Fix for bug #10055 "Using stored function with information_schema causes empty

result set".

To enable full access to contents of I_S tables from stored functions
or statements that use them, we manipulate with thread's open tables
state and ensure that we won't cause deadlock when we open tables by
ignoring flushes and name-locks.
Building of contents of I_S.TABLES no longer requires locking of tables
since we use use handler::info() method with HA_STATUS_AUTO flag instead
of handler::update_auto_increment() for obtaining information about
auto-increment values. But this also means that handlers have to implement
support for HA_STATUS_AUTO flag (particularly InnoDB needs it).


mysql-test/r/alter_table.result:
  Updated test results. This change was caused by the fact that now when
  we build contents of I_S tables (and thus output of SHOW INDEX) we
  don't use instances of tables which may be already opened and locked
  by thread (we always use new instance).
mysql-test/r/information_schema.result:
  Added test which checks how information about current auto-increment value for
  table is reported in INFORMATION_SCHEMA.TABLES view.
mysql-test/r/sp.result:
  Added test for bug #10055 "Using stored function with information_schema causes
  empty result set".
mysql-test/t/information_schema.test:
  Added test which checks how information about current auto-increment value for
  table is reported in INFORMATION_SCHEMA.TABLES view.
mysql-test/t/sp.test:
  Added test for bug #10055 "Using stored function with information_schema causes
  empty result set".
sql/mysql_priv.h:
  close_thread_tables():
    Get rid of 'stopper' argument which is no longer used. Now when we need
    to open and then close some table without touching tables which are already
    opened we use THD::reset_n/restore_backup_open_tables_state() methods.
  open_tables()/open_normal_and_derived_tables():
    Added 'flags' argument to be able open tables even if some has done
    a flush or hold namelock on them.
sql/sp.cc:
  close_proc_table/open_proc_table_for_read/db_find_routine():
    Replaced push_open_tables_state/pop_open_tables_state() methods which
    were saving/restoring current open tables state in/from THD::open_state_list
    with reset_n_backup_open_tables_state/restore_backup_open_tables_state()
    methods which assume that backup storage for this state is allocated on
    stack (or elsewhere) by their caller.
  open_proc_table_for_read():
    Since now we can have several open tables states stacked up we can't rely
    rely on checking whether we have some tables open in previous state.
    Instead we always assume that some tables are open and we need to ignore
    flush while locking mysql.proc. We don't really need 
    MYSQL_LOCK_IGNORE_GLOBAL_READ_LOCK in this case since we open mysql.proc table
    only for reading.
sql/sp.h:
  Added declarations of open_proc_table_for_read()/close_proc_table() to be
  able to use them in sql_show.cc.
sql/sql_base.cc:
  close_thread_tables():
    Get rid of 'stopper' argument which is no longer used. Now when we need
    to open and then close some table without touching tables which are already
    opened we use THD::reset_n/restore_backup_open_tables_state() methods.
  open_tables()/open_normal_and_derived_tables():
    Added 'flags' argument to be able open tables even if some has done
    a flush or hold namelock on them.
sql/sql_class.cc:
  Open_tables_state, THD:
    Replaced push_open_tables_state/pop_open_tables_state() methods which
    were saving/restoring current open tables state in/from THD::open_state_list
    with reset_n_backup_open_tables_state/restore_backup_open_tables_state()
    methods which assume that backup storage for this state is allocated on
    stack (or elsewhere) by their caller.
sql/sql_class.h:
  Open_tables_state, THD:
    Replaced push_open_tables_state/pop_open_tables_state() methods which
    were saving/restoring current open tables state in/from THD::open_state_list
    with reset_n_backup_open_tables_state/restore_backup_open_tables_state()
    methods which assume that backup storage for this state is allocated on
    stack (or elsewhere) by their caller.
sql/sql_handler.cc:
  open_tables()/open_normal_and_derived_tables():
    Added 'flags' argument to be able open tables even if some has done
    a flush or hold namelock on them.
sql/sql_prepare.cc:
  open_tables()/open_normal_and_derived_tables():
    Added 'flags' argument to be able open tables even if some has done
    a flush or hold namelock on them.
sql/sql_show.cc:
  get_all_tables():
    Now we use THD::reset_n_/restore_backup_open_tables_state() for 
    saving/restoring open tables state instead of working with it directly
    (This also allows us to have proper content of I_S system tables in
    statements with stored functions and in stored functions). We also
    ignore possible flushes when opening tables (we may create deadlock
    otherwise). Also we do all needed manipulations with LEX in this function
    and not in get_schema_tables_result() now.
  get_schema_tables_record():
    Let us use handler::info() method with HA_STATUS_AUTO flag for obtaining
    information about table's auto-increment value. This allows to avoid locking
    of tables which is needed when we use handler::update_auto_increment() method.
  fill_schema_proc():
    Now we use open_proc_table_for_read/close_proc_table() for access to
    mysql.proc table (so we won't cause deadlock if we already have some
    tables open and locked, this also allows us to have proper content in
    ROUTINES system table in statements using stored functions/in stored
    functions).
  get_schema_tables_result():
    Moved all manipulations with Open_tables_state and LEX needed for
    safe opening of tables to ST_SCHEMA_TABLE::fill_table functions
    (i.e. get_all_tables() and fill_schema_proc()).
sql/sql_update.cc:
  open_tables()/open_normal_and_derived_tables():
    Added 'flags' argument to be able open tables even if some has done
    a flush or hold namelock on them.

