Modern compilers (such as GCC 8) emit warnings that the
'register' keyword is deprecated and not valid C++17.
Let us remove most use of the 'register' keyword.
Code in 'extra/' is not touched.
Handle string length as size_t, consistently (almost always:))
Change function prototypes to accept size_t, where in the past
ulong or uint were used. change local/member variables to size_t
when appropriate.
This fix excludes rocksdb, spider,spider, sphinx and connect for now.
Code in QUICK_RANGE_SELECT::init_ror_merged_scan() could theoretically
have caused crashes if this was ever called from an update or delete
This also found a bug in the vcol/range.result. file.
In the function make_sortkey a tmp buffer was defined and in the absence of
param->tmp_buffer, tmp buffer used the sort_keys buffer. sort_keys buffer
has a length defined in sort_field->length, while param->tmp_buffer is
stored in param->rec_length. Make sure to use the appropriate length
based on which buffer we are using otherwise we'll overflow.
Also added a type cast to size_t during the calculation of the sort keys
buffer size to avoid an oveflow if the buffer size exceeds 32 bits.
This fixes MDEV-7742 and MDEV-8305 (Allow user to specify if stored
procedures should be logged in the slow and general log)
New functionality:
- Added new variables log_slow_disable_statements and log_disable_statements
that can be used to disable logging of certain queries to slow and
general log. Currently supported options are 'admin', 'call', 'slave'
and 'sp'.
Defaults are as before. Only 'sp' (stored procedure statements) is
disabled for slow and general_log.
- Slow log to files now includes the following new information:
- When logging stored procedure statements the name of stored
procedure is logged.
- Number of created tmp_tables, tmp_disk_tables and the space used
by temporary tables.
- When logging 'call', the logged status now contains the sum of all
included statements. Before only 'time' was correct.
- Added filsort_priority_queue as an option for log_slow_filter (this
variable existed before, but was not exposed)
- Added support for BIT types in my_getopt()
Mapped some old variables to bitmaps (old variables can still be used)
- Variable 'log_queries_not_using_indexes' is mapped to
log_slow_filter='not_using_index'
- Variable 'log_slow_slave_statements' is mapped to
log_slow_disabled_statements='slave'
- Variable 'log_slow_admin_statements' is mapped to
log_slow_disabled_statements='admin'
- All the above variables are changed to session variables from global
variables
Other things:
- Simplified LOGGER::log_command. We don't need to check for super if
OPTION_LOG_OFF is set as this flag can only be set if one is a super
user.
- Removed some setting of enable_slow_log as it's guaranteed to be set by
mysql_parse()
- mysql_admin_table() now sets thd->enable_slow_log
- Added prepare_logs_for_admin_command() to reset thd->enable_slow_log if
needed.
- Added new functions to store, restore and add slow query status
- Added new functions to store and restore query start time
- Reorganized Sub_statement_state according to types
- Added code in dispatch_command() to ensure that
thd->reset_for_next_command() is always called for a query.
- Added thd->last_sql_command to simplify checking of what was the type
of the last command. Needed when logging to slow log as lex->sql_command
may have changed before slow logging is called.
- Moved QPLAN_TMP_... to where status for tmp tables are updated
- Added new THD variable, affected_rows, to be able to correctly log
number of affected rows to slow log.
- Added sql/mariadb.h file that should be included first by files in sql
directory, if sql_plugin.h is not used (sql_plugin.h adds SHOW variables
that must be done before my_global.h is included)
- Removed a lot of include my_global.h from include files
- Removed include's of some files that my_global.h automatically includes
- Removed duplicated include's of my_sys.h
- Replaced include my_config.h with my_global.h
These self references were previously used to avoid having to check the
IO_CACHE's type. However, a benchmark shows that on x86 5930k stock,
the type comparison is marginally faster than the double pointer dereference.
