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authorUlrich Drepper <drepper@redhat.com>1997-08-27 20:26:10 +0000
committerUlrich Drepper <drepper@redhat.com>1997-08-27 20:26:10 +0000
commit92f1da4da04a7a86ddee91be5eaf0b10c333ac64 (patch)
tree2a10ce9e4e407e7e5b5ca092ca0947d234b5ff60 /db2/btree/bt_delete.c
parent22be878ecbc66606371bd33258f56e6711e6ba7a (diff)
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1997-08-10 19:17  Philip Blundell  <Philip.Blundell@pobox.com>

	* nss/nss_db/db-XXX.c: Include <db_185.h> not <db.h>.  Somebody
	should update this to use the new db API.
	* nss/nss_db/db-netgrp.c: Likewise.
	* nss/nss_db/db-alias.c: Likewise.
	* db2/Makefile: Makefile for db-2.x in glibc.

1997-08-27 21:20  Ulrich Drepper  <drepper@cygnus.com>

	* csu/Makefile (before-compile): New goal.  Make sure abi-tag.h
	is generated.
	[$(elf)=yes] (asm-CPPFLAGS): Make sure abi-tag.h file can be found.

	* Makeconfig [$(build-omitfp)=yes] (CFLAGS-.o): Add
	-D__USE_STRING_INLINES.
	* string/string.f: Move strnlen optimization after inclusion of
	<bits/string.h>.  Include <bits/string.h> only if __USE_STRING_INLINES
	is defined.
	* sysdeps/generic/memcpy.c: Undef memcpy to allow macro of this name
	in <bits/string.h>.
	* sysdeps/generic/memset.c: Likewise.
	* sysdeps/i386/string.h: i386 optimized string functions.
	* sysdeps/i386/i486string.h: i486+ optimized string functions.

