A fix and test cases for

Bug#4968 "Stored procedure crash if cursor opened on altered table"
Bug#19733 "Repeated alter, or repeated create/drop, fails"
Bug#19182 "CREATE TABLE bar (m INT) SELECT n FROM foo; doesn't work from 
stored procedure."
Bug#6895 "Prepared Statements: ALTER TABLE DROP COLUMN does nothing"
Bug#22060 "ALTER TABLE x AUTO_INCREMENT=y in SP crashes server"

Test cases for bugs 4968, 19733, 6895 will be added in 5.0.

Re-execution of CREATE DATABASE, CREATE TABLE and ALTER TABLE 
statements in stored routines or as prepared statements caused
incorrect results (and crashes in versions prior to 5.0.25).
In 5.1 the problem occured only for CREATE DATABASE, CREATE TABLE
SELECT and CREATE TABLE with INDEX/DATA DIRECTOY options).

The problem of bugs 4968, 19733, 19282 and 6895 was that functions
mysql_prepare_table, mysql_create_table and mysql_alter_table were not
re-execution friendly: during their operation they used to modify contents
of LEX (members create_info, alter_info, key_list, create_list),
thus making the LEX unusable for the next execution.
In particular, these functions removed processed columns and keys from
create_list, key_list and drop_list. Search the code in sql_table.cc 
for drop_it.remove() and similar patterns to find evidence.

The fix is to supply to these functions a usable copy of each of the
above structures at every re-execution of an SQL statement. 

To simplify memory management, LEX::key_list and LEX::create_list
were added to LEX::alter_info, a fresh copy of which is created for
every execution.

The problem of crashing bug 22060 stemmed from the fact that the above 
metnioned functions were not only modifying HA_CREATE_INFO structure in 
LEX, but also were changing it to point to areas in volatile memory of 
the execution memory root.
 
The patch solves this problem by creating and using an on-stack
copy of HA_CREATE_INFO (note that code in 5.1 already creates and
uses a copy of this structure in mysql_create_table()/alter_table(),
but this approach didn't work well for CREATE TABLE SELECT statement).


mysql-test/r/ps.result:
  Update test results (Bug#19182, Bug#22060)
mysql-test/t/ps.test:
  Add a test case for Bug#19182, Bug#22060 (4.1-only parts)
sql/mysql_priv.h:
  LEX::key_list and LEX::create_list were moved to LEX::alter_info.
  Update declarations to use LEX::alter_info instead of these two
  members.
sql/sql_class.h:
  Replace pair<columns, keys> with an instance of Alter_info in
  select_create constructor. We create a new copy of Alter_info
  each time we re-execute SELECT .. CREATE prepared statement.
sql/sql_insert.cc:
  Adjust to a new signature of create_table_from_items.
sql/sql_lex.cc:
  Implement Alter_info::Alter_info that would make a "deep" copy
  of all definition lists (keys, columns).
sql/sql_lex.h:
  Move key_list and create_list to class Alter_info. Implement
  Alter_info::Alter_info that can be used with PS and SP.
sql/sql_list.h:
  Implement a copy constructor of class List that makes a deep copy
  of all list nodes.
sql/sql_parse.cc:
  Adjust to new signatures of mysql_create_table, mysql_alter_table,
  select_create. Functions mysql_create_index and mysql_drop_index has
  become identical after initialization of alter_info was moved to the 
  parser, and were merged. Flag enable_slow_log was not updated for 
  SQLCOM_DROP_INDEX, which is a bug. Just like CREATE INDEX, DROP INDEX
  is currently done via complete table rebuild and is rightfully a slow
  administrative statement.
sql/sql_show.cc:
  Adjust mysqld_show_create_db to a new signature.
sql/sql_table.cc:
  Adjust mysql_alter_table, mysql_recreate_table, mysql_create_table,
  mysql_prepare_table to new signatures.
sql/sql_yacc.yy:
  LEX::key_list and LEX::create_list moved to class Alter_info

1 files changed, 67 insertions, 0 deletions

diff --git a/mysql-test/r/ps.result b/mysql-test/r/ps.result
index 94c51fdc18b..0d6b01f3481 100644
--- a/mysql-test/r/ps.result
+++ b/mysql-test/r/ps.result
@@ -1035,4 +1035,71 @@ EXECUTE stmt USING @a;
 0	0
 DEALLOCATE PREPARE stmt;
 DROP TABLE t1;
+DROP TABLE IF EXISTS t1, t2;
+CREATE TABLE t1 (i INT);
+PREPARE st_19182
+FROM "CREATE TABLE t2 (i INT, j INT, KEY (i), KEY(j)) SELECT i FROM t1";
+EXECUTE st_19182;
+DESC t2;
+Field	Type	Null	Key	Default	Extra
+j	int(11)	YES	MUL	NULL	
+i	int(11)	YES	MUL	NULL	
+DROP TABLE t2;
+EXECUTE st_19182;
+DESC t2;
+Field	Type	Null	Key	Default	Extra
+j	int(11)	YES	MUL	NULL	
+i	int(11)	YES	MUL	NULL	
+DEALLOCATE PREPARE st_19182;
+DROP TABLE t2, t1;
+drop database if exists mysqltest;
+drop table if exists t1, t2;
+create database mysqltest character set utf8;
+prepare stmt1 from "create table mysqltest.t1 (c char(10))";
+prepare stmt2 from "create table mysqltest.t2 select 'test'";
+execute stmt1;
+execute stmt2;
+show create table mysqltest.t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `c` char(10) default NULL
+) ENGINE=MyISAM DEFAULT CHARSET=utf8
+show create table mysqltest.t2;
+Table	Create Table
+t2	CREATE TABLE `t2` (
+  `test` char(4) character set latin1 NOT NULL default ''
+) ENGINE=MyISAM DEFAULT CHARSET=utf8
+drop table mysqltest.t1;
+drop table mysqltest.t2;
+alter database mysqltest character set latin1;
+execute stmt1;
+execute stmt2;
+show create table mysqltest.t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `c` char(10) character set utf8 default NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+show create table mysqltest.t2;
+Table	Create Table
+t2	CREATE TABLE `t2` (
+  `test` char(4) NOT NULL default ''
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+drop database mysqltest;
+deallocate prepare stmt1;
+deallocate prepare stmt2;
+execute stmt;
+show create table t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `c` char(10) default NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1 DATA DIRECTORY='MYSQLTEST_VARDIR/tmp/'
+drop table t1;
+execute stmt;
+show create table t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `c` char(10) default NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1 DATA DIRECTORY='MYSQLTEST_VARDIR/tmp/'
+drop table t1;
+deallocate prepare stmt;
 End of 4.1 tests.