------------------------------------------------------------
revno: 2630.4.39
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Thu 2008-06-26 13:08:27 +0400
message:
  Fix warnings about passing pointer to not fully-initialized THD
  object to constructor of base Open_tables_state classe, which
  appeared on Windows and were introduced by one of the patches
  implementing WL#3726 "DDL locking for all metadata objects".

sql/sql_class.cc:
  Moved code preparing Open_tables_state instance for operations
  which open/lock/close tables from class constructor to
  init_open_tables_state() method. This allows us to move such
  initialization of base Open_table_state instance in THD class
  constructor from base classes initialization section to
  constructor's body and thus to get rid of warnings about
  about passing pointer to not fully-initialized THD object
  to base class constructor.
sql/sql_class.h:
  Moved code preparing Open_tables_state instance for operations
  which open/lock/close tables from class constructor to
  init_open_tables_state() method. This allows us to move such
  initialization of base Open_table_state instance in THD class
  constructor from base classes initialization section to
  constructor's body and thus to get rid of warnings about
  about passing pointer to not fully-initialized THD object
  to base class constructor.

----------------------------------------------------------
revno: 2630.4.38
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-4144
timestamp: Wed 2008-06-25 22:07:06 +0400
message:
  WL#4144 - Lock MERGE engine children.
  Committing a version of the patch merged with WL#3726
  on behalf of Ingo.

  Step #1: Move locking from parent to children.

  MERGE children are now left in the query list of tables
  after inserted there in open_tables(). So they are locked
  by lock_tables() as all other tables are.

  The MERGE parent does not store locks any more. It appears
  in a MYSQL_LOCK with zero lock data. This is kind of a "dummy"
  lock.

  All other lock handling is also done directly on the children.
  To protect against parent or child modifications during LOCK
  TABLES, the children are detached after every statement and
  attached before every statement, even under LOCK TABLES.

  The children table list is removed from the query list of tables
  on every detach and on close of the parent.

  Step #2: Move MERGE specific functionality from SQL layer
  into table handler.

  Functionality moved from SQL layer (mainly sql_base.cc)
  to the table handler (ha_myisammrg.cc).

  Unnecessary code is removed from the SQL layer.

  Step #3: Moved all MERGE specific members from TABLE
  to ha_myisammrg.

  Moved members from TABLE to ha_myisammrg.
  Renamed some mebers.
  Fixed comments.

  Step #4: Valgrind and coverage testing

  Valgrind did not uncover new problems.
  Added purecov comments.

  Added a new test for DATA/INDEX DIRECTORY options.
  Changed handling of ::reset() for non-attached children.
  Fixed the merge-big test.

  Step #5: Fixed crashes detected during review
  Changed detection when to attach/detach.
  Added new tests.

Backport also the fix for Bug#44040 "MySQL allows creating a 
MERGE table upon VIEWs but crashes when using it"


include/my_base.h:
  WL#4144 - Lock MERGE engine children
  Added HA_EXTRA_ADD_CHILDREN_LIST and HA_EXTRA_IS_ATTACHED_CHILDREN
  for MERGE table support
mysql-test/r/merge.result:
  WL#4144 - Lock MERGE engine children
  Fixed test result.
mysql-test/t/disabled.def:
  Enable merge.test, which now is working again (WL#4144).
mysql-test/t/merge-big.test:
  Fix the messages for wait_condition (merge with WL#3726).
mysql-test/t/merge.test:
  WL#4144 - Lock MERGE engine children
  Fixed one test to meet coding standards for tests
  (upper case keywords, engine names as in SHOW ENGINES).
  Fixed error codes.
  Added a test for DATA/INDEX DIRECTORY.
mysys/thr_lock.c:
  WL#4144 - Lock MERGE engine children
  Added purecov comments.
sql/ha_partition.cc:
  WL#4144 - Lock MERGE engine children
  Added MERGE specific extra operations to ha_partition::extra().
  Extended comments.
  Changed function comment to doxygen style.
  Fixed nomenclature: 'parameter' -> 'operation'.
sql/mysql_priv.h:
  WL#4144 - Lock MERGE engine children
  Removed declarations for removed functions.
sql/sql_base.cc:
  WL#4144 - Lock MERGE engine children
  Leave the children in the query list of tables after open_tables().
  Set proper back links (prev_global).
  Attach MERGE children before and detach them after every
  statement. Even under LOCK TABLES.
  Remove children from the query list when they are detached.
  Remove lock forwarding from children to parent.
  Moved MERGE specific functions to ha_myisammrg.cc.
  Added purecov comments.
  Backport the fix for Bug#44040 "MySQL allows creating a MERGE table upon VIEWs but crashes when using it"
sql/sql_table.cc:
  WL#4144 - Lock MERGE engine children
  Changed detection of MERGE tables.
sql/table.cc:
  WL#4144 - Lock MERGE engine children
  Moved is_children_attached() method from TABLE to ha_myisammrg.
sql/table.h:
  WL#4144 - Lock MERGE engine children
  Moved all MERGE specific members from TABLE to ha_myisammrg.
storage/myisammrg/ha_myisammrg.cc:
  WL#4144 - Lock MERGE engine children
  Set proper back links in the child list (prev_global).
  Added a function for removal of the child list from the query list.
  Remove children from the query list when the parent is closed.
  Make parent lock handling a dummy (zero locks).
  Moved MERGE specific functionality from SQL layer to here.
  Moved all MERGE specific members from TABLE to ha_myisammrg.
  Renamed children list pointers.
  Added initialization and free for the children list mem_root.
  Fixed comments.
  Added purecov comments.
storage/myisammrg/ha_myisammrg.h:
  WL#4144 - Lock MERGE engine children
  Added method add_children_list().
  Moved all MERGE specific members from TABLE to ha_myisammrg.
  Renamed children list pointers.
  Added a mem_root for the children list.
storage/myisammrg/myrg_extra.c:
  WL#4144 - Lock MERGE engine children
  Changed handling of ::reset() for non-attached children.

------------------------------------------------------------
revno: 2630.4.37
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Wed 2008-06-25 20:28:57 +0400
message:
  Fix build failure of mysql-6.0-3726 tree on Windows.

  The failure was caused by the fact that sql/mdl.cc was
  using __func__ macro without including sql_profile.h
  header which contained definition of this macro for
  those platforms that miss it.

  This patch solves this problem by moving this define to
  include/my_global.h which makes it available in modules
  which don't/can't include sql/mysql_priv.h.

This is a patch that is part of WL#3726.

include/my_global.h:
  Moved definition of __func__ macro from sql/sql_profile.h to
  include/my_global.h to make it accessible from those modules
  of the server which don't include mysql_priv.h.
sql/sql_profile.cc:
  Removed _unknown_func_ const variable since it is no longer used
  by __func__ macro.
sql/sql_profile.h:
  Moved definition of __func__ macro from sql/sql_profile.h to
  include/my_global.h to make it accessible from those modules
  of the server which don't include mysql_priv.h.

----------------------------------------------------------
revno: 2630.4.36
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-3726
timestamp: Wed 2008-06-25 17:03:37 +0400
message:
  As per discussion with Serg and Dmitri, remove the code
  that is trying to emulate LOCK TABLES when locking tables for prelocking.
  This code was worked around by the engines, and has no effect.
  We may still have to do something to ensure that statement-based
  replication is consistent in MVCC engines, or other engines
  that downgrade table level locks, but this will have to be done
  somehow differently.


sql/sql_base.cc:
  Do not try to emulate LOCK TABLES when locking tables for
  pre-locking.

----------------------------------------------------------
revno: 2630.4.35
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-3726
timestamp: Wed 2008-06-25 16:44:00 +0400
message:
  Fix a MyISAM-specific bug in the new implementation of
  LOCK TABLES (WL#3726).
  If more than one instance of a MyISAM table are open in the
  same connection, all of them must share the same status_param.
  Otherwise, unlock of a table may lead to lost records.
  See also comments in thr_lock.c.

include/thr_lock.h:
   Declare thr_lock_merge_status().
mysql-test/r/lock.result:
  Update test results (WL#3726).
mysql-test/t/lock.test:
  Add a test case for the situation when the same table is locked
  twice by LOCK TABLES, and only one instance is updated.
mysys/thr_lock.c:
  Move the code that makes sure all status_params of the same
  table are shared into a separate function.
sql/lock.cc:
  Make sure that status_param is shared when a table is reopened.

------------------------------------------------------------
revno: 2630.4.33
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Fri 2008-06-20 17:11:20 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After-review fixes in progress.

  Minimized dependency of mdl.cc on other modules (particularly
  made it independant of mysql_priv.h) in order to be able
  write unit tests for metadata locking subsystem.


sql/ha_ndbcluster_binlog.cc:
  Use newly introduced MAX_MDLKEY_LENGTH constant for allocating
  buffer for object key for metadata locking subsystem.
sql/log_event.cc:
  Use newly introduced MAX_MDLKEY_LENGTH constant for allocating
  buffer for object key for metadata locking subsystem.
sql/mdl.cc:
  Removed dependency on THD class (and thus on mysql_priv.h)
  by using direct access to members of st_my_thread_var instead
  of accessing THD::killed/enter_cond()/exit_cond().
sql/mdl.h:
  Added MAX_MDLKEY_LENGTH constant to be used for allocating
  buffers for key for metadata locking subsystem.
  Added declarations of server kernel functions used by metadata
  locking subsystem to mdl.h in order to decrease dependency of
  mdl.cc on other files.
sql/mysql_priv.h:
  Moved declaration of notify_thread_having_shared_lock() to the
  mdl.h (also renamed it to make clear in metadata locking code
  that it is a callback to SQL-layer).
sql/sql_base.cc:
  Renamed notify_thread_having_shared_lock() to make it clear
  in metadata locking subsystem code that it is a callback
  to SQL layer.
sql/sql_handler.cc:
  Use newly introduced MAX_MDLKEY_LENGTH constant for allocating
  buffer for object key for metadata locking subsystem.
sql/sql_show.cc:
  Use newly introduced MAX_MDLKEY_LENGTH constant for allocating
  buffer for object key for metadata locking subsystem.

------------------------------------------------------------
revno: 2630.4.32
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Thu 2008-06-19 16:39:58 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After-review fixes in progress.

