mcs/class/corlib/System.Runtime.Remoting/RemotingServices.cs

   1 //
   2 // System.Runtime.Remoting.RemotingServices.cs
   3 //
   4 // Authors:
   5 //   Dietmar Maurer (dietmar@ximian.com)
   6 //   Lluis Sanchez Gual (lluis@ideary.com)
   7 //   Patrik Torstensson
   8 //
   9 // (C) 2001 Ximian, Inc.  http://www.ximian.com
  10 //
  11
  12 using System;
  13 using System.Text;
  14 using System.Reflection;
  15 using System.Threading;
  16 using System.Collections;
  17 using System.Runtime.Remoting.Messaging;
  18 using System.Runtime.Remoting.Proxies;
  19 using System.Runtime.Remoting.Channels;
  20 using System.Runtime.Remoting.Contexts;
  21 using System.Runtime.Remoting.Activation;
  22 using System.Runtime.Remoting.Lifetime;
  23 using System.Runtime.CompilerServices;
  24 using System.Runtime.Serialization;
  25 using System.IO;
  26
  27 namespace System.Runtime.Remoting
  28 {
  29         public sealed class RemotingServices
  30         {
  31                 // Holds the identities of the objects, using uri as index
  32                 static Hashtable uri_hash = new Hashtable ();
  33
  34                 internal static string app_id;
  35                 static int next_id = 1;
  36
  37                 static RemotingServices ()
  38                 {
  39                         RegisterInternalChannels ();
  40                         app_id = Guid.NewGuid().ToString().Replace('-', '_') + "/";
  41                         CreateWellKnownServerIdentity (typeof(RemoteActivator), "RemoteActivationService.rem", WellKnownObjectMode.Singleton);
  42                 }
  43
  44                 private RemotingServices () {}
  45
  46                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
  47                 internal extern static object InternalExecute (MonoMethod method, Object obj,
  48                                                                Object[] parameters, out object [] out_args);
  49
  50                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
  51                 public extern static bool IsTransparentProxy (object proxy);
  52
  53                 internal static IMethodReturnMessage InternalExecuteMessage (
  54                         MarshalByRefObject target, IMethodCallMessage reqMsg)
  55                 {
  56                         ReturnMessage result;
  57
  58                         MonoMethod method = (MonoMethod) target.GetType().GetMethod(reqMsg.MethodName, BindingFlags.Public|BindingFlags.NonPublic|BindingFlags.Instance, null, (Type[]) reqMsg.MethodSignature, null);
  59                         object oldContext = CallContext.SetCurrentCallContext (reqMsg.LogicalCallContext);
  60
  61                         try
  62                         {
  63                                 object [] out_args;
  64                                 object rval = InternalExecute (method, target, reqMsg.Args, out out_args);
  65
  66                                 // Collect parameters with Out flag from the request message
  67
  68                                 ParameterInfo[] parameters = method.GetParameters();
  69                                 object[] returnArgs = new object [parameters.Length];
  70
  71                                 int n = 0;
  72                                 int noa = 0;
  73                                 foreach (ParameterInfo par in parameters)
  74                                 {
  75                                         if (par.IsOut && !par.ParameterType.IsByRef)
  76                                                 returnArgs [n++] = reqMsg.GetArg (par.Position);
  77                                         else if (par.ParameterType.IsByRef)
  78                                                 returnArgs [n++] = out_args [noa++];
  79                                 }
  80
  81                                 result = new ReturnMessage (rval, returnArgs, n, CallContext.CreateLogicalCallContext(), reqMsg);
  82                         }
  83                         catch (Exception e)
  84                         {
  85                                 result = new ReturnMessage (e, reqMsg);
  86                         }
  87
  88                         CallContext.RestoreCallContext (oldContext);
  89                         return result;
  90                 }
  91
  92                 public static IMethodReturnMessage ExecuteMessage (
  93                         MarshalByRefObject target, IMethodCallMessage reqMsg)
  94                 {
  95                         if (IsTransparentProxy(target))
  96                         {
  97                                 // Message must go through all chain of sinks
  98                                 RealProxy rp = GetRealProxy (target);
  99                                 return (IMethodReturnMessage) rp.Invoke (reqMsg);
 100                         }
 101                         else    // Direct call
 102                                 return InternalExecuteMessage (target, reqMsg);
 103                 }
 104
 105                 public static object Connect (Type classToProxy, string url)
 106                 {
 107                         ObjRef objRef = new ObjRef (classToProxy, url, null);
 108                         return GetRemoteObject (objRef, classToProxy);
