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-rw-r--r--db2/hash/hash.c1440
1 files changed, 1440 insertions, 0 deletions
diff --git a/db2/hash/hash.c b/db2/hash/hash.c
new file mode 100644
index 0000000000..6d8c40057d
--- /dev/null
+++ b/db2/hash/hash.c
@@ -0,0 +1,1440 @@
+/*-
+ * See the file LICENSE for redistribution information.
+ *
+ * Copyright (c) 1996, 1997
+ *	Sleepycat Software.  All rights reserved.
+ */
+/*
+ * Copyright (c) 1990, 1993, 1994
+ *	Margo Seltzer.  All rights reserved.
+ */
+/*
+ * Copyright (c) 1990, 1993, 1994
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Margo Seltzer.
+ *
+ * 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[] = "@(#)hash.c	10.25 (Sleepycat) 8/24/97";
+#endif /* not lint */
+
+#ifndef NO_SYSTEM_INCLUDES
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#endif
+
+#include "shqueue.h"
+#include "db_int.h"
+#include "db_page.h"
+#include "db_am.h"
+#include "db_ext.h"
+#include "hash.h"
+#include "log.h"
+
+static int  __ham_c_close __P((DBC *));
+static int  __ham_c_del __P((DBC *, int));
+static int  __ham_c_get __P((DBC *, DBT *, DBT *, int));
+static int  __ham_c_put __P((DBC *, DBT *, DBT *, int));
+static int  __ham_c_init __P((DB *, DB_TXN *, DBC **));
+static int  __ham_cursor __P((DB *, DB_TXN *, DBC **));
+static int  __ham_delete __P((DB *, DB_TXN *, DBT *, int));
+static int  __ham_dup_return __P((HTAB *, HASH_CURSOR *, DBT *, int));
+static int  __ham_get __P((DB *, DB_TXN *, DBT *, DBT *, int));
+static void __ham_init_htab __P((HTAB *));
+static int  __ham_lookup __P((HTAB *,
+		HASH_CURSOR *, const DBT *, u_int32_t, db_lockmode_t));
+static int  __ham_overwrite __P((HTAB *, HASH_CURSOR *, DBT *));
+static int  __ham_put __P((DB *, DB_TXN *, DBT *, DBT *, int));
+static int  __ham_sync __P((DB *, int));
+
+/************************** INTERFACE ROUTINES ***************************/
+/* OPEN/CLOSE */
+
+/*
+ * __ham_open --
+ *
+ * PUBLIC: int __ham_open __P((DB *, DB_INFO *));
+ */
+int
+__ham_open(dbp, dbinfo)
+	DB *dbp;
+	DB_INFO *dbinfo;
+{
+	DB_ENV *dbenv;
+	DBC *curs;
+	HTAB *hashp;
+	int file_existed, ret;
+
+	dbenv = dbp->dbenv;
+
+	if ((hashp = (HTAB *)calloc(1, sizeof(HTAB))) == NULL)
+		return (ENOMEM);
+	hashp->dbp = dbp;
+
+	/* Set the hash function if specified by the user. */
+	if (dbinfo != NULL && dbinfo->h_hash != NULL)
+		hashp->hash = dbinfo->h_hash;
+
+	/*
+	 * Initialize the remaining fields of the dbp.  The type, close and
+	 * fd functions are all set in db_open.
+	 */
+	dbp->internal = hashp;
+	dbp->cursor = __ham_cursor;
+	dbp->del = __ham_delete;
+	dbp->get = __ham_get;
+	dbp->put = __ham_put;
+	dbp->sync = __ham_sync;
+
+	/* If locking is turned on, lock the meta data page. */
+	if (F_ISSET(dbp, DB_AM_LOCKING)) {
+		dbp->lock.pgno = BUCKET_INVALID;
+		if ((ret = lock_get(dbenv->lk_info, dbp->locker,
+		    0, &dbp->lock_dbt, DB_LOCK_READ, &hashp->hlock)) != 0) {
+			if (ret < 0)
+				ret = EAGAIN;
+			goto out;
+		}
+	}
+
+	/*
+	 * Now, we can try to read the meta-data page and figure out
+	 * if we set up locking and get the meta-data page properly.
+	 * If this is a new file, initialize it, and put it back dirty.
+	 */
+	if ((ret = __ham_get_page(hashp->dbp, 0, (PAGE **)&hashp->hdr)) != 0)
+		goto out;
+
+	/* Initialize the hashp structure */
+	if (hashp->hdr->magic == DB_HASHMAGIC) {
+		file_existed = 1;
+		/* File exists, verify the data in the header. */
+		if (hashp->hash == NULL)
+			hashp->hash =
+			    hashp->hdr->version < 5 ? __ham_func4 : __ham_func5;
+		if (hashp->hash(CHARKEY, sizeof(CHARKEY)) !=
+		    hashp->hdr->h_charkey) {
+			__db_err(hashp->dbp->dbenv,
+			    "hash: incompatible hash function");
+			ret = EINVAL;
+			goto out;
+		}
+		if (F_ISSET(hashp->hdr, DB_HASH_DUP))
+			F_SET(dbp, DB_AM_DUP);
+	} else {
+		/*
+		 * File does not exist, we must initialize the header.  If
+		 * locking is enabled that means getting a write lock first.
