Step#1: fixing the return type of strnxfrm() from size_t to this structure:
typedef struct
{
size_t m_output_length;
size_t m_source_length_used;
uint m_warnings;
} my_strnxfrm_ret_t;
The `Item` class methods `get_copy()`, `build_clone()`, and `clone_item()`
face an issue where they may be defined in a descendant class
(e.g., `Item_func`) but not in a further descendant (e.g., `Item_func_child`).
This can lead to scenarios where `build_clone()`, when operating on an
instance of `Item_func_child` with a pointer to the base class (`Item`),
returns an instance of `Item_func` instead of `Item_func_child`.
Since this limitation cannot be resolved at compile time, this commit
introduces runtime type checks for the copy/clone operations.
A debug assertion will now trigger in case of a type mismatch.
`get_copy()`, `build_clone()`, and `clone_item()` are no more virtual,
but virtual `do_get_copy()`, `do_build_clone()`, and `do_clone_item()`
are added to the protected section of the class `Item`.
Additionally, const qualifiers have been added to certain methods
to enhance code reliability.
Reviewer: Oleksandr Byelkin <sanja@mariadb.com>
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")});
Changes:
- To detect automatic strlen() I removed the methods in String that
uses 'const char *' without a length:
- String::append(const char*)
- Binary_string(const char *str)
- String(const char *str, CHARSET_INFO *cs)
- append_for_single_quote(const char *)
All usage of append(const char*) is changed to either use
String::append(char), String::append(const char*, size_t length) or
String::append(LEX_CSTRING)
- Added STRING_WITH_LEN() around constant string arguments to
String::append()
- Added overflow argument to escape_string_for_mysql() and
escape_quotes_for_mysql() instead of returning (size_t) -1 on overflow.
This was needed as most usage of the above functions never tested the
result for -1 and would have given wrong results or crashes in case
of overflows.
- Added Item_func_or_sum::func_name_cstring(), which returns LEX_CSTRING.
Changed all Item_func::func_name()'s to func_name_cstring()'s.
The old Item_func_or_sum::func_name() is now an inline function that
returns func_name_cstring().str.
- Changed Item::mode_name() and Item::func_name_ext() to return
LEX_CSTRING.
- Changed for some functions the name argument from const char * to
to const LEX_CSTRING &:
- Item::Item_func_fix_attributes()
- Item::check_type_...()
- Type_std_attributes::agg_item_collations()
- Type_std_attributes::agg_item_set_converter()
- Type_std_attributes::agg_arg_charsets...()
- Type_handler_hybrid_field_type::aggregate_for_result()
- Type_handler_geometry::check_type_geom_or_binary()
- Type_handler::Item_func_or_sum_illegal_param()
- Predicant_to_list_comparator::add_value_skip_null()
- Predicant_to_list_comparator::add_value()
- cmp_item_row::prepare_comparators()
- cmp_item_row::aggregate_row_elements_for_comparison()
- Cursor_ref::print_func()
- Removes String_space() as it was only used in one cases and that
could be simplified to not use String_space(), thanks to the fixed
my_vsnprintf().
- Added some const LEX_CSTRING's for common strings:
- NULL_clex_str, DATA_clex_str, INDEX_clex_str.
- Changed primary_key_name to a LEX_CSTRING
- Renamed String::set_quick() to String::set_buffer_if_not_allocated() to
clarify what the function really does.
- Rename of protocol function:
bool store(const char *from, CHARSET_INFO *cs) to
bool store_string_or_null(const char *from, CHARSET_INFO *cs).
This was done to both clarify the difference between this 'store' function
and also to make it easier to find unoptimal usage of store() calls.
- Added Protocol::store(const LEX_CSTRING*, CHARSET_INFO*)
- Changed some 'const char*' arrays to instead be of type LEX_CSTRING.
- class Item_func_units now used LEX_CSTRING for name.
Other things:
- Fixed a bug in mysql.cc:construct_prompt() where a wrong escape character
in the prompt would cause some part of the prompt to be duplicated.
- Fixed a lot of instances where the length of the argument to
append is known or easily obtain but was not used.
- Removed some not needed 'virtual' definition for functions that was
inherited from the parent. I added override to these.
- Fixed Ordered_key::print() to preallocate needed buffer. Old code could
case memory overruns.
- Simplified some loops when adding char * to a String with delimiters.
This was done to simplify copying of with_* flags
Other things:
- Changed Flags to C++ enums, which enables gdb to print
out bit values for the flags. This also enables compiler
errors if one tries to manipulate a non existing bit in
a variable.
- Added set_maybe_null() as a shortcut as setting the
MAYBE_NULL flags was used in a LOT of places.
- Renamed PARAM flag to SP_VAR to ensure it's not confused with persistent
statement parameters.
The reason for the change is that neither clang or gcc can do efficient
code when several bit fields are change at the same time or when copying
one or more bits between identical bit fields.
Updated bits explicitely with & and | is MUCH more efficient than what
current compilers can do.
- Defining MariaDB_FUNCTION_PLUGIN
- Changing the code in /plugins/type_inet/ and /plugins/type_test/
to use MariaDB_FUNCTION_PLUGIN instead of MariaDB_FUNCTION_COLLECTION_PLUGIN.
- Changing maturity for the INET6 data type plugin from experimental to alpha.