 109                 }
 110
 111                 public static object Connect (Type classToProxy, string url, object data)
 112                 {
 113                         ObjRef objRef = new ObjRef (classToProxy, url, data);
 114                         return GetRemoteObject (objRef, classToProxy);
 115                 }
 116
 117                 public static bool Disconnect (MarshalByRefObject obj)
 118                 {
 119                         if (obj == null) throw new ArgumentNullException ("obj");
 120
 121                         ServerIdentity identity;
 122
 123                         if (IsTransparentProxy (obj))
 124                         {
 125                                 // CBOs are always accessed through a proxy, even in the server, so
 126                                 // for server CBOs it is ok to disconnect a proxy
 127
 128                                 RealProxy proxy = GetRealProxy(obj);
 129                                 if (proxy.GetProxiedType().IsContextful && (proxy.ObjectIdentity is ServerIdentity))
 130                                         identity = proxy.ObjectIdentity as ServerIdentity;
 131                                 else
 132                                         throw new ArgumentException ("The obj parameter is a proxy");
 133                         }
 134                         else
 135                                 identity = obj.ObjectIdentity;
 136
 137                         if (identity == null || !identity.IsConnected)
 138                                 return false;
 139                         else
 140                         {
 141                                 LifetimeServices.StopTrackingLifetime (identity);
 142                                 DisposeIdentity (identity);
 143                                 return true;
 144                         }
 145                 }
 146
 147                 public static Type GetServerTypeForUri (string uri)
 148                 {
 149                         Identity ident = GetIdentityForUri (uri);
 150                         if (ident == null) return null;
 151                         return ident.ObjectType;
 152                 }
 153
 154                 public static string GetObjectUri (MarshalByRefObject obj)
 155                 {
 156                         Identity ident = GetObjectIdentity(obj);
 157                         if (ident is ClientIdentity) return ((ClientIdentity)ident).TargetUri;
 158                         else if (ident != null) return ident.ObjectUri;
 159                         else return null;
 160                 }
 161
 162                 public static object Unmarshal (ObjRef objref)
 163                 {
 164                         return Unmarshal(objref, true);
 165                 }
 166
 167                 public static object Unmarshal (ObjRef objref, bool fRefine)
 168                 {
 169                         // FIXME: use type name when fRefine==true
 170
 171                         Type classToProxy = fRefine ? objref.ServerType : typeof (MarshalByRefObject);
 172                         if (classToProxy == null) classToProxy = typeof (MarshalByRefObject);
 173
 174                         if (objref.IsReferenceToWellKnow)
 175                                 return GetRemoteObject(objref, classToProxy);
 176                         else
 177                         {
 178                                 if (classToProxy.IsContextful)
 179                                 {
 180                                         // Look for a ProxyAttribute
 181                                         ProxyAttribute att = (ProxyAttribute) Attribute.GetCustomAttribute (classToProxy, typeof(ProxyAttribute),true);
 182                                         if (att != null)
 183                                                 return att.CreateProxy (objref, classToProxy, null, null).GetTransparentProxy();
 184                                 }
 185                                 return GetProxyForRemoteObject (objref, classToProxy);
 186                         }
 187                 }
 188
 189                 public static ObjRef Marshal (MarshalByRefObject obj)
 190                 {
 191                         return Marshal (obj, null, null);
 192                 }
 193
 194                 public static ObjRef Marshal (MarshalByRefObject obj, string uri)
 195                 {
 196                         return Marshal (obj, uri, null);
 197                 }
 198
 199                 public static ObjRef Marshal (MarshalByRefObject obj, string uri, Type requested_type)
 200                 {
 201                         if (IsTransparentProxy (obj))
 202                         {
 203                                 RealProxy proxy = RemotingServices.GetRealProxy(obj);
 204                                 Identity identity = proxy.ObjectIdentity;
 205
 206                                 if (identity != null)
 207                                 {
 208                                         if (identity.ObjectType.IsContextful && !identity.IsConnected)
 209                                         {
 210                                                 // Unregistered local contextbound object. Register now.