+		 */
+		file_existed = 0;
+		if (F_ISSET(dbp, DB_AM_LOCKING) &&
+		    ((ret = lock_put(dbenv->lk_info, hashp->hlock)) != 0 ||
+		    (ret = lock_get(dbenv->lk_info, dbp->locker, 0,
+		        &dbp->lock_dbt, DB_LOCK_WRITE, &hashp->hlock)) != 0)) {
+			if (ret < 0)
+				ret = EAGAIN;
+			goto out;
+		}
+
+		hashp->hdr->nelem = dbinfo != NULL ? dbinfo->h_nelem : 0;
+		hashp->hdr->ffactor =
+		    dbinfo != NULL && dbinfo->h_ffactor ? dbinfo->h_ffactor : 0;
+		__ham_init_htab(hashp);
+		if (F_ISSET(dbp, DB_AM_DUP))
+			F_SET(hashp->hdr, DB_HASH_DUP);
+		if ((ret = __ham_dirty_page(hashp, (PAGE *)hashp->hdr)) != 0)
+			goto out;
+	}
+
+	/* Initialize the default cursor. */
+	__ham_c_init(dbp, NULL, &curs);
+	TAILQ_INSERT_TAIL(&dbp->curs_queue, curs, links);
+
+	/* Allocate memory for our split buffer. */
+	if ((hashp->split_buf = (PAGE *)malloc(dbp->pgsize)) == NULL) {
+		ret = ENOMEM;
+		goto out;
+	}
+
+#ifdef NO_STATISTICS_FOR_DB_ERR
+	__db_err(dbp->dbenv,
+	    "%s%lx\n%s%ld\n%s%ld\n%s%ld\n%s%ld\n%s0x%lx\n%s0x%lx\n%s%ld\n%s%ld\n%s0x%lx",
+	    "TABLE POINTER   ", (long)hashp,
+	    "BUCKET SIZE     ", (long)hashp->hdr->pagesize,
+	    "FILL FACTOR     ", (long)hashp->hdr->ffactor,
+	    "MAX BUCKET      ", (long)hashp->hdr->max_bucket,
+	    "OVFL POINT      ", (long)hashp->hdr->ovfl_point,
+	    "LAST FREED      ", (long)hashp->hdr->last_freed,
+	    "HIGH MASK       ", (long)hashp->hdr->high_mask,
+	    "LOW  MASK       ", (long)hashp->hdr->low_mask,
+	    "NELEM           ", (long)hashp->hdr->nelem,
+	    "FLAGS           ", (long)hashp->hdr->flags);
+#endif
+
+	/* Release the meta data page */
+	(void)__ham_put_page(hashp->dbp, (PAGE *)hashp->hdr, 0);
+	if (F_ISSET(dbp, DB_AM_LOCKING) &&
+	    (ret = lock_put(dbenv->lk_info, hashp->hlock)) != 0) {
+		if (ret < 0)
+			ret = EAGAIN;
+		goto out;
+	}
+
+	hashp->hlock = 0;
+	hashp->hdr = NULL;
+	/* Sync the file so that we know that the meta data goes to disk. */
+	if (!file_existed && (ret = dbp->sync(dbp, 0)) != 0)
+		goto out;
+	return (0);
+
+out:	(void)__ham_close(dbp);
+	return (ret);
+}
+
+/*
+ * PUBLIC: int  __ham_close __P((DB *));
+ */
+int
+__ham_close(dbp)
+	DB *dbp;
+{
+	HTAB *hashp;
+	int ret, t_ret;
+
+	DEBUG_LWRITE(dbp, NULL, "ham_close", NULL, NULL, 0);
+	hashp = (HTAB *)dbp->internal;
+	ret = 0;
+
+	/* Free the split page. */
+	if (hashp->split_buf)
+		FREE(hashp->split_buf, dbp->pgsize);
+
+	if (hashp->hdr && (t_ret = __ham_put_page(hashp->dbp,
+	    (PAGE *)hashp->hdr, 0)) != 0 && ret == 0)
+		ret = t_ret;
+	if (hashp->hlock && (t_ret = lock_put(hashp->dbp->dbenv->lk_info,
+	    hashp->hlock)) != 0 && ret == 0)
+		ret = t_ret;
+
+	FREE(hashp, sizeof(HTAB));
+	dbp->internal = NULL;
+	return (ret);
+}
+
+/************************** LOCAL CREATION ROUTINES **********************/
+/*
+ * Returns 0 on No Error
+ */
+static void
+__ham_init_htab(hashp)
+	HTAB *hashp;
+{
+	u_int32_t nelem;
+	int32_t l2, nbuckets;
+
+	nelem = hashp->hdr->nelem;
+	hashp->hdr->pagesize = hashp->dbp->pgsize;
+	ZERO_LSN(hashp->hdr->lsn);
+	hashp->hdr->magic = DB_HASHMAGIC;
+	hashp->hdr->version = DB_HASHVERSION;
+	if (hashp->hash == NULL)
+		hashp->hash =
+		    hashp->hdr->version < 5 ? __ham_func4 : __ham_func5;
+	hashp->hdr->h_charkey = hashp->hash(CHARKEY, sizeof(CHARKEY));
+	if (nelem != 0 && hashp->hdr->ffactor != 0) {
+		nelem = (nelem - 1) / hashp->hdr->ffactor + 1;
+		l2 = __db_log2(nelem > 2 ? nelem : 2);
+	} else
+		l2 = 2;
+
+	nbuckets = 1 << l2;
+
+	hashp->hdr->spares[l2] = 0;
+	hashp->hdr->spares[l2 + 1] = 0;
+	hashp->hdr->ovfl_point = l2;
+	hashp->hdr->last_freed = PGNO_INVALID;
+
+	hashp->hdr->max_bucket = hashp->hdr->high_mask = nbuckets - 1;
+	hashp->hdr->low_mask = (nbuckets >> 1) - 1;
+	memcpy(hashp->hdr->uid, hashp->dbp->lock.fileid, DB_FILE_ID_LEN);
+}
+
+/********************** DESTROY/CLOSE ROUTINES ************************/
+
+
+/*
+ * Write modified pages to disk
+ *
+ * Returns:
+ *	 0 == OK
+ *	-1 ERROR
+ */
+static int
+__ham_sync(dbp, flags)
+	DB *dbp;
+	int flags;
+{
+	int ret;
+
+	DEBUG_LWRITE(dbp, NULL, "ham_sync", NULL, NULL, flags);
+	if ((ret = __db_syncchk(dbp, flags)) != 0)
+		return (ret);
+	if (F_ISSET(dbp, DB_AM_RDONLY))
+		return (0);
+
+	if ((ret = memp_fsync(dbp->mpf)) == DB_INCOMPLETE)
+		ret = 0;
+
+	return (ret);
+}
+
+/*******************************SEARCH ROUTINES *****************************/
+/*
+ * All the access routines return
+ *
+ * Returns:
+ *	 0 on SUCCESS
+ *	 1 to indicate an external ERROR (i.e. key not found, etc)
+ *	-1 to indicate an internal ERROR (i.e. out of memory, etc)
+ */
+
+static int
+__ham_get(dbp, txn, key, data, flags)
+	DB *dbp;
+	DB_TXN *txn;
+	DBT *key;
+	DBT *data;
+	int flags;
+{
+	DB *ldbp;
+	DBC *cp;
+	HTAB *hashp;
+	HASH_CURSOR *hcp;
+	int ret, t_ret;
+
+	DEBUG_LREAD(dbp, txn, "ham_get", key, NULL, flags);
+	if ((ret = __db_getchk(dbp, key, data, flags)) != 0)
+		return (ret);
+
+	ldbp = dbp;
+	if (F_ISSET(dbp, DB_AM_THREAD) &&
+	    (ret = __db_gethandle(dbp, __ham_hdup, &ldbp)) != 0)
+		return (ret);
+
+	hashp = (HTAB *)ldbp->internal;
+	SET_LOCKER(ldbp, txn);
+	GET_META(ldbp, hashp);
+	cp = TAILQ_FIRST(&ldbp->curs_queue);
+
+	hashp->hash_accesses++;
+	hcp = (HASH_CURSOR *)TAILQ_FIRST(&ldbp->curs_queue)->internal;
+	if ((ret = __ham_lookup(hashp, hcp, key, 0, DB_LOCK_READ)) == 0)
+		if (F_ISSET(hcp, H_OK))
+			ret = __ham_dup_return(hashp, hcp, data, DB_FIRST);
+		else /* Key was not found */
+			ret = DB_NOTFOUND;
