It turns out that we must check for DISCARD TABLESPACE both
when the table is being rebuilt and when the AUTO_INCREMENT
value of the table is being added.

This was caught by the test innodb.alter_missing_tablespace.
Somehow I failed to run all tests. Sorry!

The statement ALTER TABLE...DISCARD TABLESPACE is problematic,
because its designed purpose is to break the referential integrity
of the data dictionary and make a table point to nowhere.

ha_innobase::commit_inplace_alter_table(): Check whether the
table has been discarded. (This is a bit late to check it, right
before committing the change.) Previously, we performed this check
only in a specific branch of the function commit_set_autoinc().

Note: We intentionally allow non-rebuilding ALTER TABLE even if
the tablespace has been discarded, to remain compatible with MySQL.
(See the various tests with "wl5522" in the name, such as
innodb.innodb-wl5522.)

The test case would crash starting with 10.3 only, but it does not hurt
to minimize the code and test difference between 10.2 and 10.3.

dict_load_table_low(): Copy the 'discarded' flag to file_unreadable.
This allows to avoid a potentially harmful call to dict_stats_init()
in ha_innobase::open().

The test that was added in commit e05650e6
would break a subsequent run of a test encryption.innodb-bad-key-change
because some pages in the system tablespace would be encrypted with
a different key.

The failure was repeatable with the following invocation:

./mtr --no-reorder \
encryption.create_or_replace,cbc \
encryption.innodb-bad-key-change,cbc

Because the crash was unrelated to the code changes that we reverted
in commit eb38b1f7
we can safely re-apply those fixes.

Add error printout when mysql.wsrep_streaming_log lock
fails. However, tests are very undeterministic and not
suitable for mtr environment. Thus, they are removed.

After DISCARD TABLESPACE, the tablespace of a table will no longer
exist, and dict_get_and_save_data_dir_path() would invoke
dict_get_first_path() to read an entry from SYS_DATAFILES.
For some reason, DISCARD TABLESPACE would not to remove the entry
from there.

dict_get_and_save_data_dir_path(): If the tablespace has been
discarded, do not bother trying to read the name.

Side note: The tables SYS_TABLESPACES and SYS_DATAFILES are
redundant and subject to removal in MDEV-22343.

This reverts commit e33f7b6f.
The change seems to have introduced intermittent failures of the test
encryption.innodb-bad-key-change on many platforms.

The failure that we were trying to address was not reproduced on 10.2.
It could be related to commit a7dd7c89
(MDEV-23651) or de942c9f (MDEV-15983)
or other changes that reduced contention on fil_system.mutex in 10.3.

The fix that we are hereby reverting from 10.2 seems to work fine
on 10.3 and 10.4.

We omit commit a3bdce8f
and commit a0e2a293
because they would make the test galera_3nodes.galera_gtid_2_cluster
fail and disable it.

This was forgotten in commit a9d8f5c1.

Let us shrink the test encryption.create_or_replace so that it can
run on the CI system, also on the embedded server.

encryption.create_or_replace_big: Renamed from the original test,
with the subset of encryption.create_or_replace omitted.

The test encryption.create_or_replace would occasionally fail with
a warning message from fil_check_pending_ops().

fil_crypt_find_space_to_rotate(): While waiting for available
I/O capacity, check fil_space_t::is_stopping() and release a
handle if necessary.

fil_space_crypt_close_tablespace(): Wake up the waiters in
fil_crypt_find_space_to_rotate().

log_group_read_log_seg() returns error when:

1) Calculated log block number does not correspond to read log block
number. This can be caused by:
  a) Garbage or an incompletely written log block. We can exclude this
  case by checking log block checksum if it's enabled(see innodb-log-checksums,
  encrypted log block contains checksum always).
  b) The log block is overwritten. In this case checksum will be correct and
  read log block number will be greater then requested one.

2) When log block length is wrong. In this case recv_sys->found_corrupt_log
is set.

3) When redo log block checksum is wrong. In this case innodb code
writes messages to error log with the following prefix: "Invalid log
block checksum."

The fix processes all the cases above.

Fix assertion text it was too tight for some systems.

This is backport from 10.4 and for Galera 3.

Fix assertion text it was too tight for some systems.

The presumed reason for the error is that the file was opened
by 3rd party antivirus or backup program, causing ERROR_SHARING_VIOLATION
on rename.

The fix, actually a workaround, is to retry MoveFileEx couple of times
before finally giving up. We expect 3rd party programs not to hold file
for extended time.

MDEV-23574 : galera_3nodes.galera_ipv6_mariabackup_section MTR failed: Could not open '../galera/include/have_mariabackup.inc'

Test case and configuration cleanup.

Add wait_condition to wait correct cluster configuration.

MDEV-21655 : galera.galera_wan_restart_ist MTR fails sporadically: WSREP did not transition to state READY

Replace sleeps with proper wait_conditions to wait correct
cluster configuration.

Made the test work with --repeat option by adding
galera_wait_ready.inc at the end of test. Recorded the test output.

MDEV-23617 : galera_sr.galera_sr_rollback_retry MTR failed: 1213: Deadlock found when trying to get lock

Add corrected wait_condition to wait until rows are in streaming
replication log.

Parse SHOW SLAVE STATUS output for the "Using_Gtid" column. If the value
is "No", then old log file and position is backed up, otherwise gtid_slave_pos
is backed up.

virtual column in index

Problem:
row_ins_foreign_fill_virtual was unconditionally set virtual fields to NULL
even though the field is not a part of a foreign key
(but a part of an index)

Solution:
The new virtual value should be computed with regard to cascade updates.

MDEV-23587 : galera_3nodes.galera_var_dirty_reads2 MTR failed: 1047: WSREP has not yet prepared node for application use

Add wait_condition tomake sure insert is replicated and server
is after isolation back on ready state.

- Changed the fil_space_set_recv_size_and_flags() to set the
tablespace size when size is not zero.

- Addressing ASAN failure in fts_check_aux_table()

Add wait_condition so that inserts to parent and child are replicated
and applied before we set debug sync point.

Remove incorrect BF (brute force) handling from lock_rec_has_to_wait_in_queue
and move condition to correct callers. Add a function to report
BF lock waits and assert if incorrect BF-BF lock wait happens.

wsrep_report_bf_lock_wait
	Add a new function to report BF lock wait.

wsrep_assert_no_bf_bf_wait
	Add a new function to check do we have a
	BF-BF wait and if we have report this case
	and assert as it is a bug.

lock_rec_has_to_wait
	Use new wsrep_assert_bf_wait to check BF-BF wait.

lock_rec_create_low
lock_table_create
	Use new function to report BF lock waits.

lock_rec_insert_by_trx_age
lock_grant_and_move_on_page
lock_grant_and_move_on_rec
	Assert that trx is not Galera as VATS is not compatible
	with Galera.

lock_rec_add_to_queue
	If there is conflicting lock in a queue make sure that
	transaction is BF.

lock_rec_has_to_wait_in_queue
	Remove incorrect BF handling. If there is conflicting
	locks in a queue all transactions must wait.

lock_rec_dequeue_from_page
lock_rec_unlock
	If there is conflicting lock make sure it is not
	BF-BF case.

lock_rec_queue_validate
	Add Galera record locking rules comment and use
	new function to report BF lock waits.

All attempts to reproduce the original assertion have been
failed. Therefore, there is no test case on this commit.