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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/lock/lock.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/lock/lock.c')
-rw-r--r--db2/lock/lock.c1362
1 files changed, 1362 insertions, 0 deletions
diff --git a/db2/lock/lock.c b/db2/lock/lock.c
new file mode 100644
index 0000000000..8fc91334a7
--- /dev/null
+++ b/db2/lock/lock.c
@@ -0,0 +1,1362 @@
+/*-
+ * See the file LICENSE for redistribution information.
+ *
+ * Copyright (c) 1996, 1997
+ *	Sleepycat Software.  All rights reserved.
+ */
+
+#include "config.h"
+
+#ifndef lint
+static const char sccsid[] = "@(#)lock.c	10.31 (Sleepycat) 8/17/97";
+#endif /* not lint */
+
+#ifndef NO_SYSTEM_INCLUDES
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#endif
+
+#include "db_int.h"
+#include "shqueue.h"
+#include "db_page.h"
+#include "db_shash.h"
+#include "lock.h"
+#include "common_ext.h"
+#include "db_am.h"
+
+static void __lock_checklocker __P((DB_LOCKTAB *, struct __db_lock *, int));
+static int  __lock_count_locks __P((DB_LOCKREGION *));
+static int  __lock_count_objs __P((DB_LOCKREGION *));
+static int  __lock_create __P((const char *, int, DB_ENV *));
+static void __lock_freeobj __P((DB_LOCKTAB *, DB_LOCKOBJ *));
+static int  __lock_get_internal __P((DB_LOCKTAB *, u_int32_t, int, const DBT *,
+    db_lockmode_t, struct __db_lock **));
+static int  __lock_grow_region __P((DB_LOCKTAB *, int, size_t));
+static int  __lock_put_internal __P((DB_LOCKTAB *, struct __db_lock *, int));
+static void __lock_remove_waiter
+    __P((DB_LOCKTAB *, DB_LOCKOBJ *, struct __db_lock *, db_status_t));
+static void __lock_reset_region __P((DB_LOCKTAB *));
+static int  __lock_validate_region __P((DB_LOCKTAB *));
+#ifdef DEBUG
+static void __lock_dump_locker __P((DB_LOCKTAB *, DB_LOCKOBJ *));
+static void __lock_dump_object __P((DB_LOCKTAB *, DB_LOCKOBJ *));
+static void __lock_printlock __P((DB_LOCKTAB *, struct __db_lock *, int));
+#endif
+
+/*
+ * Create and initialize a lock region in shared memory.
+ */
+
+/*
+ * __lock_create --
+ *	Create the lock region.  Returns an errno.  In most cases,
+ * the errno should be that returned by __db_ropen, in which case
+ * an EAGAIN means that we should retry, and an EEXIST means that
+ * the region exists and we didn't need to create it.  Any other
+ * sort of errno should be treated as a system error, leading to a
+ * failure of the original interface call.
+ */
+static int
+__lock_create(path, mode, dbenv)
+	const char *path;
+	int mode;
+	DB_ENV *dbenv;
+{
+	struct __db_lock *lp;
+	struct lock_header *tq_head;
+	struct obj_header *obj_head;
+	DB_LOCKOBJ *op;
+	DB_LOCKREGION *lrp;
+	u_int maxlocks;
+	u_int32_t i;
+	int fd, lock_modes, nelements, ret;
+	u_int8_t *conflicts, *curaddr;
+
+	maxlocks = dbenv == NULL || dbenv->lk_max == 0 ?
+	    DB_LOCK_DEFAULT_N : dbenv->lk_max;
+	lock_modes = dbenv == NULL || dbenv->lk_modes == 0 ?
+	    DB_LOCK_RW_N : dbenv->lk_modes;
+	conflicts = dbenv == NULL || dbenv->lk_conflicts == NULL ?
+	    (u_int8_t *)db_rw_conflicts : dbenv->lk_conflicts;
+
+	if ((ret =
+	    __db_rcreate(dbenv, DB_APP_NONE, path, DB_DEFAULT_LOCK_FILE, mode,
+	    LOCK_REGION_SIZE(lock_modes, maxlocks, __db_tablesize(maxlocks)),
+	    &fd, &lrp)) != 0)
+		return (ret);
+
+	/* Region exists; now initialize it. */
+	lrp->table_size = __db_tablesize(maxlocks);
+	lrp->magic = DB_LOCKMAGIC;
+	lrp->version = DB_LOCKVERSION;
+	lrp->id = 0;
+	lrp->maxlocks = maxlocks;
+	lrp->need_dd = 0;
+	lrp->detect = DB_LOCK_NORUN;
+	lrp->numobjs = maxlocks;
+	lrp->nlockers = 0;
+	lrp->mem_bytes = ALIGN(STRING_SIZE(maxlocks), sizeof(size_t));
+	lrp->increment = lrp->hdr.size / 2;
+	lrp->nmodes = lock_modes;
+	lrp->nconflicts = 0;
+	lrp->nrequests = 0;
+	lrp->nreleases = 0;
+	lrp->ndeadlocks = 0;
+
+	/*
+	 * As we write the region, we've got to maintain the alignment
+	 * for the structures that follow each chunk.  This information
+	 * ends up being encapsulated both in here as well as in the
+	 * lock.h file for the XXX_SIZE macros.
+	 */
+	/* Initialize conflict matrix. */
+	curaddr = (u_int8_t *)lrp + sizeof(DB_LOCKREGION);
+	memcpy(curaddr, conflicts, lock_modes * lock_modes);
+	curaddr += lock_modes * lock_modes;
+
+	/*
+	 * Initialize hash table.
+	 */
+	curaddr = (u_int8_t *)ALIGNP(curaddr, LOCK_HASH_ALIGN);
+	lrp->hash_off = curaddr - (u_int8_t *)lrp;
+	nelements = lrp->table_size;
+	__db_hashinit(curaddr, nelements);
+	curaddr += nelements * sizeof(DB_HASHTAB);
+
+	/*
+	 * Initialize locks onto a free list. Since locks contains mutexes,
+	 * we need to make sure that each lock is aligned on a MUTEX_ALIGNMENT
+	 * boundary.