  Ensure that metadata locking subsystem properly handles
  out-of-memory conditions. Clarified MDL interface by
  separating release of locks and removal of lock requests
  from the context.

sql/lock.cc:
  mdl_release_lock(), mdl_acquire_exclusive_locks() and 
  mdl_try_acquire_exclusive_lock() are no longer responsible
  for removal of metadata lock requests from the context.
  One should explicitly call mdl_remove_all_locks() and
  mdl_remove_lock() to do this.
sql/mdl.cc:
  Ensured that metadata locking subsystem properly handles
  out-of-memory conditions.
  Introduced new MDL_INITIALIZED state for metadata lock
  request which is used in all cases when lock is not acquired 
  and we have not associated request with object respesenting 
  lock.
  
  MDL_PENDING is now only used for requests for exclusive locks
  which are added to the MDL_LOCK::waiting_exclusive queue.
  mdl_release_lock(), mdl_acquire_exclusive_locks() and 
  mdl_try_acquire_exclusive_lock() are no longer responsible
  for removal of metadata lock requests from the context.
  One should explicitly call mdl_remove_all_locks() and
  newly introduced mdl_remove_lock() to do this.
  Also renamed mdl_release_all_locks_for_name() to 
  emphasize that it also actually removes lock requests
  from the context.
  
  Finally mdl_try_acquire_exclusive_lock() is now returs
  information about encountered lock conflict in separate
  out parameter since its return value is used for distinguishing
  between error (e.g. due to OOM) and success.
sql/mdl.h:
  Introduced new MDL_INITIALIZED state for metadata lock
  request which is used in all cases when lock is not acquired 
  and we have not associated request with object respesenting 
  lock.
  
  MDL_PENDING is now only used for requests for exclusive locks
  which are added to the MDL_LOCK::waiting_exclusive queue.
  mdl_release_lock(), mdl_acquire_exclusive_locks() and 
  mdl_try_acquire_exclusive_lock() are no longer responsible
  for removal of metadata lock requests from the context.
  One should explicitly call mdl_remove_all_locks() and
  newly introduced mdl_remove_lock() to do this.
  Also renamed mdl_release_all_locks_for_name() to 
  emphasize that it also actually removes lock requests
  from the context.
  
  Finally mdl_try_acquire_exclusive_lock() is now returs
  information about encountered lock conflict in separate
  out parameter since its return value is used for distinguishing
  between error (e.g. due to OOM) and success.
sql/sql_base.cc:
  mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible
  for removal of metadata lock requests from the context.
  One should explicitly call mdl_remove_all_locks() and
  mdl_remove_lock() to do this.
  Also adjusted open_table() to ensure that it 
  releases/removes metadata locks in case of error 
  after adding/acquiring them (unless keeping these
  lock requests is required for recovering action).
sql/sql_delete.cc:
  mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible
  for removal of metadata lock requests from the context.
  One should explicitly call mdl_remove_all_locks() and
  mdl_remove_lock() to do this.
sql/sql_handler.cc:
  mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible
  for removal of metadata lock requests from the context.
  One should explicitly call mdl_remove_all_locks() and
  mdl_remove_lock() to do this.
sql/sql_show.cc:
  mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible
  for removal of metadata lock requests from the context.
  One should explicitly call mdl_remove_all_locks() and
  mdl_remove_lock() to do this.
sql/sql_table.cc:
  Renamed mdl_release_all_locks_for_name() to emphasize
  that it also actually removes lock requests from the context.
  mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible
  for removal of metadata lock requests from the context.
  One should explicitly call mdl_remove_all_locks() and
  mdl_remove_lock() to do this.
  Finally mdl_try_acquire_exclusive_lock() is now returs
  information about encountered lock conflict in separate
  out parameter since its return value is used for distinguishing
  between error (e.g. due to OOM) and success.

----------------------------------------------------------
revno: 2630.4.31
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-3726
timestamp: Thu 2008-06-12 06:23:08 +0400
message:
  Extend the signature of TABLE_LIST::init_one_table() to 
  initialize lengths

This is part of WL#3726 post-review fixes.

----------------------------------------------------------
revno: 2630.4.30
Konstantin Osipov   2008-06-11
Fix a potential cause of test failures.

sql/sql_base.cc:
  0 may not be equal to (char*) 0 on 64 bit pointer/32 bit int machines.

----------------------------------------------------------
revno: 2630.10.1
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-lock-tables-tidyup
timestamp: Wed 2008-06-11 15:49:58 +0400
message:
  WL#3726, review fixes.
  Now that we have metadata locks, we don't need to keep a crippled
  TABLE instance in the table cache to indicate that a table is locked.
  Remove all code that used this technique. Instead, rely on metadata
  locks and use the standard open_table() and close_thread_table()
  to manipulate with the table cache tables.
  Removes a list of functions that have become unused (see the comment
  for sql_base.cc for details).
  Under LOCK TABLES, keep a TABLE_LIST instance for each table
  that may be temporarily closed. For that, implement an own class for
  LOCK TABLES mode, Locked_tables_list.

This is a pre-requisite patch for WL#4144.
This is not exactly a backport: there is no new 
online ALTER table in Celosia, so the old alter table
code was changed to work with the new table cache API.


mysql-test/r/lock.result:
  Update results (WL#3726 post-review patch).
mysql-test/r/trigger-compat.result:
  We take the table from the table cache now, thus no warning.
mysql-test/suite/rpl/r/rpl_trigger.result:
  We take the table from the table cache now, thus no warning.
mysql-test/t/lock.test:
  Additional tests for LOCK TABLES mode (previously not covered by
  the test suite (WL#3726).
sql/field.h:
  Remove reopen_table().
sql/lock.cc:
  Remove an obsolete parameter of mysql_lock_remove().
  It's not used anywhere now either.
sql/mysql_priv.h:
  Add 4 new open_table() flags.
  Remove declarations of removed functions.
sql/sp_head.cc:
  Rename thd->mdl_el_root to thd->locked_tables_root.
sql/sql_acl.cc:
  Use the new implementation of unlock_locked_tables().
sql/sql_base.cc:
  Implement class Locked_tables_list.
  Implement close_all_tables_for_name().
  Rewrite close_cached_tables() to use the new reopen_tables().
  Remove reopen_table(), reopen_tables(), reopen_table_entry() 
  (ex. open_unireg_entry()), close_data_files_and_leave_as_placeholders(),
  close_handle_and_leave_table_as_placeholder(), close_cached_table(),
  table_def_change_share(), reattach_merge(), reopen_name_locked_table(),
  unlink_open_table().
  
  Move acquisition of a metadata lock into an own function
  - open_table_get_mdl_lock().
sql/sql_class.cc:
  Deploy class Locked_tables_list.
sql/sql_class.h:
  Declare class Locked_tables_list.
  Keep one instance of this class in class THD.
  Rename mdl_el_root to locked_tables_root.
sql/sql_db.cc:
  Update a comment.
sql/sql_insert.cc:
  Use the plain open_table() to open a just created table in
  CREATE TABLE .. SELECT.
sql/sql_parse.cc:
  Use thd->locked_tables_list to enter and leave LTM_LOCK_TABLES mode.
sql/sql_partition.cc:
  Deploy the new method of working with partitioned table locks.
sql/sql_servers.cc:
  Update to the new signature of unlock_locked_tables().
sql/sql_table.cc:
  In mysql_rm_table_part2(), the branch that removes a table under
  LOCK TABLES, make sure that the table being dropped
  is also removed from THD::locked_tables_list.
  Update ALTER TABLE and CREATE TABLE LIKE implementation to use
  open_table() and close_all_tables_for_name() instead of 
  reopen_tables().
sql/sql_trigger.cc:
  Use the new locking way.
sql/table.h:
  Add TABLE::pos_in_locked_tables, which is used only under
  LOCK TABLES.

```---------------------------------------------------------
revno: 2630.9.3
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w3
timestamp: Wed 2008-06-11 08:33:36 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.

  Changed close_cached_tables() not to flush all unused TABLE
  instances when flushing individual table.
  Renamed expel_table_from_cache() to tdc_remove_table() and
  added enum parameter to be able more explicitly specify type
  of removal, rewrote its code to be more efficient.

******
Backport of:
```

---------------------------------------------------------
revno: 2630.9.4
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w3
timestamp: Wed 2008-06-11 15:53:53 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After-review fixes in progress.

  Minor changes in order to improve code readability
  and simplify debugging.


mysql-test/r/ps_ddl.result:
  Restore the original (correct) behaviour,
  now that the patch that fixes the regression
  introduced by the original patch for WL#3726 is fixed.
mysql-test/t/ps_ddl.test:
  Restore the original (correct) behaviour,
  now that the patch that fixes the regression
  introduced by the original patch for WL#3726 is fixed
sql/mysql_priv.h:
  Renamed expel_table_from_cache() to tdc_remove_table() 
  and added enum parameter to be able more explicitly specify 
  type of removal.
sql/sql_base.cc:
  Changed close_cached_tables() not to flush all unused TABLE
  instances when flushing individual table.
  Renamed expel_table_from_cache() to tdc_remove_table() and added
  enum parameter to be able more explicitly specify type of
  removal, rewrote its code to be more efficient. As result removed
  relink_unused() function which is no longer used.
  ******
  Improved code in close_cached_tables() according to reviewer's
  comments.
sql/sql_delete.cc:
  Renamed expel_table_from_cache() to tdc_remove_table() 
  and added enum parameter to be able more explicitly 
  specify type of removal.
sql/sql_rename.cc:
  Renamed expel_table_from_cache() to tdc_remove_table() 
  and added enum parameter to be able more explicitly 
  specify type of removal.
sql/sql_show.cc:
  Moved acquisition of high-prio shared metadata lock in which
  happens in fill_schema_table_from_frm() to separate function.
sql/sql_table.cc:
  Renamed expel_table_from_cache() to tdc_remove_table() 
  and added enum parameter to be able more explicitly 
  specify type of removal.
sql/sql_trigger.cc:
  Renamed expel_table_from_cache() to tdc_remove_table() 
  and added enum parameter to be able more explicitly 
  specify type of removal.

------------------------------------------------------------
revno: 2630.9.2
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w3
timestamp: Tue 2008-06-10 18:01:56 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.


sql/mdl.cc:
  Changed mdl_acquire_shared_lock() signature to accept MDL_CONTEXT
  as one of arguments as described in specification.
sql/mdl.h:
  Changed mdl_acquire_shared_lock() signature to accept MDL_CONTEXT
   as one of arguments as described in specification.
sql/sql_base.cc:
  Changed mdl_acquire_shared_lock() signature to accept MDL_CONTEXT
  as one of arguments as described in specification.
  Renamed handle_failed_open_table_attempt() to
  recover_from_failed_open_table_attempt() as suggested by review.
  Added comment clarifying why we need to check TABLE::db_stat
  while looking at TABLE instances open by other threads.
sql/sql_show.cc:
  Changed mdl_acquire_shared_lock() signature to accept MDL_CONTEXT
  as one of arguments as described in specification.

