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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 */
/* L{ser f|reg}ende post med samma isam-nyckel */
#include "isamdef.h"
/*
L{ser f|reg}ende post med samma isamnyckel som f|reg}ende l{sning.
Man kan ha gjort write, update eller delete p} f|reg}ende post.
OBS! [ven om man {ndrade isamnyckeln p} f|reg}ende post l{ses
posten i avseende p} f|reg}ende isam-nyckel-l{sning !!
*/
int nisam_rprev(N_INFO *info, byte *buf, int inx)
{
int error;
register uint flag;
DBUG_ENTER("nisam_rprev");
if ((inx = _nisam_check_index(info,inx)) < 0)
DBUG_RETURN(-1);
flag=SEARCH_SMALLER; /* Read previous */
if (info->lastpos == NI_POS_ERROR && info->update & HA_STATE_NEXT_FOUND)
flag=0; /* Read last */
#ifndef NO_LOCKING
if (_nisam_readinfo(info,F_RDLCK,1)) DBUG_RETURN(-1);
#endif
if (!flag)
error=_nisam_search_last(info,info->s->keyinfo+inx,info->s->state.key_root[inx]);
else if (_nisam_test_if_changed(info) == 0)
error=_nisam_search_next(info,info->s->keyinfo+inx,info->lastkey,flag,
info->s->state.key_root[inx]);
else
error=_nisam_search(info,info->s->keyinfo+inx,info->lastkey,0,flag,
info->s->state.key_root[inx]);
info->update&= (HA_STATE_CHANGED | HA_STATE_ROW_CHANGED |
HA_STATE_BUFF_SAVED);
info->update|= HA_STATE_PREV_FOUND;
if (error && my_errno == HA_ERR_KEY_NOT_FOUND)
my_errno=HA_ERR_END_OF_FILE;
if ((*info->read_record)(info,info->lastpos,buf) >=0)
{
info->update|= HA_STATE_AKTIV; /* Record is read */
DBUG_RETURN(0);
}
DBUG_RETURN(-1);
} /* nisam_rprev */
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