1 /*-
2 * Copyright (c) 1990, 1993, 1994
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Mike Olson.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
32 * @(#)bt_get.c 8.6 (Berkeley) 7/20/94
33 * $FreeBSD: head/lib/libc/db/btree/bt_get.c 189291 2009-03-02 23:47:18Z delphij $
34 */
35
36 #include <sys/types.h>
37
38 #include <errno.h>
39 #include <stddef.h>
40 #include <stdio.h>
41
42 #include <db.h>
43 #include "btree.h"
44
45 /*
46 * __BT_GET -- Get a record from the btree.
47 *
48 * Parameters:
49 * dbp: pointer to access method
50 * key: key to find
51 * data: data to return
52 * flag: currently unused
53 *
54 * Returns:
55 * RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key not found.
56 */
57 int
__bt_get(const DB * dbp,const DBT * key,DBT * data,unsigned int flags)58 __bt_get(const DB *dbp, const DBT *key, DBT *data, unsigned int flags)
59 {
60 BTREE *t;
61 EPG *e;
62 int exact, status;
63
64 t = dbp->internal;
65
66 /* Toss any page pinned across calls. */
67 if (t->bt_pinned != NULL) {
68 mpool_put(t->bt_mp, t->bt_pinned, 0);
69 t->bt_pinned = NULL;
70 }
71
72 /* Get currently doesn't take any flags. */
73 if (flags) {
74 errno = EINVAL;
75 return (RET_ERROR);
76 }
77
78 if ((e = __bt_search(t, key, &exact)) == NULL)
79 return (RET_ERROR);
80 if (!exact) {
81 mpool_put(t->bt_mp, e->page, 0);
82 return (RET_SPECIAL);
83 }
84
85 status = __bt_ret(t, e, NULL, NULL, data, &t->bt_rdata, 0);
86
87 /*
88 * If the user is doing concurrent access, we copied the
89 * key/data, toss the page.
90 */
91 if (F_ISSET(t, B_DB_LOCK))
92 mpool_put(t->bt_mp, e->page, 0);
93 else
94 t->bt_pinned = e->page;
95 return (status);
96 }
97