Add function get_data_directory()

Consolidate duplicate code

dbutils.c

@@ -293,6 +293,35 @@ get_cluster_size(PGconn *conn)
 	return size;
 }
 
+
+bool
+get_data_directory(PGconn *conn, char *data_directory)
+{
+	char		sqlquery[QUERY_STR_LEN];
+	PGresult   *res;
+
+	sqlquery_snprintf(sqlquery,
+					  "SELECT setting "
+					  " FROM pg_settings WHERE name = 'data_directory'");
+
+	log_debug(_("get_data_directory(): %s\n"), sqlquery);
+
+	res = PQexec(conn, sqlquery);
+	if (res == NULL || PQresultStatus(res) != PGRES_TUPLES_OK || PQntuples(res) != 1)
+	{
+		log_err(_("get_data_directory() - PQexec failed: %s"),
+				PQerrorMessage(conn));
+		return false;
+	}
+
+	strncpy(data_directory, PQgetvalue(res, 0, 0), MAXLEN);
+	log_debug(_("get_data_directory(): returned value is '%s'\n"), data_directory);
+	PQclear(res);
+
+	return true;
+}
+
+
 /*
  * get a connection to master by reading repl_nodes, creating a connection
  * to each node (one at a time) and finding if it is a master or a standby

dbutils.h

@@ -30,14 +30,17 @@ PGconn *establish_db_connection_by_params(const char *keywords[],
 int			is_standby(PGconn *conn);
 int			is_witness(PGconn *conn, char *schema, char *cluster, int node_id);
 bool		is_pgup(PGconn *conn, int timeout);
-int         get_server_version(PGconn *conn, char *server_version);
-int guc_set(PGconn *conn, const char *parameter, const char *op,
-		const char *value);
-int guc_set_typed(PGconn *conn, const char *parameter, const char *op,
+int			get_server_version(PGconn *conn, char *server_version);
+const char *get_cluster_size(PGconn *conn);
+bool		get_data_directory(PGconn *conn, char *data_directory);
+
+int			guc_set(PGconn *conn, const char *parameter, const char *op,
+			const char *value);
+int			guc_set_typed(PGconn *conn, const char *parameter, const char *op,
 			  const char *value, const char *datatype);
 
-const char *get_cluster_size(PGconn *conn);
-PGconn *get_master_connection(PGconn *standby_conn, char *schema, char *cluster,
+
+PGconn	   *get_master_connection(PGconn *standby_conn, char *schema, char *cluster,
 					  int *master_id, char *master_conninfo_out);
 
 int			wait_connection_availability(PGconn *conn, long long timeout);

repmgr.c

@@ -1171,8 +1171,6 @@ static void
 do_standby_promote(void)
 {
 	PGconn	   *conn;
-	PGresult   *res;
-	char		sqlquery[QUERY_STR_LEN];
 
 	char		script[MAXLEN];
 
@@ -1187,6 +1185,7 @@ do_standby_promote(void)
 				promote_check_timeout  = 60,
 				promote_check_interval = 2;
 	bool		promote_sucess = false;
+	bool        res;
 
 	/* We need to connect to check configuration */
 	log_info(_("%s connecting to standby database\n"), progname);
@@ -1221,22 +1220,15 @@ do_standby_promote(void)
 
 	log_notice(_("%s: Promoting standby\n"), progname);
 
-	/* Get the data directory full path and the last subdirectory */
-	sqlquery_snprintf(sqlquery, "SELECT setting "
-					  " FROM pg_settings WHERE name = 'data_directory'");
-	log_debug(_("standby promote: %s\n"), sqlquery);
-	res = PQexec(conn, sqlquery);
-	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+	/* Get the data directory */
+	res = get_data_directory(conn, data_dir);
+	PQfinish(conn);
+
+	if (res == false)
 	{
-		log_err(_("Can't get info about data directory: %s\n"),
-				PQerrorMessage(conn));
-		PQclear(res);
-		PQfinish(conn);
+		log_err(_("Unable to determine data directory\n"));
 		exit(ERR_BAD_CONFIG);
 	}
-	strcpy(data_dir, PQgetvalue(res, 0, 0));
-	PQclear(res);
-	PQfinish(conn);
 
 	/*
 	 * Promote standby to master.
@@ -1245,10 +1237,10 @@ do_standby_promote(void)
 	 * can't be sure when or if the promotion completes.
 	 * For now we'll poll the server until the default timeout (60 seconds)
 	 */
-	log_notice(_("%s: promoting server using %s/pg_ctl\n"), progname,
-			   options.pg_bindir);
 	maxlen_snprintf(script, "%s/pg_ctl -D %s promote",
 					options.pg_bindir, data_dir);
+	log_notice(_("%s: promoting server using '%s'\n"), progname,
+			   script);
 
 	r = system(script);
 	if (r != 0)
@@ -1294,8 +1286,7 @@ static void
 do_standby_follow(void)
 {
 	PGconn	   *conn;
-	PGresult   *res;
-	char		sqlquery[QUERY_STR_LEN];
+
 	char		script[MAXLEN];
 	char		master_conninfo[MAXLEN];
 	PGconn	   *master_conn;
@@ -1311,6 +1302,8 @@ do_standby_follow(void)
 	char		standby_version[MAXVERSIONSTR];
 	int			standby_version_num = 0;
 
+	bool        res;
+
 
 	/* We need to connect to check configuration */
 	log_info(_("%s connecting to standby database\n"), progname);
@@ -1401,21 +1394,14 @@ do_standby_follow(void)
 	log_info(_("%s Changing standby's master\n"), progname);
 
 	/* Get the data directory full path */
-	sqlquery_snprintf(sqlquery, "SELECT setting "
-					  " FROM pg_settings WHERE name = 'data_directory'");
-	log_debug(_("standby follow: %s\n"), sqlquery);
-	res = PQexec(conn, sqlquery);
-	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+	res = get_data_directory(conn, data_dir);
+	PQfinish(conn);
+
+	if (res == false)
 	{
-		log_err(_("Can't get info about data directory: %s\n"),
-				PQerrorMessage(conn));
-		PQclear(res);
-		PQfinish(conn);
+		log_err(_("Unable to determine data directory\n"));
 		exit(ERR_BAD_CONFIG);
 	}
-	strcpy(data_dir, PQgetvalue(res, 0, 0));
-	PQclear(res);
-	PQfinish(conn);
 
 	/* write the recovery.conf file */
 	if (!create_recovery_file(data_dir))
@@ -1424,10 +1410,14 @@ do_standby_follow(void)
 	/* Finally, restart the service */
 	maxlen_snprintf(script, "%s/pg_ctl %s -w -D %s -m fast restart",
 					options.pg_bindir, options.pgctl_options, data_dir);
+
+	log_notice(_("%s: restarting server using '%s'\n"), progname,
+			   script);
+
 	r = system(script);
 	if (r != 0)
 	{
-		log_err(_("Can't restart service\n"));
+		log_err(_("Can't restart server\n"));
 		exit(ERR_NO_RESTART);
 	}