mysql-test/r/alter_table.result

@@ -314,7 +314,7 @@ INSERT INTO t1 VALUES ('localhost','root'),('localhost',''),('games','monty');
 SHOW INDEX FROM t1;
 Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment
 t1	0	PRIMARY	1	Host	A	NULL	NULL	NULL		BTREE	
-t1	0	PRIMARY	2	User	A	3	NULL	NULL		BTREE	
+t1	0	PRIMARY	2	User	A	0	NULL	NULL		BTREE	
 ALTER TABLE t1 ENABLE KEYS;
 UNLOCK TABLES;
 CHECK TABLES t1;
@@ -338,7 +338,7 @@ INSERT INTO t1 VALUES ('localhost','root'),('localhost','');
 SHOW INDEX FROM t1;
 Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment
 t1	0	PRIMARY	1	Host	A	NULL	NULL	NULL		BTREE	
-t1	0	PRIMARY	2	User	A	2	NULL	NULL		BTREE	
+t1	0	PRIMARY	2	User	A	0	NULL	NULL		BTREE	
 t1	1	Host	1	Host	A	NULL	NULL	NULL		BTREE	disabled
 ALTER TABLE t1 ENABLE KEYS;
 SHOW INDEX FROM t1;

mysql-test/r/information_schema.result

-DROP TABLE IF EXISTS t0,t1,t2;
+DROP TABLE IF EXISTS t0,t1,t2,t3,t5;
 show variables where variable_name like "skip_show_database";
 Variable_name	Value
 skip_show_database	OFF
@@ -30,6 +30,8 @@ create table mysqltest.t1(a int, b VARCHAR(30), KEY string_data (b));
 create table test.t2(a int);
 create table t3(a int, KEY a_data (a));
 create table mysqltest.t4(a int);
+create table t5 (id int auto_increment primary key);
+insert into t5 values (10);
 create view v1 (c) as select table_name from information_schema.TABLES;
 select * from v1;
 c
@@ -69,6 +71,7 @@ t1
 t4
 t2
 t3
+t5
 v1
 select c,table_name from v1 
 inner join information_schema.TABLES v2 on (v1.c=v2.table_name)
@@ -87,6 +90,7 @@ t1	t1
 t4	t4
 t2	t2
 t3	t3
+t5	t5
 select c,table_name from v1 
 left join information_schema.TABLES v2 on (v1.c=v2.table_name)
 where v1.c like "t%";
@@ -104,6 +108,7 @@ t1	t1
 t4	t4
 t2	t2
 t3	t3
+t5	t5
 select c, v2.table_name from v1
 right join information_schema.TABLES v2 on (v1.c=v2.table_name)
 where v1.c like "t%";
@@ -121,6 +126,7 @@ t1	t1
 t4	t4
 t2	t2
 t3	t3
+t5	t5
 select table_name from information_schema.TABLES
 where table_schema = "mysqltest" and table_name like "t%";
 table_name
@@ -136,10 +142,12 @@ show tables like 't%';
 Tables_in_test (t%)
 t2
 t3
+t5
 show table status;
 Name	Engine	Version	Row_format	Rows	Avg_row_length	Data_length	Max_data_length	Index_length	Data_free	Auto_increment	Create_time	Update_time	Check_time	Collation	Checksum	Create_options	Comment
 t2	MyISAM	10	Fixed	0	0	0	#	1024	0	NULL	#	#	NULL	latin1_swedish_ci	NULL		
 t3	MyISAM	10	Fixed	0	0	0	#	1024	0	NULL	#	#	NULL	latin1_swedish_ci	NULL		
+t5	MyISAM	10	Fixed	1	7	7	#	2048	0	11	#	#	NULL	latin1_swedish_ci	NULL		
 v1	NULL	NULL	NULL	NULL	NULL	NULL	#	NULL	NULL	NULL	#	#	NULL	NULL	NULL	NULL	view
 show full columns from t3 like "a%";
 Field	Type	Collation	Null	Key	Default	Extra	Privileges	Comment
@@ -173,7 +181,7 @@ where table_schema = 'mysqltest' and table_name = 'v1';
 table_name	column_name	privileges
 v1	c	select
 drop view v1, mysqltest.v1;
-drop tables mysqltest.t4, mysqltest.t1, t2, t3;
+drop tables mysqltest.t4, mysqltest.t1, t2, t3, t5;
 drop database mysqltest;
 select * from information_schema.CHARACTER_SETS
 where CHARACTER_SET_NAME like 'latin1%';

