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/* 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 */
/* Read a record with random-access. The position to the record must
get by N_INFO. The next record can be read with pos= -1 */
#include "isamdef.h"
/*
If filepos == NI_POS_ERROR, read next
Returns:
0 = Ok.
1 = Row was deleted
-1 = EOF (check errno to verify)
*/
int nisam_rrnd(N_INFO *info, byte *buf, register ulong filepos)
{
int skipp_deleted_blocks;
DBUG_ENTER("nisam_rrnd");
skipp_deleted_blocks=0;
if (filepos == NI_POS_ERROR)
{
skipp_deleted_blocks=1;
if (info->lastpos == NI_POS_ERROR) /* First read ? */
filepos= info->s->pack.header_length; /* Read first record */
else
filepos= info->nextpos;
}
info->lastinx= -1; /* Can't forward or backward */
/* Init all but update-flag */
info->update&= (HA_STATE_CHANGED | HA_STATE_ROW_CHANGED);
if (info->opt_flag & WRITE_CACHE_USED && flush_io_cache(&info->rec_cache))
DBUG_RETURN(my_errno);
DBUG_RETURN ((*info->s->read_rnd)(info,buf,filepos,skipp_deleted_blocks));
}
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