------------------------------------------------------------ 
revno: 2630.9.1 
committer: Dmitry Lenev <dlenev@mysql.com> 
branch nick: mysql-6.0-3726-w3 
timestamp: Sun 2008-06-08 22:13:58 +0400 
message: 
  WL#3726 "DDL locking for all metadata objects" 
   
  After review fixes in progress. 
   
  Some adjustments to the patch that removes thd->locked_tables

sql/sp_head.cc:
  Fix conditions which were wrongly translated by previous patch.
sql/sql_base.cc:
  close_thread_tables():
    Add comment clarifying control flow in case of LTM_LOCK_TABLES
    mode and statements requiring prelocking.
    Be consistent with other places where we clear
    OPTION_TABLE_LOCK flag.
  lock_tables():
    Always set THD::lock to 0 after freeing memory to which it
    points.

------------------------------------------------------------
revno: 2630.4.27
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Mon 2008-06-09 14:01:19 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.

  Changed open_table() to return bool. This allows more easily to
  distinguish cases when this function succeeds but returns no TABLE
  instance (in case of view or in case of special kind of open) from
  cases when we have an error. Pointer to TABLE instance is now
  always returned in TABLE_LIST::table member.

  This change allows to get rid of false assumption in open_tables()
  implementation and makes it more clear.

----------------------------------------------------------
revno: 2630.4.26
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-prelocked_mode-to-push
timestamp: Fri 2008-06-06 23:19:04 +0400
message:
  WL#3726: work on review comments.
  Remove thd->locked_tables. Always store MYSQL_LOCK instances in
  thd->lock.
  Rename thd->prelocked_mode to thd->locked_tables_mode.
  Use thd->locked_tables_mode to determine if we
  are under LOCK TABLES. Update the code to not assume that
  if thd->lock is set, LOCK TABLES mode is off.
  Review comments.


sql/ha_ndbcluster_binlog.cc:
  Don't unlock the lock under LOCK TABLES (safety).
sql/handler.cc:
  There is no thd->locked_tables any more.
  Update comments.
sql/lock.cc:
  There is no thd->locked_tables any more.
sql/log.cc:
  Rename thd->prelocked_mode to thd->locked_tables_mode.
sql/set_var.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
sql/sp_head.cc:
  Rename thd->prelocked_mode to thd->locked_tables_mode.
sql/sql_base.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
  Remove thd->locked_tables.
sql/sql_cache.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
sql/sql_class.cc:
  Avoid code duplication.
  Do not release the table locks prematurely if we're under LOCK TABLES.
  Use thd->locked_tables_mode instead of thd->locked_tables.
sql/sql_class.h:
  Remove thd->locked_tables.
  Make prelocked mode a kind of LOCK TABLES mode.
  Update comments.
sql/sql_cursor.cc:
  Update comments.
sql/sql_insert.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
  Rename thd->prelocked_mode to thd->locked_tables_mode.
sql/sql_load.cc:
  Rename thd->prelocked_mode to thd->locked_tables_mode.
sql/sql_parse.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
  Remove thd->locked_tables.
sql/sql_partition.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
sql/sql_rename.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
sql/sql_select.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
sql/sql_table.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
sql/sql_trigger.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
sql/sql_update.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
sql/sql_view.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.
storage/myisam/ha_myisam.cc:
  Use thd->locked_tables_mode to determine if we are under LOCK TABLES.

------------------------------------------------------------
revno: 2630.4.25
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Fri 2008-06-06 15:32:48 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.

  Clarified some comments explaining control flow in
  prepare_for_repair().

------------------------------------------------------------
revno: 2630.4.24
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Fri 2008-06-06 14:28:58 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.

  Get rid of upgradability and priority attributes of
  metadata lock requests by replacing them with two
  new types of lock requests MDL_SHARED_UPGRADABLE and
  MDL_SHARED_HIGH_PRIO correspondingly.

------------------------------------------------------------
revno: 2630.4.22
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Thu 2008-06-05 22:06:48 +0400
message:
  WL#3726 "DDL locking for all metadata objects"

  After review fixes in progress.

  Moved code checking that current lock request can be satisfied
  given the current state of individual or global metadata lock
  to separate well-documented functions.


sql/mdl.cc:
  Moved code.

------------------------------------------------------------
revno: 2630.8.3
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w4
timestamp: Thu 2008-06-05 10:48:36 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After-review fixes in progress.

  Adjust some comments that were using old terminology
  (name locks instead of exclusive metadata locks), brought
  some of them up-to-date with current situation in code.


sql/sql_base.cc:
  Adjusted comments to use proper terminology.
sql/sql_delete.cc:
  Adjusted comments to use proper terminology.
sql/sql_handler.cc:
  Adjusted comments to use proper terminology.
sql/sql_partition.cc:
  Adjusted comments to use proper terminology also fixed
  one comment to correspond to what really happens in code.
sql/sql_show.cc:
  Adjusted comments to use proper terminology.
sql/sql_table.cc:
  Adjusted comments to use proper terminology, brought
   one of them up-to-date with current situation.
sql/sql_trigger.cc:
  Adjusted comments to use proper terminology.
sql/table.h:
  Removed two unused members of TABLE_SHARE struct.

----------------------------------------------------------
revno: 2630.2.20
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-runtime
timestamp: Fri 2008-06-27 20:10:42 +0400
message:
  Fix a regression introduced by WL#3726 when a table was left in the
  table cache after DROP DATABASE.
  Implementation of DROP DATABASE reads a list of files in the database
  directory and constructs from it the list of tables to be dropped.
  If the filesystem is case-insensitive and case-preserving, the
  table names should be lowercased, because the same has been done
  when entries for them were inserted into the table cache.
  Skipping this step will lead to orphaned TABLEs left in the table cache.
  Fixes lowercase_table2 failure on powermacg5.


sql/sql_db.cc:
  Lowercase the table name, it's used to construct the table cache
  key.

------------------------------------------------------------
revno: 2630.4.20
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Wed 2008-06-04 16:27:06 +0400
message:
  WL#3726 "DDL locking for all metadata objects"

  After review fixes in progress.

  Got rid of TABLE_LIST::mdl_upgradable member and related functions
  by using special flag which to be passed to open_table() which
  asks it to take upgradable metadata lock on table being opened.


sql/mysql_priv.h:
  Added one more argument to open_n_lock_single_table() call to be
  able to pass flags to open_table() and mysql_lock_tables() called
  by it.
  Added new flag for controlling open_table() behavior asks it to
  take upgradable metadata locks on tables open for write.
sql/sql_base.cc:
  Added new flag for controlling open_table() behavior asks it to
  take upgradable metadata locks on tables open for write.
  This allowed us to get rid of TABLE_LIST::mdl_upgradable member.
  Added one more argument to open_n_lock_single_table() call to be
  able to pass flags to open_table() and mysql_lock_tables() called
  by it.
sql/sql_insert.cc:
  Added one more argument to open_n_lock_single_table() call to be
  able to pass flags to open_table() and mysql_lock_tables() called
  by it.
sql/sql_parse.cc:
  Got rid of TABLE_LIST::mdl_upgradable member by using special flag
  which to be passed to open_table() which asks it to take
  upgradable metadata lock on table being opened.  As result also
  got rid of adjust_mdl_locks_upgradability() function.
sql/sql_table.cc:
  Got rid of TABLE_LIST::mdl_upgradable member and related functions
  by using special flag which to be passed to open_table() which
  asks it to take upgradable metadata lock on table being opened.
sql/sql_view.cc:
  Got rid of TABLE_LIST::mdl_upgradable member and related functions
  by using special flag which to be passed to open_table() which
  asks it to take upgradable metadata lock on table being opened.
sql/table.h:
  Got rid of TABLE_LIST::mdl_upgradable member and related functions
  by using special flag which to be passed to open_table() which
  asks it to take upgradable metadata lock on table being opened.

---------------------------------------------
2630.7.3 Konstantin Osipov       2008-06-02
        Various style changes preceding the removal of reopen_table().
(Post-review fixes for WL#3726).


sql/event_db_repository.cc:
  Update to use the new signature of TABLE_LIST::init_one_table().
sql/mysql_priv.h:
  Move close_cached_table() and wait_while_table_is_used()
  to sql_base.cc.
sql/sql_base.cc:
  Move close_cached_table() and wait_while_table_is_used()
  from sql_table.cc.
sql/sql_table.cc:
  Move close_cached_table() and wait_while_table_is_used()
  to sql_base.cc.
sql/table.h:
  Update the signature of TABLE_LIST::init_one_table().

---------------------------------------------------------
2630.7.2 Konstantin Osipov       2008-06-02
         Fix alignment in sql_table.cc (no other changes).


sql/sql_table.cc:
  Fix alignment (no other changes).

------------------------------------------------------------
revno: 2630.4.18
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Tue 2008-06-03 21:07:58 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.

  Now during upgrading/downgrading metadata locks we deal with
  individual metadata lock requests rather than with all requests
  for this object in the context. This makes API a bit more clear
  and makes adjust_mdl_locks_upgradability() much nicer.


sql/lock.cc:
  lock_table_names():
    Set TABLE_LIST::mdl_lock_data when allocating new metadata
    lock request object for table list element.
sql/mdl.cc:
  Now during upgrading/downgrading metadata locks we deal with
  individual metadata lock requests rather than with all
  requests for this object in the context. Adjusted upgrade/
  downgrade functions accordingly.
  We also got rid of mdl_release_exclusive_locks() and
  now release locks individually. To simplify this process
  mdl_release_all_locks_for_name() was introduced.
sql/mdl.h:
  Now during upgrading/downgrading metadata locks we deal with
  individual metadata lock requests rather than with all
  requests for this object in the context. Adjusted upgrade/
  downgrade functions accordingly.
  We also got rid of mdl_release_exclusive_locks() and
  now release locks individually. To simplify this process
  mdl_release_all_locks_for_name() was introduced.
sql/sql_base.cc:
  Now during upgrading/downgrading metadata locks we deal with
  individual metadata lock requests rather than with all
  requests for this object in the context.
  We also got rid of mdl_release_exclusive_locks() and
  now release locks individually.
sql/sql_parse.cc:
  adjust_mdl_locks_upgradability() is much simplier now due to the
  fact that now during upgrading/downgrading metadata locks we
  deal with individual metadata lock requests rather than with
  all requests for this object in the context.
sql/sql_table.cc:
  Now during upgrading/downgrading metadata locks we deal with
  individual metadata lock requests rather than with all
  requests for this object in the context. Adjusted upgrade/
  downgrade functions accordingly.
  We also got rid of mdl_release_exclusive_locks() and
  now release locks individually. To simplify this process
  mdl_release_all_locks_for_name() was introduced.
sql/sql_trigger.cc:
  ow during upgrading/downgrading metadata locks we deal with
  individual metadata lock requests rather than with all
  requests for this object in the context.

