mysql-test/r/servers.result:
  Added test case for MDEV-4594.
mysql-test/t/servers.test:
  Added test case for MDEV-4594.
sql/mysqld.cc:
  Move servers_init() call to init_server_components(), so it is called
  for embedded as well.
  
  Call servers_free() even if NO_EMBEDDED_ACCESS_CHECKS defined (because
  we call servers_init() anyway).

mysql-test/include/wait_show_condition.inc:
  Print failing statement if timeout
mysql-test/r/myisam-metadata.result:
  Updated DBUG_SYNC
mysql-test/t/myisam-metadata.test:
  Updated DBUG_SYNC.
  Removed wait_show_condtion, as this is not needed when we use DBUG_SYNC
  This should fix timing issues with the test
mysys/thr_mutex.c:
  Added comments
sql/sql_acl.cc:
  atoi -> atoll()  (Safety)
storage/myisam/ha_myisam.cc:
  Send signal before mi_repair_by_sort.

Test case fixes.

Fix problems related to reconnect. When we need to reconnect (ie. explict
stop/start of just the IO thread by user, or automatic reconnect due to
loosing network connection with the master), it is a bit complex to correctly
resume at the right point without causing duplicate or missing events in the
relay log. The previous code had multiple problems in this regard.

With this patch, the problem is solved as follows. The IO thread keeps track
(in memory) of which GTID was last queued to the relay log. If it needs to
reconnect, it resumes at that GTID position. It also counts number of events
received within the last, possibly partial, event group, and skips the same
number of events after a reconnect, so that events already enqueued before the
reconnect are not duplicated.

(There is no need to keep any persistent state; whenever we restart slave
threads after both of them being stopped (such as after server restart), we
erase the relay logs and start over from the last GTID applied by SQL thread.
But while the SQL thread is running, this patch is needed to get correct relay
log).

Test fixes.

sql/sp_head.cc:
  Trigger MYSQL_AUDIT_GENERAL_STATUS event for each statement in stored
  procedures. Not strictly needed for query_response_time plugin, but
  makes it behave more like Percona patch.

There were several cases where the slave GTID position was not loaded
correctly before being used. This caused various failures such as
corrupting the position at slave start and empty values of
@@gtid_slave_pos and @@gtid_current_pos.

Fixed by adding more checks for loaded position, and by always loading
the position at server startup.

Problem : 
libreadline.so was already present on the machine, however the cmake check NEW_READLINE_INTERFACE was unsuccessfull indicating, thus bundled library had to be used instead of  system library.
The problem was that the value for HAVE_HIST_ENTRY cmake variable  was cached with incorrect  value (1 on NetBSD).

The fix is to change HAVE_HIST_ENTRY to 0 with  CACHE FORCE, after switching to bundled readline.

MDEV-4520: Assertion `0' fails in Query_cache::end_of_result on concurrent drop event and event executio

Fix for embedded library, where thd->net.vio is not set which efficently switched off QC in emmbedded server for previous patch.

Fix the error handling when access to the table mysql.gtid_slave_pos
fails for whatever reason. Add some test cases.

MDEV-4485: Master did not allow slave to connect from the very start (empty GTID pos) if GTIDs from other multi_source master was present

The idea in the code was to protect the user that tries to connect a slave
to a master with completely different domains than what was intended. If
none of the domains in the start position are present at all in the master
binlog, we gave an error.

However, this is a stupid idea. Because when a slave connects to a master
to start replication from the very start of binlogs - such as when setting
up new master->slave servers from scratch - there will be just this
situation, the requested slave position is empty for all the domains in the
master's binlog.

So the code that gives this error is wrong, and the solution is simply to
remove it.

remove the workaround from cmake/os/FreeBSD.cmake

When @@GLOBAL.gtid_strict_mode=1, then certain operations result
in error that would otherwise result in out-of-order binlog files
between servers.

GTID sequence numbers are now allocated independently per domain;
this results in less/no holes in GTID sequences, increasing the
likelyhood that diverging binlogs will be caught by the slave when
GTID strict mode is enabled.

The problem was the Gtid_list event which is logged to the binlog in
10.0 and is not understood by the 5.5 server.

This event is supposed to be replaced with a dummy event for 5.5
servers. But the very first event logged in the very first binlog
has an empty list of GTID, which makes the event too short to be
replacable with an empty event.

The fix is to pad the empty Gtid_list event to be big enough to
be replacable by a dummy event.

MDEV-4520: Assertion `0' fails in Query_cache::end_of_result on concurrent drop event and event execution

If there is no net.vio then query cache cant't get data via net_real_write() so it is better just do not try to cache such query.

Change of user interface to be more logical and more in line with expectations
to work similar to old-style replication.

User can now explicitly choose in CHANGE MASTER whether binlog position is
taken into account (master_gtid_pos=current_pos) or not (master_gtid_pos=
slave_pos) when slave connects to master.

@@gtid_pos is replaced by three separate variables @@gtid_slave_pos (can
be set by user, replicated GTIDs only), @@gtid_binlog_pos (read only), and
@@gtid_current_pos (a combination of the two, most recent GTID within each
domain). mysql.rpl_slave_state is renamed to mysql.gtid_slave_pos to match.

This fixes MDEV-4474.

replaced snippets_udf.cc with the latest version (2.0.8 from sphinxsource.com), fixed trivial errors on Windows.
It will be compiled and installed into plugins directory now.

if qc->try_lock() fails, it's not an error

(part 2)

change maria.distinct to use a function that doesn't require ssl-enabled  builds

with query cache, charset ucs2 and collation ucs2_unicode_ci

  @ mysql-test/r/ctype_ucs2_query_cache.result
  @ mysql-test/t/ctype_ucs2_query_cache-master.opt
  @ mysql-test/t/ctype_ucs2_query_cache.test
    Adding tests

  @ sql/sql_cache.cc
    Fixing not to use default_character_set->state_map,
    which can point to a non-ASCII character set (utc2, utf16, utf32)
   and thus have state_map undefined.