+
+	if ((t_ret = __ham_item_done(hashp, hcp, 0)) != 0 && ret == 0)
+		ret = t_ret;
+	RELEASE_META(ldbp, hashp);
+	if (F_ISSET(dbp, DB_AM_THREAD))
+		__db_puthandle(ldbp);
+	return (ret);
+}
+
+static int
+__ham_put(dbp, txn, key, data, flags)
+	DB *dbp;
+	DB_TXN *txn;
+	DBT *key;
+	DBT *data;
+	int flags;
+{
+	DB *ldbp;
+	HTAB *hashp;
+	HASH_CURSOR *hcp;
+	DBT tmp_val, *myval;
+	int ret, t_ret;
+	u_int32_t nbytes;
+
+	DEBUG_LWRITE(dbp, txn, "ham_put", key, data, flags);
+	if ((ret = __db_putchk(dbp, key, data,
+	    flags, F_ISSET(dbp, DB_AM_RDONLY), F_ISSET(dbp, DB_AM_DUP))) != 0)
+		return (ret);
+
+	ldbp = dbp;
+	if (F_ISSET(dbp, DB_AM_THREAD) &&
+	    (ret = __db_gethandle(dbp, __ham_hdup, &ldbp)) != 0)
+		return (ret);
+
+	hashp = (HTAB *)ldbp->internal;
+	SET_LOCKER(ldbp, txn);
+	GET_META(ldbp, hashp);
+	hcp = TAILQ_FIRST(&ldbp->curs_queue)->internal;
+
+	nbytes = (ISBIG(hashp, key->size) ? HOFFPAGE_PSIZE :
+	    HKEYDATA_PSIZE(key->size)) +
+	    (ISBIG(hashp, data->size) ? HOFFPAGE_PSIZE :
+	    HKEYDATA_PSIZE(data->size));
+
+	hashp->hash_accesses++;
+	ret = __ham_lookup(hashp, hcp, key, nbytes, DB_LOCK_WRITE);
+
+	if (ret == DB_NOTFOUND) {
+		ret = 0;
+		if (hcp->seek_found_page != PGNO_INVALID &&
+		    hcp->seek_found_page != hcp->pgno) {
+			if ((ret = __ham_item_done(hashp, hcp, 0)) != 0)
+				goto out;
+			hcp->pgno = hcp->seek_found_page;
+			hcp->bndx = NDX_INVALID;
+		}
+
+		if (F_ISSET(data, DB_DBT_PARTIAL) && data->doff != 0) {
+			/*
+			 * Doing a partial put, but the key does not exist
+			 * and we are not beginning the write at 0.  We
+			 * must create a data item padded up to doff and
+			 * then write the new bytes represented by val.
+			 */
+			ret = __ham_init_dbt(&tmp_val, data->size + data->doff,
+			    &hcp->big_data, &hcp->big_datalen);
+			if (ret == 0) {
+				memset(tmp_val.data, 0, data->doff);
+				memcpy((u_int8_t *)tmp_val.data + data->doff,
+				    data->data, data->size);
+				myval = &tmp_val;
+			}
+		} else
+			myval = (DBT *)data;
+
+		if (ret == 0)
+			ret = __ham_add_el(hashp, hcp, key, myval, H_KEYDATA);
+	} else if (ret == 0 && F_ISSET(hcp, H_OK)) {
+		if (flags == DB_NOOVERWRITE)
+			ret = DB_KEYEXIST;
+		else if (F_ISSET(ldbp, DB_AM_DUP))
+			ret = __ham_add_dup(hashp, hcp, data, DB_KEYLAST);
+		else
+			ret = __ham_overwrite(hashp, hcp, data);
+	}
+
+	/* Free up all the cursor pages. */
+	if ((t_ret = __ham_item_done(hashp, hcp, ret == 0)) != 0 && ret == 0)
+		ret = t_ret;
+	/* Now check if we have to grow. */
+out:	if (ret == 0 && F_ISSET(hcp, H_EXPAND)) {
+		ret = __ham_expand_table(hashp);
+		F_CLR(hcp, H_EXPAND);
+	}
+
+	if ((t_ret = __ham_item_done(hashp, hcp, ret == 0)) != 0 && ret == 0)
+		ret = t_ret;
+	RELEASE_META(ldbp, hashp);
+	if (F_ISSET(dbp, DB_AM_THREAD))
+		__db_puthandle(ldbp);
+	return (ret);
+}
+
+static int
+__ham_cursor(dbp, txnid, dbcp)
+	DB *dbp;
+	DB_TXN *txnid;
+	DBC **dbcp;
+{
+	int ret;
+
+	DEBUG_LWRITE(dbp, txnid, "ham_cursor", NULL, NULL, 0);
+	if ((ret = __ham_c_init(dbp, txnid, dbcp)) != 0)
+		return (ret);
+
+	DB_THREAD_LOCK(dbp);
+	TAILQ_INSERT_TAIL(&dbp->curs_queue, *dbcp, links);
+	DB_THREAD_UNLOCK(dbp);
+	return (ret);
+}
+
+static int
+__ham_c_init(dbp, txnid, dbcp)
+	DB *dbp;
+	DB_TXN *txnid;
+	DBC **dbcp;
+{
+	DBC *db_curs;
+	HASH_CURSOR *new_curs;
+
+	if ((db_curs = (DBC *)calloc(sizeof(DBC), 1)) == NULL)
+		return (ENOMEM);
+
+	if ((new_curs =
+	    (HASH_CURSOR *)calloc(sizeof(struct cursor_t), 1)) == NULL) {
+		FREE(db_curs, sizeof(DBC));
+		return (ENOMEM);
+	}
+
+	db_curs->internal = new_curs;
+	db_curs->c_close = __ham_c_close;
+	db_curs->c_del = __ham_c_del;
+	db_curs->c_get = __ham_c_get;
+	db_curs->c_put = __ham_c_put;
+	db_curs->txn = txnid;
+	db_curs->dbp = dbp;
+
+	new_curs->db_cursor = db_curs;
+	__ham_item_init(new_curs);
+
+	if (dbcp != NULL)
+		*dbcp = db_curs;
+	return (0);
+}
+
+static int
+__ham_delete(dbp, txn, key, flags)
+	DB *dbp;
+	DB_TXN *txn;
+	DBT *key;
+	int flags;
+{
+	DB *ldbp;
+	HTAB *hashp;
+	HASH_CURSOR *hcp;
+	int ret, t_ret;
+
+	DEBUG_LWRITE(dbp, txn, "ham_delete", key, NULL, flags);
+	if ((ret = __db_delchk(dbp, flags, F_ISSET(dbp, DB_AM_RDONLY))) != 0)
+		return (ret);
+
+	ldbp = dbp;
+	if (F_ISSET(dbp, DB_AM_THREAD) &&
+	    (ret = __db_gethandle(dbp, __ham_hdup, &ldbp)) != 0)
+		return (ret);
+	hashp = (HTAB *)ldbp->internal;
+	SET_LOCKER(ldbp, txn);
+	GET_META(ldbp, hashp);
+	hcp = TAILQ_FIRST(&ldbp->curs_queue)->internal;
+
+	hashp->hash_accesses++;
+	if ((ret = __ham_lookup(hashp, hcp, key, 0, DB_LOCK_WRITE)) == 0)
+		if (F_ISSET(hcp, H_OK))
+			ret = __ham_del_pair(hashp, hcp);
+		else
+			ret = DB_NOTFOUND;
+
+	if ((t_ret = __ham_item_done(hashp, hcp, ret == 0)) != 0 && ret == 0)
+		ret = t_ret;
+	RELEASE_META(ldbp, hashp);
+	if (F_ISSET(dbp, DB_AM_THREAD))
+		__db_puthandle(ldbp);
+	return (ret);
+}
+
+/* ****************** CURSORS ********************************** */
+static int
+__ham_c_close(cursor)
+	DBC *cursor;
+{
+	DB  *ldbp;
+	HTAB *hashp;
+	HASH_CURSOR *hcp;
+	int ret;
+
+	DEBUG_LWRITE(cursor->dbp, cursor->txn, "ham_c_close", NULL, NULL, 0);
+	/*
+	 * If the pagep, dpagep, and lock fields of the cursor are all NULL,
+	 * then there really isn't a need to get a handle here.  However,
+	 * the normal case is that at least one of those fields is non-NULL,
+	 * and putting those checks in here would couple the ham_item_done
+	 * functionality with cursor close which would be pretty disgusting.