------------------------------------------------------------
revno: 2630.4.17
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Thu 2008-05-29 16:52:56 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.

  "The great correction of names".

  Renamed MDL_LOCK and MDL_LOCK_DATA classes to make usage of
  these names in metadata locking subsystem consistent with
  other parts of server (i.e. thr_lock.cc). Now we MDL_LOCK_DATA
  corresponds to request for a lock and MDL_LOCK to the lock
  itself. Adjusted code in MDL subsystem and other places
  using these classes accordingly.
  Did similar thing for GLOBAL_MDL_LOCK_DATA class and also
  changed name of its members to correspond to names of
  MDL_LOCK_DATA members.
  Finally got rid of usage of one letter variables in MDL
  code since it makes code harder to search in (according
  to reviewer).

------------------------------------------------------------
revno: 2630.4.16
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Thu 2008-05-29 09:45:02 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review changes in progress.

  Tweaked some comments and did some renames to
  avoid ambiguites.


sql/mysql_priv.h:
  Removed name_lock_locked_table() function.
sql/sql_base.cc:
  Got rid of name_lock_locked_table() function after replacing
  the only call to it with its body.
  Simplified open_table() code by making "action" argument
  mandatory (i.e. one now should always pass non-0 pointer
  in this argument).
  Renamed TABLE_LIST::open_table_type to open_type to
  avoid confusing it with type of table.
  Adjusted comments according to review.
sql/sql_handler.cc:
  Added comment clarifying in which cases we can have TABLE::mdl_lock
  set to 0.
sql/sql_insert.cc:
  Now the 4th argument of open_table() is mandatory (it makes
  no sense to complicate open_table() code when we can simply
  pass dummy variable).
sql/sql_parse.cc:
  Renamed TABLE_LIST::open_table_type to open_type to
  avoid confusing it with type of table.
sql/sql_prepare.cc:
  Renamed TABLE_LIST::open_table_type to open_type to
  avoid confusing it with type of table.
sql/sql_table.cc:
  Now the 4th argument of open_table() is mandatory (it makes
  no sense to complicate open_table() code when we can simply
  pass dummy variable).
sql/sql_trigger.cc:
  Replaced the only call to name_lock_locked_table() function
  with its body.
sql/sql_view.cc:
  Renamed TABLE_LIST::open_table_type to open_type to
  avoid confusing it with type of table.
sql/table.h:
  Renamed TABLE_LIST::open_table_type to open_type (to
  avoid confusing it with type of table) and improved
  comments describing this member.

------------------------------------------------------------
revno: 2630.4.14
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Wed 2008-05-28 12:16:03 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress. Removed unused code and
  adjusted names of functions/methods to better reflect
  their current function.


sql/mysql_priv.h:
  Changed names of close_data_files_and_morph_locks() and
  close_handle_and_leave_table_as_lock() to better reflect
  their current function (locking is now responsibility
  of metadata locking subsystem).
sql/sql_base.cc:
  Changed names of close_data_files_and_morph_locks() and
  close_handle_and_leave_table_as_lock() to better reflect
  their current function (locking is now responsibility
  of metadata locking subsystem). Also adjusted comments
  describing these functions.
  Got rid of TABLE::open_placeholder since it is no longer
  used (its value is never read anywhere).
  TABLE::needs_reopen_or_name_lock() was renamed to needs_reopen()
  since we no longer use name-locks
sql/sql_handler.cc:
  TABLE::needs_reopen_or_name_lock() was renamed to needs_reopen()
  since we no longer use name-locks.
sql/sql_insert.cc:
  TABLE::needs_reopen_or_name_lock() was renamed to needs_reopen()
  since we no longer use name-locks
sql/sql_partition.cc:
  Changed name of close_data_files_and_morph_locks() to
  better reflect its current function (locking is now
  responsibility of metadata locking subsystem).
sql/sql_table.cc:
  Changed names of close_data_files_and_morph_locks() and
  close_handle_and_leave_table_as_lock() to better reflect
  their current function (locking is now responsibility
  of metadata locking subsystem).
  Got rid of TABLE::open_placeholder since it is no longer
  used.
sql/sql_trigger.cc:
  Changed name of close_data_files_and_morph_locks() to
  better reflect its current function (locking is now
  responsibility of metadata locking subsystem).
sql/table.h:
  Got rid of TABLE::open_placeholder which is no longer used
  altough its value was set in several places no code reads it).
  Removed unused TABLE::is_name_opened() method.
  Finally TABLE::needs_reopen_or_name_lock() was renamed to
  needs_reopen() since we no longer use name-locks.

------------------------------------------------------------
revno: 2630.4.13
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Wed 2008-05-28 12:07:30 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.

  Get rid of remove_table_from_cache() function since it was
  doing two things at once -- waiting while no one uses particular
  table (now job of metadata locking) and removing TABLE/TABLE_SHARE
  instances from table definition cache (now job of
  expel_table_from_cache()).



sql/mysql_priv.h:
  Got rid of remove_table_from_cache() function. Now one
          should use exclusive metadata lock for waiting until all
          other connections will stop using particular table and
          use expel_table_from_cache() for removing table instances
          and table share from table definition cache.
          Removed unused mysql_wait_completed_table() function.
sql/sql_base.cc:
  Got rid of remove_table_from_cache() function. Now one
  should use exclusive metadata lock for waiting until all
  other connections will stop using particular table and
  use expel_table_from_cache() for removing table instances
  and table share from table definition cache.
          Removed unused mysql_wait_completed_table() function.
sql/sql_table.cc:
  Get rid of two last places where we use remove_table_from_cache()
  by using wait_while_table_is_used() (which uses metadata locks)
  and close_cached_tables() instead.

-------------------------------------------------------------------
revno: 2630.6.6
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-3726
timestamp: Tue 2008-05-27 16:15:44 +0400
message:
Implement code review fixes for WL#3726 "DDL locking for all
metadata objects": cleanup the code from share->mutex
acquisitions, which are now obsolete.

sql/ha_partition.cc:
  Rename share->mutex to share->LOCK_ha_data. The mutex never
  protected the entire share. The right way to protect a share
  is to acquire an MDL lock.
sql/ha_partition.h:
  Rename share->mutex to share->LOCK_ha_data.
sql/sql_base.cc:
  Remove LOCK_table_share. Do not acquire share->mutex when
  deleting a table share or incrementing its ref_count.
  All these operations are and must continue to be protected by LOCK_open
  and respective MDL locks.
sql/sql_view.cc:
  Remove acquisition of share->mutex when incrementing share->ref_count.
sql/table.cc:
  Simplify release_table_shar() by removing dead code related
  to share->mutex from it.
sql/table.h:
  Rename TABLE_SHARE::mutex to TABLE_SHARE::LOCK_ha_data
  to better reflect its purpose.
storage/myisam/ha_myisam.cc:
  Rename share->mutex to share->LOCK_ha_data.

------------------------------------------------------------
revno: 2630.6.1
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-3726
timestamp: Tue 2008-05-27 13:45:34 +0400
message:
  Remove an unused argument from release_table_share().
  Remove unused members from TABLE_SHARE struct.
  Review comments in scope of WL#3726 "DDL locking for all metadata 
  objects"

sql/mysql_priv.h:
  Update declaration.
sql/sql_base.cc:
  Upate declaration and the comment (release_share()).
sql/sql_plist.h:
  A cosmetic change, is_empty() is a const method.
sql/sql_table.cc:
  Update to use the new declaration of release_table_share().
sql/sql_view.cc:
  Update to use the new declaration of release_table_share().
sql/table.cc:
  Update to use the new declaration of release_table_share().
  Remove dead code.
sql/table.h:
  Remove unused members of TABLE.

------------------------------------------------------------
revno: 2630.4.11
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Tue 2008-05-27 21:31:53 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.

  Changed mysql_lock_tables() to be no longer responsible for
  reopening table if waiting for the lock on it was aborted.
  This allows to get rid of several annoying functions.


sql/ha_ndbcluster_binlog.cc:
  lock_tables() now also accepts set of options to be passed to
  mysql_lock_tables().
sql/lock.cc:
  Changed mysql_lock_tables() always requests caller to reopen
  table instead doing this on its own when waiting for lock was
  aborted. This allows us to get rid of several functions which
  were used in rare cases and significantly complicated our life.
sql/log_event_old.cc:
  lock_tables() now also accepts set of options to be passed
  to mysql_lock_tables().
sql/mysql_priv.h:
  Now mysql_lock_tables() always requests caller to reopen
  table instead doing this on its own when waiting for lock was
  aborted. So we no longer need wait_for_tables() and
  table_is_used() functions and MYSQL_LOCK_NOTIFY_IF_NEED_REOPEN
  flag.
  open_and_lock_table_derived() and lock_tables() now accept
  options to be passed to open_tables() and mysql_lock_tables()
  calls.
sql/sql_base.cc:
  Since now mysql_lock_tables() always requests caller to
  reopen table instead doing this on its own when waiting for
  lock was aborted we no longer need wait_for_tables(),
  table_is_used() and close_old_data_files() functions.
  open_and_lock_table_derived() and lock_tables() now accept
  options to be passed to open_tables() and mysql_lock_tables()
  calls. This was needed in order to get rid of redundant code
  in open_system_tables_for_read() function.
sql/sql_handler.cc:
  mysql_lock_tables() is now always requests reopen if waiting
  for lock is aborted. MYSQL_LOCK_NOTIFY_IF_NEED_REOPEN flag
  was removed.
sql/sql_insert.cc:
  handle_delayed_insert():
  Since mysql_lock_tables() is no longer responsible for
  reopening tables when waiting for lock was aborted we have
  to handle such situation outside of this function. To simplify
  this extracted code opening table for delayed insert thread to
  separate method of Delayed_insert class.
sql/sql_update.cc:
  lock_tables() now also accepts set of options to be passed
  to mysql_lock_tables().

