Extend plugin auth api to support up to 512 bytes in the user names.
Use the API versioning to support old auth plugins too!

          The get_mbr() method shouldn't return the error, rather an invalid MBR
          in this case.

Fixed printing column_get finction.

-Wno-invalid-offsetoff  is a C++ warnng, not C.

Patch by Pavel Ivanov.

During server shutdown, we need to wait for binlog checkpointing to
finish in the binlog background thread before closing the binlog.

This was not done, so we could get assert and failure to finish the
final binlog checkpoint if shutdown happened in the middle.

-Change my_rnd() slightly to make it safer if two threads use it at the same time.
-Avoid some sprintf and strmov in vio.
-Changed thread_count to be automaticly incremented (instead of under LOCK_thread_count).
-Thread cache now uses LOCK_thread_cache instead of LOCK_thread_count.
-Moved delete thd out from LOCK_thread_count.
-Save some mysql_cond_broadcast(&COND_thread_count) calls.
-Removed call to getsockname() during connect.
-Initialize random generator without locks.

Other things:
-Fixed test cases that depends on changes for LOCK_grant
-Added thread_safe_decrement32() and thread_safe_increment32()
-Removed sql_rnd_with_mutex() and get_thread_running()
-In check_table_access() don't lock LOCK_grant if we can resolve the grant with user or db level grants (the normal case).
-Don't use a lock for setting THD->query_id.
-Fixed bug where thd->set_query_id() could be set to same value by multiple threads.

Thanks to Yoshinori Matsunobu for the benchmark of connection speed and to
Domas Mituzas for the inspiration for many of the fixes.


include/violite.h:
  Change desc to a string pointer
mysql-test/suite/perfschema/r/all_instances.result:
  Added new mutex
mysql-test/suite/perfschema/t/func_mutex.test:
  Test for LOCK_system_variables_hash instead of LOCK_grant, as LOCK_grant is not anymore always taken for SELECT's.
mysys/my_gethwaddr.c:
  More DBUG
mysys/my_rnd.c:
  Change my_rnd() slightly to make it safer if two threads use it at the same time.
sql/event_scheduler.cc:
  Changed thread_count to be automically incremented
  Moved some safe things out from LOCK_thread_count.
  Simplify deleting of THD for running thread.
sql/mysqld.cc:
  Changed thread_count to be automically incremented
  Thread cache now uses LOCK_thread_cache instead of LOCK_thread_count
  Added delete_running_thd()
  Moved delete thd out from LOCK_thread_count
  More DBUG
  Only call  mysql_cond_broadcast(&COND_thread_count) if thread_count is 0
  Removed call to getsockname() (old not anymore needed check)
sql/mysqld.h:
  Removed sql_rnd_with_mutex() (not needed anymore)
  Removed not used function get_thread_running()
  Added thread_safe_decrement32() and thread_safe_increment32()
  Simplified dec_thread_running() and inc_thread_running()
  next_query_id() should return the original value for global_query_id, not the next one.
  (Bug introduced with MySQL 5.5 merge).
sql/sql_acl.cc:
  In check_table_access() don't lock LOCK_grant if we can resolve the grant with user or db level grants (the normal case).
sql/sql_class.cc:
  Removed thd_lock_thread_count() and thd_unlock_thread_count()
  Initialize random generator without locks
  Don't use a lock for setting THD->query_id.
  (This is only accessed by thread owning the THD)
sql/sql_class.h:
  Don't use a lock for setting THD->query_id.
sql/sql_insert.cc:
  Changed thread_count to be automically incremented
sql/sql_parse.cc:
  Changed thread_count to be automically incremented
  Fixed bug where thd->set_query_id() could be set to same value by multiple threads.
vio/vio.c:
  Don't generate 'desc' with sprintf/strmov. Assign a pointer instead.
  (Good enough as this is just for debugging)

        The Geometry::get_mbr() function can return an error on
        a bad data. We have to check for that and act respectively.

- Set MI_INFO::external_ref for MyISAM tables that are parts of myisamMRG table.

./mtr --suite=main,plugins
will work on all branches.

MDEV-4293 Valgrind warnings (Conditional jump or move depends on uninitialised value) in remove_eq_conds on time functions with NULL argument

val_int() is expected to return 0 for NULL's

-Change my_rnd() slightly to make it safer if two threads use it at the same time.
-Avoid some sprintf and strmov in vio.
-Changed thread_count to be automically incremented (instead of under LOCK_thread_count).
-Thread cache now uses LOCK_thread_cache instead of LOCK_thread_count.
-Moved delete thd out from LOCK_thread_count.
-Save some mysql_cond_broadcast(&COND_thread_count) calls.
-Removed call to getsockname() during connect.
-Initialize random generator without locks.

Other things:
-Added thread_safe_decrement32() and thread_safe_increment32()
-Removed sql_rnd_with_mutex() and get_thread_running()

Thanks to Yoshinori Matsunobu for the benchmark of connection speed and to
Domas Mituzas for the inspiration for many of the fixes.
 

include/violite.h:
  Change desc to a string pointer
mysql-test/suite/perfschema/r/all_instances.result:
  Added new mutex
mysys/my_rnd.c:
  Change my_rnd() slightly to make it safer if two threads use it at the same time.
sql/event_scheduler.cc:
  Changed thread_count to be automically incremented
  Moved some safe things out from LOCK_thread_count.
  Simplify deleting of THD for running thread.
sql/mysqld.cc:
  Changed thread_count to be automically incremented
  Thread cache now uses LOCK_thread_cache instead of LOCK_thread_count
  Added delete_running_thd()
  Moved delete thd out from LOCK_thread_count
  More DBUG_ENTER
  Only call  mysql_cond_broadcast(&COND_thread_count) if thread_count is 0
  Removed call to getsockname() (old not anymore needed check)
sql/mysqld.h:
  Removed sql_rnd_with_mutex() (not needed anymore)
  Removed not used function get_thread_running()
  Added thread_safe_decrement32() and thread_safe_increment32()
  Simplified dec_thread_running() and inc_thread_running()
sql/sql_class.cc:
  Removed thd_lock_thread_count() and thd_unlock_thread_count()
  Initialize random generator without locks
sql/sql_insert.cc:
  Changed thread_count to be automically incremented
sql/sql_parse.cc:
  Changed thread_count to be automically incremented
vio/vio.c:
  Don't generate 'desc' with sprintf/strmov. Assign a pointer instead.
  (Good enough as this is just for debugging)

(in INFORMATION_SCHEMA).

