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-rw-r--r--db2/btree/bt_search.c369
1 files changed, 0 insertions, 369 deletions
diff --git a/db2/btree/bt_search.c b/db2/btree/bt_search.c
deleted file mode 100644
index 1f439a4261..0000000000
--- a/db2/btree/bt_search.c
+++ /dev/null
@@ -1,369 +0,0 @@
-/*-
- * See the file LICENSE for redistribution information.
- *
- * Copyright (c) 1996, 1997, 1998
- *	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. All advertising materials mentioning features or use of this software
- *    must display the following acknowledgement:
- *	This product includes software developed by the University of
- *	California, Berkeley and its contributors.
- * 4. 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 "config.h"
-
-#ifndef lint
-static const char sccsid[] = "@(#)bt_search.c	10.25 (Sleepycat) 12/16/98";
-#endif /* not lint */
-
-#ifndef NO_SYSTEM_INCLUDES
-#include <sys/types.h>
-
-#include <errno.h>
-#include <string.h>
-#endif
-
-#include "db_int.h"
-#include "db_page.h"
-#include "btree.h"
-
-/*
- * __bam_search --
- *	Search a btree for a key.
- *
- * PUBLIC: int __bam_search __P((DBC *,
- * PUBLIC:     const DBT *, u_int32_t, int, db_recno_t *, int *));
- */
-int
-__bam_search(dbc, key, flags, stop, recnop, exactp)
-	DBC *dbc;
-	const DBT *key;
-	u_int32_t flags;
-	int stop, *exactp;
-	db_recno_t *recnop;
-{
-	BTREE *t;
-	CURSOR *cp;
-	DB *dbp;
-	DB_LOCK lock;
-	PAGE *h;
-	db_indx_t base, i, indx, lim;
-	db_pgno_t pg;
-	db_recno_t recno;
-	int cmp, jump, ret, stack;
-
-	dbp = dbc->dbp;
-	cp = dbc->internal;
-	t = dbp->internal;
-	recno = 0;
-
-	BT_STK_CLR(cp);
-
-	/*
-	 * There are several ways we search a btree tree.  The flags argument
-	 * specifies if we're acquiring read or write locks, if we position
-	 * to the first or last item in a set of duplicates, if we return
-	 * deleted items, and if we are locking pairs of pages.  In addition,
-	 * if we're modifying record numbers, we have to lock the entire tree
-	 * regardless.  See btree.h for more details.
-	 *
-	 * If write-locking pages, we need to know whether or not to acquire a
-	 * write lock on a page before getting it.  This depends on how deep it
-	 * is in tree, which we don't know until we acquire the root page.  So,
-	 * if we need to lock the root page we may have to upgrade it later,
-	 * because we won't get the correct lock initially.
-	 *
-	 * Retrieve the root page.
-	 */
-	pg = PGNO_ROOT;
-	stack = F_ISSET(dbp, DB_BT_RECNUM) && LF_ISSET(S_STACK);
-	if ((ret = __bam_lget(dbc,
-	    0, pg, stack ? DB_LOCK_WRITE : DB_LOCK_READ, &lock)) != 0)
-		return (ret);
-	if ((ret = memp_fget(dbp->mpf, &pg, 0, &h)) != 0) {
-		(void)__BT_LPUT(dbc, lock);
-		return (ret);
-	}
-
-	/*
-	 * Decide if we need to save this page; if we do, write lock it.
-	 * We deliberately don't lock-couple on this call.  If the tree
-	 * is tiny, i.e., one page, and two threads are busily updating
-	 * the root page, we're almost guaranteed deadlocks galore, as
-	 * each one gets a read lock and then blocks the other's attempt
-	 * for a write lock.
