MDEV-34274: Test rpl.rpl_change_master_demote frequently fails on buildbot with "IO thread should not be running..."

The test rpl.rpl_change_master_demote used a `sleep 1` command
to give time for a START SLAVE UNTIL to start the slave threads
and wait for them to automatically die by UNTIL.  On machines
with heavy load (especially MSAN bb builders), one second was
not enough, and the test would fail due to the IO thread
still being up.

This patch fixes the test by replacing the sleep with specific
conditions to wait for. The test cannot wait for the IO or SQL
threads to start, as it would be possible that they would be
started and stopped by the time the MTR executor would check
the slave status. So instead, we test for proof that they
existed via the Connections status variable being incremented
by at least 2 (Connections just shows the global thread id).
At this point, we still can't use the wait_for_slave_to_stop
helper, as the SQL/IO_Running fields of SHOW SLAVE STATUS
may not be updated yet. So instead, we use
information_schema.processlist, which would show the presence
of the Slave_SQL/IO threads. So to "wait for the slave to stop",
we wait for the Slave_SQL/IO threads to be gone from the
processlist.

Let us relax an assertion that would fail in
./mtr main.1st --mysqld=--innodb-undo-tablespaces=127

This avoids a lot of SETVAL() results when applying a mysqldump with
sequences.

To make this possible, it was also necessary to enhance the mariadb
client with the option --print-query-on-error.
This option can also be very useful when running a batch of queries
through the mariadb client and one wants to find out where things goes
wrong.

TODO: It would be good to enhance mariadb_upgrade to not call the mariadb
client for executing queries but instead do this internally.  This
would have made this patch much easier!

Reviewed by: Sergei Golubchik <serg@mariadb.com>

- During recovery, InnoDB may fail to shrink the undo tablespaces
when there are no pages to recover while applying the redo log.
This issue exists only when innodb_undo_truncate is enabled.
trx_lists_init_at_db_start() could've applied the redo logs
for undo tablespace page0.

This fixes up the merge commit 829cb1a4

On an UBSAN clang-15 build, if running with UBSAN option
halt_on_error=1 (the issue doesn't show up without it),
MTR fails during mysqld --bootstrap with UBSAN error:

call to function io_callback(tpool::aiocb*) through pointer to incorrect function type 'void (*)(void *)'

This patch corrects the parameter type of io_callback
to match its expected type defined by callback_func,
i.e. (void*).

Reviewed By:
============
<TODO>

Problem:
=======
During recovery, InnoDB fails to apply the redo log for
compressed tablespace. The reason is that InnoDB assumes
that pages has been freed while applying the redo log for it.
During multiple scan of redo logs, InnoDB stores the freed
page information when it have sufficient buffer pool pages.
Once it ran out of memory, InnoDB doesn't store freed page
information. But InnoDB assigns the freed page ranges to tablespace
in recv_init_crash_recovery_spaces() even though
InnoDB doesn't have complete freed range information.
While applying the redo log, InnoDB wrongly assumes that page
has been freed and it could lead to corruption of tablespace.
This issue is caused by commit 941af1fa (MDEV-31803)
and commit 2f9e2647 (MDEV-29911).

Solution:
========
During recovery, set recovery size and freed page information
for all tablespace irrespective of memory.

The bug can happens on macOS, if server closes the socket without sending
error packet to client. Closing the socket on server side is legitimate,
and happen e.g when write timeout occurs, perhaps also other situations.

However mysqltest is not prepared to handle mysql_errno 0, and erroneously
thinks connection was successfully established.

The fix/workaround in mysqltest is to treat client failure with
mysql_errno 0 the same as CR_SERVER_LOST (generic client-side
communication error)

The real fix in client library would ensure that mysql_errno is set
on errors.

Otherwise it may result in nonsensical values like 190 for a boolean.

Immediately close down the signal handler loop when we decide to
break connections as it's the start of process termination
anyway, and there's no need to wait once we've invoked break_connections.

The problem is that the test could query the status variable
Rpl_semi_sync_slave_send_ack before the slave actually updated it.
This would result in an immediate --die assertion killing the rest
of the test. The bottom of this commit message has a small patch
that can be applied to reproduce the test failure.

This patch fixes the test failure by waiting for the variable to be
updated before querying its value.

diff --git a/sql/semisync_slave.cc b/sql/semisync_slave.cc
index 9ddd4c5c8d7..60538079fce 100644
--- a/sql/semisync_slave.cc
+++ b/sql/semisync_slave.cc
@@ -303,7 +303,10 @@ int Repl_semi_sync_slave::slave_reply(Master_info *mi)
     reply_res= DBUG_EVALUATE_IF("semislave_failed_net_flush", 1,
                                 net_flush(net));
     if (!reply_res)
+    {
+      sleep(1);
       rpl_semi_sync_slave_send_ack++;
+    }
   }
   DBUG_RETURN(reply_res);
 }

--skip-not-found switch tells mtr to skip not found tests instead of aborting.
But it failed to skip the test if the suite name was not found.

This problem also made the *last-N-failed builbot builders fail
to run `mtr --skip-not-found` if the last commit removed a file in
the mysql-test/include/ directory.

