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.
MyISAM only allows online alter if autoincrement didn't change.
MyISAM detects that by comparing new autoinc value from create_info,
with the old one, stored in MYI. But in partitioned tables,
create_info->auto_increment_value is for the whole table, max of
autoinc values of individual MYI partitions. So *some* MYI partitions
will inevitably think that alter table changes auto_increment value
and will deny online alter.
Fix: only compare autoinc values, if the user has used AUTO_INCREMENT
in the ALTER TABLE statement.
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().
This excludes MDEV-12472 (InnoDB should accept XtraDB parameters,
warning that they are ignored). In other words, MariaDB 10.3 will not
recognize any XtraDB-specific parameters.
Don't rebuild the table for ALTER TABLE delay_key_write changes.
After that, delay_key_write value in .frm may differ from the
value in .MYI. We'll do what .frm says.
Do not silence uncertain cases, or fix any bugs.
The only functional change should be that ha_federated::extra()
is not calling DBUG_PRINT to report an unhandled case for
HA_EXTRA_PREPARE_FOR_DROP.
Do not silence uncertain cases, or fix any bugs.
The only functional change should be that ha_federated::extra()
is not calling DBUG_PRINT to report an unhandled case for
HA_EXTRA_PREPARE_FOR_DROP.
This affected mainly MyISAM and Aria engines.
Also fixed that end_bulk_insert() detects errors from
internal mi_end_bulk_insert() and ma_end_bulk_insert()
- delete_tree() and delete_tree_element() now has an
extra argument that marks if future calls to
tree->free should be ignored.
- tree->free changed to function returning int, to be
able to signal errors.
- Restored deleting flag in MyISAM that was accidently
disabled in mi_extra(PREPARE_FOR_DROP)
The issue was that my_errno was not set properly when a repair was killed,
which confused the rpl_killed_ddl script.
I also added an extra test line in varchar.inc to ensure we don't give
duplicate error rows.
bunch of bugs when external_lock() fails on unlock:
* mi_lock_database() used mi_mark_crashed() under share->intern_lock,
but mi_mark_crashed() itself locks this mutex.
* handler::close() required table to be unlocked, but failed
external_lock didn't count as unlock
* mysql_unlock_tables() ignored all unlock errors, but they still set
the error status in stmt_da.
SYMLINK CHECK RACE CONDITIONS
ANALYSIS:
=========
A potential defect exists in the handling of CREATE
TABLE .. DATA DIRECTORY/ INDEX DIRECTORY which gives way to
the user to gain access to another user table or a system
table.
FIX:
====
The lstat and fstat output of the target files are now
stored which help in determining the identity of the target
files thus preventing the unauthorized access to other
files.
Other things
- Ensure that ut_d() is set to EXPR if ut_ad() is DEBUG_ASSERT()
If not, we will get a crash in purge_sys_t::~purge_sys_t() as
this ut_ad() code expect's that the ut_d() codes has been executed
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.
Working features:
CREATE OR REPLACE [TEMPORARY] SEQUENCE [IF NOT EXISTS] name
[ INCREMENT [ BY | = ] increment ]
[ MINVALUE [=] minvalue | NO MINVALUE ]
[ MAXVALUE [=] maxvalue | NO MAXVALUE ]
[ START [ WITH | = ] start ] [ CACHE [=] cache ] [ [ NO ] CYCLE ]
ENGINE=xxx COMMENT=".."
SELECT NEXT VALUE FOR sequence_name;
SELECT NEXTVAL(sequence_name);
SELECT PREVIOUS VALUE FOR sequence_name;
SELECT LASTVAL(sequence_name);
SHOW CREATE SEQUENCE sequence_name;
SHOW CREATE TABLE sequence_name;
CREATE TABLE sequence-structure ... SEQUENCE=1
ALTER TABLE sequence RENAME TO sequence2;
RENAME TABLE sequence TO sequence2;
DROP [TEMPORARY] SEQUENCE [IF EXISTS] sequence_names
Missing features
- SETVAL(value,sequence_name), to be used with replication.
- Check replication, including checking that sequence tables are marked
not transactional.
- Check that a commit happens for NEXT VALUE that changes table data (may
already work)
- ALTER SEQUENCE. ANSI SQL version of setval.
- Share identical sequence entries to not add things twice to table list.
