Bug 18914 (Calling certain SPs from triggers fail)
Bug 20713 (Functions will not not continue for SQLSTATE VALUE '42S02')
Bug 21825 (Incorrect message error deleting records in a table with a
  trigger for inserting)
Bug 22580 (DROP TABLE in nested stored procedure causes strange dependency
  error)
Bug 25345 (Cursors from Functions)


This fix resolves a long standing issue originally reported with bug 8407,
which affect the behavior of Stored Procedures, Stored Functions and Trigger
in many different ways, causing symptoms reported by all the bugs listed.
In all cases, the root cause of the problem traces back to 8407 and how the
server locks tables involved with sub statements.

Prior to this fix, the implementation of stored routines would:
- compute the transitive closure of all the tables referenced by a top level
statement
- open and lock all the tables involved
- execute the top level statement
"transitive closure of tables" means collecting:
- all the tables,
- all the stored functions,
- all the views,
- all the table triggers
- all the stored procedures
involved, and recursively inspect these objects definition to find more
references to more objects, until the list of every object referenced does
not grow any more.
This mechanism is known as "pre-locking" tables before execution.
The motivation for locking all the tables (possibly) used at once is to
prevent dead locks.

One problem with this approach is that, if the execution path the code
really takes during runtime does not use a given table, and if the table is
missing, the server would not execute the statement.
This in particular has a major impact on triggers, since a missing table
referenced by an update/delete trigger would prevent an insert trigger to run.

Another problem is that stored routines might define SQL exception handlers
to deal with missing tables, but the server implementation would never give
user code a chance to execute this logic, since the routine is never
executed when a missing table cause the pre-locking code to fail.

With this fix, the internal implementation of the pre-locking code has been
relaxed of some constraints, so that failure to open a table does not
necessarily prevent execution of a stored routine.

In particular, the pre-locking mechanism is now behaving as follows:

1) the first step, to compute the transitive closure of all the tables
possibly referenced by a statement, is unchanged.

2) the next step, which is to open all the tables involved, only attempts
to open the tables added by the pre-locking code, but silently fails without
reporting any error or invoking any exception handler is the table is not
present. This is achieved by trapping internal errors with
Prelock_error_handler

3) the locking step only locks tables that were successfully opened.

4) when executing sub statements, the list of tables used by each statements
is evaluated as before. The tables needed by the sub statement are expected
to be already opened and locked. Statement referencing tables that were not
opened in step 2) will fail to find the table in the open list, and only at
this point will execution of the user code fail.

5) when a runtime exception is raised at 4), the instruction continuation
destination (the next instruction to execute in case of SQL continue
handlers) is evaluated.
This is achieved with sp_instr::exec_open_and_lock_tables()

6) if a user exception handler is present in the stored routine, that
handler is invoked as usual, so that ER_NO_SUCH_TABLE exceptions can be
trapped by stored routines. If no handler exists, then the runtime execution
will fail as expected.

With all these changes, a side effect is that view security is impacted, in
two different ways.

First, a view defined as "select stored_function()", where the stored
function references a table that may not exist, is considered valid.
The rationale is that, because the stored function might trap exceptions
during execution and still return a valid result, there is no way to decide
when the view is created if a missing table really cause the view to be invalid.

Secondly, testing for existence of tables is now done later during
execution. View security, which consist of trapping errors and return a
generic ER_VIEW_INVALID (to prevent disclosing information) was only
implemented at very specific phases covering *opening* tables, but not
covering the runtime execution. Because of this existing limitation,
errors that were previously trapped and converted into ER_VIEW_INVALID are
not trapped, causing table names to be reported to the user.
This change is exposing an existing problem, which is independent and will
be resolved separately.

into  moonlight.home:/home/tomash/src/mysql_ab/mysql-5.0-bug23527

           high load

MySQL server could crash if two or more threads would initiate query
cache resize at the moments very close in time.

