automatic reconnect

A client with automatic reconnect enabled will see the error
message "Lost connection to MySQL server during query" if the
connection is lost between mysql_stmt_prepare() and
mysql_stmt_execute(). The mysql_stmt_errno() number, however,
is 0 -- not the corresponding value 2013.

This patch checks for the case where the prepared statement
has been pruned due to a connection loss (i.e., stmt->mysql
has been set to NULL) during a call to cli_advanced_command(),
and avoids changing the last_errno to the result of the last
reconnect attempt.

The default value of the myisam_max_extra_sort_file_size could be
higher than the maximum accepted value, leading to warnings upon
the server start.

The solution is to simply set the value to the maximum value in a
32-bit built (2147483647, one less than the current). This should
be harmless as the option is currently unused in 5.1.

include/myisam.h:
  Remove now-unused macro.
sql/mysqld.cc:
  Set max value to INT_MAX32.

The problem was that a user could supply supply data in chunks
via the COM_STMT_SEND_LONG_DATA command to prepared statement
parameter other than of type TEXT or BLOB. This posed a problem
since other parameter types aren't setup to handle long data,
which would lead to a crash when attempting to use the supplied
data.

Given that long data can be supplied at any stage of a prepared
statement, coupled with the fact that the type of a parameter
marker might change between consecutive executions, the solution
is to validate at execution time each parameter marker for which
a data stream was provided. If the parameter type is not TEXT or
BLOB (that is, if the type is not able to handle a data stream),
a error is returned.

sql/sql_prepare.cc:
  Before converting the parameter data stream, check the type
  compatibility.
tests/mysql_client_test.c:
  Add test case.

DROP USER 
RENAME USER CURRENT_USER() ...
GRANT ... TO CURRENT_USER()
REVOKE ... FROM CURRENT_USER()
ALTER DEFINER = CURRENT_USER() EVENTbut, When these statements are binlogged, CURRENT_USER() just is binlogged
as 'CURRENT_USER()', it is not expanded to the real user name. When slave 
executes the log event, 'CURRENT_USER()' is expand to the user of slave 
SQL thread, but SQL thread's user name always NULL. This breaks the replication.

After this patch, session's user will be written into query log events 
if these statements call CURREN_USER() or 'ALTER EVENT' does not assign a definer.


mysql-test/include/diff_tables.inc:
  Expend its abilities.
  Now it can diff not only in sessions of 'master' and 'slave', but 
  other sessions as well.
mysql-test/include/rpl_diff_tables.inc:
  Diff the same table between master and slaves.
sql/log_event.cc:
  session's user will be written into Query_log_event, if is_current_user_used() is TRUE.
  On slave SQL thread, Only thd->variables.current_user is written into Query_log_event,
  if it exists.
sql/sql_acl.cc:
  On slave SQL thread, grantor should copy from thd->variables.current_user, if it exists
sql/sql_class.h:
  On slave SQL thread, thd->variables.current_user is used to store the applying event's
  invoker.

This deadlock happened if DROP DATABASE was blocked due to an open
HANDLER table from a different connection. While DROP DATABASE
is blocked, it holds the LOCK_mysql_create_db mutex. This results
in a deadlock if the connection with the open HANDLER table tries
to execute a CREATE/ALTER/DROP DATABASE statement as they all
try to acquire LOCK_mysql_create_db.

This patch makes this deadlock scenario very unlikely by closing and
marking for re-open all HANDLER tables for which there are pending
conflicing locks, before LOCK_mysql_create_db is acquired.
However, there is still a very slight possibility that a connection
could access one of these HANDLER tables between closing/marking for
re-open and the acquisition of LOCK_mysql_create_db.

This patch is for 5.1 only, a separate and complete fix will be
made for 5.5+.

Test case added to schema.test.

During creation of the table list of
processed tables hidden I_S table 'VARIABLES'
is erroneously added into the table list.
it leads to ER_UNKNOWN_TABLE error in
TABLE_LIST::add_table_to_list() function.
The fix is to skip addition of hidden I_S
tables into the table list.


mysql-test/r/information_schema.result:
  test case
mysql-test/t/information_schema.test:
  test case
sql/sql_show.cc:
  The fix is to skip addition of hidden I_S
  tables into the table list.

require O(#scans) memory

When an index merge operation was restarted, it would
re-allocate the Unique object controlling the duplicate row
ID elimination. Fixed by making the Unique object a member
of QUICK_INDEX_MERGE_SELECT and thus reusing it throughout
the lifetime of this object.

file .\filesort.cc, line 149 (part II)

Problem: the server didn't disregard sort order 
for some zero length tuples.

