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 * @(#)bt_get.c 8.6 (Berkeley) 7/20/94 37 */ 38 39 #include <sys/types.h> 40 41 #include <errno.h> 42 #include <stddef.h> 43 #include <stdio.h> 44 45 #include <db.h> 46 #include "btree.h" 47 48 /* 49 * __BT_GET -- Get a record from the btree. 50 * 51 * Parameters: 52 * dbp: pointer to access method 53 * key: key to find 54 * data: data to return 55 * flag: currently unused 56 * 57 * Returns: 58 * RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key not found. 59 */ 60 int 61 __bt_get(dbp, key, data, flags) 62 const DB *dbp; 63 const DBT *key; 64 DBT *data; 65 u_int flags; 66 { 67 BTREE *t; 68 EPG *e; 69 int exact, status; 70 71 t = dbp->internal; 72 73 /* Toss any page pinned across calls. */ 74 if (t->bt_pinned != NULL) { 75 mpool_put(t->bt_mp, t->bt_pinned, 0); 76 t->bt_pinned = NULL; 77 } 78 79 /* Get currently doesn't take any flags. */ 80 if (flags) { 81 errno = EINVAL; 82 return (RET_ERROR); 83 } 84 85 if ((e = __bt_search(t, key, &exact)) == NULL) 86 return (RET_ERROR); 87 if (!exact) { 88 mpool_put(t->bt_mp, e->page, 0); 89 return (RET_SPECIAL); 90 } 91 92 status = __bt_ret(t, e, NULL, NULL, data, &t->bt_rdata, 0); 93 94 /* 95 * If the user is doing concurrent access, we copied the 96 * key/data, toss the page. 97 */ 98 if (F_ISSET(t, B_DB_LOCK)) 99 mpool_put(t->bt_mp, e->page, 0); 100 else 101 t->bt_pinned = e->page; 102 return (status); 103 } 104