[PATCH] Improve the security of opcontrol

[William C. <wc...@re...>]

Hi Maynard,

Thanks for reviewing I have revised the patches in PR3303383 "Improve the security of opcontrol". I have revised:

0002-Do-additional-checks-on-user-supplied-arguments.patch

There is a test to make sure there argument is  non-empty for error_if_invalid_arg.
Revised the code for --save to give a more understandable error messages.

If the patch is okay I will commit it.

-Will