it's a pointer into the net buffer, so it might be overwritten by the
next read or write. And the next plugin switch (in multi-auth) will
try to compare it (in send_plugin_request_packet) which is normally
harmless but fails the assert with Lex_ident::is_valid_ident()

This patch also fixes:
  MDEV-33050 Build-in schemas like oracle_schema are accent insensitive
  MDEV-33084 LASTVAL(t1) and LASTVAL(T1) do not work well with lower-case-table-names=0
  MDEV-33085 Tables T1 and t1 do not work well with ENGINE=CSV and lower-case-table-names=0
  MDEV-33086 SHOW OPEN TABLES IN DB1 -- is case insensitive with lower-case-table-names=0
  MDEV-33088 Cannot create triggers in the database `MYSQL`
  MDEV-33103 LOCK TABLE t1 AS t2 -- alias is not case sensitive with lower-case-table-names=0
  MDEV-33109 DROP DATABASE MYSQL -- does not drop SP with lower-case-table-names=0
  MDEV-33110 HANDLER commands are case insensitive with lower-case-table-names=0
  MDEV-33119 User is case insensitive in INFORMATION_SCHEMA.VIEWS
  MDEV-33120 System log table names are case insensitive with lower-cast-table-names=0

- Removing the virtual function strnncoll() from MY_COLLATION_HANDLER

- Adding a wrapper function CHARSET_INFO::streq(), to compare
  two strings for equality. For now it calls strnncoll() internally.
  In the future it will turn into a virtual function.

- Adding new accent sensitive case insensitive collations:
    - utf8mb4_general1400_as_ci
    - utf8mb3_general1400_as_ci
  They implement accent sensitive case insensitive comparison.
  The weight of a character is equal to the code point of its
  upper case variant. These collations use Unicode-14.0.0 casefolding data.

  The result of
     my_charset_utf8mb3_general1400_as_ci.strcoll()
  is very close to the former
     my_charset_utf8mb3_general_ci.strcasecmp()

  There is only a difference in a couple dozen rare characters, because:
    - the switch from "tolower" to "toupper" comparison, to make
      utf8mb3_general1400_as_ci closer to utf8mb3_general_ci
    - the switch from Unicode-3.0.0 to Unicode-14.0.0
  This difference should be tolarable. See the list of affected
  characters in the MDEV description.

  Note, utf8mb4_general1400_as_ci correctly handles non-BMP characters!
  Unlike utf8mb4_general_ci, it does not treat all BMP characters
  as equal.

- Adding classes representing names of the file based database objects:

    Lex_ident_db
    Lex_ident_table
    Lex_ident_trigger

  Their comparison collation depends on the underlying
  file system case sensitivity and on --lower-case-table-names
  and can be either my_charset_bin or my_charset_utf8mb3_general1400_as_ci.

- Adding classes representing names of other database objects,
  whose names have case insensitive comparison style,
  using my_charset_utf8mb3_general1400_as_ci:

  Lex_ident_column
  Lex_ident_sys_var
  Lex_ident_user_var
  Lex_ident_sp_var
  Lex_ident_ps
  Lex_ident_i_s_table
  Lex_ident_window
  Lex_ident_func
  Lex_ident_partition
  Lex_ident_with_element
  Lex_ident_rpl_filter
  Lex_ident_master_info
  Lex_ident_host
  Lex_ident_locale
  Lex_ident_plugin
  Lex_ident_engine
  Lex_ident_server
  Lex_ident_savepoint
  Lex_ident_charset
  engine_option_value::Name

- All the mentioned Lex_ident_xxx classes implement a method streq():

  if (ident1.streq(ident2))
     do_equal();

  This method works as a wrapper for CHARSET_INFO::streq().

- Changing a lot of "LEX_CSTRING name" to "Lex_ident_xxx name"
  in class members and in function/method parameters.

- Replacing all calls like
    system_charset_info->coll->strcasecmp(ident1, ident2)
  to
    ident1.streq(ident2)

- Taking advantage of the c++11 user defined literal operator
  for LEX_CSTRING (see m_strings.h) and Lex_ident_xxx (see lex_ident.h)
  data types. Use example:

  const Lex_ident_column primary_key_name= "PRIMARY"_Lex_ident_column;

  is now a shorter version of:

  const Lex_ident_column primary_key_name=
    Lex_ident_column({STRING_WITH_LEN("PRIMARY")});

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.

Values of all session tracking system variables will be sent in the
first ok packet upon connection after successful authentication.

Also updated mtr to print session track info on connection (h/t Sergei
Golubchik) so that we can write mtr tests for this change.