mysql-test/r/sp.result

@@ -3062,4 +3062,13 @@ l
 drop procedure bug6063|
 drop procedure bug7088_1|
 drop procedure bug7088_2|
+drop function if exists bug10055|
+create function bug10055(v char(255)) returns char(255) return lower(v)|
+select t.column_name, bug10055(t.column_name)
+from information_schema.columns as t
+where t.table_schema = 'test' and t.table_name = 't1'|
+column_name	bug10055(t.column_name)
+id	id
+data	data
+drop function bug10055|
 drop table t1,t2;

mysql-test/t/information_schema.test

@@ -5,7 +5,7 @@
 # show databases
 
 --disable_warnings
-DROP TABLE IF EXISTS t0,t1,t2;
+DROP TABLE IF EXISTS t0,t1,t2,t3,t5;
 --enable_warnings
 
 
@@ -30,6 +30,8 @@ create table mysqltest.t1(a int, b VARCHAR(30), KEY string_data (b));
 create table test.t2(a int);
 create table t3(a int, KEY a_data (a));
 create table mysqltest.t4(a int);
+create table t5 (id int auto_increment primary key);
+insert into t5 values (10);
 create view v1 (c) as select table_name from information_schema.TABLES;
 select * from v1;
 
@@ -76,7 +78,7 @@ where table_schema = 'mysqltest' and table_name = 'v1';
 connection default;
 
 drop view v1, mysqltest.v1;
-drop tables mysqltest.t4, mysqltest.t1, t2, t3;
+drop tables mysqltest.t4, mysqltest.t1, t2, t3, t5;
 drop database mysqltest;
 
 # Test for information_schema.CHARACTER_SETS &

mysql-test/t/sp.test

@@ -3833,6 +3833,21 @@ drop procedure bug7088_1|
 drop procedure bug7088_2|
 
 
+#
+# Bug#10055 "Using stored function with information_schema causes empty
+#            result set"
+#
+--disable_warnings
+drop function if exists bug10055|
+--enable_warnings
+create function bug10055(v char(255)) returns char(255) return lower(v)|
+# This select should not crash server and should return all fields in t1
+select t.column_name, bug10055(t.column_name)
+from information_schema.columns as t
+where t.table_schema = 'test' and t.table_name = 't1'|
+drop function bug10055|
+
+
 #
 # BUG#NNNN: New bug synopsis
 #

sql/mysql_priv.h

@@ -482,8 +482,7 @@ typedef Comp_creator* (*chooser_compare_func_creator)(bool invert);
 void free_items(Item *item);
 void cleanup_items(Item *item);
 class THD;
-void close_thread_tables(THD *thd, bool locked=0, bool skip_derived=0,
-                         TABLE *stopper= 0);
+void close_thread_tables(THD *thd, bool locked=0, bool skip_derived=0);
 bool check_one_table_access(THD *thd, ulong privilege,
 			   TABLE_LIST *tables);
 bool check_routine_access(THD *thd,ulong want_access,char *db,char *name,
@@ -924,10 +923,10 @@ int setup_conds(THD *thd, TABLE_LIST *tables, TABLE_LIST *leaves,
 int setup_ftfuncs(SELECT_LEX* select);
 int init_ftfuncs(THD *thd, SELECT_LEX* select, bool no_order);
 void wait_for_refresh(THD *thd);
-int open_tables(THD *thd, TABLE_LIST **tables, uint *counter);
+int open_tables(THD *thd, TABLE_LIST **tables, uint *counter, uint flags);
 int simple_open_n_lock_tables(THD *thd,TABLE_LIST *tables);
 bool open_and_lock_tables(THD *thd,TABLE_LIST *tables);
-bool open_normal_and_derived_tables(THD *thd, TABLE_LIST *tables);
+bool open_normal_and_derived_tables(THD *thd, TABLE_LIST *tables, uint flags);
 int lock_tables(THD *thd, TABLE_LIST *tables, uint counter);
 TABLE *open_temporary_table(THD *thd, const char *path, const char *db,
 			    const char *table_name, bool link_in_list);

sql/sp.cc

@@ -69,12 +69,15 @@ bool mysql_proc_table_exists= 1;
   SYNOPSIS
     close_proc_table()
       thd     Thread context
+      backup  Pointer to Open_tables_state instance which holds
+              information about tables which were open before we
+              decided to access mysql.proc.
 */
 
-static void close_proc_table(THD *thd)
+void close_proc_table(THD *thd, Open_tables_state *backup)
 {
   close_thread_tables(thd);
-  thd->pop_open_tables_state();
+  thd->restore_backup_open_tables_state(backup);
 }
 
 
@@ -84,6 +87,9 @@ static void close_proc_table(THD *thd)
   SYNOPSIS
     open_proc_table_for_read()
       thd     Thread context
+      backup  Pointer to Open_tables_state instance where information about
+              currently open tables will be saved, and from which will be
+              restored when we will end work with mysql.proc.
 