 211                                                 ClientActivatedIdentity cboundIdentity = (ClientActivatedIdentity)identity;
 212                                                 if (uri == null) uri = NewUri();
 213                                                 cboundIdentity.ObjectUri = uri;
 214                                                 RegisterServerIdentity (cboundIdentity);
 215                                                 cboundIdentity.StartTrackingLifetime ((ILease)obj.InitializeLifetimeService());
 216                                                 return cboundIdentity.CreateObjRef(requested_type);
 217                                         }
 218                                         else if (uri != null)
 219                                                 throw new RemotingException ("It is not possible marshal a proxy of a remote object");
 220
 221                                         return proxy.ObjectIdentity.CreateObjRef(requested_type);
 222                                 }
 223                         }
 224
 225                         if (requested_type == null) requested_type = obj.GetType();
 226
 227                         if (uri == null)
 228                         {
 229                                 uri = NewUri();
 230                                 CreateClientActivatedServerIdentity (obj, requested_type, uri);
 231                         }
 232                         else
 233                         {
 234                                 ClientActivatedIdentity identity = GetIdentityForUri ("/" + uri) as ClientActivatedIdentity;
 235                                 if (identity == null || obj != identity.GetServerObject())
 236                                         CreateClientActivatedServerIdentity (obj, requested_type, uri);
 237                         }
 238
 239                         return obj.CreateObjRef(requested_type);
 240                 }
 241
 242                 static string NewUri ()
 243                 {
 244                         int n = Interlocked.Increment (ref next_id);
 245                         return app_id + Environment.TickCount + "_" + n;
 246                 }
 247
 248                 public static RealProxy GetRealProxy (object proxy)
 249                 {
 250                         if (!IsTransparentProxy(proxy)) throw new RemotingException("Cannot get the real proxy from an object that is not a transparent proxy");
 251                         return (RealProxy)((TransparentProxy)proxy)._rp;
 252                 }
 253
 254                 public static MethodBase GetMethodBaseFromMethodMessage(IMethodMessage msg)
 255                 {
 256                         Type type = Type.GetType (msg.TypeName);
 257                         if (type == null)
 258                                 throw new RemotingException ("Type '" + msg.TypeName + "' not found!");
 259
 260                         BindingFlags bflags = BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic;
 261                         if (msg.MethodSignature == null)
 262                                 return type.GetMethod (msg.MethodName, bflags);
 263                         else
 264                                 return type.GetMethod (msg.MethodName, bflags, null, (Type[]) msg.MethodSignature, null);
 265                 }
 266
 267                 public static void GetObjectData(object obj, SerializationInfo info, StreamingContext context)
 268                 {
 269                         if (obj == null) throw new ArgumentNullException ("obj");
 270
 271                         ObjRef oref = Marshal ((MarshalByRefObject)obj);
 272                         oref.GetObjectData (info, context);
 273                 }
 274
 275                 public static ObjRef GetObjRefForProxy(MarshalByRefObject obj)
 276                 {
 277                         Identity ident = GetObjectIdentity(obj);
 278                         if (ident == null) return null;
 279                         else return ident.CreateObjRef(null);
 280                 }
 281
 282                 public static object GetLifetimeService (MarshalByRefObject obj)
 283                 {
 284                         if (obj == null) return null;
 285                         return obj.GetLifetimeService ();
 286                 }
 287
 288                 public static IMessageSink GetEnvoyChainForProxy (MarshalByRefObject obj)
 289                 {
 290                         if (IsTransparentProxy(obj))
 291                                 return ((ClientIdentity)GetRealProxy (obj).ObjectIdentity).EnvoySink;
 292                         else
 293                                 throw new ArgumentException ("obj must be a proxy","obj");
 294                 }
 295
 296                 public static void LogRemotingStage (int stage)
 297                 {
 298                         throw new NotImplementedException ();
 299                 }
 300
 301                 [MonoTODO]
 302                 public static string GetSessionIdForMethodMessage(IMethodMessage msg)
 303                 {
 304                         throw new NotImplementedException ();
 305                 }
 306
 307                 public static bool IsMethodOverloaded(IMethodMessage msg)
 308                 {
 309                         Type type = msg.MethodBase.DeclaringType;
 310                         MemberInfo[] members = type.GetMember (msg.MethodName, MemberTypes.Method, BindingFlags.NonPublic | BindingFlags.Public | BindingFlags.Instance);
