/// <summary>
/// Removes top three stack items and converts them to <see cref="long"/>s: value, Min, Max.
/// Pushes 1 if value was in range, otherwise 0.
/// Return value indicates success.
/// </summary>
/// <param name="opData">Data to use</param>
/// <param name="error">Error message (null if sucessful, otherwise will contain information about the failure)</param>
/// <returns>True if operation was successful, false if otherwise</returns>
public override bool Run(IOpData opData, out string error)
{
if (opData.ItemCount < 3)
{
error = "Invalid number of elements in stack.";
return(false);
}
// Stack is: x then min then max so we pop max first
if (!OpHelper.TryConvertByteArrayToInt(opData.Pop(), out long max, true))
{
error = "Couldn't convert to number.";
return(false);
}
if (!OpHelper.TryConvertByteArrayToInt(opData.Pop(), out long min, true))
{
error = "Couldn't convert to number.";
return(false);
}
if (!OpHelper.TryConvertByteArrayToInt(opData.Pop(), out long x, true))
{
error = "Couldn't convert to number.";
return(false);
}
int c = (x >= min && x < max) ? 1 : 0;
opData.Push(OpHelper.IntToByteArray(c));
error = null;
return(true);
}
protected bool TrySetLockTime(IOpData opData, out string error)
{
if (opData.ItemCount < 1)
{
error = "Not enough items left in the stack.";
return(false);
}
// The two locktime OPs (CheckLocktimeVerify and CheckSequenceVerify) used to be NOPs. NOPs don't do anything.
// For backward compatibility of the softfork, Run Peeks at the top item of the stack instead of Poping it.
byte[] data = opData.Peek();
// TODO: move this check to OpHelper
// (for locktimes max length is 5 for others it is 4)
if (data.Length > 5)
{
error = "Data length for locktimes can not be bigger than 5.";
return(false);
}
if (!OpHelper.TryConvertByteArrayToInt(data, out lt, true))
{
error = "Invalid number format.";
return(false);
}
if (lt < 0)
{
error = "Locktime can not be negative.";
return(false);
}
error = null;
return(true);
}
protected bool TrySetValue(IOpData opData, out string error)
{
if (opData.ItemCount < 1)
{
error = "Not enough items left in the stack.";
return(false);
}
if (!OpHelper.TryConvertByteArrayToInt(opData.Pop(), out a, true))
{
error = "Invalid number format.";
return(false);
}
error = null;
return(true);
}
/// <summary>
/// Copies the nth item from top of the stack to the top. Return value indicates success.
/// </summary>
/// <param name="opData">Data to use</param>
/// <param name="error">Error message (null if sucessful, otherwise will contain information about the failure)</param>
/// <returns>True if operation was successful, false if otherwise</returns>
public override bool Run(IOpData opData, out string error)
{
if (opData.ItemCount < 2) // At least 2 items is needed. 1 telling us the index and the other to copy
{
error = "There was not enough items left in the stack to copy to top.";
return(false);
}
byte[] data = opData.Pop();
if (data.Length > 4) // Initial test to reject any huge numbers
{
error = "'n' is too big.";
return(false);
}
if (!OpHelper.TryConvertByteArrayToInt(data, out long n, true)) // TODO: set isStrict field base don BIP62
{
error = "Invalid number format.";
return(false);
}
if (n < 0)
{
error = "'n' can not be negative.";
return(false);
}
if (opData.ItemCount <= n) // 'n' is index so it can't be equal to ItemCount
{
error = "There was not enough items left in the stack to copy to top.";
return(false);
}
opData.Push(opData.PeekAtIndex((int)n));
error = null;
return(true);
}