   NOTES
     Thanks to restrictions which we put on opening and locking of
@@ -97,11 +103,10 @@ static void close_proc_table(THD *thd)
     #	Pointer to TABLE object of mysql.proc
 */
 
-static TABLE *open_proc_table_for_read(THD *thd)
+TABLE *open_proc_table_for_read(THD *thd, Open_tables_state *backup)
 {
   TABLE_LIST tables;
   TABLE *table;
-  bool old_open_tables= thd->open_tables != 0;
   bool refresh;
   DBUG_ENTER("open_proc_table");
 
@@ -112,8 +117,7 @@ static TABLE *open_proc_table_for_read(THD *thd)
   if (!mysql_proc_table_exists)
     DBUG_RETURN(0);
 
-  if (thd->push_open_tables_state())
-    DBUG_RETURN(0);
+  thd->reset_n_backup_open_tables_state(backup);
 
   bzero((char*) &tables, sizeof(tables));
   tables.db= (char*) "mysql";
@@ -121,7 +125,7 @@ static TABLE *open_proc_table_for_read(THD *thd)
   if (!(table= open_table(thd, &tables, thd->mem_root, &refresh,
                           MYSQL_LOCK_IGNORE_FLUSH)))
   {
-    thd->pop_open_tables_state();
+    thd->restore_backup_open_tables_state(backup);
     mysql_proc_table_exists= 0;
     DBUG_RETURN(0);
   }
@@ -130,15 +134,13 @@ static TABLE *open_proc_table_for_read(THD *thd)
 
   table->reginfo.lock_type= TL_READ;
   /*
-    If we have other tables opened, we have to ensure we are not blocked
-    by a flush tables or global read lock, as this could lead to a deadlock
+    We have to ensure we are not blocked by a flush tables, as this
+    could lead to a deadlock if we have other tables opened.
   */
   if (!(thd->lock= mysql_lock_tables(thd, &table, 1,
-                                     old_open_tables ?
-                                     (MYSQL_LOCK_IGNORE_GLOBAL_READ_LOCK |
-                                      MYSQL_LOCK_IGNORE_FLUSH) : 0)))
+                                     MYSQL_LOCK_IGNORE_FLUSH)))
   {
-    close_proc_table(thd);
+    close_proc_table(thd, backup);
     DBUG_RETURN(0);
   }
   DBUG_RETURN(table);
@@ -271,12 +273,13 @@ db_find_routine(THD *thd, int type, sp_name *name, sp_head **sphp)
   char buff[65];
   String str(buff, sizeof(buff), &my_charset_bin);
   ulong sql_mode;
+  Open_tables_state open_tables_state_backup;
   DBUG_ENTER("db_find_routine");
   DBUG_PRINT("enter", ("type: %d name: %*s",
 		       type, name->m_name.length, name->m_name.str));
 
   *sphp= 0;                                     // In case of errors
-  if (!(table= open_proc_table_for_read(thd)))
+  if (!(table= open_proc_table_for_read(thd, &open_tables_state_backup)))
     DBUG_RETURN(SP_OPEN_TABLE_FAILED);
 
   if ((ret= db_find_routine_aux(thd, type, name, table)) != SP_OK)
@@ -371,7 +374,7 @@ db_find_routine(THD *thd, int type, sp_name *name, sp_head **sphp)
   chistics.comment.str= ptr;
   chistics.comment.length= length;
 
-  close_proc_table(thd);
+  close_proc_table(thd, &open_tables_state_backup);
   table= 0;
 
   {
@@ -449,7 +452,7 @@ db_find_routine(THD *thd, int type, sp_name *name, sp_head **sphp)
 
  done:
   if (table)
-    close_proc_table(thd);
+    close_proc_table(thd, &open_tables_state_backup);
   DBUG_RETURN(ret);
 }
 

sql/sp.h

@@ -90,6 +90,13 @@ void sp_cache_routines_and_add_tables_for_triggers(THD *thd, LEX *lex,
 
 extern "C" byte* sp_sroutine_key(const byte *ptr, uint *plen, my_bool first);
 
+/*
+  Routines which allow open/lock and close mysql.proc table even when
+  we already have some tables open and locked.
+*/
+TABLE *open_proc_table_for_read(THD *thd, Open_tables_state *backup);
+void close_proc_table(THD *thd, Open_tables_state *backup);
+
 //
 // Utilities...
 //

sql/sql_base.cc

@@ -401,8 +401,7 @@ static void mark_used_tables_as_free_for_reuse(THD *thd, TABLE *table)
     upper level) and will leave prelocked mode if needed.
 */
 
-void close_thread_tables(THD *thd, bool lock_in_use, bool skip_derived, 
-                         TABLE *stopper)
+void close_thread_tables(THD *thd, bool lock_in_use, bool skip_derived)
 {
   bool found_old_table;
   prelocked_mode_type prelocked_mode= thd->prelocked_mode;
@@ -508,7 +507,7 @@ void close_thread_tables(THD *thd, bool lock_in_use, bool skip_derived,
   DBUG_PRINT("info", ("thd->open_tables: %p", thd->open_tables));
 
  found_old_table= 0;
-  while (thd->open_tables != stopper)
+  while (thd->open_tables)
     found_old_table|=close_thread_table(thd, &thd->open_tables);
   thd->some_tables_deleted=0;
 
@@ -1771,6 +1770,9 @@ memory to write 'DELETE FROM `%s`.`%s`' to the binary log",db,name);
     thd - thread handler
     start - list of tables in/out
     counter - number of opened tables will be return using this parameter
+    flags   - bitmap of flags to modify how the tables will be open:
+              MYSQL_LOCK_IGNORE_FLUSH - open table even if someone has
+              done a flush or namelock on it.
 
