sql_base.cc

/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */


/* Basic functions needed by many modules */

#include "mysql_priv.h"
#include "sql_select.h"
#include "sp_head.h"
#include "sp.h"
#include "sql_trigger.h"
#include <m_ctype.h>
#include <my_dir.h>
#include <hash.h>
#ifdef	__WIN__
#include <io.h>
#endif

TABLE *unused_tables;				/* Used by mysql_test */
HASH open_cache;				/* Used by mysql_test */

static int open_unireg_entry(THD *thd, TABLE *entry, const char *db,
			     const char *name, const char *alias,
			     TABLE_LIST *table_list, MEM_ROOT *mem_root);
static void free_cache_entry(TABLE *entry);
static void mysql_rm_tmp_tables(void);
static my_bool open_new_frm(const char *path, const char *alias,
                            const char *db, const char *table_name,
			    uint db_stat, uint prgflag,
			    uint ha_open_flags, TABLE *outparam,
			    TABLE_LIST *table_desc, MEM_ROOT *mem_root);

extern "C" byte *table_cache_key(const byte *record,uint *length,
				 my_bool not_used __attribute__((unused)))
{
  TABLE *entry=(TABLE*) record;
  *length= entry->s->key_length;
  return (byte*) entry->s->table_cache_key;
}

bool table_cache_init(void)
{
  mysql_rm_tmp_tables();
  return hash_init(&open_cache, &my_charset_bin, table_cache_size+16,
		   0, 0,table_cache_key,
		   (hash_free_key) free_cache_entry, 0) != 0;
}

void table_cache_free(void)
{
  DBUG_ENTER("table_cache_free");
  close_cached_tables((THD*) 0,0,(TABLE_LIST*) 0);
  if (!open_cache.records)			// Safety first
    hash_free(&open_cache);
  DBUG_VOID_RETURN;
}

uint cached_tables(void)
{
  return open_cache.records;
}

#ifdef EXTRA_DEBUG
static void check_unused(void)
{
  uint count=0,idx=0;
  TABLE *cur_link,*start_link;

  if ((start_link=cur_link=unused_tables))
  {
    do
    {
      if (cur_link != cur_link->next->prev || cur_link != cur_link->prev->next)
      {
	DBUG_PRINT("error",("Unused_links aren't linked properly")); /* purecov: inspected */
	return; /* purecov: inspected */
      }
    } while (count++ < open_cache.records &&
	     (cur_link=cur_link->next) != start_link);
    if (cur_link != start_link)
    {
      DBUG_PRINT("error",("Unused_links aren't connected")); /* purecov: inspected */
    }
  }
  for (idx=0 ; idx < open_cache.records ; idx++)
  {
    TABLE *entry=(TABLE*) hash_element(&open_cache,idx);
    if (!entry->in_use)
      count--;
  }
  if (count != 0)
  {
    DBUG_PRINT("error",("Unused_links doesn't match open_cache: diff: %d", /* purecov: inspected */
			count)); /* purecov: inspected */
  }
}
#else
#define check_unused()
#endif

/*
  Create a list for all open tables matching SQL expression

  SYNOPSIS
    list_open_tables()
    thd			Thread THD
    wild		SQL like expression

  NOTES
    One gets only a list of tables for which one has any kind of privilege.
    db and table names are allocated in result struct, so one doesn't need
    a lock on LOCK_open when traversing the return list.

  RETURN VALUES
    NULL	Error (Probably OOM)
    #		Pointer to list of names of open tables.
*/

OPEN_TABLE_LIST *list_open_tables(THD *thd, const char *wild)
{
  int result = 0;
  OPEN_TABLE_LIST **start_list, *open_list;
  TABLE_LIST table_list;
  char name[NAME_LEN*2];
  DBUG_ENTER("list_open_tables");

  VOID(pthread_mutex_lock(&LOCK_open));
  bzero((char*) &table_list,sizeof(table_list));
  start_list= &open_list;
  open_list=0;

  for (uint idx=0 ; result == 0 && idx < open_cache.records; idx++)
  {
    OPEN_TABLE_LIST *table;
    TABLE *entry=(TABLE*) hash_element(&open_cache,idx);
    TABLE_SHARE *share= entry->s;

    DBUG_ASSERT(share->table_name != 0);
    if ((!share->table_name))			// To be removed
      continue;					// Shouldn't happen
    if (wild)
    {
      strxmov(name,share->table_cache_key,".",share->table_name,NullS);
      if (wild_compare(name,wild,0))
	continue;
    }

    /* Check if user has SELECT privilege for any column in the table */
    table_list.db=        (char*) share->db;
    table_list.table_name= (char*) share->table_name;
    table_list.grant.privilege=0;

    if (check_table_access(thd,SELECT_ACL | EXTRA_ACL,&table_list,1))
      continue;
    /* need to check if we haven't already listed it */
    for (table= open_list  ; table ; table=table->next)
    {
      if (!strcmp(table->table,share->table_name) &&
	  !strcmp(table->db,entry->s->db))
      {
	if (entry->in_use)
	  table->in_use++;
	if (entry->locked_by_name)
	  table->locked++;
	break;
      }
    }
    if (table)
      continue;
    if (!(*start_list = (OPEN_TABLE_LIST *)
	  sql_alloc(sizeof(**start_list)+share->key_length)))
    {
      open_list=0;				// Out of memory
      break;
    }
    strmov((*start_list)->table=
	   strmov(((*start_list)->db= (char*) ((*start_list)+1)),
		  entry->s->db)+1,
	   entry->s->table_name);
    (*start_list)->in_use= entry->in_use ? 1 : 0;
    (*start_list)->locked= entry->locked_by_name ? 1 : 0;
    start_list= &(*start_list)->next;
    *start_list=0;
  }
  VOID(pthread_mutex_unlock(&LOCK_open));
  DBUG_RETURN(open_list);
}

/*****************************************************************************
 *	 Functions to free open table cache
 ****************************************************************************/


void intern_close_table(TABLE *table)
{						// Free all structures
  free_io_cache(table);
  delete table->triggers;
  if (table->file)
    VOID(closefrm(table));			// close file
}

/*
  Remove table from the open table cache

  SYNOPSIS
    free_cache_entry()
    table		Table to remove

  NOTE
    We need to have a lock on LOCK_open when calling this
*/

static void free_cache_entry(TABLE *table)
{
  DBUG_ENTER("free_cache_entry");
  safe_mutex_assert_owner(&LOCK_open);

  intern_close_table(table);
  if (!table->in_use)
  {
    table->next->prev=table->prev;		/* remove from used chain */
    table->prev->next=table->next;
    if (table == unused_tables)
    {
      unused_tables=unused_tables->next;
      if (table == unused_tables)
	unused_tables=0;
    }
    check_unused();				// consisty check
  }
  my_free((gptr) table,MYF(0));
  DBUG_VOID_RETURN;
}

/* Free resources allocated by filesort() and read_record() */

void free_io_cache(TABLE *table)
{
  DBUG_ENTER("free_io_cache");
  if (table->sort.io_cache)
  {
    close_cached_file(table->sort.io_cache);
    my_free((gptr) table->sort.io_cache,MYF(0));
    table->sort.io_cache=0;
  }
  DBUG_VOID_RETURN;
}

/*
  Close all tables which aren't in use by any thread

  THD can be NULL, but then if_wait_for_refresh must be FALSE
  and tables must be NULL.
*/

bool close_cached_tables(THD *thd, bool if_wait_for_refresh,
			 TABLE_LIST *tables)
{
  bool result=0;
  DBUG_ENTER("close_cached_tables");
  DBUG_ASSERT(thd || (!if_wait_for_refresh && !tables));

  VOID(pthread_mutex_lock(&LOCK_open));
  if (!tables)
  {
    while (unused_tables)
    {
#ifdef EXTRA_DEBUG
      if (hash_delete(&open_cache,(byte*) unused_tables))
	printf("Warning: Couldn't delete open table from hash\n");
#else
      VOID(hash_delete(&open_cache,(byte*) unused_tables));
#endif
    }
    refresh_version++;				// Force close of open tables
  }
  else
  {
    bool found=0;
    for (TABLE_LIST *table= tables; table; table= table->next_local)
    {
      if (remove_table_from_cache(thd, table->db, table->table_name,
                                  RTFC_OWNED_BY_THD_FLAG))
	found=1;
    }
    if (!found)
      if_wait_for_refresh=0;			// Nothing to wait for
  }
#ifndef EMBEDDED_LIBRARY
  if (!tables)
    kill_delayed_threads();
#endif
  if (if_wait_for_refresh)
  {
    /*
      If there is any table that has a lower refresh_version, wait until
      this is closed (or this thread is killed) before returning
    */
    thd->mysys_var->current_mutex= &LOCK_open;
    thd->mysys_var->current_cond= &COND_refresh;
    thd->proc_info="Flushing tables";

    close_old_data_files(thd,thd->open_tables,1,1);
    mysql_ha_flush(thd, tables, MYSQL_HA_REOPEN_ON_USAGE | MYSQL_HA_FLUSH_ALL);
    bool found=1;
    /* Wait until all threads has closed all the tables we had locked */
    DBUG_PRINT("info",
	       ("Waiting for others threads to close their open tables"));
    while (found && ! thd->killed)
    {
      found=0;
      for (uint idx=0 ; idx < open_cache.records ; idx++)
      {
	TABLE *table=(TABLE*) hash_element(&open_cache,idx);
	if ((table->s->version) < refresh_version && table->db_stat)
	{
	  found=1;
	  pthread_cond_wait(&COND_refresh,&LOCK_open);
	  break;
	}
      }
    }
    /*
      No other thread has the locked tables open; reopen them and get the
      old locks. This should always succeed (unless some external process
      has removed the tables)
    */
    thd->in_lock_tables=1;
    result=reopen_tables(thd,1,1);
    thd->in_lock_tables=0;
    /* Set version for table */
    for (TABLE *table=thd->open_tables; table ; table= table->next)
      table->s->version= refresh_version;
  }
  VOID(pthread_mutex_unlock(&LOCK_open));
  if (if_wait_for_refresh)
  {
    pthread_mutex_lock(&thd->mysys_var->mutex);
    thd->mysys_var->current_mutex= 0;
    thd->mysys_var->current_cond= 0;
    thd->proc_info=0;
    pthread_mutex_unlock(&thd->mysys_var->mutex);
  }
  DBUG_RETURN(result);
}


/*
  Mark all tables in the list which were used by current substatement
  as free for reuse.

  SYNOPSIS
    mark_used_tables_as_free_for_reuse()
      thd   - thread context
      table - head of the list of tables

  DESCRIPTION
    Marks all tables in the list which were used by current substatement
    (they are marked by its query_id) as free for reuse.
*/

static void mark_used_tables_as_free_for_reuse(THD *thd, TABLE *table)
{
  for (; table ; table= table->next)
    if (table->query_id == thd->query_id)
      table->query_id= 0;
}


/*
  Close all tables used by the current substatement, or all tables
  used by this thread if we are on the upper level.

  SYNOPSIS
    close_thread_tables()
    thd			Thread handler
    lock_in_use		Set to 1 (0 = default) if caller has a lock on
			LOCK_open
    skip_derived	Set to 1 (0 = default) if we should not free derived
			tables.

  IMPLEMENTATION
    Unlocks tables and frees derived tables.
    Put all normal tables used by thread in free list.

    When in prelocked mode it will only close/mark as free for reuse
    tables opened by this substatement, it will also check if we are
    closing tables after execution of complete query (i.e. we are on
    upper level) and will leave prelocked mode if needed.
*/

void close_thread_tables(THD *thd, bool lock_in_use, bool skip_derived, 
                         TABLE *stopper)
{
  bool found_old_table;
  prelocked_mode_type prelocked_mode= thd->prelocked_mode;
  DBUG_ENTER("close_thread_tables");

  /*
    We are assuming here that thd->derived_tables contains ONLY derived
    tables for this substatement. i.e. instead of approach which uses
    query_id matching for determining which of the derived tables belong
    to this substatement we rely on the ability of substatements to
    save/restore thd->derived_tables during their execution.

    TODO: Probably even better approach is to simply associate list of
          derived tables with (sub-)statement instead of thread and destroy
          them at the end of its execution.
  */
  if (thd->derived_tables && !skip_derived)
  {
    TABLE *table, *next;
    /*
      Close all derived tables generated in queries like
      SELECT * FROM (SELECT * FROM t1)
    */
    for (table= thd->derived_tables ; table ; table= next)
    {
      next= table->next;
      free_tmp_table(thd, table);
    }
    thd->derived_tables= 0;
  }

  if (prelocked_mode)
  {
    /*
      Mark all temporary tables used by this substatement as free for reuse.
    */
    mark_used_tables_as_free_for_reuse(thd, thd->temporary_tables);
  }

  if (thd->locked_tables || prelocked_mode)
  {
    /*
      Let us commit transaction for statement. Since in 5.0 we only have
      one statement transaction and don't allow several nested statement
      transactions this call will do nothing if we are inside of stored
      function or trigger (i.e. statement transaction is already active and
      does not belong to statement for which we do close_thread_tables()).
      TODO: This should be fixed in later releases.
    */
    ha_commit_stmt(thd);

    /* We are under simple LOCK TABLES so should not do anything else. */
    if (!prelocked_mode)
      DBUG_VOID_RETURN;

    if (!thd->lex->requires_prelocking())
    {
      /*
        If we are executing one of substatements we have to mark
        all tables which it used as free for reuse.
      */
      mark_used_tables_as_free_for_reuse(thd, thd->open_tables);
      DBUG_VOID_RETURN;
    }

    DBUG_ASSERT(prelocked_mode);
    /*
      We are in prelocked mode, so we have to leave it now with doing
      implicit UNLOCK TABLES if need.
    */
    thd->prelocked_mode= NON_PRELOCKED;

    if (prelocked_mode == PRELOCKED_UNDER_LOCK_TABLES)
      DBUG_VOID_RETURN;

    thd->lock= thd->locked_tables;
    thd->locked_tables= 0;
    /* Fallthrough */
  }

  if (thd->lock)
  {
    mysql_unlock_tables(thd, thd->lock);
    thd->lock=0;
  }
  /*
    assume handlers auto-commit (if some doesn't - transaction handling
    in MySQL should be redesigned to support it; it's a big change,
    and it's not worth it - better to commit explicitly only writing
    transactions, read-only ones should better take care of themselves.
    saves some work in 2pc too)
    see also sql_parse.cc - dispatch_command()
  */
  bzero(&thd->transaction.stmt, sizeof(thd->transaction.stmt));
  if (!thd->active_transaction())
    thd->transaction.xid.null();

  /* VOID(pthread_sigmask(SIG_SETMASK,&thd->block_signals,NULL)); */
  if (!lock_in_use)
    VOID(pthread_mutex_lock(&LOCK_open));
  safe_mutex_assert_owner(&LOCK_open);

  DBUG_PRINT("info", ("thd->open_tables: %p", thd->open_tables));

 found_old_table= 0;
  while (thd->open_tables != stopper)
    found_old_table|=close_thread_table(thd, &thd->open_tables);
  thd->some_tables_deleted=0;

  /* Free tables to hold down open files */
  while (open_cache.records > table_cache_size && unused_tables)
    VOID(hash_delete(&open_cache,(byte*) unused_tables)); /* purecov: tested */
  check_unused();
  if (found_old_table)
  {
    /* Tell threads waiting for refresh that something has happened */
    VOID(pthread_cond_broadcast(&COND_refresh));
  }
  if (!lock_in_use)
    VOID(pthread_mutex_unlock(&LOCK_open));
  /*  VOID(pthread_sigmask(SIG_SETMASK,&thd->signals,NULL)); */

  if (prelocked_mode == PRELOCKED)
  {
    /*
      If we are here then we are leaving normal prelocked mode, so it is
      good idea to turn off OPTION_TABLE_LOCK flag.
    */
    DBUG_ASSERT(thd->lex->requires_prelocking());
    thd->options&= ~(ulong) (OPTION_TABLE_LOCK);
  }

