The patch for Bug 26379 (Combination of FLUSH TABLE and
REPAIR TABLE corrupts a MERGE table) fixed this bug too.
However it revealed a new bug that crashed the server.

Flushing a merge table at the moment when it is between open
and attach of children crashed the server.

The flushing thread wants to abort locks on the flushed table.
It calls ha_myisammrg::lock_count() and ha_myisammrg::store_lock()
on the TABLE object of the other thread.

Changed ha_myisammrg::lock_count() and ha_myisammrg::store_lock()
to accept non-attached children. ha_myisammrg::lock_count() returns
the number of MyISAM tables in the MERGE table so that the memory
allocation done by get_lock_data() is done correctly, even if the
children become attached before ha_myisammrg::store_lock() is
called. ha_myisammrg::store_lock() will not return any lock if the
children are not attached.

This is however a change in the handler interface. lock_count()
can now return a higher number than store_lock() stores locks.
This is more safe than the reverse implementation would be.
get_lock_data() in the SQL layer is adjusted accordingly. It sets
MYSQL_LOCK::lock_count based on the number of locks returned by
the handler::store_lock() calls, not based on the numbers returned
by the handler::lock_count() calls. The latter are only used for
allocation of memory now.

No test case. The test suite cannot reliably run FLUSH between
lock_count() and store_lock() of another thread. The bug report
contains a program that can repeat the problem with some
probability.


include/myisammrg.h:
  Bug#30273 - merge tables: Can't lock file (errno: 155)
  Added mutex to struct st_myrg_info (MYRG_INFO).
sql/handler.h:
  Bug#30273 - merge tables: Can't lock file (errno: 155)
  Extended comments for handler::lock_count() and
  handler::store_lock().
sql/lock.cc:
  Bug#30273 - merge tables: Can't lock file (errno: 155)
  Changed get_lock_data() so that the final lock_count is taken
  from the number of locks returned from handler::store_lock()
  instead of from handler::lock_count().
sql/sql_base.cc:
  Fixed a purecov comment. (unrelated to the rest of the changeset)
storage/myisammrg/ha_myisammrg.cc:
  Bug#30273 - merge tables: Can't lock file (errno: 155)
  Changed ha_myisammrg::lock_count() and ha_myisammrg::store_lock()
  to accept non-attached children.
  Protected ha_myisammrg::store_lock() by MYRG_INFO::mutex.
storage/myisammrg/myrg_close.c:
  Bug#30273 - merge tables: Can't lock file (errno: 155)
  Added MYRG_INFO::mutex destruction to myrg_parent_close().
storage/myisammrg/myrg_open.c:
  Bug#30273 - merge tables: Can't lock file (errno: 155)
  Added MYRG_INFO::mutex initialization to myrg_parent_open().
  Protected myrg_attach_children() and myrg_detach_children()
  by MYRG_INFO::mutex.
  Fixed a purecov comment. (unrelated to the rest of the changeset)

            with error 1005.

CSV doesn't support nullable fields. Report descriptive error if create
table with nullable field is requested.


mysql-test/r/csv.result:
  A test case for BUG#32817.
mysql-test/t/csv.test:
  A test case for BUG#32817.
storage/csv/ha_tina.cc:
  CSV doesn't support nullable fields. Report descriptive error if create
  table with nullable field is requested.

into  witty.:/Users/mattiasj/clones/51to_push


sql/ha_partition.cc:
  Auto merged
sql/sql_partition.cc:
  Auto merged

(also fixes the bugs: Bug#29320, Bug#29493 and Bug#30536)

Problem: Partitioning did not handle unordered scans correctly
for engines with unordered read order.

Solution: do not stop scanning fi a recored is out of range, since
there can be more records within the range afterwards.

Note: this is the patch that fixes the bug, but since there are no
storage engines shipped with mysql 5.1 (falcon comes in 6.0) there
are no test cases (it is a separate patch that only goes into 6.0)


sql/ha_partition.cc:
  Bug#30480: Falcon: searches fail if LIKE and key partition
  
  Problem was that partitioning did not handle unordered scans correctly
  for engines with unordered read order.
  
  Solution: do not stop if a recored is out of range, since it can come
  more records within the range afterwards

into  stella.local:/home2/mydev/mysql-5.1-axmrg

into  stella.local:/home2/mydev/mysql-5.1-axmrg

into  stella.local:/home2/mydev/mysql-5.1-bug30491

1. A bad error message was given when a MERGE table with an
   InnoDB child table was tried to use.

2. After selecting from a correct MERGE table and then altering
   one of the children to InnoDB, incorrect results were returned.