+	 */
+	curaddr = (u_int8_t *)ALIGNP(curaddr, MUTEX_ALIGNMENT);
+	tq_head = &lrp->free_locks;
+	SH_TAILQ_INIT(tq_head);
+
+	for (i = 0; i++ < maxlocks;
+	    curaddr += ALIGN(sizeof(struct __db_lock), MUTEX_ALIGNMENT)) {
+		lp = (struct __db_lock *)curaddr;
+		lp->status = DB_LSTAT_FREE;
+		SH_TAILQ_INSERT_HEAD(tq_head, lp, links, __db_lock);
+	}
+
+	/* Initialize objects onto a free list.  */
+	obj_head = &lrp->free_objs;
+	SH_TAILQ_INIT(obj_head);
+
+	for (i = 0; i++ < maxlocks; curaddr += sizeof(DB_LOCKOBJ)) {
+		op = (DB_LOCKOBJ *)curaddr;
+		SH_TAILQ_INSERT_HEAD(obj_head, op, links, __db_lockobj);
+	}
+
+	/*
+	 * Initialize the string space; as for all shared memory allocation
+	 * regions, this requires size_t alignment, since we store the
+	 * lengths of malloc'd areas in the area..
+	 */
+	curaddr = (u_int8_t *)ALIGNP(curaddr, sizeof(size_t));
+	lrp->mem_off = curaddr - (u_int8_t *)lrp;
+	__db_shalloc_init(curaddr, lrp->mem_bytes);
+
+	/* Release the lock. */
+	(void)__db_mutex_unlock(&lrp->hdr.lock, fd);
+
+	/* Now unmap the region. */
+	if ((ret = __db_rclose(dbenv, fd, lrp)) != 0) {
+		(void)lock_unlink(path, 1 /* force */, dbenv);
+		return (ret);
+	}
+
+	return (0);
+}
+
+int
+lock_open(path, flags, mode, dbenv, ltp)
+	const char *path;
+	int flags, mode;
+	DB_ENV *dbenv;
+	DB_LOCKTAB **ltp;
+{
+	DB_LOCKTAB *lt;
+	int ret, retry_cnt;
+
+	/* Validate arguments. */
+#ifdef HAVE_SPINLOCKS
+#define	OKFLAGS	(DB_CREATE | DB_THREAD)
+#else
+#define	OKFLAGS	(DB_CREATE)
+#endif
+	if ((ret = __db_fchk(dbenv, "lock_open", flags, OKFLAGS)) != 0)
+		return (ret);
+
+	/*
+	 * Create the lock table structure.
+	 */
+	if ((lt = (DB_LOCKTAB *)calloc(1, sizeof(DB_LOCKTAB))) == NULL) {
+		__db_err(dbenv, "%s", strerror(errno));
+		return (ENOMEM);
+	}
+	lt->dbenv = dbenv;
+
+	/*
+	 * Now, create the lock region if it doesn't already exist.
+	 */
+	retry_cnt = 0;
+retry:	if (LF_ISSET(DB_CREATE) &&
+	    (ret = __lock_create(path, mode, dbenv)) != 0)
+		if (ret == EAGAIN && ++retry_cnt < 3) {
+			(void)__db_sleep(1, 0);
+			goto retry;
+		} else if (ret == EEXIST) /* We did not create the region */
+			LF_CLR(DB_CREATE);
+		else
+			goto out;
+
+	/*
+	 * Finally, open the region, map it in, and increment the
+	 * reference count.
+	 */
+	retry_cnt = 0;
+retry1:	if ((ret = __db_ropen(dbenv, DB_APP_NONE, path, DB_DEFAULT_LOCK_FILE,
+	    LF_ISSET(~(DB_CREATE | DB_THREAD)), &lt->fd, &lt->region)) != 0) {
+		if (ret == EAGAIN && ++retry_cnt < 3) {
+			(void)__db_sleep(1, 0);
+			goto retry1;
+		}
+		goto out;
+	 }
+
+	if (lt->region->magic != DB_LOCKMAGIC) {
+		__db_err(dbenv, "lock_open: Bad magic number");
+		ret = EINVAL;
+		goto out;
+	}
+
+	/* Check for automatic deadlock detection. */
+	if (dbenv->lk_detect != DB_LOCK_NORUN) {
+		if (lt->region->detect != DB_LOCK_NORUN &&
+		    dbenv->lk_detect != DB_LOCK_DEFAULT &&
+		    lt->region->detect != dbenv->lk_detect) {
+			__db_err(dbenv,
+			    "lock_open: incompatible deadlock detector mode");
+			ret = EINVAL;
+			goto out;
+		}
+		if (lt->region->detect == DB_LOCK_NORUN)
+			lt->region->detect = dbenv->lk_detect;
+	}
+
+	/* Set up remaining pointers into region. */
+	lt->conflicts = (u_int8_t *)lt->region + sizeof(DB_LOCKREGION);
+	lt->hashtab =
+	    (DB_HASHTAB *)((u_int8_t *)lt->region + lt->region->hash_off);
+	lt->mem = (void *)((u_int8_t *)lt->region + lt->region->mem_off);
+	lt->reg_size = lt->region->hdr.size;
+
+	*ltp = lt;
+	return (0);
+
+/* Error handling. */
+out:	if (lt->region != NULL)
+		(void)__db_rclose(lt->dbenv, lt->fd, lt->region);
+	if (LF_ISSET(DB_CREATE))
+		(void)lock_unlink(path, 1, lt->dbenv);
+	free(lt);
+	return (ret);
+}
+
+int
+lock_id (lt, idp)
+	DB_LOCKTAB *lt;
+	u_int32_t *idp;
+{
+	u_int32_t id;
+
+	LOCK_LOCKREGION(lt);
+	if (lt->region->id >= DB_LOCK_MAXID)
+		lt->region->id = 0;
+	id = ++lt->region->id;
+	UNLOCK_LOCKREGION(lt);
+
+	*idp = id;
+	return (0);
+}
+
+int
+lock_vec(lt, locker, flags, list, nlist, elistp)
+	DB_LOCKTAB *lt;
+	u_int32_t locker;
+	int flags, nlist;
+	DB_LOCKREQ *list, **elistp;
+{
+	struct __db_lock *lp;
+	DB_LOCKOBJ *sh_obj, *sh_locker;
+	int i, ret, run_dd;
+
+	/* Validate arguments. */
+	if ((ret =
+	    __db_fchk(lt->dbenv, "lock_vec", flags, DB_LOCK_NOWAIT)) != 0)
+		return (ret);
+
+	LOCK_LOCKREGION(lt);
+
+	if ((ret = __lock_validate_region(lt)) != 0) {
+		UNLOCK_LOCKREGION(lt);
+		return (ret);
+	}
+
+	ret = 0;
+	for (i = 0; i < nlist && ret == 0; i++) {
+		switch (list[i].op) {
+		case DB_LOCK_GET:
+			ret = __lock_get_internal(lt, locker, flags,
+			    list[i].obj, list[i].mode, &lp);
+			if (ret == 0)
+				list[i].lock = LOCK_TO_OFFSET(lt, lp);
+			break;
+		case DB_LOCK_PUT:
+			lp = OFFSET_TO_LOCK(lt, list[i].lock);
+			if (lp->holder != locker) {
+				ret = DB_LOCK_NOTHELD;
+				break;
+			}
+			list[i].mode = lp->mode;
+
+			/* XXX Need to copy the object. ??? */
+			ret = __lock_put_internal(lt, lp, 0);
+			break;
+		case DB_LOCK_PUT_ALL:
+			/* Find the locker. */
+			if ((ret = __lock_getobj(lt, locker,
+			    NULL, DB_LOCK_LOCKER, &sh_locker)) != 0)
+				break;
+
+			for (lp = SH_LIST_FIRST(&sh_locker->heldby, __db_lock);
+			    lp != NULL;
+			    lp = SH_LIST_FIRST(&sh_locker->heldby, __db_lock)) {
+				if ((ret = __lock_put_internal(lt, lp, 0)) != 0)
+					break;
+			}
+			__lock_freeobj(lt, sh_locker);
+			lt->region->nlockers--;
+			break;
+		case DB_LOCK_PUT_OBJ:
+
+			/* Look up the object in the hash table. */
+			__db_hashlookup(lt->hashtab, __db_lockobj, links,
+			    list[i].obj, sh_obj, lt->region->table_size,
+			    __lock_ohash, __lock_cmp);
+			if (sh_obj == NULL) {
+				ret = EINVAL;
+				break;
+			}
+			/*
+			 * Release waiters first, because they won't cause
+			 * anyone else to be awakened.  If we release the
+			 * lockers first, all the waiters get awakened
+			 * needlessly.