-	 */
-	if (!stack &&
-	    ((LF_ISSET(S_PARENT) && (u_int8_t)(stop + 1) >= h->level) ||
-	    (LF_ISSET(S_WRITE) && h->level == LEAFLEVEL))) {
-		(void)memp_fput(dbp->mpf, h, 0);
-		(void)__BT_LPUT(dbc, lock);
-		if ((ret = __bam_lget(dbc, 0, pg, DB_LOCK_WRITE, &lock)) != 0)
-			return (ret);
-		if ((ret = memp_fget(dbp->mpf, &pg, 0, &h)) != 0) {
-			(void)__BT_LPUT(dbc, lock);
-			return (ret);
-		}
-		stack = 1;
-	}
-
-	for (;;) {
-		/*
-		 * Do a binary search on the current page.  If we're searching
-		 * a leaf page, we have to manipulate the indices in groups of
-		 * two.  If we're searching an internal page, they're an index
-		 * per page item.  If we find an exact match on a leaf page,
-		 * we're done.
-		 */
-		jump = TYPE(h) == P_LBTREE ? P_INDX : O_INDX;
-		for (base = 0,
-		    lim = NUM_ENT(h) / (db_indx_t)jump; lim != 0; lim >>= 1) {
-			indx = base + ((lim >> 1) * jump);
-			if ((cmp =
-			    __bam_cmp(dbp, key, h, indx, t->bt_compare)) == 0) {
-				if (TYPE(h) == P_LBTREE)
-					goto match;
-				goto next;
-			}
-			if (cmp > 0) {
-				base = indx + jump;
-				--lim;
-			}
-		}
-
-		/*
-		 * No match found.  Base is the smallest index greater than
-		 * key and may be zero or a last + O_INDX index.
-		 *
-		 * If it's a leaf page, return base as the "found" value.
-		 * Delete only deletes exact matches.
-		 */
-		if (TYPE(h) == P_LBTREE) {
-			*exactp = 0;
-
-			if (LF_ISSET(S_EXACT))
-				goto notfound;
-
-			/*
-			 * !!!
-			 * Possibly returning a deleted record -- DB_SET_RANGE,
-			 * DB_KEYFIRST and DB_KEYLAST don't require an exact
-			 * match, and we don't want to walk multiple pages here
-			 * to find an undeleted record.  This is handled in the
-			 * __bam_c_search() routine.
-			 */
-			BT_STK_ENTER(cp, h, base, lock, ret);
-			return (ret);
-		}
-
-		/*
-		 * If it's not a leaf page, record the internal page (which is
-		 * a parent page for the key).  Decrement the base by 1 if it's
-		 * non-zero so that if a split later occurs, the inserted page
-		 * will be to the right of the saved page.
-		 */
-		indx = base > 0 ? base - O_INDX : base;
-
-		/*
-		 * If we're trying to calculate the record number, sum up
-		 * all the record numbers on this page up to the indx point.
-		 */
-		if (recnop != NULL)
-			for (i = 0; i < indx; ++i)
-				recno += GET_BINTERNAL(h, i)->nrecs;
-
-next:		pg = GET_BINTERNAL(h, indx)->pgno;
-		if (stack) {
-			/* Return if this is the lowest page wanted. */
-			if (LF_ISSET(S_PARENT) && stop == h->level) {
-				BT_STK_ENTER(cp, h, indx, lock, ret);
-				return (ret);
-			}
-			BT_STK_PUSH(cp, h, indx, lock, ret);
-			if (ret != 0)
-				goto err;
-
-			if ((ret =
-			    __bam_lget(dbc, 0, pg, DB_LOCK_WRITE, &lock)) != 0)
-				goto err;
-		} else {
-			/*
-			 * Decide if we want to return a reference to the next
-			 * page in the return stack.  If so, lock it and never
-			 * unlock it.
-			 */
-			if ((LF_ISSET(S_PARENT) &&
-			    (u_int8_t)(stop + 1) >= (u_int8_t)(h->level - 1)) ||
-			    (h->level - 1) == LEAFLEVEL)
-				stack = 1;
-
-			(void)memp_fput(dbp->mpf, h, 0);
-
-			if ((ret =
-			    __bam_lget(dbc, 1, pg, stack && LF_ISSET(S_WRITE) ?
-			    DB_LOCK_WRITE : DB_LOCK_READ, &lock)) != 0)
-				goto err;
-		}
-		if ((ret = memp_fget(dbp->mpf, &pg, 0, &h)) != 0)
-			goto err;
-	}
-	/* NOTREACHED */
-
-match:	*exactp = 1;
-
-	/*
-	 * If we're trying to calculate the record number, add in the
-	 * offset on this page and correct for the fact that records
-	 * in the tree are 0-based.
