We may get r_index_rows=0. Do not divide by 0 in this case,
as the result is undefined. Produce "r_total_filtered": 100 instead.

Error:Run-Time Check Failure #3 - The variable 'r_filtered' is being used without being initialized. At :0

Add assertions about limitations one has when using Index Condition
Pushdown:
- add handler::assert_icp_limitations()
- call this function from functions that may attempt violations.

Verified that assert_icp_limitations() as well as calls to it are
compiled away in release build.

Support index condition pushdown within partitioned tables.
- ha_partition will pass the pushed index condition into all of the used
  partitions.
  - We require that all of the partitions to handle the pushed index
    condition in the same way.
- When using ICP, one may read rows (e.g. call h->index_read_map(buf, ...)
  only to buf= table->record[0], for two reasons:
  * Pushed index condition's Item_field objects point into record[0]
  * InnoDB requires this: it calls offset() which assumes record[0].
  So, when using ICP, ha_partition will read partition records to
  table->record[0] and then will copy record away if it needs it to be
  elsewhere.

Part#2, variant 2: Make the printed r_ values in JSON output consistent.
After this patch, ANALYZE output has:

- r_index_rows (NEW) - Observed number of rows before ICP or Rowid Filtering
  checks. This is a per-scan average. like r_rows and "rows" are.

- r_rows (AS BEFORE) - Observed number of rows after ICP and Rowid Filtering.

- r_icp_filtered (NEW) - Observed selectivity of ICP condition.

- (AS BEFORE) observed selectivity of Rowid Filter is in
  $.rowid_filter.r_selectivity_pct

- r_total_filtered - Observed combined selectivity: fraction of rows left
  after applying ICP condition, Rowid Filter, and attached_condition.
  This is now comparable with "filtered" and is printed right after it.

- r_filtered (AS BEFORE) - Observed selectivity of "attached_condition".

Tabular ANALYZE output is not changed. Note that JSON's r_filtered and
r_rows have the same meanings as before and have the same meaning as in
tabular output.

(Based on the original patch by Jason Cu)

Part #1:
- Add ha_handler_stats::{icp_attempts,icp_match}, make
  handler_index_cond_check() increment them.
- ANALYZE FORMAT=JSON now prints r_icp_filtered based on these counters.

AIX compilation failed, because glibc's non-standard extension to
`struct tm` were used - additional members tm_gmtoff and tm_zone.

The patch fixes it by adding corresponding compile-time check.

Additionally, for the calculation of GMT offset on AIX, a portable
variant of timegm() was required.Implementation here is inspired by
SergeyD's answer on Stackoverflow :
https://stackoverflow.com/questions/16647819/timegm-cross-platform

make_item_func_call_generic() should take `db_int`, not `db`

btr_pcur_move_to_next_page(): Add code that was wrongly deleted in
the merge commit 8c8bce05

Errors outputted as notes are weird, and when a user
cannot do anything about them, why output them at all.

Point taken, removed these, and left positive message
on initialization (from Marko).

Thanks Elena Stepanova.

mariadb-backup wasn't meant to have memory pressure
sensors so restrict the operation to SRV_OPERATIONAL_NORMAL
mode.

Reviewed by Daniel Black.

trx_purge_truncate_history(): If a fast shutdown has been initiated,
disregard innodb_undo_log_truncate=ON and return.

The previous patch for MDEV-10653 changes the rpl_parallel::workers_idle()
function to use Relay_log_info::last_inuse_relaylog to check for idle
workers. But the code was missing a NULL check. Also, there was one place
during SQL slave thread start which was missing mutex synchronisation when
updating inuse_relaylog.
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>

The error-injection inject_mdev8031 simulates a deadlock kill in a specific
place, by setting killed_for_retry to RETRY_KILL_KILLED directly. If a real
deadlock kill triggers at the same time, it is possible for the thread to
complete its transaction retry and set rgi_slave to NULL before the real
readlock kill can complete in the background. This will cause a segfault
due to null-pointer access.

Fix by changing the error injection to do a real background deadlock kill,
which ensures that the thread will wait for any pending background kills to
complete.
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>

Item::val_str() sets the Item::null_value flag, so call it before checking
the flag, not after.
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>

trx_purge_truncate_history(): Release buf_pool.flush_list_mutex
and 'dummily' acquire and release buf_pool.mutex before starting
a rescan of buf_pool.flush_list, to ensure that
the buf_flush_page_cleaner thread (which may be holding buf_pool.mutex)
will be able to proceed.

This fixes up commit 5dbe7a8c (MDEV-32757).

Tested by: Axel Schwenke (on Ubuntu 18.04 and Ubuntu 20.04)
Reviewed by: Vladislav Lesin

This commit addresses the file leakage problem encountered with the mysql_upgrade --check-if-upgrade-is-needed command.

e.g. it could be

{"errors":["no handler for route \"mariadbtest/data/1\". route entry not found."]}

ASAN uses *a lot* more stack. use not_asan.inc for tests
that recursively put a lot of data on the stack

"InnoDB: The last skipped log record LSN X is not equal to page LSN Y"
is not an actionable message for the user, so it should be a note, not
a warning

to iterate over all status variables one should use
LOCK_all_status_vars not LOCK_status

this fixes sporadic mutex lock inversion in plugins.password_reuse_check:
* acl_cache->lock is taken over complex operations that might increment
  status counters (under LOCK_status).
* acl_cache->lock is needed to get the values of Acl% status variables
  when iterating over status variables

This patch adds PACKAGE support with SQL/PSM dialect for sql_mode=DEFAULT:

- CREATE PACKAGE
- DROP PACKAGE
- CREATE PACKAGE BODY
- DROP PACKAGE BODY
- Package function and procedure invocation from outside of the package:
    -- using two step identifiers
    SELECT pkg.f1();
    CALL pkg.p1()

    -- using three step identifiers
    SELECT db.pkg.f1();
    CALL db.pkg.p1();

This is a non-standard MariaDB extension.

However, later this code can be used to implement
the SQL Standard and DB2 dialects of CREATE MODULE.

variable

Analysis:
Since the item is NULL, it's json value is NULL but we proceed to parse
it anyway.
Fix:
If json value is NULL, return NULL.

buf_read_ahead_linear(): Suppress a warning of comparing potentially
uninitialized FIL_PAGE_PREV and FIL_PAGE_NEXT fields.

This file isn't used by client or server. Its
functionality is purely in the generation of *.sys
files.

As such omit from packaging and save ~1MB.