The root cause of this bug is related to the function skip_rear_comments,
in sql_lex.cc

Recent code changes in skip_rear_comments changed the prototype from
"const uchar*" to "const char*", which had an unforseen impact on this test:
  (endp[-1] < ' ')
With unsigned characters, this code filters bytes of value [0x00 - 0x20]
With *signed* characters, this also filters bytes of value [0x80 - 0xFF].

This caused the regression reported, considering cyrillic characters in the
parameter name to be whitespace, and truncated.
Note that the regression is present both in 5.0 and 5.1.

With this fix:
- [0x80 - 0xFF] bytes are no longer considered whitespace.
This alone fixes the regression.

In addition, filtering [0x00 - 0x20] was found bogus and abusive,
so that the code now filters uses my_isspace when looking for whitespace.

Note that this fix is only addressing the regression affecting UTF-8
in general, but does not address a more fundamental problem with
skip_rear_comments: parsing a string *backwards*, starting at end[-1],
is not safe with multi-bytes characters, so that end[-1] can confuse the
last byte of a multi-byte characters with a characters to filter out.

The only known impact of this remaining issue affects objects that have to
meet all the conditions below:

- the object is a FUNCTION / PROCEDURE / TRIGGER / EVENT / VIEW
- the body consist of only *1* instruction, and does *not* contain a
  BEGIN-END block
- the instruction ends, lexically, with <ident> <whitespace>* ';'?
  For example, "select <ident>;" or "return <ident>;"
- The last character of <ident> is a multi-byte character
- the last byte of this character is ';' '*', '/' or whitespace

In this case, the body of the object will be truncated after parsing,
and stored in an invalid format.

This last issue has not been fixed in this patch, since the real fix
will be implemented by Bug 25411 (trigger code truncated), which is caused
by the very same code.
The real problem is that the function skip_rear_comments is only a
work-around, and should be removed entirely: see the proposed patch for
bug 25411 for details.

into  vajra.(none):/opt/local/work/mysql-5.0-runtime

 Bug #23667 "CREATE TABLE LIKE is not isolated from alteration
             by other connections"
 Bug #18950 "CREATE TABLE LIKE does not obtain LOCK_open"
As well as:
 Bug #25578 "CREATE TABLE LIKE does not require any privileges
             on source table".

The first and the second bugs resulted in various errors and wrong
binary log order when one tried to execute concurrently CREATE TABLE LIKE
statement and DDL statements on source table or DML/DDL statements on its
target table.

The problem was caused by incomplete protection/table-locking against
concurrent statements implemented in mysql_create_like_table() routine.
We solve it by simply implementing such protection in proper way (see
comment for sql_table.cc for details).

The third bug allowed user who didn't have any privileges on table create
its copy and therefore circumvent privilege check for SHOW CREATE TABLE.

This patch solves this problem by adding privilege check, which was missing.

Finally it also removes some duplicated code from mysql_create_like_table().

Note that, altough tests covering concurrency-related aspects of CREATE TABLE
LIKE behaviour will only be introduced in 5.1, they were run manually for
this patch as well.

into  mysql.com:/home/svoj/devel/mysql/merge/mysql-5.0-engines

into  mysql.com:/home/svoj/devel/mysql/merge/mysql-5.0-engines

into  mysql.com:/home/svoj/devel/mysql/merge/mysql-4.1-engines

into  whalegate.ndb.mysql.com:/home/tomas/mysql-5.0-ndb

into  whalegate.ndb.mysql.com:/home/tomas/mysql-5.0-ndb

into  whalegate.ndb.mysql.com:/home/tomas/mysql-4.1-ndb

into  quadxeon.mysql.com:/benchmarks/ext3/TOSAVE/tsmith/bk/maint/50

into  quadxeon.mysql.com:/benchmarks/ext3/TOSAVE/tsmith/bk/maint/50

into  quadxeon.mysql.com:/benchmarks/ext3/TOSAVE/tsmith/bk/maint/41

into  whalegate.ndb.mysql.com:/home/tomas/mysql-5.0-ndb

into  whalegate.ndb.mysql.com:/home/tomas/mysql-5.0-ndb

into  whalegate.ndb.mysql.com:/home/tomas/mysql-4.1-ndb

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

 - The SQL commands used by mysql_upgrade are written to be run
    with sql_mode set to '' - thus the scripts should change sql_mode
    for the session to make sure the SQL is legal.

into  mysql.com:/d2/hf/mrg/mysql-5.0-opt

into  sergbook.mysql.com:/usr/home/serg/Abk/mysql-5.0

into  mysql.com:/d2/hf/mrg/mysql-5.0-opt

into  mysql.com:/d2/hf/mrg/mysql-5.0-opt

into  mysql.com:/d2/hf/mrg/mysql-4.1-opt

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

into  pilot.blaudden:/home/msvensson/mysql/mysql-4.1-maint

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

 - Final touchups

into  perch.ndb.mysql.com:/home/jonas/src/mysql-4.1-ndb

into  perch.ndb.mysql.com:/home/jonas/src/mysql-5.0-ndb

into  moonbone.local:/mnt/gentoo64/work/28261-bug-5.0-opt-mysql

into  perch.ndb.mysql.com:/home/jonas/src/50-work

  review comment 2, atleast 1 signal need for test prg

into  perch.ndb.mysql.com:/home/jonas/src/mysql-5.0-ndb

into  perch.ndb.mysql.com:/home/jonas/src/50-work

into  perch.ndb.mysql.com:/home/jonas/src/mysql-4.1-ndb

  review comment
  if some tcp-transporter has data, then do select with timeout 0

Adjust the check that defines the error message to be returned.

into  perch.ndb.mysql.com:/home/jonas/src/mysql-5.0-ndb

into  perch.ndb.mysql.com:/home/jonas/src/mysql-4.1-ndb

into  perch.ndb.mysql.com:/home/jonas/src/50-work