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			994 lines
		
	
	
		
			28 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			994 lines
		
	
	
		
			28 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
/* Copyright (C) 2000-2004 MySQL AB, 2008-2009 Sun Microsystems, Inc
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   This program is free software; you can redistribute it and/or modify
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   it under the terms of the GNU General Public License as published by
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   the Free Software Foundation; version 2 of the License.
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   This program is distributed in the hope that it will be useful,
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   but WITHOUT ANY WARRANTY; without even the implied warranty of
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   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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   GNU General Public License for more details.
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   You should have received a copy of the GNU General Public License
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   along with this program; if not, write to the Free Software
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   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
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/* HANDLER ... commands - direct access to ISAM */
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/* TODO:
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  HANDLER blabla OPEN [ AS foobar ] [ (column-list) ]
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  the most natural (easiest, fastest) way to do it is to
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  compute List<Item> field_list not in mysql_ha_read
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  but in mysql_ha_open, and then store it in TABLE structure.
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  The problem here is that mysql_parse calls free_item to free all the
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  items allocated at the end of every query. The workaround would to
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  keep two item lists per THD - normal free_list and handler_items.
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  The second is to be freeed only on thread end. mysql_ha_open should
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  then do { handler_items=concat(handler_items, free_list); free_list=0; }
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  But !!! do_command calls free_root at the end of every query and frees up
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  all the sql_alloc'ed memory. It's harder to work around...
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*/
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/*
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  The information about open HANDLER objects is stored in a HASH.
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  It holds objects of type TABLE_LIST, which are indexed by table
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  name/alias, and allows us to quickly find a HANDLER table for any
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  operation at hand - be it HANDLER READ or HANDLER CLOSE.
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  It also allows us to maintain an "open" HANDLER even in cases
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  when there is no physically open cursor. E.g. a FLUSH TABLE
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  statement in this or some other connection demands that all open
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  HANDLERs against the flushed table are closed. In order to
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  preserve the information about an open HANDLER, we don't perform
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  a complete HANDLER CLOSE, but only close the TABLE object.  The
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  corresponding TABLE_LIST is kept in the cache with 'table'
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  pointer set to NULL. The table will be reopened on next access
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  (this, however, leads to loss of cursor position, unless the
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  cursor points at the first record).
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*/
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#include "sql_priv.h"
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#include "sql_handler.h"
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#include "unireg.h"                    // REQUIRED: for other includes
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#include "sql_base.h"                           // close_thread_tables
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#include "lock.h"            // broadcast_refresh, mysql_unlock_tables
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#include "key.h"                                // key_copy
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#include "sql_base.h"                           // insert_fields
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#include "sql_select.h"
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#include "transaction.h"
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#define HANDLER_TABLES_HASH_SIZE 120
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static enum enum_ha_read_modes rkey_to_rnext[]=
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{ RNEXT_SAME, RNEXT, RPREV, RNEXT, RPREV, RNEXT, RPREV, RPREV };
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/*
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  Get hash key and hash key length.
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  SYNOPSIS
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    mysql_ha_hash_get_key()
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    tables                      Pointer to the hash object.
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    key_len_p   (out)           Pointer to the result for key length.
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    first                       Unused.
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  DESCRIPTION
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    The hash object is an TABLE_LIST struct.
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    The hash key is the alias name.
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    The hash key length is the alias name length plus one for the
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    terminateing NUL character.
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  RETURN
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    Pointer to the TABLE_LIST struct.
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*/
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static char *mysql_ha_hash_get_key(TABLE_LIST *tables, size_t *key_len_p,
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                                   my_bool first __attribute__((unused)))
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{
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  *key_len_p= strlen(tables->alias) + 1 ; /* include '\0' in comparisons */
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  return tables->alias;
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}
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/*
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  Free an hash object.
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  SYNOPSIS
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    mysql_ha_hash_free()
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    tables                      Pointer to the hash object.
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  DESCRIPTION
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    The hash object is an TABLE_LIST struct.
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  RETURN
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    Nothing
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*/
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static void mysql_ha_hash_free(TABLE_LIST *tables)
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{
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  my_free(tables);
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}
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/**
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  Close a HANDLER table.
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  @param thd Thread identifier.
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  @param tables A list of tables with the first entry to close.
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  @note Though this function takes a list of tables, only the first list entry
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  will be closed.
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  @note Broadcasts refresh if it closed a table with old version.
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*/
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static void mysql_ha_close_table(THD *thd, TABLE_LIST *tables)
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{
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  if (tables->table && !tables->table->s->tmp_table)
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  {
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    /* Non temporary table. */
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    tables->table->file->ha_index_or_rnd_end();
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    tables->table->open_by_handler= 0;
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    if (close_thread_table(thd, &tables->table))
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    {
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      /* Tell threads waiting for refresh that something has happened */
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      broadcast_refresh();
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    }
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    thd->mdl_context.release_lock(tables->mdl_request.ticket);
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  }
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  else if (tables->table)
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  {
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    /* Must be a temporary table */
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    TABLE *table= tables->table;
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    table->file->ha_index_or_rnd_end();
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    table->query_id= thd->query_id;
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    table->open_by_handler= 0;
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    mark_tmp_table_for_reuse(table);
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  }
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  /* Mark table as closed, ready for re-open if necessary. */
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  tables->table= NULL;
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  /* Safety, cleanup the pointer to satisfy MDL assertions. */
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  tables->mdl_request.ticket= NULL;
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}
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/*
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  Open a HANDLER table.
