Thanks very much, Levente. I'll dig into your suggestions tomorrow. I made my first contact over ham radio tonight after another generous soul totally hooked me up with cables and power supplies and programmed my radio. I am so excited! Now on the air, KO4PYS.
--- Kindly, Robert
On 6/3/21 8:43 PM, Levente Uzonyi wrote:
Hi Robert,
I see the following potential causes:
In #findErrorLocationsDegree:coefficients:count:fieldSize:result: the return value in ambiguous. You make the primitive fail if not enough errors are found. But after the send, you don't check for failure but simply send #methodReturnReceiver. Instead, you should either check for primitive failure after the send or make #findErrorLocationsDegree:coefficients:count:fieldSize:result: return boolean value: the method was successful or not. E.g. when numErrors = 1, return true, in the other branch, return e = numErrors. (If slang doesn't support boolean types, just use 0 and 1). In the actual primitive method, check for the value returned by that method and fail the primitive when needed. Once the primitive has failed, you ought to return from it. I see the above pattern in other methods too (marking the primitive as failed in a not-top-level method without checking for failure outside). Those need to be fixed as well.
Another potential issue I see is that the validation of the arguments is not complete. E.g.: #stackIntegerValue: may have already set the primitive to failed if the argument was not an integer. So, before continuing, that has to be checked.
Another possible but unlikely problem is that you assume that both result and coefficients have at least one field. But that may not be true which can result in segfaults.
Levente
cryptography@lists.squeakfoundation.org