Fix a failure in rocksdb_rpl.rpl_rocksdb_2pc_crash_recover test.
Don't do XA with binlog if @@rocksdb_enable_2pc=OFF.

gcc 5.4 and 7.1, Debug and Release builds

remove remnants of 10.0 bugfix, incorrectly merged into 10.2

Using col_names[i] was obviously, wrong, must've been col_names[ifield->col_no].
incorrect column name resulted in innodb having index unique_id2(id1),
while the server thought it's unique_id2(id4).
But col_names[ifield->col_no] is wrong too, because `table` has non-renamed
columns, so the correct column name is always dict_table_get_col_name(table, ifield->col_no)

$WSREP_SST_OPT_CONF already includes --defaults-extra-file= prefix.

allow to build with the default port number 3306.
Now -DMYSQL_TCP_PORT=# sets the default port name and
-DMYSQL_TCP_PORT_DEFAULT=# sets the magic port=0 behavior,
if it's MYSQL_TCP_PORT_DEFAULT=0 it's enabled, otherwise - disabled.

Use mariadb_config, for C/C config variables

MDEV-13918 Race condition between INFORMATION_SCHEMA.INNODB_SYS_TABLESTATS and ALTER/DROP/TRUNCATE TABLE

i_s_sys_tables_fill_table_stats(): Acquire dict_operation_lock
S-latch before acquiring dict_sys->mutex, to prevent the table
from being removed from the data dictionary cache and from
being freed while i_s_dict_fill_sys_tablestats() is accessing
the table handle.

Issue
=====
The original issue was that the size of a fil_per_table tablespace was calculated
incorrectly during truncate in the presence of an fts index. This incorrect calculation
was fixed as part of BUG#25053705 along with a testcase to reproduce the bug. The
assert that was added as part of it to reproduce the bug was wrong and resulted in
this bug.

Fix
===
Although the assert was removed earlier in a seperate commit as it was blocking the
ntest, this patch replaces the other parts of the code that were added to reproduce
the bug and replaces it with code that tries to reproduce the bug in a different way.

The new code basically tries to tweak conditions so as to simulate the random read
where a page that doesn't exist is tried to be read.

RB: 15890
Reviewed-by: Jimmy Yang <Jimmy.Yang@oracle.com>
Reviewed-by: Satya Bodapati <satya.bodapati@oracle.com>

The ownership of the field query->intersection usually transfers
to query->doc_ids. In some error scenario, it could be possible
that fts_query_free() would be invoked with query->intersection!=NULL.
Let us handle that case, instead of intentionally crashing the server.

MySQL 5.7 added code to push down the LIMIT to fulltext search
in InnoDB:

commit 2cd0ebf97e1b265e2282d7ceb5d8dfb663ffc48f
Author: Thirunarayanan Balathandayuthapani <thirunarayanan.balathandayuth@oracle.com>
Date:   Fri May 27 13:49:28 2016 +0530

    Bug #22709692   FTS QUERY EXCEEDS RESULT CACHE LIMIT

The code was disabled when MySQL 5.7.9 was merged to MariaDB 10.2.2.

We shall remove the disabled code and unnecessary variables.

In MariaDB, InnoDB fulltext search does not currently
truncate results based on LIMIT. In MySQL 5.7, it does.

MDEV-14086 Setting innodb_buffer_pool_load_now or innodb_buffer_load_abort will crash if innodb_read_only

When MySQL 5.6.10 introduced innodb_read_only mode, it skipped the
creation of the InnoDB buffer pool dump/restore subsystem in that mode.
Attempts to set the variable innodb_buf_pool_dump_now would have
no effect in innodb_read_only mode, but the corresponding condition
was forgotten in from the other two update functions.

MySQL 5.7.20 would fix the innodb_buffer_pool_load_now,
but not innodb_buffer_pool_load_abort. Let us fix both in MariaDB.

Port the previous patch:
- Implement MariaDB's Group Commit API. This is a first
   attempt which lacks the expected performance.

To newer MariaDB (which includes newer MyRocks)

based on:

commit f7316aa0
Author: Ajo Robert <ajo.robert@oracle.com>
Date:   Thu Aug 24 17:03:21 2017 +0530

    Bug#26361149  MYSQL SERVER CRASHES AT: COL IN(IFNULL(CONST,
                           COL), NAME_CONST('NAME', NULL))

    Backport of Bug#19143243 fix.