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  SYNOPSIS
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    mysql_ha_open()
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    thd                         Thread identifier.
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    tables                      A list of tables with the first entry to open.
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    reopen                      Re-open a previously opened handler table.
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  DESCRIPTION
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    Though this function takes a list of tables, only the first list entry
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    will be opened.
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    'reopen' is set when a handler table is to be re-opened. In this case,
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    'tables' is the pointer to the hashed TABLE_LIST object which has been
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    saved on the original open.
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    'reopen' is also used to suppress the sending of an 'ok' message.
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  RETURN
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    FALSE OK
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    TRUE  Error
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*/
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bool mysql_ha_open(THD *thd, TABLE_LIST *tables, bool reopen)
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{
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  TABLE_LIST    *hash_tables = NULL;
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  char          *db, *name, *alias;
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  uint          dblen, namelen, aliaslen, counter;
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  bool          error;
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  TABLE         *backup_open_tables;
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  MDL_ticket    *mdl_savepoint;
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  DBUG_ENTER("mysql_ha_open");
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  DBUG_PRINT("enter",("'%s'.'%s' as '%s'  reopen: %d",
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                      tables->db, tables->table_name, tables->alias,
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                      (int) reopen));
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  if (thd->locked_tables_mode)
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  {
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    my_error(ER_LOCK_OR_ACTIVE_TRANSACTION, MYF(0));
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    DBUG_RETURN(TRUE);
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  }
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  if (tables->schema_table)
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  {
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    my_error(ER_WRONG_USAGE, MYF(0), "HANDLER OPEN",
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             INFORMATION_SCHEMA_NAME.str);
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    DBUG_PRINT("exit",("ERROR"));
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    DBUG_RETURN(TRUE);
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  }
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  if (! my_hash_inited(&thd->handler_tables_hash))
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  {
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    /*
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      HASH entries are of type TABLE_LIST.
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    */
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    if (my_hash_init(&thd->handler_tables_hash, &my_charset_latin1,
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                     HANDLER_TABLES_HASH_SIZE, 0, 0,
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                     (my_hash_get_key) mysql_ha_hash_get_key,
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                     (my_hash_free_key) mysql_ha_hash_free, 0))
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    {
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      DBUG_PRINT("exit",("ERROR"));
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      DBUG_RETURN(TRUE);
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    }
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  }
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  else if (! reopen) /* Otherwise we have 'tables' already. */
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  {
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    if (my_hash_search(&thd->handler_tables_hash, (uchar*) tables->alias,
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                       strlen(tables->alias) + 1))
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    {
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      DBUG_PRINT("info",("duplicate '%s'", tables->alias));
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      DBUG_PRINT("exit",("ERROR"));
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      my_error(ER_NONUNIQ_TABLE, MYF(0), tables->alias);
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      DBUG_RETURN(TRUE);
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    }
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  }
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  if (! reopen)
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  {
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    /* copy the TABLE_LIST struct */
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    dblen= strlen(tables->db) + 1;
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    namelen= strlen(tables->table_name) + 1;
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    aliaslen= strlen(tables->alias) + 1;
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    if (!(my_multi_malloc(MYF(MY_WME),
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                          &hash_tables, (uint) sizeof(*hash_tables),
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                          &db, (uint) dblen,
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                          &name, (uint) namelen,
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                          &alias, (uint) aliaslen,
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                          NullS)))
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    {
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      DBUG_PRINT("exit",("ERROR"));
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      DBUG_RETURN(TRUE);
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    }
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    /* structure copy */
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    *hash_tables= *tables;
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    hash_tables->db= db;
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    hash_tables->table_name= name;
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    hash_tables->alias= alias;
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    memcpy(hash_tables->db, tables->db, dblen);
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    memcpy(hash_tables->table_name, tables->table_name, namelen);
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    memcpy(hash_tables->alias, tables->alias, aliaslen);
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    hash_tables->mdl_request.init(MDL_key::TABLE, db, name, MDL_SHARED);
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    /* for now HANDLER can be used only for real TABLES */
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    hash_tables->required_type= FRMTYPE_TABLE;
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    /* add to hash */
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    if (my_hash_insert(&thd->handler_tables_hash, (uchar*) hash_tables))
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    {
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      my_free(hash_tables);
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      DBUG_PRINT("exit",("ERROR"));
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      DBUG_RETURN(TRUE);
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    }
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  }
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  else
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    hash_tables= tables;
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  /*
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    Save and reset the open_tables list so that open_tables() won't
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    be able to access (or know about) the previous list. And on return
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    from open_tables(), thd->open_tables will contain only the opened
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    table.
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    See open_table() back-off comments for more details.
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  */
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  backup_open_tables= thd->open_tables;
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  thd->set_open_tables(NULL);
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  mdl_savepoint= thd->mdl_context.mdl_savepoint();
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  /*
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    open_tables() will set 'hash_tables->table' if successful.
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    It must be NULL for a real open when calling open_tables().
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  */
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  DBUG_ASSERT(! hash_tables->table);
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  /*
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    We use open_tables() here, rather than, say,
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    open_ltable() or open_table() because we would like to be able
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    to open a temporary table.
