~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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/* Scan through all rows */
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#include "heapdef.h"
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/*
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	   Returns one of following values:
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	   0 = Ok.
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	   HA_ERR_RECORD_DELETED = Record is deleted.
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	   HA_ERR_END_OF_FILE = EOF.
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*/
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int heap_scan_init(register HP_INFO *info)
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{
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  DBUG_ENTER("heap_scan_init");
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  info->lastinx= -1;
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  info->current_record= (ulong) ~0L;		/* No current record */
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  info->update=0;
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  info->next_block=0;
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  DBUG_RETURN(0);
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}
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int heap_scan(register HP_INFO *info, uchar *record)
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{
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  HP_SHARE *share=info->s;
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  ulong pos;
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  DBUG_ENTER("heap_scan");
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  pos= ++info->current_record;
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  if (pos < info->next_block)
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  {
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    info->current_ptr+=share->block.recbuffer;
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  }
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  else
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  {
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    info->next_block+=share->block.records_in_block;
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    if (info->next_block >= share->records+share->deleted)
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    {
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      info->next_block= share->records+share->deleted;
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      if (pos >= info->next_block)
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      {
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	info->update= 0;
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	DBUG_RETURN(my_errno= HA_ERR_END_OF_FILE);
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      }
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    }
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    hp_find_record(info, pos);
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  }
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  if (!info->current_ptr[share->reclength])
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  {
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    DBUG_PRINT("warning",("Found deleted record"));
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    info->update= HA_STATE_PREV_FOUND | HA_STATE_NEXT_FOUND;
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    DBUG_RETURN(my_errno=HA_ERR_RECORD_DELETED);
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  }
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  info->update= HA_STATE_PREV_FOUND | HA_STATE_NEXT_FOUND | HA_STATE_AKTIV;
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  memcpy(record,info->current_ptr,(size_t) share->reclength);
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  info->current_hash_ptr=0;			/* Can't use read_next */
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  DBUG_RETURN(0);
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} /* heap_scan */