	* Makefile (subdirs): Change db to db2.
	* shlib-versions: Bump libdb verion number to 3.
	* include/db.h: Include from db2 directory.
	* include/db_185.h: New file.
	* sysdeps/i386/Makefile [$(subdirs)=db2] (CPPFLAGS): Add macros
	to provide spinlock information for db2.
	* sysdeps/m68k/m68020/Makefile: New file.  Likewise.
	* sysdeps/sparc/Makefile: New file.  Likewise.
	* sysdeps/unix/sysv/linux/Makefile [$(subdirs)=db2] (CPPFLAGS):
	Add -DHAVE_LLSEEK.
	* db2/config.h: Hand-edited config file for db2 in glibc.
	* db2/compat.h: New file from db-2.3.4.
	* db2/db.h: Likewise.
	* db2/db_185.h: Likewise.
	* db2/db_int.h: Likewise.
	* db2/makedb.c: Likewise.
	* db2/btree/bt_close.c: Likewise.
	* db2/btree/bt_compare.c: Likewise.
	* db2/btree/bt_conv.c: Likewise.
	* db2/btree/bt_cursor.c: Likewise.
	* db2/btree/bt_delete.c: Likewise.
	* db2/btree/bt_open.c: Likewise.
	* db2/btree/bt_page.c: Likewise.
	* db2/btree/bt_put.c: Likewise.
	* db2/btree/bt_rec.c: Likewise.
	* db2/btree/bt_recno.c: Likewise.
	* db2/btree/btree_auto.c: Likewise.
	* db2/btree/bt_rsearch.c: Likewise.
	* db2/btree/bt_search.c: Likewise.
	* db2/btree/bt_split.c: Likewise.
	* db2/btree/bt_stat.c: Likewise.
	* db2/btree/btree.src: Likewise.
	* db2/common/db_appinit.c: Likewise.
	* db2/common/db_err.c: Likewise.
	* db2/common/db_byteorder.c: Likewise.
	* db2/common/db_apprec.c: Likewise.
	* db2/common/db_salloc.c: Likewise.
	* db2/common/db_log2.c: Likewise.
	* db2/common/db_region.c: Likewise.
	* db2/common/db_shash.c: Likewise.
	* db2/db/db.c: Likewise.
	* db2/db/db.src: Likewise.
	* db2/db/db_conv.c: Likewise.
	* db2/db/db_dispatch.c: Likewise.
	* db2/db/db_dup.c: Likewise.
	* db2/db/db_overflow.c: Likewise.
	* db2/db/db_pr.c: Likewise.
	* db2/db/db_rec.c: Likewise.
	* db2/db/db_ret.c: Likewise.
	* db2/db/db_thread.c: Likewise.
	* db2/db/db_auto.c: Likewise.
	* db2/db185/db185.c: Likewise.
	* db2/db185/db185_int.h: Likewise.
	* db2/dbm/dbm.c: Likewise.
	* db2/hash/hash.c: Likewise.
	* db2/hash/hash.src: Likewise.
	* db2/hash/hash_page.c: Likewise.
	* db2/hash/hash_conv.c: Likewise.
	* db2/hash/hash_debug.c: Likewise.
	* db2/hash/hash_stat.c: Likewise.
	* db2/hash/hash_rec.c: Likewise.
	* db2/hash/hash_dup.c: Likewise.
	* db2/hash/hash_func.c: Likewise.
	* db2/hash/hash_auto.c: Likewise.
	* db2/include/mp.h: Likewise.
	* db2/include/btree.h: Likewise.
	* db2/include/db.h.src: Likewise.
	* db2/include/db_int.h.src: Likewise.
	* db2/include/db_shash.h: Likewise.
	* db2/include/db_swap.h: Likewise.
	* db2/include/db_185.h.src: Likewise.
	* db2/include/txn.h: Likewise.
	* db2/include/db_am.h: Likewise.
	* db2/include/shqueue.h: Likewise.
	* db2/include/hash.h: Likewise.
	* db2/include/db_dispatch.h: Likewise.
	* db2/include/lock.h: Likewise.
	* db2/include/db_page.h: Likewise.
	* db2/include/log.h: Likewise.
	* db2/include/db_auto.h: Likewise.
	* db2/include/btree_auto.h: Likewise.
	* db2/include/hash_auto.h: Likewise.
	* db2/include/log_auto.h: Likewise.
	* db2/include/txn_auto.h: Likewise.
	* db2/include/db_ext.h: Likewise.
	* db2/include/btree_ext.h: Likewise.
	* db2/include/clib_ext.h: Likewise.
	* db2/include/common_ext.h: Likewise.
	* db2/include/hash_ext.h: Likewise.
	* db2/include/lock_ext.h: Likewise.
	* db2/include/log_ext.h: Likewise.
	* db2/include/mp_ext.h: Likewise.
	* db2/include/mutex_ext.h: Likewise.
	* db2/include/os_ext.h: Likewise.
	* db2/include/txn_ext.h: Likewise.
	* db2/include/cxx_int.h: Likewise.
	* db2/include/db_cxx.h: Likewise.
	* db2/include/queue.h: Likewise.
	* db2/lock/lock.c: Likewise.
	* db2/lock/lock_conflict.c: Likewise.
	* db2/lock/lock_util.c: Likewise.
	* db2/lock/lock_deadlock.c: Likewise.
	* db2/log/log.c: Likewise.
	* db2/log/log_get.c: Likewise.
	* db2/log/log.src: Likewise.
	* db2/log/log_compare.c: Likewise.
	* db2/log/log_put.c: Likewise.
	* db2/log/log_rec.c: Likewise.
	* db2/log/log_archive.c: Likewise.
	* db2/log/log_register.c: Likewise.
	* db2/log/log_auto.c: Likewise.
	* db2/log/log_findckp.c: Likewise.
	* db2/mp/mp_bh.c: Likewise.
	* db2/mp/mp_fget.c: Likewise.
	* db2/mp/mp_fopen.c: Likewise.
	* db2/mp/mp_fput.c: Likewise.
	* db2/mp/mp_fset.c: Likewise.
	* db2/mp/mp_open.c: Likewise.
	* db2/mp/mp_region.c: Likewise.
	* db2/mp/mp_pr.c: Likewise.
	* db2/mp/mp_sync.c: Likewise.
	* db2/mutex/68020.gcc: Likewise.
	* db2/mutex/mutex.c: Likewise.
	* db2/mutex/README: Likewise.
	* db2/mutex/x86.gcc: Likewise.
	* db2/mutex/sparc.gcc: Likewise.
	* db2/mutex/uts4.cc.s: Likewise.
	* db2/mutex/alpha.dec: Likewise.
	* db2/mutex/alpha.gcc: Likewise.
	* db2/mutex/parisc.gcc: Likewise.
	* db2/mutex/parisc.hp: Likewise.
	* db2/os/db_os_abs.c: Likewise.
	* db2/os/db_os_dir.c: Likewise.
	* db2/os/db_os_fid.c: Likewise.
	* db2/os/db_os_lseek.c: Likewise.
	* db2/os/db_os_mmap.c: Likewise.
	* db2/os/db_os_open.c: Likewise.
	* db2/os/db_os_rw.c: Likewise.
	* db2/os/db_os_sleep.c: Likewise.
	* db2/os/db_os_stat.c: Likewise.
	* db2/os/db_os_unlink.c: Likewise.
	* db2/txn/txn.c: Likewise.
	* db2/txn/txn.src: Likewise.
	* db2/txn/txn_rec.c: Likewise.
	* db2/txn/txn_auto.c: Likewise.
	* db2/clib/getlong.c: Likewise.
	* db2/progs/db_archive/db_archive.c: Likewise.
	* db2/progs/db_checkpoint/db_checkpoint.c: Likewise.
	* db2/progs/db_deadlock/db_deadlock.c: Likewise.
	* db2/progs/db_dump/db_dump.c: Likewise.
	* db2/progs/db_dump185/db_dump185.c: Likewise.
	* db2/progs/db_load/db_load.c: Likewise.
	* db2/progs/db_printlog/db_printlog.c: Likewise.
	* db2/progs/db_recover/db_recover.c: Likewise.
	* db2/progs/db_stat/db_stat.c: Likewise.

