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 (RemotingServices.IsTransparentProxy (realTarget)) {
  78                                                 // The call to IsInstanceOfType will force the proxy
  79                                                 // to load the real type of the remote object. This is
  80                                                 // needed to make sure that subsequent calls to
  81                                                 // GetType() return the expected type.
  82                                                 Assembly tasm = Assembly.Load (targetTypeAssembly);
  83                                                 Type tt = tasm.GetType (targetTypeName);
  84                                                 if (!tt.IsInstanceOfType (realTarget))
  85                                                         throw new RemotingException ("Unexpected proxy type.");
  86                                         }
  87                                         del = Delegate.CreateDelegate (dt, realTarget, methodName);
  88                                 }
  89                                 else {
  90                                         Assembly tasm = Assembly.Load (targetTypeAssembly);
  91                                         Type tt = tasm.GetType (targetTypeName);
  92                                         del = Delegate.CreateDelegate (dt, tt, methodName);
  93                                 }
  94
  95                                 if (!del.Method.IsPublic)
  96                                         throw new SerializationException (Locale.GetText (
  97                                                 "Serialization will not deserialize delegates to non-public methods."));
  98
  99                                 return del;
 100                         }
 101                 }
 102
 103                 DelegateSerializationHolder(SerializationInfo info, StreamingContext ctx)
 104                 {
 105                         DelegateEntry entryChain = (DelegateEntry)info.GetValue ("Delegate", typeof(DelegateEntry));
 106
 107                         // Count the number of delegates to combine
 108                         int count = 0;
 109                         DelegateEntry entry = entryChain;
 110                         while (entry != null) {
 111                                 entry = entry.delegateEntry;
 112                                 count++;
 113                         }
 114
 115                         // Deserializes and combines the delegates
 116                         if (count == 1)
 117                                 _delegate = entryChain.DeserializeDelegate (info);
 118                         else
 119                         {
 120                                 Delegate[] delegates = new Delegate[count];
 121                                 entry = entryChain;
 122                                 for (int n=0; n<count; n++)
 123                                 {
 124                                         delegates[n] = entry.DeserializeDelegate (info);
 125                                         entry = entry.delegateEntry;
 126                                 }
 127                                 _delegate = Delegate.Combine (delegates);
 128                         }
 129                 }
 130
 131                 public static void GetDelegateData (Delegate instance, SerializationInfo info, StreamingContext ctx)
 132                 {
 133                         // Fills a SerializationInfo object with the information of the delegate.
 134
 135                         Delegate[] delegates = instance.GetInvocationList ();
 136                         DelegateEntry lastEntry = null;
 137                         for (int n=0; n<delegates.Length; n++) {
 138                                 Delegate del = delegates[n];
 139                                 string targetLabel = (del.Target != null) ? ("target" + n) : null;
 140                                 DelegateEntry entry = new DelegateEntry (del, targetLabel);
 141
 142                                 if (lastEntry == null)
 143                                         info.AddValue ("Delegate", entry);
 144                                 else
 145                                         lastEntry.delegateEntry = entry;
 146
 147                                 lastEntry = entry;
 148                                 if (del.Target != null)
 149                                         info.AddValue (targetLabel, del.Target);
 150                         }
 151                         info.SetType (typeof (DelegateSerializationHolder));
 152                 }
 153
 154                 public void GetObjectData (SerializationInfo info, StreamingContext context)
 155                 {
 156                         // Not needed.
 157                         throw new NotSupportedException ();
 158                 }
 159
 160                 public object GetRealObject (StreamingContext context)
 161                 {
 162                         return _delegate;
 163                 }
 164         }
 165 }