 311                         return members.Length > 1;
 312                 }
 313
 314                 public static bool IsObjectOutOfAppDomain(object tp)
 315                 {
 316                         Identity ident = GetObjectIdentity((MarshalByRefObject)tp);
 317                         if (ident != null) return !ident.IsFromThisAppDomain;
 318                         else return false;
 319                 }
 320
 321                 public static bool IsObjectOutOfContext(object tp)
 322                 {
 323                         ServerIdentity ident = GetObjectIdentity((MarshalByRefObject)tp) as ServerIdentity;
 324                         if (ident != null) return ident.Context != System.Threading.Thread.CurrentContext;
 325                         else return false;
 326                 }
 327
 328                 public static bool IsOneWay(MethodBase method)
 329                 {
 330                         // TODO: use internal call for better performance
 331                         object[] atts = method.GetCustomAttributes (typeof (OneWayAttribute), false);
 332                         return atts.Length > 0;
 333                 }
 334
 335                 public static bool IsAsyncMessage(IMessage msg)
 336                 {
 337                         if (! (msg is MonoMethodMessage)) return false;
 338                         else if (((MonoMethodMessage)msg).IsAsync) return true;
 339                         else if (IsOneWay (((MonoMethodMessage)msg).MethodBase)) return true;
 340                         else return false;
 341                 }
 342
 343                 public static void SetObjectUriForMarshal(MarshalByRefObject obj, string uri)
 344                 {
 345                         if (IsTransparentProxy (obj)) throw new RemotingException ("SetObjectUriForMarshal method should only be called for MarshalByRefObjects that exist in the current AppDomain.");
 346                         Marshal (obj, uri);
 347                 }
 348
 349                 #region Internal Methods
 350
 351                 internal static object CreateClientProxy (ActivatedClientTypeEntry entry, object[] activationAttributes)
 352                 {
 353                         if (entry.ContextAttributes != null || activationAttributes != null)
 354                         {
 355                                 ArrayList props = new ArrayList ();
 356                                 if (entry.ContextAttributes != null) props.AddRange (entry.ContextAttributes);
 357                                 if (activationAttributes != null) props.AddRange (activationAttributes);
 358                                 return CreateClientProxy (entry.ObjectType, entry.ApplicationUrl, props.ToArray ());
 359                         }
 360                         else
 361                                 return CreateClientProxy (entry.ObjectType, entry.ApplicationUrl, null);
 362                 }
 363
 364                 internal static object CreateClientProxy (Type objectType, string url, object[] activationAttributes)
 365                 {
 366                         string activationUrl = url + "/RemoteActivationService.rem";
 367
 368                         string objectUri;
 369                         IMessageSink sink = GetClientChannelSinkChain (activationUrl, null, out objectUri);
 370
 371                         RemotingProxy proxy = new RemotingProxy (objectType, activationUrl, activationAttributes);
 372                         return proxy.GetTransparentProxy();
 373                 }
 374
 375                 internal static object CreateClientProxy (WellKnownClientTypeEntry entry)
 376                 {
 377                         return Connect (entry.ObjectType, entry.ObjectUrl, null);
 378                 }
 379
 380                 internal static object CreateClientProxyForContextBound (Type type, object[] activationAttributes)
 381                 {
 382                         if (type.IsContextful)
 383                         {
 384                                 // Look for a ProxyAttribute
 385                                 ProxyAttribute att = (ProxyAttribute) Attribute.GetCustomAttribute (type, typeof(ProxyAttribute), true);
 386                                 if (att != null)
 387                                         return att.CreateInstance (type);
 388                         }
 389                         RemotingProxy proxy = new RemotingProxy (type, ChannelServices.CrossContextUrl, activationAttributes);
 390                         return proxy.GetTransparentProxy();
 391                 }
 392
 393                 internal static Identity GetIdentityForUri (string uri)
 394                 {
 395                         lock (uri_hash)
 396                         {
 397                                 return (Identity)uri_hash [GetNormalizedUri(uri)];
 398                         }
 399                 }
 400
 401                 internal static Identity GetObjectIdentity (MarshalByRefObject obj)
 402                 {
 403                         if (IsTransparentProxy(obj))
 404                                 return GetRealProxy (obj).ObjectIdentity;
 405                         else
 406                                 return obj.ObjectIdentity;
 407                 }
 408
 409                 internal static ClientIdentity GetOrCreateClientIdentity(ObjRef objRef, Type proxyType, out object clientProxy)
 410                 {
 411                         // This method looks for an identity for the given url.
