Bug#491641: cheese postinst fails to check whether this is a new install

[Steve Langasek]

Package: cheese
Version: 2.22.3-2

A dist-upgrade pulled in cheese, which was not previously installed on my
system.  But when the package was installed, there was an unpleasant delay:

 Setting up cheese (2.22.3-2) ...
 Upgrade from broken Cheese version detected, running scrollkeeper-rebuilddb...

This is because the postinst fails to check for an empty value for $2:

 if [ "$1" = "configure" ] && dpkg --compare-versions "$2" lt "2.22.2-3" && \
    which scrollkeeper-rebuilddb >/dev/null 2>&1; then

This should either use lt-nl for the comparison, or explicitly check for an
empty $2 value first.

-- 
Steve Langasek                   Give me a lever long enough and a Free OS
Debian Developer                   to set it on, and I can move the world.
Ubuntu Developer                                    http://www.debian.org/
slangasek at ubuntu.com                                     vorlon at debian.org