Merge pnousiainen@bk-internal.mysql.com:/home/bk/mysql-5.0

into  mysql.com:/space/pekka/ndb/version/my50

4 files changed, 193 insertions, 85 deletions

diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc
index c4c72910265..d2699b88aa4 100644
--- a/sql/sql_lex.cc
+++ b/sql/sql_lex.cc
@@ -151,8 +151,7 @@ void lex_start(THD *thd, uchar *buf,uint length)
   lex->found_semicolon= 0;
   lex->safe_to_cache_query= 1;
   lex->time_zone_tables_used= 0;
-  lex->leaf_tables_insert= lex->query_tables= 0;
-  lex->query_tables_last= &lex->query_tables;
+  lex->leaf_tables_insert= 0;
   lex->variables_used= 0;
   lex->empty_field_list_on_rset= 0;
   lex->select_lex.select_number= 1;
@@ -175,14 +174,9 @@ void lex_start(THD *thd, uchar *buf,uint length)
   lex->sphead= NULL;
   lex->spcont= NULL;
   lex->proc_list.first= 0;
-  lex->query_tables_own_last= 0;
   lex->escape_used= FALSE;
+  lex->reset_query_tables_list(FALSE);
 
-  if (lex->sroutines.records)
-    my_hash_reset(&lex->sroutines);
-  lex->sroutines_list.empty();
-  lex->sroutines_list_own_last= lex->sroutines_list.next;
-  lex->sroutines_list_own_elements= 0;
   lex->nest_level=0 ;
   lex->allow_sum_func= 0;
   lex->in_sum_func= NULL;
@@ -1615,6 +1609,52 @@ void st_select_lex::print_limit(THD *thd, String *str)
 
 
 /*
+  Initialize (or reset) Query_tables_list object.
+
+  SYNOPSIS
+    reset_query_tables_list()
+      init  TRUE  - we should perform full initialization of object with
+                    allocating needed memory
+            FALSE - object is already initialized so we should only reset
+                    its state so it can be used for parsing/processing
+                    of new statement
+
+  DESCRIPTION
+    This method initializes Query_tables_list so it can be used as part
+    of LEX object for parsing/processing of statement. One can also use
+    this method to reset state of already initialized Query_tables_list
+    so it can be used for processing of new statement.
+*/
+
+void Query_tables_list::reset_query_tables_list(bool init)
+{
+  query_tables= 0;
+  query_tables_last= &query_tables;
+  query_tables_own_last= 0;
+  if (init)
+    hash_init(&sroutines, system_charset_info, 0, 0, 0, sp_sroutine_key, 0, 0);
+  else if (sroutines.records)
+    my_hash_reset(&sroutines);
+  sroutines_list.empty();
+  sroutines_list_own_last= sroutines_list.next;
+  sroutines_list_own_elements= 0;
+}
+
+
+/*
+  Destroy Query_tables_list object with freeing all resources used by it.
+
+  SYNOPSIS
+    destroy_query_tables_list()
+*/
+
+void Query_tables_list::destroy_query_tables_list()
+{
+  hash_free(&sroutines);
+}
+
+
+/*
   Initialize LEX object.
 
   SYNOPSIS
@@ -1630,12 +1670,9 @@ void st_select_lex::print_limit(THD *thd, String *str)
 
 st_lex::st_lex()
   :result(0), yacc_yyss(0), yacc_yyvs(0),
-   sql_command(SQLCOM_END), query_tables_own_last(0)
+   sql_command(SQLCOM_END)
 {
-  hash_init(&sroutines, system_charset_info, 0, 0, 0, sp_sroutine_key, 0, 0);
-  sroutines_list.empty();
-  sroutines_list_own_last= sroutines_list.next;
-  sroutines_list_own_elements= 0;
+  reset_query_tables_list(TRUE);
 }
 