We do this by checking server status. By doing this we avoid printing
session tracking info from previous (but not the last) statement.

The change is from Sergei Golubchik

We add an extra condition that makes the inequality testing in
SEQUENCE::increment_value() mathematically watertight, and we cast to
and from unsigned in potential underflow and overflow addition and
subtractions to avoid undefined behaviour.

Let's start by distinguishing between c++ expressions and mathematical
expressions. by c++ expression I mean an expression with the outcome
determined by the compiler/runtime. by mathematical expression I mean
an expression whose value is mathematically determined. So a c++
expression -9223372036854775806 - 1000 at worst can evaluate to any
value due to underflow. A mathematical expression -9223372036854775806
- 1000 evaluates to -9223372036854776806.

The problem boils down to how to write a c++ expression equivalent to
an mathematical expression x + y < z where x and z can take any values
of long long int, and y < 0 is also a long long int. Ideally we want
to avoid underflow, but I'm not sure how this can be done.

The correct c++ form should be (x + y < z || x < z - y || x < z).
Let M=9223372036854775808 i.e. LONGLONG_MAX + 1. We have

-M < x < M - 1
-M < y < 0
-M < z < M - 1

Let's consider the case where x + y < z is true as a mathematical
expression.

If the first disjunct underflows, i.e. the mathematical expression x
+ y < -M. If the arbitrary value resulting from the underflow causes
the c++ expression to hold too, then we are done. Otherwise we move
onto the next expression x < z - y. If there's no overflow in z
- y then we are done. If there's overflow i.e. z - y > M - 1,
and the c++ expression evals to false, then we are onto x < z.
There's no over or underflow here, and it will eval to true. To see
this, note that

x + y < -M means x < -M - y < -M - (-M) = 0
z - y > M - 1 means z > y + M - 1 > - M + M - 1 = -1
so x < z.

Now let's consider the case where x + y < z is false as a mathematical
expression.

The first disjunct will not underflow in this case, so we move to (x <
z - y). This will not overflow. To see this, note that

x + y >= z means z - y <= x < M - 1

So it evals to false too. And the third disjunct x < z also evals to
false because x >= z - y > z.

I suspect that in either case the expression x < z does not determine
the final value of the disjunction in the vast majority cases, which
is why we leave it as the final one in case of the rare cases of both
an underflow and an overflow happening.

Here's an example of both underflow and overflow happening and the
added inequality x < z saves the day:

x = - M / 2
y = - M / 2 - 1
z = M / 2

x + y evals to M - 1 which is > z
z - y evals to - M + 1 which is < x

We can do the same to test x + y > z where the increment y is positive:

(x > z - y || x + y > z || x > z)

And the same analysis applies to unsigned cases.

It was wrong to derive Item_func_uuid from Item_func_sys_guid,
because the former is a function returning the UUID data type,
while the latter is a string function returning VARCHAR.

As a result of the wrong hierarchy, Item_func_uuid erroneously derived
Item_str_func::fix_fields(), which contains this code:

  /*
    In Item_str_func::check_well_formed_result() we may set null_value
    flag on the same condition as in test() below.
  */
  if (thd->is_strict_mode())
    set_maybe_null();

This code is not relevant to UUID() at all.
A simple fix would be to set_maybe_null(false) in
Item_func_uuid::fix_length_and_dec(). However,
it'd fix only exactly this single consequence of the wrong
class hierarchy, and similar bugs could appear again in
the future. Moreover, we're going to add functions UUIDv4()
and UUIDv7() soon (in 11.6). So it's better to fix the class hierarchy
in the right way before adding these new functions.

Fix:

- Adding a new abstract class Item_fbt_func in the template
  in sql_type_fixedbin.h
- Deriving Item_typecast_fbt from Item_fbt_func
- Deriving Item_func_uuid from Item_fbt_func
- Adding a new helper class UUIDv1. It derives from UUID, and additionally
  initializes the value to "UUID version 1" right in the constructor.
  Note, the new coming soon SQL functions UUIDv4() and UUIDv7()
  will also have corresponding classes UUIDv4 and UUIDv7.

So now UUID() is a pure "returning UUID" function,
like CAST(expr AS UUID) used to be, without any unintentional
artifacts of functions returning VARCHAR/TEXT.

Cleanup:
- Removing the member Item_func_sys_guid::with_dashes,
  as it's not needed any more:
  * Item_func_sys_guid now does not have any descendants any more
  * Item_func_sys_guid::val_str() itself always displays without dashes

Add doxygen markup so comments get picked up. Also fix minor typos and
expand documentation where relevant.
Signed-off-by: Trevor Gross <tmgross@umich.edu>

This avoids non-integral types breaking the call of
sequence_structure().