    NAME_CONST item can return NULL_ITEM type in case of incorrect arguments.
    NULL_ITEM has special processing in Item_func_in function.
    In Item_func_in::fix_length_and_dec an array of possible comparators is
    created. Since NAME_CONST function has NULL_ITEM type, corresponding
    array element is empty. Then NAME_CONST is wrapped to ITEM_CACHE.
    ITEM_CACHE can not return proper type(NULL_ITEM) in Item_func_in::val_int(),
    so the NULL_ITEM is attempted compared with an empty comparator.
    The fix is to disable the caching of Item_name_const item.

fil_mutex_enter_and_prepare_for_io(): Reacquire fil_system->mutex after
failing to close a file and before retrying.

Partition wasn't setting HA_OPTION_PACK_RECORD on ALTER TABLE
if the row format was PAGE.

(so one bit in the null bitmap was reserved for a deleted bit -
see make_empty_rec - and all actual null bits were one off)

if it's a DROP TABLE, we cannot detect whether a table is
temporary by looking in thd->temporary_tables - because the
table might simply not exist at all.

backport ce6c0e58

MDEV-8960: Can't refer the same column twice in one ALTER TABLE

Problem was that if column was created in alter table when
it was refered again it was not tried to find from list
of current columns.

mysql_prepare_alter_table:
  There is two cases
    (1) If alter table adds a new column and then later alter
        changes the field definition, there was no check from
	list of new columns, instead an incorrect error was given.
    (2) If alter table adds a new column and then later alter
        changes the default, there was no check from list of
	new columns, instead an incorrect error was given.

always search in compile-time specified paths
INSTALL_BINDIR, INSTALL_SBINDIR, INSTALL_MYSQLSHAREDIR. User
can set them to arbitrary values, it's not enough to search only
in their usual values of bin, sbin and libexec, share and share/mysql.

1. detect resolveip location, don' assume it's in $basedir/bin
2. don't guess $scriptdir to (incorrectly) construct the $0 path
3. rename find_in_basedir -> find_in_dirs, don't prepend $basedir
   automatically. This allows to use identical path lists in
   find_in_dirs and in cannot_find_file.
4. move search path lists to CMakeLists.txt to avoid specifying the
   same path list twice (in find_in_dirs and in cannot_find_file).

mostly caused by -Wimplicit-fallthrough

MDEV-14076 InnoDB: Failing assertion when accessing INFORMATION_SCHEMA.INNODB_SYS_TABLESPACES upon upgrade from 10.1.0 to 10.1.20

i_s_dict_fill_sys_tablespaces(): Adjust the tablespace flags if needed.

fts_get_next_doc_id(): Assign the first and subsequent FTS_DOC_ID
in the same way: by post-incrementing the cached value.
If there is a user-specified FTS_DOC_ID, do not touch the internal
sequence.

There are two bugs related to failed ADD INDEX and
the InnoDB table cache eviction.

dict_table_close(): Try dropping failed ADD INDEX when releasing
the last table handle, not when releasing the last-but-one.

dict_table_remove_from_cache_low(): Do not invoke
row_merge_drop_indexes() after freeing all index metadata.
Instead, directly invoke row_merge_drop_indexes_dict() to
remove the metadata from the persistent data dictionary
and to free the index pages.

MDEV-10802 TIMESTAMP NOT NULL field with explicit_defaults_for_timestamp and NO_ZERO_DATE shouldn't throw error

This was a false alarm in a debug check that was introduced in
commit 48192f96 which was a
10.2 code refactoring in preparation for
MDEV-11369 (instant ADD COLUMN) in 10.3.2. The code refactoring
only affected debug builds.

InnoDB B-tree record locks are only supposed to exist on leaf page
records. An assertion failed, because the debug function lock_validate()
was invoking lock_rec_block_validate() on a page for which there were
no locks set in the record lock bitmap. This could happen on a page split.
Especially when the index size grows from a single page to multiple pages,
the root page would transform from a leaf node into an internal node,
and its record lock bitmap would be emptied.

lock_validate(): Skip empty lock bitmaps.