 
@@ -2019,6 +2056,11 @@ void st_lex::link_first_table_back(TABLE_LIST *first,
 
   SYNOPSIS
     st_lex::cleanup_after_one_table_open()
+
+  NOTE
+    This method is mostly responsible for cleaning up of selects lists and
+    derived tables state. To rollback changes in Query_tables_list one has
+    to call Query_tables_list::reset_query_tables_list(FALSE).
 */
 
 void st_lex::cleanup_after_one_table_open()
@@ -2045,11 +2087,41 @@ void st_lex::cleanup_after_one_table_open()
     select_lex.cut_subtree();
   }
   time_zone_tables_used= 0;
-  if (sroutines.records)
-    my_hash_reset(&sroutines);
-  sroutines_list.empty();
-  sroutines_list_own_last= sroutines_list.next;
-  sroutines_list_own_elements= 0;
+}
+
+
+/*
+  Save current state of Query_tables_list for this LEX, and prepare it
+  for processing of new statemnt.
+
+  SYNOPSIS
+    reset_n_backup_query_tables_list()
+      backup  Pointer to Query_tables_list instance to be used for backup
+*/
+
+void st_lex::reset_n_backup_query_tables_list(Query_tables_list *backup)
+{
+  backup->set_query_tables_list(this);
+  /*
+    We have to perform full initialization here since otherwise we
+    will damage backed up state.
+  */
+  this->reset_query_tables_list(TRUE);
+}
+
+
+/*
+  Restore state of Query_tables_list for this LEX from backup.
+
+  SYNOPSIS
+    restore_backup_query_tables_list()
+      backup  Pointer to Query_tables_list instance used for backup
+*/
+
+void st_lex::restore_backup_query_tables_list(Query_tables_list *backup)
+{
+  this->destroy_query_tables_list();
+  this->set_query_tables_list(backup);
 }
 
 
diff --git a/sql/sql_lex.h b/sql/sql_lex.h
index 34e7ee969b6..6b5c6ddca60 100644
--- a/sql/sql_lex.h
+++ b/sql/sql_lex.h
@@ -702,9 +702,95 @@ extern sys_var_long_ptr trg_new_row_fake_var;
 enum xa_option_words {XA_NONE, XA_JOIN, XA_RESUME, XA_ONE_PHASE,
                       XA_SUSPEND, XA_FOR_MIGRATE};
 
+
+/*
+  Class representing list of all tables used by statement.
+  It also contains information about stored functions used by statement
+  since during its execution we may have to add all tables used by its
+  stored functions/triggers to this list in order to pre-open and lock
+  them.
+
+  Also used by st_lex::reset_n_backup/restore_backup_query_tables_list()
+  methods to save and restore this information.
+*/
+
+class Query_tables_list
+{
+public:
+  /* Global list of all tables used by this statement */
+  TABLE_LIST *query_tables;
+  /* Pointer to next_global member of last element in the previous list. */
+  TABLE_LIST **query_tables_last;
+  /*
+    If non-0 then indicates that query requires prelocking and points to
+    next_global member of last own element in query table list (i.e. last
+    table which was not added to it as part of preparation to prelocking).
+    0 - indicates that this query does not need prelocking.
+  */
+  TABLE_LIST **query_tables_own_last;
+  /* Set of stored routines called by statement. */
+  HASH sroutines;
+  /*
+    List linking elements of 'sroutines' set. Allows you to add new elements
+    to this set as you iterate through the list of existing elements.
+    'sroutines_list_own_last' is pointer to ::next member of last element of
+    this list which represents routine which is explicitly used by query.
+    'sroutines_list_own_elements' number of explicitly used routines.
+    We use these two members for restoring of 'sroutines_list' to the state
+    in which it was right after query parsing.
+  */
+  SQL_LIST sroutines_list;
+  byte     **sroutines_list_own_last;
+  uint     sroutines_list_own_elements;
+
+  /*
+    These constructor and destructor serve for creation/destruction
+    of Query_tables_list instances which are used as backup storage.
+  */
+  Query_tables_list() {}
+  ~Query_tables_list() {}
+
+  /* Initializes (or resets) Query_tables_list object for "real" use. */
+  void reset_query_tables_list(bool init);
+  void destroy_query_tables_list();
+  void set_query_tables_list(Query_tables_list *state)
+  {
+    *this= *state;
+  }
+
+  void add_to_query_tables(TABLE_LIST *table)
+  {
+    *(table->prev_global= query_tables_last)= table;
+    query_tables_last= &table->next_global;
+  }
+  bool requires_prelocking()
+  {
+    return test(query_tables_own_last);
+  }
+  void mark_as_requiring_prelocking(TABLE_LIST **tables_own_last)
+  {
+    query_tables_own_last= tables_own_last;
+  }
+  /* Return pointer to first not-own table in query-tables or 0 */
+  TABLE_LIST* first_not_own_table()
+  {
+    return ( query_tables_own_last ? *query_tables_own_last : 0);
+  }
+  void chop_off_not_own_tables()
+  {
+    if (query_tables_own_last)
+    {
+      *query_tables_own_last= 0;
+      query_tables_last= query_tables_own_last;
+      query_tables_own_last= 0;
+    }
+  }
+};
+
+
 /* The state of the lex parsing. This is saved in the THD struct */
 
