This will allow us to in the future add better error messages why
an Aria table is crashed.

Added name of the dll/udf that caused the error.

- Slave_IO thread time is now reset between reading events. Before
  this commit Slave_IO always showed "Waiting for master to send
  event" and the time was from SLAVE START. Now it shows time since
  reading last event.

This is to make it easier to understand why master_pos_wait() fails in mtr.

This commit can be ignored when columnstore changes to use
rows_stats.updated+rows_stats.rows_inserted+rows_stats.rows_deleted
instead of 'rows_changed'
in storage/columnstore/columnstore/dbcon/mysql/ha_mcs_impl.cpp

MDEV-34031 FLUSH QUERY_RESPONSE_TIME_WRITE also flushes READ, and vice versa

This is to update the plugin to be compatible with Percona's
query_response_time plugin, with some additions.
Some of the tests are taken from Percona server.

- Added plugins QUERY_RESPONSE_TIME_READ, QUERY_RESPONSE_TIME_WRITE and
  QUERY_RESPONSE_TIME_READ_WRITE.
- Added option query_response_time_session_stats, with possible values
  GLOBAL, ON or OFF, to the query_response_time plugin.

Notes:
- All modules are dependent on QUERY_RESPONSE_READ_TIME. This must always
  be enabled if any of the other modules are used.
  This will be auto-enabled in the near future.
- Accounting are done per statement. Stored functions are regarded
  as part of the original statement.
- For stored procedures the accounting are done per statement executed
  in the stored procedure. CALL will not be accounted because of this.
- FLUSH commands will not be accounted for. This is to ensure that
  FLUSH QUERY_RESPONSE_TIME is not part of the statistics.
  (This helps when testing with mtr and otherwise).
- Use drop_table() instead of ha_drop_table() for internal temporary
  tables to avoid information_schema queries to be categorized as
  write queries.
- FLUSH QUERY_RESPONSE_TIME_READ and FLUSH QUERY_RESPONSE_TIME_READ
  only resets the corresponding status.
- FLUSH QUERY_RESPONSE_TIME and FLUSH QUERY_RESPONSE_TIME_READ_WRITE or
  changing the value of query_response_time_range_base followed by
  any FLUSH of QUERY_RESPOSNSE_TIME resets all status.
- query_response_time_flush was removed as it is not needed.

MDEV-33901 INDEX_STATISTICS.QUERIES is incremented additionally for subqueries

Other changes:
- Do not collect index statistics for system tables like index_stats
  table_stats, performance_schema, information_schema etc as the user
  has no control of these and the generate noise in the statistics.

MDEV-33881 Userstat skips system tables inconsistently
MDEV-33913 TABLE_STATISTICS increments ROWS_CHANGED twice upon UPDATE and
           does not count DELETE

Columns added to TABLE_STATISTICS
- ROWS_INSERTED, ROWS_DELETED, ROWS_UPDATED, KEY_READ_HITS and
  KEY_READ_MISSES.

Columns added to CLIENT_STATISTICS and USER_STATISTICS:
- KEY_READ_HITS and KEY_READ_MISSES.

User visible changes (except new columns):
- CLIENT_STATISTICS and USER_STATISTICS has columns KEY_READ_HITS and
  KEY_READ_MISSES added after column ROWS_UPDATED before SELECT_COMMANDS.

Other changes:
- Do not collect table statistics for system tables like index_stats
  table_stats, performance_schema, information_schema etc as the user
  has no control of these and the generate noice in the statistics.
- All row variables that are part of user_stats are moved to
  'struct rows_stats' to make it easy to clear all of them at once.
- ha_read_key_misses added to STATUS_VAR
- Fixed that all no tables in 'mysql' schema are not included in userstat.
  A benefit of this is that the server is not reading statistics tables
  if mysql.proc or other tables in mysql is accessed.

