modified:   storage/connect/CMakeLists.txt

- Continue BSON development
  modified:   storage/connect/bson.cpp
  modified:   storage/connect/bson.h
  modified:   storage/connect/bsonudf.cpp
  modified:   storage/connect/bsonudf.h
  added:      storage/connect/mysql-test/connect/r/bson_udf.result
  added:      storage/connect/mysql-test/connect/t/bson_udf.inc
  added:      storage/connect/mysql-test/connect/t/bson_udf.test
  added:      storage/connect/mysql-test/connect/t/bson_udf2.inc

  modified:   storage/connect/CMakeLists.txt
  modified:   storage/connect/bson.cpp
  modified:   storage/connect/bson.h
  modified:   storage/connect/bsonudf.cpp
  modified:   storage/connect/bsonudf.h
  modified:   storage/connect/global.h
  modified:   storage/connect/json.cpp
  modified:   storage/connect/jsonudf.cpp
  modified:   storage/connect/mysql-test/connect/disabled.def
  modified:   storage/connect/mysql-test/connect/t/mongo_test.inc
  modified:   storage/connect/plugutil.cpp
  modified:   storage/connect/tabbson.cpp
  modified:   storage/connect/tabjson.cpp

  Occuring when inserting more than one line in one statement.
  modified:   storage/connect/json.cpp

- Fix a wrong if statement
  modified:   storage/connect/tabjson.cpp

- Continue BSON implementation
  modified:   storage/connect/bson.cpp
  modified:   storage/connect/bson.h
  modified:   storage/connect/filamtxt.cpp
  modified:   storage/connect/filamtxt.h
  modified:   storage/connect/tabbson.cpp
  modified:   storage/connect/tabbson.h

- No need anymore
  deleted:    storage/connect/mysql-test/connect/r/bson.result
  deleted:    storage/connect/mysql-test/connect/t/bson.test

  modified:   storage/connect/jsonudf.cpp
  modified:   storage/connect/jsonudf.h

- Fix compile error (Force_Bson was not conditional by BSON_SUPPORT)
  modified:   storage/connect/ha_connect.cc

- Continue Bjson implementation
  modified:   storage/connect/block.h
  modified:   storage/connect/bson.cpp
  modified:   storage/connect/bson.h
  modified:   storage/connect/bsonudf.cpp
  modified:   storage/connect/bsonudf.h
  modified:   storage/connect/plugutil.cpp
  modified:   storage/connect/tabbson.cpp
  modified:   storage/connect/tabjson.cpp

- Typo
  deleted:    storage/connect/Header.h

  modified:   storage/connect/bson.cpp
  modified:   storage/connect/bson.h
  modified:   storage/connect/bsonudf.cpp
  modified:   storage/connect/cmgfam.cpp
  modified:   storage/connect/cmgfam.h
  modified:   storage/connect/ha_connect.cc
  modified:   storage/connect/jmgfam.cpp
  modified:   storage/connect/jmgfam.h
  modified:   storage/connect/jmgoconn.cpp
  modified:   storage/connect/mycat.cc
  modified:   storage/connect/tabbson.cpp
  modified:   storage/connect/tabjson.cpp

  (and continue BSON implementatio)
  modified:   storage/connect/bson.cpp
  modified:   storage/connect/bson.h
  modified:   storage/connect/bsonudf.cpp
  modified:   storage/connect/connect.cc
  modified:   storage/connect/global.h
  modified:   storage/connect/ha_connect.cc
  modified:   storage/connect/jsonudf.cpp
  modified:   storage/connect/mycat.cc
  modified:   storage/connect/plgdbsem.h
  modified:   storage/connect/plugutil.cpp
  modified:   storage/connect/tabjson.cpp
  modified:   storage/connect/tabjson.h
  modified:   storage/connect/user_connect.cc

- Desesperatly trying to fix xml.test failure
  modified:   storage/connect/mysql-test/connect/r/xml.result

  modified:   storage/connect/bson.cpp
  modified:   storage/connect/bson.h
  modified:   storage/connect/bsonudf.cpp
  modified:   storage/connect/bsonudf.h
  modified:   storage/connect/jsonudf.cpp

Reviewer: Brad Smith

The fix of MDEV-23456 (commit b1009ae5)
introduced a livelock between page flushing and a thread that is
executing buf_page_create().

buf_page_create(): If the current mini-transaction is holding
an exclusive latch on the page, do not attempt to acquire another
one, and do not care about any I/O fix.

mtr_t::have_x_latch(): Replaces mtr_t::get_fix_count().

dyn_buf_t::for_each_block(const Functor&) const: A new variant.

rw_lock_own(): Add a const qualifier.

Reviewed by: Thirunarayanan Balathandayuthapani

Due to a premature cleanup of the unit that specified a recursive CTE
used in the second operand of union the server fell into an infinite
loop in the reported test case. In other cases this premature cleanup
could cause other problems.
The bug is the result of a not quite correct fix for MDEV-17024. The
unit that specifies a recursive CTE has to be cleaned only after the
cleanup of the last external reference to this CTE. It means that
cleanups of the unit triggered not by the cleanup of a external
reference to the CTE must be blocked.
Usage of local table chains in selects to get external references to
recursive CTEs was not correct either because of possible merges of
some selects.

Also fixed a minor bug in st_select_lex::set_explain_type() that caused
typing 'RECURSIVE UNION' instead of 'UNION' in EXPLAIN output for external
references to a recursive CTE.

Analysis:
========
Writes to 'rli->log_space_total' needs to be synchronized, otherwise both
SQL_THREAD and IO_THREAD can try to modify the variable simultaneously
resulting in incorrect rli->log_space_total.  In the current test scenario
SQL_THREAD is trying to decrement 'rli->log_space_total' in 'purge_first_log'
and IO_THREAD is trying to increment the 'rli->log_space_total' in
'queue_event' simultaneously. Hence test occasionally fails with  result
mismatch.

Fix:
===
Convert 'rli->log_space_total' variable to atomic type.