In fsp_path_to_space_name(), we would access a byte right before
the start of the string, tripping AddressSanitizer.

This reverts commit d87006a1
and commit a7634281.

Avoid character set conversion for numeric data in this scenario:

SET NAMES utf8;
CREATE OR REPLACE TABLE t1 (a INT);
INSERT INTO t1 VALUES (1);
SELECT a FROM t1;

- Renaming this virtual method store() to store_str():
    store(const char *str, size_t length, CHARSET_INFO *src_cs, CHARSET_INFO *dst_cs)
  We'll be adding more variants of store*() soon. This change will help to avoid
  ambiguities during overloading.

- Adding a helper method store_ident().

- Renaming store_str(const LEX_CSTRING &s...) to store_lex_cstring(),
  to avoid ambiguties during overloading.

- Adding a helper method store() for backward compatibility, to avoid a lot of
  changes in the code now. But eventually we should replace store() to
  non-ambiguius methods store_str() or store_ident().

- Adding a helper method Protocol::needs_conversion() and reusing it
  in two places.

This version is not optimized yet. It could have bugs because I didn't
check it with unit tests. Also, std::char_traits are not really supported.
So, now it's not possible to create f.ex. a case insensitive string_view.

fil_path_to_space_name(): renamed, moved to another file
and refactored to use string_view

We must prevent InnoDB purge from acquiring MDL on the tables.
Since MDEV-12288, INSERT is generating work for purge.

The only InnoDB change between MySQL 5.7.30 and MySQL 5.7.31
that is applicable to MariaDB Server was applied in
commit 8d061996 (MDEV-23161).

The only InnoDB changes between Percona XtraDB Server 5.6.47-87.0
and 5.6.48-88.0 are related to InnoDB changes between MySQL 5.6.47
and MySQL 5.6.48, which we had already applied.

There were no InnoDB changes between MySQL 5.6.48 and MySQL 5.6.49.

This issue was originally reported by Fungo Wang, along with a fix, as
MySQL Bug #98990.

His suggested fix was applied as part of
mysql/mysql-server@a003fc373d1adb3ccea353b5d7d83f6c4c552383
and released in MySQL 5.7.31.

i_s_metrics_fill(): Add the missing call to Field::set_notnull(),
and simplify some code.

- i_s_fts_index_cache_fill() should take shared lock of fts cache
before accessing index cache to avoid reading stale data.

- Problem is that test case creates iblogfile* files. So existing
ibdata pages could point to future LSN. Fix is that taking the
backup of data before iblogfile* creation and apply it before
exiting the test case.

MDEV-22890 DEADLOCK of threads detected: row0sel.cc S-LOCK / btr0cur.cc S-LOCK / row0quiesce.cc X-LOCK

Problem:
=======
- Read operations are always allowed to hold a secondary index leaf
latch and then look up the corresponding clustered index record.
Flush table operation acquires secondary index latch while holding
a clustered index latch. It leads to deadlock violation.

Fix:
====
- Flush table operation should acquire secondary index before taking
clustered index to avoid deadlock violation with select operation.

Only install wsrep scripts and links if WSREP_ON is actually set

MDEV-22463: Element_type &Bounds_checked_array<Item *>::operator[](size_t) [Element_type = Item *]: Assertion `n < m_size' failed.

Allocate space for fields inside the window function (arguments, PARTITION BY and ORDER BY clause)
in the ref pointer array. All fields inside the window function are part of the temporary
table that is required for the window function computation.

buf_pool_t::page_hash_table::create(): Use aligned_malloc()
for the hash array, to get the page_hash_latch aligned on the
same L1 data cache line as the data that it is protecting.

This form of corruption was only reproduced on MariaDB 10.5.4
after the MDEV-22867 fix was applied in
commit 43120009.

While we do not know how to reproduce this corruption in
MariaDB 10.4, we are applying the code fix without a test case.

btr_cur_pessimistic_update(): Invoke btr_set_instant() if needed.