Notes:
- userstat.result has a change of numbers of rows for handler_read_key.
  This is because use-stat-tables is now disabled for the test.

This task is inspired by the Percona implementation of
slow_query_log_always_write_time.

This task implements the variable log_slow_always_query_time (name
matching other MariaDB variables using the slow query log). The
default value for the variable is 31536000, which makes MariaDB
compatible with older installations.

For queries with execution time longer than log_slow_always_query_time
the variables log_slow_rate_limit and log_slow_min_examined_row_limit
will be ignored and the query will be written to the slow query log
if there is no other limitations (like log_slow_filter etc).

Other things:
- long_query_time internal variable renamed to log_slow_query_time.
- More descriptive information for "log_slow_query_time".

MDEV-33680 Server hangs or assertion fails upon SELECT with
           limited max_tmp_space_usage
MDEV-33751 Assertion `thd' failed in int
           temp_file_size_cb_func(tmp_file_tracking*, int)
MDEV-34060 Unexpected behavior upon reading I_S.ALL_PLUGINS
           under limited tmp space.
MDEV-34142 Server crashes in create_internal_tmp_table with low tmp space limit
MDEV-34150 Assertion failure in Diagnostics_area::set_error_status upon binary logging hitting tmp space limit

Two new variables added:
- max_tmp_space_usage : Limits the the temporary space allowance per user
- max_total_tmp_space_usage: Limits the temporary space allowance for
  all users.

New status variables: tmp_space_used & max_tmp_space_used
New field in information_schema.process_list: TMP_SPACE_USED

The temporary space is counted for:
- All SQL level temporary files. This includes files for filesort,
  transaction temporary space, analyze, binlog_stmt_cache etc.
  It does not include engine internal temporary files used for repair,
  alter table, index pre sorting etc.
- All internal on disk temporary tables created as part of resolving a
  SELECT, multi-source update etc.

Special cases:
- When doing a commit, the last flush of the binlog_stmt_cache
  will not cause an error even if the temporary space limit is exceeded.
  This is to avoid giving errors on commit. This means that a user
  can temporary go over the limit with up to binlog_stmt_cache_size.

Noteworthy issue:
- One has to be careful when using small values for max_tmp_space_limit
  together with binary logging and with non transactional tables.
  If a the binary log entry for the query is bigger than
  binlog_stmt_cache_size and one hits the limit of max_tmp_space_limit
  when flushing the entry to disk, the query will abort and the
  binary log will not contain the last changes to the table.
  This will also stop the slave!
  This is also true for all Aria tables as Aria cannot do rollback
  (except in case of crashes)!
  One way to avoid it is to use @@binlog_format=statement for
  queries that updates a lot of rows.

