don't tell users to set the root password if they're using unix_socket

there's an assert that catches it

Don't let SET PASSWORD to set the password, if auth_string is set.

Now SET PASSWORD always sets the plugin/auth_string fields and clears
the password field (on pre-plugin mysql.user table it works as before).

MDEV-14578: mysql_install_db install unix_socket plugin when --auth-root-authentication-method=socket

post-merge fixes

MDEV-14578: mysql_install_db install unix_socket plugin when --auth-root-authentication-method=socket

$ cmake -DPLUGIN_AUTH_SOCKET=STATIC ../mariadb-server-10.2/

$ scripts/mysql_install_db --datadir=/tmp/mysqldatadir-auth-static --auth-root-socket-user=dan --auth-root-authentication-method=socket --builddir=.  --srcdir=../mariadb-server-10.2
Installing MariaDB/MySQL system tables in '/tmp/mysqldatadir-auth-static' ...
OK

$ client/mysql -S /tmp/mysql.sock -e 'show create user dan@localhost'
+----------------------------------------------------------+
| CREATE USER for dan@localhost                            |
+----------------------------------------------------------+
| CREATE USER 'dan'@'localhost' IDENTIFIED VIA unix_socket |
+----------------------------------------------------------+

$ cmake -DPLUGIN_AUTH_SOCKET=NO ../mariadb-server-10.2/
$ scripts/mysql_install_db --datadir=/tmp/mysqldatadir-auth-none --auth-root-socket-user=dan --auth-root-authentication-method=socket --builddir=.  --srcdir=../mariadb-server-10.2
Installing MariaDB/MySQL system tables in '/tmp/mysqldatadir-auth-none' ...
ERROR: 1126  Can't open shared library '.../plugin/auth_socket/auth_socket.so' (errno: 2, cannot open shared object file: No such file or directory)
2018-05-01 11:38:56 0 [ERROR] Aborting

$ cmake -DPLUGIN_AUTH_SOCKET=DYNAMIC ../mariadb-server-10.2/
$ scripts/mysql_install_db --datadir=/tmp/mysqldatadir-auth-dyn --auth-root-socket-user=dan --auth-root-authentication-method=socket --builddir=.  --srcdir=../mariadb-server-10.2
Installing MariaDB/MySQL system tables in '/tmp/mysqldatadir-auth-dyn' ...
OK
$ ./sql/mysqld  --datadir=/tmp/mysqldatadir-auth-dyn  --lc-messages-dir=${PWD}/sql/share --plugin-dir=./plugin/auth_socket/
$ client/mysql -S /tmp/mysql.sock -e 'show create user dan@localhost'
+----------------------------------------------------------+
| CREATE USER for dan@localhost                            |
+----------------------------------------------------------+
| CREATE USER 'dan'@'localhost' IDENTIFIED VIA unix_socket |
+----------------------------------------------------------+

$ sudo make install
$ sudo chmod a+rwx /usr/local/mysql/data
$ cd /usr/local/mysql/
$ scripts/mysql_install_db  --auth-root-socket-user=dan --auth-root-authentication-method=socket
Installing MariaDB/MySQL system tables in './data' ...
OK
..
$ bin/mysqld_safe
$ client/mysql -S /tmp/mysql.sock -e 'show create user dan@localhost'
+----------------------------------------------------------+
| CREATE USER for dan@localhost                            |
+----------------------------------------------------------+
| CREATE USER 'dan'@'localhost' IDENTIFIED VIA unix_socket |
+----------------------------------------------------------+

Merges #767

In RPM/DEB packages - always ld-preload jemalloc, instead
of linking ha_tokudb.so with it.

Keep linking in bintars, because they don't install cnf files
in the correct locations.

This reverts commit d39629f0.

Because running mtr for many hours with no output whatsoever
is not really what we should do.

And in 5.5 `make test` just works anyway, nothing to fix here.

my_option strucures for command-line variables should be set properly.

settings.