------------------------------------------------------------
revno: 2630.4.10
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Mon 2008-05-26 15:11:26 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review changes in progress.
  Implemented some renames suggested by reviewer.


sql/mdl.cc:
  Renamed:
    MDL_LOCK_DATA::users -> lock_count
    MDL_LOCK_DATA::has_no_other_users() -> has_one_lock()
    MDL_LOCK::upgradable -> is_upgradable
    Moved variables used in global metadata lock implementation
    to separate strucuture.
sql/mdl.h:
  Renamed MDL_LOCK::upgradable to is_upgradable.

----------------------------------------------------------------
2630.4.9 Dmitry Lenev	2008-05-26
         WL#3726 "DDL locking for all metadata objects".
        
         After review fixes in progress. Adjusted test case
         according to review.


mysql-test/suite/rpl/r/rpl_view_multi.result:
  Changed test case to check that statements are replicated
  properly instead of directly inspecting binary log. Also
  made result file more readable by adding echo there it
  was appropriate. Moved test case to "rpl" suite.
mysql-test/suite/rpl/t/rpl_view_multi.test:
  Changed test case to check that statements are replicated
  properly instead of directly inspecting binary log. Also
  made result file more readable by adding echo there it
  was appropriate. Moved test case to "rpl" suite.

------------------------------------------------------------
revno: 2630.4.7
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sun 2008-05-25 11:19:02 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  Fixed silly mistake in test case which caused sporadic
  kill.test failures.

mysql-test/t/kill.test:
  Fixed silly mistake in several places where I was supposed to
  be waiting for certain state of connection I actually forgot
  to invoke wait_condition.inc script altough set appropriate
  variable. Indeed this caused sporadical test failures.

Backport of:
------------------------------------------------------------
revno: 2630.4.1
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Fri 2008-05-23 17:54:03 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.
------------------------------------------------------------

This is the first patch in series. It transforms the metadata 
locking subsystem to use a dedicated module (mdl.h,cc). No 
significant changes in the locking protocol. 
The import passes the test suite with the exception of 
deprecated/removed 6.0 features, and MERGE tables. The latter
are subject to a fix by WL#4144.
Unfortunately, the original changeset comments got lost in a merge,
thus this import has its own (largely insufficient) comments.

This patch fixes Bug#25144 "replication / binlog with view breaks".
Warning: this patch introduces an incompatible change:
Under LOCK TABLES, it's no longer possible to FLUSH a table that 
was not locked for WRITE.
Under LOCK TABLES, it's no longer possible to DROP a table or
VIEW that was not locked for WRITE.

******
Backport of:
------------------------------------------------------------
revno: 2630.4.2
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sat 2008-05-24 14:03:45 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.

******
Backport of:
------------------------------------------------------------
revno: 2630.4.3
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sat 2008-05-24 14:08:51 +0400
message:
  WL#3726 "DDL locking for all metadata objects"

  Fixed failing Windows builds by adding mdl.cc to the lists
  of files needed to build server/libmysqld on Windows.

******
Backport of:
------------------------------------------------------------
revno: 2630.4.4
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sat 2008-05-24 21:57:58 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  Fix for assert failures in kill.test which occured when one
  tried to kill ALTER TABLE statement on merge table while it
  was waiting in wait_while_table_is_used() for other connections
  to close this table.

  These assert failures stemmed from the fact that cleanup code
  in this case assumed that temporary table representing new
  version of table was open with adding to THD::temporary_tables
  list while code which were opening this temporary table wasn't
  always fulfilling this.

  This patch changes code that opens new version of table to
  always do this linking in. It also streamlines cleanup process
  for cases when error occurs while we have new version of table
  open.

******
WL#3726 "DDL locking for all metadata objects"
Add libmysqld/mdl.cc to .bzrignore.
******
Backport of:
------------------------------------------------------------
revno: 2630.4.6
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sun 2008-05-25 00:33:22 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  Addition to the fix of assert failures in kill.test caused by
  changes for this worklog.


Make sure we close the new table only once.

.bzrignore:
  Add libmysqld/mdl.cc
libmysqld/CMakeLists.txt:
  Added mdl.cc to the list of files needed for building of libmysqld.
libmysqld/Makefile.am:
  Added files implementing new meta-data locking subsystem to the server.
mysql-test/include/handler.inc:
  Use separate connection for waiting while threads performing DDL
  operations conflicting with open HANDLER tables reach blocked
  state. This is required because now we check and close tables open
  by HANDLER statements in this connection conflicting with DDL in
  another each time open_tables() is called and thus select from I_S
  which is used for waiting will unblock DDL operations if issued
  from connection with open HANDLERs.
mysql-test/r/create.result:
  Adjusted test case after change in implementation of CREATE TABLE
  ... SELECT.  We no longer have special check in open_table() which
  catches the case when we select from the table created. Instead we
  rely on unique_table() call which happens after opening and
  locking all tables.
mysql-test/r/flush.result:
  FLUSH TABLES WITH READ LOCK can no longer happen under LOCK
  TABLES.  Updated test accordingly.
mysql-test/r/flush_table.result:
  Under LOCK TABLES we no longer allow to do FLUSH TABLES for tables
  locked for read. Updated test accordingly.
mysql-test/r/handler_innodb.result:
  Use separate connection for waiting while threads performing DDL
  operations conflicting with open HANDLER tables reach blocked
  state. This is required because now we check and close tables open
  by HANDLER statements in this connection conflicting with DDL in
  another each time open_tables() is called and thus select from I_S
  which is used for waiting will unblock DDL operations if issued
  from connection with open HANDLERs.
mysql-test/r/handler_myisam.result:
  Use separate connection for waiting while threads performing DDL
  operations conflicting with open HANDLER tables reach blocked
  state. This is required because now we check and close tables open
  by HANDLER statements in this connection conflicting with DDL in
  another each time open_tables() is called and thus select from I_S
  which is used for waiting will unblock DDL operations if issued
  from connection with open HANDLERs.
mysql-test/r/information_schema.result:
  Additional test for WL#3726 "DDL locking for all metadata
  objects".  Check that we use high-priority metadata lock requests
  when filling I_S tables.
  
  Rearrange tests to match 6.0 better (fewer merge conflicts).
mysql-test/r/kill.result:
  Added tests checking that DDL and DML statements waiting for
  metadata locks can be interrupted by KILL command.
mysql-test/r/lock.result:
  One no longer is allowed to do DROP VIEW under LOCK TABLES even if
  this view is locked by LOCK TABLES. The problem is that in such
  situation write locks on view are not mutually exclusive so
  upgrading metadata lock which is required for dropping of view
  will lead to deadlock.
mysql-test/r/partition_column_prune.result:
  Update results (same results in 6.0), WL#3726
mysql-test/r/partition_pruning.result:
  Update results (same results in 6.0), WL#3726
mysql-test/r/ps_ddl.result:
  We no longer invalidate prepared CREATE TABLE ... SELECT statement
  if target table changes. This is OK since it is not strictly
  necessary.
  
  
  The first change is wrong, is caused by FLUSH TABLE
  now flushing all unused tables. This is a regression that
  Dmitri fixed in 6.0 in a follow up patch.
mysql-test/r/sp.result:
  Under LOCK TABLES we no longer allow accessing views which were
  not explicitly locked. To access view we need to obtain metadata
  lock on it and doing this under LOCK TABLES may lead to deadlocks.
mysql-test/r/view.result:
  One no longer is allowed to do DROP VIEW under LOCK TABLES even if
  this view is locked by LOCK TABLES. The problem is that in such
  situation even "write locks" on view are not mutually exclusive so
  upgrading metadata lock which is required for dropping of view
  will lead to deadlock
mysql-test/r/view_grant.result:
  ALTER VIEW implementation was changed to open a view only after
  checking that user which does alter has appropriate privileges on
  it. This means that in case when user's privileges are
  insufficient for this we won't check that new view definer is the
  same as original one or user performing alter has SUPER privilege.
  Adjusted test case accordingly.
mysql-test/r/view_multi.result:
  Added test case for bug#25144 "replication / binlog with view
  breaks".
mysql-test/suite/rpl/t/disabled.def:
  Disable test for deprecated features (they don't work with new MDL).
mysql-test/t/create.test:
  Adjusted test case after change in implementation of CREATE TABLE
  ... SELECT.  We no longer have special check in open_table() which
  catches the case when we select from the table created. Instead we
  rely on unique_table() call which happens after opening and
  locking all tables.
mysql-test/t/disabled.def:
  Disable merge.test, subject of WL#4144
mysql-test/t/flush.test:
  
  FLUSH TABLES WITH READ LOCK can no longer happen under LOCK
  TABLES.  Updated test accordingly.
mysql-test/t/flush_table.test:
  Under LOCK TABLES we no longer allow to do FLUSH TABLES for tables
  locked for read. Updated test accordingly.
mysql-test/t/information_schema.test:
  Additional test for WL#3726 "DDL locking for all metadata
  objects".  Check that we use high-priority metadata lock requests
  when filling I_S tables.
  
  Rearrange the results for easier merges with 6.0.
mysql-test/t/kill.test:
  Added tests checking that DDL and DML statements waiting for
  metadata locks can be interrupted by KILL command.
mysql-test/t/lock.test:
  One no longer is allowed to do DROP VIEW under LOCK TABLES even if
  this view is locked by LOCK TABLES. The problem is that in such
  situation write locks on view are not mutually exclusive so
  upgrading metadata lock which is required for dropping of view
  will lead to deadlock.
mysql-test/t/lock_multi.test:
  Adjusted test case to the changes of status in various places
  caused by change in implementation FLUSH TABLES WITH READ LOCK,
  which is now takes global metadata lock before flushing tables and
  therefore waits on at these places.
mysql-test/t/ps_ddl.test:
  We no longer invalidate prepared CREATE TABLE ... SELECT statement
  if target table changes. This is OK since it is not strictly
  necessary.
  
