This patch is the result of running
run-clang-tidy -fix -header-filter=.* -checks='-*,modernize-use-equals-default' .
Code style changes have been done on top. The result of this change
leads to the following improvements:
1. Binary size reduction.
* For a -DBUILD_CONFIG=mysql_release build, the binary size is reduced by
~400kb.
* A raw -DCMAKE_BUILD_TYPE=Release reduces the binary size by ~1.4kb.
2. Compiler can better understand the intent of the code, thus it leads
to more optimization possibilities. Additionally it enabled detecting
unused variables that had an empty default constructor but not marked
so explicitly.
Particular change required following this patch in sql/opt_range.cc
result_keys, an unused template class Bitmap now correctly issues
unused variable warnings.
Setting Bitmap template class constructor to default allows the compiler
to identify that there are no side-effects when instantiating the class.
Previously the compiler could not issue the warning as it assumed Bitmap
class (being a template) would not be performing a NO-OP for its default
constructor. This prevented the "unused variable warning".
- Add `replicate_rewrite_db` status variable, that may accept comma
separated key-value pairs.
- Note that option `OPT_REPLICATE_REWRITE_DB` already existed in `mysqld.h`
from this commit 23d8586dbf
Reviewer:Brandon Nesterenko <brandon.nesterenko@mariadb.com>
New Feature:
============
Extend mariadb-binlog command-line tool to allow for filtering
events using GTID domain and server ids. The functionality mimics
that of a replica server’s DO_DOMAIN_IDS, IGNORE_DOMAIN_IDS, and
IGNORE_SERVER_IDS from CHANGE MASTER TO. For completeness, this
patch additionally adds the option --do-server-ids as an alias for
--server-id, which now accepts a list of server ids instead of a
single one.
Example usage:
mariadb-binlog --do-domain-ids=2,3,4 --do-server-ids=1,3
master-bin.000001
Functional Notes:
1. --do-domain-ids cannot be combined with --ignore-domain-ids
2. --do-server-ids cannot be combined with --ignore-server-ids
3. A domain id filter can be combined with a server id filter
4. When any new filter options are combined with the
--gtid-strict-mode option, events from excluded domains/servers are
not validated.
5. Domain/server id filters can be combined with GTID ranges (i.e.
specifications of --start-position and --stop-position). However,
because the --stop-position option implicitly undertakes filtering
to only output events within its range of domains, when combined
with --do-domain-ids or --ignore-domain-ids, output will consist of
the intersection between the filters. Specifically, with
--do-domain-ids and --stop-position, only events with domain ids
present in both argument lists will be output. Conversely, with
--ignore-domain-ids and --stop-position, only events with domain ids
present in the --stop-position and absent from the
--ignore-domain-ids options will be output.
Reviewed By
============
Andrei Elkin <andrei.elkin@mariadb.com>
Problem:
========
When using mariadb-binlog with --raw and --stop-never, events from
the master's currently active log file should be written to their
respective log file specified by --result-file, and shown on-disk.
There is a bug where mariadb-binlog does not flush the result file
to disk when new events are received
Solution:
========
Add a function call to flush mariadb-binlog’s result file after
receiving an event in --raw mode.
Reviewed By:
============
Andrei Elkin <andrei.elkin@mariadb.com>
This commit implements two phase binloggable ALTER.
When a new
@@session.binlog_alter_two_phase = YES
ALTER query gets logged in two parts, the START ALTER and the COMMIT
or ROLLBACK ALTER. START Alter is written in binlog as soon as
necessary locks have been acquired for the table. The timing is
such that any concurrent DML:s that update the same table are either
committed, thus logged into binary log having done work on the old
version of the table, or will be queued for execution on its new
version.
The "COMPLETE" COMMIT or ROLLBACK ALTER are written at the very point
of a normal "single-piece" ALTER that is after the most of
the query work is done. When its result is positive COMMIT ALTER is
written, otherwise ROLLBACK ALTER is written with specific error
happened after START ALTER phase.
