1 /* $NetBSD: bt_get.c,v 1.11 2007/02/03 23:46:09 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 1990, 1993, 1994 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Mike Olson. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #include <sys/cdefs.h> 36 #if defined(LIBC_SCCS) && !defined(lint) 37 #if 0 38 static char sccsid[] = "@(#)bt_get.c 8.6 (Berkeley) 7/20/94"; 39 #else 40 __RCSID("$NetBSD: bt_get.c,v 1.11 2007/02/03 23:46:09 christos Exp $"); 41 #endif 42 #endif /* LIBC_SCCS and not lint */ 43 44 #include "namespace.h" 45 #include <sys/types.h> 46 47 #include <assert.h> 48 #include <errno.h> 49 #include <stddef.h> 50 #include <stdio.h> 51 52 #include <db.h> 53 #include "btree.h" 54 55 /* 56 * __BT_GET -- Get a record from the btree. 57 * 58 * Parameters: 59 * dbp: pointer to access method 60 * key: key to find 61 * data: data to return 62 * flag: currently unused 63 * 64 * Returns: 65 * RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key not found. 66 */ 67 int 68 __bt_get(const DB *dbp, const DBT *key, DBT *data, u_int flags) 69 { 70 BTREE *t; 71 EPG *e; 72 int exact, status; 73 74 t = dbp->internal; 75 76 /* Toss any page pinned across calls. */ 77 if (t->bt_pinned != NULL) { 78 mpool_put(t->bt_mp, t->bt_pinned, 0); 79 t->bt_pinned = NULL; 80 } 81 82 /* Get currently doesn't take any flags. */ 83 if (flags) { 84 errno = EINVAL; 85 return (RET_ERROR); 86 } 87 88 if ((e = __bt_search(t, key, &exact)) == NULL) 89 return (RET_ERROR); 90 if (!exact) { 91 mpool_put(t->bt_mp, e->page, 0); 92 return (RET_SPECIAL); 93 } 94 95 status = __bt_ret(t, e, NULL, NULL, data, &t->bt_rdata, 0); 96 97 /* 98 * If the user is doing concurrent access, we copied the 99 * key/data, toss the page. 100 */ 101 if (F_ISSET(t, B_DB_LOCK)) 102 mpool_put(t->bt_mp, e->page, 0); 103 else 104 t->bt_pinned = e->page; 105 return (status); 106 } 107