The corresponding table param was deprecated as part of MDEV-28861

also, don't require -DWITH_SSL=system if OPENSSL_ROOT_DIR is specified

temporarily disable view protocol

sql_sequence.h:233:19: runtime error: signed integer overflow: -9223372036854775808 + -1 cannot be represented in type 'long long int'

followup for 374783c3

This commit removes the WITH_SSL=<custom_location_of_openssl> option,
leaving only -DWITH_SSL=bundled/system.

The rationale behind this removal is as follows:

1. The WITH_SSL=<custom_location_of_openssl> option is obscure
and not widely used.

2. There is no added value in this option compared to using
OPENSSL_ROOT_DIR. In fact, the availability of "helpful" MySQL options
might discourage users from exploring proper CMake options independently.

3. Users may incorrectly assume full MySQL compatibility even with this
option, including undocumented behaviors such as MySQL's preference for static libraries
with WITH_SSL=<custom_location_of_openssl>.

This change simplifies the configuration options and encourages users to
adopt more standardized and documented practices.

This is a refactoring patch, it does not change the behaviour.
The MTR tests are being added only to cover the LIKE predicate better.
(these tests should have been added earlier under terms of MDEV 9711).
This patch does not need its own specific MTR tests.

Moving the duplicate code into a new shared file ctype-wildcmp.inl
and including it from multiple places, to define the following functions:

- my_wildcmp_uca_impl(), in ctype-uca.c

  For utf8mb3, utf8mb4, ucs2, utf16, utf32, using cs->cset->mb_wc().
  For UCA based collations.

- my_wildcmp_mb2_or_mb4_general_ci_impl(), in ctype-ucs2.c:

  For ucs2, utf16, utf32, using cs->cset->mb_wc().
  For general_ci-style collations:
      - xxx_general_ci
      - xxx_general_mysql500_ci
      - xxx_general_nopad_ci

- my_wildcmp_mb2_or_mb4_bin_impl(), in ctype-ucs2.c:

  For ucs2, utf16, utf32, using cs->cset->mb_wc().
  For _bin collations:
      - xxx_bin
      - xxx_nopad_bin

- my_wildcmp_utf8mb3_general_ci_impl(), in ctype-utf8.c

  Optimized for utf8mb3, using my_mb_wc_utf8mb3_quick().

  For general_ci-style collations:
      - utf8mb3_general_ci
      - utf8mb3_general_mysql500_ci
      - utf8mb3_general_nopad_ci

- my_wildcmp_utf8mb4_general_ci_impl(), in ctype-utf8.c

  Optimized for utf8mb4, using my_mb_wc_utf8mb4_quick().

  For general_ci-style collations:
      - utf8mb4_general_ci
      - utf8mb4_general_nopad_ci

New tests display additional information about characters from the BMP range:

- A summary with a COUNT(*) for all distinct combinations of properties
  telling how the "=" and the "LIKE" predicates compare characters to their
  LOWER() and UPPER() variants.

- A detailed list of trciky characters
  for which the "=" and the "LIKE" predicates compare
  LOWER(c)/UPPER(c) variants as not equal to just "c".

Tricky characters include:
 - Turkish letters: ı - small dotless letter i
 - Croatian letters: precombined contractions for Dž, Dz, Lj, Nj
 - Units of measurement: Ω,K,Å (Ohm, Kelvin, Angstrom)
   These ones look very similar to Greek letter Omega,
   Latin letter Kra, Swedish/Finnish letter A with a ring above.

Under terms of MDEV 27490 we'll add support for non-BMP identifiers
and upgrade casefolding information to Unicode version 14.0.0.
In Unicode-14.0.0 conversion to lower and upper cases can increase octet length
of the string, so conversion won't be possible in-place any more.

This patch removes virtual functions performing in-place casefolding:
  - my_charset_handler_st::casedn_str()
  - my_charset_handler_st::caseup_str()
and fixes the code to use the non-inplace functions instead:
  - my_charset_handler_st::casedn()
  - my_charset_handler_st::caseup()

Only add innodb_async_reads/writes_total_count here.
For all other counters, writing reproducible tests is rather tricky.

Requested by Marko during review

Provide some statistics about asynchronous IO reads and writes:
 - number of pending operations
 - number of completion callbacks that are currently being executed
 - number of completion callbacks that are currently queued
   (due to restriction on number of IO threads)
 - total number of IOs finished
 - total time to wait for free IO slot
 - total number of completions that were queued.