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  */
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  error= open_tables(thd, &hash_tables, &counter, 0);
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  if (! error &&
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      ! (hash_tables->table->file->ha_table_flags() & HA_CAN_SQL_HANDLER))
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  {
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    my_error(ER_ILLEGAL_HA, MYF(0), tables->alias);
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    error= TRUE;
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  }
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  if (!error &&
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      hash_tables->mdl_request.ticket &&
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      thd->mdl_context.has_lock(mdl_savepoint,
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                                hash_tables->mdl_request.ticket))
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  {
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    /* The ticket returned is within a savepoint. Make a copy.  */
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    error= thd->mdl_context.clone_ticket(&hash_tables->mdl_request);
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    hash_tables->table->mdl_ticket= hash_tables->mdl_request.ticket;
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  }
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  if (error)
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  {
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    /*
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      No need to rollback statement transaction, it's not started.
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      If called with reopen flag, no need to rollback either,
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      it will be done at statement end.
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    */
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    DBUG_ASSERT(thd->transaction.stmt.is_empty());
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    close_thread_tables(thd);
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    thd->mdl_context.rollback_to_savepoint(mdl_savepoint);
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    thd->set_open_tables(backup_open_tables);
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    if (!reopen)
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      my_hash_delete(&thd->handler_tables_hash, (uchar*) hash_tables);
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    else
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    {
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      hash_tables->table= NULL;
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      /* Safety, cleanup the pointer to satisfy MDL assertions. */
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      hash_tables->mdl_request.ticket= NULL;
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    }
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    DBUG_PRINT("exit",("ERROR"));
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    DBUG_RETURN(TRUE);
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  }
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  thd->set_open_tables(backup_open_tables);
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  if (hash_tables->mdl_request.ticket)
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  {
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    thd->mdl_context.
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      move_ticket_after_trans_sentinel(hash_tables->mdl_request.ticket);
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    thd->mdl_context.set_needs_thr_lock_abort(TRUE);
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  }
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  /*
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    Assert that the above check prevents opening of views and merge tables.
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    For temporary tables, TABLE::next can be set even if only one table
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    was opened for HANDLER as it is used to link them together
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    (see thd->temporary_tables).
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  */
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  DBUG_ASSERT(hash_tables->table->next == NULL ||
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              hash_tables->table->s->tmp_table);
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  /*
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    If it's a temp table, don't reset table->query_id as the table is
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    being used by this handler. For non-temp tables we use this flag
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    in asserts.
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  */
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  hash_tables->table->open_by_handler= 1;
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  if (! reopen)
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    my_ok(thd);
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  DBUG_PRINT("exit",("OK"));
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  DBUG_RETURN(FALSE);
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}
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/*
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  Close a HANDLER table by alias or table name
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  SYNOPSIS
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    mysql_ha_close()
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    thd                         Thread identifier.
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    tables                      A list of tables with the first entry to close.
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						|
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						|
  DESCRIPTION
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    Closes the table that is associated (on the handler tables hash) with the
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    name (table->alias) of the specified table.
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  RETURN
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    FALSE ok
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    TRUE  error
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*/
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bool mysql_ha_close(THD *thd, TABLE_LIST *tables)
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{
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  TABLE_LIST    *hash_tables;
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  DBUG_ENTER("mysql_ha_close");
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  DBUG_PRINT("enter",("'%s'.'%s' as '%s'",
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                      tables->db, tables->table_name, tables->alias));
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  if (thd->locked_tables_mode)
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  {
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    my_error(ER_LOCK_OR_ACTIVE_TRANSACTION, MYF(0));
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    DBUG_RETURN(TRUE);
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  }
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  if ((hash_tables= (TABLE_LIST*) my_hash_search(&thd->handler_tables_hash,
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                                                 (uchar*) tables->alias,
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                                                 strlen(tables->alias) + 1)))
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  {
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    mysql_ha_close_table(thd, hash_tables);
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    my_hash_delete(&thd->handler_tables_hash, (uchar*) hash_tables);
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  }
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  else
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  {
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    my_error(ER_UNKNOWN_TABLE, MYF(0), tables->alias, "HANDLER");
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    DBUG_PRINT("exit",("ERROR"));
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    DBUG_RETURN(TRUE);
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  }
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  /*
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    Mark MDL_context as no longer breaking protocol if we have
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    closed last HANDLER.
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  */
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  if (! thd->handler_tables_hash.records)
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    thd->mdl_context.set_needs_thr_lock_abort(FALSE);
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  my_ok(thd);
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  DBUG_PRINT("exit", ("OK"));
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  DBUG_RETURN(FALSE);
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}
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/**
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  A helper class to process an error from mysql_lock_tables().
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  HANDLER READ statement's attempt to lock the subject table
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  may get aborted if there is a pending DDL. In that case
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  we close the table, reopen it, and try to read again.
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  This is implicit and obscure, since HANDLER position
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  is lost in the process, but it's the legacy server
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  behaviour we should preserve.
