softflowd/debian/softflowd.preinst

#!/bin/sh

set -e

DEFAULT_CONF='/etc/softflowd/default.conf'
LEGACY_CONF='/etc/default/softflowd'

case "$1" in
install)
    ;;
upgrade)
    if \
        dpkg --compare-versions "$2" lt 0.9.9-4~ &&
        [ -f "$LEGACY_CONF" ] &&
        [ ! -f "$DEFAULT_CONF" ]
    then
        # create /etc/softflowd/default.conf from /etc/default/softflowd
        # lower-case key names
        mkdir -p "$(dirname "$DEFAULT_CONF")"
        sed  -e '
            s/^INTERFACE=/interface=/ ;
            s/^OPTIONS=/options=/ ;
        ' <"$LEGACY_CONF" >"$DEFAULT_CONF"
    fi
    ;;
abort-upgrade)
    ;;
*)
    echo "preinst called with unknown argument '$1'"
    exit 1
    ;;
esac

#DEBHELPER#
exit 0