class/corlib/System.Threading/CompressedStack.cs

   1 //
   2 // System.Threading.Thread.cs
   3 //
   4 // Authors:
   5 //      Zoltan Varga (vargaz@freemail.hu)
   6 //      Sebastien Pouliot  <sebastien@ximian.com>
   7 //
   8 // Copyright (C) 2004-2005 Novell, Inc (http://www.novell.com)
   9 //
  10 // Permission is hereby granted, free of charge, to any person obtaining
  11 // a copy of this software and associated documentation files (the
  12 // "Software"), to deal in the Software without restriction, including
  13 // without limitation the rights to use, copy, modify, merge, publish,
  14 // distribute, sublicense, and/or sell copies of the Software, and to
  15 // permit persons to whom the Software is furnished to do so, subject to
  16 // the following conditions:
  17 //
  18 // The above copyright notice and this permission notice shall be
  19 // included in all copies or substantial portions of the Software.
  20 //
  21 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  22 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  23 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  24 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  25 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  26 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  27 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  28 //
  29
  30 using System.Collections;
  31 using System.Diagnostics;
  32 using System.Reflection;
  33 using System.Runtime.InteropServices;
  34 using System.Runtime.Serialization;
  35 using System.Security;
  36 using System.Security.Permissions;
  37
  38 namespace System.Threading {
  39
  40         [Serializable]
  41         public sealed class CompressedStack : ISerializable {
  42                 private ArrayList _list;
  43
  44                 internal CompressedStack (int length)
  45                 {
  46                         if (length > 0)
  47                                 _list = new ArrayList (length);
  48                 }
  49
  50                 internal CompressedStack (CompressedStack cs)
  51                 {
  52                         if ((cs != null) && (cs._list != null))
  53                                 _list = (ArrayList) cs._list.Clone ();
  54                 }
  55
  56                 [ComVisibleAttribute (false)]
  57                 public CompressedStack CreateCopy ()
  58                 {
  59                         return new CompressedStack (this);
  60                 }
  61
  62                 public static CompressedStack Capture ()
  63                 {
  64                         CompressedStack cs = new CompressedStack (0);
  65                         cs._list = SecurityFrame.GetStack (1);
  66
  67                         // include any current CompressedStack inside the new Capture
  68                         CompressedStack currentCs = Thread.CurrentThread.GetCompressedStack ();
  69                         if (currentCs != null) {
  70                                 for (int i=0; i < currentCs._list.Count; i++)
  71                                         cs._list.Add (currentCs._list [i]);
  72                         }
  73                         return cs;
  74                 }
  75
  76                 // NOTE: This method doesn't show in the class library status page because
  77                 // it cannot be "found" with the StrongNameIdentityPermission for ECMA key.
  78                 // But it's there!
  79                 [SecurityPermission (SecurityAction.LinkDemand, UnmanagedCode = true)]
  80                 [StrongNameIdentityPermission (SecurityAction.LinkDemand, PublicKey="00000000000000000400000000000000")]
  81                 static public CompressedStack GetCompressedStack ()
  82                 {
  83                         // Note: CompressedStack.GetCompressedStack doesn't return null
  84                         // like Thread.CurrentThread.GetCompressedStack if no compressed
  85                         // stack is present.
  86                         CompressedStack cs = Thread.CurrentThread.GetCompressedStack ();
  87                         if (cs == null) {
  88                                 cs = CompressedStack.Capture ();
  89                         } else {
  90                                 // merge the existing compressed stack (from a previous Thread) with the current
  91                                 // Thread stack so we can assign "all of it" to yet another Thread
  92                                 CompressedStack newstack = CompressedStack.Capture ();
  93                                 for (int i=0; i < newstack._list.Count; i++)
  94                                         cs._list.Add (newstack._list [i]);
  95                         }
  96                         return cs;
  97                 }
  98
  99                 [MonoTODO ("incomplete")]
 100                 [ReflectionPermission (SecurityAction.Demand, MemberAccess = true)]
 101                 public void GetObjectData (SerializationInfo info, StreamingContext context)
 102                 {
 103                         if (info == null)
 104                                 throw new ArgumentNullException ("info");
 105                 }
 106
 107                 [SecurityPermission (SecurityAction.LinkDemand, Infrastructure = true)]
 108                 static public void Run (CompressedStack compressedStack, ContextCallback callback, object state)
 109                 {
 110                         if (compressedStack == null)
 111                                 throw new ArgumentException ("compressedStack");
 112
 113                         Thread t = Thread.CurrentThread;
 114                         CompressedStack original = null;
 115                         try {
 116                                 original = t.GetCompressedStack ();
 117                                 t.SetCompressedStack (compressedStack);
 118                                 callback (state);
 119                         }
 120                         finally {
 121                                 if (original != null)
 122                                         t.SetCompressedStack (original);
 123                         }
 124                 }
 125
 126                 // internal stuff
 127                 internal bool Equals (CompressedStack cs)
 128                 {
 129                         if (IsEmpty ())
 130                                 return cs.IsEmpty ();
 131                         if (cs.IsEmpty ())
 132                                 return false;
 133                         if (_list.Count != cs._list.Count)
 134                                 return false;
 135
 136                         for (int i=0; i < _list.Count; i++) {
 137                                 SecurityFrame sf1 = (SecurityFrame) _list [i];
 138                                 SecurityFrame sf2 = (SecurityFrame) cs._list [i];
 139                                 if (!sf1.Equals (sf2))
 140                                         return false;
 141                         }
 142                         return true;
 143                 }
 144
 145                 internal bool IsEmpty ()
 146                 {
 147                         return ((_list == null) || (_list.Count == 0));
 148                 }
 149
 150                 internal IList List {
 151                         get { return _list; }
 152                 }
 153         }
 154 }