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*/
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class Sql_handler_lock_error_handler: public Internal_error_handler
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{
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						|
public:
 | 
						|
  virtual
 | 
						|
  bool handle_condition(THD *thd,
 | 
						|
                        uint sql_errno,
 | 
						|
                        const char *sqlstate,
 | 
						|
                        MYSQL_ERROR::enum_warning_level level,
 | 
						|
                        const char* msg,
 | 
						|
                        MYSQL_ERROR **cond_hdl);
 | 
						|
 | 
						|
  bool need_reopen() const { return m_need_reopen; };
 | 
						|
  void init() { m_need_reopen= FALSE; };
 | 
						|
private:
 | 
						|
  bool m_need_reopen;
 | 
						|
};
 | 
						|
 | 
						|
 | 
						|
/**
 | 
						|
  Handle an error from mysql_lock_tables().
 | 
						|
  Ignore ER_LOCK_ABORTED errors.
 | 
						|
*/
 | 
						|
 | 
						|
bool
 | 
						|
Sql_handler_lock_error_handler::
 | 
						|
handle_condition(THD *thd,
 | 
						|
                 uint sql_errno,
 | 
						|
                 const char *sqlstate,
 | 
						|
                 MYSQL_ERROR::enum_warning_level level,
 | 
						|
                 const char* msg,
 | 
						|
                 MYSQL_ERROR **cond_hdl)
 | 
						|
{
 | 
						|
  *cond_hdl= NULL;
 | 
						|
  if (sql_errno == ER_LOCK_ABORTED)
 | 
						|
    m_need_reopen= TRUE;
 | 
						|
 | 
						|
  return m_need_reopen;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/*
 | 
						|
  Read from a HANDLER table.
 | 
						|
 | 
						|
  SYNOPSIS
 | 
						|
    mysql_ha_read()
 | 
						|
    thd                         Thread identifier.
 | 
						|
    tables                      A list of tables with the first entry to read.
 | 
						|
    mode
 | 
						|
    keyname
 | 
						|
    key_expr
 | 
						|
    ha_rkey_mode
 | 
						|
    cond
 | 
						|
    select_limit_cnt
 | 
						|
    offset_limit_cnt
 | 
						|
 | 
						|
  RETURN
 | 
						|
    FALSE ok
 | 
						|
    TRUE  error
 | 
						|
*/
 | 
						|
 
 | 
						|
bool mysql_ha_read(THD *thd, TABLE_LIST *tables,
 | 
						|
                   enum enum_ha_read_modes mode, char *keyname,
 | 
						|
                   List<Item> *key_expr,
 | 
						|
                   enum ha_rkey_function ha_rkey_mode, Item *cond,
 | 
						|
                   ha_rows select_limit_cnt, ha_rows offset_limit_cnt)
 | 
						|
{
 | 
						|
  TABLE_LIST    *hash_tables;
 | 
						|
  TABLE         *table, *backup_open_tables;
 | 
						|
  MYSQL_LOCK    *lock;
 | 
						|
  List<Item>	list;
 | 
						|
  Protocol	*protocol= thd->protocol;
 | 
						|
  char		buff[MAX_FIELD_WIDTH];
 | 
						|
  String	buffer(buff, sizeof(buff), system_charset_info);
 | 
						|
  int           error, keyno= -1;
 | 
						|
  uint          num_rows;
 | 
						|
  uchar		*UNINIT_VAR(key);
 | 
						|
  uint		UNINIT_VAR(key_len);
 | 
						|
  Sql_handler_lock_error_handler sql_handler_lock_error;
 | 
						|
  DBUG_ENTER("mysql_ha_read");
 | 
						|
  DBUG_PRINT("enter",("'%s'.'%s' as '%s'",
 | 
						|
                      tables->db, tables->table_name, tables->alias));
 | 
						|
 | 
						|
  if (thd->locked_tables_mode)
 | 
						|
  {
 | 
						|
    my_error(ER_LOCK_OR_ACTIVE_TRANSACTION, MYF(0));
 | 
						|
    DBUG_RETURN(TRUE);
 | 
						|
  }
 | 
						|
 | 
						|
  thd->lex->select_lex.context.resolve_in_table_list_only(tables);
 | 
						|
  list.push_front(new Item_field(&thd->lex->select_lex.context,
 | 
						|
                                 NULL, NULL, "*"));
 | 
						|
  List_iterator<Item> it(list);
 | 
						|
  it++;
 | 
						|
 | 
						|
retry:
 | 
						|
  if ((hash_tables= (TABLE_LIST*) my_hash_search(&thd->handler_tables_hash,
 | 
						|
                                                 (uchar*) tables->alias,
 | 
						|
                                                 strlen(tables->alias) + 1)))
 | 
						|
  {
 | 
						|
    table= hash_tables->table;
 | 
						|
    DBUG_PRINT("info-in-hash",("'%s'.'%s' as '%s' table: 0x%lx",
 | 
						|
                               hash_tables->db, hash_tables->table_name,
 | 
						|
                               hash_tables->alias, (long) table));
 | 
						|
    if (!table)
 | 
						|
    {
 | 
						|
      /*
 | 
						|
        The handler table has been closed. Re-open it.
