extra2_read_len resolved by keeping the implementation
in sql/table.cc by exposed it for use by ha_partition.cc

Remove identical implementation in unireg.h
(ref: bfed2c7d)

Per Marko's comment in JIRA, sql_kill is passing the thread id
as long long. We change the format of the error messages to match,
and cast the thread id to long long in sql_kill_user.

The 10.5 test error main.grant_kill showed up a incorrect
thread id on a big endian architecture.

The cause of this is the sql_kill_user function assumed the
error was ER_OUT_OF_RESOURCES, when the the actual error was
ER_KILL_DENIED_ERROR. ER_KILL_DENIED_ERROR as an error message
requires a thread id to be passed as unsigned long, however a
user/host was passed.

ER_OUT_OF_RESOURCES doesn't even take a user/host, despite
the optimistic comment. We remove this being passed as an
argument to the function so that when MDEV-21978 is implemented
one less compiler format warning is generated (which would
have caught this error sooner).

Thanks Otto for reporting and Marko for analysis.

commit '6de482a6'

10.3 no longer errors in truncate_notembedded.test
but per comments, a non-crash is all that we are after.

- InnoDB fails to skip newly created column while checking for
change column when table is in redundant row format. This issue
is caused the MDEV-18035 (ccb1acbd)

MDEV-23210 Assertion `(length % 4) == 0' failed in my_lengthsp_utf32 on ALTER TABLE, SELECT and INSERT

Problem:
Parse-time conversion from binary to tricky character sets like utf32
produced ill-formed strings. So, later a chash happened in debug builds,
or a wrong SHOW CREATE TABLE was returned in release builds.

Fix:

1. Backporting a few methods from 10.3:
  - THD::check_string_for_wellformedness()
  - THD::convert_string() overloads
  - THD::make_text_string_connection()

2. Adding a new method THD::reinterpret_string_from_binary(),
   which makes sure to either returns a well-formed string
   (optionally prepending with zero bytes), or returns an error.

mysqltest allows leading spaces before `--`, so mtr should too

whenever possible, partitioning should use the full
partition plugin name, not the one byte legacy code.

Normally, ha_partition can get the engine plugin from
table_share->default_part_plugin.

But in some cases, e.g. in DROP TABLE, the table isn't
opened, table_share is NULL, and ha_partition has to parse
the frm, much like dd_frm_type() does.

temporary_tables.cc, sql_table.cc:

When dropping a table, it must be deleted in the engine
first, then frm file. Because frm can be the only true
source of metadata that the engine might need for DROP.

table.cc:

when opening a partitioned table, if the engine for
partitions is not found, do not fallback to MyISAM.

not every index-using plan sets bits in table->quick_keys.
QUICK_ROR_INTERSECT_SELECT, for example, doesn't.

Use the fact that select->quick is set instead.

Also allow EXPLAIN to work.

Let us explicitly wait for purge before invoking a slow shutdown,
so that instrumented builds (such as ASAN or UBSAN) will not
exceed the 60-second timeout during shutdown.

The virtual member function that was added in
commit 1766a18e
needs to be declared "override".

The first step for deprecating innodb_autoinc_lock_mode(see MDEV-27844) is:
- to switch statement binlog format to ROW if binlog format is MIXED and
the statement changes autoincremented fields
- issue warnings if innodb_autoinc_lock_mode == 2 and binlog format is
STATEMENT

The warning out of OPTIMIZE
  Statement is unsafe because it uses a system function
was indeed counterfactual and was resulted by checking an
insufficiently strict property of lex' sql_command_flags.

Fixed with deploying an additional checking of weather
the current sql command that modifes a share->non_determinstic_insert
table is capable of generating ROW format events.
The extra check rules out the unsafety to OPTIMIZE et al, while the
existing check continues to do so to CREATE TABLE (which is
perculiarly tagged as ROW-event generative sql command).

As a side effect sql_sequence.binlog test gets corrected and
binlog_stm_unsafe_warning.test is reinforced to add up
an unsafe CREATE..SELECT test.

Travis is dead to us so we don't need all the conditions around it.

Remove depends for no longer supported versions

Debian Jessies, and Ubuntu Trusty, Xenial, Wily are all eol
as far as we are concerned.

The dependancy on an apt cache when running autobake broke the
10.2 aarch64 packages (MDEV-28014). Lets reduce the risk here.

zstd-1.1.3 is needed however stretch has only 1.1.2.

Move to distro version based checks as checks against the
apt-cache are unreliable if there is no cache.

Fixed typo in my_malloc_size_cb_func. There is no max-thread-mem-used
sys variable in MariaDB, only max-session-mem-used. The relevant entry
in sys_vars.cc is also fixed.

