Item_func_json_merge fixed.

        'JSON' made possible identifier.

        Now return the argument's value when error.

Merge pull request #268 from grooverdan/10.2-MDEV-10651-enable-test-sys_vars.innodb_buffer_pool_dump_pct_basic

MDEV-10651: enable test sys_vars.innodb_buffer_pool_dump_pct_basic

MDEV-11451: isinf || isnan -> !isfinite

crashes server

This bug is the result of merging the Oracle MySQL follow-up fix
BUG#22963169 MYSQL CRASHES ON CREATE FULLTEXT INDEX
without merging the base bug fix:
Bug#79475 Insert a token of 84 4-bytes chars into fts index causes
server crash.

Unlike the above mentioned fixes in MySQL, our fix will not change
the storage format of fulltext indexes in InnoDB or XtraDB
when a character encoding with mbmaxlen=2 or mbmaxlen=3
and the length of a word is between 128 and 84*mbmaxlen bytes.
The Oracle fix would allocate 2 length bytes for these cases.

Compatibility with other MySQL and MariaDB releases is ensured by
persisting the used maximum length in the SYS_COLUMNS table in the
InnoDB data dictionary.

This fix also removes some unnecessary strcmp() calls when checking
for the legacy default collation my_charset_latin1
(my_charset_latin1.name=="latin1_swedish_ci").

fts_create_one_index_table(): Store the actual length in bytes.
This metadata will be written to the SYS_COLUMNS table.

fts_zip_initialize(): Initialize only the first byte of the buffer.
Actually the code should not even care about this first byte, because
the length is set as 0.

FTX_MAX_WORD_LEN: Define as HA_FT_MAXCHARLEN * 4 aka 336 bytes,
not as 254 bytes.

row_merge_create_fts_sort_index(): Set the actual maximum length of the
column in bytes, similar to fts_create_one_index_table().

row_merge_fts_doc_tokenize(): Remove the redundant parameter word_dtype.
Use the actual maximum length of the column. Calculate the extra_size
in the same way as row_merge_buf_encode() does.

        Item_func_json_extract::val_str fixed.

        Item_func_json_length::val_int fixed.

        Test case added.

        Item_func_json_array_append::val_str fixed.

        Item_func_json_array_insert::val_str fixed.

        Item_func_json_remove::val_str fixed.

        Item_func_json_depth::val_int fixed.

Since 10.2 (2e814d47) this test
changed and the race condition of MDEV-10651 no longer forms part
of this test.

As such re-enable this test.

Also include save/restore of the default values of this variable.
Signed-off-by: Daniel Black <daniel.black@au.ibm.com>

There are only 3 logical states for a number. The isfinite is a
single function call rather than multiple leaving scope for compiler
/architecture optimization.

Changed the logic as follows in a few files.

my_isinf(square) || my_isnan(square) -> !isfinite(square)
Signed-off-by: Daniel Black <daniel.black@au.ibm.com>

        Integer/Double recognition added.

        Create_func_json_contains::create_native fixed.

        Create_func_json_merge::create_native fixed.

        json_quote fixed.

        fix_length_and_dec() didn't calculate the length of the result
        properly.

MDEV-11438 Assertion `null_value' failed in Item::send(Protocol*, String*) upon casting NULL as JSON.

        test added.

        Depth of nested objects should be controlled.

        The depth of nested arrays should be controlled, as it's limited.

        Item_func_json_search::val_str didn't set the null_value
        properly. So that affected the next record in the resultset.

        JSON_ARRAY didn't expect 0 arguments.

        CAST AS JSON didn't set the null_value mark properly.

        Some JSON functions didn't expect NULL as a path.

MDEV-11442 Server crashes in String::length / parse_one_or_all /Item_func_json_contains_path::val_int

        Didn't expect 'one_or_all' parameter to be NULL.

        Wrong 'value_lengh' taken

MDEV-11168: InnoDB: Failing assertion: !other_lock || wsrep_thd_is_BF(lock->trx->mysql_thd, FALSE) || wsrep_thd_is_BF(other_lock->trx->mysql_thd, FALSE)

Merge fix from 10.1.

trx_state_eq(): Add the parameter bool relaxed=false, to
allow trx->state==TRX_STATE_NOT_STARTED where a different
state is expected, if an error has been reported.

trx_release_savepoint_for_mysql(): Pass relaxed=true to
trx_state_eq(). That is, allow the transaction to be idle
when ROLLBACK TO SAVEPOINT is attempted after an error
has been reported to the client.

MDEV-9451: Remove innodb_buffer_pool_populate from xtradb (10.2)

MySQL 5.7 introduced WL#7943: InnoDB: Implement Information_Schema.Files
to provide a long-term alternative for accessing tablespace metadata.
The INFORMATION_SCHEMA.INNODB_* views are considered internal interfaces
that are subject to change or removal between releases. So, users should
refer to I_S.FILES instead of I_S.INNODB_SYS_TABLESPACES to fetch metadata
about CREATE TABLESPACE.

Because MariaDB 10.2 does not support CREATE TABLESPACE or
CREATE TABLE…TABLESPACE for InnoDB, it does not make sense to support
I_S.FILES either. So, let MariaDB 10.2 omit the code that was added in
MySQL 5.7. After this change, I_S.FILES will report the empty result,
unless some other storage engine in MariaDB 10.2 implements the interface.
(The I_S.FILES interface was originally created for the NDB Cluster.)

MDEV-11168: InnoDB: Failing assertion: !other_lock || wsrep_thd_is_BF(lock->trx->mysql_thd, FALSE) || wsrep_thd_is_BF(other_lock->trx->mysql_thd, FALSE)

    Problem was that we moved lock request to head of lock queue
    even when lock request has to wait.

MariaDB 10.2 incorporates MySQL 5.7. MySQL 5.7.9 (the first GA release
of the series) introduced an informational field to the InnoDB redo log
header, which identifies the server version where the redo log files
were created (initialized, resized or updated), in
WL#8845: InnoDB: Redo log format version identifier.

The informational message would be displayed to the user, for example
if someone tries to start up MySQL 8.0 after killing a MariaDB 10.2 server.
In the current MariaDB 10.2 source code, the identifier string would
misleadingly say "MySQL 5.7.14" (using the hard-coded version number in
univ.i) instead of "MariaDB 10.2.3" (using the contents of the VERSION
file, the build system copies to config.h and my_config.h).

This is only a cosmetic change. The compatibility check is based on a
numeric identifier.

We should probably also change the numeric identifier and some logic
around it. MariaDB 10.2 should refuse to recover from a crashed MySQL 5.7
instance, because the redo log might contain references to shared tablespaces,
which are not supported by MariaDB 10.2. Also, when MariaDB 10.2 creates
an encrypted redo log, there should be a redo log format version tag that
will prevent MySQL 5.7 or 8.0 from starting up.

Corrected error message when ONLINE alter table with GIS indexes is
used on InnoDB.

innodb_buffer_pool_populate has not had an effect since 10.0.23
in commit 1e270d50 when its
functionality was removed.

As we've only just enabled LIBNUMA in MDEV-10829 it isn't logical
to have innodb_buffer_pool_populate aliasing for innodb_numa_interleave
this late in the game.

So the simpliest way is just to remove innodb_buffer_pool_populate.
Signed-off-by: Daniel Black <daniel.black@au.ibm.com>

The bug was fixed by the patch for mdev-10882.