Replication of two-phase binloggable ALTER is
cross-version safe. Specifically the OLD slave merely does not
recognized the start alter part, still being able to process and
memorize its gtid.
Two phase logged ALTER is read from binlog by mysqlbinlog to produce
BINLOG 'string', where 'string' contains base64 encoded
Query_log_event containing either the start part of ALTER, or a
completion part. The Query details can be displayed with `-v` flag,
similarly to ROW format events. Notice, mysqlbinlog output containing
parts of two-phase binloggable ALTER is processable correctly only by
binlog_alter_two_phase server.
@@log_warnings > 2 can reveal details of binlogging and slave side
processing of the ALTER parts.
The current commit also carries fixes to the following list of
reported bugs:
MDEV-27511, MDEV-27471, MDEV-27349, MDEV-27628, MDEV-27528.
Thanks to all people involved into early discussion of the feature
including Kristian Nielsen, those who helped to design, implement and
test: Sergei Golubchik, Andrei Elkin who took the burden of the
implemenation completion, Sujatha Sivakumar, Brandon
Nesterenko, Alice Sherepa, Ramesh Sivaraman, Jan Lindstrom.
New Feature:
===========
This commit extends the mariadb-binlog capabilities to allow events
to be filtered by GTID ranges. More specifically, the
--start-position and --stop-position arguments have been extended to
accept values formatted as a list of GTID positions, e.g.
--start-position=0-1-0,1-2-55. The following specific capabilities
are addressed:
1) GTIDs can be used to filter results on local binlog files
2) GTIDs can be used to filter results from remote servers
3) Implemented --gtid-strict-mode that ensures the GTID event
stream in each domain is monotonically increasing
4) Added new level of verbosity in mysqlbinlog -vvv to print
additional diagnostic information/warnings about invalid GTID
states
5) For a given GTID range, its start and stop position parameters
aim to mimic the behaviors of
CHANGE MASTER TO MASTER_USE_GTID=slave_pos and
START SLAVE UNTIL master_gtid_pos=<GTID>, respectively. In
particular, the start-position list expresses a gtid state of
the server, similarly to how @@global.gtid_slave_pos expresses
the gtid state of a slave server when connecting to a master
with MASTER_USE_GTID=slave_pos.
The GTID start-position list is exclusive and the
stop-position list is inclusive. This allows users to receive
events strictly after those that they already have, and is
useful in cases of point in (logical) time recovery including
1) events were received out of order and should be re-sent, or
2) specifying the gtid state of a slave to get events newer
than their current state. If a seq_no is 0 for start-position,
it means to include the entirety of the domain. If a seq_no is
0 for stop-position, it means to exclude all events from that
domain. The GTIDs provided in a start position argument must
match with the GTID state of the first processed log (i.e.
those listed in the Gtid_list event). If a stop position is
provided, the events that are output are limited to only those
with domain ids listed in the argument. When specifying
combinations of start and stop positions, the following
behaviors are expected:
[--start-position without --stop-position]: Events that have domain
ids in the start position are output if their seq_no occurs after
the respective start position. Events with domain ids that are
unspecified in the start position list are also output. Note that if
the Gtid_list event of the first binary log is populated (i.e.
non-empty), each domain in the Gtid_list must be present in the
start-position list with a seq_no at or after the listed value.
This behavior mimics how a slave only processes events after the
state provided by @@global.gtid_slave_pos when connecting to a
master with CHANGE MASTER TO MASTER_USE_GTID=slave_pos.
[--stop-position without --start-position]: Output is limited to
only events with both 1) domain ids that are present in the given
stop position list and 2) seq_nos that are less than or equal to
their respective stop GTID. Once all GTIDs in the stop position
list have been processed, the program will stop processing log
files. This behavior mimics how
START SLAVE UNTIL master_gtid_pos=<G>
has a slave only process events with domain ids present in G with
their seq_nos at or before the respective gtid.