Fix: skip sort order in such a case 
(zero length NOT NULL string functions).


mysql-test/r/select.result:
  Fix for bug #54459: Assertion failed: param.sort_length, 
  file .\filesort.cc, line 149 (part II)
    - test result.
mysql-test/t/select.test:
  Fix for bug #54459: Assertion failed: param.sort_length, 
  file .\filesort.cc, line 149 (part II)
    - test case.
sql/sql_select.cc:
  Fix for bug #54459: Assertion failed: param.sort_length, 
  file .\filesort.cc, line 149 (part II)
    - disregard sort order for zero length NOT NULL string functions
  along with zero length NOT NULL fields.

Incorrect handling of NULL arguments could lead to a crash on
the IN or CASE operations when either NULL arguments were
passed explicitly as arguments (IN) or implicitly generated by
the WITH ROLLUP modifier (both IN and CASE).

Item_func_case::find_item() assumed all necessary comparators
to be instantiated in fix_length_and_dec(). However, in the
presence of WITH ROLLUP modifier, arguments could be
substituted with an Item_null leading to an "unexpected"
STRING_RESULT comparator being invoked.

In addition to the problem identical to the above,
Item_func_in::val_int() could crash even with explicitly passed
NULL arguments due to an optimization in fix_length_and_dec()
leading to NULL arguments being ignored during comparators
creation.


mysql-test/r/func_in.result:
  Test cases for bug#54477.
mysql-test/t/func_in.test:
  Test cases for bug#54477.
sql/item_cmpfunc.cc:
  Added additional checks for Item_nulls in 
  Item_func_case::find_item() and Item_func_in::val_int().

In process of record search it is not taken into account
that inital quick->file->ref value could be inapplicable
to range interval. After proper row is found this value is
stored into the record buffer and later the record is
filtered out at condition evaluation stage.
The fix is store a refernce of found row to the handler ref field.


mysql-test/r/innodb_mysql.result:
  test case
mysql-test/std_data/intersect-bug50389.tsv:
  test case
mysql-test/t/innodb_mysql.test:
  test case
sql/opt_range.cc:
  store a refernce of found row to the handler ref field.

Problem: a flaw (derefencing a NULL pointer) in the LIKE optimization
code may lead to a server crash in some rare cases.

Fix: check the pointer before its dereferencing.


mysql-test/r/func_like.result:
  Fix for bug #54575: crash when joining tables with unique set column
    - test result.
mysql-test/t/func_like.test:
  Fix for bug #54575: crash when joining tables with unique set column
    - test case.
sql/item_cmpfunc.cc:
  Fix for bug #54575: crash when joining tables with unique set column
    - check res2 buffer pointer before its dereferencing 
  as it may be NULL in some cases.

mysql_client_binlog_statement

Problem: server may read from unassigned memory performing
"wrong" BINLOG queries.

Fix: never read from unassigned memory.


mysql-test/suite/binlog/r/binlog_base64_flag.result:
  Fix for bug #54393: crash and/or valgrind errors in
  mysql_client_binlog_statement
    - test result.
mysql-test/suite/binlog/t/binlog_base64_flag.test:
  Fix for bug #54393: crash and/or valgrind errors in
  mysql_client_binlog_statement
    - test case.
sql/sql_binlog.cc:
  Fix for bug #54393: crash and/or valgrind errors in
  mysql_client_binlog_statement
    - coded_len should not count trailing '/0';
    - never read from unassigned memory.

line exceeds the limit

Upmerge the fix from 5.0 to 5.1

           line exceeds the limit

The number and/or names of our files for the main test suite
(contents of "mysql-test/t/") now exceeds the command line
length limit on AIX.
Solve the problem by using separate "cp" commands for the
various file name extensions.

This is the fix for 5.1, where only the behaviour on upgrade is changed:
If the server was stopped when the upgrade begins, we assume the
administrator is taking manual action, so we do not start the (new)
server at the end of the upgrade.
We still install the start/stop script, so it will be started on reboot.


support-files/mysql.spec.sh:
  In the "pre" section of the spec file, check the server status, and write
  the result to a file.
  In the "post" section, evaluate the status file, and start the server if
  it was running during status analysis.
  In 5.1, we start the server if there is no status file (which will happen
  on first installation, when there is no data directory yet).

root cause of 52208 resulted in another test failure
in 5.1.