  DBUG_VOID_RETURN;
}

/* move one table to free list */

bool close_thread_table(THD *thd, TABLE **table_ptr)
{
  bool found_old_table= 0;
  TABLE *table= *table_ptr;
  DBUG_ENTER("close_thread_table");
  DBUG_ASSERT(table->key_read == 0);
  DBUG_ASSERT(table->file->inited == handler::NONE);

  *table_ptr=table->next;
  if (table->s->version != refresh_version ||
      thd->version != refresh_version || !table->db_stat)
  {
    VOID(hash_delete(&open_cache,(byte*) table));
    found_old_table=1;
  }
  else
  {
    if (table->s->flush_version != flush_version)
    {
      table->s->flush_version= flush_version;
      table->file->extra(HA_EXTRA_FLUSH);
    }
    else
    {
      // Free memory and reset for next loop
      table->file->reset();
    }
    table->in_use=0;
    if (unused_tables)
    {
      table->next=unused_tables;		/* Link in last */
      table->prev=unused_tables->prev;
      unused_tables->prev=table;
      table->prev->next=table;
    }
    else
      unused_tables=table->next=table->prev=table;
  }
  DBUG_RETURN(found_old_table);
}

	/* Close and delete temporary tables */

void close_temporary(TABLE *table,bool delete_table)
{
  DBUG_ENTER("close_temporary");
  char path[FN_REFLEN];
  db_type table_type=table->s->db_type;
  strmov(path,table->s->path);
  free_io_cache(table);
  closefrm(table);
  my_free((char*) table,MYF(0));
  if (delete_table)
    rm_temporary_table(table_type, path);
  DBUG_VOID_RETURN;
}


void close_temporary_tables(THD *thd)
{
  TABLE *table,*next;
  char *query, *end;
  uint query_buf_size; 
  bool found_user_tables = 0;

  if (!thd->temporary_tables)
    return;
  
  LINT_INIT(end);
  query_buf_size= 50;   // Enough for DROP ... TABLE IF EXISTS

  for (table=thd->temporary_tables ; table ; table=table->next)
    /*
      We are going to add 4 ` around the db/table names, so 1 does not look
      enough; indeed it is enough, because table->key_length is greater (by 8,
      because of server_id and thread_id) than db||table.
    */
    query_buf_size+= table->s->key_length+1;

  if ((query = alloc_root(thd->mem_root, query_buf_size)))
    // Better add "if exists", in case a RESET MASTER has been done
    end=strmov(query, "DROP /*!40005 TEMPORARY */ TABLE IF EXISTS ");

  for (table=thd->temporary_tables ; table ; table=next)
  {
    if (query) // we might be out of memory, but this is not fatal
    {
      // skip temporary tables not created directly by the user
      if (table->s->table_name[0] != '#')
	found_user_tables = 1;
      end = strxmov(end,"`",table->s->db,"`.`",
                    table->s->table_name,"`,", NullS);
    }
    next=table->next;
    close_temporary(table, 1);
  }
  if (query && found_user_tables && mysql_bin_log.is_open())
  {
    /* The -1 is to remove last ',' */
    thd->clear_error();
    Query_log_event qinfo(thd, query, (ulong)(end-query)-1, 0, FALSE);
    /*
      Imagine the thread had created a temp table, then was doing a SELECT, and
      the SELECT was killed. Then it's not clever to mark the statement above as
      "killed", because it's not really a statement updating data, and there
      are 99.99% chances it will succeed on slave.
      If a real update (one updating a persistent table) was killed on the
      master, then this real update will be logged with error_code=killed,
      rightfully causing the slave to stop.
    */
    qinfo.error_code= 0;
    mysql_bin_log.write(&qinfo);
  }
  thd->temporary_tables=0;
}


/*
  Find table in list.

  SYNOPSIS
    find_table_in_list()
    table		Pointer to table list
    offset		Offset to which list in table structure to use
    db_name		Data base name
    table_name		Table name

  NOTES:
    This is called by find_table_in_local_list() and
    find_table_in_global_list().

  RETURN VALUES
    NULL	Table not found
    #		Pointer to found table.
*/

TABLE_LIST *find_table_in_list(TABLE_LIST *table,
                               uint offset,
                               const char *db_name,
                               const char *table_name)
{
  for (; table; table= *(TABLE_LIST **) ((char*) table + offset))
  {
    if ((table->table == 0 || table->table->s->tmp_table == NO_TMP_TABLE) &&
        strcmp(table->db, db_name) == 0 &&
        strcmp(table->table_name, table_name) == 0)
      break;
  }
  return table;
}


/*
  Test that table is unique (It's only exists once in the table list)

  SYNOPSIS
    unique_table()
    table                 table which should be checked
    table_list            list of tables

  NOTE: to exclude derived tables from check we use following mechanism:
    a) during derived table processing set THD::derived_tables_processing
    b) JOIN::prepare set SELECT::exclude_from_table_unique_test if
       THD::derived_tables_processing set. (we can't use JOIN::execute
       because for PS we perform only JOIN::prepare, but we can't set this
       flag in JOIN::prepare if we are not sure that we are in derived table
       processing loop, because multi-update call fix_fields() for some its
       items (which mean JOIN::prepare for subqueries) before unique_table
       call to detect which tables should be locked for write).
    c) unique_table skip all tables which belong to SELECT with
       SELECT::exclude_from_table_unique_test set.
    Also SELECT::exclude_from_table_unique_test used to exclude from check
    tables of main SELECT of multi-delete and multi-update

    TODO: when we will have table/view change detection we can do this check
          only once for PS/SP

  RETURN
    found duplicate
    0 if table is unique
*/

TABLE_LIST* unique_table(TABLE_LIST *table, TABLE_LIST *table_list)
{
  TABLE_LIST *res;
  const char *d_name, *t_name;
  DBUG_ENTER("unique_table");
  DBUG_PRINT("enter", ("table alias: %s", table->alias));

  /*
    If this function called for query which update table (INSERT/UPDATE/...)
    then we have in table->table pointer to TABLE object which we are
    updating even if it is VIEW so we need TABLE_LIST of this TABLE object
    to get right names (even if lower_case_table_names used).

    If this function called for CREATE command that we have not opened table
    (table->table equal to 0) and right names is in current TABLE_LIST
    object.
  */
  if (table->table)
  {
    /* temporary table is always unique */
    if (table->table && table->table->s->tmp_table != NO_TMP_TABLE)
      DBUG_RETURN(0);
    table= table->find_underlying_table(table->table);
    /*
      as far as we have table->table we have to find real TABLE_LIST of
      it in underlying tables
    */
    DBUG_ASSERT(table);
  }
  d_name= table->db;
  t_name= table->table_name;

  DBUG_PRINT("info", ("real table: %s.%s", d_name, t_name));
  for (;;)
  {
    if (!(res= find_table_in_global_list(table_list, d_name, t_name)) ||
        (!res->table || res->table != table->table) &&
        (res->select_lex && !res->select_lex->exclude_from_table_unique_test))
      break;
    /*
      If we found entry of this table or or table of SELECT which already
      processed in derived table or top select of multi-update/multi-delete
      (exclude_from_table_unique_test).
    */
    table_list= res->next_global;
    DBUG_PRINT("info",
               ("found same copy of table or table which we should skip"));
  }
  DBUG_RETURN(res);
}


TABLE **find_temporary_table(THD *thd, const char *db, const char *table_name)
{
  char	key[MAX_DBKEY_LENGTH];
  uint	key_length= (uint) (strmov(strmov(key,db)+1,table_name)-key)+1;
  TABLE *table,**prev;

  int4store(key+key_length,thd->server_id);
  key_length += 4;
  int4store(key+key_length,thd->variables.pseudo_thread_id);
  key_length += 4;

  prev= &thd->temporary_tables;
  for (table=thd->temporary_tables ; table ; table=table->next)
  {
    if (table->s->key_length == key_length &&
	!memcmp(table->s->table_cache_key,key,key_length))
      return prev;
    prev= &table->next;
  }
  return 0;					// Not a temporary table
}

bool close_temporary_table(THD *thd, const char *db, const char *table_name)
{
  TABLE *table,**prev;

  if (!(prev=find_temporary_table(thd,db,table_name)))
    return 1;
  table= *prev;
  *prev= table->next;
  close_temporary(table, 1);
  if (thd->slave_thread)
    --slave_open_temp_tables;
  return 0;
}

/*
  Used by ALTER TABLE when the table is a temporary one. It changes something
  only if the ALTER contained a RENAME clause (otherwise, table_name is the old
  name).
  Prepares a table cache key, which is the concatenation of db, table_name and
  thd->slave_proxy_id, separated by '\0'.
*/

bool rename_temporary_table(THD* thd, TABLE *table, const char *db,
			    const char *table_name)
{
  char *key;
  TABLE_SHARE *share= table->s;

  if (!(key=(char*) alloc_root(&table->mem_root,
			       (uint) strlen(db)+
			       (uint) strlen(table_name)+6+4)))
    return 1;				/* purecov: inspected */
  share->key_length= (uint)
    (strmov((char*) (share->table_name= strmov(share->table_cache_key= key,
                                               db)+1),
	    table_name) - share->table_cache_key)+1;
  share->db= share->table_cache_key;
  int4store(key+share->key_length, thd->server_id);
  share->key_length+= 4;
  int4store(key+share->key_length, thd->variables.pseudo_thread_id);
  share->key_length+= 4;
  return 0;
}


	/* move table first in unused links */

static void relink_unused(TABLE *table)
{
  if (table != unused_tables)
  {
    table->prev->next=table->next;		/* Remove from unused list */
    table->next->prev=table->prev;
    table->next=unused_tables;			/* Link in unused tables */
    table->prev=unused_tables->prev;
    unused_tables->prev->next=table;
    unused_tables->prev=table;
    unused_tables=table;
    check_unused();
  }
}


/*
  Remove all instances of table from the current open list
  Free all locks on tables that are done with LOCK TABLES
 */

TABLE *unlink_open_table(THD *thd, TABLE *list, TABLE *find)
{
  char key[MAX_DBKEY_LENGTH];
  uint key_length= find->s->key_length;
  TABLE *start=list,**prev,*next;
  prev= &start;

  memcpy(key, find->s->table_cache_key, key_length);
  for (; list ; list=next)
  {
    next=list->next;
    if (list->s->key_length == key_length &&
	!memcmp(list->s->table_cache_key, key, key_length))
    {
      if (thd->locked_tables)
	mysql_lock_remove(thd, thd->locked_tables,list);
      VOID(hash_delete(&open_cache,(byte*) list)); // Close table
    }
    else
    {
      *prev=list;				// put in use list
      prev= &list->next;
    }
  }
  *prev=0;
  // Notify any 'refresh' threads
  pthread_cond_broadcast(&COND_refresh);
  return start;
}


/*
   When we call the following function we must have a lock on
   LOCK_open ; This lock will be unlocked on return.
*/

void wait_for_refresh(THD *thd)
{
  safe_mutex_assert_owner(&LOCK_open);

  /* Wait until the current table is up to date */
  const char *proc_info;
  thd->mysys_var->current_mutex= &LOCK_open;
  thd->mysys_var->current_cond= &COND_refresh;
  proc_info=thd->proc_info;
  thd->proc_info="Waiting for table";
  if (!thd->killed)
    (void) pthread_cond_wait(&COND_refresh,&LOCK_open);

  pthread_mutex_unlock(&LOCK_open);	// Must be unlocked first
  pthread_mutex_lock(&thd->mysys_var->mutex);
  thd->mysys_var->current_mutex= 0;
  thd->mysys_var->current_cond= 0;
  thd->proc_info= proc_info;
  pthread_mutex_unlock(&thd->mysys_var->mutex);
}


TABLE *reopen_name_locked_table(THD* thd, TABLE_LIST* table_list)
{
  DBUG_ENTER("reopen_name_locked_table");
  if (thd->killed)
    DBUG_RETURN(0);
  TABLE *table;
  TABLE_SHARE *share;
  if (!(table = table_list->table))
    DBUG_RETURN(0);

  char* db = thd->db ? thd->db : table_list->db;
  char* table_name = table_list->table_name;
  char	key[MAX_DBKEY_LENGTH];
  uint	key_length;
  key_length=(uint) (strmov(strmov(key,db)+1,table_name)-key)+1;

  pthread_mutex_lock(&LOCK_open);
  if (open_unireg_entry(thd, table, db, table_name, table_name, 0,
                        thd->mem_root) ||
      !(table->s->table_cache_key= memdup_root(&table->mem_root, (char*) key,
                                               key_length)))
  {
    delete table->triggers;
    closefrm(table);
    pthread_mutex_unlock(&LOCK_open);
    DBUG_RETURN(0);
  }

  share= table->s;
  share->db= share->table_cache_key;
  share->key_length=key_length;
  share->version=0;
  share->flush_version=0;
  table->in_use = thd;
  check_unused();
  pthread_mutex_unlock(&LOCK_open);
  table->next = thd->open_tables;
  thd->open_tables = table;
  table->tablenr=thd->current_tablenr++;
  table->used_fields=0;
  table->const_table=0;
  table->null_row= table->maybe_null= table->force_index= 0;
  table->status=STATUS_NO_RECORD;
  table->keys_in_use_for_query= share->keys_in_use;
  table->used_keys= share->keys_for_keyread;
  DBUG_RETURN(table);
}


/*
  Open a table.

  SYNOPSIS
    open_table()
      thd         Thread context
      table_list  Open first table in list
      refresh     Pointer to memory that will be set to 1 if
                  we need to close all tables and reopen them
                  If this is a NULL pointer, then the is no version
                  number checking and the table is not put in the
                  thread-open-list
      flags       Bitmap of flags to modify how open works:
                    MYSQL_LOCK_IGNORE_FLUSH - Open table even if someone
                    has done a flush or namelock on it.

  IMPLEMENTATION
    Uses a cache of open tables to find a table not in use.

