source: branches/RemoveBackwardsCompatibility/HeuristicLab.ExtLibs/HeuristicLab.Cecil/0.9.5/Mono.Cecil-0.9.5/Mono.Cecil/Mono.Cecil.Metadata/Buffers.cs

//
// TableHeapBuffer.cs
//
// Author:
//   Jb Evain (jbevain@gmail.com)
//
// Copyright (c) 2008 - 2011 Jb Evain
//
// 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;
using System.Collections.Generic;
using System.Text;

using Mono.Cecil.PE;

using RVA = System.UInt32;

#if !READ_ONLY

namespace Mono.Cecil.Metadata {

  sealed class TableHeapBuffer : HeapBuffer {

    readonly ModuleDefinition module;
    readonly MetadataBuilder metadata;

    internal MetadataTable [] tables = new MetadataTable [45];

    bool large_string;
    bool large_blob;
    readonly int [] coded_index_sizes = new int [13];
    readonly Func<Table, int> counter;

    public override bool IsEmpty {
      get { return false; }
    }

    public TableHeapBuffer (ModuleDefinition module, MetadataBuilder metadata)
      : base (24)
    {
      this.module = module;
      this.metadata = metadata;
      this.counter = GetTableLength;
    }

    int GetTableLength (Table table)
    {
      var md_table = tables [(int) table];
      return md_table != null ? md_table.Length : 0;
    }

    public TTable GetTable<TTable> (Table table) where TTable : MetadataTable, new ()
    {
      var md_table = (TTable) tables [(int) table];
      if (md_table != null)
        return md_table;

      md_table = new TTable ();
      tables [(int) table] = md_table;
      return md_table;
    }

    public void WriteBySize (uint value, int size)
    {
      if (size == 4)
        WriteUInt32 (value);
      else
        WriteUInt16 ((ushort) value);
    }

    public void WriteBySize (uint value, bool large)
    {
      if (large)
        WriteUInt32 (value);
      else
        WriteUInt16 ((ushort) value);
    }

    public void WriteString (uint @string)
    {
      WriteBySize (@string, large_string);
    }

    public void WriteBlob (uint blob)
    {
      WriteBySize (blob, large_blob);
    }

    public void WriteRID (uint rid, Table table)
    {
      var md_table = tables [(int) table];
      WriteBySize (rid, md_table == null ? false : md_table.IsLarge);
    }

    int GetCodedIndexSize (CodedIndex coded_index)
    {
      var index = (int) coded_index;
      var size = coded_index_sizes [index];
      if (size != 0)
        return size;

      return coded_index_sizes [index] = coded_index.GetSize (counter);
    }

    public void WriteCodedRID (uint rid, CodedIndex coded_index)
    {
      WriteBySize (rid, GetCodedIndexSize (coded_index));
    }

    public void WriteTableHeap ()
    {
      WriteUInt32 (0);          // Reserved
      WriteByte (GetTableHeapVersion ()); // MajorVersion
      WriteByte (0);            // MinorVersion
      WriteByte (GetHeapSizes ());    // HeapSizes
      WriteByte (10);           // Reserved2
      WriteUInt64 (GetValid ());      // Valid
      WriteUInt64 (0x0016003301fa00);   // Sorted

      WriteRowCount ();
      WriteTables ();
    }

    void WriteRowCount ()
    {
      for (int i = 0; i < tables.Length; i++) {
        var table = tables [i];
        if (table == null || table.Length == 0)
          continue;

        WriteUInt32 ((uint) table.Length);
      }
    }

    void WriteTables ()
    {
      for (int i = 0; i < tables.Length; i++) {
        var table = tables [i];
        if (table == null || table.Length == 0)
          continue;

        table.Write (this);
      }
    }

    ulong GetValid ()
    {
      ulong valid = 0;

      for (int i = 0; i < tables.Length; i++) {
        var table = tables [i];
        if (table == null || table.Length == 0)
          continue;

        table.Sort ();
        valid |= (1UL << i);
      }

      return valid;
    }

    byte GetHeapSizes ()
    {
      byte heap_sizes = 0;

