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
  36 namespace System
  37 {
  38         [Serializable]
  39         internal class DelegateSerializationHolder: ISerializable, IObjectReference
  40         {
  41                 Delegate _delegate; // The deserialized delegate
  42
  43                 [Serializable]
  44                 class DelegateEntry
  45                 {
  46                         string type;
  47                         string assembly;
  48                         public object target;
  49                         string targetTypeAssembly;
  50                         string targetTypeName;
  51                         string methodName;
  52                         public DelegateEntry delegateEntry; // next delegate in the invocation list
  53
  54                         // A DelegateEntry holds information about a delegate that is part
  55                         // of an invocation list of a multicast delegate.
  56                         public DelegateEntry (Delegate del, string targetLabel)
  57                         {
  58                                 type = del.GetType().FullName;
  59                                 assembly = del.GetType().Assembly.FullName;
  60                                 target = targetLabel;
  61                                 targetTypeAssembly = del.Method.DeclaringType.Assembly.FullName;
  62                                 targetTypeName = del.Method.DeclaringType.FullName;
  63                                 methodName = del.Method.Name;
  64                         }
  65
  66                         public Delegate DeserializeDelegate (SerializationInfo info)
  67                         {
  68                                 object realTarget = null;
  69                                 if (target != null)
  70                                         realTarget = info.GetValue (target.ToString(), typeof(object));
  71
  72                                 Assembly dasm = Assembly.Load (assembly);
  73                                 Type dt = dasm.GetType (type);
  74                                 Delegate del;
  75                                 if (realTarget != null)
  76                                         del = Delegate.CreateDelegate (dt, realTarget, methodName);
  77                                 else {
  78                                         Assembly tasm = Assembly.Load (targetTypeAssembly);
  79                                         Type tt = tasm.GetType (targetTypeName);
  80                                         del = Delegate.CreateDelegate (dt, tt, methodName);
  81                                 }
  82
  83                                 if (!del.Method.IsPublic)
  84                                         throw new SerializationException (Locale.GetText (
  85                                                 "Serialization will not deserialize delegates to non-public methods."));
  86
  87                                 return del;
  88                         }
  89                 }
  90
  91                 DelegateSerializationHolder(SerializationInfo info, StreamingContext ctx)
  92                 {
  93                         DelegateEntry entryChain = (DelegateEntry)info.GetValue ("Delegate", typeof(DelegateEntry));
  94
  95                         // Count the number of delegates to combine
  96                         int count = 0;
  97                         DelegateEntry entry = entryChain;
  98                         while (entry != null) {
  99                                 entry = entry.delegateEntry;
 100                                 count++;
 101                         }
 102
 103                         // Deserializes and combines the delegates
 104                         if (count == 1)
 105                                 _delegate = entryChain.DeserializeDelegate (info);
 106                         else
 107                         {
 108                                 Delegate[] delegates = new Delegate[count];
 109                                 entry = entryChain;
 110                                 for (int n=0; n<count; n++)
 111                                 {
 112                                         delegates[n] = entry.DeserializeDelegate (info);
 113                                         entry = entry.delegateEntry;
 114                                 }
 115                                 _delegate = Delegate.Combine (delegates);
 116                         }
 117                 }
 118
 119                 public static void GetDelegateData (Delegate instance, SerializationInfo info, StreamingContext ctx)
 120                 {
 121                         // Fills a SerializationInfo object with the information of the delegate.
 122
 123                         Delegate[] delegates = instance.GetInvocationList ();
 124                         DelegateEntry lastEntry = null;
 125                         for (int n=0; n<delegates.Length; n++) {
 126                                 Delegate del = delegates[n];
 127                                 string targetLabel = (del.Target != null) ? ("target" + n) : null;
 128                                 DelegateEntry entry = new DelegateEntry (del, targetLabel);
 129
 130                                 if (lastEntry == null)
 131                                         info.AddValue ("Delegate", entry);
 132                                 else
 133                                         lastEntry.delegateEntry = entry;
 134
 135                                 lastEntry = entry;
 136                                 if (del.Target != null)
 137                                         info.AddValue (targetLabel, del.Target);
 138                         }
 139                         info.SetType (typeof (DelegateSerializationHolder));
 140                 }
 141
 142                 public void GetObjectData (SerializationInfo info, StreamingContext context)
 143                 {
 144                         // Not needed.
 145                         throw new NotSupportedException ();
 146                 }
 147
 148                 public object GetRealObject (StreamingContext context)
 149                 {
 150                         return _delegate;
 151                 }
 152         }
 153 }