[--start-position and --stop-position]: Output consists of the
intersection between the events permitted by both the start and stop
position rules. More concretely, the output can be defined by a
union of the following rules:
1. For domains which exist in both the start and stop position
lists, the events which exist in-between these positions
(exclusive start, inclusive stop) are output
2. For all other events, the rules of
[--stop-position without --start-position] are followed
This is due to the implicit filtering within each individual rule.
Even though the start position rule always includes events from
unspecified domains, the stop position rule takes precedence because
it always excludes events from unspecified domains. In other words,
events which the start position rule would have included would then
always be excluded by the stop position rule.
[neither --start-position nor --stop-position]: Events are not
omitted based on GTID positioning; however, --gtid-strict-mode and
-vvv can still analyze gtid correctness for warning and error
reporting.
[repeated specification of --start-position or --stop-position]:
Subsequent specifications of start and stop positions completely
override previous ones. E.g., if invoked as
mysqlbinlog --start-position=<G1> --start-position=<G2> ...
All GTIDs specified in G1 are ignored and only those specified in G2
are used for the start position.
A few additional notes:
1) this commit squashes together the commits:
f4319661120e-78a9d49907ba
2) Changed rpl.rpl_blackhole_row_annotate test because it has
out of order GTIDs in its binlog, so I added
--skip-gtid-strict-mode
3) After all binlog events have been written, the session server
id and domain id are reset to their values in the global state
Reviewed By:
===========
Andrei Elkin: <andrei.elkin@mariadb.com>
https://jira.mariadb.org/browse/MDEV-26221
my_sys DYNAMIC_ARRAY and DYNAMIC_STRING inconsistancy
The DYNAMIC_STRING uses size_t for sizes, but DYNAMIC_ARRAY used uint.
This patch adjusts DYNAMIC_ARRAY to use size_t like DYNAMIC_STRING.
As the MY_DIR member number_of_files is copied from a DYNAMIC_ARRAY,
this is changed to be size_t.
As MY_TMPDIR members 'cur' and 'max' are copied from a DYNAMIC_ARRAY,
these are also changed to be size_t.
The lists of plugins and stored procedures use DYNAMIC_ARRAY,
but their APIs assume a size of 'uint'; these are unchanged.
This fixed the MySQL bug# 20338 about misuse of double underscore
prefix __WIN__, which was old MySQL's idea of identifying Windows
Replace it by _WIN32 standard symbol for targeting Windows OS
(both 32 and 64 bit)
Not that connect storage engine is not fixed in this patch (must be
fixed in "upstream" branch)
This change is to get rid of randomly failing tests, especially those
that reads random position of the binary log. From looking at the logs
it's clear that some failures is because of a read char (with value >= 128)
is converted to a big long value. Using uchar everywhere makes this much
less likely to happen.
Another benefit is that a lot of cast of char to uchar could be removed.
Other things:
- Removed some extra space before '=' and '+=' in assignments
- Fixed indentations and lines > 80 characters
- Replace '16' with 'element_size' (from class definition) in
Gtid_list_log_event()
The --help comment for the --base64-output option in
mysqlbinlog was hard to decipher. This quick patch aims
to refine it.
Reviewed By:
==========
Andrei Elkin: <andrei.elkin@mariadb.com>
Problem:
=======
The ALWAYS option of the mariadb-binlog --base64-output flag
formats its output incorrectly. This option is deprecated, and
MySQL 8.0 has removed it entirely.
Solution:
========
Adhere to MySQL and remove this option from MariaDB.
Behavioral Changes:
==================
Use Case: ./mariadb-binlog --base64-output
Previous Behavior: Sets base64-output mode to always
New Behavior: Error message indicating incomplete argument
Use Case: ./mariadb-binlog --base64-output=always
Previous Behavior: Sets base64-output mode to always
New Behavior: Error message indicating invalid argument value
Reviewed By:
==========
Andrei Elkin: <andrei.elkin@mariadb.com>
Problem:
=======
MariaDB's command line utilities (e.g., mysql,
mysqldump, etc) silently ignore connection
property options (e.g., --port and --socket)
when protocol is not explicitly set via the
command-line for localhost connections.