-typedef struct st_lex
+typedef struct st_lex : public Query_tables_list
 {
   uint	 yylineno,yytoklen;			/* Simulate lex */
   LEX_YYSTYPE yylval;
@@ -736,14 +822,6 @@ typedef struct st_lex
   gptr yacc_yyss,yacc_yyvs;
   THD *thd;
   CHARSET_INFO *charset;
-  TABLE_LIST *query_tables;	/* global list of all tables in this query */
-  /*
-    last element next_global of previous list (used only for list building
-    during parsing and VIEW processing. This pointer could be invalid during
-    processing of information schema tables(see get_schema_tables_result
-    function)
-  */
-  TABLE_LIST **query_tables_last;
   /* store original leaf_tables for INSERT SELECT and PS/SP */
   TABLE_LIST *leaf_tables_insert;
   /* Position (first character index) of SELECT of CREATE VIEW statement */
@@ -876,20 +954,6 @@ typedef struct st_lex
   bool sp_lex_in_use;	/* Keep track on lex usage in SPs for error handling */
   bool all_privileges;
   sp_pcontext *spcont;
-  /* Set of stored routines called by statement. */
-  HASH sroutines;
-  /*
-    List linking elements of 'sroutines' set. Allows you to add new elements
-    to this set as you iterate through the list of existing elements.
-    'sroutines_list_own_last' is pointer to ::next member of last element of
-    this list which represents routine which is explicitly used by query.
-    'sroutines_list_own_elements' number of explicitly used routines.
-    We use these two members for restoring of 'sroutines_list' to the state
-    in which it was right after query parsing.
-  */
-  SQL_LIST sroutines_list;
-  byte     **sroutines_list_own_last;
-  uint     sroutines_list_own_elements;
 
   st_sp_chistics sp_chistics;
   bool only_view;       /* used for SHOW CREATE TABLE/VIEW */
@@ -926,14 +990,6 @@ typedef struct st_lex
   const char *stmt_definition_begin;
 
   /*
-    If non-0 then indicates that query requires prelocking and points to
-    next_global member of last own element in query table list (i.e. last
-    table which was not added to it as part of preparation to prelocking).
-    0 - indicates that this query does not need prelocking.
-  */
-  TABLE_LIST **query_tables_own_last;
-
-  /*
     Pointers to part of LOAD DATA statement that should be rewritten
     during replication ("LOCAL 'filename' REPLACE INTO" part).
   */
@@ -945,7 +1001,7 @@ typedef struct st_lex
 
   virtual ~st_lex()
   {
-    hash_free(&sroutines);
+    destroy_query_tables_list();
   }
 
   inline void uncacheable(uint8 cause)
@@ -970,11 +1026,6 @@ typedef struct st_lex
   TABLE_LIST *unlink_first_table(bool *link_to_local);
   void link_first_table_back(TABLE_LIST *first, bool link_to_local);
   void first_lists_tables_same();
-  inline void add_to_query_tables(TABLE_LIST *table)
-  {
-    *(table->prev_global= query_tables_last)= table;
-    query_tables_last= &table->next_global;
-  }
   bool add_time_zone_tables_to_query_tables(THD *thd);
 
