class/Mono.Cecil/Mono.Cecil.Metadata/StringsHeap.cs

   1 //
   2 // StringsHeap.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.Collections;
  32         using System.Text;
  33
  34         public class StringsHeap : MetadataHeap {
  35
  36                 IDictionary m_strings;
  37
  38                 public string this [uint index] {
  39                         get {
  40                                 string str = m_strings [index] as string;
  41                                 if (str == null) {
  42                                         str = ReadStringAt (index);
  43                                         m_strings [index] = str;
  44                                 }
  45                                 return str;
  46                         }
  47                         set { m_strings [index] = value; }
  48                 }
  49
  50                 internal StringsHeap (MetadataStream stream) : base (stream, MetadataStream.Strings)
  51                 {
  52                         m_strings = new Hashtable ();
  53                 }
  54
  55                 string ReadStringAt (uint index)
  56                 {
  57                         byte [] data = this.Data;
  58                         int heap_length = data.Length;
  59
  60                         if (index > heap_length - 1)
  61                                 return string.Empty;
  62
  63                         int length = 0;
  64                         for (int i = (int) index; i < heap_length; i++) {
  65                                 if (data [i] == 0)
  66                                         break;
  67
  68                                 length++;
  69                         }
  70
  71                         return Encoding.UTF8.GetString (data, (int) index, length);
  72                 }
  73
  74                 public override void Accept (IMetadataVisitor visitor)
  75                 {
  76                         visitor.VisitStringsHeap (this);
  77                 }
  78         }
  79 }