   NOTE
     Unless we are already in prelocked mode, this function will also precache
@@ -1788,7 +1790,7 @@ memory to write 'DELETE FROM `%s`.`%s`' to the binary log",db,name);
     -1 - error
 */
 
-int open_tables(THD *thd, TABLE_LIST **start, uint *counter)
+int open_tables(THD *thd, TABLE_LIST **start, uint *counter, uint flags)
 {
   TABLE_LIST *tables;
   bool refresh;
@@ -1863,7 +1865,7 @@ int open_tables(THD *thd, TABLE_LIST **start, uint *counter)
     }
     (*counter)++;
     if (!tables->table &&
-	!(tables->table= open_table(thd, tables, &new_frm_mem, &refresh, 0)))
+	!(tables->table= open_table(thd, tables, &new_frm_mem, &refresh, flags)))
     {
       free_root(&new_frm_mem, MYF(MY_KEEP_PREALLOC));
       if (tables->view)
@@ -2089,7 +2091,8 @@ int simple_open_n_lock_tables(THD *thd, TABLE_LIST *tables)
 {
   DBUG_ENTER("simple_open_n_lock_tables");
   uint counter;
-  if (open_tables(thd, &tables, &counter) || lock_tables(thd, tables, counter))
+  if (open_tables(thd, &tables, &counter, 0) ||
+      lock_tables(thd, tables, counter))
     DBUG_RETURN(-1);				/* purecov: inspected */
   DBUG_RETURN(0);
 }
@@ -2116,7 +2119,7 @@ bool open_and_lock_tables(THD *thd, TABLE_LIST *tables)
 {
   uint counter;
   DBUG_ENTER("open_and_lock_tables");
-  if (open_tables(thd, &tables, &counter) ||
+  if (open_tables(thd, &tables, &counter, 0) ||
       lock_tables(thd, tables, counter) ||
       mysql_handle_derived(thd->lex, &mysql_derived_prepare) ||
       (thd->fill_derived_tables() &&
@@ -2133,6 +2136,9 @@ bool open_and_lock_tables(THD *thd, TABLE_LIST *tables)
     open_normal_and_derived_tables
     thd		- thread handler
     tables	- list of tables for open
+    flags       - bitmap of flags to modify how the tables will be open:
+                  MYSQL_LOCK_IGNORE_FLUSH - open table even if someone has
+                  done a flush or namelock on it.
 
   RETURN
     FALSE - ok
@@ -2143,12 +2149,12 @@ bool open_and_lock_tables(THD *thd, TABLE_LIST *tables)
     data from the tables.
 */
 
-bool open_normal_and_derived_tables(THD *thd, TABLE_LIST *tables)
+bool open_normal_and_derived_tables(THD *thd, TABLE_LIST *tables, uint flags)
 {
   uint counter;
   DBUG_ENTER("open_normal_and_derived_tables");
   DBUG_ASSERT(!thd->fill_derived_tables());
-  if (open_tables(thd, &tables, &counter) ||
+  if (open_tables(thd, &tables, &counter, flags) ||
       mysql_handle_derived(thd->lex, &mysql_derived_prepare))
     DBUG_RETURN(TRUE); /* purecov: inspected */
   DBUG_RETURN(0);

sql/sql_class.cc

@@ -157,8 +157,8 @@ bool foreign_key_prefix(Key *a, Key *b)
 ** Thread specific functions
 ****************************************************************************/
 
-Open_tables_state::Open_tables_state()
-  :version(refresh_version)
+Open_tables_state::Open_tables_state(ulong version_arg)
+  :version(version_arg)
 {
   reset_open_tables_state();
 }
@@ -172,7 +172,7 @@ Open_tables_state::Open_tables_state()
 
 THD::THD()
   :Statement(CONVENTIONAL_EXECUTION, 0, ALLOC_ROOT_MIN_BLOCK_SIZE, 0),
-   Open_tables_state(),
+   Open_tables_state(refresh_version),
    user_time(0), global_read_lock(0), is_fatal_error(0),
    rand_used(0), time_zone_used(0),
    last_insert_id_used(0), insert_id_used(0), clear_next_insert_id(0),
@@ -1789,31 +1789,26 @@ void THD::set_status_var_init()
   access to mysql.proc table to find definitions of stored routines.
 ****************************************************************************/
 