Fix:
===
If connection properties are specified without a
protocol, override the protocol to be consistent.
For example, if --port is specified, automatically
set protocol=tcp.
Caveats:
=======
* When multiple connection properties are
specified, nothing is overridden
* If protocol is is set via the command-line,
its value is used
Reviewers:
========
Sergei Golubchik <serg@mariadb.com>
Vladislav Vaintroub <wlad@mariadb.com>
One should not change the program arguments!
This change also reduces warnings from the icc compiler.
Almost all changes are just syntax changes (adding const to
'get_one_option function' declarations).
Other changes:
- Added a few cast of 'argument' from 'const char*' to 'char *'. This
was mainly in calls to 'external' functions we don't have control of.
- Ensure that all reset of 'password command line argument' are similar.
(In almost all cases it was just adding a comment and a cast)
- In mysqlbinlog.cc and mysqld.cc there was a few cases that changed
the command line argument. These places where changed to instead allocate
the option in a MEM_ROOT to avoid changing the argument. Some of this
code was changed to ensure that different programs did parsing the
same way. Added a test case for the changes in mysqlbinlog.cc
- Changed a few variables that took their value from command line options
from 'char *' to 'const char *'.
(This commit is for 10.3 and upper branches)
In case of a pattern of non-STMT_END-marked Rows-log-event (A) followed by
a STMT_END marked one (B) mysqlbinlog mixes up the base64 encoded rows events
with their pseudo sql representation produced by the verbose option:
BINLOG '
base64 encoded data for A
### verbose section for A
base64 encoded data for B
### verbose section for B
'/*!*/;
In effect the produced BINLOG '...' query is not valid and is rejected with the error.
Examples of this way malformed BINLOG could have been found in binlog_row_annotate.result
that gets corrected with the patch.
The issue is fixed with introduction an auxiliary IO_CACHE to hold on the verbose
comments until the terminal STMT_END event is found. The new cache is emptied
out after two pre-existing ones are done at that time.
The correctly produced output now for the above case is as the following:
BINLOG '
base64 encoded data for A
base64 encoded data for B
'/*!*/;
### verbose section for A
### verbose section for B
Thanks to Alexey Midenkov for the problem recognition and attempt to tackle,
and to Venkatesh Duggirala who produced a patch for the upstream whose
idea is exploited here, as well as to MDEV-23077 reporter LukeXwang who
also contributed a piece of a patch aiming at this issue.
(This commit is exclusively for 10.2 branch. Do not merge it to 10.3)
In case of a pattern of non-STMT_END-marked Rows-log-event (A) followed by
a STMT_END marked one (B) mysqlbinlog mixes up the base64 encoded rows events
with their pseudo sql representation produced by the verbose option:
BINLOG '
base64 encoded data for A
### verbose section for A
base64 encoded data for B
### verbose section for B
'/*!*/;
In effect the produced BINLOG '...' query is not valid and is rejected with the error.
Examples of this way malformed BINLOG could have been found in binlog_row_annotate.result
that gets corrected with the patch.
The issue is fixed with introduction an auxiliary IO_CACHE to hold on the verbose
comments until the terminal STMT_END event is found. The new cache is emptied
out after two pre-existing ones are done at that time.
The correctly produced output now for the above case is as the following:
BINLOG '
base64 encoded data for A
base64 encoded data for B
'/*!*/;
### verbose section for A
### verbose section for B
Thanks to Alexey Midenkov for the problem recognition and attempt to tackle,
and to Venkatesh Duggirala who produced a patch for the upstream whose
idea is exploited here, as well as to MDEV-23077 reporter LukeXwang who
also contributed a piece of a patch aiming at this issue.
Stop linking plugins to the server executable on Windows.
