MDEV-32004: Cosmetic fixes

- Reviewer: <knielsen@knielsen-hq.org>
            <brandon.nesterenko@mariadb.com>

mysql-test/include/rpl_change_topology.inc

@@ -72,7 +72,7 @@
 #   include/rpl_stop_slaves.inc
 #   include/rpl_end.inc
 #
-# $rpl_server_count_length:
+# $rpl_server_count_length
 #   Set to LENGTH($rpl_server_count). So if $rpl_server_count < 10,
 #   then $rpl_server_count_length = 1; if 10 <= $rpl_server_count <
 #   100, then $rpl_server_count_length = 2, etc.
@@ -83,7 +83,7 @@
 #   server N is a slave, then the N'th number is the master of server
 #   N. If server N is not a slave, then the N'th number is just spaces
 #   (so in fact it is not a number). For example, if $rpl_topology is
-#   '1->2,2->3,3->1,2->4,5->6', then $rpl_master_list is '3122 6'.
+#   '1->2,2->3,3->1,2->4,5->6', then $rpl_master_list is '3122 5'.
 #
 # $rpl_sync_chain_dirty
 #   This variable is set to 1. This tells include/rpl_sync.inc to
@@ -124,7 +124,7 @@ if ($rpl_master_list == '')
 if ($rpl_debug)
 {
   --echo \$rpl_server_count='$rpl_server_count'
-  --echo \$rpl_server_count_length='$rpl_server_count_length'
+  --echo old \$rpl_server_count_length='$rpl_server_count_length'
   --echo new \$rpl_topology='$_rpl_topology'
   --echo old \$rpl_master_list='$rpl_master_list'
   --echo old \$rpl_sync_chain='$rpl_sync_chain'
@@ -210,6 +210,10 @@ if (!$rpl_skip_change_master)
         --let $rpl_connection_name= server_$_rpl_master
         --source include/rpl_connection.inc
         --let $_rpl_master_log_file= query_get_value(SHOW MASTER STATUS, File, 1)
+        if ($rpl_debug)
+        {
+          --echo "\$rpl_master_log_file parameter not set for the master: $_rpl_master, use the latest binlog file by executing SHOW MASTER STATUS."
+        }
       }
       # Change connection.
       --let $rpl_connection_name= server_$_rpl_server
@@ -224,6 +228,10 @@ if (!$rpl_skip_change_master)
       if (!$_rpl_master_log_pos_index)
       {
         --let $_rpl_master_log_pos=
+        if ($rpl_debug)
+        {
+          --echo "\$rpl_master_log_pos parameter not set for the master: $_rpl_master. Set log position to empty."
+        }
       }
       eval CHANGE MASTER TO MASTER_HOST = '127.0.0.1', MASTER_PORT = $_rpl_port, MASTER_USER = 'root', MASTER_LOG_FILE = '$_rpl_master_log_file'$_rpl_master_log_pos, MASTER_CONNECT_RETRY = 1;
     }

mysql-test/include/rpl_connect.inc

@@ -5,7 +5,7 @@
 # This script is normally used internally by rpl_init.inc and
 # master-slave.inc, but it can also be used in test cases that need to
 # create more connections or re-create connections after disconnect.
-#
+# Default ports SERVER_MYPORT_[1,2] are set by rpl_init.inc.
 #
 # ==== Usage ====
 #

mysql-test/include/rpl_for_each_slave.inc

@@ -1,7 +1,7 @@
 # ==== Purpose ====
 #
 # Execute a .inc file once for each server that was configured as a
-# slave by rpl_init.inc
+# slave by rpl_init.inc, for example start_slave.inc or stop_slave.inc file.
 #
 #
 # ==== Usage ====
@@ -14,6 +14,20 @@
 #   $rpl_source_file
 #     The file that will be sourced.
 #
+#   $rpl_server_count
+#     The number of servers to configure. If this is not set, the largest
+#     number in $rpl_topology will be used.
+#     This parameter is obtained from rpl_init.inc.
+#
+#   $rpl_master_list
+#     This parameter is calculated from within rpl_init.inc.
+#
+#   $rpl_server_count_length
+#     Set to LENGTH($rpl_server_count). So if $rpl_server_count < 10,
+#     then $rpl_server_count_length = 1; if 10 <= $rpl_server_count <
+#     100, then $rpl_server_count_length = 2, etc.
+#     This parameter is calculated from within rpl_change_topology.inc.
+#
 #   $rpl_debug
 #     See include/rpl_init.inc
 

mysql-test/include/rpl_init.inc

@@ -32,8 +32,9 @@
 #
 #    (It is allowed, but not required, to configure SERVER_MYPORT_1
 #    and SERVER_MYPORT_2 too. If these variables are not set, the
-#    variables MASTER_MYPORT and SLAVE_MYPORT, configured in the
-#    default my.cnf used by the rpl suite, are used instead.)
+#    variables MASTER_MYPORT and SLAVE_MYPORT are used instead.
+#    These variables are configured in the rpl_1slave_base.cnf,
+#    that is used in the default my.cnf, which is used by the rpl suite.)
 #
 # 2. Execute the following near the top of the test:
 #
@@ -193,18 +194,30 @@ if ($rpl_check_server_ids)
   }
 }
 
-# $rpl_master_list must be set so that include/rpl_change_topology.inc
-# knows which servers are initialized and not.
+if ($rpl_debug)
+{
+  --echo ---- Check the topology and call CHANGE MASTER ----
+}
+
+# $rpl_master_list must be set so that include/rpl_change_topology.inc and later
+# include/rpl_for_each_slave.inc knows which servers are initialized and not.
 --let $rpl_master_list= `SELECT REPEAT('x', $rpl_server_count * LENGTH($rpl_server_count))`
 --source include/rpl_change_topology.inc
 
 
 if (!$rpl_skip_start_slave)
 {
+  if ($rpl_debug)
+  {
+    --echo ---- Start slaves ----
+  }
   --source include/rpl_start_slaves.inc
 }
 
-
+if ($rpl_debug)
+{
+  --echo ---- Set connection to the server_1 ----
+}
 --let $rpl_connection_name= server_1
 --source include/rpl_connection.inc
 

mysql-test/include/wait_for_slave_io_to_start.inc

@@ -14,7 +14,8 @@
 #
 # Parameters:
 #   $slave_timeout
-#     See include/wait_for_slave_param.inc
+#     Timeout used when waiting for the slave IO thread to start.
+#     See include/wait_for_slave_param.inc.
 #
 #   $rpl_allow_error
 #     By default, this file fails if there is an error in the IO

mysql-test/include/wait_for_slave_sql_to_start.inc

@@ -11,6 +11,7 @@
 #
 # Parameters:
 #   $slave_timeout
+#     Timeout used when waiting for the slave SQL thread to start.
 #     See include/wait_for_slave_param.inc
 #
 #   $rpl_debug

mysql-test/include/wait_for_slave_to_start.inc

@@ -12,6 +12,7 @@
 #
 # Parameters:
 #   $slave_timeout
+#     Timeout used when waiting for the slave threads to start.
 #     See include/wait_for_slave_param.inc
 #
 #   $rpl_debug