Reorder code breaks when finding tests skipped due to --skip-rpl etc.
Add simple test that master_opt is non-empty

Kill mysqltest and call mtr_kill_leftovers() before terminating

In Prepared_statement::prepare() bail out as soon as
parser_state.init() fails, trying to continue leads to crashes.

conflicts:
   conflict      sql/sql_parse.cc

Item*) at opt_sum.cc:305
      
Queries applying MIN/MAX functions to indexed columns are
optimized to read directly from the index if all key parts
of the index preceding the aggregated key part are bound to
constants by the WHERE clause. A prefix length is also
produced, equal to the total length of the bound key
parts. If the aggregated column itself is bound to a
constant, however, it is also included in the prefix.

Such full search keys are read as closed intervals for
reasons beyond the scope of this bug. However, the procedure
missed one case where a key part meant for use as range
endpoint was being overwritten with a NULL value destined
for equality checking. In this case the key part was
overwritten but the range flag remained, causing open
interval reading to be performed.

Bug was fixed by adding more stringent checking to the
search key building procedure (matching_cond) and never
allow overwrites of range predicates with non-range
predicates.

An assertion was added to make sure open intervals are never
used with full search keys.

            strict aliasing violations.

One somewhat major source of strict-aliasing violations and
related warnings is the SQL_LIST structure. For example,
consider its member function `link_in_list` which takes
a pointer to pointer of type T (any type) as a pointer to
pointer to unsigned char. Dereferencing this pointer, which
is done to reset the next field, violates strict-aliasing
rules and might cause problems for surrounding code that
uses the next field of the object being added to the list.

The solution is to use templates to parametrize the SQL_LIST
structure in order to deference the pointers with compatible
types. As a side bonus, it becomes possible to remove quite
a few casts related to acessing data members of SQL_LIST.

sql/handler.h:
  Use the appropriate template type argument.
sql/item.cc:
  Remove now-unnecessary cast.
sql/item_subselect.cc:
  Remove now-unnecessary casts.
sql/item_sum.cc:
  Use the appropriate template type argument.
  Remove now-unnecessary cast.
sql/mysql_priv.h:
  Move SQL_LIST structure to sql_list.h
  Use the appropriate template type argument.
sql/sp.cc:
  Remove now-unnecessary casts.
sql/sql_delete.cc:
  Use the appropriate template type argument.
  Remove now-unnecessary casts.
sql/sql_derived.cc:
  Remove now-unnecessary casts.
sql/sql_lex.cc:
  Remove now-unnecessary casts.
sql/sql_lex.h:
  SQL_LIST now takes a template type argument which must
  match the type of the elements of the list. Use forward
  declaration when the type is not available, it is used
  in pointers anyway.
sql/sql_list.h:
  Rename SQL_LIST to SQL_I_List. The template parameter is
  the type of object that is stored in the list.
sql/sql_olap.cc:
  Remove now-unnecessary casts.
sql/sql_parse.cc:
  Remove now-unnecessary casts.
sql/sql_prepare.cc:
  Remove now-unnecessary casts.
sql/sql_select.cc:
  Remove now-unnecessary casts.
sql/sql_show.cc:
  Remove now-unnecessary casts.
sql/sql_table.cc:
  Remove now-unnecessary casts.
sql/sql_trigger.cc:
  Remove now-unnecessary casts.
sql/sql_union.cc:
  Remove now-unnecessary casts.
sql/sql_update.cc:
  Remove now-unnecessary casts.
sql/sql_view.cc:
  Remove now-unnecessary casts.
sql/sql_yacc.yy:
  Remove now-unnecessary casts.
storage/myisammrg/ha_myisammrg.cc:
  Remove now-unnecessary casts.

           strict aliasing violations.

Essentially, the problem is that large parts of the server were
developed in simpler times (last decades, pre C99 standard) when
strict aliasing and compilers supporting such optimizations were
rare to non-existent. Thus, when compiling the server with a modern
compiler that uses strict aliasing rules to perform optimizations,
there are several places in the code that might trigger undefined
behavior.

