Control character check

[tomspiderlabs]

Added a check to search for control characters and return -1 (in "err") if found.

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[hallyn]

Thank you for the patch. But let's not do two runs through the characters. You can just combine this with the check below for isprint().

If you'd rather I make that change in-line while merging, please let me know.

[tomspiderlabs]

Added a control character check within the non-printable character pass.

[ikerexxe]

Two minor comments and I'd like to raise that one of the tests is failing in the CI. I didn't check it profoundly, but it's a usermod test case and you are changing that file so it seems valid.

[tomspiderlabs]

Updates to the text make sense as per the changes made to control characters returning -1 and non-printables returning 1 still.

[ikerexxe]

@hallyn what do we do with the failing test case?

[hallyn]

@hallyn what do we do with the failing test case?

I'll have to look into it this hopefully tonight, else this weekend. I'll look at the others you mentioned too.

[hallyn]

Oh - I see, it fails in your doc-only pr too. Let's just merge then.