Consolidate role availability checking code

dbutils.c

@@ -1858,51 +1858,6 @@ can_execute_pg_promote(PGconn *conn)
 }
 
 
-bool
-connection_has_pg_settings(PGconn *conn)
-{
-	bool		has_pg_settings = false;
-
-	/* superusers can always read pg_settings */
-	if (is_superuser_connection(conn, NULL) == true)
-	{
-		has_pg_settings = true;
-	}
-	/* from PostgreSQL 10, a non-superuser may have been granted access */
-	else if (PQserverVersion(conn) >= 100000)
-	{
-		PQExpBufferData query;
-		PGresult   *res;
-
-		initPQExpBuffer(&query);
-		appendPQExpBufferStr(&query,
-							 "  SELECT CASE "
-							 "           WHEN pg_catalog.pg_has_role('pg_monitor','MEMBER') "
-							 "             THEN TRUE "
-							 "           WHEN pg_catalog.pg_has_role('pg_read_all_settings','MEMBER') "
-							 "             THEN TRUE "
-							 "           ELSE FALSE "
-							 "         END AS has_pg_settings");
-
-		res = PQexec(conn, query.data);
-
-		if (PQresultStatus(res) != PGRES_TUPLES_OK)
-		{
-			log_db_error(conn, query.data,
-						 _("connection_has_pg_settings(): unable to query user roles"));
-		}
-		else
-		{
-			has_pg_settings = atobool(PQgetvalue(res, 0, 0));
-		}
-		termPQExpBuffer(&query);
-		PQclear(res);
-	}
-
-	return has_pg_settings;
-}
-
-
 /*
  * Determine if the user associated with the current connection is
  * a member of the "pg_monitor" default role, or optionally one

dbutils.h

@@ -453,7 +453,6 @@ TimeLineHistoryEntry *get_timeline_history(PGconn *repl_conn, TimeLineID tli);
 
 /* user/role information functions */
 bool		can_execute_pg_promote(PGconn *conn);
-bool		connection_has_pg_settings(PGconn *conn);
 bool		connection_has_pg_monitor_role(PGconn *conn, const char *subrole);
 bool		is_replication_role(PGconn *conn, char *rolname);
 bool		is_superuser_connection(PGconn *conn, t_connection_user *userinfo);

repmgr-action-node.c

@@ -2045,7 +2045,7 @@ do_node_check_data_directory(PGconn *conn, OutputMode mode, t_node_info *node_in
 	 * Check actual data directory matches that in repmgr.conf; note this requires
 	 * a superuser connection
 	 */
-	if (connection_has_pg_settings(conn) == true)
+	if (connection_has_pg_monitor_role(conn, "pg_read_all_settings") == true)
 	{
 		/* we expect to have a database connection */
 		if (get_pg_setting(conn, "data_directory", actual_data_directory) == false)

repmgr-action-standby.c

@@ -5784,7 +5784,7 @@ check_source_server()
 		 * This will check if the user is superuser or (from Pg10) is a member
 		 * of "pg_read_all_settings"/"pg_monitor"
 		 */
-		if (connection_has_pg_settings(source_conn))
+		if (connection_has_pg_monitor_role(source_conn, "pg_read_all_settings") == true)
 		{
 			SettingsUser = REPMGR_USER;
 		}