Extending varchar column length with ALTER TABLE may result in unusable
memory table.

The problem is that we use fast ALTER TABLE in this case, which is not
supported by now.

This is fixed by refusing fast ALTER TABLE when extending varchar column.
In other words force copy of a table during ALTER TABLE.

Affects MEMORY tables in 5.1 only.


mysql-test/r/heap.result:
  A test case for BUG#26080.
mysql-test/t/heap.test:
  A test case for BUG#26080.
storage/heap/ha_heap.cc:
  For MEMORY, if varchar column extended, it should return incompatible for
  now. In other words force copy of a table during alter table.

into  chilla.local:/home/mydev/mysql-5.1-bug25460

Decreased code duplication by calling memory mapping
function through mi_extra().

into  chilla.local:/home/mydev/mysql-5.1-axmrg


mysys/my_thr_init.c:
  Auto merged

into  chilla.local:/home/mydev/mysql-5.1-axmrg


sql/mysql_priv.h:
  Auto merged

into  chilla.local:/home/mydev/mysql-5.1-axmrg

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

into  trift2.:/MySQL/M51/push-5.1

into  zippy.cornsilk.net:/home/cmiller/work/mysql/mysql-5.1-maint


sql/mysql_priv.h:
  Auto merged

into  zippy.cornsilk.net:/home/cmiller/work/mysql/mysql-5.0-maint


sql/mysql_priv.h:
  Auto merged

into  chilla.local:/home/mydev/mysql-5.1-axmrg


mysys/my_pthread.c:
  Auto merged
sql/item.cc:
  Auto merged
sql/item_cmpfunc.cc:
  Auto merged
sql/item_cmpfunc.h:
  Auto merged
sql/sql_select.cc:
  Auto merged

into  chilla.local:/home/mydev/mysql-5.1-axmrg


mysys/my_pthread.c:
  Auto merged

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


sql/item.cc:
  Auto merged
sql/item_cmpfunc.cc:
  Auto merged
sql/item_cmpfunc.h:
  Auto merged
sql/sql_select.cc:
  Auto merged

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


mysys/my_pthread.c:
  SCCS merged

into  olga.mysql.com:/home/igor/mysql-5.1-opt


BitKeeper/etc/gone:
  auto-union
mysql-test/r/select.result:
  Auto merged
mysql-test/t/select.test:
  Auto merged
mysys/my_getopt.c:
  Auto merged
sql/field.h:
  Auto merged
sql/item.cc:
  Auto merged
sql/item_cmpfunc.cc:
  Auto merged
sql/item_cmpfunc.h:
  Auto merged
sql/mysql_priv.h:
  Auto merged
sql/sql_prepare.cc:
  Auto merged
sql/sql_select.cc:
  Auto merged
sql/table.cc:
  Auto merged

into  olga.mysql.com:/home/igor/mysql-5.1-opt


BitKeeper/etc/gone:
  auto-union
mysys/my_getopt.c:
  Auto merged
sql/field.h:
  Auto merged
sql/item.cc:
  Auto merged
sql/item_cmpfunc.cc:
  Auto merged
sql/item_cmpfunc.h:
  Auto merged
sql/mysql_priv.h:
  Auto merged
sql/sql_prepare.cc:
  Auto merged
sql/sql_select.cc:
  Auto merged
sql/table.cc:
  Auto merged
mysql-test/r/select.result:
  SCCS merged
mysql-test/t/select.test:
  SCCS merged

into  bk-internal.mysql.com:/data0/bk/mysql-5.1-opt


sql/item.cc:
  Auto merged

into  zippy.cornsilk.net:/home/cmiller/work/mysql/mysql-5.1-maint

into  bk-internal.mysql.com:/data0/bk/mysql-5.0-opt


BitKeeper/etc/gone:
  auto-union
mysys/my_getopt.c:
  Auto merged
sql/field.h:
  Auto merged
sql/item.cc:
  Auto merged
sql/item_cmpfunc.cc:
  Auto merged
sql/item_cmpfunc.h:
  Auto merged
sql/mysql_priv.h:
  Auto merged
sql/sql_prepare.cc:
  Auto merged
sql/sql_select.cc:
  Auto merged
sql/table.cc:
  Auto merged
mysql-test/r/select.result:
  Manual merge
mysql-test/t/select.test:
  Manual merge

into  zippy.cornsilk.net:/home/cmiller/work/mysql/bug25807/my51-bug25807


BitKeeper/etc/collapsed:
  auto-union
mysys/mf_iocache.c:
  Auto merged

Showstopper and regression against 5.0.24.