+			 */
+			for (lp = SH_TAILQ_FIRST(&sh_obj->waiters, __db_lock);
+			    lp != NULL;
+			    lp = SH_TAILQ_FIRST(&sh_obj->waiters, __db_lock)) {
+				lt->region->nreleases += lp->refcount;
+				__lock_remove_waiter(lt, sh_obj, lp,
+				    DB_LSTAT_NOGRANT);
+				__lock_checklocker(lt, lp, 1);
+			}
+
+			for (lp = SH_TAILQ_FIRST(&sh_obj->holders, __db_lock);
+			    lp != NULL;
+			    lp = SH_TAILQ_FIRST(&sh_obj->holders, __db_lock)) {
+
+				lt->region->nreleases += lp->refcount;
+				SH_LIST_REMOVE(lp, locker_links, __db_lock);
+				SH_TAILQ_REMOVE(&sh_obj->holders, lp, links,
+				    __db_lock);
+				lp->status = DB_LSTAT_FREE;
+				SH_TAILQ_INSERT_HEAD(&lt->region->free_locks,
+				    lp, links, __db_lock);
+			}
+
+			/* Now free the object. */
+			__lock_freeobj(lt, sh_obj);
+			break;
+#ifdef DEBUG
+		case DB_LOCK_DUMP:
+			/* Find the locker. */
+			if ((ret = __lock_getobj(lt, locker,
+			    NULL, DB_LOCK_LOCKER, &sh_locker)) != 0)
+				break;
+
+			for (lp = SH_LIST_FIRST(&sh_locker->heldby, __db_lock);
+			    lp != NULL;
+			    lp = SH_LIST_NEXT(lp, locker_links, __db_lock)) {
+				__lock_printlock(lt, lp, 1);
+				ret = EINVAL;
+			}
+			if (ret == 0) {
+				__lock_freeobj(lt, sh_locker);
+				lt->region->nlockers--;
+			}
+			break;
+#endif
+		default:
+			ret = EINVAL;
+			break;
+		}
+	}
+
+	if (lt->region->need_dd && lt->region->detect != DB_LOCK_NORUN) {
+		run_dd = 1;
+		lt->region->need_dd = 0;
+	} else
+		run_dd = 0;
+
+	UNLOCK_LOCKREGION(lt);
+
+	if (ret == 0 && run_dd)
+		lock_detect(lt, 0, lt->region->detect);
+
+	if (elistp && ret != 0)
+		*elistp = &list[i - 1];
+	return (ret);
+}
+
+int
+lock_get(lt, locker, flags, obj, lock_mode, lock)
+	DB_LOCKTAB *lt;
+	u_int32_t locker;
+	int flags;
+	const DBT *obj;
+	db_lockmode_t lock_mode;
+	DB_LOCK *lock;
+{
+	struct __db_lock *lockp;
+	int ret;
+
+	/* Validate arguments. */
+	if ((ret =
+	    __db_fchk(lt->dbenv, "lock_get", flags, DB_LOCK_NOWAIT)) != 0)
+		return (ret);
+
+	LOCK_LOCKREGION(lt);
+
+	ret = __lock_validate_region(lt);
+	if (ret == 0 && (ret = __lock_get_internal(lt,
+	    locker, flags, obj, lock_mode, &lockp)) == 0) {
+		*lock = LOCK_TO_OFFSET(lt, lockp);
+		lt->region->nrequests++;
+	}
+
+	UNLOCK_LOCKREGION(lt);
+	return (ret);
+}
+
+int
+lock_put(lt, lock)
+	DB_LOCKTAB *lt;
+	DB_LOCK lock;
+{
+	struct __db_lock *lockp;
+	int ret, run_dd;
+
+	LOCK_LOCKREGION(lt);
+
+	if ((ret = __lock_validate_region(lt)) != 0)
+		return (ret);
+	else {
+		lockp = OFFSET_TO_LOCK(lt, lock);
+		ret = __lock_put_internal(lt, lockp, 0);
+	}
+
+	__lock_checklocker(lt, lockp, 0);
+
+	if (lt->region->need_dd && lt->region->detect != DB_LOCK_NORUN) {
+		run_dd = 1;
+		lt->region->need_dd = 0;
+	} else
+		run_dd = 0;
+
+	UNLOCK_LOCKREGION(lt);
+
+	if (ret == 0 && run_dd)
+		lock_detect(lt, 0, lt->region->detect);
+
+	return (ret);
+}
+
+int
+lock_close(lt)
+	DB_LOCKTAB *lt;
+{
+	int ret;
+
+	if ((ret = __db_rclose(lt->dbenv, lt->fd, lt->region)) != 0)
+		return (ret);
+
+	/* Free lock table. */
+	free(lt);
+	return (0);
+}
+
+int
+lock_unlink(path, force, dbenv)
+	const char *path;
+	int force;
+	DB_ENV *dbenv;
+{
+	return (__db_runlink(dbenv,
+	    DB_APP_NONE, path, DB_DEFAULT_LOCK_FILE, force));
+}
+
+/*
+ * XXX This looks like it could be void, but I'm leaving it returning
+ * an int because I think it will have to when we go through and add
+ * the appropriate error checking for the EINTR on mutexes.
