TDB2: Goodbye TDB2, Hello NTDB.

This renames everything from tdb2 to ntdb: importantly, we no longer
use the tdb_ namespace, so you can link against both ntdb and tdb if
you want to.

This also enables building of standalone ntdb by the autobuild script.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

67 files changed, 6358 insertions, 0 deletions

diff --git a/lib/ntdb/test/api-12-store.c b/lib/ntdb/test/api-12-store.c
new file mode 100644
index 0000000000..24d9498755
--- /dev/null
+++ b/lib/ntdb/test/api-12-store.c
@@ -0,0 +1,57 @@
+#include "config.h"
+#include "ntdb.h"
+#include "tap-interface.h"
+#include <ccan/hash/hash.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+#include "logging.h"
+
+/* We use the same seed which we saw a failure on. */
+static uint64_t fixedhash(const void *key, size_t len, uint64_t seed, void *p)
+{
+	return hash64_stable((const unsigned char *)key, len,
+			     *(uint64_t *)p);
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i, j;
+	struct ntdb_context *ntdb;
+	uint64_t seed = 16014841315512641303ULL;
+	union ntdb_attribute fixed_hattr
+		= { .hash = { .base = { NTDB_ATTRIBUTE_HASH },
+			      .fn = fixedhash,
+			      .data = &seed } };
+	int flags[] = { NTDB_INTERNAL, NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_INTERNAL|NTDB_CONVERT, NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT };
+	NTDB_DATA key = { (unsigned char *)&j, sizeof(j) };
+	NTDB_DATA data = { (unsigned char *)&j, sizeof(j) };
+
+	fixed_hattr.base.next = &tap_log_attr;
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * (1 + 500 * 3) + 1);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb = ntdb_open("run-12-store.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &fixed_hattr);
+		ok1(ntdb);
+		if (!ntdb)
+			continue;
+
+		/* We seemed to lose some keys.
+		 * Insert and check they're in there! */
+		for (j = 0; j < 500; j++) {
+			NTDB_DATA d = { NULL, 0 }; /* Bogus GCC warning */
+			ok1(ntdb_store(ntdb, key, data, NTDB_REPLACE) == 0);
+			ok1(ntdb_fetch(ntdb, key, &d) == NTDB_SUCCESS);
+			ok1(ntdb_deq(d, data));
+			free(d.dptr);
+		}
+		ntdb_close(ntdb);
+	}
+
+	ok1(tap_log_messages == 0);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/api-13-delete.c b/lib/ntdb/test/api-13-delete.c
new file mode 100644
index 0000000000..182252b109
--- /dev/null
+++ b/lib/ntdb/test/api-13-delete.c
@@ -0,0 +1,205 @@
+#include "private.h" // For NTDB_TOPLEVEL_HASH_BITS
+#include <ccan/hash/hash.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include "ntdb.h"
+#include "tap-interface.h"
+#include "logging.h"
+
+/* We rig the hash so adjacent-numbered records always clash. */
+static uint64_t clash(const void *key, size_t len, uint64_t seed, void *priv)
+{
+	return ((uint64_t)*(const unsigned int *)key)
+		<< (64 - NTDB_TOPLEVEL_HASH_BITS - 1);
+}
+
+/* We use the same seed which we saw a failure on. */
+static uint64_t fixedhash(const void *key, size_t len, uint64_t seed, void *p)
+{
+	return hash64_stable((const unsigned char *)key, len,
+			     *(uint64_t *)p);
+}
+
+static bool store_records(struct ntdb_context *ntdb)
+{
+	int i;
+	NTDB_DATA key = { (unsigned char *)&i, sizeof(i) };
+	NTDB_DATA d, data = { (unsigned char *)&i, sizeof(i) };
+
+	for (i = 0; i < 1000; i++) {
+		if (ntdb_store(ntdb, key, data, NTDB_REPLACE) != 0)
+			return false;
+		ntdb_fetch(ntdb, key, &d);
+		if (!ntdb_deq(d, data))
+			return false;
+		free(d.dptr);
+	}
+	return true;
+}
+
+static void test_val(struct ntdb_context *ntdb, uint64_t val)
+{
+	uint64_t v;
+	NTDB_DATA key = { (unsigned char *)&v, sizeof(v) };
+	NTDB_DATA d, data = { (unsigned char *)&v, sizeof(v) };
+
+	/* Insert an entry, then delete it. */
+	v = val;
+	/* Delete should fail. */
+	ok1(ntdb_delete(ntdb, key) == NTDB_ERR_NOEXIST);
+	ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+	/* Insert should succeed. */
+	ok1(ntdb_store(ntdb, key, data, NTDB_INSERT) == 0);