 412                         // If an identity is not found, it creates the identity and
 413                         // assigns it a proxy to the remote object.
 414
 415                         // Creates the client sink chain for the given url or channelData.
 416                         // It will also get the object uri from the url.
 417
 418                         object channelData = objRef.ChannelInfo != null ? objRef.ChannelInfo.ChannelData : null;
 419                         string url = (channelData == null) ? objRef.URI : null;
 420
 421                         string objectUri;
 422                         IMessageSink sink = GetClientChannelSinkChain (url, channelData, out objectUri);
 423
 424                         if (objectUri == null) objectUri = objRef.URI;
 425
 426                         lock (uri_hash)
 427                         {
 428                                 clientProxy = null;
 429                                 string uri = GetNormalizedUri (objRef.URI);
 430
 431                                 ClientIdentity identity = uri_hash [uri] as ClientIdentity;
 432                                 if (identity != null)
 433                                 {
 434                                         // Object already registered
 435                                         clientProxy = identity.ClientProxy;
 436                                         if (clientProxy != null) return identity;
 437
 438                                         // The proxy has just been GCed, so its identity cannot
 439                                         // be reused. Just dispose it.
 440                                         DisposeIdentity (identity);
 441                                 }
 442
 443                                 // Creates an identity and a proxy for the remote object
 444
 445                                 identity = new ClientIdentity (objectUri, objRef);
 446                                 identity.ChannelSink = sink;
 447
 448                                 // Registers the identity
 449                                 uri_hash [uri] = identity;
 450
 451                                 if (proxyType != null)
 452                                 {
 453                                         RemotingProxy proxy = new RemotingProxy (proxyType, identity);
 454                                         clientProxy = proxy.GetTransparentProxy();
 455                                         identity.ClientProxy = (MarshalByRefObject) clientProxy;
 456                                 }
 457
 458                                 return identity;
 459                         }
 460                 }
 461
 462                 static IMessageSink GetClientChannelSinkChain(string url, object channelData, out string objectUri)
 463                 {
 464                         IMessageSink sink = ChannelServices.CreateClientChannelSinkChain (url, channelData, out objectUri);
 465                         if (sink == null)
 466                         {
 467                                 if (url != null)
 468                                 {
 469                                         string msg = String.Format ("Cannot create channel sink to connect to URL {0}. An appropriate channel has probably not been registered.", url);
 470                                         throw new RemotingException (msg);
 471                                 }
 472                                 else
 473                                 {
 474                                         string msg = String.Format ("Cannot create channel sink to connect to the remote object. An appropriate channel has probably not been registered.", url);
 475                                         throw new RemotingException (msg);
 476                                 }
 477                         }
 478                         return sink;
 479                 }
 480
 481                 internal static ClientActivatedIdentity CreateContextBoundObjectIdentity(Type objectType)
 482                 {
 483                         ClientActivatedIdentity identity = new ClientActivatedIdentity (null, objectType);
 484                         identity.ChannelSink = ChannelServices.CrossContextChannel;
 485                         return identity;
 486                 }
 487
 488                 internal static ClientActivatedIdentity CreateClientActivatedServerIdentity(MarshalByRefObject realObject, Type objectType, string objectUri)
 489                 {
 490                         ClientActivatedIdentity identity = new ClientActivatedIdentity (objectUri, objectType);
 491                         identity.AttachServerObject (realObject, Context.DefaultContext);
 492                         RegisterServerIdentity (identity);
 493                         identity.StartTrackingLifetime ((ILease)realObject.InitializeLifetimeService ());
 494                         return identity;
 495                 }
 496
 497                 internal static ServerIdentity CreateWellKnownServerIdentity(Type objectType, string objectUri, WellKnownObjectMode mode)
 498                 {
 499                         ServerIdentity identity;
 500
 501                         if (mode == WellKnownObjectMode.SingleCall)
 502                                 identity = new  SingleCallIdentity(objectUri, Context.DefaultContext, objectType);
 503                         else
 504                                 identity = new  SingletonIdentity(objectUri, Context.DefaultContext, objectType);
 505
 506                         RegisterServerIdentity (identity);