  RETURN
    NULL  Open failed.  If refresh is set then one should close
          all other tables and retry the open
    #     Success. Pointer to TABLE object for open table.
*/


TABLE *open_table(THD *thd, TABLE_LIST *table_list, MEM_ROOT *mem_root,
		  bool *refresh, uint flags)
{
  reg1	TABLE *table;
  char	key[MAX_DBKEY_LENGTH];
  uint	key_length;
  char	*alias= table_list->alias;
  DBUG_ENTER("open_table");

  /* find a unused table in the open table cache */
  if (refresh)
    *refresh=0;
  if (thd->killed)
    DBUG_RETURN(0);
  key_length= (uint) (strmov(strmov(key, table_list->db)+1,
			     table_list->table_name)-key)+1;
  int4store(key + key_length, thd->server_id);
  int4store(key + key_length + 4, thd->variables.pseudo_thread_id);

  if (!table_list->skip_temporary)
  {
    for (table= thd->temporary_tables; table ; table=table->next)
    {
      if (table->s->key_length == key_length + TMP_TABLE_KEY_EXTRA &&
	  !memcmp(table->s->table_cache_key, key,
		  key_length + TMP_TABLE_KEY_EXTRA))
      {
	if (table->query_id == thd->query_id ||
            thd->prelocked_mode && table->query_id)
	{
	  my_error(ER_CANT_REOPEN_TABLE, MYF(0), table->alias);
	  DBUG_RETURN(0);
	}
	table->query_id= thd->query_id;
	table->clear_query_id= 1;
	thd->tmp_table_used= 1;
        DBUG_PRINT("info",("Using temporary table"));
        goto reset;
      }
    }
  }

  if (thd->locked_tables || thd->prelocked_mode)
  {						// Using table locks
    TABLE *best_table= 0;
    int best_distance= INT_MIN;
    for (table=thd->open_tables; table ; table=table->next)
    {
      if (table->s->key_length == key_length &&
          !memcmp(table->s->table_cache_key, key, key_length) &&
          !my_strcasecmp(system_charset_info, table->alias, alias) &&
          table->query_id != thd->query_id && /* skip tables already used */
          !(thd->prelocked_mode && table->query_id))
      {
        int distance= ((int) table->reginfo.lock_type -
                       (int) table_list->lock_type);
        /*
          Find a table that either has the exact lock type requested,
          or has the best suitable lock. In case there is no locked
          table that has an equal or higher lock than requested,
          we us the closest matching lock to be able to produce an error
          message about wrong lock mode on the table. The best_table is changed
          if bd < 0 <= d or bd < d < 0 or 0 <= d < bd.

          distance <  0 - No suitable lock found
          distance >  0 - we have lock mode higher then we require
          distance == 0 - we have lock mode exactly which we need
        */
        if (best_distance < 0 && distance > best_distance ||
            distance >= 0 && distance < best_distance)
        {
          best_distance= distance;
          best_table= table;
          if (best_distance == 0)               // Found perfect lock
            break;
        }
      }
    }
    if (best_table)
    {
      table= best_table;
      table->query_id= thd->query_id;
      DBUG_PRINT("info",("Using locked table"));
      goto reset;
    }
    /*
      is it view?
      (it is work around to allow to open view with locked tables,
      real fix will be made after definition cache will be made)
    */
    {
      char path[FN_REFLEN];
      strxnmov(path, FN_REFLEN, mysql_data_home, "/", table_list->db, "/",
               table_list->table_name, reg_ext, NullS);
      (void) unpack_filename(path, path);
      if (mysql_frm_type(path) == FRMTYPE_VIEW)
      {
        TABLE tab;// will not be used (because it's VIEW) but have to be passed
        table= &tab;
        VOID(pthread_mutex_lock(&LOCK_open));
        if (open_unireg_entry(thd, table, table_list->db,
                              table_list->table_name,
                              alias, table_list, mem_root))
        {
          table->next=table->prev=table;
          free_cache_entry(table);
        }
        else
        {
          DBUG_ASSERT(table_list->view != 0);
          VOID(pthread_mutex_unlock(&LOCK_open));
          DBUG_RETURN(0); // VIEW
        }
        VOID(pthread_mutex_unlock(&LOCK_open));
      }
    }
    my_error(ER_TABLE_NOT_LOCKED, MYF(0), alias);
    DBUG_RETURN(0);
  }

  VOID(pthread_mutex_lock(&LOCK_open));

  if (!thd->open_tables)
    thd->version=refresh_version;
  else if (thd->version != refresh_version && refresh)
  {
    /* Someone did a refresh while thread was opening tables */
    *refresh=1;
    VOID(pthread_mutex_unlock(&LOCK_open));
    DBUG_RETURN(0);
  }

  /* close handler tables which are marked for flush */
  if (thd->handler_tables)
    mysql_ha_flush(thd, (TABLE_LIST*) NULL, MYSQL_HA_REOPEN_ON_USAGE);

  for (table=(TABLE*) hash_search(&open_cache,(byte*) key,key_length) ;
       table && table->in_use ;
       table = (TABLE*) hash_next(&open_cache,(byte*) key,key_length))
  {
    if (table->s->version != refresh_version)
    {
      if (flags & MYSQL_LOCK_IGNORE_FLUSH)
      {
        /* Force close at once after usage */
        thd->version= table->s->version;
        continue;
      }

      /*
        There is a refresh in progress for this table
        Wait until the table is freed or the thread is killed.
      */
      close_old_data_files(thd,thd->open_tables,0,0);
      if (table->in_use != thd)
	wait_for_refresh(thd);
      else
      {
	VOID(pthread_mutex_unlock(&LOCK_open));
      }
      if (refresh)
	*refresh=1;
      DBUG_RETURN(0);
    }
  }
  if (table)
  {
    if (table == unused_tables)
    {						// First unused
      unused_tables=unused_tables->next;	// Remove from link
      if (table == unused_tables)
	unused_tables=0;
    }
    table->prev->next=table->next;		/* Remove from unused list */
    table->next->prev=table->prev;
    table->in_use= thd;
  }
  else
  {
    TABLE_SHARE *share;
    /* Free cache if too big */
    while (open_cache.records > table_cache_size && unused_tables)
      VOID(hash_delete(&open_cache,(byte*) unused_tables)); /* purecov: tested */

    /* make a new table */
    if (!(table=(TABLE*) my_malloc(sizeof(*table),MYF(MY_WME))))
    {
      VOID(pthread_mutex_unlock(&LOCK_open));
      DBUG_RETURN(NULL);
    }
    if (open_unireg_entry(thd, table, table_list->db, table_list->table_name,
			  alias, table_list, mem_root) ||
	(!table_list->view && 
	 !(table->s->table_cache_key= memdup_root(&table->mem_root,
                                                  (char*) key,
                                                  key_length))))
    {
      table->next=table->prev=table;
      free_cache_entry(table);
      VOID(pthread_mutex_unlock(&LOCK_open));
      DBUG_RETURN(NULL);
    }
    if (table_list->view)
    {
      my_free((gptr)table, MYF(0));
      VOID(pthread_mutex_unlock(&LOCK_open));
      DBUG_RETURN(0); // VIEW
    }
    share= table->s;
    share->db=            share->table_cache_key;
    share->key_length=    key_length;
    share->version=       refresh_version;
    share->flush_version= flush_version;
    DBUG_PRINT("info", ("inserting table %p into the cache", table));
    VOID(my_hash_insert(&open_cache,(byte*) table));
  }

  check_unused();				// Debugging call

  VOID(pthread_mutex_unlock(&LOCK_open));
  if (refresh)
  {
    table->next=thd->open_tables;		/* Link into simple list */
    thd->open_tables=table;
  }
  table->reginfo.lock_type=TL_READ;		/* Assume read */

 reset:
  if (thd->lex->need_correct_ident())
    table->alias_name_used= my_strcasecmp(table_alias_charset,
                                          table->s->table_name, alias);
  /* Fix alias if table name changes */
  if (strcmp(table->alias, alias))
  {
    uint length=(uint) strlen(alias)+1;
    table->alias= (char*) my_realloc((char*) table->alias, length,
                                     MYF(MY_WME));
    memcpy((char*) table->alias, alias, length);
  }
  /* These variables are also set in reopen_table() */
  table->tablenr=thd->current_tablenr++;
  table->used_fields=0;
  table->const_table=0;
  table->null_row= table->maybe_null= table->force_index= 0;
  table->status=STATUS_NO_RECORD;
  table->keys_in_use_for_query= table->s->keys_in_use;
  table->insert_values= 0;
  table->used_keys= table->s->keys_for_keyread;
  if (table->timestamp_field)
    table->timestamp_field_type= table->timestamp_field->get_auto_set_type();
  table_list->updatable= 1; // It is not derived table nor non-updatable VIEW
  DBUG_ASSERT(table->key_read == 0);
  DBUG_RETURN(table);
}


TABLE *find_locked_table(THD *thd, const char *db,const char *table_name)
{
  char	key[MAX_DBKEY_LENGTH];
  uint key_length=(uint) (strmov(strmov(key,db)+1,table_name)-key)+1;

  for (TABLE *table=thd->open_tables; table ; table=table->next)
  {
    if (table->s->key_length == key_length &&
	!memcmp(table->s->table_cache_key,key,key_length))
      return table;
  }
  return(0);
}


/****************************************************************************
** Reopen an table because the definition has changed. The date file for the
** table is already closed.
** Returns 0 if ok.
** If table can't be reopened, the entry is unchanged.
****************************************************************************/

bool reopen_table(TABLE *table,bool locked)
{
  TABLE tmp;
  char *db= table->s->table_cache_key;
  const char *table_name= table->s->table_name;
  bool error= 1;
  Field **field;
  uint key,part;
  DBUG_ENTER("reopen_table");

#ifdef EXTRA_DEBUG
  if (table->db_stat)
    sql_print_error("Table %s had a open data handler in reopen_table",
		    table->alias);
#endif
  if (!locked)
    VOID(pthread_mutex_lock(&LOCK_open));
  safe_mutex_assert_owner(&LOCK_open);

  if (open_unireg_entry(table->in_use, &tmp, db, table_name,
			table->alias, 0, table->in_use->mem_root))
    goto end;
  free_io_cache(table);

  if (!(tmp.s->table_cache_key= memdup_root(&tmp.mem_root,db,
                                            table->s->key_length)))
  {
    delete tmp.triggers;
    closefrm(&tmp);				// End of memory
    goto end;
  }
  tmp.s->db= tmp.s->table_cache_key;

  /* This list copies variables set by open_table */
  tmp.tablenr=		table->tablenr;
  tmp.used_fields=	table->used_fields;
  tmp.const_table=	table->const_table;
  tmp.null_row=		table->null_row;
  tmp.maybe_null=	table->maybe_null;
  tmp.status=		table->status;
  tmp.keys_in_use_for_query= tmp.s->keys_in_use;
  tmp.used_keys= 	tmp.s->keys_for_keyread;
  tmp.force_index=	tmp.force_index;

  /* Get state */
  tmp.s->key_length=	table->s->key_length;
  tmp.in_use=    	table->in_use;
  tmp.reginfo.lock_type=table->reginfo.lock_type;
  tmp.s->version=	refresh_version;
  tmp.s->tmp_table=	table->s->tmp_table;
  tmp.grant=		table->grant;

  /* Replace table in open list */
  tmp.next=		table->next;
  tmp.prev=		table->prev;

  delete table->triggers;
  if (table->file)
    VOID(closefrm(table));		// close file, free everything

  *table= tmp;
  table->s= &table->share_not_to_be_used;
  table->file->change_table_ptr(table);

  DBUG_ASSERT(table->alias != 0);
  for (field=table->field ; *field ; field++)
  {
    (*field)->table= (*field)->orig_table= table;
    (*field)->table_name= &table->alias;
  }
  for (key=0 ; key < table->s->keys ; key++)
    for (part=0 ; part < table->key_info[key].usable_key_parts ; part++)
      table->key_info[key].key_part[part].field->table= table;
  VOID(pthread_cond_broadcast(&COND_refresh));
  error=0;

 end:
  if (!locked)
    VOID(pthread_mutex_unlock(&LOCK_open));
  DBUG_RETURN(error);
}


/*
  Used with ALTER TABLE:
  Close all instanses of table when LOCK TABLES is in used;
  Close first all instances of table and then reopen them
 */

bool close_data_tables(THD *thd,const char *db, const char *table_name)
{
  TABLE *table;
  for (table=thd->open_tables; table ; table=table->next)
  {
    if (!strcmp(table->s->table_name, table_name) &&
	!strcmp(table->s->db, db))
    {
      mysql_lock_remove(thd, thd->locked_tables,table);
      table->file->close();
      table->db_stat=0;
    }
  }
  return 0;					// For the future
}


/*
  Reopen all tables with closed data files
  One should have lock on LOCK_open when calling this
*/

bool reopen_tables(THD *thd,bool get_locks,bool in_refresh)
{
  DBUG_ENTER("reopen_tables");
  safe_mutex_assert_owner(&LOCK_open);

  if (!thd->open_tables)
    DBUG_RETURN(0);

  TABLE *table,*next,**prev;
  TABLE **tables,**tables_ptr;			// For locks
  bool error=0;
  if (get_locks)
  {
    /* The ptr is checked later */
    uint opens=0;
    for (table=thd->open_tables; table ; table=table->next) opens++;
    tables= (TABLE**) my_alloca(sizeof(TABLE*)*opens);
  }
  else
    tables= &thd->open_tables;
  tables_ptr =tables;

  prev= &thd->open_tables;
  for (table=thd->open_tables; table ; table=next)
  {
    uint db_stat=table->db_stat;
    next=table->next;
    if (!tables || (!db_stat && reopen_table(table,1)))
    {
      my_error(ER_CANT_REOPEN_TABLE, MYF(0), table->alias);
      VOID(hash_delete(&open_cache,(byte*) table));
      error=1;
    }
    else
    {
      *prev= table;
      prev= &table->next;
      if (get_locks && !db_stat)
	*tables_ptr++= table;			// need new lock on this
      if (in_refresh)
      {
	table->s->version=0;
	table->locked_by_flush=0;
      }
    }
  }
  if (tables != tables_ptr)			// Should we get back old locks
  {
    MYSQL_LOCK *lock;
    /* We should always get these locks */
    thd->some_tables_deleted=0;
    if ((lock= mysql_lock_tables(thd, tables, (uint) (tables_ptr - tables), 0)))
    {
      thd->locked_tables=mysql_lock_merge(thd->locked_tables,lock);
    }
    else
      error=1;
  }
  if (get_locks && tables)
  {
    my_afree((gptr) tables);
  }
  VOID(pthread_cond_broadcast(&COND_refresh)); // Signal to refresh
  *prev=0;
  DBUG_RETURN(error);
}

/*
  Close handlers for tables in list, but leave the TABLE structure
  intact so that we can re-open these quickly
  abort_locks is set if called from flush_tables.
*/

void close_old_data_files(THD *thd, TABLE *table, bool abort_locks,
			  bool send_refresh)
{
  DBUG_ENTER("close_old_data_files");
  bool found=send_refresh;
  for (; table ; table=table->next)
  {
    if (table->s->version != refresh_version)
    {
      found=1;
      if (!abort_locks)				// If not from flush tables
	table->s->version= refresh_version;	// Let other threads use table
      if (table->db_stat)
      {
	if (abort_locks)
	{
	  mysql_lock_abort(thd,table);		// Close waiting threads
	  mysql_lock_remove(thd, thd->locked_tables,table);
	  table->locked_by_flush=1;		// Will be reopened with locks
	}
	table->file->close();
	table->db_stat=0;
      }
    }
  }
  if (found)
    VOID(pthread_cond_broadcast(&COND_refresh)); // Signal to refresh
  DBUG_VOID_RETURN;
}


/*
  Wait until all threads has closed the tables in the list
  We have also to wait if there is thread that has a lock on this table even
  if the table is closed
*/

bool table_is_used(TABLE *table, bool wait_for_name_lock)
{
  do
  {
    char *key= table->s->table_cache_key;
    uint key_length= table->s->key_length;
    for (TABLE *search=(TABLE*) hash_search(&open_cache,
					    (byte*) key,key_length) ;
	 search ;
	 search = (TABLE*) hash_next(&open_cache,(byte*) key,key_length))
    {
      if (search->locked_by_flush ||
	  search->locked_by_name && wait_for_name_lock ||
	  search->db_stat && search->s->version < refresh_version)
	return 1;				// Table is used
    }
  } while ((table=table->next));
  return 0;
}


/* Wait until all used tables are refreshed */

bool wait_for_tables(THD *thd)
{
  bool result;
  DBUG_ENTER("wait_for_tables");

  thd->proc_info="Waiting for tables";
  pthread_mutex_lock(&LOCK_open);
  while (!thd->killed)
  {
    thd->some_tables_deleted=0;
    close_old_data_files(thd,thd->open_tables,0,dropping_tables != 0);
    mysql_ha_flush(thd, (TABLE_LIST*) NULL, MYSQL_HA_REOPEN_ON_USAGE);
    if (!table_is_used(thd->open_tables,1))
      break;
    (void) pthread_cond_wait(&COND_refresh,&LOCK_open);
  }
  if (thd->killed)
    result= 1;					// aborted
  else
  {
    /* Now we can open all tables without any interference */
    thd->proc_info="Reopen tables";
    thd->version= refresh_version;
    result=reopen_tables(thd,0,0);
  }
  pthread_mutex_unlock(&LOCK_open);
  thd->proc_info=0;
  DBUG_RETURN(result);
}


/* drop tables from locked list */

bool drop_locked_tables(THD *thd,const char *db, const char *table_name)
{
  TABLE *table,*next,**prev;
  bool found=0;
  prev= &thd->open_tables;
  for (table= thd->open_tables; table ; table=next)
  {
    next=table->next;
    if (!strcmp(table->s->table_name, table_name) &&
	!strcmp(table->s->db, db))
    {
      mysql_lock_remove(thd, thd->locked_tables,table);
      VOID(hash_delete(&open_cache,(byte*) table));
      found=1;
    }
    else
    {
      *prev=table;
      prev= &table->next;
    }
  }
  *prev=0;
  if (found)
    VOID(pthread_cond_broadcast(&COND_refresh)); // Signal to refresh
  if (thd->locked_tables && thd->locked_tables->table_count == 0)
  {
    my_free((gptr) thd->locked_tables,MYF(0));
    thd->locked_tables=0;
  }
  return found;
}


