Third updated patch - this version also includes copyright notice in added Perl script.
This patch implements a check for such modules at runtime. If modules are not found or unable to load, the test is skipped with 
the following message:
            
            [ skipped ]  Test needs Perl modules DBI and DBD::mysql
            
Checks are done via a helper Perl script which looks for the module in a runtime environment that is as similar to that of the 
mysqlhotcopy script as possible (thus not intended for Windows environments at this time).
The helper script tells mysql-test about the result by writing information to a temporary file that is later read by mysql-test.
See comments in added files (have_dbi_dbd-mysql.inc and checkDBI_DBD-mysql.pl) for details.
The patch also removes the mysqlhotcopy tests from the list of disabled tests.

In SBR, if a statement does not fail, it is always written to the binary
log, regardless if rows are changed or not. If there is a failure, a
statement is only written to the binary log if a non-transactional (.e.g.
MyIsam) engine is updated.

INSERT ON DUPLICATE KEY UPDATE and INSERT IGNORE were not following the
rule above and were not written to the binary log, if then engine was
Innodb.

for external_size
      
rb://581 approved by Marko

There are two calls to read_log_event() on master in mysql_binlog_send().
Each call reads 19 bytes in this test case and the error of the second
read_log_event() is reported to the slave.

The second read_log_event() starts from position 94 (75 + 19) to 113
(75 + 19 + 19). Usually, there are two events in the binary log:

    . 0   - 3   - Header
    . 4   - 105 - Format Descriptor Event
    . 106 - 304 - Query Event

and both reads fail because operations are reading from invalid positions
as expected.

However, mysql_binlog_send() does not use the same IO_CACHE that is used to
write into binary log (i.e. mysql_bin_log.log_file) for the hot binary log.
It opens the binary log file directly by calling open_binlog() and creates a
separated IO_CACHE. So there is a possibly that after a master has flushed
the binary log file, the content has been cached by the filesystem, and has
not updated the disk file. If this happens, then a slave will only see part
of the file, and thus the second read_log_event() will report event truncated
error.

To fix the problem, if the first read_log_event() has failed, we ensure that
the second one will try to read from the same position.

trx_get_trx_by_xid(): Invalidate trx->xid after a successful lookup,
so that subsequent callers will not find the same transaction.

The only callers of trx_get_trx_by_xid() will be invoking
innobase_commit_low() or innobase_rollback_trx(), and those code paths
should not depend on trx->xid.

rb://584 approved by Jimmy Yang

No commit message

Fix backported from to 5.0.
"Remove the alignment option, let valgrind use its default"

Updated the copyright.

due to potentially uninitialized variable

row_upd_changes_ord_field_binary(): Initialize dfield_len to suppress the
warning. The compiler cannot know that row_ext_lookup() does initialize
dfield_len for us, as it is defined in a different module.

mlog_parse_string(): Enclose the comparison in UNIV_UNLIKELY,
not the comparand.

row_vers_build_for_semi_consistent_read(): Dereference version_trx before
releasing kernel_mutex, but not thereafter.

buf_block_alloc(): ulint zip_size is always 0.
buf_LRU_get_free_block(): ulint zip_size is always 0.
buf_LRU_free_block(): ibool* buf_pool_mutex_released is always NULL.

Remove these parameters.

buf_LRU_get_free_block(): Simplify the initialization of block->page.zip
and release buf_pool_mutex() earlier.

No commit message

Updated Copyright.

Race condition may occur: mtr sees the .expect file but it's empty
Fix: wait and try again if file is empty
Addendum: try again if line isn't 'wait' or 'restart'
Also added verbose printout of extra restart options

ZERO
      
When dates are represented internally as strings, i.e. when a string constant
is compared to a date value, both values are converted to long integers,
ostensibly for fast comparisons. DATE typed integer values are converted to
DATETIME by multiplying by 1,000,000 (each digit pair representing hour,
minute and second, respectively). But the mechanism did not distuinguish
cached INTEGER values, already in correct format, from newly converted
strings.

Fixed by marking the INTEGER cache as being of DATETIME format.

The test were using external tools not available for embedded.

Fixed by rewriting the test to not rely on external tools like the mysql-client

Also fixed some non portable --exec commands and replaced #p# to #P# to pass
on windows.