Fixing test case that fails on Windows because .dll is used.

When installing plugins, there is a missing check
for slash (/) in the path on Windows. Note that on
Windows, both / and \ can be used to separate
directories.

This patch fixes the issue by:
- Adding a FN_DIRSEP symbol for all platforms
  consisting of a string of legal directory
  separators.
- Adding a charset-aware version of strcspn().
- Adding a check_valid_path() function that uses
  my_strcspn() to check if any FN_DIRSEP character
  is in the supplied string.
- Using the check_valid_path() function in
  sql_plugin.cc and sql_udf.cc (which means
  replacing the existing test there).

This bogus assertion was introduced in the fix of Bug #57802:
Empty ASSERTION parameter passed to the HASH_SEARCH macro.

Fixing the testcase to use the database name
as connected_db instead of 'test' database.

integral type. Use intptr which is designed to hold pointer values
and pass it to off_t.

    
Code cleanup after changes for Bug 56628.  The general approach for 
InnoDB is to make a reference to each enum value whenever it is used in a
switch statement.  In addition, no default case should be used for switch 
statements on enum types.  This assures that if there is ever any change 
in the enum values, the switch will need to change to reflect it since a 
compiler warning will occur.  In this case, the enum row_type is declared 
in handler.h and could be changed for another storage engine.  If so, a 
warning will occur in the InnoDB build.  

Other changes;
* This patch uses 2 macros to help consolidate warning messages that
   need to occur twice in the single switch for row_format.
* Using row_format as the variable name to distinguish it from the enum
  type.
* Function declaration format correction.

When using BINLOG statement to execute rows log events, session variables
foreign_key_checks and unique_checks are changed temporarily.  As each rows
log event has their own special session environment and its own
foreign_key_checks and unique_checks can be different from current session
which executing the BINLOG statement. But these variables are not restored
correctly after BINLOG statement. This problem will cause that the following
statements fail or generate unexpected data.

In this patch, code is added to backup and restore these two variables.
So BINLOG statement will not affect current session's variables again.

The problem is that the logic which checks if a pointer is
valid relies on a poor heuristic based on the start and end
addresses of the data segment and heap.

Apart from miscalculating the heap bounds, this approach also
suffers from the fact that memory can come from places other
than the heap. See Bug#58528 for a more detailed explanation.

On Linux, the solution is to access the process's memory
through /proc/self/task/<tid>/mem, which allows for retrieving
the contents of pages within the virtual address space of
the calling process. If a address range is not mapped, a
input/output error is returned.

the DROP statement ..."
      
Problem: When using temporary tables and closing a session, an
implicit DROP TEMPORARY TABLE IF EXISTS is written to the binary
log (while cleaning up the context of the session THD - see:
sql_class.cc:THD::cleanup which calls close_temporary_tables).
     
close_temporary_tables, first checks if the binary log is opened
and then proceeds to creating the DROP statements. Then, such
statements, are written to the binary log through
MYSQL_BIN_LOG::write(Log_event *). Inside, there is another check
if the binary log is opened and if not an error is returned. This
is where the faulty behavior is triggered. Given that the test
case replays a binary log, with temp tables statements, and right
after it issues RESET MASTER, there is a chance that is_open will
report false (when the mysql session is closed and the temporary
tables are written).
      
is_open may return false, because MYSQL_BIN_LOG::reset_logs is
not setting the correct flag (LOG_CLOSE_TO_BE_OPENED), on the
MYSQL_LOG_BIN::log_state (instead it sets just the
LOG_CLOSE_INDEX flag, leaving the log_state to
LOG_CLOSED). Thence, when writing the DROP statement as part of
the THD::cleanup, the thread could get a return value of false
for is_open - inside MYSQL_BIN_LOG::write, ultimately reporting
that it can't write the event to the binary log.
      
Fix: We fix this by adding the correct flag, missing in the
second close.

metadata"
            
Improved error handling such that queries against Information_Schema.Tables won't
fail if a federated table can't make a remote connection.

Improved error handling such that queries against Information_Schema.Tables won't
fail if a Federated table is unable to connect to remote host.

will not display "indicated result file not found" due to wrongly named
var directory.

Problem: MySQL cp1251 did not support 'U+20AC EURO SIGN'
which was assigned a few years ago to 0x88.

Fix: adding mapping: 0x88 <-> U+20AC 

  @ mysql-test/include/ctype_8bit.inc
  New shared file to test 8bit character sets.

  @ mysql-test/r/ctype_cp1251.result
  @ mysql-test/t/ctype_cp1251.test
  Adding tests

  @ sql/share/charsets/cp1251.xml
  Adding mapping

  @ strings/ctype-extra.c
  Regenerating ctype-extra.c using strings/conf_to_src
  according to new cp1251.xml

After dropping and recreating the database specified along with --one-database
option at command line, mysql client keeps filtering the statements even after
the execution of a 'USE' command on the same database.

--one-database option enables the filtering of statements when the current
database is not the one specified at the command line. However, when the same
database is dropped and recreated the variable (current_db) that holds the
inital database name gets altered. This bug exploits the fact that current_db
initially gets set to null value (0) when a 'use db_name' follows the recreation
of same database db_name (speficied at the command line) and hence skip_updates
gets set to 1, which inturn triggers the further filtering of statements.

Fixed by making get_current_db() a no-op function when one_database is set,
and hence, under that condition current_db will not get altered.
Note, however the value of current_db can change when we execute 'connect'
command with a differnet database to reconnect to the server, in which case,
the behavior of --one-database will be formulated using this new database.

Fixed as suggested in the .inc file and two tests
Could not reproduce problem, but tested tests on Windows

It does work in general, the problem here was that the test name
'alter_table' matches 'main.alter_table-big' which has already been found.
Fixed by matching more explicitly (with/without suite name)

Add a _commented_ workaround for Bug#47350. The full solution is tricky
to get right as explained in the bug report. It is not worth the effort
to extend the deprecated autotools framework to support conflicting
plugins and would be too risky for MySQL 5.1 (GA).

43233/55794.

EXCEPTIONS-CLIENT from all the places.

If mysqltest dies, mtr waits to see if mysqld dies too within 100ms
But in that case, it should not care about expected crash
Fix: jump past the code that checks the expect file