+ */
+static int
+__lock_put_internal(lt, lockp, do_all)
+	DB_LOCKTAB *lt;
+	struct __db_lock *lockp;
+	int do_all;
+{
+	struct __db_lock *lp_w, *lp_h, *next_waiter;
+	DB_LOCKOBJ *sh_obj;
+	int state_changed;
+
+	if (lockp->refcount == 0 || (lockp->status != DB_LSTAT_HELD &&
+	    lockp->status != DB_LSTAT_WAITING) || lockp->obj == 0) {
+		__db_err(lt->dbenv, "lock_put: invalid lock %lu",
+		    (u_long)((u_int8_t *)lockp - (u_int8_t *)lt->region));
+		return (EINVAL);
+	}
+
+	if (do_all)
+		lt->region->nreleases += lockp->refcount;
+	else
+		lt->region->nreleases++;
+	if (do_all == 0 && lockp->refcount > 1) {
+		lockp->refcount--;
+		return (0);
+	}
+
+	/* Get the object associated with this lock. */
+	sh_obj = (DB_LOCKOBJ *)((u_int8_t *)lockp + lockp->obj);
+
+	/* Remove lock from locker list. */
+	SH_LIST_REMOVE(lockp, locker_links, __db_lock);
+
+	/* Remove this lock from its holders/waitlist. */
+	if (lockp->status != DB_LSTAT_HELD)
+		__lock_remove_waiter(lt, sh_obj, lockp, DB_LSTAT_FREE);
+	else
+		SH_TAILQ_REMOVE(&sh_obj->holders, lockp, links, __db_lock);
+
+	/*
+	 * We need to do lock promotion.  We also need to determine if
+	 * we're going to need to run the deadlock detector again.  If
+	 * we release locks, and there are waiters, but no one gets promoted,
+	 * then we haven't fundamentally changed the lockmgr state, so
+	 * we may still have a deadlock and we have to run again.  However,
+	 * if there were no waiters, or we actually promoted someone, then
+	 * we are OK and we don't have to run it immediately.
+	 */
+	for (lp_w = SH_TAILQ_FIRST(&sh_obj->waiters, __db_lock),
+	    state_changed = lp_w == NULL;
+	    lp_w != NULL;
+	    lp_w = next_waiter) {
+		next_waiter = SH_TAILQ_NEXT(lp_w, links, __db_lock);
+		for (lp_h = SH_TAILQ_FIRST(&sh_obj->holders, __db_lock);
+		    lp_h != NULL;
+		    lp_h = SH_TAILQ_NEXT(lp_h, links, __db_lock)) {
+			if (CONFLICTS(lt, lp_h->mode, lp_w->mode) &&
+			    lp_h->holder != lp_w->holder)
+				break;
+		}
+		if (lp_h != NULL)	/* Found a conflict. */
+			break;
+
+		/* No conflict, promote the waiting lock. */
+		SH_TAILQ_REMOVE(&sh_obj->waiters, lp_w, links, __db_lock);
+		lp_w->status = DB_LSTAT_PENDING;
+		SH_TAILQ_INSERT_TAIL(&sh_obj->holders, lp_w, links);
+
+		/* Wake up waiter. */
+		(void)__db_mutex_unlock(&lp_w->mutex, lt->fd);
+		state_changed = 1;
+	}
+
+	/* Check if object should be reclaimed. */
+	if (SH_TAILQ_FIRST(&sh_obj->holders, __db_lock) == NULL) {
+		__db_hashremove_el(lt->hashtab, __db_lockobj, links, sh_obj,
+		    lt->region->table_size, __lock_lhash);
+		__db_shalloc_free(lt->mem, SH_DBT_PTR(&sh_obj->lockobj));
+		SH_TAILQ_INSERT_HEAD(&lt->region->free_objs, sh_obj, links,
+		    __db_lockobj);
+		state_changed = 1;
+	}
+
+	/* Free lock. */
+	lockp->status = DB_LSTAT_FREE;
+	SH_TAILQ_INSERT_HEAD(&lt->region->free_locks, lockp, links, __db_lock);
+
+	/*
+	 * If we did not promote anyone; we need to run the deadlock
+	 * detector again.
+	 */
+	if (state_changed == 0)
+		lt->region->need_dd = 1;
+
+	return (0);
+}
+
+static int
+__lock_get_internal(lt, locker, flags, obj, lock_mode, lockp)
+	DB_LOCKTAB *lt;
+	u_int32_t locker;
+	int flags;
+	const DBT *obj;
+	db_lockmode_t lock_mode;
+	struct __db_lock **lockp;
+{
+	struct __db_lock *newl, *lp;
+	DB_LOCKOBJ *sh_obj, *sh_locker;
+	DB_LOCKREGION *lrp;
+	size_t newl_off;
+	int ret;
+
+	ret = 0;
+	/*
+	 * Check that lock mode is valid.
+	 */
+
+	lrp = lt->region;
+	if ((u_int32_t)lock_mode >= lrp->nmodes) {
+		__db_err(lt->dbenv,
+		    "lock_get: invalid lock mode %lu\n", (u_long)lock_mode);
+		return (EINVAL);
+	}
+
+	/* Allocate a new lock.  Optimize for the common case of a grant. */
+	if ((newl = SH_TAILQ_FIRST(&lrp->free_locks, __db_lock)) == NULL) {
+		if ((ret = __lock_grow_region(lt, DB_LOCK_LOCK, 0)) != 0)
+			return (ret);
+		lrp = lt->region;
+		newl = SH_TAILQ_FIRST(&lrp->free_locks, __db_lock);
+	}
+	newl_off = LOCK_TO_OFFSET(lt, newl);
+
+	/* Optimize for common case of granting a lock. */
+	SH_TAILQ_REMOVE(&lrp->free_locks, newl, links, __db_lock);
+
+	newl->mode = lock_mode;
+	newl->status = DB_LSTAT_HELD;
+	newl->holder = locker;
+	newl->refcount = 1;
+
+	if ((ret =
+	    __lock_getobj(lt, 0, (DBT *)obj, DB_LOCK_OBJTYPE, &sh_obj)) != 0)
+		return (ret);
+
+	lrp = lt->region;			/* getobj might have grown */
+	newl = OFFSET_TO_LOCK(lt, newl_off);
+
+	/* Now make new lock point to object */
+	newl->obj = SH_PTR_TO_OFF(newl, sh_obj);
+
+	/*
+	 * Now we have a lock and an object and we need to see if we should
+	 * grant the lock.  We use a FIFO ordering so we can only grant a
+	 * new lock if it does not conflict with anyone on the holders list
+	 * OR anyone on the waiters list.  In case of conflict, we put the
+	 * new lock on the end of the waiters list.