+	 * Instead, we pay the overhead here of always getting the handle.
+	 */
+	ldbp = cursor->dbp;
+	if (F_ISSET(cursor->dbp, DB_AM_THREAD) &&
+	    (ret = __db_gethandle(cursor->dbp, __ham_hdup, &ldbp)) != 0)
+		return (ret);
+	hashp = (HTAB *)ldbp->internal;
+	hcp = (HASH_CURSOR *)cursor->internal;
+	ret = __ham_item_done(hashp, hcp, 0);
+
+	if (hcp->big_key)
+		FREE(hcp->big_key, hcp->big_keylen);
+	if (hcp->big_data)
+		FREE(hcp->big_data, hcp->big_datalen);
+
+	/*
+	 * All cursors (except the default ones) are linked off the master.
+	 * Therefore, when we close the cursor, we have to remove it from
+	 * the master, not the local one.  When we are closing the file in
+	 * its entirety, then we clear the THREAD bit and the master and
+	 * local are identical, so we remove the correct one.
+	 */
+	DB_THREAD_LOCK(cursor->dbp);
+	TAILQ_REMOVE(&cursor->dbp->curs_queue, cursor, links);
+	DB_THREAD_UNLOCK(cursor->dbp);
+
+	if (F_ISSET(cursor->dbp, DB_AM_THREAD))
+		__db_puthandle(ldbp);
+
+	FREE(hcp, sizeof(HASH_CURSOR));
+	FREE(cursor, sizeof(DBC));
+	return (ret);
+}
+
+static int
+__ham_c_del(cursor, flags)
+	DBC *cursor;
+	int flags;
+{
+	DB *ldbp;
+	HTAB *hashp;
+	HASH_CURSOR *hcp;
+	HASH_CURSOR save_curs;
+	db_pgno_t ppgno, chg_pgno;
+	int ret, t_ret;
+
+	DEBUG_LWRITE(cursor->dbp, cursor->txn, "ham_c_del", NULL, NULL, flags);
+	ldbp = cursor->dbp;
+	if (F_ISSET(cursor->dbp, DB_AM_THREAD) &&
+	    (ret = __db_gethandle(cursor->dbp, __ham_hdup, &ldbp)) != 0)
+		return (ret);
+	hashp = (HTAB *)ldbp->internal;
+	hcp = (HASH_CURSOR *)cursor->internal;
+	save_curs = *hcp;
+	if ((ret = __db_cdelchk(ldbp, flags,
+	    F_ISSET(ldbp, DB_AM_RDONLY), IS_VALID(hcp))) != 0)
+		return (ret);
+	if (F_ISSET(hcp, H_DELETED))
+		return (DB_NOTFOUND);
+
+	SET_LOCKER(hashp->dbp, cursor->txn);
+	GET_META(hashp->dbp, hashp);
+	hashp->hash_accesses++;
+	if ((ret = __ham_get_cpage(hashp, hcp, DB_LOCK_WRITE)) != 0)
+		goto out;
+	if (F_ISSET(hcp, H_ISDUP) && hcp->dpgno != PGNO_INVALID) {
+		ppgno = PREV_PGNO(hcp->dpagep);
+
+		/* Remove item from duplicate page. */
+		chg_pgno = hcp->dpgno;
+		if ((ret = __db_drem(hashp->dbp,
+		    &hcp->dpagep, hcp->dndx, __ham_del_page)) != 0)
+			goto out;
+
+		/*
+		 * There are 4 cases.
+		 * 1. We removed an item on a page, but nothing else changed.
+		 * 2. We removed the last item on a page, but there is a
+		 *    following page of duplicates.
+		 * 3. We removed the last item on a page, this page was the
+		 *    last page in a duplicate set, but there were dups before
+		 *    it.
+		 * 4. We removed the last item on a page, removing the last
+		 *    duplicate.
+		 * In case 1 hcp->dpagep is unchanged.
+		 * In case 2 hcp->dpagep comes back pointing to the next dup
+		 *     page.
+		 * In case 3 hcp->dpagep comes back NULL.
+		 * In case 4 hcp->dpagep comes back NULL.
+		 */
+		if (hcp->dpagep == NULL) {
+			if (ppgno != PGNO_INVALID) {		/* Case 3 */
+				hcp->dpgno = ppgno;
+				if ((ret = __ham_get_cpage(hashp, hcp,
+				    DB_LOCK_READ)) != 0)
+					goto out;
+				hcp->dndx = NUM_ENT(hcp->dpagep);
+				F_SET(hcp, H_DELETED);
+			} else {				/* Case 4 */
+				ret = __ham_del_pair(hashp, hcp);
+				hcp->dpgno = PGNO_INVALID;
+				/*
+				 * Delpair updated the cursor queue, so we
+				 * don't have to do that here.