The problem was introduced with the fix of bug 21051 in 5.0 and 5.1:
simultaneous query cache resizes would wait for the first one in
progress, but then each thread would try to finish the operation,
accessing the data that was already reset (attempt to dereference
'bins' pointer, which may be NULL already).

The solution is to check after synchronization if another thread has
done the reset already (test 'query_cache_size > 0' again).

No test case is provided because the bug is a subject to a race.

into  mockturtle.local:/home/dlenev/src/mysql-5.0-merge

into  mysql.com:/home/svoj/devel/mysql/merge/mysql-5.0-engines

into  mysql.com:/home/svoj/devel/mysql/merge/mysql-5.0-engines

the team tree for additional investigation.

into  mockturtle.local:/home/dlenev/src/mysql-5.0-merge

into  chilla.local:/home/mydev/mysql-5.0-bug24607

After merge fix

into  chilla.local:/home/mydev/mysql-5.0-bug24607

Fixed test. On 32-bit machines which compile without
-DBIG_TABLES, MAX_ROWS is truncated to a 32-bit value.
Using a value below 4G is portable.

into  kahlann.erinye.com:/home/df/mysql/build/mysql-5.0-build-work

into  mysql.com:/home/svoj/devel/mysql/BUG24401/mysql-5.0-engines

into  mysql.com:/home/svoj/devel/mysql/BUG24401/mysql-5.0-engines

into  mysql.com:/home/svoj/devel/mysql/BUG24401/mysql-4.1-engines

into  willster.(none):/home/stewart/Documents/MySQL/5.0/ndb-work

into  poseidon.mysql.com:/home/tomas/mysql-5.0-ndb

into  chilla.local:/home/mydev/mysql-4.1-bug24607

into  chilla.local:/home/mydev/mysql-5.0-bug24607

into  clam.ndb.mysql.com:/export/space/pekka/ndb/version/my50-ndb

into  willster.(none):/home/stewart/Documents/MySQL/5.0/bug25487

into  mockturtle.local:/home/dlenev/src/mysql-5.0-bg24491

into  mysql.com:/home/svoj/devel/mysql/BUG24401/mysql-5.0-engines

on duplicate key".

INSERT ... SELECT ... ON DUPLICATE KEY UPDATE which was used in
stored routine or as prepared statement and which in its ON DUPLICATE
KEY clause erroneously tried to assign value to a column mentioned only
in its SELECT part was properly emitting error on the first execution
but succeeded on the second and following executions.

Code which is responsible for name resolution of fields mentioned in
UPDATE clause (e.g. see select_insert::prepare()) modifies table list
and Name_resolution_context used in this process. It uses
Name_resolution_context_state::save_state/restore_state() to revert
these modifications. Unfortunately those two methods failed to revert
properly modifications to TABLE_LIST::next_name_resolution_table
and this broke name resolution process for successive executions.

This patch fixes Name_resolution_context_state::save_state/restore_state()
in such way that it properly handles TABLE_LIST::next_name_resolution_table.

  
  aim is to:
  a) if set_connect_timeout called, timeout connect attempt (for retry on
  next call) after timeout period
  b) preserve existing blocking behaviour otherwise (for, e.g. mgmapi)
  
  Related to customer issue with long time deleting ndb_cluster_connection
  object. believe we're hanging on the connect(2) call until timeout (when
  we then realise we should exit the thread).

    Fix bug in event handling wrt early node shutdown

- post review changes

into  kahlann.erinye.com:/home/df/mysql/build/mysql-5.0-build

- make sure keys are copied correctly when varchar has 2 length bytes
- test case

Do not propagate this change into main trees.

into  kahlann.erinye.com:/home/df/mysql/build/mysql-5.0-build-work

into  kahlann.erinye.com:/home/df/mysql/build/mysql-5.0-build-work

into  kahlann.erinye.com:/home/df/mysql/build/mysql-5.0-build-work

into  kahlann.erinye.com:/home/df/mysql/build/mysql-4.1-build-work