columns again

This is follow-up to Bug #54358. Not all occurrences of the bug were fixed.
We need to check all calls to btr_copy_externally_stored_field_prefix_low()
and do the right thing when the pointer to the off-page column is null
(full of zero bytes).

It turns out that only the call to btr_copy_externally_stored_field_prefix()
in row_sel_sec_rec_is_for_blob() needs to be changed.

For fetching complete off-page columns rather than prefixes, the function
btr_rec_copy_externally_stored_field() already checks if the pointer
is null (all-zero).  Two of its callers (row_merge_copy_blobs() and
row_sel_fetch_columns()) are never executed as READ COMMITTED and can
rightfully assert that the fetch succeeded.  The third caller,
row_sel_store_mysql_rec(), already does the right thing.

The calls in row_upd_ext_fetch() and trx_undo_page_fetch_ext() must
expect that the off-page column exists. Update and rollback are
locking operations, never READ UNCOMMITTED.

btr_estimate_n_rows_in_range_on_level(): Always do mtr_commit(),
so that the page will not remain pinned indefinitely.

/export/home/pb2/build/sb_0-2459340-1288264809.63/mysql-5.5.8-ga/storage/innobase/os/os0sync.c: In function 'os_cond_wait_timed':
/export/home/pb2/build/sb_0-2459340-1288264809.63/mysql-5.5.8-ga/storage/innobase/os/os0sync.c:184: warning: format '%lu' expects type 'long unsigned int', but argument 4 has type 'time_t'
gmake[2]: *** [storage/innobase/CMakeFiles/innobase.dir/os/os0sync.c.o] Error 1 

On Windows, the parameter for number of bytes passed into WriteFile()
and ReadFile() is DWORD. Casting is needed to silence the warning on
64-bit Windows.

Also, adding several asserts to ensure the variable for number of bytes
is no more than 32 bits, even on 64-bit Windows.

rb://415
Approved by: Inaam

On Windows, the parameter for number of bytes passed into WriteFile()
and ReadFile() is DWORD. Casting is needed to silence the warning on
64-bit Windows.

Also, adding several asserts to ensure the variable for number of bytes
is no more than 32 bits, even on 64-bit Windows.

This is for InnoDB Plugin.

rb://415
Approved by: Inaam

On Windows, the parameter for number of bytes passed into WriteFile()
and ReadFile() is DWORD. Casting is needed to silence the warning on
64-bit Windows.

Also, adding several asserts to ensure the variable for number of bytes
is no more than 32 bits, even on 64-bit Windows.

This is for built-in InnoDB.

rb://415
Approved by: Inaam

a compile error with MSVC. The problem was introduced in Revision: 3150
revid:marko.makela@oracle.com-20100809085837-s1nfx6gjf7l6ttab

buf_pool_init(): Replace ut_ad(n_instances < MAX_BUFFER_POOLS)
with ut_ad(n_instances <= MAX_BUFFER_POOLS).
(Spotted by Michael Izioumtchenko.)
Add ut_ad(n_instances > 0).

buf_page_t: Remove the buf_pool pointer. Add buf_pool_index:6 next to
buf_fix_count:19 (it was buf_fix_count:25). This will limit the number
of concurrent transactions to somewhere around 524,288.

buf_pool_index(buf_pool): A new function to determine the index of a
buffer pool in buf_pool_ptr[].

buf_pool_ptr: Make this a dynamically allocated array instead of an
array of pointers. Allocate the array in buf_pool_init() and free in
buf_pool_free().

buf_pool_free_instance(): No longer free the buf_pool object, as it is
allocated from a big array.

buf_pool_from_bpage(), buf_pool_from_block(): Move the definitions to
the beginning of the files, because some compilers have (had) problems
with forward definitions of inline functions. Calculate the buffer
pool from buf_pool_index.

buf_pool_from_array(): Add debug assertions for input validation.

CMakeLists.txt: Remove the checks for mysql_storage_engine.cmake
and MYSQL_VERSION_ID.

ha_innodb.cc, ha_innodb.h: Remove the checks for MYSQL_VERSION_ID.

  rb://498
  
  Fix handling of update_undo_logs at trx commit. Previously, when
  rseg->update_undo_list grows beyond 500 the update_undo_logs were
  marked with state TRX_UNDO_TO_FREE which should have been
  TRX_UNDO_TO_PURGE.
  In 5.5 we don't need the heuristic as we support multiple rollback
  segments.
  
  Approved by: Sunny Bains

rb://498

Fix handling of update_undo_logs at trx commit. Previously, when
rseg->update_undo_list grows beyond 500 the update_undo_logs were
marked with state TRX_UNDO_TO_FREE which should have been
TRX_UNDO_TO_PURGE.

Approved by: Sunny Bains

Bug#57720 - Windows Vista and possibly Windows 7 can return ERROR_TIMEOUT instead of WAIT_TIMEOUT from calls to SleepConditionVariableCS() which is used in os0sync.c; os_cond_wait_timeout() where it is mapped to sleep_condition_variable().   

Consider ERROR_TIMEOUT to be a timeout just like WAIT_TIMEOUT.  

In addition, test for EINTR as a possible return value from pthread_cond_timeout() in the posix section of os_cond_wait_timeout(), even though it is not supposed to be returned, but just to be safe.

COM_CHANGE_USER was always handled like an implicit request to change the
client plugin, so that the client can re-use the same code path for both normal 
login and COM_CHANGE_USER. However this doesn't really work well with old 
clients because they don't understand the request to change a client plugin.

Fixed by implementing a special state in the code (and old client issuing 
COM_CHANGE_USER). In this state the server parses the COM_CHANGE_USER 
package and pushes back the password hash, the user name and the database 
to the input stream in the same order that the native password server side plugin 
expects. As a result it replies with an OK/FAIL just like the old server does thus
making the new server compatible with older clients.

No test case added, since it would requre an old client binary. Tested using 
accounts with and without passwords. Tested with a correct and incorrect 
password.

The problem was that the warnings risen by a trigger were not cleared upon
successful completion. The warnings should be cleared if the trigger completes
successfully.

The fix is to skip merging warnings into caller's Warning Info for triggers.

sql/sql_lex.h:1437: warning: control reaches end of non-void function

Boolean options cause parsing failures when they are given
with prefix loose- and an argument, either in the command
line or in configuration file.

The reason was a faulty logic which forced the parsing
to throw an error when an argument of type NO_ARG was
used together with an argument which has been identified
as a key-value pair. Despite the attribute NO_ARG these
options actually take arguments if they are of type
BOOL.