~drizzle-trunk/drizzle/development

1 by brian
clean slate
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/* Copyright (C) 2000-2002 MySQL AB
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   This program is free software; you can redistribute it and/or modify
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   it under the terms of the GNU General Public License as published by
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   the Free Software Foundation; version 2 of the License.
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   This program is distributed in the hope that it will be useful,
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   but WITHOUT ANY WARRANTY; without even the implied warranty of
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   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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   GNU General Public License for more details.
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   You should have received a copy of the GNU General Public License
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   along with this program; if not, write to the Free Software
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   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
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#include "heapdef.h"
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	/* Read prev record for key */
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int heap_rprev(HP_INFO *info, uchar *record)
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{
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  uchar *pos;
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  HP_SHARE *share=info->s;
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  HP_KEYDEF *keyinfo;
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  if (info->lastinx < 0)
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    return(my_errno=HA_ERR_WRONG_INDEX);
1 by brian
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  keyinfo = share->keydef + info->lastinx;
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  if (keyinfo->algorithm == HA_KEY_ALG_BTREE)
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  {
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    heap_rb_param custom_arg;
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    if (info->last_pos)
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      pos = tree_search_next(&keyinfo->rb_tree, &info->last_pos,
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                             offsetof(TREE_ELEMENT, right),
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                             offsetof(TREE_ELEMENT, left));
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    else
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    {
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      custom_arg.keyseg = keyinfo->seg;
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      custom_arg.key_length = keyinfo->length;
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      custom_arg.search_flag = SEARCH_SAME;
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      pos = tree_search_key(&keyinfo->rb_tree, info->lastkey, info->parents, 
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                           &info->last_pos, info->last_find_flag, &custom_arg);
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    }
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    if (pos)
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    {
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      memcpy(&pos, pos + (*keyinfo->get_key_length)(keyinfo, pos),
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	     sizeof(uchar*));
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      info->current_ptr = pos;
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    }
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    else
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    {
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      my_errno = HA_ERR_KEY_NOT_FOUND;
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    }
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  }
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  else
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  {
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    if (info->current_ptr || (info->update & HA_STATE_NEXT_FOUND))
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    {
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      if ((info->update & HA_STATE_DELETED))
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        pos= hp_search(info, share->keydef + info->lastinx, info->lastkey, 3);
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      else
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        pos= hp_search(info, share->keydef + info->lastinx, info->lastkey, 2);
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    }
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    else
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    {
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      pos=0;					/* Read next after last */
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      my_errno=HA_ERR_KEY_NOT_FOUND;
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    }
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  }
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  if (!pos)
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  {
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    info->update=HA_STATE_PREV_FOUND;		/* For heap_rprev */
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    if (my_errno == HA_ERR_KEY_NOT_FOUND)
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      my_errno=HA_ERR_END_OF_FILE;
51.3.1 by Jay Pipes
Removed all DBUG symbols from heap storage engine
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    return(my_errno);
1 by brian
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  }
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  memcpy(record,pos,(size_t) share->reclength);
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  info->update=HA_STATE_AKTIV | HA_STATE_PREV_FOUND;
51.3.1 by Jay Pipes
Removed all DBUG symbols from heap storage engine
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  return(0);
1 by brian
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}