-SPECFILE="$1"
-SPECFILE="${SPECFILE%%/*}"
-SPECFILE="$(basename $SPECFILE .spec)"
-SPEC="$SPECFILE/$SPECFILE.spec"
+SPEC=$(basename "$1" .spec).spec
+PACKAGE=$(basename "$SPEC" .spec)
+TOPDIR=$(rpm -E %_topdir)
+PACKAGEDIR=$TOPDIR/$PACKAGE
+SPECFILE="$TOPDIR/$PACKAGE/$SPEC"