-bool THD::push_open_tables_state()
+void THD::reset_n_backup_open_tables_state(Open_tables_state *backup)
 {
-  Open_tables_state *state;
-  DBUG_ENTER("push_open_table_state");
-  /* Currently we only push things one level */
-  DBUG_ASSERT(open_state_list.elements == 0);
-
-  if (!(state= (Open_tables_state*) alloc(sizeof(*state))))
-    DBUG_RETURN(1);                             // Fatal error is set
-  /* Store state for currently open tables */
-  state->set_open_tables_state(this);
-  if (open_state_list.push_back(state, mem_root))
-    DBUG_RETURN(1);                             // Fatal error is set
+  DBUG_ENTER("reset_n_backup_open_tables_state");
+  backup->set_open_tables_state(this);
   reset_open_tables_state();
-  DBUG_RETURN(0);
+  DBUG_VOID_RETURN;
 }
 
-void THD::pop_open_tables_state()
-{
-  Open_tables_state *state;
-  DBUG_ENTER("pop_open_table_state");
-  /* Currently we only push things one level */
-  DBUG_ASSERT(open_state_list.elements == 1);
 
-  state= open_state_list.pop();
-  set_open_tables_state(state);
+void THD::restore_backup_open_tables_state(Open_tables_state *backup)
+{
+  DBUG_ENTER("restore_backup_open_tables_state");
+  /*
+    Before we will throw away current open tables state we want
+    to be sure that it was properly cleaned up.
+  */
+  DBUG_ASSERT(open_tables == 0 && temporary_tables == 0 &&
+              handler_tables == 0 && derived_tables == 0 &&
+              lock == 0 && locked_tables == 0 &&
+              prelocked_mode == NON_PRELOCKED);
+  set_open_tables_state(backup);
   DBUG_VOID_RETURN;
 }

sql/sql_class.h

@@ -996,7 +996,13 @@ class Open_tables_state
   ulong	version;
   uint current_tablenr;
 
-  Open_tables_state();
+  /*
+    This constructor serves for creation of Open_tables_state instances
+    which are used as backup storage.
+  */
+  Open_tables_state() {};
+
+  Open_tables_state(ulong version_arg);
 
   void set_open_tables_state(Open_tables_state *state)
   {
@@ -1203,7 +1209,6 @@ class THD :public ilink,
   List	     <MYSQL_ERROR> warn_list;
   uint	     warn_count[(uint) MYSQL_ERROR::WARN_LEVEL_END];
   uint	     total_warn_count;
-  List	     <Open_tables_state> open_state_list;
   /*
     Id of current query. Statement can be reused to execute several queries
     query_id is global in context of the whole MySQL server.
@@ -1457,8 +1462,8 @@ class THD :public ilink,
              (variables.sql_mode & MODE_STRICT_ALL_TABLES)));
   }
   void set_status_var_init();
-  bool push_open_tables_state();
-  void pop_open_tables_state();
+  void reset_n_backup_open_tables_state(Open_tables_state *backup);
+  void restore_backup_open_tables_state(Open_tables_state *backup);
 };
 
 

sql/sql_handler.cc

@@ -187,7 +187,7 @@ bool mysql_ha_open(THD *thd, TABLE_LIST *tables, bool reopen)
 
   /* for now HANDLER can be used only for real TABLES */
   tables->required_type= FRMTYPE_TABLE;
-  error= open_tables(thd, &tables, &counter);
+  error= open_tables(thd, &tables, &counter, 0);
 
   HANDLER_TABLES_HACK(thd);
   if (error)

sql/sql_prepare.cc

@@ -925,7 +925,7 @@ static bool mysql_test_insert(Prepared_statement *stmt,
     If we would use locks, then we have to ensure we are not using
     TL_WRITE_DELAYED as having two such locks can cause table corruption.
   */
-  if (open_normal_and_derived_tables(thd, table_list))
+  if (open_normal_and_derived_tables(thd, table_list, 0))
     goto error;
 
   if ((values= its++))
@@ -1005,7 +1005,7 @@ static int mysql_test_update(Prepared_statement *stmt,
   if (update_precheck(thd, table_list))
     goto error;
 
-  if (open_tables(thd, &table_list, &table_count))
+  if (open_tables(thd, &table_list, &table_count, 0))
     goto error;
 
   if (table_list->multitable_view)

sql/sql_show.cc

@@ -20,6 +20,7 @@
 #include "mysql_priv.h"
 #include "sql_select.h"                         // For select_describe
 #include "repl_failsafe.h"
+#include "sp.h"
 #include "sp_head.h"
 #include <my_dir.h>
 
@@ -351,7 +352,7 @@ mysqld_show_create(THD *thd, TABLE_LIST *table_list)
   thd->lex->view_prepare_mode= TRUE;
 
   /* Only one table for now, but VIEW can involve several tables */
-  if (open_normal_and_derived_tables(thd, table_list))
+  if (open_normal_and_derived_tables(thd, table_list, 0))
   {
     DBUG_RETURN(TRUE);
   }
@@ -550,7 +551,7 @@ mysqld_list_fields(THD *thd, TABLE_LIST *table_list, const char *wild)
   DBUG_ENTER("mysqld_list_fields");
   DBUG_PRINT("enter",("table: %s",table_list->table_name));
 