Implementation:
- All writes to temporary files or internal temporary tables, that
  increases the file size, are routed through temp_file_size_cb_func()
  which updates and checks the temp space usage.
- Most of the temporary file monitoring is done inside IO_CACHE.
  Temporary file monitoring is done inside the Aria engine.
- MY_TRACK and MY_TRACK_WITH_LIMIT are new flags for ini_io_cache().
  MY_TRACK means that we track the file usage. TRACK_WITH_LIMIT means
  that we track the file usage and we give an error if the limit is
  breached. This is used to not give an error on commit when
  binlog_stmp_cache is flushed.
- global_tmp_space_used contains the total tmp space used so far.
  This is needed quickly check against max_total_tmp_space_usage.
- Temporary space errors are using EE_LOCAL_TMP_SPACE_FULL and
  handler errors are using HA_ERR_LOCAL_TMP_SPACE_FULL.
  This is needed until we move general errors to it's own error space
  so that they cannot conflict with system error numbers.
- Return value of my_chsize() and mysql_file_chsize() has changed
  so that -1 is returned in the case my_chsize() could not decrease
  the file size (very unlikely and will not happen on modern systems).
  All calls to _chsize() are updated to check for > 0 as the error
  condition.
- At the destruction of THD we check that THD::tmp_file_space == 0
- At server end we check that global_tmp_space_used == 0
- As a precaution against errors in the tmp_space_used code, one can set
  max_tmp_space_usage and max_total_tmp_space_usage to 0 to disable
  the tmp space quota errors.
- truncate_io_cache() function added.
- Aria tables using static or dynamic row length are registered in 8K
  increments to avoid some calls to update_tmp_file_size().
- Added Max_tmp_disk_space_used to slow query log.
- Fixed some bugs in log_slow_innodb.test
- Fixed that Filesort_on_disk in slow query log works again
  (A commit in 10.10 caused it to be always 'No')
- Fixed bug in subselect3.inc which caused following test to use
  heap tables with low value for max_heap_table_size
- Fixed bug in sql_expression_cache where it did not overflow
  heap table to Aria table.
- Fixed that MyISAM and Aria parallel repair works with tmp file limit.
  This required to add current_thd to all parallel workers and add
  protection in my_malloc_size_cb_func() and temp_file_size_cb_func() to
  be able to handle shared THD's.  I removed the old code in MyISAM to
  set current_thd() as only worked when using with virtal indexed
  columns and I wanted to keep the Aria and MyISAM code identical.
- Change variable names in commit to
  max_tmp_session_space_usage and max_tmp_total_space_usage
- Moved writing to binlog_cache from close_thread_tables() to
  binlog_commit().
- In select_create() delete cached row events instead of flushing them
  to disk. This was done to avoid possible disk write error in this code.

Other things:
- Ensure that all handler errors are registered.  Before, some engine
  errors could be printed as "Unknown error".
- Fixed bug in filesort() that causes a assert if there was an error
  when writing to the temporay file.
- Fixed that compute_window_func() now takes into account write errors.
- In case of parallel replication, rpl_group_info::cleanup_context()
  could call trans_rollback() with thd->error set, which would cause
  an assert. Fixed by resetting the error before calling trans_rollback().
Other things:
- Improved error messages from Aria parallel repair and
  create_internal_tmp_table_from_heap().

- FLUSH GLOBAL STATUS now resets most global_status_vars.
  At this stage, this is mainly to be used for testing.
- FLUSH SESSION STATUS added as an alias for FLUSH STATUS.
- FLUSH STATUS does not require any privilege (before required RELOAD).
- FLUSH GLOBAL STATUS requires RELOAD privilege.
- All global status reset moved to FLUSH GLOBAL STATUS.
- Replication semisync status variables are now reset by
  FLUSH GLOBAL STATUS.
- In test cases, the only changes are:
  - Replace FLUSH STATUS with FLUSH GLOBAL STATUS
  - Replace FLUSH STATUS with FLUSH STATUS; FLUSH GLOBAL STATUS.
    This was only done in a few tests where the test was using SHOW STATUS
    for both local and global variables.
- Uptime_since_flush_status is now always provided, independent if
  ENABLED_PROFILING is enabled when compiling MariaDB.
- @@global.Uptime_since_flush_status is reset on FLUSH GLOBAL STATUS
  and @@session.Uptime_since_flush_status is reset on FLUSH SESSION STATUS.
- When connected, @@session.Uptime_since_flush_status is set to 0.

Added SHOW_LONGLONG_NOFLUSH to mark the variables that should not be
flushed.

New variables cleared as part of SHOW STATUS:
- Rpl_semi_sync_master_request_ack
- Rpl_semi_sync_master_get_ac
- Rpl_semi_sync_slave_send_ack
- Slave_skipped_error

This was caused by the patch for
MDEV-32567 Remove thr_alarm from server codebase

During the build process this is wrapped into plugin_auth.h.

MariaDB debian control files are slightly in disorder
run wrap-and-sort tool against them shows some minor
changes.

Fix Debian .install files to alphabetically ordered from
mostly ordered state.

