Remove operations on fil_system.n_open from mariabackup, as they are not
protected by the mutex, and serve no higher purpose anyway.

058d93d4 introduced a switch in autobake
script to append dh-systemd package when it is necessary. However, the
change was not complete as it didn't actually remove the dh-systemd
dependency in debian/control.

after b9d64989 the test for MDEV-16962 is not suitable anymore
(and probably the bug is not reproducible).

1) Checked presence of mysys_var.
2) Removed unneeded thd_clear_errors,
  its content added to THD::change_user.

The test innodb.doublewrite could occasionally fail with 64KiB page size
because the page 0 would no longer be in the doublewrite buffer.
Let us stop purge before the server is killed, and ensure that
the entire buffer pool will be flushed before we initiate an extra
write of page 0.

Fixed NULL pointer reference to db.str

Keep the readline installation step in Salsa-CI stages that install
MariaDB.org packages in Debian Sid (or releases after is, such as
Debian 11 "Bullseye" or Ubuntu 21.04 "Hirsute") as those old packages
still depend on readline for the MariaDB Server itself.

When you only need view structure, don't call handle_derived with
DT_CREATE and rely on its internal hackish check to skip DT_CREATE.
Because handle_derived is called from many different places,
and this internal hackish check is indiscriminative.

Instead, just don't ask handle_derived to do DT_CREATE
if you don't want it to do DT_CREATE.

galera_var_wsrep_on_off : Add wait conditions to make sure DDL is
replicated before continuing.

wsrep.[variables|variables_debug] :  Remove unnecessary parts
and add check to correct number of variables or skip

galera_ssl_reload: Add version check and SSL checks.

Fix a race condition in the testcase. The testcase assumed that
State='Sending data' means that the thread is already in an
InnoDB lock wait. This is not case, there is a gap between the
state changing to Sending data and execution reaching the point
where it is waiting for a lock.

Use a more precise check instead, through I_S.INNODB_TRX.

The problem was caused by the following scenario:

Subquery's table has two indexes, KEY a(a), KEY a_b(a,b)

- LATERAL DERIVED optimization decides to use index a.
  = The subquery uses ref access over key a.
- test_if_skip_sort_order() sees that KEY a_b satisfies the
  subquery's GROUP BY clause, and attempts to switch to it.
  = It fails to do so, because KEYUSE objects for index a_b
    are switched off.

Fixed by disallowing to change the ref access key if it uses KEYUSE
objects injected by LATERAL DERIVED optimization.

Problem:
========
180511 11:07:58 [ERROR] Slave I/O: Unexpected master's heartbeat data:
heartbeat is not compatible with local info;the event's data: log_file_name
mysql-bin.000009 log_pos 1054262041, Error_code: 1623

Analysis:
=========
In replication setup when master server doesn't have any events to send to
slave server it sends an 'Heartbeat_log_event'. This event carries the
current binary log filename and offset details. The offset values is stored
within 4 bytes of event header. When the size of binary log is higher than
UINT32_MAX the log_pos values will not fit in 4 bytes memory.  It overflows
and hence slave stops with an error.

Fix:
===
Since we cannot extend the common_header of Log_event class, a greater than
4GB value of Log_event::log_pos is made to be transported with a HeartBeat
event's sub-header.  Log_event::log_pos in such case is set to zero to
indicate that the 8 byte sub-header is allocated in the event.

In case of cross version replication following behaviour is expected

OLD - Server without fix
NEW - Server with fix

OLD<->NEW : works bidirectionally as long as the binlog offset is
            (normally) within 4GB.

When log_pos > UINT32_MAX
OLD->NEW  : The 'log_pos' is bound to overflow and NEW slave may report
            an invalid event/incompatible heart beat event error.
NEW->OLD  : Since patched server sets log_pos=0 on overflow, OLD slave will
            report invalid event error.

- Fixing post-push failure of innodb_fts_misc_1 test case.

This happens during repair when a temporary table is opened
with HA_OPEN_COPY, which resets 'share->born_transactional', which
the encryption code did not like.

Fixed by resetting just share->now_transactional.

MDEV-22265 Connect string character limit too small for full 64 character InnoDB table-name limit when using ad-hoc Spider server definitions.

Fix length for getting default table name.

InnoDB tries to fetch the deleted doc ids for discarded
tablespace. In i_s_fts_deleted_generic_fill(), InnoDB needs
to check whether the table is discarded or not before fetching
deleted doc ids.

fil_ibd_load(): Remove a message that is basically saying that
everything works as expected. The other "Ignoring data file" message
about the presence of an extraneous file will be retained
(and expected by the test innodb.log_file_name).

This reverts commit 8880dff2.

MDEV-25530 Error 1451 on slave: Cannot delete or update a parent row: a foreign key constraint fails

after dfb41fdd tables that failed to drop are excluded from the
binlogged DROP TABLE statement. It means that the slave should not
expect any errors when executing DROP TABLE, and the binlog should
report that no error has happened, even if it was.

Do not write error code into the binlogged DROP TABLE,
and remove all code that was needed to compute it.

MDEV-22265 Connect string character limit too small for full 64 character InnoDB table-name limit when using ad-hoc Spider server definitions.

Fix length for getting default table name.

This commits replaces the call of the function setup_tables() with
a call of the function setup_tables_and_check_access() in the method
Multiupdate_prelocking_strategy::handle_end().
There is no known bug that would require this change. However the change
aligns this piece of code with the code existed before the patch for
MDEV-24823.

MDEV-25501 routine_definition in information_schema.routines loses tablename if it starts with an _ and is not backticked

remove code duplication in Lex_input_stream::scan_ident_middle(),
make sure identifiers are always use the same code path whether
they start form an underscore or not.

The assert is no more reproducible in the lastest 10.5-10.6

The patch only adds testcase from MDEV-24382.