This commit fixes the following issues:
- memory leak checking enabled for mysqltest. This cover all cases except
calls to 'die()' that only happens in case of internal failures in
mysqltest. die() is not called anymore in the result files differs.
- One can now run mtr --embedded without failures (this crashed or hang
before)
- cleanup_and_exit() has a new parameter that indicates that it is called
from die(), in which case we should not do memory leak checks. We now
always call cleanup_and_exit() instead of exit() to be able to free up
memory and discover memory leaks.
- Lots of new assert to catch error conditions
- More DBUG statements.
- Fixed that all results are freed in mysqltest (Fixed a memory leak in
mysqltest when using prepared statements).
- Fixed race condition in do_stmt_close() that caused embedded server
to not free memory. (Memory leak in mysqltest with embedded server).
- Fixed two memory leaks in embedded server when using prepared statements.
These memory leaks caused timeout hangs in mtr when server was compiled
with safemalloc. This issue was not noticed (except as timeouts) as
memory report checking was done but output of it was disabled.
In some cases "SHOW PROCESSLIST" could show "Reset for next command"
as State, even if the previous query had finished properly.
Fixed by clearing State after end of command and also setting the State
for the "Connect" command.
Other things:
- Changed usage of 'thd->set_command(COM_SLEEP)' to
'thd->mark_connection_idle()'.
- Changed thread_state_info() to return "" instead of NULL. This is
just a safety measurement and in line with the logic of the
rest of the function.
This happens when compiled with HAVE_EMBEDDED_PRIVILEGE_CONTROL.
There is a lot of other problems with the above option that should
be fixed at some point
* provide an argument to the callback
* don't ignore a callback request if it's already present in the queue
* initialize mutex/cond/in_use flag before starting the thread,
in case the first callback queueing request arrives before
handle_manager had time to initialize
* set/check abort_manager under a mutex, otherwise handle_manager
thread might destroy LOCK_manager before stop_handle_manager
released it
* signal COND on queueing a callback, stop cond_wait on callback request
* always start the thread, even if flush_time is 0
* but keep the old behavior in embedded (no replication, no galera)
* style cleanups (e.g. remove volatile for a variable protected by a mutex)
Protocol_local fixed so it can be used now.
Some Protocol:: methods made virtual so they can adapt.
as well as net_ok and net_send_error functions.
execute_sql_string function is exported to the plugins.
To be changed with the mysql_use_result.
The problem happened because Item_ident_for_show did not implement val_native().
Solution:
- Removing class Item_ident_for_show
- Implementing a new method Protocol::send_list_fields() instead,
which accepts a List<Field> instead of List<Item> as input.
Now no any Item creation is done during mysqld_list_fields().
Adding helper methods, to reuse the code easier:
- Moved a part of Protocol::send_result_set_metadata(),
responsible for sending an individual field metadata,
into a new method Protocol_text::store_field_metadata().
Reusing it in both send_list_fields() and send_result_set_metadata().
- Adding Protocol_text::store_field_metadata()
- Adding Protocol_text::store_field_metadata_for_list_fields()
Note, this patch also automatically fixed another bug:
MDEV-18685 mysql_list_fields() returns DEFAULT 0 instead of DEFAULT NULL for view columns
The reason for this bug was that Item_ident_for_show::val_xxx() and get_date()
did not check field->is_null() before calling field->val_xxx()/get_date().
Now the default value is correctly sent by Protocol_text::store(Field*).
Implemented and integrated THD_list as a replacement for the global
thread list. It uses own mutex instead of LOCK_thread_count for THD
list protection.
Removed unused first_global_thread() and next_global_thread().
delayed_insert_threads is now protected by LOCK_delayed_insert. Although
this patch doesn't fix very wrong synchronization of this variable.
After this patch there are only 2 legitimate uses of LOCK_thread_count
left, both in mysqld.cc: thread_count and ready_to_exit.
Aim is to reduce usage of LOCK_thread_count and COND_thread_count.
Part of MDEV-15135.
Returned accidentally removed undefinition of MYSQL_SERVER in net_serv.cc inside embedded server
(embedded server uses real_net_read/write only as a client)
Prevented attempt to clean up embedded server if it was not initialized
Renaming methods:
- Field::make_field(Send_field*) to make_send_field(..)
- Item::make_field(THD *,Send_field *) to make_send_field(..)
- Item::init_make_field(Send_field *, enum_field_type) to init_make_send_field(..)
These names looked similar to other functions that are used
for a very different purpose (creating Field instances):
- Public function "Field * make_field(..)"
- Method "Field *Column_defitinion::make_field(..)"
The rename makes it's easier to search the code using "grep".
This will make it easier to how memory allocation is done when debugging
with either DBUG or gdb.
Will especially help when debugging stored procedures
Main change is a name argument as second argument to init_alloc_root()
init_sql_alloc()
Other things:
- Added DBUG_ENTER/EXIT to some Virtual_tmp_table functions
This was done in, among other things:
- thd->db and thd->db_length
- TABLE_LIST tablename, db, alias and schema_name
- Audit plugin database name
- lex->db
- All db and table names in Alter_table_ctx
- st_select_lex db
Other things:
- Changed a lot of functions to take const LEX_CSTRING* as argument
for db, table_name and alias. See init_one_table() as an example.
- Changed some function arguments from LEX_CSTRING to const LEX_CSTRING
- Changed some lists from LEX_STRING to LEX_CSTRING
- threads_mysql.result changed because process list_db wasn't always
correctly updated
- New append_identifier() function that takes LEX_CSTRING* as arguments
- Added new element tmp_buff to Alter_table_ctx to separate temp name
handling from temporary space
- Ensure we store the length after my_casedn_str() of table/db names
- Removed not used version of rename_table_in_stat_tables()
- Changed Natural_join_column::table_name and db_name() to never return
NULL (used for print)
- thd->get_db() now returns db as a printable string (thd->db.str or "")