+				 */
+				chg_pgno = PGNO_INVALID;
+			}
+		} else if (PGNO(hcp->dpagep) != hcp->dpgno) {
+			hcp->dndx = 0;				/* Case 2 */
+			hcp->dpgno = PGNO(hcp->dpagep);
+			if (ppgno == PGNO_INVALID)
+				memcpy(P_ENTRY(hcp->pagep,
+				    H_DATAINDEX(hcp->bndx)) +
+				    SSZ(HOFFDUP, pgno), &hcp->dpgno,
+				    sizeof(db_pgno_t));
+			F_SET(hcp, H_DELETED);
+		} else					/* Case 1 */
+			F_SET(hcp, H_DELETED);
+		if (chg_pgno != PGNO_INVALID)
+			__ham_c_update(hashp, hcp, chg_pgno, 0, 0, 1);
+	} else if (F_ISSET(hcp, H_ISDUP)) {			/* on page */
+		if (hcp->dup_off == 0 && DUP_SIZE(hcp->dup_len) ==
+		    LEN_HDATA(hcp->pagep, hashp->hdr->pagesize, hcp->bndx))
+			ret = __ham_del_pair(hashp, hcp);
+		else {
+			DBT repldbt;
+
+			repldbt.flags = 0;
+			F_SET(&repldbt, DB_DBT_PARTIAL);
+			repldbt.doff = hcp->dup_off;
+			repldbt.dlen = DUP_SIZE(hcp->dup_len);
+			repldbt.size = 0;
+			ret = __ham_replpair(hashp, hcp, &repldbt, 0);
+			hcp->dup_tlen -= DUP_SIZE(hcp->dup_len);
+			__ham_c_update(hashp, hcp, hcp->pgno,
+			    DUP_SIZE(hcp->dup_len), 0, 1);
+			F_SET(hcp, H_DELETED);
+		}
+
+	} else
+		/* Not a duplicate */
+		ret = __ham_del_pair(hashp, hcp);
+
+out:	if ((t_ret = __ham_item_done(hashp, hcp, ret == 0)) != 0 && ret == 0)
+		t_ret = ret;
+	if (ret != 0)
+		*hcp = save_curs;
+	RELEASE_META(hashp->dbp, hashp);
+	if (F_ISSET(cursor->dbp, DB_AM_THREAD))
+		__db_puthandle(ldbp);
+	return (ret);
+}
+
+static int
+__ham_c_get(cursor, key, data, flags)
+	DBC *cursor;
+	DBT *key;
+	DBT *data;
+	int flags;
+{
+	DB *ldbp;
+	HTAB *hashp;
+	HASH_CURSOR *hcp, save_curs;
+	int get_key, ret, t_ret;
+
+	DEBUG_LREAD(cursor->dbp, cursor->txn, "ham_c_get",
+	    flags == DB_SET || flags == DB_SET_RANGE ? key : NULL,
+	    NULL, flags);
+	ldbp = cursor->dbp;
+	if (F_ISSET(cursor->dbp, DB_AM_THREAD) &&
+	    (ret = __db_gethandle(cursor->dbp, __ham_hdup, &ldbp)) != 0)
+		return (ret);
+	hashp = (HTAB *)(ldbp->internal);
+	hcp = (HASH_CURSOR *)cursor->internal;
+	save_curs = *hcp;
+	if ((ret =
+	    __db_cgetchk(hashp->dbp, key, data, flags, IS_VALID(hcp))) != 0)
+		return (ret);
+
+	SET_LOCKER(hashp->dbp, cursor->txn);
+	GET_META(hashp->dbp, hashp);
+	hashp->hash_accesses++;
+
+	hcp->seek_size = 0;
+
+	ret = 0;
+	get_key = 1;
+	switch (flags) {
+	case DB_PREV:
+		if (hcp->bucket != BUCKET_INVALID) {
+			ret = __ham_item_prev(hashp, hcp, DB_LOCK_READ);
+			break;
+		}
+		/* FALL THROUGH */
+	case DB_LAST:
+		ret = __ham_item_last(hashp, hcp, DB_LOCK_READ);
+		break;
+	case DB_FIRST:
+		ret = __ham_item_first(hashp, hcp, DB_LOCK_READ);
+		break;
+	case DB_NEXT:
+		if (hcp->bucket == BUCKET_INVALID)
+			hcp->bucket = 0;
+		ret = __ham_item_next(hashp, hcp, DB_LOCK_READ);
+		break;
+	case DB_SET:
+	case DB_SET_RANGE:
+		ret = __ham_lookup(hashp, hcp, key, 0, DB_LOCK_READ);
+		get_key = 0;
+		break;
+	case DB_CURRENT:
+		if (F_ISSET(hcp, H_DELETED)) {
+			ret = DB_KEYEMPTY;
+			goto out;
+		}
+
+		ret = __ham_item(hashp, hcp, DB_LOCK_READ);
+		break;
+	}
+
+	/*
+	 * Must always enter this loop to do error handling and
+	 * check for big key/data pair.
+	 */
+	while (1) {
+		if (ret != 0 && ret != DB_NOTFOUND)
+			goto out1;
+		else if (F_ISSET(hcp, H_OK)) {
+			/* Get the key. */
+			if (get_key && (ret = __db_ret(hashp->dbp, hcp->pagep,
+			    H_KEYINDEX(hcp->bndx), key, &hcp->big_key,
+			    &hcp->big_keylen)) != 0)
+				goto out1;
+
+			ret = __ham_dup_return(hashp, hcp, data, flags);
+			break;
+		} else if (!F_ISSET(hcp, H_NOMORE)) {
+			abort();
+			break;
+		}
+
+		/*
+		 * Ran out of entries in a bucket; change buckets.