+	 */
+	for (lp = SH_TAILQ_FIRST(&sh_obj->holders, __db_lock);
+	    lp != NULL;
+	    lp = SH_TAILQ_NEXT(lp, links, __db_lock)) {
+		if (CONFLICTS(lt, lp->mode, lock_mode) &&
+		    locker != lp->holder)
+			break;
+		else if (lp->holder == locker && lp->mode == lock_mode &&
+		    lp->status == DB_LSTAT_HELD) {
+			/* Lock is already held, just inc the ref count. */
+			lp->refcount++;
+			SH_TAILQ_INSERT_HEAD(&lrp->free_locks, newl, links,
+			    __db_lock);
+			*lockp = lp;
+			return (0);
+		}
+    	}
+
+	if (lp == NULL)
+		for (lp = SH_TAILQ_FIRST(&sh_obj->waiters, __db_lock);
+		    lp != NULL;
+		    lp = SH_TAILQ_NEXT(lp, links, __db_lock)) {
+			if (CONFLICTS(lt, lp->mode, lock_mode) &&
+			    locker != lp->holder)
+				break;
+		}
+	if (lp == NULL)
+		SH_TAILQ_INSERT_TAIL(&sh_obj->holders, newl, links);
+	else if (!(flags & DB_LOCK_NOWAIT))
+		SH_TAILQ_INSERT_TAIL(&sh_obj->waiters, newl, links);
+	else {
+		/* Free the lock and return an error. */
+		newl->status = DB_LSTAT_FREE;
+		SH_TAILQ_INSERT_HEAD(&lrp->free_locks, newl, links, __db_lock);
+		return (DB_LOCK_NOTGRANTED);
+	}
+
+	/*
+	 * This is really a blocker for the process, so initialize it
+	 * set.  That way the current process will block when it tries
+	 * to get it and the waking process will release it.
+	 */
+	(void)__db_mutex_init(&newl->mutex,
+	    MUTEX_LOCK_OFFSET(lt->region, &newl->mutex));
+	(void)__db_mutex_lock(&newl->mutex, lt->fd,
+	    lt->dbenv == NULL ? NULL : lt->dbenv->db_yield);
+
+	/*
+	 * Now, insert the lock onto its locker's list.
+	 */
+	if ((ret =
+	    __lock_getobj(lt, locker, NULL, DB_LOCK_LOCKER, &sh_locker)) != 0)
+		return (ret);
+
+	lrp = lt->region;
+	SH_LIST_INSERT_HEAD(&sh_locker->heldby, newl, locker_links, __db_lock);
+
+	if (lp != NULL) {
+		newl->status = DB_LSTAT_WAITING;
+		lrp->nconflicts++;
+		/*
+		 * We are about to wait; must release the region mutex.
+		 * Then, when we wakeup, we need to reacquire the region
+		 * mutex before continuing.
+		 */
+		if (lrp->detect == DB_LOCK_NORUN)
+			lt->region->need_dd = 1;
+		UNLOCK_LOCKREGION(lt);
+
+		/*
+		 * We are about to wait; before waiting, see if the deadlock
+		 * detector should be run.
+		 */
+		if (lrp->detect != DB_LOCK_NORUN)
+			ret = lock_detect(lt, 0, lrp->detect);
+
+		(void)__db_mutex_lock(&newl->mutex,
+		    lt->fd, lt->dbenv == NULL ? NULL : lt->dbenv->db_yield);
+
+		LOCK_LOCKREGION(lt);
+		if (newl->status != DB_LSTAT_PENDING) {
+			/* Return to free list. */
+			__lock_checklocker(lt, newl, 0);
+			SH_TAILQ_INSERT_HEAD(&lrp->free_locks, newl, links,
+			    __db_lock);
+			switch (newl->status) {
+				case DB_LSTAT_ABORTED:
+					ret = DB_LOCK_DEADLOCK;
+					break;
+				case DB_LSTAT_NOGRANT:
+					ret = DB_LOCK_NOTGRANTED;
+					break;
+				default:
+					ret = EINVAL;
+					break;
+			}
+			newl->status = DB_LSTAT_FREE;
+			newl = NULL;
+		} else
+			newl->status = DB_LSTAT_HELD;
+	}
+
+	*lockp = newl;
+	return (ret);
+}
+
+/*
+ * This is called at every interface to verify if the region
+ * has changed size, and if so, to remap the region in and
+ * reset the process pointers.
+ */
+static int
+__lock_validate_region(lt)
+	DB_LOCKTAB *lt;
+{
+	int ret;
+
+	if (lt->reg_size == lt->region->hdr.size)
+		return (0);
+
+	/* Grow the region. */
+	if ((ret = __db_rremap(lt->dbenv, lt->region,
+	    lt->reg_size, lt->region->hdr.size, lt->fd, &lt->region)) != 0)
+		return (ret);
+
+	__lock_reset_region(lt);
+
+	return (0);
+}
+
+/*
+ * We have run out of space; time to grow the region.
+ */
+static int
+__lock_grow_region(lt, which, howmuch)
+	DB_LOCKTAB *lt;
+	int which;
+	size_t howmuch;
+{
+	struct __db_lock *newl;
+	struct lock_header *lock_head;
+	struct obj_header *obj_head;
+	DB_LOCKOBJ *op;
+	DB_LOCKREGION *lrp;
+	float lock_ratio, obj_ratio;
+	size_t incr, oldsize, used;
+	u_int32_t i, newlocks, newmem, newobjs;
+	int ret, usedlocks, usedmem, usedobjs;
+	u_int8_t *curaddr;
+
+	lrp = lt->region;
+	oldsize = lrp->hdr.size;
+	incr = lrp->increment;
+
+	/* Figure out how much of each sort of space we have. */
+	usedmem = lrp->mem_bytes - __db_shalloc_count(lt->mem);
+	usedobjs = lrp->numobjs - __lock_count_objs(lrp);
+	usedlocks = lrp->maxlocks - __lock_count_locks(lrp);
+
+	/*
+	 * Figure out what fraction of the used space belongs to each
+	 * different type of "thing" in the region.  Then partition the
+	 * new space up according to this ratio.
+	 */
+	used = usedmem +
+	    usedlocks * ALIGN(sizeof(struct __db_lock), MUTEX_ALIGNMENT) +
+	    usedobjs * sizeof(DB_LOCKOBJ);
+
+	lock_ratio = usedlocks *
+	    ALIGN(sizeof(struct __db_lock), MUTEX_ALIGNMENT) / (float)used;
+	obj_ratio = usedobjs * sizeof(DB_LOCKOBJ) / (float)used;
+
+	newlocks = (u_int32_t)(lock_ratio *
+	    incr / ALIGN(sizeof(struct __db_lock), MUTEX_ALIGNMENT));
+	newobjs = (u_int32_t)(obj_ratio * incr / sizeof(DB_LOCKOBJ));
+	newmem = incr -
+	    (newobjs * sizeof(DB_LOCKOBJ) +
+	    newlocks * ALIGN(sizeof(struct __db_lock), MUTEX_ALIGNMENT));
+
+	/*
+	 * Make sure we allocate enough memory for the object being
+	 * requested.