+	ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+	/* Delete should succeed. */
+	ok1(ntdb_delete(ntdb, key) == 0);
+	ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+	/* Re-add it, then add collision. */
+	ok1(ntdb_store(ntdb, key, data, NTDB_INSERT) == 0);
+	v = val + 1;
+	ok1(ntdb_store(ntdb, key, data, NTDB_INSERT) == 0);
+	ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+	/* Can find both? */
+	ok1(ntdb_fetch(ntdb, key, &d) == NTDB_SUCCESS);
+	ok1(d.dsize == data.dsize);
+	free(d.dptr);
+	v = val;
+	ok1(ntdb_fetch(ntdb, key, &d) == NTDB_SUCCESS);
+	ok1(d.dsize == data.dsize);
+	free(d.dptr);
+
+	/* Delete second one. */
+	v = val + 1;
+	ok1(ntdb_delete(ntdb, key) == 0);
+	ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+	/* Re-add */
+	ok1(ntdb_store(ntdb, key, data, NTDB_INSERT) == 0);
+	ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+	/* Now, try deleting first one. */
+	v = val;
+	ok1(ntdb_delete(ntdb, key) == 0);
+	ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+	/* Can still find second? */
+	v = val + 1;
+	ok1(ntdb_fetch(ntdb, key, &d) == NTDB_SUCCESS);
+	ok1(d.dsize == data.dsize);
+	free(d.dptr);
+
+	/* Now, this will be ideally placed. */
+	v = val + 2;
+	ok1(ntdb_store(ntdb, key, data, NTDB_INSERT) == 0);
+	ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+	/* This will collide with both. */
+	v = val;
+	ok1(ntdb_store(ntdb, key, data, NTDB_INSERT) == 0);
+
+	/* We can still find them all, right? */
+	ok1(ntdb_fetch(ntdb, key, &d) == NTDB_SUCCESS);
+	ok1(d.dsize == data.dsize);
+	free(d.dptr);
+	v = val + 1;
+	ok1(ntdb_fetch(ntdb, key, &d) == NTDB_SUCCESS);
+	ok1(d.dsize == data.dsize);
+	free(d.dptr);
+	v = val + 2;
+	ok1(ntdb_fetch(ntdb, key, &d) == NTDB_SUCCESS);
+	ok1(d.dsize == data.dsize);
+	free(d.dptr);
+
+	/* And if we delete val + 1, that val + 2 should not move! */
+	v = val + 1;
+	ok1(ntdb_delete(ntdb, key) == 0);
+	ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+	v = val;
+	ok1(ntdb_fetch(ntdb, key, &d) == NTDB_SUCCESS);
+	ok1(d.dsize == data.dsize);
+	free(d.dptr);
+	v = val + 2;
+	ok1(ntdb_fetch(ntdb, key, &d) == NTDB_SUCCESS);
+	ok1(d.dsize == data.dsize);
+	free(d.dptr);
+
+	/* Delete those two, so we are empty. */
+	ok1(ntdb_delete(ntdb, key) == 0);
+	v = val;
+	ok1(ntdb_delete(ntdb, key) == 0);
+
+	ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i, j;
+	struct ntdb_context *ntdb;
+	uint64_t seed = 16014841315512641303ULL;
+	union ntdb_attribute clash_hattr
+		= { .hash = { .base = { NTDB_ATTRIBUTE_HASH },
+			      .fn = clash } };
+	union ntdb_attribute fixed_hattr
+		= { .hash = { .base = { NTDB_ATTRIBUTE_HASH },
+			      .fn = fixedhash,
+			      .data = &seed } };
+	int flags[] = { NTDB_INTERNAL, NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_INTERNAL|NTDB_CONVERT, NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT };
+	/* These two values gave trouble before. */
+	int vals[] = { 755, 837 };
+
+	clash_hattr.base.next = &tap_log_attr;
+	fixed_hattr.base.next = &tap_log_attr;
+
+	plan_tests(sizeof(flags) / sizeof(flags[0])
+		   * (39 * 3 + 5 + sizeof(vals)/sizeof(vals[0])*2) + 1);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb = ntdb_open("run-13-delete.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &clash_hattr);
+		ok1(ntdb);
+		if (!ntdb)
+			continue;
+
+		/* Check start of hash table. */
+		test_val(ntdb, 0);
+
+		/* Check end of hash table. */
+		test_val(ntdb, -1ULL);
+
+		/* Check mixed bitpattern. */
+		test_val(ntdb, 0x123456789ABCDEF0ULL);
+
+		ok1(!ntdb->file || (ntdb->file->allrecord_lock.count == 0
+				   && ntdb->file->num_lockrecs == 0));
+		ntdb_close(ntdb);
+
+		/* Deleting these entries in the db gave problems. */
+		ntdb = ntdb_open("run-13-delete.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &fixed_hattr);
+		ok1(ntdb);
+		if (!ntdb)
+			continue;
+
+		ok1(store_records(ntdb));
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+		for (j = 0; j < sizeof(vals)/sizeof(vals[0]); j++) {
