in load_defaults()
load_defaults(), my_search_option_files() and
my_print_default_files() utilized a global variable
containing a pointer to thread local memory. This could lead
to race conditions when those functions were called with high
concurrency.
Fixed by changing the interface of the said functions to avoid
the necessity for using a global variable.
Since we cannot change load_defaults() prototype for API
compatibility reasons, it was renamed my_load_defaults().
Now load_defaults() is a thread-unsafe wrapper around
a thread-safe version, my_load_defaults().
The following type conversions was done:
- Changed byte to uchar
- Changed gptr to uchar*
- Change my_string to char *
- Change my_size_t to size_t
- Change size_s to size_t
Removed declaration of byte, gptr, my_string, my_size_t and size_s.
Following function parameter changes was done:
- All string functions in mysys/strings was changed to use size_t
instead of uint for string lengths.
- All read()/write() functions changed to use size_t (including vio).
- All protocoll functions changed to use size_t instead of uint
- Functions that used a pointer to a string length was changed to use size_t*
- Changed malloc(), free() and related functions from using gptr to use void *
as this requires fewer casts in the code and is more in line with how the
standard functions work.
- Added extra length argument to dirname_part() to return the length of the
created string.
- Changed (at least) following functions to take uchar* as argument:
- db_dump()
- my_net_write()
- net_write_command()
- net_store_data()
- DBUG_DUMP()
- decimal2bin() & bin2decimal()
- Changed my_compress() and my_uncompress() to use size_t. Changed one
argument to my_uncompress() from a pointer to a value as we only return
one value (makes function easier to use).
- Changed type of 'pack_data' argument to packfrm() to avoid casts.
- Changed in readfrm() and writefrom(), ha_discover and handler::discover()
the type for argument 'frmdata' to uchar** to avoid casts.
- Changed most Field functions to use uchar* instead of char* (reduced a lot of
casts).
- Changed field->val_xxx(xxx, new_ptr) to take const pointers.
Other changes:
- Removed a lot of not needed casts
- Added a few new cast required by other changes
- Added some cast to my_multi_malloc() arguments for safety (as string lengths
needs to be uint, not size_t).
- Fixed all calls to hash-get-key functions to use size_t*. (Needed to be done
explicitely as this conflict was often hided by casting the function to
hash_get_key).
- Changed some buffers to memory regions to uchar* to avoid casts.
- Changed some string lengths from uint to size_t.
- Changed field->ptr to be uchar* instead of char*. This allowed us to
get rid of a lot of casts.
- Some changes from true -> TRUE, false -> FALSE, unsigned char -> uchar
- Include zlib.h in some files as we needed declaration of crc32()
- Changed MY_FILE_ERROR to be (size_t) -1.
- Changed many variables to hold the result of my_read() / my_write() to be
size_t. This was needed to properly detect errors (which are
returned as (size_t) -1).
- Removed some very old VMS code
- Changed packfrm()/unpackfrm() to not be depending on uint size
(portability fix)
- Removed windows specific code to restore cursor position as this
causes slowdown on windows and we should not mix read() and pread()
calls anyway as this is not thread safe. Updated function comment to
reflect this. Changed function that depended on original behavior of
my_pwrite() to itself restore the cursor position (one such case).
- Added some missing checking of return value of malloc().
- Changed definition of MOD_PAD_CHAR_TO_FULL_LENGTH to avoid 'long' overflow.
- Changed type of table_def::m_size from my_size_t to ulong to reflect that
m_size is the number of elements in the array, not a string/memory
length.
- Moved THD::max_row_length() to table.cc (as it's not depending on THD).
Inlined max_row_length_blob() into this function.
- More function comments
- Fixed some compiler warnings when compiled without partitions.
- Removed setting of LEX_STRING() arguments in declaration (portability fix).
- Some trivial indentation/variable name changes.
- Some trivial code simplifications:
- Replaced some calls to alloc_root + memcpy to use
strmake_root()/strdup_root().
- Changed some calls from memdup() to strmake() (Safety fix)
- Simpler loops in client-simple.c
- BUG#22306: STOP INSTANCE can not be applied for instances in Crashed,
Failed and Abandoned;
- BUG#23476: DROP INSTANCE does not work
- BUG#23215: STOP INSTANCE takes too much time
BUG#22306:
The problem was that STOP INSTANCE checked that mysqld is up and running.
If it was not so, STOP INSTANCE reported an error. Now, STOP INSTANCE
reports an error if the instance has been started (mysqld can be down).
BUG#23476:
The problem was that DROP INSTANCE tried to stop inactive instance. The fix is
trivial.
BUG#23215:
The problem was that locks were not acquired properly, so the
instance-monitoring thread could not acquire the mutex, holded by the
query-processing thread.
The fix is to simplify locking scheme by moving instance-related information to
Instance-class out of Guardian-class. This allows to get rid of storing a
separate list of Instance-information in Guardian and keeping it synchronized
with the original list in Instance_map.
- change some return types from int to bool;
- add [ERROR] tag to log_error() output;
- add [INFO] tag to log_info() output;
- change log messages to be more consistent.
Alik's patch for BUG#22306: STOP INSTANCE can not be applied for
instances in Crashed, Failed and Abandoned" to ease review process.
Evaluate global variable linuxthreads before starting threads to avoid
a race.
The problem was that IM stoped guarded instances on shutdown,
but didn't wait for them to stop.
The fix is to wait for guarded instances to stop before exitting
from the main thread.
The idea is that Instance-monitoring thread should add itself
to Thread_registry so that it will be taken into account on shutdown.
However, Thread_registry should not signal it on shutdown in order to
not interrupt wait()/waitpid().
- WL#3158: IM: Instance configuration extensions;
- WL#3159: IM: --bootstrap and --start-default-instance modes
The following new statements have been added:
- CREATE INSTANCE;
- DROP INSTANCE;
The behaviour of the following statements have been changed:
- SET;
- UNSET;
- FLUSH INSTANCES;
- SHOW INSTANCES;
- SHOW INSTANCE OPTIONS;
duration of the whole 'flush instances'. As a consequence,
it was possible to query instance map, while it is in the
inconsistent state. The patch was reworked after review.