	* libio/stdio.h [__cplusplus] (__STDIO_INLINE): Define as inline.

	* po/de.po, po/sv.po: Update from 2.0.5 translations.

	* sysdeps/unix/sysv/linux/netinet/tcp.h: Pretty print.

	* sunrpc/rpc/xdr.h (XDR): Don't define argument of x_destroy callback
	as const.
	* sunrpc/xdr_mem.c (xdrmem_destroy): Don't define argument as const.
	* sunrpx/xdr_rec.c (xdrrec_destroy): Likewise.
	* sunrpx/xdr_stdio.c (xdrstdio_destroy): Likewise.

1997-08-27 18:47  Ulrich Drepper  <drepper@cygnus.com>

	* sysdeps/unix/sysv/linux/if_index.c: Include <errno.h>.
	Reported by Benjamin Kosnik <bkoz@cygnus.com>.

1997-08-27 02:27  Roland McGrath  <roland@baalperazim.frob.com>

	* abi-tags: New file.
	* csu/Makefile (distribute): Remove abi-tag.h.
	($(objpfx)abi-tag.h): New target.
	* Makefile (distribute): Add abi-tags.
	* sysdeps/unix/sysv/linux/abi-tag.h: File removed.
	* sysdeps/mach/hurd/abi-tag.h: File removed.
	* sysdeps/stub/abi-tag.h: File removed.

1997-08-25  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* sysdeps/unix/make-syscalls.sh: Change output so that it
	generates compilation rules only for the currently selected object
	suffixes.

1997-08-25  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* sysdeps/m68k/dl-machine.h (RTLD_START): Switch back to previous
	section to avoid confusing the compiler.
	* sysdeps/alpha/dl-machine.h (RTLD_START): Likewise.
	* sysdeps/i386/dl-machine.h (RTLD_START): Likewise.
	* sysdeps/mips/dl-machine.h (RTLD_START): Likewise.
	* sysdeps/mips/mips64/dl-machine.h (RTLD_START): Likewise.
	* sysdeps/sparc/sparc32/dl-machine.h (RTLD_START): Likewise.

	* sysdeps/m68k/dl-machine.h (elf_machine_load_address): Use a GOT
	relocation instead of a constant to avoid text relocation.
	(ELF_MACHINE_BEFORE_RTLD_RELOC): Removed.
	(RTLD_START): Declare global labels as functions and add size
	directive.

1997-08-25 17:01  Ulrich Drepper  <drepper@cygnus.com>

	* sysdeps/i386/bits/select.h: Correct assembler versions to work even
	for descriptors >= 32.

	* stdlib/alloca.h: Don't define alloca to __alloca since if gcc
	is used __alloca is not defined to __builtin_alloca and so might
	not be available.
	Reported by Uwe Ohse <uwe@ohse.de>.

	* sysdeps/unix/sysv/linux/sys/sysmacros.h: Define macros in a special
	way if gcc is not used and so dev_t is an array.
	Reported by Uwe Ohse <uwe@ohse.de>.