MDEV-16534 PPC64: Unexpected error with a negative value into auto-increment columns in HEAP, MyISAM, ARIA

Revert 7bbe324f
Fix the bug differently (in log_event.cc)
Fix the test case to actually fail without the bug fix

RocksDB will only build with libzstd support if libzstd version is
>=1.1.13. Unfortunately CMake's FindPackage claims it found version
1.1.13 when we have 1.1.12-1 installed, so a workaround with
CheckFunctionExists is used to properly check for correct libzstd
support.

In this case we are accessing incorrect memory when we have mergeable semi-joins.
In the case when we have mergeable semi joins parent select will have a table count
of all the tables in that select plus all the tables involved in the IN-subquery.
But this table count does not include the "sjm table" (only includes the inner and outer tables)
denotes as <subquery#> in explain.

            IN predicate defined with non-constant values is pushed down

The problem appears because of wrong changes made in MDEV-16090 in the
Item_func_in::build_clone() method.
For the clone of the IN predicate it copied 'cmp_fields' array values
that become dirty after Item::cleanup_excluding_const_fields_processor
has worked in pushdown. That causes crash.
There is no need to copy 'cmp_fields' field, the array values should be
NULLs in order to fix_fields() for the cloned IN predicate can set them
correctly. fix_fields() computes values for 'cmp_fields' array only
if they were not set earlier.

Added flush tables to ensure that MyISAM tables are
properly flushed before reboot

The bug was that innobase_get_computed_value() trashed record[0] and data
in Field_blob::value

Fixed by using a record on the heap for innobase_get_computed_value()

Reviewer: Marko Mäkelä

This is to mark that a field is indirectly part of a key, which simplifes
checking if we need to have this field up to date to evaluate a key.

For example:
CREATE TABLE t1 (a int, b int as (a) virtual,
                 c int as (b) virtual, index(c))
would mark a and b with PART_INDIRECT_KEY_FLAG.
c is marked with PART_KEY_FLAG as before.

The optimizer can create various item's over the original one,
    so we can't count on the exact item's type inside the comparison.

The following conditions will decide the query cache retrieval or
storing inside innodb:

    (1) There should not be any locks on the table.
    (2) Some other trx shouldn't invalidated the cache before the
    transaction started.
    (3) Read view shouldn't exist. If exists then the view
    low_limit_id should be greater than or equal to the transaction that
    invalidates the cache for the particular table.

 For read-only transaction: should satisfy  the above (1) and (3)
 For read-write transaction: should satisfy the above (1), (2), (3).

 - Changed the variable from query_cache_inv_id to query_cache_inv_trx_id.

 - Moved the function row_search_check_if_query_cache_permitted from
    row0sel.h and made it as static function in ha_innodb.cc

"Truncated incorrect DOUBLE value: 'true'".

JSON_VALUE_TRUE and JSON_VALUE_FALSE should be handled specifically
in Item_json_value.

* xtrabackup no longer support --compact
* wsrep_sst_mysqldump wasn't always using --default-file
* wsrep_sst.cc overquoted --default-file for wsrep_sst_mysqldump

also remove redundant lines config and test lines, compiler warnings,
and mark big tests as big.

srv_print_verbose_log: Introduce the value 2 to refer to
mariabackup --verbose.

recv_recover_page(), recv_parse_log_recs(): Add output for
mariabackup --verbose.

Commit dc9c5554 moved the final phase of
the redo log copying to the background thread. This would sometimes cause
too little redo log to be copied at the end of the backup. We would only
guarantee copying up to the latest redo log checkpoint. This would produce
a consistent backup, but it could refer to a too old point of time.

xtrabackup_copy_log(), xtrabackup_copy_logfile(): Add the parameter 'last'.

xtrabackup_backup_low(): Copy any remaining part of the log after the
backup threads have terminated.

MDEV-11071: Assertion `thd->transaction.stmt.is_empty()' failed in Locked_tables_list::unlock_locked_table

fix_length_and_dec now return result (error/OK)