Asterisk - The Open Source Telephony Project GIT-master-2de1a68
bt_get.c
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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. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the University of
19 * California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37#if defined(LIBC_SCCS) && !defined(lint)
38static char sccsid[] = "@(#)bt_get.c 8.6 (Berkeley) 7/20/94";
39#endif /* LIBC_SCCS and not lint */
40
41#include <sys/types.h>
42
43#include <errno.h>
44#include <stddef.h>
45#include <stdio.h>
46
47#include "../include/db.h"
48#include "btree.h"
49
50/*
51 * __BT_GET -- Get a record from the btree.
52 *
53 * Parameters:
54 * dbp: pointer to access method
55 * key: key to find
56 * data: data to return
57 * flag: currently unused
58 *
59 * Returns:
60 * RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key not found.
61 */
62int
63__bt_get(dbp, key, data, flags)
64 const DB *dbp;
65 const DBT *key;
66 DBT *data;
67 u_int flags;
68{
69 BTREE *t;
70 EPG *e;
71 int exact, status;
72
73 t = dbp->internal;
74
75 /* Toss any page pinned across calls. */
76 if (t->bt_pinned != NULL) {
77 mpool_put(t->bt_mp, t->bt_pinned, 0);
78 t->bt_pinned = NULL;
79 }
80
81 /* Get currently doesn't take any flags. */
82 if (flags) {
83 errno = EINVAL;
84 return (RET_ERROR);
85 }
86
87 if ((e = __bt_search(t, key, &exact)) == NULL)
88 return (RET_ERROR);
89 if (!exact) {
90 mpool_put(t->bt_mp, e->page, 0);
91 return (RET_SPECIAL);
92 }
93
94 status = __bt_ret(t, e, NULL, NULL, data, &t->bt_rdata, 0);
95
96 /*
97 * If the user is doing concurrent access, we copied the
98 * key/data, toss the page.
99 */
100 if (F_ISSET(t, B_DB_LOCK))
101 mpool_put(t->bt_mp, e->page, 0);
102 else
103 t->bt_pinned = e->page;
104 return (status);
105}
jack_status_t status
Definition: app_jack.c:146
int __bt_get(DB *dbp, const DBT *key, DBT *data, u_int flags) const
Definition: bt_get.c:63
EPG * __bt_search(BTREE *t, const DBT *key, int *exactp)
Definition: bt_search.c:66
int __bt_ret(BTREE *t, EPG *e, DBT *key, DBT *rkey, DBT *data, DBT *rdata, int copy)
Definition: bt_utils.c:67
#define F_ISSET(p, f)
Definition: btree.h:42
#define B_DB_LOCK
Definition: btree.h:385
#define RET_ERROR
Definition: db.h:51
#define RET_SPECIAL
Definition: db.h:53
static DB * dbp
Definition: hsearch.c:49
int errno
int mpool_put(MPOOL *mp, void *page, u_int flags)
Definition: mpool.c:251
#define NULL
Definition: resample.c:96
Definition: db.h:85
Definition: db.h:129
void * internal
Definition: db.h:137
Definition: btree.h:312
MPOOL * bt_mp
Definition: btree.h:313
PAGE * bt_pinned
Definition: btree.h:318
DBT bt_rdata
Definition: btree.h:333
Definition: btree.h:254
PAGE * page
Definition: btree.h:255