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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 p} basen av en isam_nyckel */
#include "isamdef.h"
/* Read a record using key */
/* Ordinary search_flag is 0 ; Give error if no record with key */
int nisam_rkey(N_INFO *info, byte *buf, int inx, const byte *key, uint key_len, enum ha_rkey_function search_flag)
{
uchar *key_buff;
ISAM_SHARE *share=info->s;
DBUG_ENTER("nisam_rkey");
DBUG_PRINT("enter",("base: %lx inx: %d search_flag: %d",
info,inx,search_flag));
if ((inx = _nisam_check_index(info,inx)) < 0)
DBUG_RETURN(-1);
info->update&= (HA_STATE_CHANGED | HA_STATE_ROW_CHANGED);
if (key_len >= (share->keyinfo[inx].base.keylength - share->rec_reflength)
&& !(info->s->keyinfo[inx].base.flag & HA_SPACE_PACK_USED))
key_len=USE_HOLE_KEY;
key_buff=info->lastkey+info->s->base.max_key_length;
key_len=_nisam_pack_key(info,(uint) inx,key_buff,(uchar*) key,key_len);
DBUG_EXECUTE("key",_nisam_print_key(DBUG_FILE,share->keyinfo[inx].seg,
(uchar*) key););
#ifndef NO_LOCKING
if (_nisam_readinfo(info,F_RDLCK,1))
goto err;
#endif
VOID(_nisam_search(info,info->s->keyinfo+inx,key_buff,key_len,
nisam_read_vec[search_flag],info->s->state.key_root[inx]));
if ((*info->read_record)(info,info->lastpos,buf) >= 0)
{
info->update|= HA_STATE_AKTIV; /* Record is read */
DBUG_RETURN(0);
}
info->lastpos = NI_POS_ERROR; /* Didn't find key */
VOID(_nisam_move_key(info->s->keyinfo+inx,info->lastkey,key_buff));
if (search_flag == HA_READ_AFTER_KEY)
info->update|=HA_STATE_NEXT_FOUND; /* Previous gives last row */
err:
DBUG_RETURN(-1);
} /* nisam_rkey */
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