/*
  If we have the table open, which only happens when a LOCK TABLE has been
  done on the table, change the lock type to a lock that will abort all
  other threads trying to get the lock.
*/

void abort_locked_tables(THD *thd,const char *db, const char *table_name)
{
  TABLE *table;
  for (table= thd->open_tables; table ; table= table->next)
  {
    if (!strcmp(table->s->table_name,table_name) &&
	!strcmp(table->s->db, db))
    {
      mysql_lock_abort(thd,table);
      break;
    }
  }
}


/*
  Load a table definition from file and open unireg table

  SYNOPSIS
    open_unireg_entry()
    thd			Thread handle
    entry		Store open table definition here
    db			Database name
    name		Table name
    alias		Alias name
    table_desc		TABLE_LIST descriptor (used with views)
    mem_root		temporary mem_root for parsing

  NOTES
   Extra argument for open is taken from thd->open_options

  RETURN
    0	ok
    #	Error
*/
static int open_unireg_entry(THD *thd, TABLE *entry, const char *db,
			     const char *name, const char *alias,
			     TABLE_LIST *table_desc, MEM_ROOT *mem_root)
{
  char path[FN_REFLEN];
  int error;
  uint discover_retry_count= 0;
  DBUG_ENTER("open_unireg_entry");

  strxmov(path, mysql_data_home, "/", db, "/", name, NullS);
  while ((error= openfrm(thd, path, alias,
		         (uint) (HA_OPEN_KEYFILE | HA_OPEN_RNDFILE |
			         HA_GET_INDEX | HA_TRY_READ_ONLY |
                                 NO_ERR_ON_NEW_FRM),
		      READ_KEYINFO | COMPUTE_TYPES | EXTRA_RECORD,
		      thd->open_options, entry)) &&
      (error != 5 ||
       (fn_format(path, path, 0, reg_ext, MY_UNPACK_FILENAME),
        open_new_frm(path, alias, db, name,
                     (uint) (HA_OPEN_KEYFILE | HA_OPEN_RNDFILE |
                             HA_GET_INDEX | HA_TRY_READ_ONLY),
                     READ_KEYINFO | COMPUTE_TYPES | EXTRA_RECORD,
                     thd->open_options, entry, table_desc, mem_root))))

  {
    if (!entry->s || !entry->s->crashed)
    {
      /*
        Frm file could not be found on disk
        Since it does not exist, no one can be using it
        LOCK_open has been locked to protect from someone else
        trying to discover the table at the same time.
      */
      if (discover_retry_count++ != 0)
        goto err;
      if (ha_create_table_from_engine(thd, db, name) > 0)
      {
        /* Give right error message */
        thd->clear_error();
        DBUG_PRINT("error", ("Dicovery of %s/%s failed", db, name));
        my_printf_error(ER_UNKNOWN_ERROR,
                        "Failed to open '%-.64s', error while "
                        "unpacking from engine",
                        MYF(0), name);

        goto err;
      }

      mysql_reset_errors(thd, 1);    // Clear warnings
      thd->clear_error();            // Clear error message
      continue;
    }

    // Code below is for repairing a crashed file
    TABLE_LIST table_list;
    bzero((char*) &table_list, sizeof(table_list)); // just for safe
    table_list.db=(char*) db;
    table_list.table_name=(char*) name;

    safe_mutex_assert_owner(&LOCK_open);

    if ((error=lock_table_name(thd,&table_list)))
    {
      if (error < 0)
      {
	goto err;
      }
      if (wait_for_locked_table_names(thd,&table_list))
      {
	unlock_table_name(thd,&table_list);
	goto err;
      }
    }
    pthread_mutex_unlock(&LOCK_open);
    thd->clear_error();				// Clear error message
    error= 0;
    if (openfrm(thd, path, alias,
		(uint) (HA_OPEN_KEYFILE | HA_OPEN_RNDFILE | HA_GET_INDEX |
			 HA_TRY_READ_ONLY),
		READ_KEYINFO | COMPUTE_TYPES | EXTRA_RECORD,
		ha_open_options | HA_OPEN_FOR_REPAIR,
		entry) || ! entry->file ||
	(entry->file->is_crashed() && entry->file->check_and_repair(thd)))
    {
      /* Give right error message */
      thd->clear_error();
      my_error(ER_NOT_KEYFILE, MYF(0), name, my_errno);
      sql_print_error("Couldn't repair table: %s.%s",db,name);
      if (entry->file)
	closefrm(entry);
      error=1;
    }
    else
      thd->clear_error();			// Clear error message
    pthread_mutex_lock(&LOCK_open);
    unlock_table_name(thd,&table_list);

    if (error)
      goto err;
    break;
  }

  if (error == 5)
    DBUG_RETURN(0);	// we have just opened VIEW

  /*
    We can't mark all tables in 'mysql' database as system since we don't
    allow to lock such tables for writing with any other tables (even with
    other system tables) and some privilege tables need this.
  */
  if (!my_strcasecmp(system_charset_info, db, "mysql") &&
      !my_strcasecmp(system_charset_info, name, "proc"))
    entry->s->system_table= 1;

  if (Table_triggers_list::check_n_load(thd, db, name, entry, 0))
    goto err;

  /*
    If we are here, there was no fatal error (but error may be still
    unitialized).
  */
  if (unlikely(entry->file->implicit_emptied))
  {
    entry->file->implicit_emptied= 0;
    if (mysql_bin_log.is_open())
    {
      char *query, *end;
      uint query_buf_size= 20 + 2*NAME_LEN + 1;
      if ((query= (char*)my_malloc(query_buf_size,MYF(MY_WME))))
      {
        end = strxmov(strmov(query, "DELETE FROM `"),
                      db,"`.`",name,"`", NullS);
        Query_log_event qinfo(thd, query, (ulong)(end-query), 0, FALSE);
        mysql_bin_log.write(&qinfo);
        my_free(query, MYF(0));
      }
      else
      {
        /*
          As replication is maybe going to be corrupted, we need to warn the
          DBA on top of warning the client (which will automatically be done
          because of MYF(MY_WME) in my_malloc() above).
        */
        sql_print_error("When opening HEAP table, could not allocate \
memory to write 'DELETE FROM `%s`.`%s`' to the binary log",db,name);
        delete entry->triggers;
        if (entry->file)
          closefrm(entry);
        goto err;
      }
    }
  }
  DBUG_RETURN(0);
err:
  /* Hide "Table doesn't exist" errors if table belong to view */
  if (thd->net.last_errno == ER_NO_SUCH_TABLE &&
      table_desc && table_desc->belong_to_view)
  {
    TABLE_LIST * view= table_desc->belong_to_view;
    thd->clear_error();
    my_error(ER_VIEW_INVALID, MYF(0), view->view_db.str, view->view_name.str);
  }
  DBUG_RETURN(1);
}

/*
  Open all tables in list

  SYNOPSIS
    open_tables()
    thd - thread handler
    start - list of tables in/out
    counter - number of opened tables will be return using this parameter

  NOTE
    Unless we are already in prelocked mode, this function will also precache
    all SP/SFs explicitly or implicitly (via views and triggers) used by the
    query and add tables needed for their execution to table list. If resulting
    tables list will be non empty it will mark query as requiring precaching.
    Prelocked mode will be enabled for such query during lock_tables() call.

    If query for which we are opening tables is already marked as requiring
    prelocking it won't do such precaching and will simply reuse table list
    which is already built.

  RETURN
    0  - OK
    -1 - error
*/

int open_tables(THD *thd, TABLE_LIST **start, uint *counter)
{
  TABLE_LIST *tables;
  bool refresh;
  int result=0;
  MEM_ROOT new_frm_mem;
  /* Also used for indicating that prelocking is need */
  TABLE_LIST **query_tables_last_own;
  DBUG_ENTER("open_tables");
  /*
    temporary mem_root for new .frm parsing.
    TODO: variables for size
  */
  init_alloc_root(&new_frm_mem, 8024, 8024);

  thd->current_tablenr= 0;
 restart:
  *counter= 0;
  query_tables_last_own= 0;
  thd->proc_info="Opening tables";

  /*
    If we are not already executing prelocked statement and don't have
    statement for which table list for prelocking is already built, let
    us cache routines and try to build such table list.

    NOTE: If we want queries with functions to work under explicit
    LOCK TABLES we have to additionaly lock mysql.proc table in it.
    At least until Monty will fix SP loading :)

    NOTE: We can't delay prelocking until we will met some sub-statement
    which really uses tables, since this will imply that we have to restore
    its table list to be able execute it in some other context.
    And current views implementation assumes that view tables are added to
    global table list only once during PS preparing/first SP execution.
    Also locking at earlier stage is probably faster altough may decrease
    concurrency a bit.

    NOTE: We will mark statement as requiring prelocking only if we will
    have non empty table list. But this does not guarantee that in prelocked
    mode we will have some locked tables, because queries which use only
    derived/information schema tables and views possible. Thus "counter"
    may be still zero for prelocked statement...
  */
  if (!thd->prelocked_mode && !thd->lex->requires_prelocking() &&
      thd->lex->sroutines.records)
  {
    TABLE_LIST **save_query_tables_last= thd->lex->query_tables_last;

    DBUG_ASSERT(thd->lex->query_tables == *start);

    if (sp_cache_routines_and_add_tables(thd, thd->lex) ||
        *start)
    {
      query_tables_last_own= save_query_tables_last;
      *start= thd->lex->query_tables;
    }
  }

  for (tables= *start; tables ;tables= tables->next_global)
  {
    /*
      Ignore placeholders for derived tables. After derived tables
      processing, link to created temporary table will be put here.
     */
    if (tables->derived)
      continue;
    if (tables->schema_table)
    {
      if (!mysql_schema_table(thd, thd->lex, tables))
        continue;
      DBUG_RETURN(-1);
    }
    (*counter)++;
    if (!tables->table &&
	!(tables->table= open_table(thd, tables, &new_frm_mem, &refresh, 0)))
    {
      free_root(&new_frm_mem, MYF(MY_KEEP_PREALLOC));
      if (tables->view)
      {
        /* VIEW placeholder */
	(*counter)--;
        /*
          Again if needed we have to get cache all routines used by this view
          and add tables used by them to table list.
        */
        if (!thd->prelocked_mode && !thd->lex->requires_prelocking() &&
            tables->view->sroutines.records)
        {
          /* We have at least one table in TL here */
          if (!query_tables_last_own)
            query_tables_last_own= thd->lex->query_tables_last;
          sp_cache_routines_and_add_tables_for_view(thd, thd->lex,
                                                    tables->view);
        }
        /* Cleanup hashes because destructo for this LEX is never called */
        hash_free(&tables->view->sroutines);
	continue;
      }

      if (refresh)				// Refresh in progress
      {
	/* close all 'old' tables used by this thread */
	pthread_mutex_lock(&LOCK_open);
	// if query_id is not reset, we will get an error
	// re-opening a temp table
	thd->version=refresh_version;
	TABLE **prev_table= &thd->open_tables;
	bool found=0;
        /*
          QQ: What we should do if we have started building of table list
          for prelocking ??? Probably throw it away ? But before we should
          mark all temporary tables as free? How about locked ?
        */
	for (TABLE_LIST *tmp= *start; tmp; tmp= tmp->next_global)
	{
	  /* Close normal (not temporary) changed tables */
	  if (tmp->table && ! tmp->table->s->tmp_table)
	  {
	    if (tmp->table->s->version != refresh_version ||
		! tmp->table->db_stat)
	    {
	      VOID(hash_delete(&open_cache,(byte*) tmp->table));
	      tmp->table=0;
	      found=1;
	    }
	    else
	    {
	      *prev_table= tmp->table;		// Relink open list
	      prev_table= &tmp->table->next;
	    }
	  }
	}
	*prev_table=0;
	pthread_mutex_unlock(&LOCK_open);
	if (found)
	  VOID(pthread_cond_broadcast(&COND_refresh)); // Signal to refresh
	goto restart;
      }
      result= -1;				// Fatal error
      break;
    }
    else
    {
      /*
        If we are not already in prelocked mode and extended table list is not
        yet built and we have trigger for table being opened then we should
        cache all routines used by its triggers and add their tables to
        prelocking list.
        If we lock table for reading we won't update it so there is no need to
        process its triggers since they never will be activated.
      */
      if (!thd->prelocked_mode && !thd->lex->requires_prelocking() &&
          tables->table->triggers &&
          tables->lock_type >= TL_WRITE_ALLOW_WRITE)
      {
        if (!query_tables_last_own)
            query_tables_last_own= thd->lex->query_tables_last;
        sp_cache_routines_and_add_tables_for_triggers(thd, thd->lex,
                                                      tables->table->triggers);
      }
      free_root(&new_frm_mem, MYF(MY_KEEP_PREALLOC));
    }

    if (tables->lock_type != TL_UNLOCK && ! thd->locked_tables)
      tables->table->reginfo.lock_type=tables->lock_type;
    tables->table->grant= tables->grant;
  }
  thd->proc_info=0;
  free_root(&new_frm_mem, MYF(0));              // Free pre-alloced block

  if (query_tables_last_own)
    thd->lex->mark_as_requiring_prelocking(query_tables_last_own);

  DBUG_RETURN(result);
}


/*
  Check that lock is ok for tables; Call start stmt if ok

  SYNOPSIS
    check_lock_and_start_stmt()
    thd			Thread handle
    table_list		Table to check
    lock_type		Lock used for table

  RETURN VALUES
  0	ok
  1	error
*/

static bool check_lock_and_start_stmt(THD *thd, TABLE *table,
				      thr_lock_type lock_type)
{
  int error;
  DBUG_ENTER("check_lock_and_start_stmt");

  if ((int) lock_type >= (int) TL_WRITE_ALLOW_READ &&
      (int) table->reginfo.lock_type < (int) TL_WRITE_ALLOW_READ)
  {
    my_error(ER_TABLE_NOT_LOCKED_FOR_WRITE, MYF(0),table->alias);
    DBUG_RETURN(1);
  }
  if ((error=table->file->start_stmt(thd)))
  {
    table->file->print_error(error,MYF(0));
    DBUG_RETURN(1);
  }
  DBUG_RETURN(0);
}


/*
  Open and lock one table

  SYNOPSIS
    open_ltable()
    thd			Thread handler
    table_list		Table to open is first table in this list
    lock_type		Lock to use for open

  NOTE
    This function don't do anything like SP/SF/views/triggers analysis done
    in open_tables(). It is intended for opening of only one concrete table.
    And used only in special contexts.

  RETURN VALUES
    table		Opened table
    0			Error
  
    If ok, the following are also set:
      table_list->lock_type 	lock_type
      table_list->table		table
*/

TABLE *open_ltable(THD *thd, TABLE_LIST *table_list, thr_lock_type lock_type)
{
  TABLE *table;
  bool refresh;
  DBUG_ENTER("open_ltable");

  thd->proc_info="Opening table";
  thd->current_tablenr= 0;
  /* open_ltable can be used only for BASIC TABLEs */
  table_list->required_type= FRMTYPE_TABLE;
  while (!(table= open_table(thd, table_list, thd->mem_root, &refresh, 0)) &&
         refresh)
    ;

  if (table)
  {
#if defined( __WIN__) || defined(OS2)
    /* Win32 can't drop a file that is open */
    if (lock_type == TL_WRITE_ALLOW_READ)
    {
      lock_type= TL_WRITE;
    }
#endif /* __WIN__ || OS2 */
    table_list->lock_type= lock_type;
    table_list->table=	   table;
    table->grant= table_list->grant;
    if (thd->locked_tables)
    {
      if (check_lock_and_start_stmt(thd, table, lock_type))
	table= 0;
    }
    else
    {
      DBUG_ASSERT(thd->lock == 0);	// You must lock everything at once
      if ((table->reginfo.lock_type= lock_type) != TL_UNLOCK)
	if (! (thd->lock= mysql_lock_tables(thd, &table_list->table, 1, 0)))
	  table= 0;
    }
  }
  thd->proc_info=0;
  DBUG_RETURN(table);
}


/*
  Open all tables in list and locks them for read without derived
  tables processing.