+	 */
+	switch (which) {
+		case DB_LOCK_LOCK:
+			if (newlocks == 0) {
+				newlocks = 10;
+				incr += newlocks * sizeof(struct __db_lock);
+			}
+			break;
+		case DB_LOCK_OBJ:
+			if (newobjs == 0) {
+				newobjs = 10;
+				incr += newobjs * sizeof(DB_LOCKOBJ);
+			}
+			break;
+		case DB_LOCK_MEM:
+			if (newmem < howmuch * 2) {
+				incr += howmuch * 2 - newmem;
+				newmem = howmuch * 2;
+			}
+			break;
+	}
+
+	newmem += ALIGN(incr, sizeof(size_t)) - incr;
+	incr = ALIGN(incr, sizeof(size_t));
+
+	/*
+	 * Since we are going to be allocating locks at the beginning of the
+	 * new chunk, we need to make sure that the chunk is MUTEX_ALIGNMENT
+	 * aligned.  We did not guarantee this when we created the region, so
+	 * we may need to pad the old region by extra bytes to ensure this
+	 * alignment.
+	 */
+	incr += ALIGN(oldsize, MUTEX_ALIGNMENT) - oldsize;
+
+	__db_err(lt->dbenv,
+	    "Growing lock region: %lu locks %lu objs %lu bytes",
+	    (u_long)newlocks, (u_long)newobjs, (u_long)newmem);
+
+	if ((ret = __db_rgrow(lt->dbenv, lt->fd, incr)) != 0)
+		return (ret);
+	if ((ret = __db_rremap(lt->dbenv,
+	    lt->region, oldsize, oldsize + incr, lt->fd, &lt->region)) != 0)
+		return (ret);
+	__lock_reset_region(lt);
+
+	/* Update region parameters. */
+	lrp = lt->region;
+	lrp->increment = incr << 1;
+	lrp->maxlocks += newlocks;
+	lrp->numobjs += newobjs;
+	lrp->mem_bytes += newmem;
+
+	curaddr = (u_int8_t *)lrp + oldsize;
+	curaddr = (u_int8_t *)ALIGNP(curaddr, MUTEX_ALIGNMENT);
+
+	/* Put new locks onto the free list. */
+	lock_head = &lrp->free_locks;
+	for (i = 0; i++ < newlocks;
+	    curaddr += ALIGN(sizeof(struct __db_lock), MUTEX_ALIGNMENT)) {
+		newl = (struct __db_lock *)curaddr;
+		SH_TAILQ_INSERT_HEAD(lock_head, newl, links, __db_lock);
+	}
+
+	/* Put new objects onto the free list.  */
+	obj_head = &lrp->free_objs;
+	for (i = 0; i++ < newobjs; curaddr += sizeof(DB_LOCKOBJ)) {
+		op = (DB_LOCKOBJ *)curaddr;
+		SH_TAILQ_INSERT_HEAD(obj_head, op, links, __db_lockobj);
+	}
+
+	*((size_t *)curaddr) = newmem - sizeof(size_t);
+	curaddr += sizeof(size_t);
+	__db_shalloc_free(lt->mem, curaddr);
+
+	return (0);
+}
+
+#ifdef DEBUG
+void
+__lock_dump_region(lt, flags)
+	DB_LOCKTAB *lt;
+	unsigned long flags;
+{
+	struct __db_lock *lp;
+	DB_LOCKOBJ *op;
+	DB_LOCKREGION *lrp;
+	u_int32_t i, j;
+
+	lrp = lt->region;
+
+	printf("Lock region parameters\n");
+	printf("%s:0x%x\t%s:%lu\t%s:%lu\t%s:%lu\n%s:%lu\t%s:%lu\t%s:%lu\t\n",
+	    "magic      ", lrp->magic,
+	    "version    ", (u_long)lrp->version,
+	    "processes  ", (u_long)lrp->hdr.refcnt,
+	    "maxlocks   ", (u_long)lrp->maxlocks,
+	    "table size ", (u_long)lrp->table_size,
+	    "nmodes     ", (u_long)lrp->nmodes,
+	    "numobjs    ", (u_long)lrp->numobjs);
+	printf("%s:%lu\t%s:%lu\t%s:%lu\n%s:%lu\t%s:%lu\t%s:%lu\n",
+	    "size       ", (u_long)lrp->hdr.size,
+	    "nlockers   ", (u_long)lrp->nlockers,
+	    "hash_off   ", (u_long)lrp->hash_off,
+	    "increment  ", (u_long)lrp->increment,
+	    "mem_off    ", (u_long)lrp->mem_off,
+	    "mem_bytes  ", (u_long)lrp->mem_bytes);
+#ifndef HAVE_SPINLOCKS
+	printf("Mutex: off %lu", (u_long)lrp->hdr.lock.off);
+#endif
+#ifdef MUTEX_STATISTICS
+	printf(" waits %lu nowaits %lu",
+	    (u_long)lrp->hdr.lock.mutex_set_wait,
+	    (u_long)lrp->hdr.lock.mutex_set_nowait);
+#endif
+	printf("\n%s:%lu\t%s:%lu\t%s:%lu\t%s:%lu\n",
+	    "nconflicts ", (u_long)lrp->nconflicts,
+	    "nrequests  ", (u_long)lrp->nrequests,
+	    "nreleases  ", (u_long)lrp->nreleases,
+	    "ndeadlocks ", (u_long)lrp->ndeadlocks);
+	printf("need_dd    %lu\n", (u_long)lrp->need_dd);
+	if (flags & LOCK_DEBUG_CONF) {
+		printf("\nConflict matrix\n");
+
+		for (i = 0; i < lrp->nmodes; i++) {
+			for (j = 0; j < lrp->nmodes; j++)
+				printf("%lu\t",
+				    (u_long)lt->conflicts[i * lrp->nmodes + j]);
+			printf("\n");
+		}
+	}
+
+	for (i = 0; i < lrp->table_size; i++) {
+		op = SH_TAILQ_FIRST(&lt->hashtab[i], __db_lockobj);
+		if (op != NULL && flags & LOCK_DEBUG_BUCKET)
+			printf("Bucket %lu:\n", (unsigned long)i);
+		while (op != NULL) {
+			if (op->type == DB_LOCK_LOCKER &&
+			    flags & LOCK_DEBUG_LOCKERS)
+				__lock_dump_locker(lt, op);
+			else if (flags & LOCK_DEBUG_OBJECTS &&
+			    op->type == DB_LOCK_OBJTYPE)
