There actually were several problems here:
  - WRITE-lock is required to load events from the mysql.event table,
    but in the read-only mode an ordinary user can not acquire it;
  - Security_context::master_access attribute was not properly
    initialized in Security_context::init(), which led to differences
    in behavior with and without debug configure options.
  - if the server failed to load events from mysql.event, it forgot to
    close the mysql.event table, that led to the coredump, described
    in the bug report.

The patch is to fix all these problems:
  - Use the super-user to acquire WRITE-lock on the mysql.even table;
  - The WRITE-lock is acquired by the event scheduler in two cases:
    - on initial loading of events from the database;
    - when an event has been executed, so its attributes should
      be updated.
    Other cases when WRITE-lock is needed for the mysql.event table
    happen under the user account. So, nothing should be changed there
    for the read-only mode. The user is able to create/update/drop
    an event only if he is a super-user.
  - Initialize Security_context::master_access;
  - Close the mysql.event table in case something went wrong.

into  lambda.hsd1.co.comcast.net.:/home/malff/TREE/mysql-5.1-runtime

into  lambda.hsd1.co.comcast.net.:/home/malff/TREE/mysql-5.1-rt-merge

into  lambda.hsd1.co.comcast.net.:/home/malff/TREE/mysql-5.1-rt-merge

into  lambda.hsd1.co.comcast.net.:/home/malff/TREE/mysql-5.0-rt-merge

into  moksha.com.br:/Users/davi/mysql/mysql-5.1-runtime

into  moksha.com.br:/Users/davi/mysql/mysql-5.1-runtime

The general log write function (general_log_print) uses printf style
arguments which need to be pre-processed, meaning that the all arguments
are copied to a single buffer and the problem is that the buffer size is
constant (1022 characters) but queries can be much larger then this.

The solution is to introduce a new log write function that accepts a
buffer and it's length as arguments. The function is to be used when
a formatted output is not required, which is the case for almost all
query write-to-log calls.

This is a incompatible change with respect to the log format of prepared
statements.

into  damien-katzs-computer.local:/Users/dkatz/mysql-5.1-runtime

    
Previously, UDF *_init functions were passed constant strings with erroneous lengths. The length came from the containing variable's size, not the length of the value itself.
    
Now the *_init functions get the constant as a null terminated string with the correct length supplied too.

into  moksha.com.br:/Users/davi/mysql/mysql-5.1-runtime

Post merge fixes: close any open statement before
the change user command and fix test case output.

into  ramayana.hindu.god:/home/tsmith/m/bk/maint/51

in middle of block)

into  moksha.com.br:/Users/davi/mysql/mysql-5.1-runtime

The problem was that the RETURNS column in the mysql.proc was of
CHAR(64). That was not enough for storing long-named datatypes.

The fix is to change CHAR(64) to LONGBLOB, and to throw warnings
at the time a stored routine is created if some data is truncated
during writing into mysql.proc.

into  polly.(none):/home/kaa/src/maint/mysql-5.1-maint

into  polly.(none):/home/kaa/src/maint/mysql-5.0-maint

into  lambda.hsd1.co.comcast.net.:/home/malff/TREE/mysql-5.1-rt-merge

into  adventure.(none):/home/thek/Development/cpp/mysql-5.1-runtime

test programs.

into  lambda.hsd1.co.comcast.net.:/home/malff/TREE/mysql-5.0-28318-rework

(this is a backward-compatible change).

The problem is that currently there is no way to test the behavior
of the mysql_change_user() function using the mysqltest suite because
there is no internal command for it.

The solution is to introduce a change_user command that can be used
to test aspects of the MySQL client function mysql_change_user().

into  polly.(none):/home/kaa/src/maint/mysql-5.1-maint

into  polly.(none):/home/kaa/src/maint/mysql-5.0-maint

into  polly.(none):/home/kaa/src/maint/mysql-4.1-maint

into  adventure.(none):/home/thek/Development/cpp/mysql-5.1-runtime

The embedded version of the server doesn't use column level grants, and 
the compile directive NO_EMBEDDED_ACCESS_CHECKS should be checked instead of
the redundant HAVE_QUERY_CACHE (which is always the case) to determine if 
column level grants should be compiled or not.

The root cause of the issue was that the CREATE FUNCTION grammar,
for User Defined Functions, was using the sp_name rule.
The sp_name rule is intended for fully qualified stored procedure names,
like either ident.ident, or just ident but with a default database
implicitly selected.

A UDF does not have a fully qualified name, only a name (ident), and should
not use the sp_name grammar fragment during parsing.

The fix is to re-organize the CREATE FUNCTION grammar, to better separate:
- creating UDF (no definer, can have AGGREGATE, simple ident)
- creating Stored Functions (definer, no AGGREGATE, fully qualified name)

With the test case provided, another issue was exposed which is also fixed:
the DROP FUNCTION statement was using sp_name and also failing when no database
is implicitly selected, when droping UDF functions.
The fix is also to change the grammar so that DROP FUNCTION works with
both the ident.ident syntax (to drop a stored function), or just the ident
syntax (to drop either a UDF or a Stored Function, in the current database)

into  damien-katzs-computer.local:/Users/dkatz/mysql-5.1-runtime

into  damien-katzs-computer.local:/Users/dkatz/mysql-5.0-runtime

explicitly.