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/* $OpenBSD: bt_get.c,v 1.8 2005/08/05 13:02:59 espie Exp $ */ |
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/*- |
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* Copyright (c) 1990, 1993, 1994 |
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* The Regents of the University of California. All rights reserved. |
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* |
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* This code is derived from software contributed to Berkeley by |
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* Mike Olson. |
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* |
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* Redistribution and use in source and binary forms, with or without |
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* modification, are permitted provided that the following conditions |
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* are met: |
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* 1. Redistributions of source code must retain the above copyright |
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* notice, this list of conditions and the following disclaimer. |
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* 2. Redistributions in binary form must reproduce the above copyright |
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* notice, this list of conditions and the following disclaimer in the |
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* documentation and/or other materials provided with the distribution. |
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* 3. Neither the name of the University nor the names of its contributors |
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* may be used to endorse or promote products derived from this software |
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* without specific prior written permission. |
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* |
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
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* SUCH DAMAGE. |
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*/ |
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#include <sys/types.h> |
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#include <errno.h> |
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#include <stddef.h> |
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#include <stdio.h> |
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#include <db.h> |
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#include "btree.h" |
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/* |
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* __BT_GET -- Get a record from the btree. |
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* |
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* Parameters: |
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* dbp: pointer to access method |
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* key: key to find |
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* data: data to return |
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* flag: currently unused |
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* |
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* Returns: |
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* RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key not found. |
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*/ |
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int |
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__bt_get(const DB *dbp, const DBT *key, DBT *data, u_int flags) |
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{ |
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BTREE *t; |
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EPG *e; |
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int exact, status; |
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t = dbp->internal; |
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/* Toss any page pinned across calls. */ |
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if (t->bt_pinned != NULL) { |
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mpool_put(t->bt_mp, t->bt_pinned, 0); |
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t->bt_pinned = NULL; |
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} |
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/* Get currently doesn't take any flags. */ |
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if (flags) { |
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errno = EINVAL; |
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return (RET_ERROR); |
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} |
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if ((e = __bt_search(t, key, &exact)) == NULL) |
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return (RET_ERROR); |
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if (!exact) { |
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mpool_put(t->bt_mp, e->page, 0); |
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return (RET_SPECIAL); |
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} |
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status = __bt_ret(t, e, NULL, NULL, data, &t->bt_rdata, 0); |
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/* |
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* If the user is doing concurrent access, we copied the |
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* key/data, toss the page. |
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*/ |
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if (F_ISSET(t, B_DB_LOCK)) |
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mpool_put(t->bt_mp, e->page, 0); |
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else |
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t->bt_pinned = e->page; |
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return (status); |
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} |