mcs/class/corlib/System/DelegateSerializationHolder.cs

   1 //
   2 // System.DelegateSerializationHolder.cs
   3 //
   4 // Author:
   5 //   Lluis Sanchez Gual (lsg@ctv.es)
   6 //
   7 // (C) 2003 Lluis Sanchez Gual
   8 //
   9
  10 //
  11 // Copyright (C) 2004 Novell, Inc (http://www.novell.com)
  12 //
  13 // Permission is hereby granted, free of charge, to any person obtaining
  14 // a copy of this software and associated documentation files (the
  15 // "Software"), to deal in the Software without restriction, including
  16 // without limitation the rights to use, copy, modify, merge, publish,
  17 // distribute, sublicense, and/or sell copies of the Software, and to
  18 // permit persons to whom the Software is furnished to do so, subject to
  19 // the following conditions:
  20 //
  21 // The above copyright notice and this permission notice shall be
  22 // included in all copies or substantial portions of the Software.
  23 //
  24 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  28 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  29 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  30 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  31 //
  32
  33 using System.Reflection;
  34 using System.Runtime.Serialization;
  35 using System.Runtime.Remoting;
  36
  37 namespace System
  38 {
  39         [Serializable]
  40         internal class DelegateSerializationHolder: ISerializable, IObjectReference
  41         {
  42                 Delegate _delegate; // The deserialized delegate
  43
  44                 [Serializable]
  45                 class DelegateEntry
  46                 {
  47                         string type;
  48                         string assembly;
  49                         public object target;
  50                         string targetTypeAssembly;
  51                         string targetTypeName;
  52                         string methodName;
  53                         public DelegateEntry delegateEntry; // next delegate in the invocation list
  54
  55                         // A DelegateEntry holds information about a delegate that is part
  56                         // of an invocation list of a multicast delegate.
  57                         public DelegateEntry (Delegate del, string targetLabel)
  58                         {
  59                                 type = del.GetType().FullName;
  60                                 assembly = del.GetType().Assembly.FullName;
  61                                 target = targetLabel;
  62                                 targetTypeAssembly = del.Method.DeclaringType.Assembly.FullName;
  63                                 targetTypeName = del.Method.DeclaringType.FullName;
  64                                 methodName = del.Method.Name;
  65                         }
  66
  67                         public Delegate DeserializeDelegate (SerializationInfo info)
  68                         {
  69                                 object realTarget = null;
  70                                 if (target != null)
  71                                         realTarget = info.GetValue (target.ToString(), typeof(object));
  72
  73                                 Assembly dasm = Assembly.Load (assembly);
  74                                 Type dt = dasm.GetType (type);
  75                                 Delegate del;
  76                                 if (realTarget != null) {
  77 #if !DISABLE_REMOTING
  78                                         if (RemotingServices.IsTransparentProxy (realTarget)) {
  79                                                 // The call to IsInstanceOfType will force the proxy
  80                                                 // to load the real type of the remote object. This is
  81                                                 // needed to make sure that subsequent calls to
  82                                                 // GetType() return the expected type.
  83                                                 Assembly tasm = Assembly.Load (targetTypeAssembly);
  84                                                 Type tt = tasm.GetType (targetTypeName);
  85                                                 if (!tt.IsInstanceOfType (realTarget))
  86                                                         throw new RemotingException ("Unexpected proxy type.");
  87                                         }
  88 #endif
  89                                         del = Delegate.CreateDelegate (dt, realTarget, methodName);
  90                                 }
  91                                 else {
  92                                         Assembly tasm = Assembly.Load (targetTypeAssembly);
  93                                         Type tt = tasm.GetType (targetTypeName);
  94                                         del = Delegate.CreateDelegate (dt, tt, methodName);
  95                                 }
  96
  97                                 return del;
  98                         }
  99                 }
 100
 101                 DelegateSerializationHolder(SerializationInfo info, StreamingContext ctx)
 102                 {
 103                         DelegateEntry entryChain = (DelegateEntry)info.GetValue ("Delegate", typeof(DelegateEntry));
 104
 105                         // Count the number of delegates to combine
 106                         int count = 0;
 107                         DelegateEntry entry = entryChain;
 108                         while (entry != null) {
 109                                 entry = entry.delegateEntry;
 110                                 count++;
 111                         }
 112
 113                         // Deserializes and combines the delegates
 114                         if (count == 1)
 115                                 _delegate = entryChain.DeserializeDelegate (info);
 116                         else
 117                         {
 118                                 Delegate[] delegates = new Delegate[count];
 119                                 entry = entryChain;
 120                                 for (int n=0; n<count; n++)
 121                                 {
 122                                         delegates[n] = entry.DeserializeDelegate (info);
 123                                         entry = entry.delegateEntry;
 124                                 }
 125                                 _delegate = Delegate.Combine (delegates);
 126                         }
 127                 }
 128
 129                 public static void GetDelegateData (Delegate instance, SerializationInfo info, StreamingContext ctx)
 130                 {
 131                         // Fills a SerializationInfo object with the information of the delegate.
 132
 133                         Delegate[] delegates = instance.GetInvocationList ();
 134                         DelegateEntry lastEntry = null;
 135                         for (int n=0; n<delegates.Length; n++) {
 136                                 Delegate del = delegates[n];
 137                                 string targetLabel = (del.Target != null) ? ("target" + n) : null;
 138                                 DelegateEntry entry = new DelegateEntry (del, targetLabel);
 139
 140                                 if (lastEntry == null)
 141                                         info.AddValue ("Delegate", entry);
 142                                 else
 143                                         lastEntry.delegateEntry = entry;
 144
 145                                 lastEntry = entry;
 146                                 if (del.Target != null)
 147                                         info.AddValue (targetLabel, del.Target);
 148                         }
 149                         info.SetType (typeof (DelegateSerializationHolder));
 150                 }
 151
 152                 public void GetObjectData (SerializationInfo info, StreamingContext context)
 153                 {
 154                         // Not needed.
 155                         throw new NotSupportedException ();
 156                 }
 157
 158                 public object GetRealObject (StreamingContext context)
 159                 {
 160                         return _delegate;
 161                 }
 162         }
 163 }