MDEV-22058: Assertion `!is_set() || (m_status == DA_OK_BULK && is_bulk_op())' failed in Diagnostics_area::set_ok_status

Error state is not stored in check_and_do_in_subquery_rewrites() when there is
illegal combination of optimizer switches. So all the functions eventually
return false. Thus the assetion failure.

- Add 'libboost-all-dev' and 'libreadline-gplv2-dev' as they were was found
  to be a compulsory build dependency for columnstore plugin.
- Add 'expect' as run-time dependencey for columnstore plugin as scripts
  use it:
    usr/bin/mcs_module_installer.sh: #!/usr/bin/expect
    usr/bin/remote_command.sh: #!/usr/bin/expect
    usr/bin/remote_command_verify.sh: #!/usr/bin/expect
    usr/bin/remote_scp_get.sh: #!/usr/bin/expect
    usr/bin/remote_scp_put.sh: #!/usr/bin/expect
    usr/bin/rsync.sh: #!/usr/bin/expect
- Properly define depends on Python. No Python 2 support needs to be
  considered, Python 3 has been around long enough. Fixes Lintian errors
    E: mariadb-plugin-columnstore: python-script-but-no-python-dep
    usr/bin/mcs-loadbrm.py #!python
    E: mariadb-plugin-columnstore: python-script-but-no-python-dep
    usr/bin/mcs-start-storagemanager.py #!python
- Partially revert undocumented and thus unjustified changes in commits
  d69a79da63287089efdc5f90a11ecd66ce55b471 and
  c0565666cfe6528b76bc53ce50d3690d13c92cf6.
- Trigger ldconfig, otherwise Lintian complains:
    E: mariadb-plugin-columnstore: package-must-activate-ldconfig-trigger
    usr/lib/x86_64-linux-gnu/libwriteengineredistribute.so
- Update postinst to be compatible with new server binary mariadbd name.
- Properly detect systemd or fallback to sysv init in postrm script.
- Only attempt to build ColumnStore on amd64 and i386. Test builds on
  Launchpad.net showed the CMake plugin configure step will prevent even
  attempts to build on other platforms.
- Clean up and unify cmake build command in debian/rules.
- Explicitly list files not installed.
- Run 'wrap-and-sort -a -v'.
- Truncate build logs on Salsa-CI to keep under 4 MB. This is now needed
  as the ColumnStore build is so verbose.
  See https://jira.mariadb.org/browse/MCOL-4111.
- Update Travis-CI dependencies to match new debian/control.

The auth_pam_tool that is executed from pam_auth() can be still
not finished by the time we do the waitpid() there.
As we use WNOHANG option for the waitpid(), it didn't wait and
left the zombie process. So let's do the loop of waitpid() with the
limited number of sleeps.

The client can only find out if the server has disconnected when it tries to
read or send something. If the server gets disconnected before
send_client_reply_packet(), the client will try sending authentication
information but it will fail. But, if the client is fast enough to send
autentication information before disconnecting, it will notice that when
reading the ok packet. So the client can fail on read or on write.
It is unpredictable because, the process are unsynchronized and this
could happen in any order.

Reject queries that have aggregate functions with UNION as these
are not allowed by standard.

../sql/sql_class.cc: In constructor ‘start_new_trans::start_new_trans(THD*)’:
../include/m_string.h:61:49: error: ‘void* memset(void*, int, size_t)’ clearing an object of non-trivial type ‘struct Ha_data’; use assignment or value-initialization instead [-Werror=class-memaccess]
   61 | # define bzero(A,B)             memset((A),0,(B))
      |                                                 ^
../sql/sql_class.cc:5805:3: note: in expansion of macro ‘bzero’
 5805 |   bzero(thd->ha_data, sizeof(thd->ha_data));
      |   ^~~~~
In file included from ../sql/sql_class.cc:33:
../sql/sql_class.h:2003:8: note: ‘struct Ha_data’ declared here
 2003 | struct Ha_data
      |        ^~~~~~~

In mi_check_index_tuple(), when rowid filter check returns
CHECK_OUT_OF_RANGE, set info->lastpos= HA_OFFSET_ERROR, like
it is done above for the ICP check.

Check if we really need the mariadb.sys user