Instead, extract whole server functionality into a large DLL, called
server.dll. Link both plugins, and small server "stub" exe to it.
This eliminates plugin dependency on the name of the server executable.
It also reduces the size of the packages (since tiny mysqld.exe
and mariadbd.exe are now both linked to one big DLL)
Also, simplify the functionality of exporing all symbols from selected
static libraries. Rely on WINDOWS_EXPORT_ALL_SYMBOLS, rather than old
self-backed solution.
fix compile error
replace GetProcAddress(GetModuleHandle(NULL), "variable_name")
for server exported data with actual variable names.
Runtime loading was never required,was error prone
, since symbols could be missing at runtime, and now it actually failed,
because we do not export symbols from executable anymore, but from a shared
library
This did require a MYSQL_PLUGIN_IMPORT decoration for the plugin,
but made the code more straightforward, and avoids missing symbols at
runtime (as mentioned before).
The audit plugin is still doing some dynamic loading, as it aims to work
cross-version. Now it won't work cross-version on Windows, as it already
uses some symbols that are *not* dynamically loaded, e.g fn_format
and those symbols now exported from server.dll , when earlier they were
exported by mysqld.exe
Windows, fixes for storage engine plugin loading
after various rebranding stuff
Create server.dll containing functionality of the whole server
make mariadbd.exe/mysqld.exe a stub that is only calling mysqld_main()
fix build
Cherry-pick the commits the mysql and some changes.
WL#4618 RBR: extended table metadata in the binary log
This patch extends Table Map Event. It appends some new fields for
more metadata. The new metadata includes:
- Signedness of Numberic Columns
- Character Set of Character Columns and Binary Columns
- Column Name
- String Value of SET Columns
- String Value of ENUM Columns
- Primary Key
- Character Set of SET Columns and ENUM Columns
- Geometry Type
Some of them are optional, the patch introduces a GLOBAL system
variable to control it. It is binlog_row_metadata.
- Scope: GLOBAL
- Dynamic: Yes
- Type: ENUM
- Values: {NO_LOG, MINIMAL, FULL}
- Default: NO_LOG
Only Signedness, character set and geometry type are logged if it is MINIMAL.
Otherwise all of them are logged.
Also add a binlog_type_info() to field, So that we can have extract
relevant binlog info from field.
- Added mariadb-# to load_default_groups to all mariadb-# scripts and
mariadb-binaries.
- Added mariadbd and mariadbd-"version" to load_default_groups for the
mysqld/mariadb server
- Added mariadb-client to load_default_groups for the mysql/mariadb client
Other things
- Ignored mysql-test/lib/My/SafeProcess/wsrep_check_version
- mysql_install_db will now automatically detect if run from srcdir
Server and command line tools now support option --tls_version to specify the
TLS version between client and server. Valid values are TLSv1.0, TLSv1.1, TLSv1.2, TLSv1.3
or a combination of them. E.g.
--tls_version=TLSv1.3
--tls_version=TLSv1.2,TLSv1.3
In case there is a gap between versions, the lowest version will be used:
--tls_version=TLSv1.1,TLSv1.3 -> Only TLSv1.1 will be available.
If the used TLS library doesn't support the specified TLS version, it will use
the default configuration.
Limitations:
SSLv3 is not supported. The default configuration doesn't support TLSv1.0 anymore.
TLSv1.3 protocol currently is only supported by OpenSSL 1.1.0 (client and server) and
GnuTLS 3.6.5 (client only).
