public static void DecodeBlockHashTxIndex(byte[] bytes, out UInt256 blockHash, out int txIndex)
{
if (bytes[0] == BLOCK_TX_PREFIX)
{
blockHash = UInt256.FromByteArrayBE(bytes, 1);
txIndex = DecodeInt32(bytes, 33);
}
else
{
blockHash = UInt256.Zero;
txIndex = -1;
}
}
private void DecodeTotalWorkKey(byte[] key, out UInt256 blockHash, out BigInteger totalWork)
{
if (key.Length != 97)
{
throw new ArgumentOutOfRangeException(nameof(key));
}
else if (key[0] != TOTAL_WORK_PREFIX)
{
throw new ArgumentOutOfRangeException(nameof(key));
}
var totalWorkBytes = new byte[64];
Buffer.BlockCopy(key, 1, totalWorkBytes, 0, 64);
Array.Reverse(totalWorkBytes);
totalWork = new BigInteger(totalWorkBytes);
blockHash = UInt256.FromByteArrayBE(key, 65);
}
/// <summary>
/// Retrieves function hash from transaction data
/// </summary>
private void RetrieveFunctionHash()
{
Context.Append(UInt256.Zero); // offset for calldata
Context.Append(EvmInstruction.CALLDATALOAD);
Context.Append(UInt256.FromByteArrayBE(new byte[]
{
0, 0, 0, 1, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0
})); //hardcoded bytes used to get first 4 bytes of transaction data
Context.Append(EvmInstruction.SWAP1);
Context.Append(EvmInstruction.DIV);
Context.Append(UInt256.FromByteArrayBE(new byte[]
{
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 255, 255, 255, 255
})); //and here
Context.Append(EvmInstruction.AND);
}
public static UInt256 DecodeUInt256(byte[] value)
{
return(UInt256.FromByteArrayBE(value));
}
