The order of acquiring LOCK_mysql_create_db
and wait_if_global_read_lock() was wrong. It could happen
that a thread held LOCK_mysql_create_db while waiting for
the global read lock to be released. The thread with the
global read lock could try to administrate a database too.
It would first try to lock LOCK_mysql_create_db and hang...
The check if the current thread has the global read lock
is done in wait_if_global_read_lock(), which could not be
reached because of the hang in LOCK_mysql_create_db.
Now I exchanged the order of acquiring LOCK_mysql_create_db
and wait_if_global_read_lock(). This makes
wait_if_global_read_lock() fail with an error message for
the thread with the global read lock. No deadlock happens.
Replaced COND_refresh with COND_global_read_lock becasue of a bug in NTPL threads when using different mutexes as arguments to pthread_cond_wait()
The original code caused a hang in FLUSH TABLES WITH READ LOCK in some circumstances because pthread_cond_broadcast() was not delivered to other threads.
This fixes:
Bug#16986: Deadlock condition with MyISAM tables
Bug#20048: FLUSH TABLES WITH READ LOCK causes a deadlock
Added missing DBUG_xxx_RETURN statements
Fixed some usage of not initialized variables (as found by valgrind)
Ensure that we don't remove locked tables used as name locks from open table cache until unlock_table_names() are called.
This was fixed by having drop_locked_name() returning any table used as a name lock so that we can free it in unlock_table_names()
This will allow Tomas to continue with his work to use namelocks to syncronize things.
Note: valgrind still produces a lot of warnings about using not initialized code and shows memory loss errors when running the ndb tests
Use open_normal_and_derived_tables instead of open_and_lock_tables when reading metadata for a table.
Add two test cases, one for "USE database" and one for "SHOW COLUMNS FROM table"
Speed up column-completion in 'mysql'
Don't use ISAM if HAVE_ISAM is not defined
A lot of fixes for the embedded version. All libraries are now included in libmysqld.a
Changed arguments to convert_dirname() to make it more general.
Renamed files in the 'merge' directory to all use a common prefix.
Don't compile both assembler and C functions on x86