Also revert tpool InnoDB perfschema instrumentation (MDEV-31048)
That instrumentation of cache mutex did not bring any revelation (
the mutex is taken for a couple of instructions), and made it impossible
to use tpool outside of the server (e.g in mariadbimport/dump)

- Add `as <int_type>` to sequence creation options
  - int_type can be signed or unsigned integer types, including
    tinyint, smallint, mediumint, int and bigint
  - Limitation: when alter sequence as <new_int_type>, cannot have any
    other alter options in the same statement
  - Limitation: increment remains signed longlong, and the hidden
    constraint (cache_size x abs(increment) < longlong_max) stays for
    unsigned types. This means for bigint unsigned, neither
    abs(increment) nor (cache_size x abs(increment)) can be between
    longlong_max and ulonglong_max
- Truncating maxvalue and minvalue from user input to the nearest max
  or min value of the type, plus or minus 1. When the truncation
  happens, a warning is emitted
- Information schema table for sequences

After MDEV-31400, plugins are allowed to ask for retries when failing
initialisation. However, such failures also cause plugin system
variables to be deleted (plugin_variables_deinit()) before retrying
and are not re-added during retry.

We fix this by checking that if the plugin has requested a retry the
variables are not deleted. Because plugin_deinitialize() also calls
plugin_variables_deinit(), if the retry fails, the variables will
still be deleted.

Alternatives considered:

- remove the plugin_variables_deinit() from plugin_initialize() error
handling altogether. We decide to take a more conservative approach
here.

- re-add the system variables during retry. It is more complicated
than simply iterating over plugin->system_vars and call
my_hash_insert(). For example we will need to assign values to
the test_load field and extract more code from test_plugin_options(),
if that is possible.

followup for abcd23ad

it was able to enable --ssl-verify-server-cert if explicily requested,
now it can also disable it, if explicitly requested.

In case of failure, the something like the following is now printed:

Slave position:  file: binary.000004  position: 3647
Master position: file: binary.000004  position: 3647

binlog_space_limit is a variable in Percona server used to limit the total
size of all binary logs.

This implementation is based on code from Percona server 5.7.

In MariaDB we decided to call the variable max-binlog-total-size to be
similar to max-binlog-size. This makes it easier to find in the output
from 'mariadbd --help --verbose'). MariaDB will also support
binlog_space_limit for compatibility with Percona.

Some internal notes to explain implementation notes:

- When running MariaDB does not delete binary logs that are either
  used by slaves or have active xid that are not yet committed.

Some implementation notes:

- max-binlog-total-size is by default 0 (no limit).
- max-binlog-total-size can be changed without server restart.
- Binlog file sizes are checked on startup, or if
  max-binlog-total-size is set to a value > 0, not for every log write.
  The total size of all binary logs is cached and dynamically updated
  when updating the binary log on binary log rotation.
- max-binlog-total-size is checked against existing log files during
  serverstart, binlog rotation, FLUSH LOGS, when writing to binary log
  or when max-binlog-total-size changes value.
- Option --slave-connections-needed-for-purge with 1 as default added.
  This allows one to ensure that we do not delete binary logs if there
  is less than 'slave-connections-needed-for-purge' connected.
  Without this option max-binlog-total-size would potentially delete
  binlogs needed by slaves on server startup or when a slave disconnects
  as there are then no connected slaves to protect active binlogs.
- PURGE BINARY LOGS TO ... will be executed as if
  slave-connectitons-needed-for-purge would be zero. In other words
  it will do the purge even if there is no slaves connected. If there
  are connected slaves working on the logs, these will be protected.
- If binary log is on and max-binlog-total_size <> 0 then the status
  variable 'Binlog_disk_use' shows the current size of all old binary
  logs + the state of the current one.
- Removed test of strcmp(log_file_name, log_info.log_file_name) in
  purge_logs_before_date() as this is tested in can_purge_logs()
- To avoid expensive calls of log_in_use() we cache the result for the
  last log that is in use by a slave. Future calls to can_purge_logs()
  for this binary log will be quickly detected and false will be returned
  until a slave starts working on a new log.
- Note that after a binary log rotation caused by max_binlog_size,
  the last log will not be purged directly as it is still in use
  internally. The next binary log write will purge binlogs if needed.

Reviewer:Kristian Nielsen <knielsen@knielsen-hq.org>

libnet-ssleay-perl wasn't auto-detected

Revert "Deb: Stop shipping mariadb-plugin-spider separately, include in server"

This reverts commit 9945d482.

Instead of having a separate plugin, simply include Spider in the main
MariaDB Server package and let users manually enable on server installs
where they want to run it.