+		 */
+		switch (flags) {
+			case DB_LAST:
+			case DB_PREV:
+				ret = __ham_item_done(hashp, hcp, 0);
+				if (hcp->bucket == 0) {
+					ret = DB_NOTFOUND;
+					goto out1;
+				}
+				hcp->bucket--;
+				hcp->bndx = NDX_INVALID;
+				if (ret == 0)
+					ret = __ham_item_prev(hashp,
+					    hcp, DB_LOCK_READ);
+				break;
+			case DB_FIRST:
+			case DB_NEXT:
+				ret = __ham_item_done(hashp, hcp, 0);
+				hcp->bndx = NDX_INVALID;
+				hcp->bucket++;
+				hcp->pgno = PGNO_INVALID;
+				hcp->pagep = NULL;
+				if (hcp->bucket > hashp->hdr->max_bucket) {
+					ret = DB_NOTFOUND;
+					goto out1;
+				}
+				if (ret == 0)
+					ret = __ham_item_next(hashp,
+					    hcp, DB_LOCK_READ);
+				break;
+			case DB_SET:
+			case DB_SET_RANGE:
+				/* Key not found. */
+				ret = DB_NOTFOUND;
+				goto out1;
+		}
+	}
+out1:	if ((t_ret = __ham_item_done(hashp, hcp, 0)) != 0 && ret == 0)
+		t_ret = ret;
+out:	if (ret)
+		*hcp = save_curs;
+	RELEASE_META(hashp->dbp, hashp);
+	if (F_ISSET(cursor->dbp, DB_AM_THREAD))
+		__db_puthandle(ldbp);
+	return (ret);
+}
+
+static int
+__ham_c_put(cursor, key, data, flags)
+	DBC *cursor;
+	DBT *key;
+	DBT *data;
+	int flags;
+{
+	DB *ldbp;
+	HTAB *hashp;
+	HASH_CURSOR *hcp, save_curs;
+	int ret, t_ret;
+	u_int32_t nbytes;
+
+	DEBUG_LWRITE(cursor->dbp, cursor->txn, "ham_c_put",
+	    flags == DB_KEYFIRST || flags == DB_KEYLAST ? key : NULL,
+	    NULL, flags);
+	ldbp = cursor->dbp;
+	if (F_ISSET(cursor->dbp, DB_AM_THREAD) &&
+	    (ret = __db_gethandle(cursor->dbp, __ham_hdup, &ldbp)) != 0)
+		return (ret);
+	hashp = (HTAB *)(ldbp->internal);
+	hcp = (HASH_CURSOR *)cursor->internal;
+	save_curs = *hcp;
+
+	if ((ret = __db_cputchk(hashp->dbp, key, data, flags,
+	    F_ISSET(ldbp, DB_AM_RDONLY), IS_VALID(hcp))) != 0)
+		return (ret);
+	if (F_ISSET(hcp, H_DELETED))
+		return (DB_NOTFOUND);
+
+	SET_LOCKER(hashp->dbp, cursor->txn);
+	GET_META(hashp->dbp, hashp);
+	ret = 0;
+
+	switch (flags) {
+	case DB_KEYLAST:
+	case DB_KEYFIRST:
+		nbytes = (ISBIG(hashp, key->size) ? HOFFPAGE_PSIZE :
+		    HKEYDATA_PSIZE(key->size)) +
+		    (ISBIG(hashp, data->size) ? HOFFPAGE_PSIZE :
+		    HKEYDATA_PSIZE(data->size));
+		ret = __ham_lookup(hashp, hcp, key, nbytes, DB_LOCK_WRITE);
+		break;
+	case DB_BEFORE:
+	case DB_AFTER:
+	case DB_CURRENT:
+		ret = __ham_item(hashp, hcp, DB_LOCK_WRITE);
+		break;
+	}
+
+	if (ret == 0) {
+		if (flags == DB_CURRENT && !F_ISSET(ldbp, DB_AM_DUP))
+			ret = __ham_overwrite(hashp, hcp, data);
+		else
+			ret = __ham_add_dup(hashp, hcp, data, flags);
+	}
+
+	if (ret == 0 && F_ISSET(hcp, H_EXPAND)) {
+		ret = __ham_expand_table(hashp);
+		F_CLR(hcp, H_EXPAND);
+	}
+
+	if ((t_ret = __ham_item_done(hashp, hcp, ret == 0)) != 0 && ret == 0)
+		ret = t_ret;
+	if (ret != 0)
+		*hcp = save_curs;
+	RELEASE_META(hashp->dbp, hashp);
+	if (F_ISSET(cursor->dbp, DB_AM_THREAD))
+		__db_puthandle(ldbp);
+	return (ret);
+}
+
+/********************************* UTILITIES ************************/
+
+/*
+ * __ham_expand_table --
+ *
+ * PUBLIC: int __ham_expand_table __P((HTAB *));
+ */
+int
+__ham_expand_table(hashp)
+	HTAB *hashp;
+{
+	u_int32_t old_bucket, new_bucket;
+	u_int32_t spare_ndx;
+	int ret;
+
+	ret = 0;
+	DIRTY_META(hashp, ret);
+	if (ret)
+		return (ret);
+
+	if (DB_LOGGING(hashp->dbp)) {
+		DB_LSN new_lsn;
+
+		if ((ret = __ham_splitmeta_log(hashp->dbp->dbenv->lg_info,
+		    (DB_TXN *)hashp->dbp->txn, &new_lsn, 0,
+		    hashp->dbp->log_fileid,
+		    hashp->hdr->max_bucket, hashp->hdr->ovfl_point,
+		    hashp->hdr->spares[hashp->hdr->ovfl_point],
+		    &hashp->hdr->lsn)) != 0)
+			return (ret);
+
+		hashp->hdr->lsn = new_lsn;
+	}
+
+	hashp->hash_expansions++;
+	new_bucket = ++hashp->hdr->max_bucket;
+	old_bucket = (hashp->hdr->max_bucket & hashp->hdr->low_mask);
+
+	/*
+	 * If the split point is increasing (hdr.max_bucket's log base 2
+	 * increases), max sure that we have enough extra pages, then
+	 * copy the current contents of the spare split bucket to the
+	 * next bucket.
+	 */
+	spare_ndx = __db_log2(hashp->hdr->max_bucket + 1);
+	if (spare_ndx > hashp->hdr->ovfl_point) {
+		/*
+		 * We are about to shift the split point.  Make sure that
+		 * if the next doubling is going to be big (more than 8
+		 * pages), we have some extra pages around.
+		 */
+		if (hashp->hdr->spares[hashp->hdr->ovfl_point] == 0 &&
+		    new_bucket >= 8)
+			__ham_init_ovflpages(hashp);
+
+		hashp->hdr->spares[spare_ndx] =
+		    hashp->hdr->spares[hashp->hdr->ovfl_point];
+		hashp->hdr->ovfl_point = spare_ndx;
+	}
+
+	if (new_bucket > hashp->hdr->high_mask) {
+		/* Starting a new doubling */
+		hashp->hdr->low_mask = hashp->hdr->high_mask;
+		hashp->hdr->high_mask = new_bucket | hashp->hdr->low_mask;
+	}
+
+	if (BUCKET_TO_PAGE(hashp, new_bucket) > MAX_PAGES(hashp)) {
+		__db_err(hashp->dbp->dbenv,
+		    "hash: Cannot allocate new bucket.  Pages exhausted.");
+		return (ENOSPC);
+	}
+
+	/* Relocate records to the new bucket */
+	return (__ham_split_page(hashp, old_bucket, new_bucket));
+}
+
+/*
+ * PUBLIC: u_int32_t __ham_call_hash __P((HTAB *, u_int8_t *, int32_t));
+ */
+u_int32_t
+__ham_call_hash(hashp, k, len)
+	HTAB *hashp;
+	u_int8_t *k;
+	int32_t len;
+{
+	u_int32_t n, bucket;
+
+	n = (u_int32_t)hashp->hash(k, len);
+	bucket = n & hashp->hdr->high_mask;
+	if (bucket > hashp->hdr->max_bucket)
+		bucket = bucket & hashp->hdr->low_mask;
+	return (bucket);
+}
+
+/*
+ * Check for duplicates, and call __db_ret appropriately.  Release
+ * everything held by the cursor.
+ */
+static int
+__ham_dup_return(hashp, hcp, val, flags)
+	HTAB *hashp;
+	HASH_CURSOR *hcp;
+	DBT *val;
+	int flags;
+{
+	HKEYDATA *hk;
+	PAGE *pp;
+	DBT *myval, tmp_val;
+	db_indx_t ndx;
+	db_pgno_t pgno;
+	u_int8_t type;
+	int indx, ret;
+	db_indx_t len;
+
+	/* Check for duplicate and return the first one. */
+	ndx = H_DATAINDEX(hcp->bndx);
+	type = GET_HKEYDATA(hcp->pagep, ndx)->type;
+	pp = hcp->pagep;
+	myval = val;
+
+	/*
+	 * There are 3 cases:
+	 * 1. We are not in duplicate, simply call db_ret.