- testing insert/delete/update/truncate/load data
- Run and fix Alibaba sequence tests (part of mysql-test/suite/sql_sequence)
- Write documentation for NEXT VALUE / PREVIOUS_VALUE
- NEXTVAL in DEFAULT
- Ensure that NEXTVAL in DEFAULT uses database from base table
- Two NEXTVAL for same row should give same answer.
- Oracle syntax sequence_table.nextval, without any FOR or FROM.
- Sequence tables are treated as 'not read constant tables' by SELECT; Would
be better if we would have a separate list for sequence tables so that
select doesn't know about them, except if refereed to with FROM.
Other things done:
- Improved output for safemalloc backtrack
- frm_type_enum changed to Table_type
- Removed lex->is_view and replaced with lex->table_type. This allows
use to more easy check if item is view, sequence or table.
- Added table flag HA_CAN_TABLES_WITHOUT_ROLLBACK, needed for handlers
that want's to support sequences
- Added handler calls:
- engine_name(), to simplify getting engine name for partition and sequences
- update_first_row(), to be able to do efficient sequence implementations.
- Made binlog_log_row() global to be able to call it from ha_sequence.cc
- Added handler variable: row_already_logged, to be able to flag that the
changed row is already logging to replication log.
- Added CF_DB_CHANGE and CF_SCHEMA_CHANGE flags to simplify
deny_updates_if_read_only_option()
- Added sp_add_cfetch() to avoid new conflicts in sql_yacc.yy
- Moved code for add_table_options() out from sql_show.cc::show_create_table()
- Added String::append_longlong() and used it in sql_show.cc to simplify code.
- Added extra option to dd_frm_type() and ha_table_exists to indicate if
the table is a sequence. Needed by DROP SQUENCE to not drop a table.
MyISAM in compute_vcols() - which is used only in mi_check code -
was computing indexed vcols into an internally allocated buffer
(not record[0]) and the buffer was calculated to be long enough to fit
every keyseg (a keyseg knows where its value in a record buffer is
and the length of the value).
This logic didn' work for prefix keys, because the keyseg length is the
length of a prefix, but the record buffer needs to fit the complete
value of a vcol. In this bug MyISAM was writing a 2K varchar
into a buffer too short.
Also it didn't work for repair-with-keycache, because that code
recalculats all vcols, not only indexed ones.
So, the buffer size (MYISAM_SHARE::vreclength) should include all
vcols' full lengths. But it was calculated in mi_open and low-level
MyISAM code has no knowledge of vcols.
As a fix we now recalculate MYISAM_SHARE::vreclength in
ha_myisam::setup_vcols_for_repair() which is always called
before compute_vcols().
FT_BOOLEAN_CHECK_SYNTAX_STRING
ISSUE: my_isalnum macro used for checking if character is
alphanumeric dereferences uninitialized pointer
in default character set structure resulting in
server exiting abnormally.
FIX: Used standard isalnum function instead of macro my_isalnum.
Also, implement MDEV-11027 a little differently from 5.5 and 10.0:
recv_apply_hashed_log_recs(): Change the return type back to void
(DB_SUCCESS was always returned).
Report progress also via systemd using sd_notifyf().
Also, implement MDEV-11027 a little differently from 5.5:
recv_sys_t::report(ib_time_t): Determine whether progress should
be reported.
recv_apply_hashed_log_recs(): Rename the parameter to last_batch.
Define my_thread_id as an unsigned type, to avoid mismatch with
ulonglong. Change some parameters to this type.
Use size_t in a few more places.
Declare many flag constants as unsigned to avoid sign mismatch
when shifting bits or applying the unary ~ operator.
When applying the unary ~ operator to enum constants, explictly
cast the result to an unsigned type, because enum constants can
be treated as signed.
In InnoDB, change the source code line number parameters from
ulint to unsigned type. Also, make some InnoDB functions return
a narrower type (unsigned or uint32_t instead of ulint;
bool instead of ibool).
my_readline can fail due to missing file. Make my_readline report this
condition separately so that we can catch it and report an appropriate
error message to the user.
it was race condition prone. instead use either a pair of my_delete()
calls with already resolved paths, or a safe high-level function
my_handler_delete_with_symlink(), like MyISAM and Aria already do.