  SYNOPSIS
    simple_open_n_lock_tables()
    thd		- thread handler
    tables	- list of tables for open&locking

  RETURN
    0  - ok
    -1 - error

  NOTE
    The lock will automaticaly be freed by close_thread_tables()
*/

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))
    DBUG_RETURN(-1);				/* purecov: inspected */
  DBUG_RETURN(0);
}


/*
  Open all tables in list, locks them and process derived tables
  tables processing.

  SYNOPSIS
    open_and_lock_tables()
    thd		- thread handler
    tables	- list of tables for open&locking

  RETURN
    FALSE - ok
    TRUE  - error

  NOTE
    The lock will automaticaly be freed by close_thread_tables()
*/

bool open_and_lock_tables(THD *thd, TABLE_LIST *tables)
{
  uint counter;
  DBUG_ENTER("open_and_lock_tables");
  if (open_tables(thd, &tables, &counter) ||
      lock_tables(thd, tables, counter) ||
      mysql_handle_derived(thd->lex, &mysql_derived_prepare) ||
      (thd->fill_derived_tables() &&
       mysql_handle_derived(thd->lex, &mysql_derived_filling)))
    DBUG_RETURN(TRUE); /* purecov: inspected */
  DBUG_RETURN(0);
}


/*
  Open all tables in list and process derived tables

  SYNOPSIS
    open_normal_and_derived_tables
    thd		- thread handler
    tables	- list of tables for open

  RETURN
    FALSE - ok
    TRUE  - error

  NOTE 
    This is to be used on prepare stage when you don't read any
    data from the tables.
*/

bool open_normal_and_derived_tables(THD *thd, TABLE_LIST *tables)
{
  uint counter;
  DBUG_ENTER("open_normal_and_derived_tables");
  DBUG_ASSERT(!thd->fill_derived_tables());
  if (open_tables(thd, &tables, &counter) ||
      mysql_handle_derived(thd->lex, &mysql_derived_prepare))
    DBUG_RETURN(TRUE); /* purecov: inspected */
  DBUG_RETURN(0);
}


/*
  Mark all real tables in the list as free for reuse.

  SYNOPSIS
    mark_real_tables_as_free_for_reuse()
      thd   - thread context
      table - head of the list of tables

  DESCRIPTION
    Marks all real tables in the list (i.e. not views, derived
    or schema tables) as free for reuse.
*/

static void mark_real_tables_as_free_for_reuse(TABLE_LIST *table)
{
  for (; table; table= table->next_global)
    if (!table->placeholder() && !table->schema_table)
      table->table->query_id= 0;
}


/*
  Lock all tables in list

  SYNOPSIS
    lock_tables()
    thd			Thread handler
    tables		Tables to lock
    count		umber of opened tables

  NOTES
    You can't call lock_tables twice, as this would break the dead-lock-free
    handling thr_lock gives us.  You most always get all needed locks at
    once.

    If query for which we are calling this function marked as requring
    prelocking, this function will do implicit LOCK TABLES and change
    thd::prelocked_mode accordingly.

  RETURN VALUES
   0	ok
   -1	Error
*/

int lock_tables(THD *thd, TABLE_LIST *tables, uint count)
{
  TABLE_LIST *table;

  DBUG_ENTER("lock_tables");
  /*
    We can't meet statement requiring prelocking if we already
    in prelocked mode.
  */
  DBUG_ASSERT(!thd->prelocked_mode || !thd->lex->requires_prelocking());
  /*
    If statement requires prelocking then it has non-empty table list.
    So it is safe to shortcut.
  */
  DBUG_ASSERT(!thd->lex->requires_prelocking() || tables);

  if (!tables)
    DBUG_RETURN(0);

  /*
    We need this extra check for thd->prelocked_mode because we want to avoid
    attempts to lock tables in substatements. Checking for thd->locked_tables
    is not enough in some situations. For example for SP containing
    "drop table t3; create temporary t3 ..; insert into t3 ...;"
    thd->locked_tables may be 0 after drop tables, and without this extra
    check insert will try to lock temporary table t3, that will lead
    to memory leak...
  */
  if (!thd->locked_tables && !thd->prelocked_mode)
  {
    DBUG_ASSERT(thd->lock == 0);	// You must lock everything at once
    TABLE **start,**ptr;

    if (!(ptr=start=(TABLE**) thd->alloc(sizeof(TABLE*)*count)))
      DBUG_RETURN(-1);
    for (table= tables; table; table= table->next_global)
    {
      if (!table->placeholder() && !table->schema_table)
	*(ptr++)= table->table;
    }

    /* We have to emulate LOCK TABLES if we are statement needs prelocking. */
    if (thd->lex->requires_prelocking())
    {
      thd->in_lock_tables=1;
      thd->options|= OPTION_TABLE_LOCK;
    }

    if (! (thd->lock= mysql_lock_tables(thd, start, (uint) (ptr - start), 0)))
    {
      if (thd->lex->requires_prelocking())
      {
        thd->options&= ~(ulong) (OPTION_TABLE_LOCK);
        thd->in_lock_tables=0;
      }
      DBUG_RETURN(-1);
    }
    if (thd->lex->requires_prelocking() &&
        thd->lex->sql_command != SQLCOM_LOCK_TABLES)
    {
      TABLE_LIST *first_not_own= thd->lex->first_not_own_table();
      /*
        We just have done implicit LOCK TABLES, and now we have
        to emulate first open_and_lock_tables() after it.

        Note that "LOCK TABLES" can also be marked as requiring prelocking
        (e.g. if one locks view which uses functions). We should not emulate
        such open_and_lock_tables() in this case. We also should not set
        THD::prelocked_mode or first close_thread_tables() call will do
        "UNLOCK TABLES".
      */
      thd->locked_tables= thd->lock;
      thd->lock= 0;
      thd->in_lock_tables=0;

      for (table= tables; table != first_not_own; table= table->next_global)
      {
        if (!table->placeholder() && !table->schema_table)
        {
          table->table->query_id= thd->query_id;
          if (check_lock_and_start_stmt(thd, table->table, table->lock_type))
          {
            ha_rollback_stmt(thd);
            mysql_unlock_tables(thd, thd->locked_tables);
            thd->locked_tables= 0;
            thd->options&= ~(ulong) (OPTION_TABLE_LOCK);
            DBUG_RETURN(-1);
          }
        }
      }
      /*
        Let us mark all tables which don't belong to the statement itself,
        and was marked as occupied during open_tables() as free for reuse.
      */
      mark_real_tables_as_free_for_reuse(first_not_own);
      thd->prelocked_mode= PRELOCKED;
    }
  }
  else
  {
    TABLE_LIST *first_not_own= thd->lex->first_not_own_table();
    for (table= tables; table != first_not_own; table= table->next_global)
    {
      if (!table->placeholder() && !table->schema_table &&
	  check_lock_and_start_stmt(thd, table->table, table->lock_type))
      {
	ha_rollback_stmt(thd);
	DBUG_RETURN(-1);
      }
    }
    /*
      If we are under explicit LOCK TABLES and our statement requires
      prelocking, we should mark all "additional" tables as free for use
      and enter prelocked mode.
    */
    if (thd->lex->requires_prelocking())
    {
      mark_real_tables_as_free_for_reuse(first_not_own);
      thd->prelocked_mode= PRELOCKED_UNDER_LOCK_TABLES;
    }
  }
  DBUG_RETURN(0);
}


/*
  Open a single table without table caching and don't set it in open_list
  Used by alter_table to open a temporary table and when creating
  a temporary table with CREATE TEMPORARY ...
*/

TABLE *open_temporary_table(THD *thd, const char *path, const char *db,
			    const char *table_name, bool link_in_list)
{
  TABLE *tmp_table;
  TABLE_SHARE *share;
  DBUG_ENTER("open_temporary_table");

  /*
    The extra size in my_malloc() is for table_cache_key
    4 bytes for master thread id if we are in the slave
    1 byte to terminate db
    1 byte to terminate table_name
    total of 6 extra bytes in my_malloc in addition to table/db stuff
  */
  if (!(tmp_table=(TABLE*) my_malloc(sizeof(*tmp_table)+(uint) strlen(db)+
				     (uint) strlen(table_name)+6+4,
				     MYF(MY_WME))))
    DBUG_RETURN(0);				/* purecov: inspected */

  if (openfrm(thd, path, table_name,
	      (uint) (HA_OPEN_KEYFILE | HA_OPEN_RNDFILE | HA_GET_INDEX),
	      READ_KEYINFO | COMPUTE_TYPES | EXTRA_RECORD,
	      ha_open_options,
	      tmp_table))
  {
    my_free((char*) tmp_table,MYF(0));
    DBUG_RETURN(0);
  }

  share= tmp_table->s;
  tmp_table->reginfo.lock_type=TL_WRITE;	 // Simulate locked
  share->tmp_table= (tmp_table->file->has_transactions() ? 
                     TRANSACTIONAL_TMP_TABLE : TMP_TABLE);
  share->table_cache_key= (char*) (tmp_table+1);
  share->db= share->table_cache_key;
  share->key_length= (uint) (strmov(((char*) (share->table_name=
                                              strmov(share->table_cache_key,
                                                     db)+1)),
                                    table_name) -
                             share->table_cache_key) +1;
  int4store(share->table_cache_key + share->key_length, thd->server_id);
  share->key_length+= 4;
  int4store(share->table_cache_key + share->key_length,
	    thd->variables.pseudo_thread_id);
  share->key_length+= 4;

  if (link_in_list)
  {
    tmp_table->next=thd->temporary_tables;
    thd->temporary_tables=tmp_table;
    if (thd->slave_thread)
      slave_open_temp_tables++;
  }
  DBUG_RETURN(tmp_table);
}


bool rm_temporary_table(enum db_type base, char *path)
{
  bool error=0;
  DBUG_ENTER("rm_temporary_table");

  fn_format(path, path,"",reg_ext,4);
  unpack_filename(path,path);
  if (my_delete(path,MYF(0)))
    error=1; /* purecov: inspected */
  *fn_ext(path)='\0';				// remove extension
  handler *file=get_new_handler((TABLE*) 0, base);
  if (file && file->delete_table(path))
  {
    error=1;
    sql_print_warning("Could not remove tmp table: '%s', error: %d",
                      path, my_errno);
  }
  delete file;
  DBUG_RETURN(error);
}


/*****************************************************************************
** find field in list or tables. if field is unqualifed and unique,
** return unique field
******************************************************************************/

/* Special Field pointers for find_field_in_tables returning */
Field *not_found_field= (Field*) 0x1;
Field *view_ref_found= (Field*) 0x2; 

#define WRONG_GRANT (Field*) -1


/*
  Find field in table or view

  SYNOPSIS
    find_field_in_table()
    thd				thread handler
    table_list			table where to find
    name			name of field
    item_name                   name of item if it will be created (VIEW)
    length			length of name
    ref	[in/out]		expression substituted in VIEW should be
				  passed using this reference (return
				  view_ref_found)
                                  (*ref != NULL) only if *ref contains
                                  the item that we need to replace.
    check_grants_table		do check columns grants for table?
    check_grants_view		do check columns grants for view?
    allow_rowid			do allow finding of "_rowid" field?
    cached_field_index_ptr	cached position in field list (used to
				  speedup prepared tables field finding)
    register_tree_change        TRUE if ref is not stack variable and we
                                  need register changes in item tree

  RETURN
    0			field is not found
    view_ref_found	found value in VIEW (real result is in *ref)
    #			pointer to field
*/

Field *
find_field_in_table(THD *thd, TABLE_LIST *table_list,
                    const char *name, const char *item_name,
                    uint length, Item **ref,
                    bool check_grants_table, bool check_grants_view,
                    bool allow_rowid,
                    uint *cached_field_index_ptr,
                    bool register_tree_change)
{
  Field *fld;
  DBUG_ENTER("find_field_in_table");
  DBUG_PRINT("enter", ("table: '%s'  name: '%s'  item name: '%s'  ref 0x%lx",
		       table_list->alias, name, item_name, (ulong) ref));
  if (table_list->field_translation)
  {
    Field_iterator_view field_it;
    field_it.set(table_list);
    DBUG_ASSERT(table_list->schema_table_reformed ||
                (ref != 0 && table_list->view != 0));
    for (; !field_it.end_of_fields(); field_it.next())
    {
      if (!my_strcasecmp(system_charset_info, field_it.name(), name))
      {
        if (table_list->schema_table_reformed)
        {
          /*
            Translation table items are always Item_fields 
            and fixed already('mysql_schema_table' function). 
            So we can return ->field. It is used only for 
            'show & where' commands.
          */
          DBUG_RETURN(((Item_field*) (field_it.item()))->field);
        }
#ifndef NO_EMBEDDED_ACCESS_CHECKS
	if (check_grants_view &&
	    check_grant_column(thd, &table_list->grant,
			       table_list->view_db.str,
			       table_list->view_name.str,
			       name, length))
	  DBUG_RETURN(WRONG_GRANT);
#endif
        Item *item= field_it.create_item(thd);
        if (!item)
        {
          DBUG_RETURN(0);
        }
        /*
          *ref != NULL means that *ref contains the item that we need to
          replace. If the item was aliased by the user, set the alias to
          the replacing item.
         */
        if (*ref && !(*ref)->is_autogenerated_name)
          item->set_name((*ref)->name, (*ref)->name_length,
                         system_charset_info);
        if (register_tree_change)
          thd->change_item_tree(ref, item);
        else
          *ref= item;
	DBUG_RETURN((Field*) view_ref_found);
      }
    }
    DBUG_RETURN(0);
  }
  fld= find_field_in_real_table(thd, table_list->table, name, length,
				check_grants_table, allow_rowid,
				cached_field_index_ptr);
#ifndef NO_EMBEDDED_ACCESS_CHECKS
  /* check for views with temporary table algorithm */
  if (check_grants_view && table_list->view &&
      fld && fld != WRONG_GRANT &&
      check_grant_column(thd, &table_list->grant,
			 table_list->view_db.str,
			 table_list->view_name.str,
			 name, length))
  {
    DBUG_RETURN(WRONG_GRANT);
  }
#endif
  DBUG_RETURN(fld);
}


/*
  Find field in table

  SYNOPSIS
    find_field_in_real_table()
    thd				thread handler
    table_list			table where to find
    name			name of field
    length			length of name
    check_grants		do check columns grants?
    allow_rowid			do allow finding of "_rowid" field?
    cached_field_index_ptr	cached position in field list (used to
				  speedup prepared tables field finding)

  RETURN
    0			field is not found
    #			pointer to field
*/

Field *find_field_in_real_table(THD *thd, TABLE *table,
                                const char *name, uint length,
                                bool check_grants, bool allow_rowid,
                                uint *cached_field_index_ptr)
{
  Field **field_ptr, *field;
  uint cached_field_index= *cached_field_index_ptr;

  /* We assume here that table->field < NO_CACHED_FIELD_INDEX = UINT_MAX */
  if (cached_field_index < table->s->fields &&
      !my_strcasecmp(system_charset_info, 
                     table->field[cached_field_index]->field_name, name))
    field_ptr= table->field + cached_field_index;
  else if (table->s->name_hash.records)
    field_ptr= (Field**) hash_search(&table->s->name_hash, (byte*) name,
                                     length);
  else
  {
    if (!(field_ptr= table->field))
      return (Field *)0;
    for (; *field_ptr; ++field_ptr)
      if (!my_strcasecmp(system_charset_info, (*field_ptr)->field_name, name))
        break;
  }

  if (field_ptr && *field_ptr)
  {
    *cached_field_index_ptr= field_ptr - table->field;
    field= *field_ptr;
  }
  else
  {
    if (!allow_rowid ||
        my_strcasecmp(system_charset_info, name, "_rowid") ||
        !(field=table->rowid_field))
      return (Field*) 0;
  }

  if (thd->set_query_id)
  {
    if (field->query_id != thd->query_id)
    {
      field->query_id=thd->query_id;
      table->used_fields++;
      table->used_keys.intersect(field->part_of_key);
    }
    else
      thd->dupp_field=field;
  }
#ifndef NO_EMBEDDED_ACCESS_CHECKS
  if (check_grants && check_grant_column(thd, &table->grant,
					 table->s->db,
					 table->s->table_name, name, length))
    return WRONG_GRANT;
#endif
  return field;
}


/*
  Find field in table list.