1997-08-23  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* manual/libc.texinfo: Reorder chapters to match logical order.

1997-08-25 12:22  Ulrich Drepper  <drepper@cygnus.com>

	* sunrpc/rpc/xdr.h: Change name of parameters in prototypes of
	xdr_reference, xdrmem_create, and xdrstdio_create because of clash
	with g++ internal symbols.
	Patch by Sudish Joseph <sj@eng.mindspring.net>.

	* elf/dl-deps.c: Implement handling of DT_FILTER.
Diffstat (limited to 'db2/btree/bt_delete.c')
-rw-r--r--db2/btree/bt_delete.c607
1 files changed, 607 insertions, 0 deletions
diff --git a/db2/btree/bt_delete.c b/db2/btree/bt_delete.c
new file mode 100644
index 0000000000..e7ec4dfe3e
--- /dev/null
+++ b/db2/btree/bt_delete.c
@@ -0,0 +1,607 @@
+/*-
+ * See the file LICENSE for redistribution information.
+ *
+ * Copyright (c) 1996, 1997
+ *	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_delete.c	10.18 (Sleepycat) 8/24/97";
+#endif /* not lint */
+
+#ifndef NO_SYSTEM_INCLUDES
+#include <sys/types.h>
+
+#include <stdio.h>
+#include <string.h>
+#endif
+
+#include "db_int.h"
+#include "db_page.h"
+#include "btree.h"
+
+static int __bam_dpages __P((DB *, BTREE *));
+
+/*
+ * __bam_delete --
+ *	Delete the items referenced by a key.
+ *
+ * PUBLIC: int __bam_delete __P((DB *, DB_TXN *, DBT *, int));
+ */
+int
+__bam_delete(argdbp, txn, key, flags)
+	DB *argdbp;
+	DB_TXN *txn;
+	DBT *key;
+	int flags;
+{
+	BTREE *t;
+	DB *dbp;
+	PAGE *h;
+	db_indx_t cnt, i, indx;
+	int dpage, exact, ret, stack;
+
+	DEBUG_LWRITE(argdbp, txn, "bam_delete", key, NULL, flags);
+
+	stack = 0;
+
+	/* Check for invalid flags. */
+	if ((ret =
+	    __db_delchk(argdbp, flags, F_ISSET(argdbp, DB_AM_RDONLY))) != 0)
+		return (ret);
+
+	GETHANDLE(argdbp, txn, &dbp, ret);
+	t = dbp->internal;
+
+	/* Search the tree for the key; delete only deletes exact matches. */
+	if ((ret = __bam_search(dbp, key, S_DELETE, 1, NULL, &exact)) != 0)
+		goto err;
+	stack = 1;
+	h = t->bt_csp->page;
+	indx = t->bt_csp->indx;
+
+	/* Delete the key/data pair, including any duplicates. */
+	for (cnt = 1, i = indx;; ++cnt)
+		if ((i += P_INDX) >= NUM_ENT(h) || h->inp[i] != h->inp[indx])
+			break;
+	for (; cnt > 0; --cnt, ++t->lstat.bt_deleted)
+		if (__bam_ca_delete(dbp, h->pgno, indx, NULL) != 0) {
+			GET_BKEYDATA(h, indx + O_INDX)->deleted = 1;
+			indx += P_INDX;
+		} else if ((ret = __bam_ditem(dbp, h, indx)) != 0 ||
+		    (ret = __bam_ditem(dbp, h, indx)) != 0)
+			goto err;
+
+	/* If we're using record numbers, update internal page record counts. */
+	if (F_ISSET(dbp, DB_BT_RECNUM) && (ret = __bam_adjust(dbp, t, -1)) != 0)
+		goto err;
+
+	/* If the page is now empty, delete it. */
+	dpage = NUM_ENT(h) == 0 && h->pgno != PGNO_ROOT;
+
+	__bam_stkrel(dbp);
+	stack = 0;
+
+	ret = dpage ? __bam_dpage(dbp, key) : 0;
+
+err:	if (stack)
+		__bam_stkrel(dbp);
+	PUTHANDLE(dbp);
+	return (ret);
+}
+
+/*
+ * __ram_delete --
+ *	Delete the items referenced by a key.
+ *
+ * PUBLIC: int __ram_delete __P((DB *, DB_TXN *, DBT *, int));
