Extended mariadb-test-run to define MARIADB_TOPDIR and MARIADB_DATADIR

This is for preparing MariaDB for catalogs.

mtr tests should in the future use MARIADB_TOPDIR or MARIADB_DATADIR
instead of '@@datadir'. This is especially true for replication tests
that access binlog files.

MARIADB_TOPDIR is the top directory where binary log and engine log files
resides.
MARIADB_DATADIR is the directory where the database/schema directories
resides.

MARIADB_TOPDIR is not depending on catalogs.
When catalogs is used MARIADB_DATADIR will point to the directory of the
current catalog. If catalogs is not used then
MARIAD_DATADIR=MARIADB_TOPDIR.

mysql-test/mariadb-test-run.pl

@@ -268,6 +268,9 @@ our $opt_force= 0;
 our $opt_skip_not_found= 0;
 our $opt_mem= $ENV{'MTR_MEM'};
 our $opt_clean_vardir= $ENV{'MTR_CLEAN_VARDIR'};
+our $opt_catalogs= 0;
+our $opt_catalog_name="";
+our $catalog_name="def";
 
 our $opt_gcov;
 our $opt_gprof;
@@ -3945,6 +3948,23 @@ sub run_testcase ($$) {
       }
     }
 
+    # Set up things for catalogs
+    # The values of MARIADB_TOPDIR and MARIAD_DATADIR should
+    # be taken from the values used by the default (first)
+    # connection that is used by mariadb-test.
+    my ($mysqld, @servers);
+    @servers= all_servers();
+    $mysqld= $servers[0];
+    $ENV{'MARIADB_TOPDIR'}= $mysqld->value('datadir');
+    if (!$opt_catalogs)
+    {
+      $ENV{'MARIADB_DATADIR'}= $mysqld->value('datadir');
+    }
+    else
+    {
+      $ENV{'MARIADB_DATADIR'}= $mysqld->value('datadir') . "/" . $catalog_name;
+    }
+
     # Write start of testcase to log
     mark_log($path_current_testlog, $tinfo);