As evinced by some recent bugs, GCC does a somewhat good of job
misoptimizing such code, but on the other hand also gives warnings
about suspicious code. One problem is that the warnings aren't
always accurate, yet we can't afford to just shut them off as we
might miss real cases. False-positive cases are aggravated mostly
by casts that are likely to trigger undefined behavior.

The solution is to start a cleanup process focused on fixing and
reducing the amount of strict-aliasing related warnings produced
by GCC and others compilers. A good deal of noise reduction can
be achieved by just removing useless casts that are product of
historical cruft and are likely to trigger undefined behavior if
dereferenced.

client/mysql.cc:
  Remove now-unnecessary casts.
  Break up large strings.
client/mysql_upgrade.c:
  Remove now-unnecessary casts.
client/mysqladmin.cc:
  Remove now-unnecessary casts.
  Break up large strings.
client/mysqlbinlog.cc:
  Remove now-unnecessary casts.
client/mysqlcheck.c:
  Remove now-unnecessary casts.
client/mysqldump.c:
  Remove now-unnecessary casts.
client/mysqlimport.c:
  Remove now-unnecessary casts.
client/mysqlshow.c:
  Remove now-unnecessary casts.
client/mysqlslap.c:
  Remove now-unnecessary casts.
client/mysqltest.cc:
  Remove now-unnecessary casts.
extra/comp_err.c:
  Remove now-unnecessary casts.
extra/my_print_defaults.c:
  Remove now-unnecessary casts.
  Break up large strings.
extra/mysql_waitpid.c:
  Remove now-unnecessary casts.
extra/perror.c:
  Remove now-unnecessary casts.
extra/resolve_stack_dump.c:
  Remove now-unnecessary casts.
extra/resolveip.c:
  Remove now-unnecessary casts.
include/my_getopt.h:
  Use a void pointer type as the opaque type to avoid problems with type
  incompatibility -- GCC issues warnings when the type name is not type
  compatible with a operand. As a side bonus, a explicit cast won't be
  necessary anymore.
include/sslopt-longopts.h:
  Remove now-unnecessary casts.
  Break up large strings.
mysys/my_getopt.c:
  Update opaque type and introduce a type definition for the
  argument to my_getopt_register_get_addr.
server-tools/instance-manager/options.cc:
  Remove now-unnecessary casts.
sql/mysqld.cc:
  Remove now-unnecessary casts.
  Break up large strings.
  Update mysql_getopt_value prototype (the old prototype
  was different from the definition anyway).
sql/sql_plugin.cc:
  The type of a pointer to a function must be compatible with the
  pointed-to function type, otherwise the behavior is undefined.
sql/table.cc:
  The variable buf pointer to pointer to pointer to constant char
  could improperly alias a incompatible type in call to fix_type_
  pointers. Since this was actually dead code, it is simply removed.
sql/unireg.cc:
  Remove call to get_form_pos. The code creates a new FRM file which
  is always truncated and writes the form position as 0. Hence, no
  need to retrieve it, we now for sure it is 0.
storage/archive/archive_reader.c:
  Remove now-unnecessary casts.
storage/myisam/ft_nlq_search.c:
  Read weight directly from the buffer.
storage/myisam/fulltext.h:
  Add explanation about the type duality of a key buffer.
  Add accessor macro to retrieve a FT float value.
storage/myisam/mi_test1.c:
  Remove now-unnecessary casts.
storage/myisam/myisam_ftdump.c:
  Read weight directly from the buffer.
storage/myisam/myisamchk.c:
  Remove now-unnecessary casts.
storage/myisam/myisamlog.c:
  A pointer to char was used to alias a pointer to pointer to
  unsigned char, thus violating strict aliasing rules.
storage/myisam/myisampack.c:
  Remove now-unnecessary casts.
strings/decimal.c:
  Remove aliasing violation, printing the value is enough for
  debugging purposes.
tests/mysql_client_test.c:
  Remove now-unnecessary casts.

The bug was caused by buffered output. Flushing resolved it.
We still recommend to allways call plan().
  
Also fix some compile warnings (formal parameter different from declaration)


unittest/examples/Makefile.am:
  Omit core-t, since it will always fail.
unittest/examples/no_plan-t.c:
  Comment that we recommend calling plan(NO_PLAN)
unittest/mytap/tap.c:
  Use the named constant NO_PLAN
  Flush all output.
unittest/mytap/tap.h:
  Change documentation for the plan() function.