+	 * 2. We are looking at keys and stumbled onto a duplicate.
+	 * 3. We are in the middle of a duplicate set. (ISDUP set)
+	 */
+
+	/*
+	 * Here we check for the case where we just stumbled onto a
+	 * duplicate.  In this case, we do initialization and then
+	 * let the normal duplicate code handle it.
+	 */
+	if (!F_ISSET(hcp, H_ISDUP))
+		if (type == H_DUPLICATE) {
+			F_SET(hcp, H_ISDUP);
+			hcp->dup_tlen = LEN_HDATA(hcp->pagep,
+			    hashp->hdr->pagesize, hcp->bndx);
+			hk = H_PAIRDATA(hcp->pagep, hcp->bndx);
+			if (flags == DB_LAST || flags == DB_PREV) {
+				hcp->dndx = 0;
+				hcp->dup_off = 0;
+				do {
+					memcpy(&len, hk->data + hcp->dup_off,
+					    sizeof(db_indx_t));
+					hcp->dup_off += DUP_SIZE(len);
+					hcp->dndx++;
+				} while (hcp->dup_off < hcp->dup_tlen);
+				hcp->dup_off -= DUP_SIZE(len);
+				hcp->dndx--;
+			} else {
+				memcpy(&len, hk->data, sizeof(db_indx_t));
+				hcp->dup_off = 0;
+				hcp->dndx = 0;
+			}
+			hcp->dup_len = len;
+		} else if (type == H_OFFDUP) {
+			F_SET(hcp, H_ISDUP);
+			memcpy(&pgno,
+			    P_ENTRY(hcp->pagep, ndx) + SSZ(HOFFDUP, pgno),
+			    sizeof(db_pgno_t));
+			if (flags == DB_LAST || flags == DB_PREV) {
+				indx = (int)hcp->dndx;
+				if ((ret = __db_dend(hashp->dbp,
+				    pgno, &hcp->dpagep)) != 0)
+					return (ret);
+				hcp->dpgno = PGNO(hcp->dpagep);
+				hcp->dndx = NUM_ENT(hcp->dpagep) - 1;
+			} else if ((ret = __ham_next_cpage(hashp,
+			    hcp, pgno, 0, H_ISDUP)) != 0)
+				return (ret);
+		}
+
+
+	/*
+	 * Now, everything is initialized, grab a duplicate if
+	 * necessary.
+	 */
+	if (F_ISSET(hcp, H_ISDUP))
+		if (hcp->dpgno != PGNO_INVALID) {
+			pp = hcp->dpagep;
+			ndx = hcp->dndx;
+		} else {
+			/*
+			 * Copy the DBT in case we are retrieving into
+			 * user memory and we need the parameters for
+			 * it.
+			 */
+			memcpy(&tmp_val, val, sizeof(*val));
+			F_SET(&tmp_val, DB_DBT_PARTIAL);
+			tmp_val.dlen = hcp->dup_len;
+			tmp_val.doff = hcp->dup_off + sizeof(db_indx_t);
+			myval = &tmp_val;
+		}
+
+
+	/*
+	 * Finally, if we had a duplicate, pp, ndx, and myval should be
+	 * set appropriately.
+	 */
+	if ((ret = __db_ret(hashp->dbp, pp, ndx, myval, &hcp->big_data,
+	    &hcp->big_datalen)) != 0)
+		return (ret);
+
+	/*
+	 * In case we sent a temporary off to db_ret, set the real
+	 * return values.
+	 */
+	val->data = myval->data;
+	val->size = myval->size;
+
+	return (0);
+}
+
+static int
+__ham_overwrite(hashp, hcp, nval)
+	HTAB *hashp;
+	HASH_CURSOR *hcp;
+	DBT *nval;
+{
+	DBT *myval, tmp_val;
+	HKEYDATA *hk;
+
+	if (F_ISSET(hashp->dbp, DB_AM_DUP))
+		return (__ham_add_dup(hashp, hcp, nval, DB_KEYLAST));
+	else if (!F_ISSET(nval, DB_DBT_PARTIAL)) {
+		/* Put/overwrite */
+		memcpy(&tmp_val, nval, sizeof(*nval));
+		F_SET(&tmp_val, DB_DBT_PARTIAL);
+		tmp_val.doff = 0;
+		hk = H_PAIRDATA(hcp->pagep, hcp->bndx);
+		if (hk->type == H_OFFPAGE)
+			memcpy(&tmp_val.dlen,
+			    (u_int8_t *)hk + SSZ(HOFFPAGE, tlen),
+			    sizeof(u_int32_t));
+		else
+			tmp_val.dlen = LEN_HDATA(hcp->pagep,
+			    hashp->hdr->pagesize,hcp->bndx);
+		myval = &tmp_val;
+	} else /* Regular partial put */
+		myval = nval;
+
+	return (__ham_replpair(hashp, hcp, myval, 0));
+}
+
+/*
+ * Given a key and a cursor, sets the cursor to the page/ndx on which
+ * the key resides.  If the key is found, the cursor H_OK flag is set
+ * and the pagep, bndx, pgno (dpagep, dndx, dpgno) fields are set.
+ * If the key is not found, the H_OK flag is not set.  If the sought
+ * field is non-0, the pagep, bndx, pgno (dpagep, dndx, dpgno) fields
+ * are set indicating where an add might take place.  If it is 0,
+ * non of the cursor pointer field are valid.
+ */
+static int
+__ham_lookup(hashp, hcp, key, sought, mode)
+	HTAB *hashp;
+	HASH_CURSOR *hcp;
+	const DBT *key;
+	u_int32_t sought;
+	db_lockmode_t mode;
+{
+	HKEYDATA *hk;
+	db_pgno_t pgno;
+	u_int32_t tlen;
+	int match, ret, t_ret;
+
+	/*
+	 * Set up cursor so that we're looking for space to add an item
+	 * as we cycle through the pages looking for the key.
+	 */
+	if ((ret = __ham_item_reset(hashp, hcp)) != 0)
+		return (ret);
+	hcp->seek_size = sought;
+
+	hcp->bucket = __ham_call_hash(hashp, (u_int8_t *)key->data, key->size);
+	while (1) {
+		if ((ret = __ham_item_next(hashp, hcp, mode)) != 0)
+			return (ret);
+
+		if (F_ISSET(hcp, H_NOMORE))
+			break;
+
+		hk = H_PAIRKEY(hcp->pagep, hcp->bndx);
+		switch (hk->type) {
+		case H_OFFPAGE:
+			memcpy(&tlen, (u_int8_t *)hk + SSZ(HOFFPAGE, tlen),
+			    sizeof(u_int32_t));
+			if (tlen == key->size) {
+				memcpy(&pgno,
+				    (u_int8_t *)hk + SSZ(HOFFPAGE, pgno),
+				    sizeof(db_pgno_t));
+				match = __db_moff(hashp->dbp, key, pgno);
+				if (match == 0) {
+					F_SET(hcp, H_OK);
+					return (0);
+				}
+			}
+			break;
+		case H_KEYDATA:
+			if (key->size == LEN_HKEY(hcp->pagep,
+			    hashp->hdr->pagesize, hcp->bndx) &&
+			    memcmp(key->data, hk->data, key->size) == 0) {
+				F_SET(hcp, H_OK);
+				return (0);
+			}
+			break;
+		case H_DUPLICATE:
+		case H_OFFDUP:
+			/*
+			 * These are errors because keys are never
+			 * duplicated, only data items are.