Overview of TLS implementations and protocols
Server:
+-----------+-----------------------------------------+
| Library | Supported TLS versions |
+-----------+-----------------------------------------+
| WolfSSL | TLSv1.1, TLSv1,2 |
+-----------+-----------------------------------------+
| OpenSSL | (TLSv1.0), TLSv1.1, TLSv1,2, TLSv1.3 |
+-----------+-----------------------------------------+
| LibreSSL | (TLSv1.0), TLSv1.1, TLSv1,2, TLSv1.3 |
+-----------+-----------------------------------------+
Client (MariaDB Connector/C)
+-----------+-----------------------------------------+
| Library | Supported TLS versions |
+-----------+-----------------------------------------+
| GnuTLS | (TLSv1.0), TLSv1.1, TLSv1.2, TLSv1.3 |
+-----------+-----------------------------------------+
| Schannel | (TLSv1.0), TLSv1.1, TLSv1.2 |
+-----------+-----------------------------------------+
| OpenSSL | (TLSv1.0), TLSv1.1, TLSv1,2, TLSv1.3 |
+-----------+-----------------------------------------+
| LibreSSL | (TLSv1.0), TLSv1.1, TLSv1,2, TLSv1.3 |
+-----------+-----------------------------------------+
Problem:
========
The mysqlbinlog tool is leaking memory, causing failures in various tests when
compiling and testing with AddressSanitizer or LeakSanitizer like this:
cmake -DCMAKE_BUILD_TYPE=Debug -DWITH_ASAN:BOOL=ON /path/to/source
make -j$(nproc)
cd mysql-test
ASAN_OPTIONS=abort_on_error=1 ./mtr --parallel=auto
Analysis:
=========
Two types of leaks were observed during above execution.
1) Leak in Log_event::read_log_event(char const*, unsigned int, char const**,
Format_description_log_event const*, char)
File: sql/log_event.cc:2150
For all row based replication events the memory which is allocated during
read_log_event is not freed after the event is processed. The event specific
memory has to be retained only when flashback option is enabled with
mysqlbinlog tool. In this case all the events are retained till the end
statement is received and they are processed in reverse order and they are
destroyed. But in the existing code all events are retained irrespective of
flashback mode. Hence the memory leaks are observed.
2) read_remote_annotate_event(unsigned char*, unsigned long, char const**)
File: client/mysqlbinlog.cc:194
In general the Annotate event is not printed immediately because all
subsequent rbr-events can be filtered away. Instead it will be printed
together with the first not filtered away Table map or the last rbr will be
processed. While reading remote annotate events memory is allocated for event
buffer and event's temp_buf is made to point to the allocated buffer as shown
below. The TRUE flag is used for doing proper cleanup using free_temp_buf().
i.e at the time of deletion of annotate event its destructor takes care of
clearing the temp_buf.
/*
Ensure the event->temp_buf is pointing to the allocated buffer.
(TRUE = free temp_buf on the event deletion)
*/
event->register_temp_buf((char*)event_buf, TRUE);
But existing code does the following when it receives a remote annotate_event.
if (remote_opt)
ev->temp_buf= 0;
That is code immediately sets temp_buf=0, because of which free_temp_buf()
call will return empty handed as it has lost the reference to the allocated
temporary buffer. This results in memory leak
Fix:
====
1) If not in flashback mode, destroy the memory for events once they are
processed.
2) Remove the ev->temp_buf=0 code for remote option. Let the proper cleanup to
be done as part of free_temp_buf().
Problem:
========
The mysqlbinlog tool is leaking memory, causing failures in various tests when
compiling and testing with AddressSanitizer or LeakSanitizer like this:
cmake -DCMAKE_BUILD_TYPE=Debug -DWITH_ASAN:BOOL=ON /path/to/source
make -j$(nproc)
cd mysql-test
ASAN_OPTIONS=abort_on_error=1 ./mtr --parallel=auto rpl.rpl_row_mysqlbinlog
CURRENT_TEST: rpl.rpl_row_mysqlbinlog
Direct leak of 112 byte(s) in 1 object(s) allocated from:
#0 0x4eff87 in __interceptor_malloc (/dev/shm/5.5/client/mysqlbinlog+0x4eff87)
#1 0x60eaab in my_malloc /mariadb/5.5/mysys/my_malloc.c:41:10
#2 0x5300dd in Log_event::read_log_event(char const*, unsigned int, char const**,
Format_description_log_event const*, char) /mariadb/5.5/sql/log_event.cc:1568:
#3 0x564a9c in dump_remote_log_entries(st_print_event_info*, char const*)
/mariadb/5.5/client/mysqlbinlog.cc:1978:17
Analysis:
========
'mysqlbinlog' tool is being used to read binary log events from a remote server.