This is a refactoring patch, it does not change the behaviour.
The MTR tests are being added only to cover the LIKE predicate better.
(these tests should have been added earlier under terms of MDEV 9711).
This patch does not need its own specific MTR tests.

Moving the duplicate code into a new shared file ctype-wildcmp.inl
and including it from multiple places, to define the following functions:

- my_wildcmp_uca_impl(), in ctype-uca.c

  For utf8mb3, utf8mb4, ucs2, utf16, utf32, using cs->cset->mb_wc().
  For UCA based collations.

- my_wildcmp_mb2_or_mb4_general_ci_impl(), in ctype-ucs2.c:

  For ucs2, utf16, utf32, using cs->cset->mb_wc().
  For general_ci-style collations:
      - xxx_general_ci
      - xxx_general_mysql500_ci
      - xxx_general_nopad_ci

- my_wildcmp_mb2_or_mb4_bin_impl(), in ctype-ucs2.c:

  For ucs2, utf16, utf32, using cs->cset->mb_wc().
  For _bin collations:
      - xxx_bin
      - xxx_nopad_bin

- my_wildcmp_utf8mb3_general_ci_impl(), in ctype-utf8.c

  Optimized for utf8mb3, using my_mb_wc_utf8mb3_quick().

  For general_ci-style collations:
      - utf8mb3_general_ci
      - utf8mb3_general_mysql500_ci
      - utf8mb3_general_nopad_ci

- my_wildcmp_utf8mb4_general_ci_impl(), in ctype-utf8.c

  Optimized for utf8mb4, using my_mb_wc_utf8mb4_quick().

  For general_ci-style collations:
      - utf8mb4_general_ci
      - utf8mb4_general_nopad_ci

New tests display additional information about characters from the BMP range:

- A summary with a COUNT(*) for all distinct combinations of properties
  telling how the "=" and the "LIKE" predicates compare characters to their
  LOWER() and UPPER() variants.

- A detailed list of trciky characters
  for which the "=" and the "LIKE" predicates compare
  LOWER(c)/UPPER(c) variants as not equal to just "c".

Tricky characters include:
 - Turkish letters: ı - small dotless letter i
 - Croatian letters: precombined contractions for Dž, Dz, Lj, Nj
 - Units of measurement: Ω,K,Å (Ohm, Kelvin, Angstrom)
   These ones look very similar to Greek letter Omega,
   Latin letter Kra, Swedish/Finnish letter A with a ring above.

Under terms of MDEV 27490 we'll add support for non-BMP identifiers
and upgrade casefolding information to Unicode version 14.0.0.
In Unicode-14.0.0 conversion to lower and upper cases can increase octet length
of the string, so conversion won't be possible in-place any more.

This patch removes virtual functions performing in-place casefolding:
  - my_charset_handler_st::casedn_str()
  - my_charset_handler_st::caseup_str()
and fixes the code to use the non-inplace functions instead:
  - my_charset_handler_st::casedn()
  - my_charset_handler_st::caseup()

Only add innodb_async_reads/writes_total_count here.
For all other counters, writing reproducible tests is rather tricky.

Requested by Marko during review

Provide some statistics about asynchronous IO reads and writes:
 - number of pending operations
 - number of completion callbacks that are currently being executed
 - number of completion callbacks that are currently queued
   (due to restriction on number of IO threads)
 - total number of IOs finished
 - total time to wait for free IO slot
 - total number of completions that were queued.

