This is a backport of code from MySQL 6.0 with cleanups and extensions

The following new options are supported
configure options:
  --with-libevent                  ; Enable use of libevent, which is needed for pool of threads

mysqld options:
--thread-handling=pool-of-threads  ; Use a pool of threads to handle queries
--thread-pool-size=#               ; Define how many threads should be created to handle all queries
--extra-port=#                     ; Extra tcp port that uses the old one-thread-per-connection method
--extra-max-connections=#          ; Number of connections to accept to 'extra-port'
--test-ignore-wrong-options        ; Ignore setting an enum value to a wrong option (for mysql-test-run)



BUILD/SETUP.sh:
  Added libevents (and thus pool-of-threads) to max builds
CMakeLists.txt:
  Added libevent
Makefile.am:
  Added libevents
config/ac-macros/libevent.m4:
  Libevent code for configure
config/ac-macros/libevent_configure.m4:
  Libevent code for configure
configure.in:
  Added libevents
dbug/dbug.c:
  Added _db_is_pushed(); Needed for pool-of-threads code
extra/Makefile.am:
  Added libevents
extra/libevent:
  Libevent initial code
extra/libevent/CMakeLists.txt:
  Libevent initial code
extra/libevent/Makefile.am:
  Libevent initial code
extra/libevent/README:
  Libevent initial code
extra/libevent/WIN32-Code:
  Libevent initial code
extra/libevent/WIN32-Code/config.h:
  Libevent initial code
extra/libevent/WIN32-Code/misc.c:
  Libevent initial code
extra/libevent/WIN32-Code/misc.h:
  Libevent initial code
extra/libevent/WIN32-Code/tree.h:
  Libevent initial code
extra/libevent/WIN32-Code/win32.c:
  Libevent initial code
extra/libevent/buffer.c:
  Libevent initial code
extra/libevent/compat:
  Libevent initial code
extra/libevent/compat/sys:
  Libevent initial code
extra/libevent/compat/sys/_time.h:
  Libevent initial code
extra/libevent/compat/sys/queue.h:
  Libevent initial code
extra/libevent/compat/sys/tree.h:
  Libevent initial code
extra/libevent/devpoll.c:
  Libevent initial code
extra/libevent/epoll.c:
  Libevent initial code
extra/libevent/epoll_sub.c:
  Libevent initial code
extra/libevent/evbuffer.c:
  Libevent initial code
extra/libevent/evdns.c:
  Libevent initial code
extra/libevent/evdns.h:
  Libevent initial code
extra/libevent/event-config.h:
  Libevent initial code
extra/libevent/event-internal.h:
  Libevent initial code
extra/libevent/event.c:
  Libevent initial code
extra/libevent/event.h:
  Libevent initial code
extra/libevent/event_tagging.c:
  Libevent initial code
extra/libevent/evhttp.h:
  Libevent initial code
extra/libevent/evport.c:
  Libevent initial code
extra/libevent/evrpc-internal.h:
  Libevent initial code
extra/libevent/evrpc.c:
  Libevent initial code
extra/libevent/evrpc.h:
  Libevent initial code
extra/libevent/evsignal.h:
  Libevent initial code
extra/libevent/evutil.c:
  Libevent initial code
extra/libevent/evutil.h:
  Libevent initial code
extra/libevent/http-internal.h:
  Libevent initial code
extra/libevent/http.c:
  Libevent initial code
extra/libevent/kqueue.c:
  Libevent initial code
extra/libevent/log.c:
  Libevent initial code
extra/libevent/log.h:
  Libevent initial code
extra/libevent/min_heap.h:
  Libevent initial code
extra/libevent/poll.c:
  Libevent initial code
extra/libevent/select.c:
  Libevent initial code
extra/libevent/signal.c:
  Libevent initial code
extra/libevent/strlcpy-internal.h:
  Libevent initial code
extra/libevent/strlcpy.c:
  Libevent initial code
include/config-win.h:
  Libevent support
include/my_dbug.h:
  ADded _db_is_pushed
include/mysql.h.pp:
  Update to handle new prototypes
include/typelib.h:
  Split find_type_or_exit() into two functions
include/violite.h:
  Added vio_is_pending()
libmysqld/Makefile.am:
  Added libevent
mysql-test/include/have_pool_of_threads.inc:
  Added test for pool-of-threads
mysql-test/mysql-test-run.pl:
  Don't abort based on time and don't retry test cases when run under --gdb or --debug
mysql-test/r/crash_commit_before.result:
  USE GLOBAL for debug variable
mysql-test/r/have_pool_of_threads.require:
  Added test for pool-of-threads
mysql-test/r/pool_of_threads.result:
  Added test for pool-of-threads
mysql-test/r/subselect_debug.result:
  USE GLOBAL for debug variable
mysql-test/t/crash_commit_before.test:
  USE GLOBAL for debug variable
mysql-test/t/merge-big.test:
  USE GLOBAL for debug variable
mysql-test/t/pool_of_threads-master.opt:
  Added test for pool-of-threads
mysql-test/t/pool_of_threads.test:
  Added test for pool-of-threads
mysys/typelib.c:
  Split find_type_or_exit() into find_type_with_warning()
sql/Makefile.am:
  Added libevent
sql/handler.cc:
  Indentation fix.
  Fixed memory loss bug
  Fixed crash on exit when handler plugin failed
sql/mysql_priv.h:
  Added extra_max_connections and mysqld_extra_port
  Added extern functions from sql_connect.cc
sql/mysqld.cc:
  Added support for new mysqld options
  Added code for 'extra-port' and 'extra-max-connections'
  Split some functions into smaller pieces to be able to reuse code
  Added code for test-ignore-wrong-options
sql/scheduler.cc:
  Updated schduler code from MySQL 6.0
sql/scheduler.h:
  Updated schduler code from MySQL 6.0
sql/set_var.cc:
  Added support for changing "extra_max_connections"
sql/sql_class.cc:
  Iniitalize thread schduler options in THD
sql/sql_class.h:
  Added to extra_port and scheduler to 'THD'
sql/sql_connect.cc:
  Use thd->schduler to check number of connections and terminate connection
  Made some local functions global (for scheduler.cc)
vio/viosocket.c:
  Added 'vio_pending', needed for scheduler..c

