SHOW ENGINE INNODB STATUS and SHOW GLOBAL VARIABLES were blocking on the locks used
to access the history length in MDEV-29141. While the reason for the blockage
was elsewhere, we should make these monitoring commands less blocking as there
is a trx_sys.history_size_approx function that can be used.

SHOW ENGINE INNODB STATUS and SHOW GLOBAL STATUS LIKE
'innodb_history_list_length' and Innodb Monitors can use
trx_sys.history_size_approx().

- Remove the FILE_MODIFY message in backup_file_op()

This commit is a fixup for MDEV-28762

Analysis: Some recursive json functions dont check for stack control
Fix: Add check_stack_overrun(). The last argument is NULL because it is not
used

Get rid of BTR_ESTIMATE and btr_cur_t::path_arr.

Before the fix btr_estimate_n_rows_in_range_low() used two
btr_cur_search_to_nth_level() calls to create two arrays of tree path,
the array per border. And then it tried to estimate the number of rows
diving level-by-level with the array elements. As the path pages are
unlatched during the arrays iterating, the tree could be modified, the
estimation function called itself until the number of attempts exceed.

After the fix the estimation happens during search process. Roughly, the
algorithm is the following. Dive in the left page, then if there are pages
between left and right ones, read a few pages to the right, if the right
page is reached, fetch it and count the exact number of rows, otherwise
count the estimated number of rows, and fetch the right page.

The latching order corresponds to WL#6326 rules, i.e.:

(2.1) [same as (1.1)]: Page latches must be acquired in descending order
of tree level.

(2.2) When acquiring a node pointer page latch at level L, we must hold
the left sibling page latch (at level L) or some ancestor latch
(at level>L).

When we dive to the level down, the parent page is unlatched only after
the the current level page is latched. When we estimate the number of rows
on some level, we latch the left border, then fetch the next page, and
then fetch the next page unlatching the previous page after the current
page is latched until the right border is reached. I.e. the left sibling
is always latched when we acquire page latch on the same level. When we
reach the right border, the current page is unlatched, and then the right
border is latched. Following to (2.2) rule, we can do this because the
right border's parent is latched.

- Remove the FILE_MODIFY message from mariabackup which was
displaying the list of file names which were modified since
the previous checkpoint.

It is legal that open table can leave unopened tables in SP and other
parts of the code shoud expect it.

Analysis: Some recursive json functions dont check for stack control
Fix: Add check_stack_overrun(). The last argument is NULL because it is not
used

In previous versions it was stated that MDEV-25968 was causing other
jobs in the pipeline to fail if not run with "-j 2" but this bug was not
affecting fedora-ninja. This is still true for the public gitlab runners.
However, running the fedora-ninja job on custom runners with more processors
without the "-j 2" flag will cause the compiler to crash.

When running the build with 2,4,8,16,32 threads, build times were
consistent indicating that the typical bottleneck is I/O and not CPU
cores. Therefore, "-j 2" is not a big drawback and it was chosen in
order to remain consistent with the other builds affected by MDEV-25968.

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.

Rewrite queries to not use the deprecated syntax and avoid warnings.

Close handlers in THD::drop_temporary_table.

Step 1 in handling InnoDB AIO assertions better is to get
more detail of the cases of error.

This doesn't resolve MDEV-27593, but increases the level
of information in the assertion.

Fix the side effect of MDEV-4750 (reenabling innodb_stats_persistent),
so that sporadic MDL acquisition for this table does not interfere with
SELECT from information_schema.metadata_lock_info

mysql_json: GAMMA -> STABLE

Problem:
=======
ALTER TABLE in InnoDB fails to detect duplicate entries
for the unique index when the character set or collation of
an indexed column is changed in such a way that the character
encoding is compatible with the old table definition.
In this case, any secondary indexes on the changed columns
would be rebuilt (DROP INDEX, ADD INDEX).

Solution:
========
During ALTER TABLE, InnoDB keeps track of columns whose collation
changed, and will fill in the correct metadata when sorting the
index records, or applying changes from concurrent DML.
This metadata will be allocated in the dict_index_t::heap of
the being-created secondary indexes.

The fix was developed by Thirunarayanan Balathandayuthapani
and simplified by me.

Depending on OpenSSL version, and at least in 3.0.3, the client-side socket
timeout is reported as generic error (SSL_ERROR_SYSCALL), losing further
details (both errno and GetLastError() return 0). This results in client
reporting "Unknown OpenSSL error" 2026, instead of another generic
"Lost connection to server during query" 2013

Adjusted test case.