Previously, we ignored seek() errors (see Bug#22828) and let seek()s
against pipes fail.  Now, since we check that a seek didn't fail,
and return without reading, this bug popped up.

This restores the behavior for file-ish objects that could never be 
seek()ed.


mysys/mf_iocache.c:
  If we detect early that the file is not tell()able, then we should
  assume that it's also not seek()able and therefore we should never
  set the (poorly named) "seek_not_done" flag so that we don't immedi-
  ately try to seek() when reading later.
  
  The problem was that tell() was returning -1, so when we read later, 
  we needlessly tried to seek to position  (unsigned long) -1 . 
  
  Also, if we think we're supposed to seek to a position in a file and 
  the file is un-tell()able, then abort.

into  olga.mysql.com:/home/igor/mysql-5.1-opt


mysql-test/r/view.result:
  Auto merged
sql/sql_select.cc:
  Auto merged
mysql-test/t/view.test:
  Manual merge

into  bk-internal.mysql.com:/data0/bk/mysql-4.1-opt

into  chilla.local:/home/mydev/mysql-5.1-bug25460

into  chilla.local:/home/mydev/mysql-5.1-bug25460-old

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


sql/item.cc:
  Auto merged
sql/item_cmpfunc.cc:
  Auto merged
sql/item_cmpfunc.h:
  Auto merged
sql/sql_select.cc:
  Auto merged

into  zippy.cornsilk.net:/home/cmiller/work/mysql/tmpmerge

Under high load it was possible that memory mapping was started on a table
while other threads were working with the table.

I fixed the start of memory mapping so that it is done at the first table
open or when the requesting thread is using the table exclusively only.


include/my_base.h:
  Bug#25460 - High concurrency MyISAM access causes severe mysqld crash.
  Added a new MyISAM open_flag HA_OPEN_MMAP.
storage/myisam/ha_myisam.cc:
  Bug#25460 - High concurrency MyISAM access causes severe mysqld crash.
  Replaced the call to mi_extra(... HA_EXTRA_MMAP ...) by the new open_flag
  HA_OPEN_MMAP. This effects that the mapping will no longer be done on
  every open of the table but just on the initial open, when the MyISAM
  share is created.
storage/myisam/mi_dynrec.c:
  Bug#25460 - High concurrency MyISAM access causes severe mysqld crash.
  Added a comment with a concern regarding the mmap flag MAP_NORESERVE.
storage/myisam/mi_extra.c:
  Bug#25460 - High concurrency MyISAM access causes severe mysqld crash.
  Limited the start of memory mapping to situations where the requesting
  thread has the table exclusively opened.
storage/myisam/mi_open.c:
  Bug#25460 - High concurrency MyISAM access causes severe mysqld crash.
  Added memory mapping code. Used if the new open_flag HA_OPEN_MMAP is set.

  Rename: BitKeeper/deleted/.del-README.txt -> BitKeeper/deleted/.del-README.txt-renamed


BitKeeper/deleted/.del-README.txt-renamed:
  Rename: BitKeeper/deleted/.del-README.txt -> BitKeeper/deleted/.del-README.txt-renamed

into  zippy.cornsilk.net:/home/cmiller/work/mysql/mysql-5.1-maint


sql/mysql_priv.h:
  manual merge.

