setup alternative name for rhel8/centos8

use correct C/C version when providing mariadb-connector-c
and other changes for installation over distro packages to work:

  dnf install mariadb-server
  dnf install --allowerasing MariaDB-{server,common,client,shared}*.rpm

When we move data we should fix buffer string length

under LOCK TABLES we still have to open everything, otherwise DML
prelocking will try to take an MDL on a table that wasn't in the
LOCK TABLES list.

%config(noreplace) /etc/security

only MDL-prelock but do not open FK child tables for read-only (RESTRICT)
FK actions.

Tables still needs to be opened for CASCADE actions, see 9180e866

We must ensure that the NUL will not terminate the query string.

Replace the 30-second sleep in the test with proper
DEBUG_SYNC interlocking.

MDEV-21437 MariaDB's SUSE/SLES packages don't "provide" all of the same capabilities as the platform's default packages

commit d467bb7e accidentally
broke the build without WSREP, by misplacing an #endif.

This is a partial backport of
commit 5e7e7153 from 10.4.

assert_trx_is_free(): Assert !is_wsrep().

trx_init(): Do not initialize trx->wsrep, because it must have been
initialized already.

trx_commit_in_memory(): Invoke wsrep_commit_ordered(). This call
was being skipped, because the transaction object had already been
freed to the pool.

trx_rollback_for_mysql(), innobase_commit_low(),
innobase_rollback_trx(): Always reset trx->wsrep.

- Instant alter should change the metadata alone when table is
discarded. It shouldn't try to add metadata record in clustered index.
Also make the clustered index to non-instant format.

		FOREIGN_KEY_CHECKS is disabled

- Referenced index can be null While renaming the referenced column name.
In that case, rename the referenced column name in dict_foreign_t and
find the equivalent referenced index.

- ALTER_ALGORITHM should be substituted when there is no mention of
algorithm in alter statement.
- Introduced algorithm(thd) in Alter_info. It returns the
user requested algorithm. If user doesn't specify algorithm explicitly then
it returns alter_algorithm variable.
- changed algorithm() to get_algorithm(thd) to return algorithm name for
displaying the error.
- set_requested_algorithm(algo_value) to avoid direct assignment on
requested_algorithm variable.
- Avoid direct access of requested_algorithm to encapsulate
requested_algorithm variable

- Added the test case to prove that alter_algorithm variable doesn't
affect when ALTER statement during PREPARE PHASE or CREATE PROCEDURE.
Only when execution/call happens, alter uses the alter_algorithm
variable when user does not mention algorithm explicitly

For a unique key if all the keyparts are NOT NULL or the predicates involving
the keyparts is NULL rejecting, then we can use EQ_REF access instead of ref
access with the unique key

Maybe this patch will help catch problems like buffer overflow.

log_t::first_in_use: removed

log_t::buf: this is where mtr_t are supposed to append data
log_t::flush_buf: this is from server writes to a file

Those two buffers are std::swap()ped when some thread is gonna write
to a file

queues.c cleanup and refactoring.

Restore old version of _downhead() (from before cd483c55)
that works well in an average case. Use it for queue_fix().

Move existing specialized version of _downhead() to queue_replace()
where it'll be handling the case it was specifically optimized for
(moving the element to the end of the queue).
And correct it to fix the heap not only down, but also up
(this fixes BUG#30301356).

Add unit tests.

Collateral cosmetic fixes.

CONCAT_WS didn't have it