- added a summary section at the bottom of the configure output

mysql-test/t/variables.test:
  Reset delay_key_write, otherwise maria.maria test may fail
sql/set_var.cc:
  Reset ha_open_options if one resets the delay_key_write variable.
  Before there was no way to reset it without restarting mysqld, which caused some tests to fail

Contains fixes for test cases
Changed release tag to beta

configure.in:
  change release tag to beta

- adding back Serg's "mtr --list-options"
- safe_mutex deadlock detector started raising wrong deadlock warnings, fixed
here by a backport from 6.0-main.

include/my_pthread.h:
  Porting changes done to 6.0-main which satisfy the safe_mutex deadlock detector (those
  in 5.1-main don't), see chad@mysql.com-20090126155607-n0j3zbmgbfepnmmo for explanations
mysql-test/mysql-test-run.pl:
  adding back Serg's --list-options
mysys/my_init.c:
  Porting changes done to 6.0-main which satisfy the safe_mutex deadlock detector (those
  in 5.1-main don't), see chad@mysql.com-20090126155607-n0j3zbmgbfepnmmo for explanations
mysys/my_thr_init.c:
  Porting changes done to 6.0-main which satisfy the safe_mutex deadlock detector (those
  in 5.1-main don't), see chad@mysql.com-20090126155607-n0j3zbmgbfepnmmo for explanations

There were so many changes into mtr (this is the new mtr coming) that I rather
copied mtr from 6.0-main here (at least this one knows how to run Maria tests).
I also fixed suite/maria tests to be accepted by the new mtr.

mysys/thr_mutex.c:
  adding DBUG_PRINT here, so that we can locate where the warning is issued.

it was bug in a test program, changed WT_THD's initialization to ensure they have no garbage from the previous run.