 | 
						|
      */
 | 
						|
      if (mysql_ha_open(thd, hash_tables, 1))
 | 
						|
      {
 | 
						|
        DBUG_PRINT("exit",("reopen failed"));
 | 
						|
        goto err0;
 | 
						|
      }
 | 
						|
 | 
						|
      table= hash_tables->table;
 | 
						|
      DBUG_PRINT("info",("re-opened '%s'.'%s' as '%s' tab %p",
 | 
						|
                         hash_tables->db, hash_tables->table_name,
 | 
						|
                         hash_tables->alias, table));
 | 
						|
    }
 | 
						|
  }
 | 
						|
  else
 | 
						|
    table= NULL;
 | 
						|
 | 
						|
  if (!table)
 | 
						|
  {
 | 
						|
    my_error(ER_UNKNOWN_TABLE, MYF(0), tables->alias, "HANDLER");
 | 
						|
    goto err0;
 | 
						|
  }
 | 
						|
 | 
						|
  /* save open_tables state */
 | 
						|
  backup_open_tables= thd->open_tables;
 | 
						|
  /* Always a one-element list, see mysql_ha_open(). */
 | 
						|
  DBUG_ASSERT(hash_tables->table->next == NULL ||
 | 
						|
              hash_tables->table->s->tmp_table);
 | 
						|
  /*
 | 
						|
    mysql_lock_tables() needs thd->open_tables to be set correctly to
 | 
						|
    be able to handle aborts properly.
 | 
						|
  */
 | 
						|
  thd->set_open_tables(hash_tables->table);
 | 
						|
 | 
						|
 | 
						|
  sql_handler_lock_error.init();
 | 
						|
  thd->push_internal_handler(&sql_handler_lock_error);
 | 
						|
 | 
						|
  lock= mysql_lock_tables(thd, &thd->open_tables, 1, 0);
 | 
						|
 | 
						|
  thd->pop_internal_handler();
 | 
						|
  /*
 | 
						|
    In 5.1 and earlier, mysql_lock_tables() could replace the TABLE
 | 
						|
    object with another one (reopen it). This is no longer the case
 | 
						|
    with new MDL.
 | 
						|
  */
 | 
						|
  DBUG_ASSERT(hash_tables->table == thd->open_tables);
 | 
						|
  /* Restore previous context. */
 | 
						|
  thd->set_open_tables(backup_open_tables);
 | 
						|
 | 
						|
  if (sql_handler_lock_error.need_reopen())
 | 
						|
  {
 | 
						|
    DBUG_ASSERT(!lock && !thd->is_error());
 | 
						|
    /*
 | 
						|
      Always close statement transaction explicitly,
 | 
						|
      so that the engine doesn't have to count locks.
 | 
						|
    */
 | 
						|
    trans_rollback_stmt(thd);
 | 
						|
    mysql_ha_close_table(thd, hash_tables);
 | 
						|
    goto retry;
 | 
						|
  }
 | 
						|
 | 
						|
  if (!lock)
 | 
						|
    goto err0; // mysql_lock_tables() printed error message already
 | 
						|
 | 
						|
  // Always read all columns
 | 
						|
  hash_tables->table->read_set= &hash_tables->table->s->all_set;
 | 
						|
  tables->table= hash_tables->table;
 | 
						|
 | 
						|
  if (cond)
 | 
						|
  {
 | 
						|
    if (table->query_id != thd->query_id)
 | 
						|
      cond->cleanup();                          // File was reopened
 | 
						|
    if ((!cond->fixed &&
 | 
						|
	 cond->fix_fields(thd, &cond)) || cond->check_cols(1))
 | 
						|
      goto err;
 | 
						|
  }
 | 
						|
 | 
						|
  if (keyname)
 | 
						|
  {
 | 
						|
    if ((keyno=find_type(keyname, &table->s->keynames, 1+2)-1)<0)
 | 
						|
    {
 | 
						|
      my_error(ER_KEY_DOES_NOT_EXITS, MYF(0), keyname, tables->alias);
 | 
						|
      goto err;
 | 
						|
    }
 | 
						|
    /* Check if the same index involved. */
 | 
						|
    if ((uint) keyno != table->file->get_index())
 | 
						|
    {
 | 
						|
      if (mode == RNEXT)
 | 
						|
        mode= RFIRST;
 | 
						|
      else if (mode == RPREV)
 | 
						|
        mode= RLAST;
 | 
						|
    }
 | 
						|
  }
 | 
						|
 | 
						|
  if (insert_fields(thd, &thd->lex->select_lex.context,
 | 
						|
                    tables->db, tables->alias, &it, 0))
 | 
						|
    goto err;
 | 
						|
 | 
						|
  protocol->send_result_set_metadata(&list, Protocol::SEND_NUM_ROWS | Protocol::SEND_EOF);
 | 
						|
 | 
						|
  /*
 | 
						|
    In ::external_lock InnoDB resets the fields which tell it that
 | 
						|
    the handle is used in the HANDLER interface. Tell it again that
 | 
						|
    we are using it for HANDLER.