-  if (open_normal_and_derived_tables(thd, table_list))
+  if (open_normal_and_derived_tables(thd, table_list, 0))
     DBUG_VOID_RETURN;
   table= table_list->table;
 
@@ -1934,6 +1935,8 @@ int get_all_tables(THD *thd, TABLE_LIST *tables, COND *cond)
   TABLE *table= tables->table;
   SELECT_LEX *select_lex= &lex->select_lex;
   SELECT_LEX *old_all_select_lex= lex->all_selects_list;
+  TABLE_LIST **save_query_tables_last= lex->query_tables_last;
+  enum_sql_command save_sql_command= lex->sql_command;
   SELECT_LEX *lsel= tables->schema_select_lex;
   ST_SCHEMA_TABLE *schema_table= tables->schema_table;
   SELECT_LEX sel;
@@ -1942,40 +1945,49 @@ int get_all_tables(THD *thd, TABLE_LIST *tables, COND *cond)
   uint len;
   bool with_i_schema;
   enum enum_schema_tables schema_table_idx;
-  thr_lock_type lock_type;
   List<char> bases;
   List_iterator_fast<char> it(bases);
   COND *partial_cond; 
   uint derived_tables= lex->derived_tables; 
   int error= 1;
+  Open_tables_state open_tables_state_backup;
   DBUG_ENTER("get_all_tables");
 
   LINT_INIT(end);
   LINT_INIT(len);
 
+  /*
+    Let us set fake sql_command so views won't try to merge
+    themselves into main statement.
+  */
+  lex->sql_command= SQLCOM_SHOW_FIELDS;
+
+  /*
+    We should not introduce deadlocks even if we already have some
+    tables open and locked, since we won't lock tables which we will
+    open and will ignore possible name-locks for these tables.
+  */
+  thd->reset_n_backup_open_tables_state(&open_tables_state_backup);
+
   if (lsel)
   {
-    TABLE *old_open_tables= thd->open_tables;
     TABLE_LIST *show_table_list= (TABLE_LIST*) lsel->table_list.first;
     bool res;
 
     lex->all_selects_list= lsel;
-    res= open_normal_and_derived_tables(thd, show_table_list);
+    res= open_normal_and_derived_tables(thd, show_table_list,
+                                        MYSQL_LOCK_IGNORE_FLUSH);
     if (schema_table->process_table(thd, show_table_list,
                                     table, res, show_table_list->db,
                                     show_table_list->alias))
       goto err;
-    close_thread_tables(thd, 0, 0, old_open_tables);
+    close_thread_tables(thd);
     show_table_list->table= 0;
     error= 0;
     goto err;
   }
 
   schema_table_idx= get_schema_table_idx(schema_table);
-  lock_type= TL_UNLOCK;
-
-  if (schema_table_idx == SCH_TABLES)
-    lock_type= TL_READ;
 
   if (make_db_list(thd, &bases, &idx_field_vals,
                    &with_i_schema, 0))
@@ -2058,19 +2070,18 @@ int get_all_tables(THD *thd, TABLE_LIST *tables, COND *cond)
           else
           {
             int res;
-            TABLE *old_open_tables= thd->open_tables;
             if (make_table_list(thd, &sel, base_name, file_name))
               goto err;
             TABLE_LIST *show_table_list= (TABLE_LIST*) sel.table_list.first;
-            show_table_list->lock_type= lock_type;
             lex->all_selects_list= &sel;
             lex->derived_tables= 0;
-            res= open_normal_and_derived_tables(thd, show_table_list);
+            res= open_normal_and_derived_tables(thd, show_table_list,
+                                                MYSQL_LOCK_IGNORE_FLUSH);
             if (schema_table->process_table(thd, show_table_list, table,
                                             res, base_name,
                                             show_table_list->alias))
               goto err;
-            close_thread_tables(thd, 0, 0, old_open_tables);
+            close_thread_tables(thd);
           }
         }
       }
@@ -2084,8 +2095,12 @@ int get_all_tables(THD *thd, TABLE_LIST *tables, COND *cond)
 
   error= 0;
 err:
+  thd->restore_backup_open_tables_state(&open_tables_state_backup);
   lex->derived_tables= derived_tables;
   lex->all_selects_list= old_all_select_lex;
+  lex->query_tables_last= save_query_tables_last;
+  *save_query_tables_last= 0;
+  lex->sql_command= save_sql_command;
   DBUG_RETURN(error);
 }
 
@@ -2190,7 +2205,8 @@ static int get_schema_tables_record(THD *thd, struct st_table_list *tables,
     TABLE_SHARE *share= show_table->s;
     handler *file= show_table->file;
 