Assert that keys don't point to bitmap pages.

storage/maria/ma_blockrec.h:
  assertion
storage/maria/ma_locking.c:
  With concurrent INSERTs, it is possible that two threads enter _ma_mark_file_changed()
  at the same time, so they should serialize their access to the "changed" state/share
  members; another reason is that this function may call _ma_update_state_lsns_sub()
  which may call translog_deassign_id_from_share() (I saw it during testing of
  online backup) which requires the intern_lock mutex.
  As INSERTs only change from "not changed" to "changed", we can first check without mutex:
  if it says "changed", some other thread has set or is setting the variables now,
  we don't need to do it; if it says "not changed", we serialize and re-check.

storage/maria/ha_maria.cc:
  comment
storage/maria/ma_checkpoint.c:
  comment
storage/maria/ma_extra.c:
  use bitmap mutex when changing bitmap.changed, sounds safer
storage/maria/ma_pagecache.c:
  comment
storage/maria/ma_recovery.c:
  comments

don't treat deadlock or timeout as a sign of corruption

The original symptoms of this bug have been fixed as a consequence of other bug fixes.
Taking this time to correct some formatting, such as replacing error numbers with names.
Beginning this with 5.0

The patch adds restart of mysql server and replacing of binlog file 
when mysql server is stopped.

There are two issues: 
      1. 6.0 uses the obsolate master-*** server options;
      2. the test is not deterministic in that although master vs slave consistency is
         fine, two runs of the test can have different results. The reason of the
         non-determinism is the combination of 
         a chosen way to demo results and the ndb_autoincrement_prefetch_sz feature.

The current patch fixes the 2nd issue by putting out results via diff_table macro
instead of the former run-sensitive method.
The 1st issue is going to be fixed by a separate patch to 6.0.

mysql-test/suite/rpl_ndb/r/rpl_ndb_circular_2ch.result:
  results changed
mysql-test/suite/rpl_ndb/t/rpl_ndb_circular_2ch.test:
  Test is refined to put out results via diff_table macro instead of the former run-sensitive
  method.

Problem:
Custom UCA collations didn't set the MY_CS_STRNXFRM flag,
which resulted in "prefix_search" method instead of
the required "seq_search".

Problem2: (not metioned in the bug report)
Custom UCA collations didn't also set the MY_CS_UNICODE flag,
so an attempt to compare a column with a custom UCA collation
to another column with a non-Unicode character set led to
the "illegal mix of collation" error.

Fix:
the two missing flags was added into collation initialization.

  Upgrade:

  - All fulltext indexes with custom UCA collations should be rebuilt.

  - Non-fulltext custom UCA indexes should likely be rebuild as well.

Remove size of binlog file from SHOW BINARY LOGS. 
Changing size of binlog file is an affect of adding or removing events to/from
binlog and it can be checked in next command of test: SHOW BINLOG EVENTS.
For SHOW BINARY LOGS statement enough to show the list of file names.

fixed federated warnings

mysql-test/suite/jp/r/jp_create_db_sjis.result:
  hide mtr database
mysql-test/suite/jp/r/jp_create_db_ucs2.result:
  hide mtr database
mysql-test/suite/jp/r/jp_create_db_ujis.result:
  hide mtr database
mysql-test/suite/jp/r/jp_create_db_utf8.result:
  hide mtr database
mysql-test/suite/jp/t/jp_create_db_sjis.test:
  hide mtr database
mysql-test/suite/jp/t/jp_create_db_ucs2.test:
  hide mtr database
mysql-test/suite/jp/t/jp_create_db_ujis.test:
  hide mtr database
mysql-test/suite/jp/t/jp_create_db_utf8.test:
  hide mtr database