  
  The first change is wrong, is caused by FLUSH TABLE
  now flushing all unused tables. This is a regression that
  Dmitri fixed in 6.0 in a follow up patch.
mysql-test/t/sp.test:
  Under LOCK TABLES we no longer allow accessing views which were
  not explicitly locked. To access view we need to obtain metadata
  lock on it and doing this under LOCK TABLES may lead to deadlocks.
mysql-test/t/trigger_notembedded.test:
  Adjusted test case to the changes of status in various places
  caused by change in implementation FLUSH TABLES WITH READ LOCK,
  which is now takes global metadata lock before flushing tables and
  therefore waits on at these places.
mysql-test/t/view.test:
  One no longer is allowed to do DROP VIEW under LOCK TABLES even if
  this view is locked by LOCK TABLES. The problem is that in such
  situation even "write locks" on view are not mutually exclusive so
  upgrading metadata lock which is required for dropping of view
  will lead to deadlock.
mysql-test/t/view_grant.test:
  ALTER VIEW implementation was changed to open a view only after
  checking that user which does alter has appropriate privileges on
  it. This means that in case when user's privileges are
  insufficient for this we won't check that new view definer is the
  same as original one or user performing alter has SUPER privilege.
  Adjusted test case accordingly.
mysql-test/t/view_multi.test:
  Added test case for bug#25144 "replication / binlog with view
  breaks".
sql/CMakeLists.txt:
  Added mdl.cc to the list of files needed for building of server.
sql/Makefile.am:
  Added files implementing new meta-data locking subsystem to the
  server.
sql/event_db_repository.cc:
  
  Allocate metadata lock requests objects (MDL_LOCK) on execution
  memory root in cases when TABLE_LIST objects is also allocated
  there or on stack.
sql/ha_ndbcluster.cc:
  Adjusted code to work nicely with new metadata locking subsystem.
  close_cached_tables() no longer has wait_for_placeholder argument.
  Instead of relying on this parameter and related behavior FLUSH
  TABLES WITH READ LOCK now takes global shared metadata lock.
sql/ha_ndbcluster_binlog.cc:
  Adjusted code to work with new metadata locking subsystem.
  close_cached_tables() no longer has wait_for_placeholder argument.
  Instead of relying on this parameter and related behavior FLUSH
  TABLES WITH READ LOCK now takes global shared metadata lock.
sql/handler.cc:
  update_frm_version():
    Directly update TABLE_SHARE::mysql_version member instead of
    going through all TABLE instances for this table (old code was a
    legacy from pre-table-definition-cache days).
sql/lock.cc:
  Use new metadata locking subsystem. Threw away most of functions
  related to name locking as now one is supposed to use metadata
  locking API instead.  In lock_global_read_lock() and
  unlock_global_read_lock() in order to avoid problems with global
  read lock sneaking in at the moment when we perform FLUSH TABLES
  or ALTER TABLE under LOCK TABLES and when tables being reopened
  are protected only by metadata locks we also have to take global
  shared meta data lock.
sql/log_event.cc:
  Adjusted code to work with new metadata locking subsystem.  For
  tables open by slave thread for applying RBR events allocate
  memory for lock request object in the same chunk of memory as
  TABLE_LIST objects for them. In order to ensure that we keep these
  objects around until tables are open always close tables before
  calling Relay_log_info::clear_tables_to_lock(). Use new auxiliary
  Relay_log_info::slave_close_thread_tables() method to enforce
  this.
sql/log_event_old.cc:
  Adjusted code to work with new metadata locking subsystem.  Since
  for tables open by slave thread for applying RBR events memory for
  lock request object is allocated in the same chunk of memory as
  TABLE_LIST objects for them we have to ensure that we keep these
  objects around until tables are open. To ensure this we always
  close tables before calling
  Relay_log_info::clear_tables_to_lock(). To enfore this we use
  new auxiliary Relay_log_info::slave_close_thread_tables()
  method.
sql/mdl.cc:
  Implemented new metadata locking subsystem and API described in
  WL3726 "DDL locking for all metadata objects".
sql/mdl.h:
  Implemented new metadata locking subsystem and API described in
  WL3726 "DDL locking for all metadata objects".
sql/mysql_priv.h:
  - close_thread_tables()/close_tables_for_reopen() now has one more
    argument which indicates that metadata locks should be released
    but not removed from the context in order to be used later in
    mdl_wait_for_locks() and tdc_wait_for_old_version().
  - close_cached_table() routine is no longer public.
  - Thread waiting in wait_while_table_is_used() can be now killed
    so this function returns boolean to make caller aware of such
    situation.
  - We no longer have  table cache as separate entity instead used
    and unused TABLE instances are linked to TABLE_SHARE objects in
    table definition cache.
  - Now third argument of open_table() is also used for requesting
    table repair or auto-discovery of table's new definition. So its
    type was changed from bool to enum.
  - Added tdc_open_view() function for opening view by getting its
    definition from disk (and table cache in future).
  - reopen_name_locked_table() no longer needs "link_in" argument as
    now we have exclusive metadata locks instead of dummy TABLE
    instances when this function is called.
  - find_locked_table() now takes head of list of TABLE instances
    instead of always scanning through THD::open_tables list. Also
    added find_write_locked_table() auxiliary.
  - reopen_tables(), close_cached_tables() no longer have
    mark_share_as_old and wait_for_placeholder arguments. Instead of
    relying on this parameters and related behavior FLUSH TABLES
    WITH READ LOCK now takes global shared metadata lock.
  - We no longer need drop_locked_tables() and
    abort_locked_tables().
  - mysql_ha_rm_tables() now always assume that LOCK_open is not
    acquired by caller.
  - Added notify_thread_having_shared_lock() callback invoked by
    metadata locking subsystem when acquiring an exclusive lock, for
    each thread that has a conflicting shared metadata lock.
  - Introduced expel_table_from_cache() as replacement for
    remove_table_from_cache() (the main difference is that this new
    function assumes that caller follows metadata locking protocol
    and never waits).
  - Threw away most of functions related to name locking. One should
    use new metadata locking subsystem and API instead.
sql/mysqld.cc:
  Got rid of call initializing/deinitializing table cache since now
  it is embedded into table definition cache. Added calls for
  initializing/ deinitializing metadata locking subsystem.
sql/rpl_rli.cc:
  Introduced auxiliary Relay_log_info::slave_close_thread_tables()
  method which is used for enforcing that we always close tables
  open for RBR before deallocating TABLE_LIST elements and MDL_LOCK
  objects for them.
sql/rpl_rli.h:
  Introduced auxiliary Relay_log_info::slave_close_thread_tables()
  method which is used for enforcing that we always close tables
  open for RBR before deallocating TABLE_LIST elements and MDL_LOCK
  objects for them.
sql/set_var.cc:
  close_cached_tables() no longer has wait_for_placeholder argument.
  Instead of relying on this parameter and related behavior FLUSH
  TABLES WITH READ LOCK now takes global shared metadata lock.
sql/sp_head.cc:
  For tables added to the statement's table list by prelocking
  algorithm we allocate these objects either on the same memory as
  corresponding table list elements or on THD::locked_tables_root
  (if we are building table list for LOCK TABLES).
sql/sql_acl.cc:
  Allocate metadata lock requests objects (MDL_LOCK) on execution
  memory root in cases when we use stack TABLE_LIST objects to open
  tables.  Got rid of redundant code by using unlock_locked_tables()
  function.
sql/sql_base.cc:
  Changed code to use new MDL subsystem. Got rid of separate table
  cache.  Now used and unused TABLE instances are linked to the
  TABLE_SHAREs in table definition cache.
  
