public void Digest(ReadOnlySpan <byte> data, Span <byte> result, params object[] extra)
{
Contract.RequiresNonNull(extra, nameof(extra));
Contract.Requires <ArgumentException>(extra.Length > 0, $"{nameof(extra)} must not be empty");
Contract.Requires <ArgumentException>(result.Length >= 32, $"{nameof(result)} must be greater or equal 32 bytes");
// concat nTime as hex string to data
var nTime = (ulong)extra[0];
var nTimeHex = nTime.ToString("X").HexToByteArray();
Span <byte> dataEx = stackalloc byte[data.Length + nTimeHex.Length];
data.CopyTo(dataEx);
if (nTimeHex.Length > 0)
{
var dest = dataEx.Slice(data.Length);
nTimeHex.CopyTo(dest);
}
fixed(byte *input = dataEx)
{
fixed(byte *output = result)
{
LibMultihash.keccak(input, output, (uint)data.Length);
}
}
}