class/Mono.Cecil/Mono.Cecil.Metadata/GuidHeap.cs

   1 //
   2 // GuidHeap.cs
   3 //
   4 // Author:
   5 //   Jb Evain (jbevain@gmail.com)
   6 //
   7 // (C) 2005 Jb Evain
   8 //
   9 // Permission is hereby granted, free of charge, to any person obtaining
  10 // a copy of this software and associated documentation files (the
  11 // "Software"), to deal in the Software without restriction, including
  12 // without limitation the rights to use, copy, modify, merge, publish,
  13 // distribute, sublicense, and/or sell copies of the Software, and to
  14 // permit persons to whom the Software is furnished to do so, subject to
  15 // the following conditions:
  16 //
  17 // The above copyright notice and this permission notice shall be
  18 // included in all copies or substantial portions of the Software.
  19 //
  20 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  21 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  22 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  23 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  24 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  25 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  26 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  27 //
  28
  29 namespace Mono.Cecil.Metadata {
  30
  31         using System;
  32         using System.Collections;
  33
  34         public class GuidHeap : MetadataHeap {
  35
  36                 readonly IDictionary m_guids;
  37
  38                 public IDictionary Guids {
  39                         get { return m_guids; }
  40                 }
  41
  42                 public GuidHeap (MetadataStream stream) : base (stream, MetadataStream.GUID)
  43                 {
  44                         int capacity = (int)(stream.Header.Size / 16);
  45                         m_guids = new Hashtable (capacity);
  46                 }
  47
  48                 public Guid this [uint index] {
  49                         get {
  50                                 if (index == 0)
  51                                         return new Guid (new byte [16]);
  52
  53                                 int idx = (int) index - 1;
  54
  55                                 if (m_guids.Contains (idx))
  56                                         return (Guid) m_guids [idx];
  57
  58                                 if (idx + 16 > this.Data.Length)
  59                                         throw new IndexOutOfRangeException ();
  60
  61                                 byte [] buffer = null;
  62                                 if (this.Data.Length == 16) {
  63                                         buffer = this.Data;
  64                                 } else {
  65                                         buffer = new byte [16];
  66                                         Buffer.BlockCopy (this.Data, idx, buffer, 0, 16);
  67                                 }
  68                                 Guid res = new Guid (buffer);
  69                                 m_guids [idx] = res;
  70                                 return res;
  71                         }
  72                         set { m_guids [index] = value; }
  73                 }
  74
  75                 public override void Accept (IMetadataVisitor visitor)
  76                 {
  77                         visitor.VisitGuidHeap (this);
  78                 }
  79         }
  80 }