+ */
+int
+__ram_delete(argdbp, txn, key, flags)
+	DB *argdbp;
+	DB_TXN *txn;
+	DBT *key;
+	int flags;
+{
+	BKEYDATA bk;
+	BTREE *t;
+	DB *dbp;
+	DBT hdr, data;
+	PAGE *h;
+	db_indx_t indx;
+	db_recno_t recno;
+	int exact, ret, stack;
+
+	stack = 0;
+
+	/* Check for invalid flags. */
+	if ((ret =
+	    __db_delchk(argdbp, flags, F_ISSET(argdbp, DB_AM_RDONLY))) != 0)
+		return (ret);
+
+	GETHANDLE(argdbp, txn, &dbp, ret);
+	t = dbp->internal;
+
+	/* Check the user's record number and fill in as necessary. */
+	if ((ret = __ram_getno(argdbp, key, &recno, 0)) != 0)
+		goto err;
+
+	/* Search the tree for the key; delete only deletes exact matches. */
+	if ((ret = __bam_rsearch(dbp, &recno, S_DELETE, 1, &exact)) != 0)
+		goto err;
+	if (!exact) {
+		ret = DB_NOTFOUND;
+		goto err;
+	}
+
+	h = t->bt_csp->page;
+	indx = t->bt_csp->indx;
+	stack = 1;
+
+	/* If the record has already been deleted, we couldn't have found it. */
+	if (GET_BKEYDATA(h, indx)->deleted) {
+		ret = DB_KEYEMPTY;
+		goto done;
+	}
+
+	/*
+	 * If we're not renumbering records, replace the record with a marker
+	 * and return.
+	 */
+	if (!F_ISSET(dbp, DB_RE_RENUMBER)) {
+		if ((ret = __bam_ditem(dbp, h, indx)) != 0)
+			goto err;
+
+		bk.deleted = 1;
+		bk.type = B_KEYDATA;
+		bk.len = 0;
+		memset(&hdr, 0, sizeof(hdr));
+		hdr.data = &bk;
+		hdr.size = SSZA(BKEYDATA, data);
+		memset(&data, 0, sizeof(data));
+		data.data = (char *) "";
+		data.size = 0;
+		if ((ret = __db_pitem(dbp,
+		    h, indx, BKEYDATA_SIZE(0), &hdr, &data)) != 0)
+			goto err;
+
+		++t->lstat.bt_deleted;
+		goto done;
+	}
+
+	/* Delete the item. */
+	if ((ret = __bam_ditem(dbp, h, indx)) != 0)
+		goto err;
+
+	++t->lstat.bt_deleted;
+	if (t->bt_recno != NULL)
+		F_SET(t->bt_recno, RECNO_MODIFIED);
+
+	/* Adjust the counts. */
+	__bam_adjust(dbp, t, -1);
+
+	/* Adjust the cursors. */
+	__ram_ca(dbp, recno, CA_DELETE);
+
+	/*
+	 * If the page is now empty, delete it -- we have the whole tree
+	 * locked, so there are no preparations to make.  Else, release
+	 * the pages.
+	 */
+	if (NUM_ENT(h) == 0 && h->pgno != PGNO_ROOT) {
+		stack = 0;
+		ret = __bam_dpages(dbp, t);
+	}
+
+done:
+err:	if (stack)
+		__bam_stkrel(dbp);
+
+	PUTHANDLE(dbp);
+	return (ret);
+}
+
+/*
+ * __bam_ditem --
+ *	Delete one or more entries from a page.
+ *
+ * PUBLIC: int __bam_ditem __P((DB *, PAGE *, u_int32_t));
+ */
+int
+__bam_ditem(dbp, h, indx)
+	DB *dbp;
+	PAGE *h;
+	u_int32_t indx;
+{
+	BINTERNAL *bi;
+	BKEYDATA *bk;
+	BOVERFLOW *bo;
+	u_int32_t nbytes;
+	int ret;
+
+	switch (TYPE(h)) {
+	case P_IBTREE:
+		bi = GET_BINTERNAL(h, indx);
+		switch (bi->type) {
+		case B_DUPLICATE:
+		case B_OVERFLOW:
+			nbytes = BINTERNAL_SIZE(bi->len);
+			goto offpage;
+		case B_KEYDATA:
+			nbytes = BKEYDATA_SIZE(bi->len);
+			break;
+		default:
+			return (__db_pgfmt(dbp, h->pgno));
+		}
+		break;
+	case P_IRECNO:
+		nbytes = RINTERNAL_SIZE;
+		break;
+	case P_LBTREE:
+		/*
+		 * If it's a duplicate key, discard the index and don't touch