  SYNOPSIS
    find_field_in_tables()
    thd                   Pointer to current thread structure
    item                  Field item that should be found
    tables                Tables to be searched for item
    ref                   If 'item' is resolved to a view field, ref is set to
                          point to the found view field
    report_error          Degree of error reporting:
                          - IGNORE_ERRORS then do not report any error
                          - IGNORE_EXCEPT_NON_UNIQUE report only non-unique
                           fields, suppress all other errors
                          - REPORT_EXCEPT_NON_UNIQUE report all other errors
                            except when non-unique fields were found
                          - REPORT_ALL_ERRORS
    check_privileges      need to check privileges
    register_tree_change  TRUE if ref is not stack variable and we
                            need register changes in item tree

  RETURN VALUES
    0			If error: the found field is not unique, or there are
                        no sufficient access priviliges for the found field,
                        or the field is qualified with non-existing table.
    not_found_field	The function was called with report_error ==
                        (IGNORE_ERRORS || IGNORE_EXCEPT_NON_UNIQUE) and a
			field was not found.
    view_ref_found	View field is found, item passed through ref parameter
    found field         If a item was resolved to some field
*/

Field *
find_field_in_tables(THD *thd, Item_ident *item, TABLE_LIST *tables,
		     Item **ref, find_item_error_report_type report_error,
                     bool check_privileges, bool register_tree_change)
{
  Field *found=0;
  const char *db=item->db_name;
  const char *table_name=item->table_name;
  const char *name=item->field_name;
  uint length=(uint) strlen(name);
  char name_buff[NAME_LEN+1];
  bool allow_rowid;

  if (item->cached_table)
  {
    /*
      This shortcut is used by prepared statements. We assuming that
      TABLE_LIST *tables is not changed during query execution (which
      is true for all queries except RENAME but luckily RENAME doesn't
      use fields...) so we can rely on reusing pointer to its member.
      With this optimization we also miss case when addition of one more
      field makes some prepared query ambiguous and so erroneous, but we
      accept this trade off.
    */
    if (item->cached_table->table && !item->cached_table->view)
    {
      found= find_field_in_real_table(thd, item->cached_table->table,
				      name, length,
				      test(item->cached_table->
					   table->grant.want_privilege) &&
				      check_privileges,
				      1, &(item->cached_field_index));

    }
    else
    {
      TABLE_LIST *table= item->cached_table;
      found= find_field_in_table(thd, table, name, item->name, length,
				       ref,
				       (table->table &&
					test(table->table->grant.
					     want_privilege) &&
					check_privileges),
				       (test(table->grant.want_privilege) &&
					check_privileges),
				       1, &(item->cached_field_index),
                                       register_tree_change);
    }
    if (found)
    {
      if (found == WRONG_GRANT)
	return (Field*) 0;
      {
        SELECT_LEX *current_sel= thd->lex->current_select;
        SELECT_LEX *last_select= item->cached_table->select_lex;
        /*
          If the field was an outer referencee, mark all selects using this
          sub query as dependent of the outer query
        */
        if (current_sel != last_select)
          mark_select_range_as_dependent(thd, last_select, current_sel,
                                         found, *ref, item);
      }
      return found;
    }
  }

  if (db && lower_case_table_names)
  {
    /*
      convert database to lower case for comparison.
      We can't do this in Item_field as this would change the
      'name' of the item which may be used in the select list
    */
    strmake(name_buff, db, sizeof(name_buff)-1);
    my_casedn_str(files_charset_info, name_buff);
    db= name_buff;
  }

  if (table_name && table_name[0])
  {						/* Qualified field */
    bool found_table= 0;
    for (; tables; tables= tables->next_local)
    {
      /* TODO; Ensure that db and tables->db always points to something ! */
      if (!my_strcasecmp(table_alias_charset, tables->alias, table_name) &&
	  (!db || !db[0] || !tables->db ||  !tables->db[0] ||
           !strcmp(db,tables->db)))
      {
	found_table=1;
	Field *find= find_field_in_table(thd, tables, name, item->name,
                                         length, ref,
					 (tables->table &&
					  test(tables->table->grant.
                                               want_privilege) &&
                                          check_privileges),
					 (test(tables->grant.want_privilege) &&
                                          check_privileges),
					 1, &(item->cached_field_index),
                                         register_tree_change);
	if (find)
	{
	  item->cached_table= tables;
	  if (!tables->cacheable_table)
	    item->cached_table= 0;
	  if (find == WRONG_GRANT)
	    return (Field*) 0;
	  if (db || !thd->where)
	    return find;
	  if (found)
	  {
            if (report_error == REPORT_ALL_ERRORS ||
                report_error == IGNORE_EXCEPT_NON_UNIQUE)
              my_error(ER_NON_UNIQ_ERROR, MYF(0),
                       item->full_name(),thd->where);
	    return (Field*) 0;
	  }
	  found=find;
	}
      }
    }
    if (found)
      return found;
    if (!found_table && (report_error == REPORT_ALL_ERRORS ||
                         report_error == REPORT_EXCEPT_NON_UNIQUE))
    {
      char buff[NAME_LEN*2+1];
      if (db && db[0])
      {
	strxnmov(buff,sizeof(buff)-1,db,".",table_name,NullS);
	table_name=buff;
      }
      my_error(ER_UNKNOWN_TABLE, MYF(0), table_name, thd->where);
    }
    else
      if (report_error == REPORT_ALL_ERRORS ||
          report_error == REPORT_EXCEPT_NON_UNIQUE)
	my_error(ER_BAD_FIELD_ERROR, MYF(0), item->full_name(),thd->where);
      else
	return (Field*) not_found_field;
    return (Field*) 0;
  }
  allow_rowid= tables && !tables->next_local;	// Only one table
  for (; tables ; tables= tables->next_local)
  {
    Field *field;
    if (!tables->table && !tables->ancestor)
    {
      if (report_error == REPORT_ALL_ERRORS ||
          report_error == REPORT_EXCEPT_NON_UNIQUE)
	my_error(ER_BAD_FIELD_ERROR, MYF(0), item->full_name(),thd->where);
      return (Field*) not_found_field;
    }

    field= find_field_in_table(thd, tables, name, item->name,
                               length, ref,
                               (tables->table &&
                                test(tables->table->grant.
                                     want_privilege) &&
                                check_privileges),
                               (test(tables->grant.want_privilege) &&
                                check_privileges),
                               allow_rowid,
                               &(item->cached_field_index),
                               register_tree_change);
    if (field)
    {
      if (field == WRONG_GRANT)
	return (Field*) 0;
      item->cached_table= (!tables->cacheable_table || found) ? 0 : tables;
      if (found)
      {
	if (!thd->where)			// Returns first found
	  break;
        if (report_error == REPORT_ALL_ERRORS ||
            report_error == IGNORE_EXCEPT_NON_UNIQUE)
          my_error(ER_NON_UNIQ_ERROR, MYF(0), name, thd->where);
	return (Field*) 0;
      }
      found= field;
    }
  }
  if (found)
    return found;
  if (report_error == REPORT_ALL_ERRORS ||
      report_error == REPORT_EXCEPT_NON_UNIQUE)
    my_error(ER_BAD_FIELD_ERROR, MYF(0), item->full_name(), thd->where);
  else
    return (Field*) not_found_field;
  return (Field*) 0;
}


/*
  Find Item in list of items (find_field_in_tables analog)

  TODO
    is it better return only counter?

  SYNOPSIS
    find_item_in_list()
    find			Item to find
    items			List of items
    counter			To return number of found item
    report_error
      REPORT_ALL_ERRORS		report errors, return 0 if error
      REPORT_EXCEPT_NOT_FOUND	Do not report 'not found' error and
				return not_found_item, report other errors,
				return 0
      IGNORE_ERRORS		Do not report errors, return 0 if error
    unaliased                   Set to true if item is field which was found
                                by original field name and not by its alias
                                in item list. Set to false otherwise.

  RETURN VALUES
    0			Item is not found or item is not unique,
			error message is reported
    not_found_item	Function was called with
			report_error == REPORT_EXCEPT_NOT_FOUND and
			item was not found. No error message was reported
                        found field
*/

/* Special Item pointer to serve as a return value from find_item_in_list(). */
Item **not_found_item= (Item**) 0x1;


Item **
find_item_in_list(Item *find, List<Item> &items, uint *counter,
                  find_item_error_report_type report_error, bool *unaliased)
{
  List_iterator<Item> li(items);
  Item **found=0, **found_unaliased= 0, *item;
  const char *db_name=0;
  const char *field_name=0;
  const char *table_name=0;
  bool found_unaliased_non_uniq= 0;
  uint unaliased_counter;

  LINT_INIT(unaliased_counter);                 // Dependent on found_unaliased

  *unaliased= FALSE;

  if (find->type() == Item::FIELD_ITEM	|| find->type() == Item::REF_ITEM)
  {
    field_name= ((Item_ident*) find)->field_name;
    table_name= ((Item_ident*) find)->table_name;
    db_name=    ((Item_ident*) find)->db_name;
  }

  for (uint i= 0; (item=li++); i++)
  {
    if (field_name && item->type() == Item::FIELD_ITEM)
    {
      Item_field *item_field= (Item_field*) item;

      /*
	In case of group_concat() with ORDER BY condition in the QUERY
	item_field can be field of temporary table without item name 
	(if this field created from expression argument of group_concat()),
	=> we have to check presence of name before compare
      */ 
      if (!item_field->name)
        continue;

      if (table_name)
      {
        /*
          If table name is specified we should find field 'field_name' in
          table 'table_name'. According to SQL-standard we should ignore
          aliases in this case.

          Since we should NOT prefer fields from the select list over
          other fields from the tables participating in this select in
          case of ambiguity we have to do extra check outside this function.

          We use strcmp for table names and database names as these may be
          case sensitive. In cases where they are not case sensitive, they
          are always in lower case.

	  item_field->field_name and item_field->table_name can be 0x0 if
	  item is not fix_field()'ed yet.
        */
        if (item_field->field_name && item_field->table_name &&
	    !my_strcasecmp(system_charset_info, item_field->field_name,
                           field_name) &&
            !strcmp(item_field->table_name, table_name) &&
            (!db_name || (item_field->db_name &&
                          !strcmp(item_field->db_name, db_name))))
        {
          if (found_unaliased)
          {
            if ((*found_unaliased)->eq(item, 0))
              continue;
            /*
              Two matching fields in select list.
              We already can bail out because we are searching through
              unaliased names only and will have duplicate error anyway.
            */
            if (report_error != IGNORE_ERRORS)
              my_error(ER_NON_UNIQ_ERROR, MYF(0),
                       find->full_name(), current_thd->where);
            return (Item**) 0;
          }
          found_unaliased= li.ref();
          unaliased_counter= i;
          if (db_name)
            break;                              // Perfect match
        }
      }
      else if (!my_strcasecmp(system_charset_info, item_field->name,
                              field_name))
      {
        /*
          If table name was not given we should scan through aliases
          (or non-aliased fields) first. We are also checking unaliased
          name of the field in then next else-if, to be able to find
          instantly field (hidden by alias) if no suitable alias (or
          non-aliased field) was found.
        */
        if (found)
        {
          if ((*found)->eq(item, 0))
            continue;                           // Same field twice
          if (report_error != IGNORE_ERRORS)
            my_error(ER_NON_UNIQ_ERROR, MYF(0),
                     find->full_name(), current_thd->where);
          return (Item**) 0;
        }
        found= li.ref();
        *counter= i;
      }
      else if (!my_strcasecmp(system_charset_info, item_field->field_name,
                              field_name))
      {
        /*
          We will use un-aliased field or react on such ambiguities only if
          we won't be able to find aliased field.
          Again if we have ambiguity with field outside of select list
          we should prefer fields from select list.
        */
        if (found_unaliased)
        {
          if ((*found_unaliased)->eq(item, 0))
            continue;                           // Same field twice
          found_unaliased_non_uniq= 1;
        }
        else
        {
          found_unaliased= li.ref();
          unaliased_counter= i;
        }
      }
    }
    else if (!table_name && (item->eq(find,0) ||
			     find->name && item->name &&
			     !my_strcasecmp(system_charset_info, 
					    item->name,find->name)))
    {
      found= li.ref();
      *counter= i;
      break;
    }
  }
  if (!found)
  {
    if (found_unaliased_non_uniq)
    {
      if (report_error != IGNORE_ERRORS)
        my_error(ER_NON_UNIQ_ERROR, MYF(0),
                 find->full_name(), current_thd->where);
      return (Item **) 0;
    }
    if (found_unaliased)
    {
      found= found_unaliased;
      *counter= unaliased_counter;
      *unaliased= TRUE;
    }
  }
  if (found)
    return found;
  if (report_error != REPORT_EXCEPT_NOT_FOUND)
  {
    if (report_error == REPORT_ALL_ERRORS)
      my_error(ER_BAD_FIELD_ERROR, MYF(0),
               find->full_name(), current_thd->where);
    return (Item **) 0;
  }
  else
    return (Item **) not_found_item;
}

/****************************************************************************
** Expand all '*' in given fields
****************************************************************************/

int setup_wild(THD *thd, TABLE_LIST *tables, List<Item> &fields,
	       List<Item> *sum_func_list,
	       uint wild_num)
{
  if (!wild_num)
    return(0);

  Item *item;
  List_iterator<Item> it(fields);
  Query_arena *arena, backup;
  DBUG_ENTER("setup_wild");

  /*
    Don't use arena if we are not in prepared statements or stored procedures
    For PS/SP we have to use arena to remember the changes
  */
  arena= thd->change_arena_if_needed(&backup);

  while (wild_num && (item= it++))
  {
    if (item->type() == Item::FIELD_ITEM &&
        ((Item_field*) item)->field_name &&
	((Item_field*) item)->field_name[0] == '*' &&
	!((Item_field*) item)->field)
    {
      uint elem= fields.elements;
      bool any_privileges= ((Item_field *) item)->any_privileges;
      Item_subselect *subsel= thd->lex->current_select->master_unit()->item;
      if (subsel &&
          subsel->substype() == Item_subselect::EXISTS_SUBS)
      {
        /*
          It is EXISTS(SELECT * ...) and we can replace * by any constant.

          Item_int do not need fix_fields() because it is basic constant.
        */
        it.replace(new Item_int("Not_used", (longlong) 1, 21));
      }
      else if (insert_fields(thd, ((Item_field*) item)->context,
                             ((Item_field*) item)->db_name,
                             ((Item_field*) item)->table_name, &it,
                             any_privileges))
      {
	if (arena)
	  thd->restore_backup_item_arena(arena, &backup);
	DBUG_RETURN(-1);
      }
      if (sum_func_list)
      {
	/*
	  sum_func_list is a list that has the fields list as a tail.
	  Because of this we have to update the element count also for this
	  list after expanding the '*' entry.
	*/
	sum_func_list->elements+= fields.elements - elem;
      }
      wild_num--;
    }
  }
  if (arena)
  {
    /* make * substituting permanent */
    SELECT_LEX *select_lex= thd->lex->current_select;
    select_lex->with_wild= 0;
    select_lex->item_list= fields;

    thd->restore_backup_item_arena(arena, &backup);
  }
  DBUG_RETURN(0);
}

/****************************************************************************
** Check that all given fields exists and fill struct with current data
****************************************************************************/

bool setup_fields(THD *thd, Item **ref_pointer_array,
                  List<Item> &fields, bool set_query_id,
                  List<Item> *sum_func_list, bool allow_sum_func)
{
  reg2 Item *item;
  List_iterator<Item> it(fields);
  DBUG_ENTER("setup_fields");

  thd->set_query_id=set_query_id;
  thd->allow_sum_func= allow_sum_func;
  thd->where="field list";

  /*
    To prevent fail on forward lookup we fill it with zerows,
    then if we got pointer on zero after find_item_in_list we will know
    that it is forward lookup.

