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/* Copyright (c) 2000-2002, 2004-2007 MySQL AB
Use is subject to license terms
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; version 2 of the License.
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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335 USA */
#include "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_ENTER("heap_rfirst");
info->lastinx= inx;
info->key_version= info->s->key_version;
if (keyinfo->algorithm == HA_KEY_ALG_BTREE)
{
uchar *pos;
if ((pos = 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
{
info->update= HA_STATE_NO_KEY;
my_errno = HA_ERR_END_OF_FILE;
DBUG_RETURN(my_errno);
}
DBUG_RETURN(0);
}
else
{
/* We can't scan a non existing key value with hash index */
my_errno= HA_ERR_WRONG_COMMAND;
DBUG_RETURN(my_errno);
}
}
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