+		 * the actual page item.  This works because no data item can
+		 * have an index that matches any other index so even if the
+		 * data item is in an index "slot", it won't match any other
+		 * index.
+		 */
+		if (!(indx % 2)) {
+			if (indx > 0 && h->inp[indx] == h->inp[indx - P_INDX])
+				return (__bam_adjindx(dbp,
+				    h, indx, indx - P_INDX, 0));
+			if (indx < (u_int32_t)(NUM_ENT(h) - P_INDX) &&
+			    h->inp[indx] == h->inp[indx + P_INDX])
+				return (__bam_adjindx(dbp,
+				    h, indx, indx + O_INDX, 0));
+		}
+		/* FALLTHROUGH */
+	case P_LRECNO:
+		bk = GET_BKEYDATA(h, indx);
+		switch (bk->type) {
+		case B_DUPLICATE:
+		case B_OVERFLOW:
+			nbytes = BOVERFLOW_SIZE;
+
+offpage:		/* Delete duplicate/offpage chains. */
+			bo = GET_BOVERFLOW(h, indx);
+			if (bo->type == B_DUPLICATE) {
+				if ((ret =
+				    __db_ddup(dbp, bo->pgno, __bam_free)) != 0)
+					return (ret);
+			} else
+				if ((ret =
+				    __db_doff(dbp, bo->pgno, __bam_free)) != 0)
+					return (ret);
+			break;
+		case B_KEYDATA:
+			nbytes = BKEYDATA_SIZE(bk->len);
+			break;
+		default:
+			return (__db_pgfmt(dbp, h->pgno));
+		}
+		break;
+	default:
+		return (__db_pgfmt(dbp, h->pgno));
+	}
+
+	/* Delete the item. */
+	if ((ret = __db_ditem(dbp, h, indx, nbytes)) != 0)
+		return (ret);
+
+	/* Mark the page dirty. */
+	return (memp_fset(dbp->mpf, h, DB_MPOOL_DIRTY));
+}
+
+/*
+ * __bam_adjindx --
+ *	Adjust an index on the page.
+ *
+ * PUBLIC: int __bam_adjindx __P((DB *, PAGE *, u_int32_t, u_int32_t, int));
+ */
+int
+__bam_adjindx(dbp, h, indx, indx_copy, is_insert)
+	DB *dbp;
+	PAGE *h;
+	u_int32_t indx, indx_copy;
+	int is_insert;
+{
+	db_indx_t copy;
+	int ret;
+
+	/* Log the change. */
+	if (DB_LOGGING(dbp) &&
+	    (ret = __bam_adj_log(dbp->dbenv->lg_info, dbp->txn, &LSN(h),
+	    0, dbp->log_fileid, PGNO(h), &LSN(h), indx, indx_copy,
+	    (u_int32_t)is_insert)) != 0)
+		return (ret);
+
+	if (is_insert) {
+		copy = h->inp[indx_copy];
+		if (indx != NUM_ENT(h))
+			memmove(&h->inp[indx + O_INDX], &h->inp[indx],
+			    sizeof(db_indx_t) * (NUM_ENT(h) - indx));
+		h->inp[indx] = copy;
+		++NUM_ENT(h);
+	} else {
+		--NUM_ENT(h);
+		if (indx != NUM_ENT(h))
+			memmove(&h->inp[indx], &h->inp[indx + O_INDX],
+			    sizeof(db_indx_t) * (NUM_ENT(h) - indx));
+	}
+
+	/* Mark the page dirty. */
+	ret = memp_fset(dbp->mpf, h, DB_MPOOL_DIRTY);
+
+	/* Adjust the cursors. */
+	__bam_ca_di(dbp, h->pgno, indx, is_insert ? 1 : -1);
+	return (0);
+}
+
+/*
+ * __bam_dpage --
+ *	Delete a page from the tree.
+ *
+ * PUBLIC: int __bam_dpage __P((DB *, const DBT *));
+ */
+int
+__bam_dpage(dbp, key)
+	DB *dbp;
+	const DBT *key;
+{
+	BTREE *t;
+	DB_LOCK lock;
+	PAGE *h;
+	db_pgno_t pgno;
+	int exact, level, ret;
+
+	ret = 0;
+	t = dbp->internal;
+
+	/*
+	 * The locking protocol is that we acquire locks by walking down the
+	 * tree, to avoid the obvious deadlocks.
+	 *
+	 * Call __bam_search to reacquire the empty leaf page, but this time