    There is other way to solve problem: fill array with pointers to list,
    but it will be slower.

    TODO: remove it when (if) we made one list for allfields and
    ref_pointer_array
  */
  if (ref_pointer_array)
    bzero(ref_pointer_array, sizeof(Item *) * fields.elements);

  Item **ref= ref_pointer_array;
  while ((item= it++))
  {
    if (!item->fixed && item->fix_fields(thd, it.ref()) ||
	(item= *(it.ref()))->check_cols(1))
    {
      DBUG_RETURN(TRUE); /* purecov: inspected */
    }
    if (ref)
      *(ref++)= item;
    if (item->with_sum_func && item->type() != Item::SUM_FUNC_ITEM &&
	sum_func_list)
      item->split_sum_func(thd, ref_pointer_array, *sum_func_list);
    thd->used_tables|=item->used_tables();
  }
  DBUG_RETURN(test(thd->net.report_error));
}


/*
  make list of leaves of join table tree

  SYNOPSIS
    make_leaves_list()
    list    pointer to pointer on list first element
    tables  table list

  RETURN pointer on pointer to next_leaf of last element
*/

TABLE_LIST **make_leaves_list(TABLE_LIST **list, TABLE_LIST *tables)
{
  for (TABLE_LIST *table= tables; table; table= table->next_local)
  {
    if (table->view && table->effective_algorithm == VIEW_ALGORITHM_MERGE)
    {
      list= make_leaves_list(list, table->ancestor);
    }
    else
    {
      *list= table;
      list= &table->next_leaf;
    }
  }
  return list;
}

/*
  prepare tables

  SYNOPSIS
    setup_tables()
    thd		  Thread handler
    context       name resolution contest to setup table list there
    tables	  Table list
    conds	  Condition of current SELECT (can be changed by VIEW)
    leaves        List of join table leaves list
    refresh       It is onle refresh for subquery
    select_insert It is SELECT ... INSERT command

  NOTE
    Check also that the 'used keys' and 'ignored keys' exists and set up the
    table structure accordingly
    Create leaf tables list

    This has to be called for all tables that are used by items, as otherwise
    table->map is not set and all Item_field will be regarded as const items.

  RETURN
    FALSE ok;  In this case *map will includes the choosed index
    TRUE  error
*/

bool setup_tables(THD *thd, Name_resolution_context *context,
                  TABLE_LIST *tables, Item **conds,
                  TABLE_LIST **leaves, bool select_insert)
{
  uint tablenr= 0;
  DBUG_ENTER("setup_tables");

  context->table_list= tables;

  /*
    this is used for INSERT ... SELECT.
    For select we setup tables except first (and its underlying tables)
  */
  TABLE_LIST *first_select_table= (select_insert ?
                                   tables->next_local:
                                   0);
  if (!(*leaves))
    make_leaves_list(leaves, tables);

  TABLE_LIST *table_list;
  for (table_list= *leaves;
       table_list;
       table_list= table_list->next_leaf, tablenr++)
  {
    TABLE *table= table_list->table;
    if (first_select_table &&
        (table_list->belong_to_view ?
         table_list->belong_to_view :
         table_list) == first_select_table)
    {
      /* new counting for SELECT of INSERT ... SELECT command */
      first_select_table= 0;
      tablenr= 0;
    }
    setup_table_map(table, table_list, tablenr);
    table->used_keys= table->s->keys_for_keyread;
    if (table_list->use_index)
    {
      key_map map;
      get_key_map_from_key_list(&map, table, table_list->use_index);
      if (map.is_set_all())
	DBUG_RETURN(1);
      table->keys_in_use_for_query=map;
    }
    if (table_list->ignore_index)
    {
      key_map map;
      get_key_map_from_key_list(&map, table, table_list->ignore_index);
      if (map.is_set_all())
	DBUG_RETURN(1);
      table->keys_in_use_for_query.subtract(map);
    }
    table->used_keys.intersect(table->keys_in_use_for_query);
  }
  if (tablenr > MAX_TABLES)
  {
    my_error(ER_TOO_MANY_TABLES,MYF(0),MAX_TABLES);
    DBUG_RETURN(1);
  }
  for (table_list= tables;
       table_list;
       table_list= table_list->next_local)
  {
    if (table_list->ancestor)
    {
      DBUG_ASSERT(table_list->view);
      Query_arena *arena= thd->current_arena, backup;
      bool res;
      if (arena->is_conventional())
        arena= 0;                                   // For easier test
      else
        thd->set_n_backup_item_arena(arena, &backup);
      res= table_list->setup_ancestor(thd);
      if (arena)
        thd->restore_backup_item_arena(arena, &backup);
      if (res)
        DBUG_RETURN(1);
    }
  }
  DBUG_RETURN(0);
}


/*
   Create a key_map from a list of index names

   SYNOPSIS
     get_key_map_from_key_list()
     map		key_map to fill in
     table		Table
     index_list		List of index names

   RETURN
     0	ok;  In this case *map will includes the choosed index
     1	error
*/

bool get_key_map_from_key_list(key_map *map, TABLE *table,
                               List<String> *index_list)
{
  List_iterator_fast<String> it(*index_list);
  String *name;
  uint pos;

  map->clear_all();
  while ((name=it++))
  {
    if (table->s->keynames.type_names == 0 ||
        (pos= find_type(&table->s->keynames, name->ptr(),
                        name->length(), 1)) <=
        0)
    {
      my_error(ER_KEY_COLUMN_DOES_NOT_EXITS, MYF(0), name->c_ptr(),
	       table->s->table_name);
      map->set_all();
      return 1;
    }
    map->set_bit(pos-1);
  }
  return 0;
}


/*
  Drops in all fields instead of current '*' field

  SYNOPSIS
    insert_fields()
    thd			Thread handler
    context             Context for name resolution
    db_name		Database name in case of 'database_name.table_name.*'
    table_name		Table name in case of 'table_name.*'
    it			Pointer to '*'
    any_privileges	0 If we should ensure that we have SELECT privileges
		          for all columns
                        1 If any privilege is ok
  RETURN
    0	ok
        'it' is updated to point at last inserted
    1	error.  Error message is generated but not sent to client
*/

bool
insert_fields(THD *thd, Name_resolution_context *context, const char *db_name,
	      const char *table_name, List_iterator<Item> *it,
              bool any_privileges)
{
  /* allocate variables on stack to avoid pool alloaction */
  Field_iterator_table table_iter;
  Field_iterator_view view_iter;
  uint found;
  char name_buff[NAME_LEN+1];
  DBUG_ENTER("insert_fields");

  if (db_name && lower_case_table_names)
  {
    /*
      convert database to lower case for comparison
      We can't do this in Item_field as this would change the
      'name' of the item which may be used in the select list
    */
    strmake(name_buff, db_name, sizeof(name_buff)-1);
    my_casedn_str(files_charset_info, name_buff);
    db_name= name_buff;
  }

  found= 0;
  for (TABLE_LIST *tables= context->table_list;
       tables;
       tables= tables->next_local)
  {
    Field_iterator *iterator;
    TABLE_LIST *natural_join_table;
    Field *field;
    TABLE_LIST *embedded;
    TABLE_LIST *last;
    TABLE_LIST *embedding;
    TABLE *table= tables->table;

    if (!table_name || (!my_strcasecmp(table_alias_charset, table_name,
				       tables->alias) &&
			(!db_name || !strcmp(tables->db,db_name))))
    {
      bool view;
#ifndef NO_EMBEDDED_ACCESS_CHECKS
      /* Ensure that we have access right to all columns */
      if (!((table && (table->grant.privilege & SELECT_ACL) ||
	     tables->view && (tables->grant.privilege & SELECT_ACL))) &&
	  !any_privileges)
      {
        if (tables->view)
        {
          view_iter.set(tables);
          if (check_grant_all_columns(thd, SELECT_ACL, &tables->grant,
                                      tables->view_db.str,
                                      tables->view_name.str,
                                      &view_iter))
            goto err;
        }
        else if (!tables->schema_table)
        {
	  DBUG_ASSERT(table != 0);
          table_iter.set(tables);
          if (check_grant_all_columns(thd, SELECT_ACL, &table->grant,
                                      table->s->db,
                                      table->s->table_name,
                                      &table_iter))
            goto err;
        }
      }
#endif
      natural_join_table= 0;
      last= embedded= tables;

      while ((embedding= embedded->embedding) &&
              embedding->join_list->elements != 1)
      {
        TABLE_LIST *next;
        List_iterator_fast<TABLE_LIST> it(embedding->nested_join->join_list);
        last= it++;
        while ((next= it++))
          last= next;
        if (last != tables)
          break;
        embedded= embedding;
      }

      if (tables == last &&
          !embedded->outer_join &&
          embedded->natural_join &&
          !embedded->natural_join->outer_join)
      {
        embedding= embedded->natural_join;
        while (embedding->nested_join)
          embedding= embedding->nested_join->join_list.head();
        natural_join_table= embedding;
      }
      if (tables->field_translation)
      {
        iterator= &view_iter;
	view= 1;
      }
      else
      {
        iterator= &table_iter;
	view= 0;
      }
      iterator->set(tables);

      /* for view used tables will be collected in following loop */
      if (table)
	thd->used_tables|= table->map;

      for (; !iterator->end_of_fields(); iterator->next())
      {
        Item *not_used_item;
        uint not_used_field_index= NO_CACHED_FIELD_INDEX;
        const char *field_name= iterator->name();
        /* Skip duplicate field names if NATURAL JOIN is used */
        if (!natural_join_table ||
            !find_field_in_table(thd, natural_join_table, field_name,
                                 field_name,
                                 strlen(field_name), &not_used_item, 0, 0, 0,
                                 &not_used_field_index, TRUE))
        {
          Item *item= iterator->create_item(thd);
          if (!item)
            goto err;
          thd->used_tables|= item->used_tables();
          if (!found++)
            (void) it->replace(item);		// Replace '*'
          else
            it->after(item);
#ifndef NO_EMBEDDED_ACCESS_CHECKS
          if (any_privileges)
          {
            /*
              In time of view creation MEGRGE algorithm for underlying
              VIEWs can't be used => it should be Item_field
            */
            DBUG_ASSERT(item->type() == Item::FIELD_ITEM);
            Item_field *fld= (Item_field*)item;
            char *db, *tab;
            if (tables->view)
            {
              db= tables->view_db.str;
              tab= tables->view_name.str;
            }
            else
            {
              db= tables->db;
              tab= tables->table_name;
            }
            if (!tables->schema_table && 
                !(fld->have_privileges= (get_column_grant(thd,
                                                          &table->grant,
                                                          db,
                                                          tab,
                                                          fld->field_name) &
                                         VIEW_ANY_ACL)))
            {
              my_error(ER_COLUMNACCESS_DENIED_ERROR, MYF(0),
                       "ANY",
                       thd->priv_user,
                       thd->host_or_ip,
                       fld->field_name,
                       tab);
              goto err;
            }
          }
#endif
        }
        if ((field= iterator->field()))
        {
          /*
            Mark if field used before in this select.
            Used by 'insert' to verify if a field name is used twice
          */
          if (field->query_id == thd->query_id)
            thd->dupp_field=field;
          field->query_id=thd->query_id;
          table->used_keys.intersect(field->part_of_key);
        }
        else
        {
          Item *item= ((Field_iterator_view *) iterator)->item();
          item->walk(&Item::reset_query_id_processor,
                     (byte *)(&thd->query_id));
        }
      }
      /*
	All fields are used in case if usual tables (in case of view used
	fields marked in setup_tables during fix_fields of view columns
      */
      if (table)
	table->used_fields= table->s->fields;
    }
  }
  if (found)
    DBUG_RETURN(0);

  if (!table_name)
    my_message(ER_NO_TABLES_USED, ER(ER_NO_TABLES_USED), MYF(0));
  else
    my_error(ER_BAD_TABLE_ERROR, MYF(0), table_name);
err:
  DBUG_RETURN(1);
}


/*
  Fix all conditions and outer join expressions

  SYNOPSIS
    setup_conds()
    thd     thread handler
    leaves  list of leaves of join table tree
*/

int setup_conds(THD *thd, TABLE_LIST *tables, TABLE_LIST *leaves,
                COND **conds)
{
  SELECT_LEX *select_lex= thd->lex->current_select;
  Query_arena *arena= thd->current_arena, backup;
  TABLE_LIST *table= NULL;	// For HP compilers
  /*
    it_is_update set to TRUE when tables of primary SELECT_LEX (SELECT_LEX
    which belong to LEX, i.e. most up SELECT) will be updated by
    INSERT/UPDATE/LOAD
    NOTE: using this condition helps to prevent call of prepare_check_option()
    from subquery of VIEW, because tables of subquery belongs to VIEW
    (see condition before prepare_check_option() call)
  */
  bool it_is_update= (select_lex == &thd->lex->select_lex) &&
    thd->lex->which_check_option_applicable();
  DBUG_ENTER("setup_conds");

  if (select_lex->conds_processed_with_permanent_arena ||
      arena->is_conventional())
    arena= 0;                                   // For easier test

  thd->set_query_id=1;

  for (table= tables; table; table= table->next_local)
  {
    if (table->prepare_where(thd, conds, FALSE))
      goto err_no_arena;
  }

  select_lex->cond_count= 0;
  if (*conds)
  {
    thd->where="where clause";
    if (!(*conds)->fixed && (*conds)->fix_fields(thd, conds) ||
	(*conds)->check_cols(1))
      goto err_no_arena;
  }

  /* Check if we are using outer joins */
  for (table= leaves; table; table= table->next_leaf)
  {
    TABLE_LIST *embedded;
    TABLE_LIST *embedding= table;
    do
    {
      embedded= embedding;
      if (embedded->on_expr)
      {
        /* Make a join an a expression */
        thd->where="on clause";
        if (!embedded->on_expr->fixed &&
            embedded->on_expr->fix_fields(thd, &embedded->on_expr) ||
	    embedded->on_expr->check_cols(1))
	  goto err_no_arena;
        select_lex->cond_count++;
      }

      if (embedded->natural_join)
      {
        /* Make a join of all fields wich have the same name */
        TABLE_LIST *tab1= embedded;
        TABLE_LIST *tab2= embedded->natural_join;
        if (!(embedded->outer_join & JOIN_TYPE_RIGHT))
        {
          while (tab1->nested_join)
          {
            TABLE_LIST *next;
            List_iterator_fast<TABLE_LIST> it(tab1->nested_join->join_list);
            tab1= it++;
            while ((next= it++))
              tab1= next;
          }
        }
        else
        {
          while (tab1->nested_join)
            tab1= tab1->nested_join->join_list.head();
        }
        if (embedded->outer_join & JOIN_TYPE_RIGHT)
        {
          while (tab2->nested_join)
          {
            TABLE_LIST *next;
            List_iterator_fast<TABLE_LIST> it(tab2->nested_join->join_list);
            tab2= it++;
            while ((next= it++))
              tab2= next;
          }
        }
        else
        {
          while (tab2->nested_join)
            tab2= tab2->nested_join->join_list.head();
        }

        if (arena)
	  arena= thd->change_arena_if_needed(&backup);