These bugs have been fixed with the patch for bug 26379 (Combination
of FLUSH TABLE and REPAIR TABLE corrupts a MERGE table).

For verification, I added the test case from the bug report.


mysql-test/r/merge_innodb.result:
  Bug#30491 - MERGE doesn't report error when one table is Innodb
  Added test result.
mysql-test/t/merge_innodb.test:
  Bug#30491 - MERGE doesn't report error when one table is Innodb
  Added test case.

Reverted log tables alteration.


scripts/mysql_system_tables_fix.sql:
  Altering log table is wrong, because
  - it is not possible to alter log table when it is in use;
  - log table may use MyISAM engine, which perfectly supports NULLs.
  
  Reverted log tables alteration.

into  mysql.com:/home/ram/work/b29258/b29258.5.1


mysql-test/r/partition.result:
  Manually merged
mysql-test/t/partition.test:
  Manually merged

into  april.(none):/home/svoj/devel/mysql/BUG32050/mysql-5.1-engines

into  stella.local:/home2/mydev/mysql-5.1-axmrg


mysql-test/r/ctype_euckr.result:
  Auto merged
mysql-test/r/ctype_uca.result:
  Auto merged

into  stella.local:/home2/mydev/mysql-5.1-axmrg

  - result adjusted.

into  mysql.com:/home/svoj/devel/mysql/BUG31833/mysql-5.1-engines


mysql-test/r/archive.result:
  Auto merged
mysql-test/t/archive.test:
  Auto merged

into  mysql.com:/home/ram/work/b32726/b32726.5.0


mysql-test/r/ctype_euckr.result:
  Auto merged
mysql-test/r/ctype_uca.result:
  Auto merged

into  mysql.com:/home/ram/work/b32726/b32726.5.1


mysql-test/r/ctype_euckr.result:
  Auto merged
mysql-test/r/ctype_uca.result:
  Auto merged
strings/ctype-cp932.c:
  Auto merged
mysql-test/extra/binlog_tests/ctype_cp932.test:
  Auto merged
mysql-test/suite/binlog/r/binlog_stm_ctype_cp932.result:
  Auto merged

into  stella.local:/home2/mydev/mysql-5.1-axmrg


mysql-test/r/delayed.result:
  Auto merged
mysql-test/t/delayed.test:
  Auto merged
sql/sql_insert.cc:
  Auto merged

into  mysql.com:/home/ram/work/b32559/b32559.5.0

into  mysql.com:/home/ram/work/b32559/b32559.5.1


mysql-test/r/func_misc.result:
  Auto merged
sql/item.cc:
  Auto merged
sql/item.h:
  Auto merged
mysql-test/t/func_misc.test:
  manual merge.

into  mysql.com:/home/ram/work/b32676/b32676.5.1

into  mysql.com:/home/ram/work/b32676/b32676.5.0


mysql-test/r/delayed.result:
  Auto merged
mysql-test/t/delayed.test:
  Auto merged
sql/sql_insert.cc:
  Auto merged

into  stella.local:/home2/mydev/mysql-5.1-axmrg


mysql-test/t/disabled.def:
  Manual merge from 5.0.

Moved disabling to rpl suite.
Bug#32801 wait_timeout.test fails randomly
Disabled test case.


mysql-test/suite/rpl/t/disabled.def:
  Bug#8693 Test 'rpl_log_pos' fails sometimes
  Moved disabling to rpl suite.

into  mysql.com:/home/ram/work/b32676/b32676.5.1


sql/sql_insert.cc:
  Auto merged
mysql-test/r/delayed.result:
  manual merge.
mysql-test/t/delayed.test:
  manual merge.

Disabled test case.

