When "--export" mariabackup option is used, mariabackup starts the server in
bootstrap mode to generate *.cfg files for the certain innodb tables.
The started instance of the server reads options from the file, pointed
out in "--defaults-file" mariabackup option.

If the server uses the same config file as mariabackup, and binlog is
switched on in that config file, then "mariabackup --prepare --export"
will create binary log files in the server's binary log directory, what
can cause issues.

The fix is to add "--skip-log-bin" in mysld options when the server is
started to generate *.cfg files.

For release builds, do not declare unused variables.

unpack_row(): Omit a debug-only variable from WSREP diagnostic message.

create_wsrep_THD(): Fix -Wmaybe-uninitialized for the PSI_thread_key.

MDEV-20645: Replication consistency is broken as workers miss the error notification from an earlier failed group.

Analysis:
========
In general if there are three groups.
1 - Inserts 32 which fails due to local entry '32' on slave.
2 - Inserts 33
3 - Inserts 34

Each group considers itself as a waiter and it waits for prior group 'waitee'.
This is done in 'register_wait_for_prior_event_group_commit'. If there is no
other parallel group being scheduled then no waitee will be there.

Let us assume 3 groups are being scheduled in parallel.

3-> waits for 2-> waits for->1

'1' upon completion it checks is there any registered subsequent waiter. If
so it wakes up the subsequent waiter with its execution status. This execution
status is stored in wakeup_error.

If '1' failed then it sends corresponding wakeup_error to 2. Then '2' aborts
and it propagates error to '3'.  So all further commits are aborted.  This
mechanism works only when all transactions reach a stage where they are
waiting for their prior commit to complete.

In case of optimistic following scenario occurs.

1,2,3 are scheduled in parallel.

3 - Reaches group_commit_code waits for 2 to complete.
1 - errors out sets stop_on_error_sub_id=1.

When a group execution results in error its corresponding sub_id is set to
'stop_on_error_sub_id'. Any new groups queued for execution will check if
their sub_id is > stop_on_error_sub_id.  If it is true their execution will be
skipped as prior group execution failed.  'skip_event_group=1' will be set.
Since the execution of SQL thread is about to stop we just skip execution of
all the following event groups.  We still do all the normal waiting and wakeup
processing between the event groups as a simple way to ensure that everything
is stopped and cleaned up correctly.

Upon error '1' transaction checks for registered waiters. Since no one is
there it simply goes away.

2 - Starts the execution. It checks do I have a waitee.

Since wait_commit_sub_id == entry->last_committed_sub_id no waitee is set.

Secondly: 'entry->stop_on_error_sub_id' is set by '1'st execution.  Now
'handle_parallel_thread' code checks if the current group 'sub_id' is greater
than the 'sub_id' set within 'stop_on_error_sub_id'.

Since the above is true 'skip_event_group=true' is set.  Simply call
'wait_for_prior_commit' to wakeup all waiters.  Group '2' didn't had any
waitee and its execution is skipped.  Hence its wakeup_error=0.It sends a
positive wakeup signal to '3'. Which commits. This results in a missed
transaction. i.e 33 is missed and 34 is committed.

Fix:
===
When a worker learns that an earlier transaction execution has failed, and it
should not proceed for further execution, it should mark its own execution
status as failed so that it alerts its followers to abort as well.

A syntax error in the mysqld_multi.sh script has been fixed
here + a "--defaults-group-suffix" option has been moved to
the top of the mysqld options list.

The test encryption.innodb-redo-badkey was accidentally disabled
until commit 23657a21 enabled
it recently. Once it was enabled, it started failing randomly.

recv_recover_corrupt_page(): Do not assume that any redo log exists
for the page. A page may be unnecessarily read by read-ahead.
When noting the corruption, reset recv_addr->state to RECV_PROCESSED,
so that even if the same page is re-read again, we will only
decrement recv_sys->n_addrs once.

Spotted by Thirunarayanan Balathandayuthapani.

rw_lock_own(), rw_lock_own_flagged(): Traverse the rw_lock_t::debug_list
only after quickly checking if the thread is holding X-latch or SX-latch.

chkconfig --add and --del [might] invoke /sbin/insserv
and even if chkconfig exists, insserv might not (SLES15).