Part of MDEV-29000

OpenSSL 3.0.0+ does not support EVP_MD_CTX_FLAG_NON_FIPS_ALLOW any longer.
In OpenSSL 1.1.1 the non FIPS allowed flag is context specific, while
in 3.0.0+ it is a different EVP_MD provider.

Fixes #2010

part of MDEV-29000

This reverts commit c9beef43, because
we have OpenSSL 3.0 support here.

part of MDEV-29000

Summary of changes

- MD_CTX_SIZE is increased

- EVP_CIPHER_CTX_buf_noconst(ctx) does not work anymore, points
  to nobody knows where. The assumption made previously was that
  (since the function does not seem to be documented)
  was that it points to the last partial source block.
  Add own partial block buffer for NOPAD encryption instead

- SECLEVEL in CipherString in openssl.cnf
  had been downgraded to 0, from 1, to make TLSv1.0 and TLSv1.1 possible
   (according to https://github.com/openssl/openssl/blob/openssl-3.0.0/NEWS.md
   even though the manual for SSL_CTX_get_security_level claims that it
   should not be necessary)

- Workaround Ssl_cipher_list issue, it now returns TLSv1.3 ciphers,
  in addition to what was set in --ssl-cipher

- ctx_buf buffer now must be aligned to 16 bytes with openssl(
  previously with WolfSSL only), ot crashes will happen

- updated aes-t , to be better debuggable
  using function, rather than a huge multiline macro
  added test that does "nopad" encryption piece-wise, to test
  replacement of EVP_CIPHER_CTX_buf_noconst

part of MDEV-29000

ha_innobase::check_if_supported_inplace_alter(): Refuse to change the
collation of a column that would become or remain indexed as part of
the ALTER TABLE operation.

In MariaDB Server 10.6, we will allow this type of operation;
that fix depends on MDEV-15250.

Add limited support for building embedded library (DLL only).

- Fixes 29e8c154 (MDEV-25857)
Review by: <@mariadb.com>

Starting with 10.5, InnoDB crash recovery tests seem to time out
more easily under Valgrind, which emulates multiple threads by
interleaving them in a single operating system thread.

These tests will still be covered by
AddressSanitizer and MemorySanitizer.

Remove the affected assert.
Wait for all AIO_buffer_cache::release_buffer() to finish before
AIO_buffer_cache::clear().

- InnoDB mistakenly identifies the non-unique FTS_DOC_ID index as
FTS_DOC_ID_INDEX while loading the table. dict_load_indexes()
should check whether the index is unique before assigning
fts_doc_id_index

Before version 10, GCC would think that a right shift of an
unsigned char returns int. Let us explicitly cast that back,
to silence a bogus -Wconversion warning.

Also, refactor trx_i_s_common_fill_table() to remove dead code.

Warnings about yynerrs in Bison-generated yyparse() will remain for now.

K&R style function definitions are deprecated in all versions of C
and not supported in C2x.

MDEV-28919 Assertion `(((core_null) + 7) >> 3) == oindex.n_core_null_bytes || !not_redundant()' failed

- In case of discarded tablespace, InnoDB can't read the root page to
assign the n_core_null_bytes. Consecutive instant DDL fails because
of non-matching n_core_null_bytes.

fil_space_t::acquire_low(): Introduce a parameter that specifies
which flags should be avoided. At all times, referenced() must not
be incremented if the STOPPING flag is set. When fil_system.mutex
is not being held by the current thread, the reference must not be
incremented if the CLOSING flag is set (unless NEEDS_FSYNC is set,
in fil_space_t::flush()).

fil_space_t::acquire(): Invoke acquire_low(STOPPING | CLOSING).
In this way, the reference count cannot be incremented after
fil_space_t::try_to_close() invoked fil_space_t::set_closing().

If the CLOSING flag was set, we must retry acquire_low() after
acquiring fil_system.mutex.

fil_space_t::prepare_acquired(): Replaces prepare(true).

fil_space_t::acquire_and_prepare(): Replaces prepare().
This basically retries fil_space_t::acquire() after
acquiring fil_system.mutex.

MDEV-28806 Assertion `flag == 1' failure in row_build_index_entry_low upon concurrent ALTER and UPDATE

- During online ADD INDEX, InnoDB was incorrectly writing log for an
UPDATE that does not affect the being-created index.

- Redundant InnoDB table fails to set the flags2 while loading
the table. It leads to "Upgrade index name failure" during alter
operation. InnoDB should set the flags2 to FTS_AUX_HEX_NAME when
fts is being loaded