The function mach_read_ulint() is a wrapper for the lower-level
functions mach_read_from_1(), mach_read_from_2(), mach_read_from_8().
Invoke those functions directly, for better readability of the code.

mtr_t::read_ulint(), mtr_read_ulint(): Remove. Yes, we will lose the
ability to assert that the read is covered by the mini-transaction.
We would still check that on writes, and any writes that
wrongly bypass mini-transaction logging would likely be caught by
stress testing with Mariabackup.

Always use the MLOG_MEMSET record for writing FIL_NULL,
because it is more compact.

Due to MDEV-12288, the slow shutdown in MariaDB 10.3 will include
resetting the DB_TRX_ID for all inserted records. This might
cause the 60-second shutdown_server timeout to be exceeded.
Let us wait for the purge to complete before initiating slow shutdown.

dict_index_add_to_cache(): Make the 'index' a reference to a pointer,
so that the caller will avoid the expensive call to
dict_index_get_if_in_cache_low().

Due to a data corruption bug that may have occurred a long time earlier
(possibly involving physical backup and MySQL Bug #69122, which was
addressed in commit f166ec71)
it seems possible that the InnoDB change buffer might end up containing
entries, while no buffered changes exist according to the change buffer
bitmap pages in the .ibd files.

ibuf_delete_recs(): New function, to be invoked on slow shutdown only.
Remove all buffered changes for a specific page.

ibuf_merge_or_delete_for_page(): If the change buffer bitmap is clean
and a slow shutdown is in progress, invoke ibuf_delete_recs().
We do not want to do that during normal operation, due to the additional
overhead that is involved. The bitmap page should be consistent with
the change buffer in the first place.

InnoDB: Assertion failure in file .../dict/dict0dict.cc line ...
InnoDB: Failing assertion: table->can_be_evicted

This fixes a regression that was caused by the fix of MDEV-20621
(commit a41d4297).
MySQL 5.6 (and MariaDB 10.0) introduced eviction of tables from
the InnoDB data dictionary cache. Tables that are connected to
FOREIGN KEY constraints or FULLTEXT INDEX are exempt of the eviction.
With the problematic change, a table that would already be exempt
from eviction due to FOREIGN KEY would cause the problem if there
also was a FULLTEXT INDEX defined on it.

dict_load_table(): Only prevent eviction if table->can_be_evicted holds.

Do not rely on existence of CMakeFiles/${target}.dir directory existence
It is not there for custom targets in Ninja build.

Don't save/restore HP_INFO as it could be changed by a concurrent thread.
different parts of HP_INFO are protected by different mutexes and
the mutex that protect most of the HP_INFO does not protect its open_list
data.

As a bonus, make heap_check_heap() to take const HP_INFO* and not
make any changes there whatsoever.

dict_table_rename_in_cache(): Use strcpy() instead of strncpy(),
because they are known to be equivalent in this case (the length
of old_name was already validated).

mariabackup: Invoke strncpy() with one less than the buffer size,
and explicitly add NUL as the last byte of the buffer.

This reverts commit dacd1794.

Do the same that newer branches do and don't include glibc-related headers on non-glibc environment.

- Add SLEEP() calls to the testcase to make it really test that the
  time doesn't change.
- Always use .frm file creation time as a creation timestamp (attempts
  to re-use older create_time when the table DDL changes are not good
  because then create_time will change after server restart)
- Use the same method names as the upstream patch does
- Use std::atomic for m_update_time

wsrep_init_provider_status_variables(): Always set wsrep_inited
to ensure that the memory will be freed.

The initial patch was provided by Julius Goryavsky.

In the function prev_record_reads where one finds the different row combinations for a
subset of partial join, it did not take into account the selectivity of tables
involved in the subset of partial join.

dict_index_add_to_cache_w_vcol(): merge with dict_index_add_to_cache()

Unfortunate DROP TEMPORARY..IF EXISTS on a regular table may allow
subsequent CREATE TABLE statements to steal away the PFS_table_share
instance from the dropped table.

Variant#5 of the patch:
- take creation date from the .frm file, like InnoDB does
- Update_time is in-memory only (like in InnoDB).

innobase_drop_foreign_try(): Don't evict and reload the dict_foreign_t
during instant ALTER TABLE if the FOREIGN KEY constraint is being
dropped.

The MDEV-19630 fix (commit 07b1a26c)
was incomplete, because it did not cover a case where the
FOREIGN KEY constraint is being dropped.

MDEV-18244 Server crashes in ha_innobase::update_thd / ... / ha_partition::update_next_auto_inc_val.

Partition table with the AUTO_INCREMENT column we ahve to check if the
max value is properly loaded. So we need to open all tables in INSERT
PARTITION statement if necessary. Also we need to check if some
tables are pruned away and not count the max autoincrement in this case.

Variant#5 of the patch:
- take creation date from the .frm file, like InnoDB does
- Update_time is in-memory only (like in InnoDB).