         NotifyFilters flt = fsw.NotifyFilter;
 267                                         RenamedEventArgs renamed = null;
 268                                         FileAction fa = 0;
 269                                         if (code == (int) FAMCodes.Changed && (flt & changed) != 0)
 270                                                 fa = FileAction.Modified;
 271                                         else if (code == (int) FAMCodes.Deleted)
 272                                                 fa = FileAction.Removed;
 273                                         else if (code == (int) FAMCodes.Created)
 274                                                 fa = FileAction.Added;
 275
 276                                         if (fa == 0)
 277                                                 continue;
 278
 279                                         if (fsw.IncludeSubdirectories) {
 280                                                 string full = fsw.FullPath;
 281                                                 string datadir = data.Directory;
 282                                                 if (datadir != full) {
 283                                                         string reldir = datadir.Substring (full.Length + 1);
 284                                                         datadir = Path.Combine (datadir, filename);
 285                                                         filename = Path.Combine (reldir, filename);
 286                                                 } else {
 287                                                         datadir = Path.Combine (fsw.FullPath, filename);
 288                                                 }
 289
 290                                                 if (fa == FileAction.Added && Directory.Exists (datadir)) {
 291                                                         if (newdirs == null)
 292                                                                 newdirs = new ArrayList (4);
 293
 294                                                         FAMData fd = new FAMData ();
 295                                                         fd.FSW = fsw;
 296                                                         fd.Directory = datadir;
 297                                                         fd.FileMask = fsw.MangledFilter;
 298                                                         fd.IncludeSubdirs = true;
 299                                                         fd.SubDirs = new Hashtable ();
 300                                                         fd.Enabled = true;
 301                                                         newdirs.Add (fd);
 302                                                         newdirs.Add (data);
 303                                                         requests [fd.Request.ReqNum] = fd;
 304                                                 }
 305                                         }
 306
 307                                         if (filename != data.Directory && !fsw.Pattern.IsMatch (filename))
 308                                                 continue;
 309
 310                                         lock (fsw) {
 311                                                 fsw.DispatchEvents (fa, filename, ref renamed);
 312                                                 if (fsw.Waiting) {
 313                                                         fsw.Waiting = false;
 314                                                         System.Threading.Monitor.PulseAll (fsw);
 315                                                 }
 316                                         }
 317                                 } while (FAMPending (ref conn) > 0);
 318                         }
 319
 320
 321                         if (newdirs != null) {
 322                                 int count = newdirs.Count;
 323                                 for (int n = 0; n < count; n += 2) {
 324                                         FAMData newdir = (FAMData) newdirs [n];
 325                                         FAMData parent = (FAMData) newdirs [n + 1];
 326                                         StartMonitoringDirectory (newdir);
 327                                         lock (parent) {
 328                                                 parent.SubDirs [newdir.Directory] = newdir;
 329                                         }
 330                                 }
 331                                 newdirs.Clear ();
 332                         }
 333                 }
 334
 335                 ~FAMWatcher ()
 336                 {
 337                         FAMClose (ref conn);
 338                 }
 339
 340                 static int FAMOpen (out FAMConnection fc)
 341                 {
 342                         if (use_gamin)
 343                                 return gamin_Open (out fc);
 344                         return fam_Open (out fc);
 345                 }
 346
 347                 static int FAMClose (ref FAMConnection fc)
 348                 {
 349                         if (use_gamin)
 350                                 return gamin_Close (ref fc);
 351                         return fam_Close (ref fc);
 352                 }
 353
 354                 static int FAMMonitorDirectory (ref FAMConnection fc, string filename, out FAMRequest fr, IntPtr user_data)
 355                 {
 356                         if (use_gamin)
 357                                 return gamin_MonitorDirectory (ref fc, filename, out fr, user_data);
 358                         return fam_MonitorDirectory (ref fc, filename, out fr, user_data);
 359                 }
 360
 361                 static int FAMCancelMonitor (ref FAMConnection fc, ref FAMRequest fr)
 362                 {
 363                         if (use_gamin)
 364                                 return gamin_CancelMonitor (ref fc, ref fr);
 365                         return fam_CancelMonitor (ref fc, ref fr);
 366                 }
 367
 368                 static int FAMPending (ref FAMConnection fc)
 369                 {
 370                         if (use_gamin)
 371                                 return gamin_Pending (ref fc);
 372                         return fam_Pending (ref fc);
 373                 }
 374
 375
 376
 377                 [DllImport ("libfam.so.0", EntryPoint="FAMOpen")]
 378                 extern static int fam_Open (out FAMConnection fc);
 379
 380                 [DllImport ("libfam.so.0", EntryPoint="FAMClose")]
 381                 extern static int fam_Close (ref FAMConnection fc);
 382
 383                 [DllImport ("libfam.so.0", EntryPoint="FAMMonitorDirectory")]
 384                 extern static int fam_MonitorDirectory (ref FAMConnection fc, string filename,
 385                                                         out FAMRequest fr, IntPtr user_data);
 386
 387                 [DllImport ("libfam.so.0", EntryPoint="FAMCancelMonitor")]
 388                 extern static int fam_CancelMonitor (ref FAMConnection fc, ref FAMRequest fr);
 389
 390                 [DllImport ("libfam.so.0", EntryPoint="FAMPending")]
 391                 extern static int fam_Pending (ref FAMConnection fc);
 392
 393                 [DllImport ("libgamin-1.so.0", EntryPoint="FAMOpen")]
 394                 extern static int gamin_Open (out FAMConnection fc);
 395
 396                 [DllImport ("libgamin-1.so.0", EntryPoint="FAMClose")]
 397                 extern static int gamin_Close (ref FAMConnection fc);
 398
 399                 [DllImport ("libgamin-1.so.0", EntryPoint="FAMMonitorDirectory")]
 400                 extern static int gamin_MonitorDirectory (ref FAMConnection fc, string filename,
 401                                                         out FAMRequest fr, IntPtr user_data);
 402
 403                 [DllImport ("libgamin-1.so.0", EntryPoint="FAMCancelMonitor")]
 404                 extern static int gamin_CancelMonitor (ref FAMConnection fc, ref FAMRequest fr);
 405
 406                 [DllImport ("libgamin-1.so.0", EntryPoint="FAMPending")]
 407                 extern static int gamin_Pending (ref FAMConnection fc);
 408
 409                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 410                 extern static int InternalFAMNextEvent (ref FAMConnection fc, out string filename,
 411                                                         out int code, out int reqnum);
 412
 413         }
 414 }
 415