        TABLE *t1=tab1->table;
        TABLE *t2=tab2->table;
        Field_iterator_table table_iter;
        Field_iterator_view view_iter;
        Field_iterator *iterator;
        Field *t1_field, *t2_field;
        Item *item_t2= 0;
        Item_cond_and *cond_and= new Item_cond_and();

        if (!cond_and)				// If not out of memory
	  goto err_no_arena;
        cond_and->top_level_item();

        if (table->field_translation)
        {
          iterator= &view_iter;
          view_iter.set(tab1);
        }
        else
        {
          iterator= &table_iter;
          table_iter.set(tab1);
        }

        for (; !iterator->end_of_fields(); iterator->next())
        {
          const char *t1_field_name= iterator->name();
          uint not_used_field_index= NO_CACHED_FIELD_INDEX;

          if ((t2_field= find_field_in_table(thd, tab2, t1_field_name,
                                             t1_field_name,
                                             strlen(t1_field_name), &item_t2,
                                             0, 0, 0,
                                             &not_used_field_index,
                                             FALSE)))
          {
            if (t2_field != view_ref_found)
            {
              if (!(item_t2= new Item_field(thd, &select_lex->context,
                                            t2_field)))
                goto err;
              /* Mark field used for table cache */
              t2_field->query_id= thd->query_id;
              t2->used_keys.intersect(t2_field->part_of_key);
            }
            if ((t1_field= iterator->field()))
            {
              /* Mark field used for table cache */
              t1_field->query_id= thd->query_id;
              t1->used_keys.intersect(t1_field->part_of_key);
            }
            Item_func_eq *tmp= new Item_func_eq(iterator->create_item(thd),
                                                item_t2);
            if (!tmp)
              goto err;
            cond_and->list.push_back(tmp);
          }
        }
        select_lex->cond_count+= cond_and->list.elements;

        // to prevent natural join processing during PS re-execution
        embedding->natural_join= 0;

        if (cond_and->list.elements)
        {
          COND *on_expr= cond_and;
          if (!on_expr->fixed)
            on_expr->fix_fields(thd, &on_expr);
          if (!embedded->outer_join)			// Not left join
          {
            *conds= and_conds(*conds, cond_and);
            // fix_fields() should be made with temporary memory pool
            if (arena)
              thd->restore_backup_item_arena(arena, &backup);
            if (*conds && !(*conds)->fixed)
            {
              if ((*conds)->fix_fields(thd, conds))
                goto err_no_arena;
            }
          }
          else
          {
            embedded->on_expr= and_conds(embedded->on_expr, cond_and);
            // fix_fields() should be made with temporary memory pool
            if (arena)
              thd->restore_backup_item_arena(arena, &backup);
            if (embedded->on_expr && !embedded->on_expr->fixed)
            {
              if (embedded->on_expr->fix_fields(thd, &embedded->on_expr))
                goto err_no_arena;
            }
          }
        }
        else if (arena)
	  thd->restore_backup_item_arena(arena, &backup);
      }
      embedding= embedded->embedding;
    }
    while (embedding &&
           embedding->nested_join->join_list.head() == embedded);

    /* process CHECK OPTION */
    if (it_is_update)
    {
      TABLE_LIST *view= table->belong_to_view;
      if (!view)
        view= table;
      if (view->effective_with_check)
      {
        if (view->prepare_check_option(thd))
          goto err_no_arena;
        thd->change_item_tree(&table->check_option, view->check_option);
      }
    }
  }

  if (!thd->current_arena->is_conventional())
  {
    /*
      We are in prepared statement preparation code => we should store
      WHERE clause changing for next executions.

      We do this ON -> WHERE transformation only once per PS/SP statement.
    */
    select_lex->where= *conds;
    select_lex->conds_processed_with_permanent_arena= 1;
  }
  DBUG_RETURN(test(thd->net.report_error));

err:
  if (arena)
    thd->restore_backup_item_arena(arena, &backup);
err_no_arena:
  DBUG_RETURN(1);
}


/******************************************************************************
** Fill a record with data (for INSERT or UPDATE)
** Returns : 1 if some field has wrong type
******************************************************************************/


/*
  Fill fields with given items.

  SYNOPSIS
    fill_record()
    thd           thread handler
    fields        Item_fields list to be filled
    values        values to fill with
    ignore_errors TRUE if we should ignore errors

  RETURN
    FALSE   OK
    TRUE    error occured
*/

static bool
fill_record(THD * thd, List<Item> &fields, List<Item> &values,
            bool ignore_errors)
{
  List_iterator_fast<Item> f(fields),v(values);
  Item *value;
  Item_field *field;
  DBUG_ENTER("fill_record");

  while ((field=(Item_field*) f++))
  {
    value=v++;
    Field *rfield= field->field;
    TABLE *table= rfield->table;
    if (rfield == table->next_number_field)
      table->auto_increment_field_not_null= TRUE;
    if ((value->save_in_field(rfield, 0) < 0) && !ignore_errors)
    {
      my_message(ER_UNKNOWN_ERROR, ER(ER_UNKNOWN_ERROR), MYF(0));
      DBUG_RETURN(TRUE);
    }
  }
  DBUG_RETURN(thd->net.report_error);
}


/*
  Fill fields in list with values from the list of items and invoke
  before triggers.

  SYNOPSIS
    fill_record_n_invoke_before_triggers()
      thd           thread context
      fields        Item_fields list to be filled
      values        values to fill with
      ignore_errors TRUE if we should ignore errors
      triggers      object holding list of triggers to be invoked
      event         event type for triggers to be invoked

  NOTE
    This function assumes that fields which values will be set and triggers
    to be invoked belong to the same table, and that TABLE::record[0] and
    record[1] buffers correspond to new and old versions of row respectively.

  RETURN
    FALSE   OK
    TRUE    error occured
*/

bool
fill_record_n_invoke_before_triggers(THD *thd, List<Item> &fields,
                                     List<Item> &values, bool ignore_errors,
                                     Table_triggers_list *triggers,
                                     enum trg_event_type event)
{
  return (fill_record(thd, fields, values, ignore_errors) ||
          triggers && triggers->process_triggers(thd, event,
                                                 TRG_ACTION_BEFORE, TRUE));
}


/*
  Fill field buffer with values from Field list

  SYNOPSIS
    fill_record()
    thd           thread handler
    ptr           pointer on pointer to record
    values        list of fields
    ignore_errors TRUE if we should ignore errors

  RETURN
    FALSE   OK
    TRUE    error occured
*/

bool
fill_record(THD *thd, Field **ptr, List<Item> &values, bool ignore_errors)
{
  List_iterator_fast<Item> v(values);
  Item *value;
  DBUG_ENTER("fill_record");

  Field *field;
  while ((field = *ptr++))
  {
    value=v++;
    TABLE *table= field->table;
    if (field == table->next_number_field)
      table->auto_increment_field_not_null= TRUE;
    if (value->save_in_field(field, 0) == -1)
      DBUG_RETURN(TRUE);
  }
  DBUG_RETURN(thd->net.report_error);
}


/*
  Fill fields in array with values from the list of items and invoke
  before triggers.

  SYNOPSIS
    fill_record_n_invoke_before_triggers()
      thd           thread context
      ptr           NULL-ended array of fields to be filled
      values        values to fill with
      ignore_errors TRUE if we should ignore errors
      triggers      object holding list of triggers to be invoked
      event         event type for triggers to be invoked

  NOTE
    This function assumes that fields which values will be set and triggers
    to be invoked belong to the same table, and that TABLE::record[0] and
    record[1] buffers correspond to new and old versions of row respectively.

  RETURN
    FALSE   OK
    TRUE    error occured
*/

bool
fill_record_n_invoke_before_triggers(THD *thd, Field **ptr,
                                     List<Item> &values, bool ignore_errors,
                                     Table_triggers_list *triggers,
                                     enum trg_event_type event)
{
  return (fill_record(thd, ptr, values, ignore_errors) ||
          triggers && triggers->process_triggers(thd, event,
                                                 TRG_ACTION_BEFORE, TRUE));
}


static void mysql_rm_tmp_tables(void)
{
  uint i, idx;
  char	filePath[FN_REFLEN], *tmpdir;
  MY_DIR *dirp;
  FILEINFO *file;
  DBUG_ENTER("mysql_rm_tmp_tables");

  for (i=0; i<=mysql_tmpdir_list.max; i++)
  {
    tmpdir=mysql_tmpdir_list.list[i];
  /* See if the directory exists */
    if (!(dirp = my_dir(tmpdir,MYF(MY_WME | MY_DONT_SORT))))
      continue;

    /* Remove all SQLxxx tables from directory */

  for (idx=0 ; idx < (uint) dirp->number_off_files ; idx++)
  {
    file=dirp->dir_entry+idx;

    /* skiping . and .. */
    if (file->name[0] == '.' && (!file->name[1] ||
       (file->name[1] == '.' &&  !file->name[2])))
      continue;

    if (!bcmp(file->name,tmp_file_prefix,tmp_file_prefix_length))
    {
        sprintf(filePath,"%s%s",tmpdir,file->name);
        VOID(my_delete(filePath,MYF(MY_WME)));
    }
  }
  my_dirend(dirp);
  }
  DBUG_VOID_RETURN;
}



/*****************************************************************************
	unireg support functions
*****************************************************************************/

/*
  Invalidate any cache entries that are for some DB

  SYNOPSIS
    remove_db_from_cache()
    db		Database name. This will be in lower case if
		lower_case_table_name is set

  NOTE:
  We can't use hash_delete when looping hash_elements. We mark them first
  and afterwards delete those marked unused.
*/

void remove_db_from_cache(const char *db)
{
  for (uint idx=0 ; idx < open_cache.records ; idx++)
  {
    TABLE *table=(TABLE*) hash_element(&open_cache,idx);
    if (!strcmp(table->s->db, db))
    {
      table->s->version= 0L;			/* Free when thread is ready */
      if (!table->in_use)
	relink_unused(table);
    }
  }
  while (unused_tables && !unused_tables->s->version)
    VOID(hash_delete(&open_cache,(byte*) unused_tables));
}


/*
** free all unused tables
*/

void flush_tables()
{
  (void) pthread_mutex_lock(&LOCK_open);
  while (unused_tables)
    hash_delete(&open_cache,(byte*) unused_tables);
  (void) pthread_mutex_unlock(&LOCK_open);
}


/*
  Mark all entries with the table as deleted to force an reopen of the table

  The table will be closed (not stored in cache) by the current thread when
  close_thread_tables() is called.

  PREREQUISITES
    Lock on LOCK_open()

  RETURN
    0  This thread now have exclusive access to this table and no other thread
       can access the table until close_thread_tables() is called.
    1  Table is in use by another thread
*/

bool remove_table_from_cache(THD *thd, const char *db, const char *table_name,
                             uint flags)
{
  char key[MAX_DBKEY_LENGTH];
  uint key_length;
  TABLE *table;
  bool result=0, signalled= 0;
  DBUG_ENTER("remove_table_from_cache");


  key_length=(uint) (strmov(strmov(key,db)+1,table_name)-key)+1;
  for (;;)
  {
    result= signalled= 0;

    for (table=(TABLE*) hash_search(&open_cache,(byte*) key,key_length) ;
         table;
         table = (TABLE*) hash_next(&open_cache,(byte*) key,key_length))
    {
      THD *in_use;
      table->s->version=0L;		/* Free when thread is ready */
      if (!(in_use=table->in_use))
      {
        DBUG_PRINT("info",("Table was not in use"));
        relink_unused(table);
      }
      else if (in_use != thd)
      {
        in_use->some_tables_deleted=1;
        if (table->db_stat)
  	  result=1;
        /* Kill delayed insert threads */
        if ((in_use->system_thread & SYSTEM_THREAD_DELAYED_INSERT) &&
            ! in_use->killed)
        {
	  in_use->killed= THD::KILL_CONNECTION;
	  pthread_mutex_lock(&in_use->mysys_var->mutex);
	  if (in_use->mysys_var->current_cond)
	  {
	    pthread_mutex_lock(in_use->mysys_var->current_mutex);
            signalled= 1;
	    pthread_cond_broadcast(in_use->mysys_var->current_cond);
	    pthread_mutex_unlock(in_use->mysys_var->current_mutex);
	  }
	  pthread_mutex_unlock(&in_use->mysys_var->mutex);
        }
        /*
	  Now we must abort all tables locks used by this thread
	  as the thread may be waiting to get a lock for another table
        */
        for (TABLE *thd_table= in_use->open_tables;
	     thd_table ;
	     thd_table= thd_table->next)
        {
	  if (thd_table->db_stat)		// If table is open
	    signalled|= mysql_lock_abort_for_thread(thd, thd_table);
        }
      }
      else
        result= result || (flags & RTFC_OWNED_BY_THD_FLAG);
    }
    while (unused_tables && !unused_tables->s->version)
      VOID(hash_delete(&open_cache,(byte*) unused_tables));
    if (result && (flags & RTFC_WAIT_OTHER_THREAD_FLAG))
    {
      if (!(flags & RTFC_CHECK_KILLED_FLAG) || !thd->killed)
      {
        dropping_tables++;
        if (likely(signalled))
          (void) pthread_cond_wait(&COND_refresh, &LOCK_open);
        else
        {
          struct timespec abstime;
          /*
            It can happen that another thread has opened the
            table but has not yet locked any table at all. Since
            it can be locked waiting for a table that our thread
            has done LOCK TABLE x WRITE on previously, we need to
            ensure that the thread actually hears our signal
            before we go to sleep. Thus we wait for a short time
            and then we retry another loop in the
            remove_table_from_cache routine.
          */
          set_timespec(abstime, 10);
          pthread_cond_timedwait(&COND_refresh, &LOCK_open, &abstime);
        }
        dropping_tables--;
        continue;
      }
    }
    break;
  }
  DBUG_RETURN(result);
}

int setup_ftfuncs(SELECT_LEX *select_lex)
{
  List_iterator<Item_func_match> li(*(select_lex->ftfunc_list)),
                                 lj(*(select_lex->ftfunc_list));
  Item_func_match *ftf, *ftf2;

  while ((ftf=li++))
  {
    if (ftf->fix_index())
      return 1;
    lj.rewind();
    while ((ftf2=lj++) != ftf)
    {
      if (ftf->eq(ftf2,1) && !ftf2->master)
        ftf2->master=ftf;
    }
  }

  return 0;
}


int init_ftfuncs(THD *thd, SELECT_LEX *select_lex, bool no_order)
{
  if (select_lex->ftfunc_list->elements)
  {
    List_iterator<Item_func_match> li(*(select_lex->ftfunc_list));
    Item_func_match *ifm;
    DBUG_PRINT("info",("Performing FULLTEXT search"));
    thd->proc_info="FULLTEXT initialization";

    while ((ifm=li++))
      ifm->init_search(no_order);
  }
  return 0;
}


/*
  open new .frm format table

  SYNOPSIS
    open_new_frm()
    path	  path to .frm
    alias	  alias for table
    db            database
    table_name    name of table
    db_stat	  open flags (for example HA_OPEN_KEYFILE|HA_OPEN_RNDFILE..)
		  can be 0 (example in ha_example_table)
    prgflag	  READ_ALL etc..
    ha_open_flags HA_OPEN_ABORT_IF_LOCKED etc..
    outparam	  result table
    table_desc	  TABLE_LIST descriptor
    mem_root	  temporary MEM_ROOT for parsing
*/

static my_bool
open_new_frm(const char *path, const char *alias,
             const char *db, const char *table_name,
             uint db_stat, uint prgflag,
	     uint ha_open_flags, TABLE *outparam, TABLE_LIST *table_desc,
	     MEM_ROOT *mem_root)
{
  LEX_STRING pathstr;
  File_parser *parser;
  DBUG_ENTER("open_new_frm");

  pathstr.str=    (char*) path;
  pathstr.length= strlen(path);

  if ((parser= sql_parse_prepare(&pathstr, mem_root, 1)))
  {
    if (!strncmp("VIEW", parser->type()->str, parser->type()->length))
    {
      if (table_desc == 0 || table_desc->required_type == FRMTYPE_TABLE)
      {
        my_error(ER_WRONG_OBJECT, MYF(0), db, table_name, "BASE TABLE");
        goto err;
      }
      if (mysql_make_view(parser, table_desc))
        goto err;
    }
    else
    {
      /* only VIEWs are supported now */
      my_error(ER_FRM_UNKNOWN_TYPE, MYF(0), path,  parser->type()->str);
      goto err;
    }
    DBUG_RETURN(0);
  }
 
err:
  bzero(outparam, sizeof(TABLE));	// do not run repair
  DBUG_RETURN(1);
}