mi_scan.c

/* Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.

   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; version 2 of the License.

   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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */

/* Read through all rows sequntially */

#include "myisamdef.h"

int mi_scan_init(register MI_INFO *info)
{
  DBUG_ENTER("mi_scan_init");
  info->nextpos=info->s->pack.header_length;    /* Read first record */
  info->lastinx= -1;                            /* Can't forward or backward */
  if (info->opt_flag & WRITE_CACHE_USED && flush_io_cache(&info->rec_cache))
    DBUG_RETURN(my_errno);
  DBUG_RETURN(0);
}

/*
           Read a row based on position.
           If filepos= HA_OFFSET_ERROR then read next row
           Return values
           Returns one of following values:
           0 = Ok.
           HA_ERR_END_OF_FILE = EOF.
*/

int mi_scan(MI_INFO *info, uchar *buf)
{
  int result;
  DBUG_ENTER("mi_scan");
  /* Init all but update-flag */
  info->update&= (HA_STATE_CHANGED | HA_STATE_ROW_CHANGED);
  result= (*info->s->read_rnd)(info, buf, info->nextpos, 1);
  DBUG_RETURN(result);
}