+			NTDB_DATA key;
+
+			key.dptr = (unsigned char *)&vals[j];
+			key.dsize = sizeof(vals[j]);
+			ok1(ntdb_delete(ntdb, key) == 0);
+			ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+		}
+		ntdb_close(ntdb);
+	}
+
+	ok1(tap_log_messages == 0);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/api-14-exists.c b/lib/ntdb/test/api-14-exists.c
new file mode 100644
index 0000000000..88663cad65
--- /dev/null
+++ b/lib/ntdb/test/api-14-exists.c
@@ -0,0 +1,54 @@
+#include "config.h"
+#include "ntdb.h"
+#include "tap-interface.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include "logging.h"
+
+static bool test_records(struct ntdb_context *ntdb)
+{
+	int i;
+	NTDB_DATA key = { (unsigned char *)&i, sizeof(i) };
+	NTDB_DATA data = { (unsigned char *)&i, sizeof(i) };
+
+	for (i = 0; i < 1000; i++) {
+		if (ntdb_exists(ntdb, key))
+			return false;
+		if (ntdb_store(ntdb, key, data, NTDB_REPLACE) != 0)
+			return false;
+		if (!ntdb_exists(ntdb, key))
+			return false;
+	}
+
+	for (i = 0; i < 1000; i++) {
+		if (!ntdb_exists(ntdb, key))
+			return false;
+		if (ntdb_delete(ntdb, key) != 0)
+			return false;
+		if (ntdb_exists(ntdb, key))
+			return false;
+	}
+	return true;
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_INTERNAL, NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_INTERNAL|NTDB_CONVERT, NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT };
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 2 + 1);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb = ntdb_open("run-14-exists.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		if (ok1(ntdb))
+			ok1(test_records(ntdb));
+		ntdb_close(ntdb);
+	}
+
+	ok1(tap_log_messages == 0);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/api-16-wipe_all.c b/lib/ntdb/test/api-16-wipe_all.c
new file mode 100644
index 0000000000..c1bda8e4f4
--- /dev/null
+++ b/lib/ntdb/test/api-16-wipe_all.c
@@ -0,0 +1,46 @@
+#include "config.h"
+#include "ntdb.h"
+#include "tap-interface.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include "logging.h"
+
+static bool add_records(struct ntdb_context *ntdb)
+{
+	int i;
+	NTDB_DATA key = { (unsigned char *)&i, sizeof(i) };
+	NTDB_DATA data = { (unsigned char *)&i, sizeof(i) };
+
+	for (i = 0; i < 1000; i++) {
+		if (ntdb_store(ntdb, key, data, NTDB_REPLACE) != 0)
+			return false;
+	}
+	return true;
+}
+
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_INTERNAL, NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_INTERNAL|NTDB_CONVERT, NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT };
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 4 + 1);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb = ntdb_open("run-16-wipe_all.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		if (ok1(ntdb)) {
+			NTDB_DATA key;
+			ok1(add_records(ntdb));
+			ok1(ntdb_wipe_all(ntdb) == NTDB_SUCCESS);
+			ok1(ntdb_firstkey(ntdb, &key) == NTDB_ERR_NOEXIST);
+			ntdb_close(ntdb);
+		}
+	}
+
+	ok1(tap_log_messages == 0);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/api-21-parse_record.c b/lib/ntdb/test/api-21-parse_record.c
new file mode 100644
index 0000000000..fa48562e17
--- /dev/null
+++ b/lib/ntdb/test/api-21-parse_record.c
@@ -0,0 +1,67 @@
+#include "config.h"
+#include "ntdb.h"
+#include "tap-interface.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include "logging.h"
+
+static enum NTDB_ERROR parse(NTDB_DATA key, NTDB_DATA data, NTDB_DATA *expected)
+{
+	if (!ntdb_deq(data, *expected))
+		return NTDB_ERR_EINVAL;
+	return NTDB_SUCCESS;
+}
+
+static enum NTDB_ERROR parse_err(NTDB_DATA key, NTDB_DATA data, void *unused)
+{
+	return 100;
+}
+
+static bool test_records(struct ntdb_context *ntdb)
+{
+	int i;
+	NTDB_DATA key = { (unsigned char *)&i, sizeof(i) };
+	NTDB_DATA data = { (unsigned char *)&i, sizeof(i) };
+
+	for (i = 0; i < 1000; i++) {
+		if (ntdb_store(ntdb, key, data, NTDB_REPLACE) != 0)
+			return false;
+	}
+
+	for (i = 0; i < 1000; i++) {
