Catch error in packaging script and fail the build

This is to fix the regression added in #2433. In this fix
we're going to fail the build early if --use-timestamp is
provided and working directory is *not* clean. And also
fail the build if something in the script has returned
non-zero value.

Author: khos2ow

packaging/build-deb.sh

@@ -16,7 +16,7 @@
 # specific language governing permissions and limitations
 # under the License.
 
-#set -e
+set -e
 
 #
 # This script builds Debian packages for CloudStack and does
@@ -100,6 +100,17 @@ while [ -n "$1" ]; do
     esac
 done
 
+# Fail early if working directory is NOT clean and --use-timestamp was provided
+if [ "$USE_TIMESTAMP" == "true" ]; then
+    if [ -n "$(cd $PWD/../; git status -s)" ]; then
+        echo "Erro: You have uncommitted changes and asked for --use-timestamp to be used."
+        echo "      --use-timestamp flag is going to temporarily change  POM versions  and"
+        echo "      revert them at the end of build, and there's no  way we can do partial"
+        echo "      revert. Please commit your changes first or omit --use-timestamp flag."
+        exit 1
+    fi
+fi
+
 DCH=$(which dch)
 if [ -z "$DCH" ] ; then
     echo -e "dch not found, please install devscripts at first. \nDEB Build Failed"
@@ -148,4 +159,6 @@ dpkg-buildpackage -uc -us -b
 
 /bin/mv /tmp/changelog.orig debian/changelog
 
-(cd $PWD; git reset --hard)
+if [ "$USE_TIMESTAMP" == "true" ]; then
+    (cd $PWD; git reset --hard)
+fi