  check_unused():
    Adjusted code to the fact that we no longer have separate table
    cache.  Removed dead code.
  table_def_free():
    Free TABLE instances referenced from TABLE_SHARE objects before
    destroying table definition cache.
  get_table_share():
    Added assert which ensures that noone will be able to access
    table (and its share) without acquiring some kind of metadata
    lock first.
  close_handle_and_leave_table_as_lock():
    Adjusted code to the fact that TABLE instances now are linked to
    list in TABLE_SHARE.
  list_open_tables():
    Changed this function to use table definition cache instead of
    table cache.
  free_cache_entry():
    Unlink freed TABLE elements from the list of all TABLE instances
    for the table in TABLE_SHARE.
  kill_delayed_thread_for_table():
    Added auxiliary for killing delayed insert threads for
    particular table.
  close_cached_tables():
    Got rid of wait_for_refresh argument as we now rely on global
    shared metadata lock to prevent FLUSH WITH READ LOCK sneaking in
    when we are reopening tables. Heavily reworked this function to
    use new MDL code and not to rely on separate table cache entity.
  close_open_tables():
    We no longer have separate table cache.
  close_thread_tables():
    Release metadata locks after closing all tables. Added skip_mdl
    argument which allows us not to remove metadata lock requests
    from the context in case when we are going to use this requests
    later in mdl_wait_for_locks() and tdc_wait_for_old_versions().
  close_thread_table()/close_table_for_reopen():
    Since we no longer have separate table cache and all TABLE
    instances are linked to TABLE_SHARE objects in table definition
    cache we have to link/unlink TABLE object to/from appropriate
    lists in the share.
  name_lock_locked_table():
   Moved redundant code to find_write_locked_table() function and
    adjusted code to the fact that wait_while_table_is_used() can
    now return with an error if our thread is killed.
  reopen_table_entry():
    We no longer need "link_in" argument as with MDL we no longer
    call this function with dummy TABLE object pre-allocated and
    added to the THD::open_tables. Also now we add newly-open TABLE
    instance to the list of share's used TABLE instances.
  table_cache_insert_placeholder():
    Got rid of name-locking legacy.
  lock_table_name_if_not_cached():
    Moved to sql_table.cc the only place where it is used. It was
    also reimplemented using new MDL API.
  open_table():
    - Reworked this function to use new MDL subsystem.
    - Changed code to deal with table definition cache directly
      instead of going through separate table cache.
    - Now third argument is also used for requesting table repair
      or auto-discovery of table's new definition. So its type was
      changed from bool to enum.
  find_locked_table()/find_write_locked_table():
    Accept head of list of TABLE objects as first argument and use
    this list instead of always searching in THD::open_tables list.
    Also added auxiliary for finding write-locked locked tables.
  reopen_table():
    Adjusted function to work with new MDL subsystem and to properly
    manuipulate with lists of used/unused TABLE instaces in
    TABLE_SHARE.
  reopen_tables():
    Removed mark_share_as_old parameter. Instead of relying on it
    and related behavior FLUSH TABLES WITH READ LOCK now takes
    global shared metadata lock. Changed code after removing
    separate table cache.
  drop_locked_tables()/abort_locked_tables():
    Got rid of functions which are no longer needed.
    unlock_locked_tables():
    Moved this function from sql_parse.cc and changed it to release
    memory which was used for allocating metadata lock requests for
    tables open and locked by LOCK TABLES.
  tdc_open_view():
    Intoduced function for opening a view by getting its definition
    from disk (and table cache in future).
  reopen_table_entry():
    Introduced function for opening table definitions while holding
    exclusive metatadata lock on it.
  open_unireg_entry():
   Got rid of this function. Most of its functionality is relocated
    to open_table() and open_table_fini() functions, and some of it
    to reopen_table_entry() and tdc_open_view(). Also code
    resposible for auto-repair and auto-discovery of tables was
    moved to separate function.
  open_table_entry_fini():
    Introduced function which contains common actions which finalize
    process of TABLE object creation.
  auto_repair_table():
    Moved code responsible for auto-repair of table being opened
    here.
  handle_failed_open_table_attempt()
    Moved code responsible for handling failing attempt to open
    table to one place (retry due to lock conflict/old version,
    auto-discovery and repair).
  open_tables():
    - Flush open HANDLER tables if they have old version of if there
      is conflicting metadata lock against them (before this moment
      we had this code in open_table()).
    - When we open view which should be processed via derived table
      on the second execution of prepared statement or stored
      routine we still should call open_table() for it in order to
      obtain metadata lock on it and prepare its security context.
    - In cases when we discover that some special handling of
      failure to open table is needed call
      handle_failed_open_table_attempt() which handles all such
      scenarios.
  open_ltable():
    Handling of various special scenarios of failure to open a table
    was moved to separate handle_failed_open_table_attempt()
    function.
  remove_db_from_cache():
    Removed this function as it is no longer used.
  notify_thread_having_shared_lock():
    Added callback which is invoked by MDL subsystem when acquiring
    an exclusive lock, for each thread that has a conflicting shared
    metadata lock.
  expel_table_from_cache():
    Introduced function for removing unused TABLE instances. Unlike
    remove_table_from_cache() it relies on caller following MDL
    protocol and having appropriate locks when calling it and thus
    does not do any waiting if table is still in use.
  tdc_wait_for_old_version():
    Added function which allows open_tables() to wait in cases when
    we discover that we should back-off due to presence of old
    version of table.
  abort_and_upgrade_lock():
    Use new MDL calls.
  mysql_wait_completed_table():
    Got rid of unused function.
  open_system_tables_for_read/for_update()/performance_schema_table():
    Allocate MDL_LOCK objects on execution memory root in cases when
    TABLE_LIST objects for corresponding tables is allocated on
    stack.
  close_performance_schema_table():
    Release metadata locks after closing tables.
  ******
  Use I_P_List for free/used tables list in the table share.
sql/sql_binlog.cc:
  Use Relay_log_info::slave_close_thread_tables() method to enforce
  that we always close tables open for RBR before deallocating
  TABLE_LIST elements and MDL_LOCK objects for them.
sql/sql_class.cc:
  Added meta-data locking contexts as part of Open_tables_state
  context.  Also introduced THD::locked_tables_root memory root
  which is to be used for allocating MDL_LOCK objects for tables in
  LOCK TABLES statement (end of lifetime for such objects is UNLOCK
  TABLES so we can't use statement or execution root for them).
sql/sql_class.h:
  Added meta-data locking contexts as part of Open_tables_state
  context.  Also introduced THD::locked_tables_root memory root
  which is to be used for allocating MDL_LOCK objects for tables in
  LOCK TABLES statement (end of lifetime for such objects is UNLOCK
  TABLES so we can't use statement or execution root for them).
  
  Note: handler_mdl_context and locked_tables_root and
  mdl_el_root will be removed by subsequent patches.
sql/sql_db.cc:
  mysql_rm_db() does not really need to call remove_db_from_cache()
  as it drops each table in the database using
  mysql_rm_table_part2(), which performs all necessary operations on
  table (definition) cache.
sql/sql_delete.cc:
  Use the new metadata locking API for TRUNCATE.
sql/sql_handler.cc:
  Changed HANDLER implementation to use new metadata locking
  subsystem.  Note that MDL_LOCK objects for HANDLER tables are
  allocated in the same chunk of heap memory as TABLE_LIST object
  for those tables.
sql/sql_insert.cc:
  mysql_insert():
    find_locked_table() now takes head of list of TABLE object as
    its argument instead of always scanning through THD::open_tables
    list.
  handle_delayed_insert():
    Allocate metadata lock request object for table open by delayed
    insert thread on execution memroot.  create_table_from_items():
    We no longer allocate dummy TABLE objects for tables being
    created if they don't exist. As consequence
    reopen_name_locked_table() no longer has link_in argument.
    open_table() now has one more argument which is not relevant for
    temporary tables.
sql/sql_parse.cc:
  - Moved unlock_locked_tables() routine to sql_base.cc and made
    available it in other files. Got rid of some redundant code by
    using this function.
  - Replaced boolean TABLE_LIST::create member with enum
    open_table_type member.
  - Use special memory root for allocating MDL_LOCK objects for
    tables open and locked by LOCK TABLES (these object should live
    till UNLOCK TABLES so we can't allocate them on statement nor
    execution memory root). Also properly set metadata lock
    upgradability attribure for those tables.
  - Under LOCK TABLES it is no longer allowed to flush tables which
    are not write-locked as this breaks metadata locking protocol
    and thus potentially might lead to deadlock.
  - Added auxiliary adjust_mdl_locks_upgradability() function.
sql/sql_partition.cc:
  Adjusted code to the fact that reopen_tables() no longer has
  "mark_share_as_old" argument. Got rid of comments which are no
  longer true.
sql/sql_plist.h:
  Added I_P_List template class for parametrized intrusive doubly
  linked lists and I_P_List_iterator for corresponding iterator.
  Unlike for I_List<> list elements of such list can participate in
  several lists. Unlike List<> such lists are doubly-linked and
  intrusive.
sql/sql_plugin.cc:
  Allocate metadata lock requests objects (MDL_LOCK) on execution
  memory root in cases when we use stack TABLE_LIST objects to open
  tables.
sql/sql_prepare.cc:
  Replaced boolean TABLE_LIST::create member with enum
  open_table_type member.  This allows easily handle situation in
  which instead of opening the table we want only to take exclusive
  metadata lock on it.
sql/sql_rename.cc:
  Use new metadata locking subsystem in implementation of RENAME
  TABLE.
sql/sql_servers.cc:
  Allocate metadata lock requests objects (MDL_LOCK) on execution
  memory root in cases when we use stack TABLE_LIST objects to open
  tables. Got rid of redundant code by using unlock_locked_tables()
  function.
sql/sql_show.cc:
  Acquire shared metadata lock when we are getting information for
  I_S table directly from TABLE_SHARE without doing full-blown table
  open.  We use high priority lock request in this situation in
  order to avoid deadlocks.
  Also allocate metadata lock requests objects (MDL_LOCK) on
  execution memory root in cases when TABLE_LIST objects are also
  allocated there
sql/sql_table.cc:
  mysql_rm_table():
    Removed comment which is no longer relevant.
  mysql_rm_table_part2():
    Now caller of mysql_ha_rm_tables() should not own LOCK_open.
    Adjusted code to use new metadata locking subsystem instead of
    name-locks.
  lock_table_name_if_not_cached():
    Moved this function from sql_base.cc to this file and
    reimplemented it using metadata locking API.
  mysql_create_table():
    Adjusted code to use new MDL API.
  wait_while_table_is_used():
    Changed function to use new MDL subsystem. Made thread waiting
    in it killable (this also led to introduction of return value so
    caller can distinguish successful executions from situations
    when waiting was aborted).
  close_cached_tables():
    Thread waiting in this function is killable now. As result it
    has return value for distinguishing between succes and failure.
    Got rid of redundant boradcast_refresh() call.
  prepare_for_repair():
    Use MDL subsystem instead of name-locks.
  mysql_admin_table():
    mysql_ha_rm_tables() now always assumes that caller doesn't own
    LOCK_open.
  mysql_repair_table():
    We should mark all elements of table list as requiring
    upgradable metadata locks.
  mysql_create_table_like():
    Use new MDL subsystem instead of name-locks.
  create_temporary_tables():
    We don't need to obtain metadata locks when creating temporary
    table.
  mysql_fast_or_online_alter_table():
    Thread waiting in wait_while_table_is_used() is now killable.
  mysql_alter_table():
    Adjusted code to work with new MDL subsystem and to the fact
    that threads waiting in what_while_table_is_used() and
    close_cached_table() are now killable.
sql/sql_test.cc:
  We no longer have separate table cache. TABLE instances are now
  associated with/linked to TABLE_SHARE objects in table definition
  cache.
sql/sql_trigger.cc:
  Adjusted code to work with new metadata locking subsystem.  Also
  reopen_tables() no longer has mark_share_as_old argument (Instead
  of relying on this parameter and related behavior FLUSH TABLES
  WITH READ LOCK now takes global shared metadata lock).
sql/sql_udf.cc:
  Allocate metadata lock requests objects (MDL_LOCK) on execution
  memory root in cases when we use stack TABLE_LIST objects to open
  tables.
sql/sql_update.cc:
  Adjusted code to work with new meta-data locking subsystem.
sql/sql_view.cc:
  Added proper meta-data locking to implementations of
  CREATE/ALTER/DROP VIEW statements. Now we obtain exclusive
  meta-data lock on a view before creating/ changing/dropping it.
  This ensures that all concurrent statements that use this view
  will finish before our statement will proceed and therefore we
  will get correct order of statements in the binary log.
  Also ensure that TABLE_LIST::mdl_upgradable attribute is properly
  propagated for underlying tables of view.
sql/table.cc:
  Added auxiliary alloc_mdl_locks() function for allocating metadata
  lock request objects for all elements of table list.
sql/table.h:
  TABLE_SHARE:
    Got rid of unused members. Introduced members for storing lists
    of used and unused TABLE objects for this share.
  TABLE:
    Added members for linking TABLE objects into per-share lists of
    used and unused TABLE instances. Added member for holding
    pointer to metadata lock for this table.
  TABLE_LIST:
    Replaced boolean TABLE_LIST::create member with enum
    open_table_type member.  This allows easily handle situation in
    which instead of opening the table we want only to take
    exclusive meta-data lock on it (we need this in order to handle
    ALTER VIEW and CREATE VIEW statements).
    Introduced new mdl_upgradable member for marking elements of
    table list for which we need to take upgradable shared metadata
    lock instead of plain shared metadata lock.  Added pointer for
    holding pointer to MDL_LOCK for the table.
  Added auxiliary alloc_mdl_locks() function for allocating metadata
  lock requests objects for all elements of table list.  Added
  auxiliary set_all_mdl_upgradable() function for marking all
  elements in table list as requiring upgradable metadata locks.
storage/myisammrg/ha_myisammrg.cc:
  Allocate MDL_LOCK objects for underlying tables of MERGE table.
  To be reworked once Ingo pushes his patch for WL4144.