+	 * get both the leaf page and it's parent, locked.  Walk back up the
+	 * tree, until we have the top pair of pages that we want to delete.
+	 * Once we have the top page that we want to delete locked, lock the
+	 * underlying pages and check to make sure they're still empty.  If
+	 * they are, delete them.
+	 */
+	for (level = LEAFLEVEL;; ++level) {
+		/* Acquire a page and its parent, locked. */
+		if ((ret =
+		    __bam_search(dbp, key, S_WRPAIR, level, NULL, &exact)) != 0)
+			return (ret);
+
+		/*
+		 * If we reach the root or the page isn't going to be empty
+		 * when we delete one record, quit.
+		 */
+		h = t->bt_csp[-1].page;
+		if (h->pgno == PGNO_ROOT || NUM_ENT(h) != 1)
+			break;
+
+		/* Release the two locked pages. */
+		(void)memp_fput(dbp->mpf, t->bt_csp[-1].page, 0);
+		(void)__BT_TLPUT(dbp, t->bt_csp[-1].lock);
+		(void)memp_fput(dbp->mpf, t->bt_csp[0].page, 0);
+		(void)__BT_TLPUT(dbp, t->bt_csp[0].lock);
+	}
+
+	/*
+	 * Leave the stack pointer one after the last entry, we may be about
+	 * to push more items on the stack.
+	 */
+	++t->bt_csp;
+
+	/*
+	 * t->bt_csp[-2].page is the top page, which we're not going to delete,
+	 * and t->bt_csp[-1].page is the first page we are going to delete.
+	 *
+	 * Walk down the chain, acquiring the rest of the pages until we've
+	 * retrieved the leaf page.  If we find any pages that aren't going
+	 * to be emptied by the delete, someone else added something while we
+	 * were walking the tree, and we discontinue the delete.
+	 */
+	for (h = t->bt_csp[-1].page;;) {
+		if (ISLEAF(h)) {
+			if (NUM_ENT(h) != 0)
+				goto release;
+			break;
+		} else
+			if (NUM_ENT(h) != 1)
+				goto release;
+
+		/*
+		 * Get the next page, write lock it and push it onto the stack.
+		 * We know it's index 0, because it can only have one element.
+		 */
+		pgno = TYPE(h) == P_IBTREE ?
+		    GET_BINTERNAL(h, 0)->pgno : GET_RINTERNAL(h, 0)->pgno;
+
+		if ((ret = __bam_lget(dbp, 0, pgno, DB_LOCK_WRITE, &lock)) != 0)
+			goto release;
+		if ((ret = __bam_pget(dbp, &h, &pgno, 0)) != 0)
+			goto release;
+		BT_STK_PUSH(t, h, 0, lock, ret);
+		if (ret != 0)
+			goto release;
+	}
+
+	BT_STK_POP(t);
+	return (__bam_dpages(dbp, t));
+
+release:
+	/* Discard any locked pages and return. */
+	BT_STK_POP(t);
+	__bam_stkrel(dbp);
+	return (ret);
+}
+
+/*
+ * __bam_dpages --
+ *	Delete a set of locked pages.
+ */
+static int
+__bam_dpages(dbp, t)
+	DB *dbp;
+	BTREE *t;
+{
+	DBT a, b;
+	DB_LOCK lock;
+	EPG *epg;
+	PAGE *h;
+	db_pgno_t pgno;
+	db_recno_t rcnt;
+	int ret;
+
+	rcnt = 0;				/* XXX: Shut the compiler up. */
+	epg = t->bt_sp;
+
+	/*
+	 * !!!
+	 * There is an interesting deadlock situation here.  We have to relink
+	 * the leaf page chain around the leaf page being deleted.  Consider
+	 * a cursor walking through the leaf pages, that has the previous page
+	 * read-locked and is waiting on a lock for the page we're deleting.
+	 * It will deadlock here.  This is a problem, because if our process is
+	 * selected to resolve the deadlock, we'll leave an empty leaf page
