trx_undo_rseg_free(): Revert an inadvertent change that was done
as part of the merge a42c80bd

- During shutdown, InnoDB fts fails to update synced doc id
when there is only one doc id about to sync. While starting
the server, InnoDB fetches the already synced doc id from
config table. In the subsequent sync operation, InnoDB fails
with DB_DUPLICATE_KEY error.

In commit 244fdc43 (MDEV-29438)
we made sure that if the preceding record is the page infimum record,
no more than 8 bytes will be read from it. But, if the data payload of
the being-inserted record is less than 8 bytes (this can happen in
secondary indexes), we must not compare all 8 bytes.

This was caught by a failure of the test gcol.innodb_virtual_basic
under MemorySanitizer and some builds with AddressSanitizer.

- This is caused by commit 1bd681c8(MDEV-25506)
InnoDB removes the index from the table object before freeing the
leaf and non-leaf segments.

The resources like uring in MariaDB aren't intended for spawned
processes so we restrict access using the io_uring_ring_dontfork
liburing library call.

This bug was found in MariaDB Server 10.6 thanks to the
OPT_PAGE_CHECKSUM record that was implemented
in commit 4179f93d for catching
this type of recovery failures.

page_cur_insert_rec_low(): If the previous record is the page infimum,
correctly limit the end of the record. We do not want to copy data from
the header of the page supremum. This omission caused the incorrect
recovery of DB_TRX_ID in an instant ALTER TABLE metadata record, because
part of the DB_TRX_ID was incorrectly copied from the n_owned of the
page supremum, which in recovery would be updated after the copying,
but in normal operation would already have been updated at the time the
common prefix was being determined.

log_phys_t::apply(): If a data page is found to be corrupted, do not
flag the log corrupted but instead return a new status APPLIED_CORRUPTED
so that the caller may discard all log for this page. We do not want
the recovery of unrelated pages to fail in recv_recover_page().

No test case is included, because the known test case would only work
in 10.6, and even after this fix, it would trigger another bug in
instant ALTER TABLE crash recovery.

The replication unsafe warning's pattern gets corrected in the
punctuation part.

MDEV-28530: Revoking privileges from a non-existing user on a master breaks replication on the slave in the presence of replication filters

Problem:
========
Replication can break while applying a query log event if its
respective command errors on the primary, but is ignored by the
replication filter within Grant_tables on the replica. The bug
reported by MDEV-28530 shows this with REVOKE ALL PRIVILEGES using a
non-existent user. The primary will binlog the REVOKE command with
an error code, and the replica will think the command executed with
success because the replication filter will ignore the command while
accessing the Grant_tables classes. When the replica performs an
error check, it sees the difference between the error codes, and
replication breaks.

Solution:
========
If the replication filter check done by Grant_tables logic ignores
the tables, reset thd->slave_expected_error to 0 so that
Query_log_event::do_apply_event() can be made aware that the
underlying query was ignored when it compares errors.

Note that this bug also effects DROP USER if not all users exist
in the provided list, and the patch fixes and tests this case.

Reviewed By:
============
andrei.elkin@mariadb.com

These files are currently not being used nor compiled in MariaDB. The
use of large lists of 'case' statements in these source files are also
not a great way to represent translated strings. This git history can
be referred to when a better translation interface can be implemented
in the future.

Therefore, these files can be removed to cleanup the MariaDB codebase.

All new code of the whole pull request, including one or several files
that are either new files or modified ones, are contributed under the
BSD-new license. I am contributing on behalf of my employer
Amazon Web Services, Inc.

- During rollback of DDL, InnoDB should copy the collation
changed column into the index heap

Spider converts HA_READ_KEY_EXACT to the equality (=) in the
function spider_db_append_key_where_internal() but the conversion
is not necessarily correct for tables with prefix indices.

We fix the bug by converting HA_READ_KEY_EXACT to 'LIKE "foo%"' when
a target key is a prefix key. The fix is partly inspired by FEDERATED.
See ha_federated::create_where_from_key() for more details.

btr_validate_level(): Invoke mtr.commit() after a failure.
This omission was introduced in
commit 0b47c126 (MDEV-13542).

If multiple threads invoke buf_page_get_low() on a ROW_FORMAT=COMPRESSED
page that does not reside in the buffer pool, then one of the threads
will end up acquiring an exclusive page latch (the "if" statement
right before the new wait_for_unzip: label) and other threads will
end up waiting for a shared latch while holding a buffer-fix.
The exclusive latch holder would then wait for the buffer-fixes to
be released while the buffer-fix holders are waiting for the shared latch.

buf_page_get_low(): Prevent the hang that was introduced
in commit 9436c778 (MDEV-27058),
by releasing the buffer-fix, sleeping some time, and retrying the
page lookup.

recv_sys_t::free_corrupted_page(): Identify the corrupted page in
an error or warning message.

buf_page_free(): Just in case, register the page as modified.
This should already have been done in mtr_t::free() as part of
fseg_free_page_low().

mtr_t::memo_push(): Simplify a condition, so that when invoked
with MTR_MEMO_PAGE_X_MODIFY, we will do the right thing.

fseg_free_page_low(): Remove an accidentally added return statement
that prevented mtr_t::free() from being called. This fixes a regression
that was introduced in
commit 0b47c126 (MDEV-13542).

Making changes to wsrep_mysqld.h causes large parts of server code to
be recompiled. The reason is that wsrep_mysqld.h is included by
sql_class.h, even tough very little of wsrep_mysqld.h is needed in
sql_class.h. This commit introduces a new header file, wsrep_on.h,
which is meant to be included from sql_class.h, and contains only
macros and variable declarations used to determine whether wsrep is
enabled.
Also, header wsrep.h should only contain definitions that are also
used outside of sql/. Therefore, move WSREP_TO_ISOLATION* and
WSREP_SYNC_WAIT macros to wsrep_mysqld.h.
Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>

Because of a define error the wrong value was being returned.

Regression in MDEV-28243

Fixes: 607f9874679c3e4ef7edcd2c9d80120051af73cc

Thanks to references from Brad Smith, BSDs use getmntinfo as
a system call for mounted filesystems.

Most BSDs return statfs structures, (and we use OSX's statfs64),
but NetBSD uses a statvfs structure.

Simplify Linux getmntent_r to just use getmntent.

AIX uses getmntent.

An attempt at writing Solaris compatibility with
a small bit of HPUX compatibility was made based on man page
entries only. Fixes welcome.

statvfs structures now use f_bsize for consistency with statfs

Test case adjusted as PATH_MAX is OS defined (e.g. 1023 on AIX)

Fixes: 0ee5cf83

also fixes:

MDEV-27818: Disk plugin does not show zpool mounted devices

This is because zpool mounted point don't begin with /.

Due to the proliferation of multiple filesystem types since this
was written, we restrict the entries listed in the disks plugin
to excude:
* read only mount points (no point monitoring, and
  includes squash, snaps, sysfs, procfs, cgroups...)
* mount points that aren't directories (excludes /etc/hostname and
  similar mounts in containers). (getmntent (Linux/AIX) only)
* exclude systems where there is no capacity listed (excludes various
  virtual filesystem types).

Reviewer: Sergei Golubchik