------------------------------------------------------------
revno: 3559
committer: Davi Arnaut <Davi.Arnaut@Sun.COM>
branch nick: mysql-pe
timestamp: Fri 2009-08-28 15:23:16 -0300
message:
Break down a large and obnoxious "if" statement. Multiple "if" statements
makes it easy to understand and follow the code (specially in a debugger).

sql/sql_base.cc:
  Break down a large and obnoxious "if" statement. Multiple "if" statements
  makes it easy to understand and follow the code (specially in a debugger).

No commit message

----------------------------------------------------------------------
ChangeSet@1.2571, 2008-04-08 12:30:06+02:00, vvaintroub@wva. +122 -0
  Bug#32082 : definition of VOID in my_global.h conflicts with Windows
  SDK headers
  
  VOID macro is now removed. Its usage is replaced with void cast.
  In some cases, where cast does not make much sense (pthread_*, printf, 
  hash_delete, my_seek), cast is ommited.


client/mysqladmin.cc:
  Bug#32082 : remove VOID macro
client/mysqldump.c:
  Bug#32082 : remove VOID macro
client/mysqlimport.c:
  Bug#32082 : remove VOID macro
client/mysqlslap.c:
  Bug#32082 : remove VOID macro
client/mysqltest.cc:
  Bug#32082 : remove VOID macro
client/sql_string.cc:
  Bug#32082 : remove VOID macro
extra/comp_err.c:
  Bug#32082 : remove VOID macro
extra/replace.c:
  Bug#32082 : remove VOID macro
include/my_alarm.h:
  Bug#32082 : remove VOID macro
include/my_global.h:
  Bug#32082 : remove VOID macro
libmysql/libmysql.c:
  Bug#32082 : remove VOID macro
mysys/errors.c:
  Bug#32082 : remove VOID macro
mysys/hash.c:
  Bug#32082 : remove VOID macro
mysys/mf_iocache2.c:
  Bug#32082 : remove VOID macro
mysys/mf_loadpath.c:
  Bug#32082 : remove VOID macro
mysys/mf_path.c:
  Bug#32082 : remove VOID macro
mysys/my_append.c:
  Bug#32082 : remove VOID macro
mysys/my_clock.c:
  Bug#32082 : remove VOID macro
mysys/my_copy.c:
  Bug#32082 : remove VOID macro
mysys/my_fstream.c:
  Bug#32082 : remove VOID macro
mysys/my_getwd.c:
  Bug#32082 : remove VOID macro
mysys/my_lib.c:
  Bug#32082 : remove VOID macro
mysys/my_lockmem.c:
  Bug#32082 : remove VOID macro
mysys/my_pthread.c:
  Bug#32082 : remove VOID macro
mysys/my_redel.c:
  Bug#32082 : remove VOID macro
mysys/stacktrace.c:
  Bug#32082 : remove VOID macro
mysys/thr_alarm.c:
  Bug#32082 : remove VOID macro
mysys/thr_lock.c:
  Bug#32082 : remove VOID macro
sql/derror.cc:
  Bug#32082 : remove VOID macro
sql/des_key_file.cc:
  Bug#32082 : remove VOID macro
sql/discover.cc:
  Bug#32082 : remove VOID macro
sql/field.cc:
  Bug#32082 : remove VOID macro
sql/filesort.cc:
  Bug#32082 : remove VOID macro
sql/ha_ndbcluster.cc:
  Bug#32082 : remove VOID macro
sql/ha_partition.cc:
  Bug#32082 : remove VOID macro
sql/handler.cc:
  Bug#32082 : remove VOID macro
sql/hostname.cc:
  Bug#32082 : remove VOID macro
sql/init.cc:
  Bug#32082 : remove VOID macro
sql/item.cc:
  Bug#32082 : remove VOID macro
sql/item_cmpfunc.cc:
  Bug#32082 : remove VOID macro
sql/item_strfunc.cc:
  Bug#32082 : remove VOID macro
sql/lock.cc:
  Bug#32082 : remove VOID macro
sql/log.cc:
  Bug#32082 : remove VOID macro
sql/log_event.cc:
  Bug#32082 : remove VOID macro
sql/mysqld.cc:
  Bug#32082 : remove VOID macro
sql/opt_range.h:
  Bug#32082 : remove VOID macro
sql/protocol.cc:
  Bug#32082 : remove VOID macro
sql/records.cc:
  Bug#32082 : remove VOID macro
sql/sp_head.cc:
  Bug#32082 : remove VOID macro
sql/sp_pcontext.cc:
  Bug#32082 : remove VOID macro
sql/sql_acl.cc:
  Bug#32082 : remove VOID macro
sql/sql_base.cc:
  Bug#32082 : remove VOID macro
sql/sql_cache.cc:
  Bug#32082 : remove VOID macro
sql/sql_connect.cc:
  Bug#32082 : remove VOID macro
sql/sql_db.cc:
  Bug#32082 : remove VOID macro
sql/sql_delete.cc:
  Bug#32082 : remove VOID macro
sql/sql_handler.cc:
  Bug#32082 : remove VOID macro
sql/sql_insert.cc:
  Bug#32082 : remove VOID macro
sql/sql_map.cc:
  Bug#32082 : remove VOID macro
sql/sql_parse.cc:
  Bug#32082 : remove VOID macro
sql/sql_select.cc:
  Bug#32082 : remove VOID macro
sql/sql_servers.cc:
  Bug#32082 : remove VOID macro
sql/sql_show.cc:
  Bug#32082 : remove VOID macro
sql/sql_string.cc:
  Bug#32082 : remove VOID macro
sql/sql_table.cc:
  Bug#32082 : remove VOID macro
sql/sql_test.cc:
  Bug#32082 : remove VOID macro
sql/sql_trigger.cc:
  Bug#32082 : remove VOID macro
sql/sql_update.cc:
  Bug#32082 : remove VOID macro
sql/sql_view.cc:
  Bug#32082 : remove VOID macro
sql/table.cc:
  Bug#32082 : remove VOID macro
sql/tztime.cc:
  Bug#32082 : remove VOID macro
sql/udf_example.c:
  Bug#32082 : remove VOID macro
sql/uniques.cc:
  Bug#32082 : remove VOID macro
sql/unireg.cc:
  Bug#32082 : remove VOID macro
storage/archive/ha_archive.cc:
  Bug#32082 : remove VOID macro
storage/blackhole/ha_blackhole.cc:
  Bug#32082 : remove VOID macro
storage/csv/ha_tina.cc:
  Bug#32082 : remove VOID macro
storage/csv/transparent_file.cc:
  Bug#32082 : remove VOID macro
storage/example/ha_example.cc:
  Bug#32082 : remove VOID macro
storage/federated/ha_federated.cc:
  Bug#32082 : remove VOID macro
storage/heap/hp_clear.c:
  Bug#32082 : remove VOID macro
storage/heap/hp_create.c:
  Bug#32082 : remove VOID macro
storage/heap/hp_test1.c:
  Bug#32082 : remove VOID macro
storage/heap/hp_test2.c:
  Bug#32082 : remove VOID macro
storage/innobase/handler/ha_innodb.cc:
  Bug#32082 : remove VOID macro
storage/myisam/ft_eval.c:
  Bug#32082 : remove VOID macro
storage/myisam/ha_myisam.cc:
  Bug#32082 : remove VOID macro
storage/myisam/mi_changed.c:
  Bug#32082 : remove VOID macro
storage/myisam/mi_check.c:
  Bug#32082 : remove VOID macro
storage/myisam/mi_close.c:
  Bug#32082 : remove VOID macro
storage/myisam/mi_create.c:
  Bug#32082 : remove VOID macro
storage/myisam/mi_dbug.c:
  Bug#32082 : remove VOID macro
storage/myisam/mi_delete.c:
  Bug#32082 : remove VOID macro
storage/myisam/mi_delete_all.c:
  Bug#32082 : remove VOID macro
storage/myisam/mi_dynrec.c:
  Bug#32082 : remove VOID macro
storage/myisam/mi_info.c:
  Bug#32082 : remove VOID macro
storage/myisam/mi_locking.c:
  Bug#32082 : remove VOID macro
storage/myisam/mi_log.c:
  Bug#32082 : remove VOID macro
storage/myisam/mi_open.c:
  Bug#32082 : remove VOID macro
storage/myisam/mi_packrec.c:
  Bug#32082 : remove VOID macro
storage/myisam/mi_panic.c:
  Bug#32082 : remove VOID macro
storage/myisam/mi_rsame.c:
  Bug#32082 : remove VOID macro
storage/myisam/mi_statrec.c:
  Bug#32082 : remove VOID macro
storage/myisam/mi_test1.c:
  Bug#32082 : remove VOID macro
storage/myisam/mi_test2.c:
  Bug#32082 : remove VOID macro
storage/myisam/mi_test3.c:
  Bug#32082 : remove VOID macro
storage/myisam/mi_update.c:
  Bug#32082 : remove VOID macro
storage/myisam/mi_write.c:
  Bug#32082 : remove VOID macro
storage/myisam/myisamchk.c:
  Bug#32082 : remove VOID macro
storage/myisam/myisamlog.c:
  Bug#32082 : remove VOID macro
storage/myisam/myisampack.c:
  Bug#32082 : remove VOID macro
storage/myisam/sort.c:
  Bug#32082 : remove VOID macro
storage/myisammrg/myrg_close.c:
  Bug#32082 : remove VOID macro
storage/myisammrg/myrg_create.c:
  Bug#32082 : remove VOID macro
storage/myisammrg/myrg_open.c:
  Bug#32082 : remove VOID macro
strings/str_test.c:
  Bug#32082 : remove VOID macro
tests/thread_test.c:
  Bug#32082 : remove VOID macro