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 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