int mi_rnext(MI_INFO *info, uchar *buf, int inx)
{
int error,changed;
uint flag;
ICP_RESULT icp_res= ICP_MATCH;
uint update_mask= HA_STATE_NEXT_FOUND;
DBUG_ENTER("mi_rnext");
if ((inx = _mi_check_index(info,inx)) < 0)
DBUG_RETURN(my_errno);
flag=SEARCH_BIGGER; /* Read next */
if (info->lastpos == HA_OFFSET_ERROR && info->update & HA_STATE_PREV_FOUND)
flag=0; /* Read first */
if (fast_mi_readinfo(info))
DBUG_RETURN(my_errno);
if (info->s->concurrent_insert)
mysql_rwlock_rdlock(&info->s->key_root_lock[inx]);
changed=_mi_test_if_changed(info);
if (!flag)
{
switch(info->s->keyinfo[inx].key_alg){
#ifdef HAVE_RTREE_KEYS
case HA_KEY_ALG_RTREE:
error=rtree_get_first(info,inx,info->lastkey_length);
break;
#endif
case HA_KEY_ALG_BTREE:
default:
error=_mi_search_first(info,info->s->keyinfo+inx,
info->s->state.key_root[inx]);
break;
}
/*
"search first" failed. This means we have no pivot for
"search next", or in other words MI_INFO::lastkey is
likely uninitialized.
Normally SQL layer would never request "search next" if
"search first" failed. But HANDLER may do anything.
As mi_rnext() without preceding mi_rkey()/mi_rfirst()
equals to mi_rfirst(), we must restore original state
as if failing mi_rfirst() was not called.
*/
if (error)
update_mask|= HA_STATE_PREV_FOUND;
}
else
{
switch (info->s->keyinfo[inx].key_alg) {
#ifdef HAVE_RTREE_KEYS
case HA_KEY_ALG_RTREE:
/*
Note that rtree doesn't support that the table
may be changed since last call, so we do need
to skip rows inserted by other threads like in btree
*/
error= rtree_get_next(info,inx,info->lastkey_length);
break;
#endif
case HA_KEY_ALG_BTREE:
default:
if (!changed)
error= _mi_search_next(info,info->s->keyinfo+inx,info->lastkey,
info->lastkey_length,flag,
info->s->state.key_root[inx]);
else
error= _mi_search(info,info->s->keyinfo+inx,info->lastkey,
USE_WHOLE_KEY,flag, info->s->state.key_root[inx]);
}
}
if (!error)
{
while ((info->s->concurrent_insert &&
info->lastpos >= info->state->data_file_length) ||
(info->index_cond_func &&
(icp_res= mi_check_index_cond(info, inx, buf)) == ICP_NO_MATCH))
{
/*
If we are at the last key on the key page, allow writers to
access the index.
*/
if (info->int_keypos >= info->int_maxpos &&
mi_yield_and_check_if_killed(info, inx))
{
error= 1;
break;
}
/*
Skip rows that are either inserted by other threads since
we got a lock or do not match pushed index conditions
*/
if ((error=_mi_search_next(info,info->s->keyinfo+inx,
info->lastkey,
info->lastkey_length,
SEARCH_BIGGER,
info->s->state.key_root[inx])))
break;
}
}
if (info->s->concurrent_insert)
mysql_rwlock_unlock(&info->s->key_root_lock[inx]);
/* Don't clear if database-changed */
info->update&= (HA_STATE_CHANGED | HA_STATE_ROW_CHANGED);
info->update|= update_mask;
if (error || icp_res != ICP_MATCH)
{
fast_mi_writeinfo(info);
if (my_errno == HA_ERR_KEY_NOT_FOUND)
my_errno=HA_ERR_END_OF_FILE;
}
else if (!buf)
{
fast_mi_writeinfo(info);
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_PRINT("error",("Got error: %d, errno: %d",error, my_errno));
DBUG_RETURN(my_errno);
} /* mi_rnext */
int mi_rnext_same(MI_INFO *info, uchar *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)
{