For 40 billion my_b_tell calls, the difference is .1 seconds in favor of performing the
type check. (Basically there is no measurable difference)
To prevent bugs from copying the structure using the equals(=) operator,
and having to do the bookkeeping manually, remove these "convenience"
variables.
The sole purpose of handlerton::release_temporary_latches and its wrapper
function was to release the InnoDB adaptive hash index latch
(btr_search_latch).
When the btr_search_latch was split into an array of latches
in MySQL 5.7.8 as part of the Oracle Bug#20985298 fix, the "caching"
of the latch across storage engine API calls was removed. As part of that,
the function trx_search_latch_release_if_reserved() was changed to an
assertion and the function trx_reserve_search_latch_if_not_reserved()
was removed, and handlerton::release_temporary_latches() practically
became a no-op.
Note: MDEV-12121 replaced the function
trx_search_latch_release_if_reserved()
with the more appropriately named macro trx_assert_no_search_latch().
Benefits of this patch:
- Removed a lot of calls to strlen(), especially for field_string
- Strings generated by parser are now const strings, less chance of
accidently changing a string
- Removed a lot of calls with LEX_STRING as parameter (changed to pointer)
- More uniform code
- Item::name_length was not kept up to date. Now fixed
- Several bugs found and fixed (Access to null pointers,
access of freed memory, wrong arguments to printf like functions)
- Removed a lot of casts from (const char*) to (char*)
Changes:
- This caused some ABI changes
- lex_string_set now uses LEX_CSTRING
- Some fucntions are now taking const char* instead of char*
- Create_field::change and after changed to LEX_CSTRING
- handler::connect_string, comment and engine_name() changed to LEX_CSTRING
- Checked printf() related calls to find bugs. Found and fixed several
errors in old code.
- A lot of changes from LEX_STRING to LEX_CSTRING, especially related to
parsing and events.
- Some changes from LEX_STRING and LEX_STRING & to LEX_CSTRING*
- Some changes for char* to const char*
- Added printf argument checking for my_snprintf()
- Introduced null_clex_str, star_clex_string, temp_lex_str to simplify
code
- Added item_empty_name and item_used_name to be able to distingush between
items that was given an empty name and items that was not given a name
This is used in sql_yacc.yy to know when to give an item a name.
- select table_name."*' is not anymore same as table_name.*
- removed not used function Item::rename()
- Added comparision of item->name_length before some calls to
my_strcasecmp() to speed up comparison
- Moved Item_sp_variable::make_field() from item.h to item.cc
- Some minimal code changes to avoid copying to const char *
- Fixed wrong error message in wsrep_mysql_parse()
- Fixed wrong code in find_field_in_natural_join() where real_item() was
set when it shouldn't
- ER_ERROR_ON_RENAME was used with extra arguments.
- Removed some (wrong) ER_OUTOFMEMORY, as alloc_root will already
give the error.
TODO:
- Check possible unsafe casts in plugin/auth_examples/qa_auth_interface.c
- Change code to not modify LEX_CSTRING for database name
(as part of lower_case_table_names)
Filesort temporarily changes read_set to be tmp_set and marks only
fields needed for filesort. Add an assert to ensure that it doesn't
overwrite the old value of tmp_set, that is that read_set was *not*
already tmp_set when filesort was invoked.
Fix sql_update.cc that was was doing exactly that - changing read_set to
tmp_set, configuring tmp_set for keyread, and then invoking filesort.
Found and fixed 2 problems:
- Filesort addon fields didn't mark virtual columns properly
- multi-range-read calculated vcol bitmap but was not using it.
This caused wrong vcol field to be calculated on read, which caused the assert.
In file sql/filesort.cc,when merge_buffers() is called then
- queue_remove(&queue,0) is called
- For the function queue_remove there is assertion states that the element to be removed should have index >=1
- this is causing the assertion to fail.
Fixed by removing the top element.
This fixes a bug where handler::read_range_first (for example)
needed to compare vcol values that were not calculated yet.
As a bonus it fixes few cases where vcols were calculated twice