While reading binary log, if a fake rotate event is found following actions are
taken.
If 'to-last-log' option is specified, then fake rotate event is processed.
In the absence of 'to-last-log' skip the fake rotate event.
In this skipped case the fake rotate event object is not getting cleaned up
resulting in memory leak.
Fix:
===
Cleanup the fake rotate event.
This issues is already fixed in MariaDB 10.0.23 and higher versions as part of
commit c3018b0ff4
The MDEV-17262 commit 26432e49d3
was skipped. In Galera 4, the implementation would seem to require
changes to the streaming replication.
In the tests archive.rnd_pos main.profiling, disable_ps_protocol
for SHOW STATUS and SHOW PROFILE commands until MDEV-18974
has been fixed.
There were two newly enabled warnings:
1. cast for a function pointers. Affected sql_analyse.h, mi_write.c
and ma_write.cc, mf_iocache-t.cc, mysqlbinlog.cc, encryption.cc, etc
2. memcpy/memset of nontrivial structures. Fixed as:
* the warning disabled for InnoDB
* TABLE, TABLE_SHARE, and TABLE_LIST got a new method reset() which
does the bzero(), which is safe for these classes, but any other
bzero() will still cause a warning
* Table_scope_and_contents_source_st uses `TABLE_LIST *` (trivial)
instead of `SQL_I_List<TABLE_LIST>` (not trivial) so it's safe to
bzero now.
* added casts in debug_sync.cc and sql_select.cc (for JOIN)
* move assignment method for MDL_request instead of memcpy()
* PARTIAL_INDEX_INTERSECT_INFO::init() instead of bzero()
* remove constructor from READ_RECORD() to make it trivial
* replace some memcpy() with c++ copy assignments
The problem was originally stated in
http://bugs.mysql.com/bug.php?id=82212
The size of an base64-encoded Rows_log_event exceeds its
vanilla byte representation in 4/3 times.
When a binlogged event size is about 1GB mysqlbinlog generates
a BINLOG query that can't be send out due to its size.
It is fixed with fragmenting the BINLOG argument C-string into
(approximate) halves when the base64 encoded event is over 1GB size.
The mysqlbinlog in such case puts out
SET @binlog_fragment_0='base64-encoded-fragment_0';
SET @binlog_fragment_1='base64-encoded-fragment_1';
BINLOG @binlog_fragment_0, @binlog_fragment_1;
to represent a big BINLOG.
For prompt memory release BINLOG handler is made to reset the BINLOG argument
user variables in the middle of processing, as if @binlog_fragment_{0,1} = NULL
is assigned.
Notice the 2 fragments are enough, though the client and server still may
need to tweak their @@max_allowed_packet to satisfy to the fragment
size (which they would have to do anyway with greater number of
fragments, should that be desired).
On the lower level the following changes are made:
Log_event::print_base64()
remains to call encoder and store the encoded data into a cache but
now *without* doing any formatting. The latter is left for time
when the cache is copied to an output file (e.g mysqlbinlog output).
No formatting behavior is also reflected by the change in the meaning
of the last argument which specifies whether to cache the encoded data.
Rows_log_event::print_helper()
is made to invoke a specialized fragmented cache-to-file copying function
which is
copy_cache_to_file_wrapped()
that takes care of fragmenting also optionally wraps encoded
strings (fragments) into SQL stanzas.
my_b_copy_to_file()
is refactored to into my_b_copy_all_to_file(). The former function
is generalized
to accepts more a limit argument to constraint the copying and does
not reinitialize anymore the cache into reading mode.
The limit does not do any effect on the fully read cache.