Added a fallback case in case we could allocate the 256 bytes for the
error message containing the exact setting.

MDEV-27025 allows to insert records before the record on which DELETE is
locked, as a result the DELETE misses those records, what causes serious ACID
violation.

Revert MDEV-27025, MDEV-27550. The test which shows the scenario of ACID
violation is added.

The virtual member function handler::reset_auto_increment(ulonglong)
is only ever invoked by the default implementation of the virtual
member function handler::truncate().

Because ha_innobase::truncate() overrides handler::truncate() without
ever invoking handler::truncate(), some InnoDB member functions are
never called.

ha_innobase::innobase_reset_autoinc(), ha_innobase::reset_auto_increment():
Removed (unreachable code).

ha_innobase::delete_all_rows(): Removed. The default implementation
handler::delete_all_rows() works just as fine.

- InnoDB FTS DDL decrements the FTS_DOC_ID when there is a
deleted marked record involved. FTS_DOC_ID must never be
reused. The purpose of FTS_DOC_ID is to be a unique row
identifier that will be changed whenever a fulltext indexed
column is updated.

btr_cur_optimistic_insert(): Disregard DEBUG_DBUG injection to
invoke btr_page_reorganize() if the page (and the table) is empty.
Otherwise, an assertion would fail in btr_page_reorganize_low()
because PAGE_MAX_TRX_ID is 0 in an empty secondary index leaf page.

Fixed by not sending --group option to the server (for now)

Reviwer: Sergei Golubchik

udf_handler::fix_fields(): Execute an assignment outside "if"
so that GCC 12 will not issue a bogus-looking warning.
Also, deduplicate some error handling code.

 - Server incorrectly downgrading the MDL after prepare phase when
table is empty. mdl_exclusive_after_prepare is being set in
prepare phase only. But mdl_exclusive_after_prepare condition was
misplaced and checked before prepare phase by
commit d270525d and it is now
changed to check after prepare phase.

 - main.innodb_mysql_sync test case was changed to avoid locking
optimization when table is empty.

In commit c7d04487 (MDEV-15132)
MariaDB Server 10.3 stopped writing the latest transaction identifier
to the TRX_SYS page. Instead, the transaction identifier will be
recovered from undo log pages.

Unfortunately, before commit 3926673c
and mysql/mysql-server@dc29792ff2996aefbb6e64bb2f0bc3aa8fc879e9
(MySQL 5.1.48 or MariaDB 5.1.48) InnoDB did not always initialize all
data fields, but some garbage could be left behind in unused parts
of data pages.

In undo log pages that are essentially free, but added to a list for
reuse (TRX_UNDO_CACHED) the TRX_UNDO_TRX_NO fields could contain garbage,
instead of 0. As long as such undo pages are being reused and never
marked completely free, the garbage contents may remain forever.
In fact, the function trx_undo_header_create() and the record
MLOG_UNDO_HDR_CREATE will only initialize TRX_UNDO_TRX_ID, but leave
TRX_UNDO_TRX_NO uninitialized.

trx_undo_mem_create_at_db_start(): Only read the TRX_UNDO_TRX_NO
fields of TRX_UNDO_CACHED pages if the TRX_UNDO_PAGE_TYPE is 0,
that is, the page was updated by MariaDB Server 10.3. Earlier versions
would always write the TRX_UNDO_PAGE_TYPE as 1 or 2.

trx_undo_header_create(): Zero out the TRX_UNDO_TRX_NO field.
Strictly speaking, this will change the semantics of the
MLOG_UNDO_HDR_CREATE record, but it should not do any harm to
overwrite a potentially garbage field with zeroes.

Note: This fix will only help future upgrades straight from
MariaDB Server 10.2 or MySQL 5.6 or earlier. If such an upgrade has
already been made, then an earlier server startup could have
fast-forwarded the transaction ID sequence to a large value.
If this large value cannot be represented in 48 bits (the size of
the DB_TRX_ID column in clustered index records), then various
strange things can happen.

DEBUG_SYNC signals can get lost in certain tests due to later
DEBUG_SYNC commands overwriting them. This patch addresses
these issues in three tests: main.query_cache_debug,
main.partition_debug_sync, and
rpl.rpl_dump_request_retry_warning.

Additionally, main.partition_debug_sync needed changes to the
result file (the others did not). The synchronization happened
between two commands, one based on ALTER, the other on DROP.
A new thread/connection was needed to synchronize the DEBUG_SYNC
actions between these commands, thereby changing the result file.
Additional comments were added for clarification.

Reviewed By:
============
Andrei Elkin <andrei.elkin@mariadb.com>