Also revert tpool InnoDB perfschema instrumentation (MDEV-31048)
That instrumentation of cache mutex did not bring any revelation (
the mutex is taken for a couple of instructions), and made it impossible
to use tpool outside of the server (e.g in mariadbimport/dump)

- Add `as <int_type>` to sequence creation options
  - int_type can be signed or unsigned integer types, including
    tinyint, smallint, mediumint, int and bigint
  - Limitation: when alter sequence as <new_int_type>, cannot have any
    other alter options in the same statement
  - Limitation: increment remains signed longlong, and the hidden
    constraint (cache_size x abs(increment) < longlong_max) stays for
    unsigned types. This means for bigint unsigned, neither
    abs(increment) nor (cache_size x abs(increment)) can be between
    longlong_max and ulonglong_max
- Truncating maxvalue and minvalue from user input to the nearest max
  or min value of the type, plus or minus 1. When the truncation
  happens, a warning is emitted
- Information schema table for sequences

After MDEV-31400, plugins are allowed to ask for retries when failing
initialisation. However, such failures also cause plugin system
variables to be deleted (plugin_variables_deinit()) before retrying
and are not re-added during retry.

We fix this by checking that if the plugin has requested a retry the
variables are not deleted. Because plugin_deinitialize() also calls
plugin_variables_deinit(), if the retry fails, the variables will
still be deleted.

Alternatives considered:

- remove the plugin_variables_deinit() from plugin_initialize() error
handling altogether. We decide to take a more conservative approach
here.

- re-add the system variables during retry. It is more complicated
than simply iterating over plugin->system_vars and call
my_hash_insert(). For example we will need to assign values to
the test_load field and extract more code from test_plugin_options(),
if that is possible.

followup for abcd23ad

it was able to enable --ssl-verify-server-cert if explicily requested,
now it can also disable it, if explicitly requested.

In case of failure, the something like the following is now printed:

Slave position:  file: binary.000004  position: 3647
Master position: file: binary.000004  position: 3647

binlog_space_limit is a variable in Percona server used to limit the total
size of all binary logs.

This implementation is based on code from Percona server 5.7.

In MariaDB we decided to call the variable max-binlog-total-size to be
similar to max-binlog-size. This makes it easier to find in the output
from 'mariadbd --help --verbose'). MariaDB will also support
binlog_space_limit for compatibility with Percona.

Some internal notes to explain implementation notes:

- When running MariaDB does not delete binary logs that are either
  used by slaves or have active xid that are not yet committed.

Some implementation notes:

- max-binlog-total-size is by default 0 (no limit).
- max-binlog-total-size can be changed without server restart.
- Binlog file sizes are checked on startup, or if
  max-binlog-total-size is set to a value > 0, not for every log write.
  The total size of all binary logs is cached and dynamically updated
  when updating the binary log on binary log rotation.
- max-binlog-total-size is checked against existing log files during
  serverstart, binlog rotation, FLUSH LOGS, when writing to binary log
  or when max-binlog-total-size changes value.
- Option --slave-connections-needed-for-purge with 1 as default added.
  This allows one to ensure that we do not delete binary logs if there
  is less than 'slave-connections-needed-for-purge' connected.
  Without this option max-binlog-total-size would potentially delete
  binlogs needed by slaves on server startup or when a slave disconnects
  as there are then no connected slaves to protect active binlogs.
- PURGE BINARY LOGS TO ... will be executed as if
  slave-connectitons-needed-for-purge would be zero. In other words
  it will do the purge even if there is no slaves connected. If there
  are connected slaves working on the logs, these will be protected.
- If binary log is on and max-binlog-total_size <> 0 then the status
  variable 'Binlog_disk_use' shows the current size of all old binary
  logs + the state of the current one.
- Removed test of strcmp(log_file_name, log_info.log_file_name) in
  purge_logs_before_date() as this is tested in can_purge_logs()
- To avoid expensive calls of log_in_use() we cache the result for the
  last log that is in use by a slave. Future calls to can_purge_logs()
  for this binary log will be quickly detected and false will be returned
  until a slave starts working on a new log.
- Note that after a binary log rotation caused by max_binlog_size,
  the last log will not be purged directly as it is still in use
  internally. The next binary log write will purge binlogs if needed.

Reviewer:Kristian Nielsen <knielsen@knielsen-hq.org>