+				__lock_dump_object(lt, op);
+			op = SH_TAILQ_NEXT(op, links, __db_lockobj);
+		}
+	}
+
+	if (flags & LOCK_DEBUG_LOCK) {
+		printf("\nLock Free List\n");
+		for (lp = SH_TAILQ_FIRST(&lrp->free_locks, __db_lock);
+		    lp != NULL;
+		    lp = SH_TAILQ_NEXT(lp, links, __db_lock)) {
+			printf("0x%x: %lu\t%lu\t%lu\t0x%x\n", (u_int)lp,
+			    (u_long)lp->holder, (u_long)lp->mode,
+			    (u_long)lp->status, (u_int)lp->obj);
+		}
+	}
+
+	if (flags & LOCK_DEBUG_LOCK) {
+		printf("\nObject Free List\n");
+		for (op = SH_TAILQ_FIRST(&lrp->free_objs, __db_lockobj);
+		    op != NULL;
+		    op = SH_TAILQ_NEXT(op, links, __db_lockobj))
+			printf("0x%x\n", (u_int)op);
+	}
+
+	if (flags & LOCK_DEBUG_MEM) {
+		printf("\nMemory Free List\n");
+		__db_shalloc_dump(stdout, lt->mem);
+	}
+}
+
+static void
+__lock_dump_locker(lt, op)
+	DB_LOCKTAB *lt;
+	DB_LOCKOBJ *op;
+{
+	struct __db_lock *lp;
+	u_int32_t locker;
+	void *ptr;
+
+	ptr = SH_DBT_PTR(&op->lockobj);
+	memcpy(&locker, ptr, sizeof(u_int32_t));
+	printf("L %lu", (u_long)locker);
+
+	lp = SH_LIST_FIRST(&op->heldby, __db_lock);
+	if (lp == NULL) {
+		printf("\n");
+		return;
+	}
+	for (; lp != NULL; lp = SH_LIST_NEXT(lp, locker_links, __db_lock))
+		__lock_printlock(lt, lp, 0);
+}
+
+static void
+__lock_dump_object(lt, op)
+	DB_LOCKTAB *lt;
+	DB_LOCKOBJ *op;
+{
+	struct __db_lock *lp;
+	u_int32_t j;
+	char *ptr;
+
+	ptr = SH_DBT_PTR(&op->lockobj);
+	for (j = 0; j < op->lockobj.size; ptr++, j++)
+		printf("%c", (int)*ptr);
+	printf("\n");
+
+	printf("H:");
+	for (lp =
+	    SH_TAILQ_FIRST(&op->holders, __db_lock);
+	    lp != NULL;
+	    lp = SH_TAILQ_NEXT(lp, links, __db_lock))
+		__lock_printlock(lt, lp, 0);
+	lp = SH_TAILQ_FIRST(&op->waiters, __db_lock);
+	if (lp != NULL) {
+		printf("\nW:");
+		for (; lp != NULL; lp = SH_TAILQ_NEXT(lp, links, __db_lock))
+			__lock_printlock(lt, lp, 0);
+	}
+}
+
+int
+__lock_is_locked(lt, locker, dbt, mode)
+	DB_LOCKTAB *lt;
+	u_int32_t locker;
+	DBT *dbt;
+	db_lockmode_t mode;
+{
+	struct __db_lock *lp;
+	DB_LOCKOBJ *sh_obj;
+	DB_LOCKREGION *lrp;
+
+	lrp = lt->region;
+
+	/* Look up the object in the hash table. */
+	__db_hashlookup(lt->hashtab, __db_lockobj, links,
+	    dbt, sh_obj, lrp->table_size, __lock_ohash, __lock_cmp);
+	if (sh_obj == NULL)
+		return (0);
+
+	for (lp = SH_TAILQ_FIRST(&sh_obj->holders, __db_lock);
+	    lp != NULL;
+	    lp = SH_TAILQ_FIRST(&sh_obj->holders, __db_lock)) {
+		if (lp->holder == locker && lp->mode == mode)
+			return (1);
+	}
+
+	return (0);
+}
+
+static void
+__lock_printlock(lt, lp, ispgno)
+	DB_LOCKTAB *lt;
+	struct __db_lock *lp;
+	int ispgno;
+{
+	DB_LOCKOBJ *lockobj;
+	db_pgno_t pgno;
+	size_t obj;
+	u_int8_t *ptr;
+	char *mode, *stat;
+
+	switch (lp->mode) {
+	case DB_LOCK_IREAD:
+		mode = "IREAD";
+		break;
+	case DB_LOCK_IWR:
+		mode = "IWR";
+		break;
+	case DB_LOCK_IWRITE:
+		mode = "IWRITE";
+		break;
+	case DB_LOCK_NG:
+		mode = "NG";
+		break;
+	case DB_LOCK_READ:
+		mode = "READ";
+		break;
+	case DB_LOCK_WRITE:
+		mode = "WRITE";
+		break;
+	default:
+		mode = "UNKNOWN";
+		break;
+	}
+	switch (lp->status) {
+	case DB_LSTAT_ABORTED:
+		stat = "ABORT";
+		break;
+	case DB_LSTAT_ERR:
+		stat = "ERROR";
+		break;
+	case DB_LSTAT_FREE:
+		stat = "FREE";
+		break;
+	case DB_LSTAT_HELD:
+		stat = "HELD";
+		break;
+	case DB_LSTAT_NOGRANT:
+		stat = "NONE";
+		break;
+	case DB_LSTAT_WAITING:
+		stat = "WAIT";
+		break;
+	case DB_LSTAT_PENDING:
+		stat = "PENDING";
+		break;
+	default:
+		stat = "UNKNOWN";
+		break;
+	}
+	printf("\t%lu\t%s\t%lu\t%s\t",
+	    (u_long)lp->holder, mode, (u_long)lp->refcount, stat);
+
+	lockobj = (DB_LOCKOBJ *)((u_int8_t *)lp + lp->obj);
+	ptr = SH_DBT_PTR(&lockobj->lockobj);
+	if (ispgno) {
+		/* Assume this is a DBT lock. */
+		memcpy(&pgno, ptr, sizeof(db_pgno_t));
+		printf("page %lu\n", (u_long)pgno);
+	} else {
+		obj = (u_int8_t *)lp + lp->obj - (u_int8_t *)lt->region;
+		printf("0x%lx ", (u_long)obj);
+		__db_pr(ptr, lockobj->lockobj.size);
+		printf("\n");
+	}
+}
+
+#endif
+
+static int
+__lock_count_locks(lrp)
+	DB_LOCKREGION *lrp;
+{
+	struct __db_lock *newl;
+	int count;
+
+	count = 0;
+	for (newl = SH_TAILQ_FIRST(&lrp->free_locks, __db_lock);
+	    newl != NULL;
+	    newl = SH_TAILQ_NEXT(newl, links, __db_lock))
+		count++;
+
