signedness and long vs int corrections

Change-Id: I67c6b9e05b16f5d8d4693879f1656db50dc7ec48
Reviewed-on: https://gerrit.libreoffice.org/29355Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Jochen Nitschke <j.nitschke+logerrit@ok.de>