74 lines
2.8 KiB
C++
74 lines
2.8 KiB
C++
/* Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved.
|
|
|
|
This program is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License, version 2.0,
|
|
as published by the Free Software Foundation.
|
|
|
|
This program is also distributed with certain software (including
|
|
but not limited to OpenSSL) that is licensed under separate terms,
|
|
as designated in a particular file or component or in included license
|
|
documentation. The authors of MySQL hereby grant you an additional
|
|
permission to link the program and your derivative works with the
|
|
separately licensed software that they have included with MySQL.
|
|
|
|
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, version 2.0, 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
|
|
|
|
#include "my_dbug.h"
|
|
#include "my_inttypes.h"
|
|
#include "storage/heap/heapdef.h"
|
|
|
|
/* Read first record with the current key */
|
|
|
|
int heap_rfirst(HP_INFO *info, uchar *record, int inx) {
|
|
HP_SHARE *share = info->s;
|
|
HP_KEYDEF *keyinfo = share->keydef + inx;
|
|
|
|
DBUG_TRACE;
|
|
info->lastinx = inx;
|
|
if (keyinfo->algorithm == HA_KEY_ALG_BTREE) {
|
|
uchar *pos;
|
|
|
|
if ((pos = (uchar *)tree_search_edge(&keyinfo->rb_tree, info->parents,
|
|
&info->last_pos,
|
|
offsetof(TREE_ELEMENT, left)))) {
|
|
memcpy(&pos, pos + (*keyinfo->get_key_length)(keyinfo, pos),
|
|
sizeof(uchar *));
|
|
info->current_ptr = pos;
|
|
memcpy(record, pos, (size_t)share->reclength);
|
|
/*
|
|
If we're performing index_first on a table that was taken from
|
|
table cache, info->lastkey_len is initialized to previous query.
|
|
Thus we set info->lastkey_len to proper value for subsequent
|
|
heap_rnext() calls.
|
|
This is needed for DELETE queries only, otherwise this variable is
|
|
not used.
|
|
Note that the same workaround may be needed for heap_rlast(), but
|
|
for now heap_rlast() is never used for DELETE queries.
|
|
*/
|
|
info->lastkey_len = 0;
|
|
info->update = HA_STATE_AKTIV;
|
|
} else {
|
|
set_my_errno(HA_ERR_END_OF_FILE);
|
|
return my_errno();
|
|
}
|
|
return 0;
|
|
} else {
|
|
if (!(info->s->records)) {
|
|
set_my_errno(HA_ERR_END_OF_FILE);
|
|
return my_errno();
|
|
}
|
|
DBUG_ASSERT(0); /* TODO fix it */
|
|
info->current_record = 0;
|
|
info->current_hash_ptr = 0;
|
|
info->update = HA_STATE_PREV_FOUND;
|
|
return heap_rnext(info, record);
|
|
}
|
|
}
|