+	return (count);
+}
+
+static int
+__lock_count_objs(lrp)
+	DB_LOCKREGION *lrp;
+{
+	DB_LOCKOBJ *obj;
+	int count;
+
+	count = 0;
+	for (obj = SH_TAILQ_FIRST(&lrp->free_objs, __db_lockobj);
+	    obj != NULL;
+	    obj = SH_TAILQ_NEXT(obj, links, __db_lockobj))
+		count++;
+
+	return (count);
+}
+
+/*
+ * PUBLIC: int __lock_getobj  __P((DB_LOCKTAB *,
+ * PUBLIC:     u_int32_t, DBT *, u_int32_t type, DB_LOCKOBJ **));
+ */
+int
+__lock_getobj(lt, locker, dbt, type, objp)
+	DB_LOCKTAB *lt;
+	u_int32_t locker, type;
+	DBT *dbt;
+	DB_LOCKOBJ **objp;
+{
+	DB_LOCKREGION *lrp;
+	DB_LOCKOBJ *sh_obj;
+	u_int32_t obj_size;
+	int ret;
+	void *p, *src;
+
+	lrp = lt->region;
+
+	/* Look up the object in the hash table. */
+	if (type == DB_LOCK_OBJTYPE) {
+		__db_hashlookup(lt->hashtab, __db_lockobj, links, dbt, sh_obj,
+		    lrp->table_size, __lock_ohash, __lock_cmp);
+		obj_size = dbt->size;
+	} else {
+		__db_hashlookup(lt->hashtab, __db_lockobj, links, locker,
+		    sh_obj, lrp->table_size, __lock_locker_hash,
+		    __lock_locker_cmp);
+		obj_size = sizeof(locker);
+	}
+
+	/*
+	 * If we found the object, then we can just return it.  If
+	 * we didn't find the object, then we need to create it.
+	 */
+	if (sh_obj == NULL) {
+		/* Create new object and then insert it into hash table. */
+		if ((sh_obj = SH_TAILQ_FIRST(&lrp->free_objs, __db_lockobj))
+		    == NULL) {
+			if ((ret = __lock_grow_region(lt, DB_LOCK_OBJ, 0)) != 0)
+				return (ret);
+			lrp = lt->region;
+			sh_obj = SH_TAILQ_FIRST(&lrp->free_objs, __db_lockobj);
+		}
+		if ((ret = __db_shalloc(lt->mem, obj_size, 0, &p)) != 0) {
+			if ((ret = __lock_grow_region(lt,
+			    DB_LOCK_MEM, obj_size)) != 0)
+				return (ret);
+			lrp = lt->region;
+			/* Reacquire the head of the list. */
+			sh_obj = SH_TAILQ_FIRST(&lrp->free_objs, __db_lockobj);
+			(void)__db_shalloc(lt->mem, obj_size, 0, &p);
+		}
+		sh_obj->type = type;
+		src = type == DB_LOCK_OBJTYPE ? dbt->data : (void *)&locker;
+		memcpy(p, src, obj_size);
+		SH_TAILQ_REMOVE(&lrp->free_objs, sh_obj, links, __db_lockobj);
+
+		SH_TAILQ_INIT(&sh_obj->waiters);
+		if (type == DB_LOCK_LOCKER)
+			SH_LIST_INIT(&sh_obj->heldby);
+		else
+			SH_TAILQ_INIT(&sh_obj->holders);
+		sh_obj->lockobj.size = obj_size;
+		sh_obj->lockobj.off = SH_PTR_TO_OFF(&sh_obj->lockobj, p);
+
+		__db_hashinsert(lt->hashtab, __db_lockobj, links, sh_obj,
+		    lrp->table_size, __lock_lhash);
+
+		if (type == DB_LOCK_LOCKER)
+			lrp->nlockers++;
+	}
+
+	*objp = sh_obj;
+	return (0);
+}
+
+/*
+ * Any lock on the waitlist has a process waiting for it.  Therefore, we
+ * can't return the lock to the freelist immediately.  Instead, we can
+ * remove the lock from the list of waiters, set the status field of the
+ * lock, and then let the process waking up return the lock to the
+ * free list.
+ */
+static void
+__lock_remove_waiter(lt, sh_obj, lockp, status)
+	DB_LOCKTAB *lt;
+	DB_LOCKOBJ *sh_obj;
+	struct __db_lock *lockp;
+	db_status_t status;
+{
+	SH_TAILQ_REMOVE(&sh_obj->waiters, lockp, links, __db_lock);
+	lockp->status = status;
+
+	/* Wake whoever is waiting on this lock. */
+	(void)__db_mutex_unlock(&lockp->mutex, lt->fd);
+}
+
+static void
+__lock_freeobj(lt, obj)
+	DB_LOCKTAB *lt;
+	DB_LOCKOBJ *obj;
+{
+	__db_hashremove_el(lt->hashtab, __db_lockobj, links,
+	    obj, lt->region->table_size, __lock_lhash);
+	__db_shalloc_free(lt->mem, SH_DBT_PTR(&obj->lockobj));
+	SH_TAILQ_INSERT_HEAD(&lt->region->free_objs, obj, links, __db_lockobj);
+}
+
+static void
+__lock_checklocker(lt, lockp, do_remove)
+	DB_LOCKTAB *lt;
+	struct __db_lock *lockp;
+	int do_remove;
+{
+	DB_LOCKOBJ *sh_locker;
+
+	if (do_remove)
+		SH_LIST_REMOVE(lockp, locker_links, __db_lock);
+
+	/* if the locker list is NULL, free up the object. */
+	if (__lock_getobj(lt, lockp->holder, NULL, DB_LOCK_LOCKER, &sh_locker)
+	    == 0 && SH_LIST_FIRST(&sh_locker->heldby, __db_lock) == NULL) {
+		__lock_freeobj(lt, sh_locker);
+		lt->region->nlockers--;
+	}
+}
+
+static void
+__lock_reset_region(lt)
+	DB_LOCKTAB *lt;
+{
+	lt->conflicts = (u_int8_t *)lt->region + sizeof(DB_LOCKREGION);
+	lt->hashtab =
+	    (DB_HASHTAB *)((u_int8_t *)lt->region + lt->region->hash_off);
+	lt->mem = (void *)((u_int8_t *)lt->region + lt->region->mem_off);
+	lt->reg_size = lt->region->hdr.size;
+}