Ignore chkconfig --del errors - it's a "best effort" cleanup anyway

The test innodb_fts.fulltext_table_evict was only creating 1000 tables
with fulltext indexes, only to check that no tables with fulltext
indexes are being evicted.

The reason why tables containing fulltext indexes cannot be evicted is
that fts_optimize_init() invokes dict_table_prevent_eviction().

For CMAKE_BUILD_TYPE=Debug, the default MYSQL_MAINTAINER_MODE=AUTO
implies -Werror along with other flags in cmake/maintainer.cmake,
which would break the debug builds when CMAKE_CXX_FLAGS include -O2.

This fix includes a backport of 6dd3f240
from MariaDB 10.3.

Test innodb_read_only startup (which will be refused after a crash),
and test also innodb_force_recovery=5, and extract some change buffer
merge statistics. Omit any statistics about delete (purge) buffering,
because purge could happen at any time.

Use the sequence storage engine for populating the table.

Add a test case. MariaDB Server 10.2 is not affected.

A syntax error in the mysqld_multi.sh script has been fixed
here + a "--defaults-group-suffix" option has been moved to
the top of the mysqld options list.

Eliminate one InnoDB table with 128*16384 rows, and use
the sequence engine instead. Also, run everything in a single
transaction, to prevent purge from running concurrently
unnecessarily. (Starting with MariaDB Server 10.3, purge would
reset the DB_TRX_ID after INSERT.)

btr_block_get(): Remove #ifdef around the definition

MDEV-20495 Assertion `precision > 0' failed in decimal_bin_size upon CREATE .. SELECT with zerofilled decimal

Also fixes:

MDEV-20560 Assertion `precision > 0' failed in decimal_bin_size upon SELECT with MOD short unsigned decimal

Changing the way how Item_func_mod calculates its max_length.
It now uses decimal_precision(), decimal_scale() and unsigned_flag
of its arguments, like all other Item_num_op descendants do.

Backporting 273d8eb1 Proper fix for disabling warnings in read_statistics_for_table()

The parameter dup_chk_only was always passed as a constant false.
Remove the parameter and the dead code related to it.

In the function test_if_cheaper_ordering we make a decision if using an index is better than
using filesort for ordering. If we chose to do range access then in test_quick_select we
should make sure that cost for table scan is set to DBL_MAX so that it is not picked.

The unit files made systemd print:

systemd[1]: Started MariaDB 10.3.13 database server (multi-instance).

Let's add the instance name, so starting mariadb@foo.service
makes it print:

systemd[1]: Started MariaDB 10.3.13 database server (multi-instance foo).

"--defaults-group-suffix" must be be given as the first argument on the command-line of mysqld

mysqld_safe --dry-run needs to either call exit or return, depending if
it is being sourced or not, otherise return can lead to the error:

return: can only `return' from a function or sourced script

The original fix suggestion was proposed by FaramosCZ <mschorm@centrum.cz>

* Change the comments in mysql-log-rotate.sh to refer to mysqld, not mysqld_safe
  as that's what most distros are using.
* Change err-log to log-error as err-log is no longer valid.
* Convert tab to space for consistency.

- Enable the test `sphinx.sphinx` which was disabled by MDEV 10986,
  comit ee0094d2
- Add test case to `sphinx.sphinx` to cover host as localhost instead of `127.0.0.1`
- Add result file for single test

There's an annoying bug that prevents a Sphinx table to connect to a searchd using a host name.
So the example table in the documentation https://mariadb.com/kb/en/library/about-sphinxse/#basic-usage that point's to "localhost" actually doesn't work.
After some investigation I found two errors. The first one is a wrong check after the getaddrinfo call. The second is a wrong usage of the returned struct.

Include comment header that describes overrides.

Unit description now includes @VERSION@.

After=syslog.target removed - redunant

Add --basedir=@prefix to prevent /root/.my.cnf lookups. This is
placed after $MYSQLD_OPTIONS in case a user sets a --{no,}default
type options which has to be first in the mysqld arguements.

Additional changes to multi instance (support-files/mariadb@.service.in):
* added @SYSTEMD_EXECSTARTPRE@ / @SYSTEMD_EXECSTARTPOST@
* removed mariadb@bootstrap reference as galera_new_cluster as
  it's a little too proment.
* use_galera_new_cluster.conf updated to override pre/post steps
  to ensure it has no side effects
Signed-off-by: Daniel Black <daniel@linux.vnet.ibm.com>