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/* Copyright (C) 2000-2002, 2004 MySQL 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; 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
/* Read a record with random-access. The position to the record must
get by MI_INFO. The next record can be read with pos= MI_POS_ERROR */
#include "myisam_priv.h"
/*
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_RECORD_DELETED = Record is deleted.
HA_ERR_END_OF_FILE = EOF.
*/
int mi_rrnd(MI_INFO *info, unsigned char *buf, register my_off_t filepos)
{
bool skip_deleted_blocks;
skip_deleted_blocks=0;
if (filepos == HA_OFFSET_ERROR)
{
skip_deleted_blocks=1;
if (info->lastpos == HA_OFFSET_ERROR) /* First read ? */
filepos= info->s->pack.header_length; /* Read first record */
else
filepos= info->nextpos;
}
if (info->once_flags & RRND_PRESERVE_LASTINX)
info->once_flags&= ~RRND_PRESERVE_LASTINX;
else
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))
return(my_errno);
return ((*info->s->read_rnd)(info,buf,filepos,skip_deleted_blocks));
}
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