-	 */
-	if (recnop != NULL)
-		*recnop = recno + (indx / P_INDX) + 1;
-
-	/*
-	 * If we got here, we know that we have a btree leaf page.
-	 *
-	 * If there are duplicates, go to the first/last one.  This is
-	 * safe because we know that we're not going to leave the page,
-	 * all duplicate sets that are not on overflow pages exist on a
-	 * single leaf page.
-	 */
-	if (LF_ISSET(S_DUPLAST))
-		while (indx < (db_indx_t)(NUM_ENT(h) - P_INDX) &&
-		    h->inp[indx] == h->inp[indx + P_INDX])
-			indx += P_INDX;
-	else
-		while (indx > 0 &&
-		    h->inp[indx] == h->inp[indx - P_INDX])
-			indx -= P_INDX;
-
-	/*
-	 * Now check if we are allowed to return deleted items; if not
-	 * find the next (or previous) non-deleted item.
-	 */
-	if (LF_ISSET(S_DELNO)) {
-		if (LF_ISSET(S_DUPLAST))
-			while (B_DISSET(GET_BKEYDATA(h, indx + O_INDX)->type) &&
-			    indx > 0 &&
-			    h->inp[indx] == h->inp[indx - P_INDX])
-				indx -= P_INDX;
-		else
-			while (B_DISSET(GET_BKEYDATA(h, indx + O_INDX)->type) &&
-			    indx < (db_indx_t)(NUM_ENT(h) - P_INDX) &&
-			    h->inp[indx] == h->inp[indx + P_INDX])
-				indx += P_INDX;
-
-		if (B_DISSET(GET_BKEYDATA(h, indx + O_INDX)->type))
-			goto notfound;
-	}
-
-	BT_STK_ENTER(cp, h, indx, lock, ret);
-	return (ret);
-
-notfound:
-	(void)memp_fput(dbp->mpf, h, 0);
-	(void)__BT_LPUT(dbc, lock);
-	ret = DB_NOTFOUND;
-
-err:	if (cp->csp > cp->sp) {
-		BT_STK_POP(cp);
-		__bam_stkrel(dbc, 0);
-	}
-	return (ret);
-}
-
-/*
- * __bam_stkrel --
- *	Release all pages currently held in the stack.
- *
- * PUBLIC: int __bam_stkrel __P((DBC *, int));
- */
-int
-__bam_stkrel(dbc, nolocks)
-	DBC *dbc;
-	int nolocks;
-{
-	CURSOR *cp;
-	DB *dbp;
-	EPG *epg;
-
-	dbp = dbc->dbp;
-	cp = dbc->internal;
-
-	/* Release inner pages first. */
-	for (epg = cp->sp; epg <= cp->csp; ++epg) {
-		if (epg->page != NULL)
-			(void)memp_fput(dbp->mpf, epg->page, 0);
-		if (epg->lock != LOCK_INVALID) {
-			if (nolocks)
-				(void)__BT_LPUT(dbc, epg->lock);
-			else
-				(void)__BT_TLPUT(dbc, epg->lock);
-		}
-	}
-
-	/* Clear the stack, all pages have been released. */
-	BT_STK_CLR(cp);
-
-	return (0);
-}
-
-/*
- * __bam_stkgrow --
- *	Grow the stack.
- *
- * PUBLIC: int __bam_stkgrow __P((CURSOR *));
- */
-int
-__bam_stkgrow(cp)
-	CURSOR *cp;
-{
-	EPG *p;
-	size_t entries;
-	int ret;
-
-	entries = cp->esp - cp->sp;
-
-	if ((ret = __os_calloc(entries * 2, sizeof(EPG), &p)) != 0)
-		return (ret);
-	memcpy(p, cp->sp, entries * sizeof(EPG));
-	if (cp->sp != cp->stack)
-		__os_free(cp->sp, entries * sizeof(EPG));
-	cp->sp = p;
-	cp->csp = p + entries;
-	cp->esp = p + entries * 2;
-	return (0);
-}