Fix pidfile_is_running when $cmd is not passed

[ -z $string ] needs double quotes to handle zero-length strings
properly.

The function became a long one-liner; this patch converts it to a
version that is hopefully simpler to understand. (As a bonus, it no
longer violates the guideline for line length.)

Fixes: 09dc486 ("Handle re-used pids in pidfile_is_running")
Signed-off-by: Ihar Hrachyshka <ihrachys@redhat.com>
Signed-off-by: Numan Siddique <numans@ovn.org>
(cherry picked from commit 6e57adf)

utilities/ovn-ctl

@@ -43,8 +43,20 @@ ovn_ic_db_conf_file="$ovn_etcdir/ovn-ic-db-params.conf"
 pidfile_is_running () {
     pidfile=$1
     cmd=$2
-    test -e "$pidfile" && [ -s "$pidfile" ] && pid=`cat "$pidfile"` && pid_exists "$pid" && [ -z $cmd -o pid_comm_check "$cmd" "$pid" ]
-} >/dev/null 2>&1
+    if [ ! -s "$pidfile" ]; then
+        # file missing or empty
+        return 1
+    fi
+    pid=`cat "$pidfile"`
+    if ! pid_exists $pid; then
+        # pid is dead
+        return 1
+    fi
+    if [ -n "$cmd" ]; then
+        return $(pid_comm_check "$cmd" "$pid")
+    fi
+    return 0
+}
 
 stop_nb_ovsdb() {
     OVS_RUNDIR=${OVS_RUNDIR} stop_ovn_daemon ovnnb_db $DB_NB_PIDFILE $DB_NB_CTRL_SOCK