From b3b9281253563cf4bc80a495c8401e7c15a5c958 Mon Sep 17 00:00:00 2001
From: Ian Barwick <ian@2ndquadrant.com>
Date: Tue, 6 Oct 2020 18:00:11 +0900
Subject: [PATCH] Parse pg_basebackup option --waldir/--xlogdir

---
 configfile.c            | 32 +++++++++++++++++++++++++-------
 configfile.h            |  3 ++-
 repmgr-action-standby.c |  4 ++++
 3 files changed, 31 insertions(+), 8 deletions(-)

diff --git a/configfile.c b/configfile.c
index 62439a57..08cb2e0b 100644
--- a/configfile.c
+++ b/configfile.c
@@ -2056,17 +2056,12 @@ bool
 parse_pg_basebackup_options(const char *pg_basebackup_options, t_basebackup_options *backup_options, int server_version_num, ItemList *error_list)
 {
 	bool		backup_options_ok = true;
-
 	int			c = 0,
 				argc_item = 0;
-
 	char	  **argv_array = NULL;
-
 	int			optindex = 0;
-
 	struct option *long_options = NULL;
 
-
 	/*
 	 * We're only interested in these options.
 	 */
@@ -2075,7 +2070,8 @@ parse_pg_basebackup_options(const char *pg_basebackup_options, t_basebackup_opti
 	{
 		{"slot", required_argument, NULL, 'S'},
 		{"wal-method", required_argument, NULL, 'X'},
-		{"no-slot", no_argument, NULL, 1},
+		{"waldir", required_argument, NULL, 1},
+		{"no-slot", no_argument, NULL, 2},
 		{NULL, 0, NULL, 0}
 	};
 
@@ -2086,6 +2082,7 @@ parse_pg_basebackup_options(const char *pg_basebackup_options, t_basebackup_opti
 	{
 		{"slot", required_argument, NULL, 'S'},
 		{"xlog-method", required_argument, NULL, 'X'},
+		{"xlogdir", required_argument, NULL, 1},
 		{NULL, 0, NULL, 0}
 	};
 
@@ -2119,10 +2116,13 @@ parse_pg_basebackup_options(const char *pg_basebackup_options, t_basebackup_opti
 				strncpy(backup_options->wal_method, optarg, MAXLEN);
 				break;
 			case 1:
+				strncpy(backup_options->waldir, optarg, MAXPGPATH);
+				break;
+			case 2:
 				backup_options->no_slot = true;
 				break;
 			case '?':
-				if (server_version_num >= 100000 && optopt == 1)
+				if (server_version_num >= 100000 && optopt == 2)
 				{
 					if (error_list != NULL)
 					{
@@ -2143,6 +2143,24 @@ parse_pg_basebackup_options(const char *pg_basebackup_options, t_basebackup_opti
 		backup_options_ok = false;
 	}
 
+	/*
+	 * If --waldir/--xlogdir provided, check it's an absolute path.
+	 */
+	if (backup_options->waldir[0] != '\0')
+	{
+		canonicalize_path(backup_options->waldir);
+		if (!is_absolute_path(backup_options->waldir))
+		{
+			if (error_list != NULL)
+			{
+				item_list_append_format(error_list,
+										"--%s must be provided with an absolute path",
+										server_version_num >= 100000 ? "waldir" : "xlogdir");
+			}
+			backup_options_ok = false;
+		}
+	}
+
 	free_parsed_argv(&argv_array);
 
 	return backup_options_ok;
diff --git a/configfile.h b/configfile.h
index da2ae106..5769fb63 100644
--- a/configfile.h
+++ b/configfile.h
@@ -262,10 +262,11 @@ typedef struct
 {
 	char		slot[MAXLEN];
 	char		wal_method[MAXLEN];
+	char		waldir[MAXPGPATH];
 	bool		no_slot;		/* from PostgreSQL 10 */
 } t_basebackup_options;
 
-#define T_BASEBACKUP_OPTIONS_INITIALIZER { "", "", false }
+#define T_BASEBACKUP_OPTIONS_INITIALIZER { "", "", "", false }
 
 
 typedef enum
diff --git a/repmgr-action-standby.c b/repmgr-action-standby.c
index 2828145f..19bef47e 100644
--- a/repmgr-action-standby.c
+++ b/repmgr-action-standby.c
@@ -7203,6 +7203,10 @@ run_file_backup(t_node_info *local_node_record)
 				if (vers[i] < 0 && source_server_version_num >= abs(vers[i]))
 					continue;
 
+				/*
+				 * If --waldir/--xlogdir specified in "pg_basebackup_options",
+				 * create a symlink rather than make a directory.
+				 */
 				maxlen_snprintf(filename, "%s/%s", local_data_directory, dirs[i]);
 				if (mkdir(filename, S_IRWXU) != 0 && errno != EEXIST)
 				{