mirror of
https://github.com/MariaDB/server.git
synced 2025-11-03 14:33:32 +03:00
106 lines
3.2 KiB
C
106 lines
3.2 KiB
C
/* 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 */
|
|
|
|
#include "myisamdef.h"
|
|
#include "rt_index.h"
|
|
|
|
/*
|
|
Read next row with the same key as previous read, but abort if
|
|
the key changes.
|
|
One may have done a write, update or delete of the previous row.
|
|
NOTE! Even if one changes the previous row, the next read is done
|
|
based on the position of the last used key!
|
|
*/
|
|
|
|
int mi_rnext_same(MI_INFO *info, byte *buf)
|
|
{
|
|
int error;
|
|
uint inx,not_used[2];
|
|
MI_KEYDEF *keyinfo;
|
|
DBUG_ENTER("mi_rnext_same");
|
|
|
|
if ((int) (inx=info->lastinx) < 0 || info->lastpos == HA_OFFSET_ERROR)
|
|
DBUG_RETURN(my_errno=HA_ERR_WRONG_INDEX);
|
|
keyinfo=info->s->keyinfo+inx;
|
|
if (fast_mi_readinfo(info))
|
|
DBUG_RETURN(my_errno);
|
|
|
|
if (info->s->concurrent_insert)
|
|
rw_rdlock(&info->s->key_root_lock[inx]);
|
|
|
|
switch (keyinfo->key_alg)
|
|
{
|
|
#ifdef HAVE_RTREE_KEYS
|
|
case HA_KEY_ALG_RTREE:
|
|
if ((error=rtree_find_next(info,inx,
|
|
myisam_read_vec[info->last_key_func])))
|
|
{
|
|
error=1;
|
|
my_errno=HA_ERR_END_OF_FILE;
|
|
info->lastpos= HA_OFFSET_ERROR;
|
|
break;
|
|
}
|
|
break;
|
|
#endif
|
|
case HA_KEY_ALG_BTREE:
|
|
default:
|
|
if (!(info->update & HA_STATE_RNEXT_SAME))
|
|
{
|
|
/* First rnext_same; Store old key */
|
|
memcpy(info->lastkey2,info->lastkey,info->last_rkey_length);
|
|
}
|
|
for (;;)
|
|
{
|
|
if ((error=_mi_search_next(info,keyinfo,info->lastkey,
|
|
info->lastkey_length,SEARCH_BIGGER,
|
|
info->s->state.key_root[inx])))
|
|
break;
|
|
if (ha_key_cmp(keyinfo->seg, info->lastkey, info->lastkey2,
|
|
info->last_rkey_length, SEARCH_FIND, not_used))
|
|
{
|
|
error=1;
|
|
my_errno=HA_ERR_END_OF_FILE;
|
|
info->lastpos= HA_OFFSET_ERROR;
|
|
break;
|
|
}
|
|
/* Skip rows that are inserted by other threads since we got a lock */
|
|
if (info->lastpos < info->state->data_file_length)
|
|
break;
|
|
}
|
|
}
|
|
if (info->s->concurrent_insert)
|
|
rw_unlock(&info->s->key_root_lock[inx]);
|
|
/* Don't clear if database-changed */
|
|
info->update&= (HA_STATE_CHANGED | HA_STATE_ROW_CHANGED);
|
|
info->update|= HA_STATE_NEXT_FOUND | HA_STATE_RNEXT_SAME;
|
|
|
|
if (error)
|
|
{
|
|
if (my_errno == HA_ERR_KEY_NOT_FOUND)
|
|
my_errno=HA_ERR_END_OF_FILE;
|
|
}
|
|
else if (!buf)
|
|
{
|
|
DBUG_RETURN(info->lastpos==HA_OFFSET_ERROR ? my_errno : 0);
|
|
}
|
|
else if (!(*info->read_record)(info,info->lastpos,buf))
|
|
{
|
|
info->update|= HA_STATE_AKTIV; /* Record is read */
|
|
DBUG_RETURN(0);
|
|
}
|
|
DBUG_RETURN(my_errno);
|
|
} /* mi_rnext */
|