 | 
						|
  */
 | 
						|
 | 
						|
  table->file->init_table_handle_for_HANDLER();
 | 
						|
 | 
						|
  for (num_rows=0; num_rows < select_limit_cnt; )
 | 
						|
  {
 | 
						|
    switch (mode) {
 | 
						|
    case RNEXT:
 | 
						|
      if (table->file->inited != handler::NONE)
 | 
						|
      {
 | 
						|
        if (keyname)
 | 
						|
        {
 | 
						|
          /* Check if we read from the same index. */
 | 
						|
          DBUG_ASSERT((uint) keyno == table->file->get_index());
 | 
						|
          error= table->file->index_next(table->record[0]);
 | 
						|
        }
 | 
						|
        else
 | 
						|
        {
 | 
						|
          error= table->file->rnd_next(table->record[0]);
 | 
						|
        }
 | 
						|
        break;
 | 
						|
      }
 | 
						|
      /* else fall through */
 | 
						|
    case RFIRST:
 | 
						|
      if (keyname)
 | 
						|
      {
 | 
						|
        table->file->ha_index_or_rnd_end();
 | 
						|
        table->file->ha_index_init(keyno, 1);
 | 
						|
        error= table->file->index_first(table->record[0]);
 | 
						|
      }
 | 
						|
      else
 | 
						|
      {
 | 
						|
        table->file->ha_index_or_rnd_end();
 | 
						|
	if (!(error= table->file->ha_rnd_init(1)))
 | 
						|
          error= table->file->rnd_next(table->record[0]);
 | 
						|
      }
 | 
						|
      mode=RNEXT;
 | 
						|
      break;
 | 
						|
    case RPREV:
 | 
						|
      DBUG_ASSERT(keyname != 0);
 | 
						|
      /* Check if we read from the same index. */
 | 
						|
      DBUG_ASSERT((uint) keyno == table->file->get_index());
 | 
						|
      if (table->file->inited != handler::NONE)
 | 
						|
      {
 | 
						|
        error=table->file->index_prev(table->record[0]);
 | 
						|
        break;
 | 
						|
      }
 | 
						|
      /* else fall through */
 | 
						|
    case RLAST:
 | 
						|
      DBUG_ASSERT(keyname != 0);
 | 
						|
      table->file->ha_index_or_rnd_end();
 | 
						|
      table->file->ha_index_init(keyno, 1);
 | 
						|
      error= table->file->index_last(table->record[0]);
 | 
						|
      mode=RPREV;
 | 
						|
      break;
 | 
						|
    case RNEXT_SAME:
 | 
						|
      /* Continue scan on "(keypart1,keypart2,...)=(c1, c2, ...)  */
 | 
						|
      DBUG_ASSERT(keyname != 0);
 | 
						|
      error= table->file->index_next_same(table->record[0], key, key_len);
 | 
						|
      break;
 | 
						|
    case RKEY:
 | 
						|
    {
 | 
						|
      DBUG_ASSERT(keyname != 0);
 | 
						|
      KEY *keyinfo=table->key_info+keyno;
 | 
						|
      KEY_PART_INFO *key_part=keyinfo->key_part;
 | 
						|
      if (key_expr->elements > keyinfo->key_parts)
 | 
						|
      {
 | 
						|
	my_error(ER_TOO_MANY_KEY_PARTS, MYF(0), keyinfo->key_parts);
 | 
						|
	goto err;
 | 
						|
      }
 | 
						|
      List_iterator<Item> it_ke(*key_expr);
 | 
						|
      Item *item;
 | 
						|
      key_part_map keypart_map;
 | 
						|
      for (keypart_map= key_len=0 ; (item=it_ke++) ; key_part++)
 | 
						|
      {
 | 
						|
        my_bitmap_map *old_map;
 | 
						|
	// 'item' can be changed by fix_fields() call
 | 
						|
        if ((!item->fixed &&
 | 
						|
             item->fix_fields(thd, it_ke.ref())) ||
 | 
						|
	    (item= *it_ke.ref())->check_cols(1))
 | 
						|
	  goto err;
 | 
						|
	if (item->used_tables() & ~RAND_TABLE_BIT)
 | 
						|
        {
 | 
						|
          my_error(ER_WRONG_ARGUMENTS,MYF(0),"HANDLER ... READ");
 | 
						|
	  goto err;
 | 
						|
        }
 | 
						|
        old_map= dbug_tmp_use_all_columns(table, table->write_set);
 | 
						|
	(void) item->save_in_field(key_part->field, 1);
 | 
						|
        dbug_tmp_restore_column_map(table->write_set, old_map);
 | 
						|
	key_len+=key_part->store_length;
 | 
						|
        keypart_map= (keypart_map << 1) | 1;
 | 
						|
      }
 | 
						|
 | 
						|
      if (!(key= (uchar*) thd->calloc(ALIGN_SIZE(key_len))))
 | 
						|
	goto err;
 | 
						|
      table->file->ha_index_or_rnd_end();
 | 
						|
      table->file->ha_index_init(keyno, 1);
 | 
						|
      key_copy(key, table->record[0], table->key_info + keyno, key_len);
 | 
						|
      error= table->file->index_read_map(table->record[0],
 | 
						|
                                         key, keypart_map, ha_rkey_mode);
 | 
						|
      mode=rkey_to_rnext[(int)ha_rkey_mode];
 | 
						|
      break;
 | 
						|
    }
 | 
						|
    default:
 | 
						|
      my_message(ER_ILLEGAL_HA, ER(ER_ILLEGAL_HA), MYF(0));
 | 
						|
      goto err;
 | 
						|
    }
 | 
						|
 | 
						|
    if (error)
 | 
						|
    {
 | 
						|
      if (error == HA_ERR_RECORD_DELETED)
 | 
						|
        continue;
 | 
						|
      if (error != HA_ERR_KEY_NOT_FOUND && error != HA_ERR_END_OF_FILE)
 | 
						|
      {
 | 
						|
        sql_print_error("mysql_ha_read: Got error %d when reading table '%s'",
 | 
						|
                        error, tables->table_name);
 | 
						|
        table->file->print_error(error,MYF(0));
 | 
						|
        goto err;
 | 
						|
      }
 | 
						|
      goto ok;
 | 
						|
    }
 | 
						|
    if (cond && !cond->val_int())
 | 
						|
    {
 | 
						|
      if (thd->is_error())
 | 
						|
        goto err;
 | 
						|
      continue;
 | 
						|
    }
 | 
						|
    if (num_rows >= offset_limit_cnt)
 | 
						|
    {
 | 
						|
      protocol->prepare_for_resend();
 | 
						|
 | 
						|
      if (protocol->send_result_set_row(&list))
 | 
						|
        goto err;
 | 
						|
 | 
						|
      protocol->write();
 | 
						|
    }
 | 
						|
    num_rows++;
 | 
						|
  }
 | 
						|
ok:
 | 
						|
  /*
 | 
						|
    Always close statement transaction explicitly,
 | 
						|
    so that the engine doesn't have to count locks.