+	 * that we can never again access by walking down the tree.  So, before
+	 * we unlink the subtree, we relink the leaf page chain.
+	 */
+	if ((ret = __db_relink(dbp, t->bt_csp->page, NULL, 1)) != 0)
+		goto release;
+
+	/*
+	 * We have the entire stack of deletable pages locked.  Start from the
+	 * top of the tree and move to the bottom, as it's better to release
+	 * the inner pages as soon as possible.
+	 */
+	if ((ret = __bam_ditem(dbp, epg->page, epg->indx)) != 0)
+		goto release;
+
+	/*
+	 * If we deleted the next-to-last item from the root page, the tree
+	 * has collapsed a level.  Try and write lock the remaining root + 1
+	 * page and copy it onto the root page.  If we can't get the lock,
+	 * that's okay, the tree just stays a level deeper than we'd like.
+	 */
+	h = epg->page;
+	if (h->pgno == PGNO_ROOT && NUM_ENT(h) == 1) {
+		pgno = TYPE(epg->page) == P_IBTREE ?
+		    GET_BINTERNAL(epg->page, 0)->pgno :
+		    GET_RINTERNAL(epg->page, 0)->pgno;
+		if ((ret = __bam_lget(dbp, 0, pgno, DB_LOCK_WRITE, &lock)) != 0)
+			goto release;
+		if ((ret = __bam_pget(dbp, &h, &pgno, 0)) != 0)
+			goto release;
+
+		/* Log the change. */
+		if (DB_LOGGING(dbp)) {
+			memset(&a, 0, sizeof(a));
+			a.data = h;
+			a.size = dbp->pgsize;
+			memset(&b, 0, sizeof(b));
+			b.data = P_ENTRY(epg->page, 0);
+			b.size = BINTERNAL_SIZE(((BINTERNAL *)b.data)->len);
+			__bam_rsplit_log(dbp->dbenv->lg_info, dbp->txn,
+			   &h->lsn, 0, dbp->log_fileid, h->pgno, &a, &b,
+			   &epg->page->lsn);
+		}
+
+		/*
+		 * Make the switch.
+		 *
+		 * One fixup -- if the tree has record numbers and we're not
+		 * converting to a leaf page, we have to preserve the total
+		 * record count.
+		 */
+		if (TYPE(h) == P_IRECNO ||
+		    (TYPE(h) == P_IBTREE && F_ISSET(dbp, DB_BT_RECNUM)))
+			rcnt = RE_NREC(epg->page);
+		memcpy(epg->page, h, dbp->pgsize);
+		epg->page->pgno = PGNO_ROOT;
+		if (TYPE(h) == P_IRECNO ||
+		    (TYPE(h) == P_IBTREE && F_ISSET(dbp, DB_BT_RECNUM)))
+			RE_NREC_SET(epg->page, rcnt);
+
+		/* Free the last page in that level of the btree. */
+		++t->lstat.bt_freed;
+		(void)__bam_free(dbp, h);
+
+		/* Adjust the cursors. */
+		__bam_ca_move(dbp, t, h->pgno, PGNO_ROOT);
+
+		(void)__BT_TLPUT(dbp, lock);
+	}
+
+	/* Release the top page in the subtree. */
+	(void)memp_fput(dbp->mpf, epg->page, 0);
+	(void)__BT_TLPUT(dbp, epg->lock);
+
+	/*
+	 * Free the rest of the pages.
+	 *
+	 * XXX
+	 * Don't bother checking for errors.  We've unlinked the subtree from
+	 * the tree, and there's no possibility of recovery.
+	 */
+	for (; ++epg <= t->bt_csp; ++t->lstat.bt_freed) {
+		if (NUM_ENT(epg->page) != 0)
+			(void)__bam_ditem(dbp, epg->page, epg->indx);
+
+		(void)__bam_free(dbp, epg->page);
+		(void)__BT_TLPUT(dbp, epg->lock);
+	}
+	return (0);
+
+release:
+	/* Discard any remaining pages and return. */
+	for (; epg <= t->bt_csp; ++epg) {
+		(void)memp_fput(dbp->mpf, epg->page, 0);
+		(void)__BT_TLPUT(dbp, epg->lock);
+	}
+	return (ret);
+}