 507                         return identity;
 508                 }
 509
 510                 private static void RegisterServerIdentity(ServerIdentity identity)
 511                 {
 512                         lock (uri_hash)
 513                         {
 514                                 if (uri_hash.ContainsKey (identity.ObjectUri))
 515                                         throw new RemotingException ("Uri already in use: " + identity.ObjectUri);
 516
 517                                 uri_hash[identity.ObjectUri] = identity;
 518                         }
 519                 }
 520
 521                 internal static object GetProxyForRemoteObject (ObjRef objref, Type classToProxy)
 522                 {
 523                         ClientActivatedIdentity identity = GetIdentityForUri (objref.URI) as ClientActivatedIdentity;
 524                         if (identity != null) return identity.GetServerObject ();
 525                         else return GetRemoteObject (objref, classToProxy);
 526                 }
 527
 528                 internal static object GetRemoteObject(ObjRef objRef, Type proxyType)
 529                 {
 530                         object proxy;
 531                         GetOrCreateClientIdentity (objRef, proxyType, out proxy);
 532                         return proxy;
 533                 }
 534
 535                 internal static object GetDomainProxy(AppDomain domain)
 536                 {
 537                         byte[] data = null;
 538
 539                         Context currentContext = Thread.CurrentContext;
 540                         AppDomain currentDomain = AppDomain.InternalSetDomain (domain);
 541                         try
 542                         {
 543                                 data = domain.GetMarshalledDomainObjRef ();
 544                         }
 545                         finally
 546                         {
 547                                 AppDomain.InternalSetDomain (currentDomain);
 548                                 AppDomain.InternalSetContext (currentContext);
 549                         }
 550
 551                         MemoryStream stream = new MemoryStream (data);
 552                         ObjRef appref = (ObjRef) CADSerializer.DeserializeObject (stream);
 553                         return (AppDomain) RemotingServices.Unmarshal(appref);
 554                 }
 555
 556                 private static void RegisterInternalChannels()
 557                 {
 558                         CrossAppDomainChannel.RegisterCrossAppDomainChannel();
 559                 }
 560
 561                 internal static void DisposeIdentity (Identity ident)
 562                 {
 563                         lock (uri_hash)
 564                         {
 565                                 if (!ident.Disposed) {
 566                                         uri_hash.Remove (ident.ObjectUri);
 567                                         ident.Disposed = true;
 568                                 }
 569                         }
 570                 }
 571
 572                 internal static Identity GetMessageTargetIdentity (IMessage msg)
 573                 {
 574                         // Returns the identity where the message is sent
 575
 576                         if (msg is IInternalMessage)
 577                                 return ((IInternalMessage)msg).TargetIdentity;
 578
 579                         lock (uri_hash)
 580                         {
 581                                 string uri = GetNormalizedUri (((IMethodMessage)msg).Uri);
 582                                 return uri_hash [uri] as ServerIdentity;
 583                         }
 584                 }
 585
 586                 internal static void SetMessageTargetIdentity (IMessage msg, Identity ident)
 587                 {
 588                         if (msg is IInternalMessage)
 589                                 ((IInternalMessage)msg).TargetIdentity = ident;
 590                 }
 591
 592                 internal static bool UpdateOutArgObject (ParameterInfo pi, object local, object remote)
 593                 {
 594                         if (local is StringBuilder)
 595                         {
 596                                 StringBuilder sb = local as StringBuilder;
 597                                 sb.Remove (0, sb.Length);
 598                                 sb.Append (remote.ToString());
 599                                 return true;
 600                         }
 601                         else if (pi.ParameterType.IsArray && ((Array)local).Rank == 1)
 602                         {
 603                                 Array alocal = (Array) local;
 604                                 if (alocal.Rank == 1)
 605                                 {
 606                                         Array.Copy ((Array) remote, alocal, alocal.Length);
 607                                         return true;
 608                                 }
 609                                 else
 610                                 {
 611                                         // TODO
 612                                 }
 613                         }
 614                         return false;
 615                 }
 616
 617                 static string GetNormalizedUri (string uri)
 618                 {
 619                         if (uri.StartsWith ("/")) return uri.Substring (1);
 620                         else return uri;
 621                 }
 622
 623                 #endregion
 624         }
 625 }