CompressedStack.cs :  » 2.6.4-mono-.net-core » System.Threading » System » Threading » C# / CSharp Open Source

//
// System.Threading.Thread.cs
//
// Authors:
//  Zoltan Varga (vargaz@freemail.hu)
//  Sebastien Pouliot  <sebastien@ximian.com>
//
// Copyright (C) 2004-2005 Novell, Inc (http://www.novell.com)
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
// 
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//

using System.Collections;
using System.Diagnostics;
using System.Reflection;
using System.Runtime.InteropServices;
using System.Runtime.Serialization;
using System.Security;
using System.Security.Permissions;

namespace System.Threading{

  [Serializable]
  public sealed class CompressedStack : ISerializable {
    private ArrayList _list;

    internal CompressedStack (int length)
    {
      if (length > 0)
        _list = new ArrayList (length);
    }

    internal CompressedStack (CompressedStack cs)
    {
      if ((cs != null) && (cs._list != null))
        _list = (ArrayList) cs._list.Clone ();
    }

    [ComVisibleAttribute (false)]
    public CompressedStack CreateCopy ()
    {
      return new CompressedStack (this);
    }

    public static CompressedStack Capture ()
    {
      CompressedStack cs = new CompressedStack (0);
      cs._list = SecurityFrame.GetStack (1);

      // include any current CompressedStack inside the new Capture
      CompressedStack currentCs = Thread.CurrentThread.GetCompressedStack ();
      if (currentCs != null) {
        for (int i=0; i < currentCs._list.Count; i++)
          cs._list.Add (currentCs._list [i]);
      }
      return cs;
    }

    // NOTE: This method doesn't show in the class library status page because
    // it cannot be "found" with the StrongNameIdentityPermission for ECMA key.
    // But it's there!
    [SecurityPermission (SecurityAction.LinkDemand, UnmanagedCode = true)]
    [StrongNameIdentityPermission (SecurityAction.LinkDemand, PublicKey="00000000000000000400000000000000")]
    static public CompressedStack GetCompressedStack ()
    {
      // Note: CompressedStack.GetCompressedStack doesn't return null
      // like Thread.CurrentThread.GetCompressedStack if no compressed
      // stack is present.
      CompressedStack cs = Thread.CurrentThread.GetCompressedStack ();
      if (cs == null) {
        cs = CompressedStack.Capture ();
      } else {
        // merge the existing compressed stack (from a previous Thread) with the current
        // Thread stack so we can assign "all of it" to yet another Thread
        CompressedStack newstack = CompressedStack.Capture ();
        for (int i=0; i < newstack._list.Count; i++)
          cs._list.Add (newstack._list [i]);
      }
      return cs;
    }

    [MonoTODO ("incomplete")]
    [ReflectionPermission (SecurityAction.Demand, MemberAccess = true)]
    public void GetObjectData (SerializationInfo info, StreamingContext context)
    {
      if (info == null)
        throw new ArgumentNullException ("info");
    }

    [SecurityPermission (SecurityAction.LinkDemand, Infrastructure = true)]
    static public void Run (CompressedStack compressedStack, ContextCallback callback, object state)
    {
      if (compressedStack == null)
        throw new ArgumentException ("compressedStack");

      Thread t = Thread.CurrentThread;
      CompressedStack original = null;
      try {
        original = t.GetCompressedStack (); 
        t.SetCompressedStack (compressedStack);
        callback (state);
      }
      finally {
        if (original != null)
          t.SetCompressedStack (original);
      }
    }

    // internal stuff
    internal bool Equals (CompressedStack cs)
    {
      if (IsEmpty ())
        return cs.IsEmpty ();
      if (cs.IsEmpty ())
        return false;
      if (_list.Count != cs._list.Count)
        return false;

      for (int i=0; i < _list.Count; i++) {
        SecurityFrame sf1 = (SecurityFrame) _list [i];
        SecurityFrame sf2 = (SecurityFrame) cs._list [i];
        if (!sf1.Equals (sf2))
          return false;
      }
      return true;
    }

    internal bool IsEmpty ()
    {
      return ((_list == null) || (_list.Count == 0));
    }

    internal IList List {
      get { return _list; }
    }
  }
}