  
The reason is the limitation of ReadConsole() API, it returns error if handle to redirected  input  is used.
  
 The fix is to use a  handle returned by CreateFile("CONIN$",...), rather than GetStdHandle(STD_HANDLE_INPUT) to get the true console handle.

The output of mysqlbinlog (with "-v --base64-output=DECODE-ROWS" flags) can not always be read or parsed correctly
when string columns contain single-quotes or backslash characters.

The fix for this bug is to escape single-quote and backslash characters on output, so that the result is both more
readable and more easily parse-able.

Note that this is just for comments, so it doesn't affect the replication.

sql/log_event.cc:
  Escape \ and ' properly for mysqlbin user comments.

        Need to check if the number of points is 0 for the polygon.

        Forgotten DBUG_ASSERT should be replaced with the 'return error'.

Item_default_value inherited form Item_field so should create temporary table field similary.

    Additional fixes for possible overflows in length-related
    calculations in 'spatial' implementations.
    Checks added to the ::get_data_size() methods.
    max_n_points decreased to occupy less 2G size. An
    object of that size is practically inoperable anyway.

Item_func_make_set wasn't taking into account the first argument when
calculating maybe_null.

sql/item_strfunc.cc:
  rewrite Item_func_make_set, removing separate storage of the first argument
sql/item_strfunc.h:
  rewrite Item_func_make_set, removing separate storage of the first argument

  
with decimals=NOT_FIXED_DEC it is possible to have 'decimals' larger
than 'max_length', it's not an error for temporal functions.
  
But when Item_func_numhybrid converts the value to DECIMAL_RESULT,
it must limit 'decimals' to be a valid scale of a decimal number.

AVG() returns a double, its max_length is reasonably
limited by a double number length, even if the argument
is many Kbytes long.

STRAIGHT_JOIN couldn't be combined with NATURAL or USING(), 
INNER JOIN not with NATURAL (MDEV-4271, MySQL Bug #35268)

Separate rules existed for "natural" (non-outer) joins and
for STRAIGHT_JOIN, with the only difference code wise being 
that with STRAIGHT_JOIN the "straight" property of the right
side table was set before calling the appropriate add_...()
function.

The "natural_join" parser rule has now been extended to also
accept STRAIGHT_JOIN, and the rule result value is set to
1 for straight joins, 0 otherwise, so acting as a "straight"
flag that can directly be assigned to the "straight" property
of the right side table.

The rule parsing NATURAL JOIN was hard coded to accept just
this keyword combination, without support for either 
STRAIGHT_JOIN or the optional INNER.

The "natural_join" rule has now been split up in an inner
"inner_join" rule that matches the JOIN, INNER JOIN and
STRAIGHT_JOIN cases while "natural_join" also matches
CROSS JOIN. 

The NATURAL rule has been changed to accept "inner_join"
instead of just JOIN, so now NATURAL STRAIGHT_JOIN and
NATURAL INNER JOIN also work as expected.

As a side effect the removal of the duplciated rules
for STRAIGHT_JOIN handling has reduced the shift/reduce
conflict count by one.

mysql-test/r/join.result:
  Added new test cases
mysql-test/t/join.test:
  Added new test cases
sql/sql_yacc.yy:
  The "natural_join" parser rule was extended to also accept STRAIGHT_JOIN
  NATURAL STRAIGHT_JOIN and NATURAL INNER JOIN also now work as expected

Flip the switch and create Item_cache based on the argument's cmp_type, not argument's result_type().
Fix subselect_engine to calculate cmp_type correctly

sql/item_subselect.h:
  mdev:4284

MDEV-4281 Assertion `maybe_null && item->null_value' fails in make_sortkey on CASE with different return types, GROUP_CONCAT, GROUP BY

Fix Item::get_date() to mark the item NULL when returning an error.

Incorrect NULL value handling in Item_func_conv_charset fixed.

mysql-test/r/keywords.result:
  Test that option works as table/column/variable
mysql-test/suite/funcs_1/r/storedproc.result:
  OPTION is now a valid identifier
mysql-test/suite/funcs_1/t/storedproc.test:
  OPTION is now a valid identifier
mysql-test/t/keywords.test:
  Test that option works as table/column/variable
sql/sql_yacc.yy:
  OPTION is now a valid identifier

  Adding an include file which checks whether long names are supported

get_datetime_value() should not double-cache its own Item_cache_temporal items,
but it *should* cache other Item_cache items, such as Item_cache_str.

sql/item.h:
  shortcut, to avoid going through the switch in Item::cmp_type()
sql/item_cmpfunc.cc:
  even if the item is Item_cache_str - it still needs to be converted and cached.
sql/item_timefunc.h:
  all descendants of Item_temporal_func always have cmp_type==TIME_RESULT.
  Even Item_date_add_interval, that might have field_type == MYSQL_TYPE_STRING.