This commit fixes it, now the not found test is properly skipped,
no matter what component of the test name was not found:

$ ./mtr main.foo --skip-not-found foo.main
...
==============================================================================
TEST                                  WORKER RESULT   TIME (ms) or COMMENT
--------------------------------------------------------------------------
foo.main                                 [ skipped ]  not found
main.foo                                 [ skipped ]  not found
--------------------------------------------------------------------------

In cmake -DWITH_UBSAN=ON builds with clang but not with GCC,
-fsanitize=undefined will flag several runtime errors on
function pointer mismatch related to the lock-free hash table LF_HASH.

Let us use matching function signatures and remove function pointer
casts in order to avoid potential bugs due to undefined behaviour.

These errors could be caught at compilation time by
-Wcast-function-type-strict, which is available starting with clang-16,
but not available in any version of GCC as of now. The old GCC flag
-Wcast-function-type is enabled as part of -Wextra, but it specifically
does not catch these errors.

Reviewed by: Vladislav Vaintroub

MDEV-34227 On startup: UBSAN: runtime error: applying non-zero offset in JOIN::make_aggr_tables_info in sql/sql_select.cc

Avoid undefined behaviour (applying offset to nullptr).
The reported scenario is covered in mysql-test/connect-no-db.test
No new tests needed.

MDEV-32376 SHOW CREATE DATABASE statement crashes the server when db name contains some unicode characters, ASAN stack-buffer-overflow

Adding the test for the length of lex->name into show_create_db().

Without this test writes beyond the end of db_name_buff were possible
upon a too long database name.

MDEV-34237: On Startup: UBSAN: runtime error: call to function MDL_lock::lf_hash_initializer lf_hash_insert through pointer to incorrect function type 'void (*)(st_lf_hash *, void *, const void *)'

A few different incorrect function type UBSAN issues have been
grouped into this patch.

The only real potentially undefined behavior is an error about
show_func_mutex_instances_lost, which when invoked in
sql_show.cc::show_status_array(), puts 5 arguments onto the stack;
however, the implementing function only actually has 3 parameters (so
only 3 would be popped). This was fixed by adding in the remaining
parameters to satisfy the type mysql_show_var_func.

The rest of the findings are pointer type mismatches that wouldn't
lead to actual undefined behavior. The lf_hash_initializer function
type definition is

typedef void (*lf_hash_initializer)(LF_HASH *hash, void *dst, const void *src);

but the MDL_lock and table cache's implementations of this function
do not have that signature. The MDL_lock has specific MDL object
parameters:

static void lf_hash_initializer(LF_HASH *hash __attribute__((unused)),
                                MDL_lock *lock, MDL_key *key_arg)

and the table cache has specific TDC parameters:

static void tdc_hash_initializer(LF_HASH *,
                                 TDC_element *element, LEX_STRING *key)

leading to UBSAN runtime errors when invoking these functions.

This patch fixes these type mis-matches by changing the
implementing functions to use void * and const void * for their
respective parameters, and later casting them to their expected
type in the function body.

Note too the functions tdc_hash_key and tc_purge_callback had
a similar problem to tdc_hash_initializer and was fixed
similarly.

Reviewed By:
============
Sergei Golubchik <serg@mariadb.com>

The code is slightly simplified taking into account
the fact that partition_ht() always returns a normal
hton when there is no partitioning.

This is regression from commit 3228c08f. Problem is that
when table storage engine is determined there should be
check is table partitioned and if it is then determine
partition implementing storage engine.

Reported bug is reproducible only with --log-bin so make
sure tests changed by 3228c08f and new test are run
with --log-bin and binlog disabled.
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>

The strncpy() wrapper that was introduced in
commit 567b6812
is checking whether the output was truncated even in cases
where the caller does not care about it.

Let us introduce a separate function safe_strcpy_truncated() that
indidates whether the output was truncated.

              number of non-user tablespace.

fil_space_t::try_to_close(): Don't try to close
the tablespace which is acquired by the caller of
the function

Added the suppression message in open_files_limit test case

"Process" sandbox short command put by masqldump to avoid an error.

In commit 9ec7819c the CRC-32 function
signatures had been unified somewhat, but not enough.

clang -fsanitize=undefined would flag a function pointer signature
mismatch between const char* and const void*, but not between
uint32_t and unsigned. We try to fix both inconsistencies anyway.

Reviewed by: Vladislav Vaintroub

		number of non-user tablespace.

- InnoDB only closes the user tablespace when the number of open
files exceeds innodb_open_files limit. In that case, InnoDB should
make sure that innodb_open_files value should be greater
than number of undo tablespace, system and temporary tablespace files.

wsrep_sst_mariabackup should use the tmpdir defined by
the user under the '[mysqld]' section of the configuration
file rather than the default '/tmp' directory.

Some galera tests starts 6 galera nodes. Each galera node requires
three ports: 6*3 = 18. Plus 6 ports are needed for 6 mariadbd servers.
Since the number of ports is rounded up to 10 everywhere in mtr, we
will take 30 as the default value for the port group size parameter.

Avoid starting transactions in wsrep-lib side when wsrep is
disabled. It is unnecessary, and causes spurious deadlock errors on
transaction clean up.
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>