into  zippy.cornsilk.net:/home/cmiller/work/mysql/mysql-5.0-maint


sql/mysql_priv.h:
  Auto merged

BitKeeper/deleted/.del-README.txt~97cdd3dccd3539d2:
  Delete: mysql-test/suite/objects/README.txt
BitKeeper/deleted/.del-drop_all.inc:
  Delete: mysql-test/suite/objects/include/drop_all.inc
BitKeeper/deleted/.del-objects.inc:
  Delete: mysql-test/suite/objects/include/objects.inc
BitKeeper/deleted/.del-tbl01.inc:
  Delete: mysql-test/suite/objects/include/tbl01.inc
BitKeeper/deleted/.del-tbl02.inc:
  Delete: mysql-test/suite/objects/include/tbl02.inc
BitKeeper/deleted/.del-tbl03.inc:
  Delete: mysql-test/suite/objects/include/tbl03.inc
BitKeeper/deleted/.del-tbl04.inc:
  Delete: mysql-test/suite/objects/include/tbl04.inc
BitKeeper/deleted/.del-tbl05.inc:
  Delete: mysql-test/suite/objects/include/tbl05.inc
BitKeeper/deleted/.del-tbl06.inc:
  Delete: mysql-test/suite/objects/include/tbl06.inc
BitKeeper/deleted/.del-tbl07.inc:
  Delete: mysql-test/suite/objects/include/tbl07.inc
BitKeeper/deleted/.del-tbl08.inc:
  Delete: mysql-test/suite/objects/include/tbl08.inc
BitKeeper/deleted/.del-tbl09.inc:
  Delete: mysql-test/suite/objects/include/tbl09.inc
BitKeeper/deleted/.del-tbl10.inc:
  Delete: mysql-test/suite/objects/include/tbl10.inc
BitKeeper/deleted/.del-tbl11.inc:
  Delete: mysql-test/suite/objects/include/tbl11.inc
BitKeeper/deleted/.del-tbl12.inc:
  Delete: mysql-test/suite/objects/include/tbl12.inc
BitKeeper/deleted/.del-tbl13.inc:
  Delete: mysql-test/suite/objects/include/tbl13.inc
BitKeeper/deleted/.del-tbl14.inc:
  Delete: mysql-test/suite/objects/include/tbl14.inc
BitKeeper/deleted/.del-tbl15.inc:
  Delete: mysql-test/suite/objects/include/tbl15.inc
BitKeeper/deleted/.del-tbl16.inc:
  Delete: mysql-test/suite/objects/include/tbl16.inc
BitKeeper/deleted/.del-tbl17.inc:
  Delete: mysql-test/suite/objects/include/tbl17.inc
BitKeeper/deleted/.del-tbl18.inc:
  Delete: mysql-test/suite/objects/include/tbl18.inc
BitKeeper/deleted/.del-tbl19.inc:
  Delete: mysql-test/suite/objects/include/tbl19.inc
BitKeeper/deleted/.del-tbl20.inc:
  Delete: mysql-test/suite/objects/include/tbl20.inc
BitKeeper/deleted/.del-tbl21.inc:
  Delete: mysql-test/suite/objects/include/tbl21.inc
BitKeeper/deleted/.del-tbl22.inc:
  Delete: mysql-test/suite/objects/include/tbl22.inc
BitKeeper/deleted/.del-tbl23.inc:
  Delete: mysql-test/suite/objects/include/tbl23.inc
BitKeeper/deleted/.del-tbl24.inc:
  Delete: mysql-test/suite/objects/include/tbl24.inc
BitKeeper/deleted/.del-tbl25.inc:
  Delete: mysql-test/suite/objects/include/tbl25.inc
BitKeeper/deleted/.del-tbl26.inc:
  Delete: mysql-test/suite/objects/include/tbl26.inc
BitKeeper/deleted/.del-tbl27.inc:
  Delete: mysql-test/suite/objects/include/tbl27.inc
BitKeeper/deleted/.del-tbl28.inc:
  Delete: mysql-test/suite/objects/include/tbl28.inc
BitKeeper/deleted/.del-tbl29.inc:
  Delete: mysql-test/suite/objects/include/tbl29.inc
BitKeeper/deleted/.del-tbl30.inc:
  Delete: mysql-test/suite/objects/include/tbl30.inc
BitKeeper/deleted/.del-tbl31.inc:
  Delete: mysql-test/suite/objects/include/tbl31.inc
BitKeeper/deleted/.del-tbl32.inc:
  Delete: mysql-test/suite/objects/include/tbl32.inc
BitKeeper/deleted/.del-tbl33.inc:
  Delete: mysql-test/suite/objects/include/tbl33.inc
BitKeeper/deleted/.del-tbl34.inc:
  Delete: mysql-test/suite/objects/include/tbl34.inc
BitKeeper/deleted/.del-tbl35.inc:
  Delete: mysql-test/suite/objects/include/tbl35.inc
BitKeeper/deleted/.del-tbl36.inc:
  Delete: mysql-test/suite/objects/include/tbl36.inc
BitKeeper/deleted/.del-tbl37.inc:
  Delete: mysql-test/suite/objects/include/tbl37.inc
BitKeeper/deleted/.del-tbl38.inc:
  Delete: mysql-test/suite/objects/include/tbl38.inc
BitKeeper/deleted/.del-tbl39.inc:
  Delete: mysql-test/suite/objects/include/tbl39.inc
BitKeeper/deleted/.del-tbl40.inc:
  Delete: mysql-test/suite/objects/include/tbl40.inc
BitKeeper/deleted/.del-tbl41.inc:
  Delete: mysql-test/suite/objects/include/tbl41.inc
BitKeeper/deleted/.del-tbl42.inc:
  Delete: mysql-test/suite/objects/include/tbl42.inc
BitKeeper/deleted/.del-tbl43.inc:
  Delete: mysql-test/suite/objects/include/tbl43.inc
BitKeeper/deleted/.del-tbl44.inc:
  Delete: mysql-test/suite/objects/include/tbl44.inc
BitKeeper/deleted/.del-tbl45.inc:
  Delete: mysql-test/suite/objects/include/tbl45.inc
BitKeeper/deleted/.del-tbl46.inc:
  Delete: mysql-test/suite/objects/include/tbl46.inc
BitKeeper/deleted/.del-tbl47.inc:
  Delete: mysql-test/suite/objects/include/tbl47.inc
BitKeeper/deleted/.del-tbl48.inc:
  Delete: mysql-test/suite/objects/include/tbl48.inc
BitKeeper/deleted/.del-view.inc:
  Delete: mysql-test/suite/objects/include/view.inc
BitKeeper/deleted/.del-objects_falcon.result:
  Delete: mysql-test/suite/objects/r/objects_falcon.result
BitKeeper/deleted/.del-objects_falcon.test:
  Delete: mysql-test/suite/objects/t/objects_falcon.test
BitKeeper/deleted/.del-objects_innodb.result:
  Delete: mysql-test/suite/objects/r/objects_innodb.result
BitKeeper/deleted/.del-objects_innodb.test:
  Delete: mysql-test/suite/objects/t/objects_innodb.test

