The real fix for MDEV-15532 will be pushed into 10.2 and 10.6
This is an additional fix for 10.4.

In 10.4 trans_xa_detach was introduced.  However THD::cleanup() assumes
that after trans_xa_detach() is done, there is no registered transactions
anymore. In the 10.2 patch there will be an assert to ensure this, which
will cause 10.4 to fail.

The fix used is to reset the transaction flags in trans_xa_detach().

Problem:
========
When O_TMPFILE is not supported mysqlbinlog outputs the error to standard
stream as a warning which breaks PITR:

ERROR 1064 (42000) at line 382: You have an error in your SQL syntax; check
the manual that corresponds to your MariaDB server version for the right
syntax to use near 'mysqlbinlog: O_TMPFILE is not supported on /tmp (disabling
    future attempts)

Analysis:
=========
'mysqlbinlog' utility is used to perform point-in-time-recovery based on binary
log. It converts the events in the binary log files, from binary format to text
so that they can be viewed or applied. This output can be saved to a file and
it can be sourced back to mysql client. The mysqlbinlog utility stores the
text output into IO_CACHE and when it is full the data is written to a temp
file.  The temporary file creation is attempted using 'O_TMPFILE' flag. If the
underlying filesystem doesn't support this operation, a note is printed on to
standard error and file creation is done without O_TMPFILE' flag. If standard
error is redirected to standard output the note gets written to the sql file
as shown below.

/bld/client/mysqlbinlog: O_TMPFILE is not supported on /tmp (disabling future
    attempts)
table id 32

When the sql file is used for PITR, it leads to a syntax error as it is not a
valid sql command.

Fix:
====
Make 'my_message_stderr' to ignore messages which are flagged as ME_NOTE and
ME_ERROR_LOG_ONLY. ME_ERROR_LOG_ONLY flag is applicable to server. In order to
print an informational note to stderr stream, ME_NOTE flag without
ME_ERROR_LOG_ONLY flag should be specified. 'my_message_stderr' should print
messages flagged with ME_WARNING or ME_FATAL to stderr stream.

Removed
* lp1376747-4
* MDEV-16509
* galera_defaults

Make sure that we operate with correct Galera library version
and do not print wsrep_provider_options field.

Test galera_parallel_apply_3nodes started to failed occasionally.
The test assumes that one round of autocommit retry is sufficient in
order to avoid a deadlock error when two conflicting UPDATE statements
run concurrently.
This assumption no longer holds after galera library has changed
last_committed() to return the seqno of the last transaction that left
apply monitor, rather than commit monitor. So it is possible that
after a BF abort, a command is re-executed before it's BF abortee has
left the apply monitor. Thus causing another retry or a deadlock error.
Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>

MDEV-21523 : galera.MDEV-16509 MTR failed: timeout after 900 seconds: Can't connect to local MySQL server

Add requirement for debug-build.

Add wait conditions.

The data member tv_usec of the struct timeval is declared as suseconds_t
on MacOS. Size of suseconds_t is 4 bytes. On the other hand, size of ulong
is 8 bytes on 64-bit MacOS, so attempt to assign a value of wider type
(usec) to a value (tv_usec) of narrower type leads to error.

The fix of MDEV-23456 (commit b1009ae5)
introduced a livelock between page flushing and a thread that is
executing buf_page_create().

buf_page_create(): If the current mini-transaction is holding
an exclusive latch on the page, do not attempt to acquire another
one, and do not care about any I/O fix.

mtr_t::have_x_latch(): Replaces mtr_t::get_fix_count().

dyn_buf_t::for_each_block(const Functor&) const: A new variant.

rw_lock_own(): Add a const qualifier.

Reviewed by: Thirunarayanan Balathandayuthapani

Due to a premature cleanup of the unit that specified a recursive CTE
used in the second operand of union the server fell into an infinite
loop in the reported test case. In other cases this premature cleanup
could cause other problems.
The bug is the result of a not quite correct fix for MDEV-17024. The
unit that specifies a recursive CTE has to be cleaned only after the
cleanup of the last external reference to this CTE. It means that
cleanups of the unit triggered not by the cleanup of a external
reference to the CTE must be blocked.
Usage of local table chains in selects to get external references to
recursive CTEs was not correct either because of possible merges of
some selects.

Also fixed a minor bug in st_select_lex::set_explain_type() that caused
typing 'RECURSIVE UNION' instead of 'UNION' in EXPLAIN output for external
references to a recursive CTE.

Analysis:
========
Writes to 'rli->log_space_total' needs to be synchronized, otherwise both
SQL_THREAD and IO_THREAD can try to modify the variable simultaneously
resulting in incorrect rli->log_space_total.  In the current test scenario
SQL_THREAD is trying to decrement 'rli->log_space_total' in 'purge_first_log'
and IO_THREAD is trying to increment the 'rli->log_space_total' in
'queue_event' simultaneously. Hence test occasionally fails with  result
mismatch.

Fix:
===
Convert 'rli->log_space_total' variable to atomic type.

A follow-up fix, for original fix for MDEV-21577, which did not handle well
temporary tables.

OPTIMIZE and REPAIR TABLE statements can take a list of tables as argument,
and some of the tables may be temporary. Proper handling of temporary tables
is to skip them and continue working on the real tables. The bad version, skipped all tables,
if a single temporary table was in the argument list. And this resulted so that FK parent
tables were not scnanned for the remaining real tables. Some mtr tests, using OPTIMIZE or REPAIR
for temporary tables caused regressions bacause of this, e.g. galera.galera_optimize_analyze_multi

The fix in this PR opens temporary and real tables first, and in the table handling loop skips
temporary tables, FK parent scanning is done only for real tables.

The test has new scenario for OPTIMIZE and REPAIR issued for two tables of which one is temporary table.
Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>

This PR fixes same issue as MDEV-21577 for TRUNCATE TABLE.
MDEV-21577 fixed TOI replication for OPTIMIZE, REPAIR and ALTER TABLE
operating on FK child table. It was later found out that also TRUNCATE
has similar problem and needs a fix.

The actual fix is to do FK parent table lookup before TRUNCATE TOI
isolation and append found FK parent table names in certification key
list for the write set.

PR contains also new test scenario in galera_ddl_fk_conflict test where
FK child has two FK parent tables and there are two DML transactions operating
on both parent tables.

For development convenience, new TO isolation macro was added:
WSREP_TO_ISOLATION_BEGIN_IF and WSREP_TO_ISOLATION_BEGIN_ALTER macro was changed
to skip the goto statement.
Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>

As noted in commit 0b66d3f7,
MariaDB does not support CREATE TABLESPACE for InnoDB.
Hence, some code that was added in
commit fec844ac
and originally in
mysql/mysql-server@c71dd213bd434c0579e454ab8880e6d3756b0fb0
is unused in MariaDB and should be removed.

trx_undo_left(): Return 0 in case of an overflow, instead of
returning a negative number interpreted as a large positive number.
Also, add debug assertions to check that the pointer is within
the page area. This should allow us to catch bugs like
MDEV-24096 easier in the future.

The function ibuf_merge_or_delete_for_page() was always being
invoked with update_ibuf_bitmap=true ever since
commit cd623508
fixed up something after MDEV-9566.

Furthermore, the parameter page_size is never being passed as a
null pointer, and therefore it should better be a reference to
a constant object.

Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>

- Patch 95bb3cb8 used `my_which` function in `10.2`
- Based on patch `355ee687` from 10.3+ `command -v` is used instead of
`my_which` so we are changing in this patch also
- `ldconfig` is usually found in `/sbin` so make sure it is added in
`$PATH` variable