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Diffstat (limited to 'bdb/btree/bt_compare.c')
| -rw-r--r-- | bdb/btree/bt_compare.c | 211 |
1 files changed, 0 insertions, 211 deletions
diff --git a/bdb/btree/bt_compare.c b/bdb/btree/bt_compare.c deleted file mode 100644 index cbe2a1a7170..00000000000 --- a/bdb/btree/bt_compare.c +++ /dev/null @@ -1,211 +0,0 @@ -/*- - * See the file LICENSE for redistribution information. - * - * Copyright (c) 1996-2002 - * Sleepycat Software. All rights reserved. - */ -/* - * Copyright (c) 1990, 1993, 1994, 1995, 1996 - * Keith Bostic. All rights reserved. - */ -/* - * Copyright (c) 1990, 1993, 1994, 1995 - * The Regents of the University of California. All rights reserved. - * - * This code is derived from software contributed to Berkeley by - * Mike Olson. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * 3. Neither the name of the University nor the names of its contributors - * may be used to endorse or promote products derived from this software - * without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND - * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE - * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS - * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY - * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF - * SUCH DAMAGE. - */ - -#include "db_config.h" - -#ifndef lint -static const char revid[] = "$Id: bt_compare.c,v 11.17 2002/03/27 04:30:42 bostic Exp $"; -#endif /* not lint */ - -#ifndef NO_SYSTEM_INCLUDES -#include <sys/types.h> -#endif - -#include "db_int.h" -#include "dbinc/db_page.h" -#include "dbinc/btree.h" - -/* - * __bam_cmp -- - * Compare a key to a given record. - * - * PUBLIC: int __bam_cmp __P((DB *, const DBT *, PAGE *, - * PUBLIC: u_int32_t, int (*)(DB *, const DBT *, const DBT *), int *)); - */ -int -__bam_cmp(dbp, dbt, h, indx, func, cmpp) - DB *dbp; - const DBT *dbt; - PAGE *h; - u_int32_t indx; - int (*func)__P((DB *, const DBT *, const DBT *)); - int *cmpp; -{ - BINTERNAL *bi; - BKEYDATA *bk; - BOVERFLOW *bo; - DBT pg_dbt; - - /* - * Returns: - * < 0 if dbt is < page record - * = 0 if dbt is = page record - * > 0 if dbt is > page record - * - * !!! - * We do not clear the pg_dbt DBT even though it's likely to contain - * random bits. That should be okay, because the app's comparison - * routine had better not be looking at fields other than data/size. - * We don't clear it because we go through this path a lot and it's - * expensive. - */ - switch (TYPE(h)) { - case P_LBTREE: - case P_LDUP: - case P_LRECNO: - bk = GET_BKEYDATA(dbp, h, indx); - if (B_TYPE(bk->type) == B_OVERFLOW) - bo = (BOVERFLOW *)bk; - else { - pg_dbt.data = bk->data; - pg_dbt.size = bk->len; - *cmpp = func(dbp, dbt, &pg_dbt); - return (0); - } - break; - case P_IBTREE: - /* - * The following code guarantees that the left-most key on an - * internal page at any place in the tree sorts less than any - * user-specified key. The reason is that if we have reached - * this internal page, we know the user key must sort greater - * than the key we're storing for this page in any internal - * pages at levels above us in the tree. It then follows that - * any user-specified key cannot sort less than the first page - * which we reference, and so there's no reason to call the - * comparison routine. While this may save us a comparison - * routine call or two, the real reason for this is because - * we don't maintain a copy of the smallest key in the tree, - * so that we don't have to update all the levels of the tree - * should the application store a new smallest key. And, so, - * we may not have a key to compare, which makes doing the - * comparison difficult and error prone. - */ - if (indx == 0) { - *cmpp = 1; - return (0); - } - - bi = GET_BINTERNAL(dbp, h, indx); - if (B_TYPE(bi->type) == B_OVERFLOW) - bo = (BOVERFLOW *)(bi->data); - else { - pg_dbt.data = bi->data; - pg_dbt.size = bi->len; - *cmpp = func(dbp, dbt, &pg_dbt); - return (0); - } - break; - default: - return (__db_pgfmt(dbp->dbenv, PGNO(h))); - } - - /* - * Overflow. - */ - return (__db_moff(dbp, dbt, - bo->pgno, bo->tlen, func == __bam_defcmp ? NULL : func, cmpp)); -} - -/* - * __bam_defcmp -- - * Default comparison routine. - * - * PUBLIC: int __bam_defcmp __P((DB *, const DBT *, const DBT *)); - */ -int -__bam_defcmp(dbp, a, b) - DB *dbp; - const DBT *a, *b; -{ - size_t len; - u_int8_t *p1, *p2; - - COMPQUIET(dbp, NULL); - - /* - * Returns: - * < 0 if a is < b - * = 0 if a is = b - * > 0 if a is > b - * - * XXX - * If a size_t doesn't fit into a long, or if the difference between - * any two characters doesn't fit into an int, this routine can lose. - * What we need is a signed integral type that's guaranteed to be at - * least as large as a size_t, and there is no such thing. - */ - len = a->size > b->size ? b->size : a->size; - for (p1 = a->data, p2 = b->data; len--; ++p1, ++p2) - if (*p1 != *p2) - return ((long)*p1 - (long)*p2); - return ((long)a->size - (long)b->size); -} - -/* - * __bam_defpfx -- - * Default prefix routine. - * - * PUBLIC: size_t __bam_defpfx __P((DB *, const DBT *, const DBT *)); - */ -size_t -__bam_defpfx(dbp, a, b) - DB *dbp; - const DBT *a, *b; -{ - size_t cnt, len; - u_int8_t *p1, *p2; - - COMPQUIET(dbp, NULL); - - cnt = 1; - len = a->size > b->size ? b->size : a->size; - for (p1 = a->data, p2 = b->data; len--; ++p1, ++p2, ++cnt) - if (*p1 != *p2) - return (cnt); - - /* - * We know that a->size must be <= b->size, or they wouldn't be - * in this order. - */ - return (a->size < b->size ? a->size + 1 : a->size); -} |