set_my_errno(HA_ERR_WRONG_INDEX);
DBUG_RETURN(HA_ERR_WRONG_INDEX);
}
keyinfo=info->s->keyinfo+inx;
if (fast_mi_readinfo(info))
DBUG_RETURN(my_errno());
if (info->s->concurrent_insert)
mysql_rwlock_rdlock(&info->s->key_root_lock[inx]);
switch (keyinfo->key_alg)
{
case HA_KEY_ALG_RTREE:
if ((error=rtree_find_next(info,inx,
myisam_read_vec[info->last_key_func])))
{
error=1;
set_my_errno(HA_ERR_END_OF_FILE);
info->lastpos= HA_OFFSET_ERROR;
break;
}
break;
case HA_KEY_ALG_BTREE:
default:
if (info->set_rnext_same_key)
{
/* First rnext_same and lastkey is filled in mi_rkey */
memcpy(info->rnext_same_key, info->lastkey, info->last_rkey_length);
info->set_rnext_same_key= FALSE;
}
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->rnext_same_key,
info->last_rkey_length, SEARCH_FIND, not_used))
{
error=1;
set_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 &&
(!info->index_cond_func || mi_check_index_cond(info, inx, buf)))
break;
}
}
if (info->s->concurrent_insert)
mysql_rwlock_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;
if (error)
{
if (my_errno() == HA_ERR_KEY_NOT_FOUND)
set_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_same */
int mi_rprev(MI_INFO *info, uchar *buf, int inx)
{
int error,changed;
register uint flag;
MYISAM_SHARE *share=info->s;
DBUG_ENTER("mi_rprev");
if ((inx = _mi_check_index(info,inx)) < 0)
DBUG_RETURN(my_errno);
flag=SEARCH_SMALLER; /* Read previous */
if (info->lastpos == HA_OFFSET_ERROR && info->update & HA_STATE_NEXT_FOUND)
flag=0; /* Read last */
if (fast_mi_readinfo(info))
DBUG_RETURN(my_errno);
changed=_mi_test_if_changed(info);
if (share->concurrent_insert)
mysql_rwlock_rdlock(&share->key_root_lock[inx]);
if (!flag)
error=_mi_search_last(info, share->keyinfo+inx,
share->state.key_root[inx]);
else if (!changed)
error=_mi_search_next(info,share->keyinfo+inx,info->lastkey,
info->lastkey_length,flag,
share->state.key_root[inx]);
else
error=_mi_search(info,share->keyinfo+inx,info->lastkey,
USE_WHOLE_KEY, flag, share->state.key_root[inx]);
if (!error)
{
int res= 0;
while ((share->concurrent_insert &&
info->lastpos >= info->state->data_file_length) ||
(info->index_cond_func &&
!(res= mi_check_index_cond(info, inx, buf))))
{
/*
Skip rows that are either inserted by other threads since
we got a lock or do not match pushed index conditions
*/
if ((error=_mi_search_next(info,share->keyinfo+inx,info->lastkey,
info->lastkey_length,
SEARCH_SMALLER,
share->state.key_root[inx])))
break;
}
if (!error && res == 2)
{
if (share->concurrent_insert)
mysql_rwlock_unlock(&share->key_root_lock[inx]);
info->lastpos= HA_OFFSET_ERROR;
DBUG_RETURN(my_errno= HA_ERR_END_OF_FILE);
}
}
if (share->concurrent_insert)
{
if (!error)
{
while (info->lastpos >= info->state->data_file_length)
{
/* Skip rows that are inserted by other threads since we got a lock */
if ((error=_mi_search_next(info,share->keyinfo+inx,info->lastkey,
info->lastkey_length,
SEARCH_SMALLER,
share->state.key_root[inx])))
break;
}
}
mysql_rwlock_unlock(&share->key_root_lock[inx]);
}
info->update&= (HA_STATE_CHANGED | HA_STATE_ROW_CHANGED);
info->update|= HA_STATE_PREV_FOUND;
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_rprev */