+			 */
+			return (__db_pgfmt(hashp->dbp, PGNO(hcp->pagep)));
+		}
+		hashp->hash_collisions++;
+	}
+
+	/*
+	 * Item was not found, adjust cursor properly.
+	 */
+
+	if (sought != 0)
+		return (ret);
+
+	if ((t_ret = __ham_item_done(hashp, hcp, 0)) != 0 && ret == 0)
+		ret = t_ret;
+	return (ret);
+}
+
+/*
+ * Initialize a dbt using some possibly already allocated storage
+ * for items.
+ * PUBLIC: int __ham_init_dbt __P((DBT *, u_int32_t, void **, u_int32_t *));
+ */
+int
+__ham_init_dbt(dbt, size, bufp, sizep)
+	DBT *dbt;
+	u_int32_t size;
+	void **bufp;
+	u_int32_t *sizep;
+{
+	memset(dbt, 0, sizeof(*dbt));
+	if (*sizep < size) {
+		if ((*bufp = (void *)(*bufp == NULL ?
+		    malloc(size) : realloc(*bufp, size))) == NULL) {
+			*sizep = 0;
+			return (ENOMEM);
+		}
+		*sizep = size;
+	}
+	dbt->data = *bufp;
+	dbt->size = size;
+	return (0);
+}
+
+/*
+ * Adjust the cursor after an insert or delete.  The cursor passed is
+ * the one that was operated upon; we just need to check any of the
+ * others.
+ *
+ * len indicates the length of the item added/deleted
+ * add indicates if the item indicated by the cursor has just been
+ * added (add == 1) or deleted (add == 0).
+ * dup indicates if the addition occurred into a duplicate set.
+ *
+ * PUBLIC: void __ham_c_update __P((HTAB *,
+ * PUBLIC:    HASH_CURSOR *, db_pgno_t, u_int32_t, int, int));
+ */
+void
+__ham_c_update(hashp, hcp, chg_pgno, len, add, dup)
+	HTAB *hashp;
+	HASH_CURSOR *hcp;
+	db_pgno_t chg_pgno;
+	u_int32_t len;
+	int add;
+	int dup;
+{
+	DBC *cp;
+	HTAB *hp;
+	HASH_CURSOR *lcp;
+	int page_deleted;
+
+	/*
+	 * Regular adds are always at the end of a given page,
+	 * so we never have to adjust anyone's cursor after
+	 * a regular add.
+	 */
+	if (!dup && add)
+		return;
+
+	page_deleted = chg_pgno != PGNO_INVALID &&
+	    ((!dup && chg_pgno != hcp->pgno) ||
+	    (dup && chg_pgno != hcp->dpgno));
+
+	hp = hcp->db_cursor->dbp->master->internal;
+	DB_THREAD_LOCK(hp->dbp);
+
+	for (cp = TAILQ_FIRST(&hp->dbp->curs_queue); cp != NULL;
+	    cp = TAILQ_NEXT(cp, links)) {
+		if (cp->internal == hcp)
+			continue;
+
+		lcp = (HASH_CURSOR *)cp->internal;
+
+		if (!dup && lcp->pgno != chg_pgno)
+			continue;
+
+		if (dup && F_ISSET(hcp, H_DELETED) && lcp->pgno != chg_pgno)
+			continue;
+
+		if (dup && !F_ISSET(hcp, H_DELETED) && lcp->dpgno != chg_pgno)
+			continue;
+
+		if (page_deleted) {
+			if (dup) {
+				lcp->dpgno = hcp->dpgno;
+				lcp->dndx = hcp->dndx;
+			} else {
+				lcp->pgno = hcp->pgno;
+				lcp->bndx = hcp->bndx;
+				lcp->bucket = hcp->bucket;
+			}
+			F_CLR(lcp, H_ISDUP);
+			continue;
+		}
+
+		if (!dup && lcp->bndx > hcp->bndx)
+			lcp->bndx--;
+		else if (!dup && lcp->bndx == hcp->bndx)
+			F_SET(lcp, H_DELETED);
+		else if (dup && lcp->bndx == hcp->bndx) {
+			/* Assign dpgno in case there was page conversion. */
+			lcp->dpgno = hcp->dpgno;
+			if (add && lcp->dndx >= hcp->dndx )
+				lcp->dndx++;
+			else if (!add && lcp->dndx > hcp->dndx)
+				lcp->dndx--;
+			else if (!add && lcp->dndx == hcp->dndx)
+				F_SET(lcp, H_DELETED);
+
+			/* Now adjust on-page information. */
+			if (lcp->dpgno == PGNO_INVALID)
+				if (add) {
+					lcp->dup_tlen += len;
+					if (lcp->dndx > hcp->dndx)
+						lcp->dup_off += len;
+				} else {
+					lcp->dup_tlen -= len;
+					if (lcp->dndx > hcp->dndx)
+						lcp->dup_off -= len;
+				}
+		}
+	}
+	DB_THREAD_UNLOCK(hp->dbp);
+}
+
+/*
+ * __ham_hdup --
+ *	This function gets called when we create a duplicate handle for a
+ *	threaded DB.  It should create the private part of the DB structure.
+ * PUBLIC: int  __ham_hdup __P((DB *, DB *));
+ */
+int
+__ham_hdup(orig, new)
+	DB *orig, *new;
+{
+	HTAB *hashp;
+	DBC *curs;
+	int ret;
+
+	if ((hashp = (HTAB *)malloc(sizeof(HTAB))) == NULL)
+		return (ENOMEM);
+
+	new->internal = hashp;
+
+	hashp->dbp = new;
+	hashp->hlock = 0;
+	hashp->hdr = NULL;
+	hashp->hash = ((HTAB *)orig->internal)->hash;
+	if ((hashp->split_buf = (PAGE *)malloc(orig->pgsize)) == NULL)
+		return (ENOMEM);
+	hashp->local_errno = 0;
+	hashp->hash_accesses = 0;
+	hashp->hash_collisions = 0;
+	hashp->hash_expansions = 0;
+	hashp->hash_overflows = 0;
+	hashp->hash_bigpages = 0;
+	/* Initialize the cursor queue. */
+	ret = __ham_c_init(new, NULL, &curs);
+	TAILQ_INSERT_TAIL(&new->curs_queue, curs, links);
+	return (ret);
+}