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".
The sys_var class has the deprecation_substitute member to mark the
deprecated variables. As it's set, the server produces warnings when
these variables are used. However, the plugin has no means to utilize
that functionality.
So, the PLUGIN_VAR_DEPRECATED flag is introduced to set the
deprecation_substitute with the empty string. A non-empty string can
make the warning more informative, but there's no nice way seen to
specify it, and not that needed at the moment.
Prototype change:
- virtual ha_rows records_in_range(uint inx, key_range *min_key,
- key_range *max_key)
+ virtual ha_rows records_in_range(uint inx, const key_range *min_key,
+ const key_range *max_key,
+ page_range *res)
The handler can ignore the page_range parameter. In the case the handler
updates the parameter, the optimizer can deduce the following:
- If previous range's last key is on the same block as next range's first
key
- If the current key range is in one block
- We can also assume that the first and last block read are cached!
This can be used for a better calculation of IO seeks when we
estimate the cost of a range index scan.
The parameter is fully implemented for MyISAM, Aria and InnoDB.
A separate patch will update handler::multi_range_read_info_const() to
take the benefits of this change and also remove the double
records_in_range() calls that are not anymore needed.
MDEV-19486 and one more similar bug appeared because handler::write_row() interface
welcomes to modify buffer by storage engine. But callers are not ready for that
thus bugs are possible in future.
handler::write_row():
handler::ha_write_row(): make argument const
Main reason was to make it easier to print the above structures in
a debugger. Additional benefits is that I was able to use same
defines for both structures, which simplifes some code.
Most of the code is just removing Alter_info:: and Alter_inplace_info::
from alter table flags.
Following renames was done:
HA_ALTER_FLAGS -> alter_table_operations
CHANGE_CREATE_OPTION -> ALTER_CHANGE_CREATE_OPTION
Alter_info::ADD_INDEX -> ALTER_ADD_INDEX
DROP_INDEX -> ALTER_DROP_INDEX
ADD_UNIQUE_INDEX -> ALTER_ADD_UNIQUE_INDEX
DROP_UNIQUE_INDEx -> ALTER_DROP_UNIQUE_INDEX
ADD_PK_INDEX -> ALTER_ADD_PK_INDEX
DROP_PK_INDEX -> ALTER_DROP_PK_INDEX
Alter_info:ALTER_ADD_COLUMN -> ALTER_PARSE_ADD_COLUMN
Alter_info:ALTER_DROP_COLUMN -> ALTER_PARSE_DROP_COLUMN
Alter_inplace_info::ADD_INDEX -> ALTER_ADD_NON_UNIQUE_NON_PRIM_INDEX
Alter_inplace_info::DROP_INDEX -> ALTER_DROP_NON_UNIQUE_NON_PRIM_INDEX
Other things:
- Added typedef alter_table_operatons for alter table flags
- DROP CHECK CONSTRAINT can now be done online
- Added checks for Aria tables in alter_table_online.test
- alter_table_flags now takes an ulonglong as argument.
- Don't support online operations if checksum option is used.
- sql_lex.cc doesn't add ALTER_ADD_INDEX if index is not created
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)
This was done to make it clear that a update_row() should not change the
row.
This was not done for handler::write_row() as this function still needs
to update auto_increment values in the row. This should at some point
be moved to handler::ha_write_row() after which write_row can also have
const arguments.
stat structure (from <sys/stat.h>) is conditionally defined
to have different layout and size depending on the defined macros.
The correct macro is defined in my_config.h, which means it MUST be
included first (or, at least before <features.h> - so, practically,
before including any system headers).
use the Alter_inplace_info::ALTER_COLUMN_OPTION flag if
field/column flags were altered.
change ha_example to use check_if_supported_inplace_alter() instead
of obsolete check_if_incompatible_data()
Fixed main.plugin, main-test_sql_discovery.plugin failures.
storage/example/ha_example.cc:
Issue a warning independently of DBUG status (needed for testing).
* update results
* don't force HA_CREATE_DELAY_KEY_WRITE on all temp tables,
(bad for CREATE ... LIKE) instead imply it in myisam/aria
* restore HA_ERR_TABLE_DEF_CHANGED in archive
* increase the default number of rwlock classes in P_S to fit all our rwlocks
includes:
* remove some remnants of "Bug#14521864: MYSQL 5.1 TO 5.5 BUGS PARTITIONING"
* introduce LOCK_share, now LOCK_ha_data is strictly for engines
* rea_create_table() always creates .par file (even in "frm-only" mode)
* fix a 5.6 bug, temp file leak on dummy ALTER TABLE
USING THE PLUGIN INTERFACE.
ISSUE: No support for floating-point plugin
system variables.
SOLUTION: Allowing plugins to define and expose floating-point
system variables of type double. MYSQL_SYSVAR_DOUBLE
and MYSQL_THDVAR_DOUBLE are added.
ISSUE: Fractional part of the def, min, max values of system
variables are ignored.
SOLUTION: Adding functions that are used to store the raw
representation of a double in the raw bits of unsigned
longlong in a way that the binary representation
remains the same.
