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by brian
clean slate |
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/* Copyright (C) 2000-2002, 2004 MySQL AB
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; version 2 of the License.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
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#include "heapdef.h" |
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/* Read first record with the current key */
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int heap_rfirst(HP_INFO *info, uchar *record, int inx) |
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{
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HP_SHARE *share = info->s; |
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HP_KEYDEF *keyinfo = share->keydef + inx; |
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DBUG_ENTER("heap_rfirst"); |
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info->lastinx= inx; |
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if (keyinfo->algorithm == HA_KEY_ALG_BTREE) |
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{
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uchar *pos; |
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if ((pos = tree_search_edge(&keyinfo->rb_tree, info->parents, |
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&info->last_pos, offsetof(TREE_ELEMENT, left)))) |
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{
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memcpy(&pos, pos + (*keyinfo->get_key_length)(keyinfo, pos), |
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sizeof(uchar*)); |
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info->current_ptr = pos; |
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memcpy(record, pos, (size_t)share->reclength); |
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/*
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If we're performing index_first on a table that was taken from
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table cache, info->lastkey_len is initialized to previous query.
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Thus we set info->lastkey_len to proper value for subsequent
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heap_rnext() calls.
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This is needed for DELETE queries only, otherwise this variable is
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not used.
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Note that the same workaround may be needed for heap_rlast(), but
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for now heap_rlast() is never used for DELETE queries.
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*/
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info->lastkey_len= 0; |
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info->update = HA_STATE_AKTIV; |
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}
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else
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{
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my_errno = HA_ERR_END_OF_FILE; |
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DBUG_RETURN(my_errno); |
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}
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DBUG_RETURN(0); |
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}
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else
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{
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if (!(info->s->records)) |
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{
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my_errno=HA_ERR_END_OF_FILE; |
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DBUG_RETURN(my_errno); |
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}
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DBUG_ASSERT(0); /* TODO fix it */ |
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info->current_record=0; |
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info->current_hash_ptr=0; |
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info->update=HA_STATE_PREV_FOUND; |
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DBUG_RETURN(heap_rnext(info,record)); |
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}
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}
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