MDEV-17236 mariabackup incorrectly tries to open ibdata1

Thirunarayanan · Thirunarayanan · commit 7e4bbd3aa65e · 2018-09-20T17:13:12.000+05:30
if custom undo tablespace is defined

- In case of multiple undo tablespace, mariabackup have to open system
tablespace to find the list of undo tablespace present in TRX_SYS page.
For opening system tablespace, mariabackup should fetch the file name
from already initialized system tablespace object.
diff --git a/extra/mariabackup/xtrabackup.cc b/extra/mariabackup/xtrabackup.cc
@@ -3255,7 +3255,7 @@ static dberr_t xb_assign_undo_space_start()
 	}
 
 	snprintf(name + dirnamelen, (sizeof name) - dirnamelen,
-		 "%s", "ibdata1");
+		 "%s", srv_sys_space.first_datafile()->name());
 
 	file = os_file_create(0, name, OS_FILE_OPEN,
 			      OS_FILE_NORMAL, OS_DATA_FILE, true, &ret);
diff --git a/mysql-test/suite/mariabackup/undo_space_id.opt b/mysql-test/suite/mariabackup/undo_space_id.opt
@@ -1,2 +1,3 @@
 --debug=d,innodb_undo_upgrade
+--innodb_data_file_path=ib_mysql:10M
 --innodb_undo_tablespaces=2

Original file line number	Diff line number	Diff line change
`@@ -3255,7 +3255,7 @@ static dberr_t xb_assign_undo_space_start()`
`3255`	`3255`	`}`
`3256`	`3256`
`3257`	`3257`	`snprintf(name + dirnamelen, (sizeof name) - dirnamelen,`
`3258`		`- "%s", "ibdata1");`
	`3258`	`+ "%s", srv_sys_space.first_datafile()->name());`
`3259`	`3259`
`3260`	`3260`	`file = os_file_create(0, name, OS_FILE_OPEN,`
`3261`	`3261`	`OS_FILE_NORMAL, OS_DATA_FILE, true, &ret);`
Original file line number	Diff line number	Diff line change
`@@ -1,2 +1,3 @@`
`1`	`1`	`--debug=d,innodb_undo_upgrade`
	`2`	`+--innodb_data_file_path=ib_mysql:10M`
`2`	`3`	`--innodb_undo_tablespaces=2`