corruption errors: 126,134,145

When one thread attempts to lock two (or more) tables and another
thread executes statement that aborts these locks (e.g. REPAIR
TABLE) we may get a table object with wrong lock type in a table
cache.

For example if SELECT FROM t1,t2 was aborted, subsequent INSERT
INTO t1 may be executed under read lock.

As a result we may get various table corruptions and even a server
crash.

This is fixed by resetting lock type in case lock was aborted by
another thread.

I failed to create reasonable test case for this bug.

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

into  whalegate.ndb.mysql.com:/home/tomas/mysql-4.1-ndb

into  quadxeon.mysql.com:/benchmarks/ext3/TOSAVE/tsmith/bk/maint/41

into  whalegate.ndb.mysql.com:/home/tomas/mysql-4.1-ndb

into  mysql.com:/d2/hf/mrg/mysql-4.1-opt

into  pilot.blaudden:/home/msvensson/mysql/mysql-4.1-maint

 - Final touchups

into  perch.ndb.mysql.com:/home/jonas/src/mysql-4.1-ndb

  review comment 2, atleast 1 signal need for test prg

into  perch.ndb.mysql.com:/home/jonas/src/mysql-4.1-ndb

  review comment
  if some tcp-transporter has data, then do select with timeout 0

into  perch.ndb.mysql.com:/home/jonas/src/mysql-4.1-ndb

  Make sure that data can not e left lingering in receive buffer

into  siva.hindu.god:/home/tsmith/m/bk/maint/41

BUG#25712 - insert delayed and check table run together report crashed
            tables
Fixed wrongly applied patch.

BUG#25712 - insert delayed and check table run together report
            crashed tables

Let MY_THREADSAFE have distinct value. Some functions call my_seek
passing MyFlags argument directly to it. This may cause unnecessary
locks, which may finally lead to a dead-lock (specifically see my_lock).

            tables

In case system doesn't have native pread/pwrite calls (e.g. Windows)
and there is CHECK TABLE runs concurrently with another statement that
reads from a table, the table may be reported as crashed.

This is fixed by locking file descriptor when my_seek is executed on
MyISAM index file and emulated pread/pwrite may be executed concurrently.

Affects MyISAM tables on platforms that do not have native
pread/pwrite calls (e.g. Windows).

No deterministic test case for this bug.

 - Fix spelling error

into  pippilotta.erinye.com:/shared/home/df/mysql/build/mysql-4.1-build

 - Change from "query_sorted <query>" to "sorted_results"

into  vajra.(none):/opt/local/work/mysql-4.1-runtime

for a query over an empty table right after its creation. 
The crash is the result of an attempt made by JOIN::optimize to evaluate
the WHERE condition when no records have been actually read.
The added test case can reproduce the crash only with InnoDB tables and
only with 5.0.x.
 

statement from a UNION query with ORDER BY an expression containing
RAND().
The crash happened because the global order by list in the union query
was not re-initialized for execution.
(Local order by lists were re-initialized though).

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

- Give some more protection against "too long socket name by setting the max
length when to use a tmpdir for sockets to 70 

into  whalegate.ndb.mysql.com:/home/tomas/mysql-4.1-ndb

into  pilot.blaudden:/home/msvensson/mysql/mysql-4.1-maint

 - Change "exec rm" to "remove_file"

into  pilot.blaudden:/home/msvensson/mysql/mysql-4.1-maint

 - Queries in the query cache are identified by the individual 
   characters in the query statement, the current database and 
   the current environment expressed as a set of system variable
   flags.
 - Since the set of environment flags didn't properly describe the
   current environment unexpected results were returned from the 
   query cache.
 - Query cache is now cleared when the variable ft_boolean_syntax is 
   updated.
 - An identification flag for the variable default_week_format is 
   added to the query cache record.
 
Thanks to Martin Friebe who has supplied significant parts of this patch.

into  dev3-221.dev.cn.tlan:/home/ngb/mysql/mysql-4.1/mysql-4.1-ndb

into  zippy.cornsilk.net:/home/cmiller/work/mysql/mysql-4.1-maint

into  mysql.com:/d2/hf/mrg/mysql-4.1-opt

The message is gramatically wrong, and factually wrong.

Change it to refer to the myisam_sort_buffer_size variable and change
"to" to "too".

Warnings may show up in the error log that complain about a table, yet
don't tell us which table.

Add the database and table names to the message.

When checking for applicability of join cache
we must disable its usage only if there is no
temp table in use.
When a temp table is used we can use join
cache (and it will not make the result-set 
unordered) to fill the temp table. The filesort() 
operation is then applied to the data in the temp 
table and hence is not affected by join cache
usage.
Fixed by narrowing the condition for disabling 
join cache to exclude the case where temp table
is used.

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

The generic string to int conversion was used by the Item_func_signed and
the Item_func_unsigned classes to convert DATE/DATETIME values to the
SIGNED/UNSIGNED type. But this conversion produces wrong results for such
values.

Now if the item which result has to be converted can return its result as
longlong then the item->val_int() method is used to allow the item to carry
out the conversion itself and return the correct result.
This condition is checked in the Item_func_signed::val_int() and the
Item_func_unsigned::val_int() functions.