 | 
						|
  */
 | 
						|
  trans_commit_stmt(thd);
 | 
						|
  mysql_unlock_tables(thd,lock);
 | 
						|
  my_eof(thd);
 | 
						|
  DBUG_PRINT("exit",("OK"));
 | 
						|
  DBUG_RETURN(FALSE);
 | 
						|
 | 
						|
err:
 | 
						|
  trans_rollback_stmt(thd);
 | 
						|
  mysql_unlock_tables(thd,lock);
 | 
						|
err0:
 | 
						|
  DBUG_PRINT("exit",("ERROR"));
 | 
						|
  DBUG_RETURN(TRUE);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/**
 | 
						|
  Scan the handler tables hash for matching tables.
 | 
						|
 | 
						|
  @param thd Thread identifier.
 | 
						|
  @param tables The list of tables to remove.
 | 
						|
 | 
						|
  @return Pointer to head of linked list (TABLE_LIST::next_local) of matching
 | 
						|
          TABLE_LIST elements from handler_tables_hash. Otherwise, NULL if no
 | 
						|
          table was matched.
 | 
						|
*/
 | 
						|
 | 
						|
static TABLE_LIST *mysql_ha_find(THD *thd, TABLE_LIST *tables)
 | 
						|
{
 | 
						|
  TABLE_LIST *hash_tables, *head= NULL, *first= tables;
 | 
						|
  DBUG_ENTER("mysql_ha_find");
 | 
						|
 | 
						|
  /* search for all handlers with matching table names */
 | 
						|
  for (uint i= 0; i < thd->handler_tables_hash.records; i++)
 | 
						|
  {
 | 
						|
    hash_tables= (TABLE_LIST*) my_hash_element(&thd->handler_tables_hash, i);
 | 
						|
    for (tables= first; tables; tables= tables->next_local)
 | 
						|
    {
 | 
						|
      if ((! *tables->db ||
 | 
						|
          ! my_strcasecmp(&my_charset_latin1, hash_tables->db, tables->db)) &&
 | 
						|
          ! my_strcasecmp(&my_charset_latin1, hash_tables->table_name,
 | 
						|
                          tables->table_name))
 | 
						|
        break;
 | 
						|
    }
 | 
						|
    if (tables)
 | 
						|
    {
 | 
						|
      hash_tables->next_local= head;
 | 
						|
      head= hash_tables;
 | 
						|
    }
 | 
						|
  }
 | 
						|
 | 
						|
  DBUG_RETURN(head);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/**
 | 
						|
  Remove matching tables from the HANDLER's hash table.
 | 
						|
 | 
						|
  @param thd Thread identifier.
 | 
						|
  @param tables The list of tables to remove.
 | 
						|
 | 
						|
  @note Broadcasts refresh if it closed a table with old version.
 | 
						|
*/
 | 
						|
 | 
						|
void mysql_ha_rm_tables(THD *thd, TABLE_LIST *tables)
 | 
						|
{
 | 
						|
  TABLE_LIST *hash_tables, *next;
 | 
						|
  DBUG_ENTER("mysql_ha_rm_tables");
 | 
						|
 | 
						|
  DBUG_ASSERT(tables);
 | 
						|
 | 
						|
  hash_tables= mysql_ha_find(thd, tables);
 | 
						|
 | 
						|
  while (hash_tables)
 | 
						|
  {
 | 
						|
    next= hash_tables->next_local;
 | 
						|
    if (hash_tables->table)
 | 
						|
      mysql_ha_close_table(thd, hash_tables);
 | 
						|
    my_hash_delete(&thd->handler_tables_hash, (uchar*) hash_tables);
 | 
						|
    hash_tables= next;
 | 
						|
  }
 | 
						|
 | 
						|
  /*
 | 
						|
    Mark MDL_context as no longer breaking protocol if we have
 | 
						|
    closed last HANDLER.
 | 
						|
  */
 | 
						|
  if (! thd->handler_tables_hash.records)
 | 
						|
    thd->mdl_context.set_needs_thr_lock_abort(FALSE);
 | 
						|
 | 
						|
  DBUG_VOID_RETURN;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/**
 | 
						|
  Close cursors of matching tables from the HANDLER's hash table.
 | 
						|
 | 
						|
  @param thd Thread identifier.
 | 
						|
  @param tables The list of tables to flush.
