Novacoin/CScript.cs

   1 \feffusing System;
   2 using System.Text;
   3
   4 using System.Collections;
   5 using System.Collections.Generic;
   6
   7 namespace Novacoin
   8 {
   9     public class CScriptException : Exception
  10     {
  11         public CScriptException()
  12         {
  13         }
  14
  15         public CScriptException(string message)
  16             : base(message)
  17         {
  18         }
  19
  20         public CScriptException(string message, Exception inner)
  21             : base(message, inner)
  22         {
  23         }
  24     }
  25
  26     /// <summary>
  27     /// Representation of script code
  28     /// </summary>
  29         public class CScript
  30         {
  31         private List<byte> codeBytes;
  32
  33         /// <summary>
  34         /// Initializes an empty instance of CScript
  35         /// </summary>
  36                 public CScript ()
  37                 {
  38             codeBytes = new List<byte>();
  39                 }
  40
  41         /// <summary>
  42         /// Initializes new instance of CScript and fills it with supplied bytes
  43         /// </summary>
  44         /// <param name="bytes">List of bytes</param>
  45         public CScript(IList<byte> bytes)
  46         {
  47             codeBytes = new List<byte>(bytes);
  48         }
  49
  50         /// <summary>
  51         /// Initializes new instance of CScript and fills it with supplied bytes
  52         /// </summary>
  53         /// <param name="bytes">Array of bytes</param>
  54         public CScript(byte[] bytes)
  55         {
  56             codeBytes = new List<byte>(bytes);
  57         }
  58
  59         /// <summary>
  60         /// Adds specified operation to opcode bytes list
  61         /// </summary>
  62         /// <param name="opcode"></param>
  63         public void AddOp(opcodetype opcode)
  64         {
  65             if (opcode < opcodetype.OP_0 || opcode > opcodetype.OP_INVALIDOPCODE)
  66             {
  67                 throw new CScriptException("CScript::AddOp() : invalid opcode");
  68             }
  69
  70             codeBytes.Add((byte)opcode);
  71         }
  72
  73         /// <summary>
  74         /// Adds hash to opcode bytes list.
  75         ///    New items are added in this format:
  76         ///    hash_length_byte hash_bytes
  77         /// </summary>
  78         /// <param name="hash">Hash160 instance</param>
  79         public void AddHash(Hash160 hash)
  80         {
  81             codeBytes.Add((byte)hash.hashSize);
  82             codeBytes.AddRange(hash.hashBytes);
  83         }
  84
  85         /// <summary>
  86         /// Adds hash to opcode bytes list.
  87         ///    New items are added in this format:
  88         ///    hash_length_byte hash_bytes
  89         /// </summary>
  90         /// <param name="hash">Hash256 instance</param>
  91         public void AddHash(Hash256 hash)
  92         {
  93             codeBytes.Add((byte)hash.hashSize);
  94             codeBytes.AddRange(hash.hashBytes);
  95         }
  96
  97         public void PushData(IList<byte> dataBytes)
  98         {
  99             if (dataBytes.Count < (int)opcodetype.OP_PUSHDATA1)
 100             {
 101                 codeBytes.Add((byte)dataBytes.Count);
 102             }
 103             else if (dataBytes.Count < 0xff)
 104             {
 105                 codeBytes.Add((byte)opcodetype.OP_PUSHDATA1);
 106                 codeBytes.Add((byte)dataBytes.Count);
 107             }
 108             else if (dataBytes.Count < 0xffff)
 109             {
 110                 codeBytes.Add((byte)opcodetype.OP_PUSHDATA2);
 111
 112                 byte[] szBytes = BitConverter.GetBytes((short)dataBytes.Count);
 113                 if (BitConverter.IsLittleEndian)
 114                     Array.Reverse(szBytes);
 115
 116                 codeBytes.AddRange(szBytes);
 117             }
 118             else if ((uint)dataBytes.Count < 0xffffffff)
 119             {
 120                 codeBytes.Add((byte)opcodetype.OP_PUSHDATA2);
 121
 122                 byte[] szBytes = BitConverter.GetBytes((uint)dataBytes.Count);
 123                 if (BitConverter.IsLittleEndian)
 124                     Array.Reverse(szBytes);
 125
 126                 codeBytes.AddRange(szBytes);
 127             }
 128             codeBytes.AddRange(dataBytes);
 129         }
 130
 131         /// <summary>
 132         /// Disassemble current script code
 133         /// </summary>
 134         /// <returns>Code listing</returns>
 135                 public override string ToString()
 136                 {
 137                         StringBuilder sb = new StringBuilder();
 138
 139             WrappedList<byte> wCodeBytes = new WrappedList<byte>(codeBytes);
 140
 141             while (wCodeBytes.ItemsLeft > 0)
 142             {
 143                 if (sb.Length != 0)
 144                 {
 145                     sb.Append(" ");
 146                 }
 147
 148                 opcodetype opcode;
 149                 IEnumerable<byte> pushArgs;
 150                 if (!ScriptOpcode.GetOp(ref wCodeBytes, out opcode, out pushArgs))
 151                 {
 152                     sb.Append("[error]");
 153                     break;
 154                 }
 155
 156                 if (0 <= opcode && opcode <= opcodetype.OP_PUSHDATA4)
 157                 {
 158                     sb.Append(ScriptOpcode.ValueString(pushArgs));
 159                 }
 160                 else
 161                 {
 162                     sb.Append(ScriptOpcode.GetOpName(opcode));
 163                 }
 164             }
 165
 166             return sb.ToString();
 167                 }
 168         }
 169 }
 170