-    file->info(HA_STATUS_VARIABLE | HA_STATUS_TIME | HA_STATUS_NO_LOCK);
+    file->info(HA_STATUS_VARIABLE | HA_STATUS_TIME | HA_STATUS_AUTO |
+               HA_STATUS_NO_LOCK);
     if (share->tmp_table == TMP_TABLE)
       table->field[3]->store("TEMPORARY", 9, cs);
     else
@@ -2246,13 +2262,8 @@ static int get_schema_tables_record(THD *thd, struct st_table_list *tables,
     table->field[12]->store((longlong) file->delete_length);
     if (show_table->found_next_number_field)
     {
-      show_table->next_number_field=show_table->found_next_number_field;
-      show_table->next_number_field->reset();
-      file->update_auto_increment();
-      table->field[13]->store((longlong) show_table->
-                              next_number_field->val_int());
+      table->field[13]->store((longlong) file->auto_increment_value);
       table->field[13]->set_notnull();
-      show_table->next_number_field=0;
     }
     if (file->create_time)
     {
@@ -2711,12 +2722,14 @@ int fill_schema_proc(THD *thd, TABLE_LIST *tables, COND *cond)
   TABLE_LIST proc_tables;
   const char *wild= thd->lex->wild ? thd->lex->wild->ptr() : NullS;
   int res= 0;
-  TABLE *table= tables->table, *old_open_tables= thd->open_tables;
+  TABLE *table= tables->table;
   bool full_access;
   char definer[HOSTNAME_LENGTH+USERNAME_LENGTH+2];
+  Open_tables_state open_tables_state_backup;
   DBUG_ENTER("fill_schema_proc");
 
   strxmov(definer, thd->priv_user, "@", thd->priv_host, NullS);
+  /* We use this TABLE_LIST instance only for checking of privileges. */
   bzero((char*) &proc_tables,sizeof(proc_tables));
   proc_tables.db= (char*) "mysql";
   proc_tables.db_length= 5;
@@ -2724,7 +2737,7 @@ int fill_schema_proc(THD *thd, TABLE_LIST *tables, COND *cond)
   proc_tables.table_name_length= 4;
   proc_tables.lock_type= TL_READ;
   full_access= !check_table_access(thd, SELECT_ACL, &proc_tables, 1);
-  if (!(proc_table= open_ltable(thd, &proc_tables, TL_READ)))
+  if (!(proc_table= open_proc_table_for_read(thd, &open_tables_state_backup)))
   {
     DBUG_RETURN(1);
   }
@@ -2750,7 +2763,7 @@ int fill_schema_proc(THD *thd, TABLE_LIST *tables, COND *cond)
 
 err:
   proc_table->file->ha_index_end();
-  close_thread_tables(thd, 0, 0, old_open_tables);
+  close_proc_table(thd, &open_tables_state_backup);
   DBUG_RETURN(res);
 }
 
@@ -3567,11 +3580,6 @@ bool get_schema_tables_result(JOIN *join)
     TABLE_LIST *table_list= tab->table->pos_in_table_list;
     if (table_list->schema_table && thd->fill_derived_tables())
     {
-      TABLE_LIST **query_tables_last= lex->query_tables_last;
-      TABLE *old_derived_tables= thd->derived_tables;
-      MYSQL_LOCK *sql_lock= thd->lock;
-      lex->sql_command= SQLCOM_SHOW_FIELDS;
-      DBUG_ASSERT(!*query_tables_last);
       if (&lex->unit != lex->current_select->master_unit()) // is subselect
       {
         table_list->table->file->extra(HA_EXTRA_RESET_STATE);
@@ -3582,16 +3590,9 @@ bool get_schema_tables_result(JOIN *join)
       else
         table_list->table->file->records= 0;
 
-      thd->derived_tables= 0;
-      thd->lock=0;
       if (table_list->schema_table->fill_table(thd, table_list,
                                                tab->select_cond))
         result= 1;
-      thd->lock= sql_lock;
-      lex->sql_command= SQLCOM_SELECT;
-      thd->derived_tables= old_derived_tables;
-      lex->query_tables_last= query_tables_last;
-      *query_tables_last= 0;
     }
   }
   thd->no_warnings_for_error= 0;

sql/sql_update.cc

@@ -138,7 +138,7 @@ int mysql_update(THD *thd,
 
   LINT_INIT(timestamp_query_id);
 
-  if (open_tables(thd, &table_list, &table_count))
+  if (open_tables(thd, &table_list, &table_count, 0))
     DBUG_RETURN(1);
 
   if (table_list->multitable_view)
@@ -632,7 +632,8 @@ bool mysql_multi_update_prepare(THD *thd)
   thd->lex->sql_command= SQLCOM_UPDATE_MULTI;
 
   /* open tables and create derived ones, but do not lock and fill them */
-  if ((original_multiupdate && open_tables(thd, &table_list, & table_count)) ||
+  if ((original_multiupdate &&
+       open_tables(thd, &table_list, &table_count, 0)) ||
       mysql_handle_derived(lex, &mysql_derived_prepare))
     DBUG_RETURN(TRUE);
   /*