  - fix for #31070 (missed during merging) applied for cp932 charset.
  - tests/results adjusted.


mysql-test/include/ctype_common.inc:
  Fix for bug #32726: crash with cast in order by clause and cp932 charset
    - tests/results adjusted.
mysql-test/r/ctype_big5.result:
  Fix for bug #32726: crash with cast in order by clause and cp932 charset
    - tests/results adjusted.
mysql-test/r/ctype_cp932.result:
  Fix for bug #32726: crash with cast in order by clause and cp932 charset
    - tests/results adjusted.
mysql-test/r/ctype_euckr.result:
  Fix for bug #32726: crash with cast in order by clause and cp932 charset
    - tests/results adjusted.
mysql-test/r/ctype_gb2312.result:
  Fix for bug #32726: crash with cast in order by clause and cp932 charset
    - tests/results adjusted.
mysql-test/r/ctype_gbk.result:
  Fix for bug #32726: crash with cast in order by clause and cp932 charset
    - tests/results adjusted.
mysql-test/r/ctype_uca.result:
  Fix for bug #32726: crash with cast in order by clause and cp932 charset
    - tests/results adjusted.
mysql-test/t/ctype_cp932.test:
  Fix for bug #32726: crash with cast in order by clause and cp932 charset
    - tests/results adjusted.
strings/ctype-cp932.c:
  Fix for bug #32726: crash with cast in order by clause and cp932 charset
    - fix for #31070 (missed during merging) applied for cp932.

into  stella.local:/home2/mydev/mysql-5.1-axmrg


client/mysql.cc:
  Auto merged
mysql-test/r/archive.result:
  Auto merged
mysql-test/r/ctype_ucs.result:
  Auto merged
mysql-test/t/archive.test:
  Auto merged
mysql-test/t/ctype_uca.test:
  Auto merged
mysql-test/t/ctype_ucs.test:
  Auto merged
sql/item_cmpfunc.cc:
  Auto merged
sql/mysqld.cc:
  Auto merged
sql/sql_class.h:
  Auto merged
mysql-test/t/disabled.def:
  Manual merge from 5.0
mysql-test/t/subselect.test:
  Manual merge from 5.0

into  stella.local:/home2/mydev/mysql-5.1-axmrg


include/my_base.h:
  Auto merged
mysql-test/mysql-test-run.pl:
  Auto merged
mysql-test/suite/ndb/t/disabled.def:
  Auto merged
mysql-test/t/partition.test:
  Auto merged
sql/handler.cc:
  Auto merged
sql/item_cmpfunc.cc:
  Auto merged
sql/slave.cc:
  Auto merged
sql/sql_insert.cc:
  Auto merged
sql/sql_parse.cc:
  Auto merged
sql/sql_select.cc:
  Auto merged
sql/sql_table.cc:
  Auto merged
sql/sql_yacc.yy:
  Auto merged
client/mysql.cc:
  Manual merge
mysql-test/suite/rpl/t/disabled.def:
  Manual merge

into  stella.local:/home2/mydev/mysql-5.0-axmrg

into  stella.local:/home2/mydev/mysql-5.0-axmrg

Disabled the test case.

into  mysql.com:/home/ram/work/b30495/b30495.5.0

into  mysql.com:/home/ram/work/b30495/b30495.5.1

into  stella.local:/home2/mydev/mysql-5.0-axmrg


sql/item_cmpfunc.cc:
  Auto merged

into  mysql.com:/home/ram/work/b30495/b30495.5.0

mysql-test/suite/ndb/t/disabled.def:
  Disabling failing tests.
mysql-test/suite/rpl/t/disabled.def:
  Disabling failing tests.
mysql-test/suite/rpl/t/rpl_ssl.test:
  Disabling part of test that fails.

INSERT/UPDATE against CSV table created by MySQL earlier than 5.1.23
with NULL-able column results in server crash in debug builds.

Starting with 5.1.23 CSV doesn't permit creation of NULL-able columns,
but it is still possible to get such table from older MySQL versions.

Fixed by removing excessive DBUG_ASSERT().


scripts/mysql_system_tables_fix.sql:
  Starting with 5.1.23 CSV doesn't permit creation of NULL-able columns.
  Alter system CSV tables structure so that all columns are NOT NULL.
storage/csv/ha_tina.cc:
  Starting with 5.1.23 CSV doesn't permit creation of NULL-able columns,
  but it is still possible to get such table from older MySQL versions.
  
  Removed excessive DBUG_ASSERT().

  - archive test/result adjusted.
  - OPTIMIZE/ANALYZE PARTITION EXTENDED test case added.


mysql-test/r/archive.result:
  after-merge fix:
    - archive test/result adjusted.
mysql-test/r/partition.result:
  after-merge fix:
    - test case added.
mysql-test/t/archive.test:
  after-merge fix:
    - archive test/result adjusted.
mysql-test/t/partition.test:
  after-merge fix:
    - test case added.