   bool can_be_merged();
@@ -1006,28 +1057,7 @@ typedef struct st_lex
       return FALSE;
     }
   }
-  inline bool requires_prelocking()
-  {
-    return test(query_tables_own_last);
-  }
-  inline void mark_as_requiring_prelocking(TABLE_LIST **tables_own_last)
-  {
-    query_tables_own_last= tables_own_last;
-  }
-  /* Return pointer to first not-own table in query-tables or 0 */
-  TABLE_LIST* first_not_own_table()
-  {
-    return ( query_tables_own_last ? *query_tables_own_last : 0);
-  }
-  void chop_off_not_own_tables()
-  {
-    if (query_tables_own_last)
-    {
-      *query_tables_own_last= 0;
-      query_tables_last= query_tables_own_last;
-      query_tables_own_last= 0;
-    }
-  }
+
   void cleanup_after_one_table_open();
 
   bool push_context(Name_resolution_context *context)
@@ -1044,6 +1074,9 @@ typedef struct st_lex
   {
     return context_stack.head();
   }
+
+  void reset_n_backup_query_tables_list(Query_tables_list *backup);
+  void restore_backup_query_tables_list(Query_tables_list *backup);
 } LEX;
 
 struct st_lex_local: public st_lex
diff --git a/sql/sql_show.cc b/sql/sql_show.cc
index 9018b364ec9..246da4dfeec 100644
--- a/sql/sql_show.cc
+++ b/sql/sql_show.cc
@@ -2065,7 +2065,6 @@ 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;
@@ -2084,6 +2083,7 @@ int get_all_tables(THD *thd, TABLE_LIST *tables, COND *cond)
   db_type not_used;
   Open_tables_state open_tables_state_backup;
   bool save_view_prepare_mode= lex->view_prepare_mode;
+  Query_tables_list query_tables_list_backup;
   lex->view_prepare_mode= TRUE;
   DBUG_ENTER("get_all_tables");
 
@@ -2096,6 +2096,8 @@ int get_all_tables(THD *thd, TABLE_LIST *tables, COND *cond)
   */
   lex->sql_command= SQLCOM_SHOW_FIELDS;
 
+  lex->reset_n_backup_query_tables_list(&query_tables_list_backup);
+
   /*
     We should not introduce deadlocks even if we already have some
     tables open and locked, since we won't lock tables which we will
@@ -2136,8 +2138,7 @@ int get_all_tables(THD *thd, TABLE_LIST *tables, COND *cond)
                                              show_table_list->db),
                                             show_table_list->alias));
     thd->temporary_tables= 0;
-    close_thread_tables(thd);
-    show_table_list->table= 0;
+    close_tables_for_reopen(thd, &show_table_list);
     goto err;
   }
 
@@ -2248,9 +2249,10 @@ int get_all_tables(THD *thd, TABLE_LIST *tables, COND *cond)
               in this case.
             */
             res= schema_table->process_table(thd, show_table_list, table,
-                                            res, base_name,
-                                            show_table_list->alias);
-            close_thread_tables(thd);
+                                             res, base_name,
+                                             show_table_list->alias);
+            close_tables_for_reopen(thd, &show_table_list);
+            DBUG_ASSERT(!lex->query_tables_own_last);
             if (res)
               goto err;
           }
@@ -2267,11 +2269,10 @@ 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->restore_backup_query_tables_list(&query_tables_list_backup);
   lex->derived_tables= derived_tables;
   lex->all_selects_list= old_all_select_lex;
-  lex->query_tables_last= save_query_tables_last;
   lex->view_prepare_mode= save_view_prepare_mode;
-  *save_query_tables_last= 0;
   lex->sql_command= save_sql_command;
   DBUG_RETURN(error);
 }
diff --git a/sql/sql_table.cc b/sql/sql_table.cc
index 476d5536581..9ec8e8db1fb 100644
--- a/sql/sql_table.cc
+++ b/sql/sql_table.cc
@@ -2240,6 +2240,7 @@ static bool mysql_admin_table(THD* thd, TABLE_LIST* tables,
         tables can be left opening
       */
       close_thread_tables(thd);
+      lex->reset_query_tables_list(FALSE);
       if (protocol->write())
 	goto err;
       continue;
@@ -2487,6 +2488,7 @@ send_result_message:
       }
     }
     close_thread_tables(thd);
+    lex->reset_query_tables_list(FALSE);
     table->table=0;				// For query cache
     if (protocol->write())
       goto err;