 | 
						|
*/
 | 
						|
 | 
						|
void mysql_ha_flush_tables(THD *thd, TABLE_LIST *all_tables)
 | 
						|
{
 | 
						|
  DBUG_ENTER("mysql_ha_flush_tables");
 | 
						|
 | 
						|
  for (TABLE_LIST *table_list= all_tables; table_list;
 | 
						|
       table_list= table_list->next_global)
 | 
						|
  {
 | 
						|
    TABLE_LIST *hash_tables= mysql_ha_find(thd, table_list);
 | 
						|
    /* Close all aliases of the same table. */
 | 
						|
    while (hash_tables)
 | 
						|
    {
 | 
						|
      TABLE_LIST *next_local= hash_tables->next_local;
 | 
						|
      if (hash_tables->table)
 | 
						|
        mysql_ha_close_table(thd, hash_tables);
 | 
						|
      hash_tables= next_local;
 | 
						|
    }
 | 
						|
  }
 | 
						|
 | 
						|
  DBUG_VOID_RETURN;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/**
 | 
						|
  Flush (close and mark for re-open) all tables that should be should
 | 
						|
  be reopen.
 | 
						|
 | 
						|
  @param thd Thread identifier.
 | 
						|
 | 
						|
  @note Broadcasts refresh if it closed a table with old version.
 | 
						|
*/
 | 
						|
 | 
						|
void mysql_ha_flush(THD *thd)
 | 
						|
{
 | 
						|
  TABLE_LIST *hash_tables;
 | 
						|
  DBUG_ENTER("mysql_ha_flush");
 | 
						|
 | 
						|
  mysql_mutex_assert_not_owner(&LOCK_open);
 | 
						|
 | 
						|
  /*
 | 
						|
    Don't try to flush open HANDLERs when we're working with
 | 
						|
    system tables. The main MDL context is backed up and we can't
 | 
						|
    properly release HANDLER locks stored there.
 | 
						|
  */
 | 
						|
  if (thd->state_flags & Open_tables_state::BACKUPS_AVAIL)
 | 
						|
    DBUG_VOID_RETURN;
 | 
						|
 | 
						|
  for (uint i= 0; i < thd->handler_tables_hash.records; i++)
 | 
						|
  {
 | 
						|
    hash_tables= (TABLE_LIST*) my_hash_element(&thd->handler_tables_hash, i);
 | 
						|
    /*
 | 
						|
      TABLE::mdl_ticket is 0 for temporary tables so we need extra check.
 | 
						|
    */
 | 
						|
    if (hash_tables->table &&
 | 
						|
        ((hash_tables->table->mdl_ticket &&
 | 
						|
         hash_tables->table->mdl_ticket->has_pending_conflicting_lock()) ||
 | 
						|
         (!hash_tables->table->s->tmp_table &&
 | 
						|
          hash_tables->table->s->has_old_version())))
 | 
						|
      mysql_ha_close_table(thd, hash_tables);
 | 
						|
  }
 | 
						|
 | 
						|
  DBUG_VOID_RETURN;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/**
 | 
						|
  Close all HANDLER's tables.
 | 
						|
 | 
						|
  @param thd Thread identifier.
 | 
						|
 | 
						|
  @note Broadcasts refresh if it closed a table with old version.
 | 
						|
*/
 | 
						|
 | 
						|
void mysql_ha_cleanup(THD *thd)
 | 
						|
{
 | 
						|
  TABLE_LIST *hash_tables;
 | 
						|
  DBUG_ENTER("mysql_ha_cleanup");
 | 
						|
 | 
						|
  for (uint i= 0; i < thd->handler_tables_hash.records; i++)
 | 
						|
  {
 | 
						|
    hash_tables= (TABLE_LIST*) my_hash_element(&thd->handler_tables_hash, i);
 | 
						|
    if (hash_tables->table)
 | 
						|
      mysql_ha_close_table(thd, hash_tables);
 | 
						|
  }
 | 
						|
 | 
						|
  my_hash_free(&thd->handler_tables_hash);
 | 
						|
 | 
						|
  DBUG_VOID_RETURN;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/**
 | 
						|
  Move tickets for metadata locks corresponding to open HANDLERs
 | 
						|
  after transaction sentinel in order to protect them from being
 | 
						|
  released at the end of transaction.
 | 
						|
 | 
						|
  @param thd Thread identifier.
 | 
						|
*/
 | 
						|
 | 
						|
void mysql_ha_move_tickets_after_trans_sentinel(THD *thd)
 | 
						|
{
 | 
						|
  TABLE_LIST *hash_tables;
 | 
						|
  DBUG_ENTER("mysql_ha_move_tickets_after_trans_sentinel");
 | 
						|
 | 
						|
  for (uint i= 0; i < thd->handler_tables_hash.records; i++)
 | 
						|
  {
 | 
						|
    hash_tables= (TABLE_LIST*) my_hash_element(&thd->handler_tables_hash, i);
 | 
						|
    if (hash_tables->table && hash_tables->table->mdl_ticket)
 | 
						|
      thd->mdl_context.
 | 
						|
             move_ticket_after_trans_sentinel(hash_tables->table->mdl_ticket);
 | 
						|
  }
 | 
						|
  DBUG_VOID_RETURN;
 | 
						|
}
 | 
						|
 |