      if (metadata.string_heap.IsLarge) {
        large_string = true;
        heap_sizes |= 0x01;
      }

      if (metadata.blob_heap.IsLarge) {
        large_blob = true;
        heap_sizes |= 0x04;
      }

      return heap_sizes;
    }

    byte GetTableHeapVersion ()
    {
      switch (module.Runtime) {
      case TargetRuntime.Net_1_0:
      case TargetRuntime.Net_1_1:
        return 1;
      default:
        return 2;
      }
    }

    public void FixupData (RVA data_rva)
    {
      var table = GetTable<FieldRVATable> (Table.FieldRVA);
      if (table.length == 0)
        return;

      var field_idx_size = GetTable<FieldTable> (Table.Field).IsLarge ? 4 : 2;
      var previous = this.position;

      base.position = table.position;
      for (int i = 0; i < table.length; i++) {
        var rva = ReadUInt32 ();
        base.position -= 4;
        WriteUInt32 (rva + data_rva);
        base.position += field_idx_size;
      }

      base.position = previous;
    }
  }

  sealed class ResourceBuffer : ByteBuffer {

    public ResourceBuffer ()
      : base (0)
    {
    }

    public uint AddResource (byte [] resource)
    {
      var offset = (uint) this.position;
      WriteInt32 (resource.Length);
      WriteBytes (resource);
      return offset;
    }
  }

  sealed class DataBuffer : ByteBuffer {

    public DataBuffer ()
      : base (0)
    {
    }

    public RVA AddData (byte [] data)
    {
      var rva = (RVA) position;
      WriteBytes (data);
      return rva;
    }
  }

  abstract class HeapBuffer : ByteBuffer {

    public bool IsLarge {
      get { return base.length > 65535; }
    }

    public abstract bool IsEmpty { get; }

    protected HeapBuffer (int length)
      : base (length)
    {
    }
  }

  class StringHeapBuffer : HeapBuffer {

    readonly Dictionary<string, uint> strings = new Dictionary<string, uint> ();

    public sealed override bool IsEmpty {
      get { return length <= 1; }
    }

    public StringHeapBuffer ()
      : base (1)
    {
      WriteByte (0);
    }

    public uint GetStringIndex (string @string)
    {
      uint index;
      if (strings.TryGetValue (@string, out index))
        return index;

      index = (uint) base.position;
      WriteString (@string);
      strings.Add (@string, index);
      return index;
    }

    protected virtual void WriteString (string @string)
    {
      WriteBytes (Encoding.UTF8.GetBytes (@string));
      WriteByte (0);
    }
  }

  sealed class BlobHeapBuffer : HeapBuffer {

    readonly Dictionary<ByteBuffer, uint> blobs = new Dictionary<ByteBuffer, uint> (new ByteBufferEqualityComparer ());

    public override bool IsEmpty {
      get { return length <= 1; }
    }

    public BlobHeapBuffer ()
      : base (1)
    {
      WriteByte (0);
    }

    public uint GetBlobIndex (ByteBuffer blob)
    {
      uint index;
      if (blobs.TryGetValue (blob, out index))
        return index;

      index = (uint) base.position;
      WriteBlob (blob);
      blobs.Add (blob, index);
      return index;
    }

    void WriteBlob (ByteBuffer blob)
    {
      WriteCompressedUInt32 ((uint) blob.length);
      WriteBytes (blob);
    }
  }

  sealed class UserStringHeapBuffer : StringHeapBuffer {

    protected override void WriteString (string @string)
    {
      WriteCompressedUInt32 ((uint) @string.Length * 2 + 1);

      byte special = 0;

      for (int i = 0; i < @string.Length; i++) {
        var @char = @string [i];
        WriteUInt16 (@char);

        if (special == 1)
          continue;

        if (@char < 0x20 || @char > 0x7e) {
          if (@char > 0x7e
            || (@char >= 0x01 && @char <= 0x08)
            || (@char >= 0x0e && @char <= 0x1f)
            || @char == 0x27
            || @char == 0x2d) {

            special = 1;
          }
        }
      }

      WriteByte (special);
    }
  }
}

#endif