into  olga.mysql.com:/home/igor/mysql-5.1-opt


BitKeeper/etc/gone:
  auto-union
mysql-test/r/insert_select.result:
  Auto merged
mysql-test/r/join_outer.result:
  Auto merged
mysql-test/r/select.result:
  Auto merged
mysql-test/r/view.result:
  Auto merged
mysql-test/t/insert_select.test:
  Auto merged
mysql-test/t/join_outer.test:
  Auto merged
mysql-test/t/select.test:
  Auto merged
mysys/my_getopt.c:
  Auto merged
sql/field.h:
  Auto merged
sql/field_conv.cc:
  Auto merged
sql/item.cc:
  Auto merged
sql/item_cmpfunc.cc:
  Auto merged
sql/item_cmpfunc.h:
  Auto merged
sql/item_func.cc:
  Auto merged
sql/sql_lex.cc:
  Auto merged
sql/sql_prepare.cc:
  Auto merged
sql/sql_select.cc:
  Auto merged
sql/sql_show.cc:
  Auto merged
sql/sql_view.cc:
  Auto merged
sql/table.cc:
  Auto merged
sql/table.h:
  Auto merged
mysql-test/include/mix1.inc:
  Manual merge
mysql-test/r/information_schema.result:
  Manual merge
mysql-test/r/innodb_mysql.result:
  Manual merge
mysql-test/t/information_schema.test:
  Manual merge
mysql-test/t/view.test:
  Manual merge
mysys/my_pthread.c:
  Manual merge
sql/mysql_priv.h:
  Manual merge
sql/opt_range.cc:
  Manual merge
sql/sql_insert.cc:
  Manual merge
sql/sql_update.cc:
  Manual merge

into  pilot.mysql.com:/home/msvensson/mysql/mysql-5.1-new-maint


BitKeeper/etc/gone:
  auto-union
BitKeeper/etc/ignore:
  auto-union
mysys/my_getopt.c:
  Auto merged
sql/sql_prepare.cc:
  Auto merged
sql/table.cc:
  Auto merged
sql/unireg.cc:
  Auto merged
mysql-test/r/type_enum.result:
  Use local
mysql-test/t/type_enum.test:
  Use local

into  pilot.mysql.com:/home/msvensson/mysql/mysql-5.1-new-maint


BitKeeper/etc/ignore:
  auto-union

into  pilot.mysql.com:/home/msvensson/mysql/mysql-5.0-maint


BitKeeper/etc/ignore:
  auto-union