+		if (ntdb_parse_record(ntdb, key, parse, &data) != NTDB_SUCCESS)
+			return false;
+	}
+
+	if (ntdb_parse_record(ntdb, key, parse, &data) != NTDB_ERR_NOEXIST)
+		return false;
+
+	/* Test error return from parse function. */
+	i = 0;
+	if (ntdb_parse_record(ntdb, key, parse_err, NULL) != 100)
+		return false;
+
+	return true;
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_INTERNAL, NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_INTERNAL|NTDB_CONVERT, NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT };
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 2 + 1);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb = ntdb_open("api-21-parse_record.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		if (ok1(ntdb))
+			ok1(test_records(ntdb));
+		ntdb_close(ntdb);
+	}
+
+	ok1(tap_log_messages == 0);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/api-55-transaction.c b/lib/ntdb/test/api-55-transaction.c
new file mode 100644
index 0000000000..d51dd0b13e
--- /dev/null
+++ b/lib/ntdb/test/api-55-transaction.c
@@ -0,0 +1,73 @@
+#include "private.h" // struct ntdb_context
+#include "ntdb.h"
+#include "tap-interface.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include "logging.h"
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_context *ntdb;
+	unsigned char *buffer;
+	int flags[] = { NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_CONVERT, NTDB_NOMMAP|NTDB_CONVERT };
+	NTDB_DATA key = ntdb_mkdata("key", 3);
+	NTDB_DATA data;
+
+	buffer = malloc(1000);
+	for (i = 0; i < 1000; i++)
+		buffer[i] = i;
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 20 + 1);
+
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb = ntdb_open("run-55-transaction.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		ok1(ntdb);
+		if (!ntdb)
+			continue;
+
+		ok1(ntdb_transaction_start(ntdb) == 0);
+		data.dptr = buffer;
+		data.dsize = 1000;
+		ok1(ntdb_store(ntdb, key, data, NTDB_INSERT) == 0);
+		ok1(ntdb_fetch(ntdb, key, &data) == NTDB_SUCCESS);
+		ok1(data.dsize == 1000);
+		ok1(memcmp(data.dptr, buffer, data.dsize) == 0);
+		free(data.dptr);
+
+		/* Cancelling a transaction means no store */
+		ntdb_transaction_cancel(ntdb);
+		ok1(ntdb->file->allrecord_lock.count == 0
+		    && ntdb->file->num_lockrecs == 0);
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+		ok1(ntdb_fetch(ntdb, key, &data) == NTDB_ERR_NOEXIST);
+
+		/* Commit the transaction. */
+		ok1(ntdb_transaction_start(ntdb) == 0);
+		data.dptr = buffer;
+		data.dsize = 1000;
+		ok1(ntdb_store(ntdb, key, data, NTDB_INSERT) == 0);
+		ok1(ntdb_fetch(ntdb, key, &data) == NTDB_SUCCESS);
+		ok1(data.dsize == 1000);
+		ok1(memcmp(data.dptr, buffer, data.dsize) == 0);
+		free(data.dptr);
+		ok1(ntdb_transaction_commit(ntdb) == 0);
+		ok1(ntdb->file->allrecord_lock.count == 0
+		    && ntdb->file->num_lockrecs == 0);
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+		ok1(ntdb_fetch(ntdb, key, &data) == NTDB_SUCCESS);
+		ok1(data.dsize == 1000);
+		ok1(memcmp(data.dptr, buffer, data.dsize) == 0);
+		free(data.dptr);
+
+		ntdb_close(ntdb);
+	}
+
+	ok1(tap_log_messages == 0);
+	free(buffer);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/api-80-tdb_fd.c b/lib/ntdb/test/api-80-tdb_fd.c
new file mode 100644
index 0000000000..39a9df414e
--- /dev/null
+++ b/lib/ntdb/test/api-80-tdb_fd.c
@@ -0,0 +1,32 @@
+#include "config.h"
+#include "ntdb.h"
+#include "tap-interface.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include "logging.h"
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_INTERNAL, NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_INTERNAL|NTDB_CONVERT, NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT };
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 3);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb = ntdb_open("api-80-ntdb_fd.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		if (!ok1(ntdb))
+			continue;
+
+		if (flags[i] & NTDB_INTERNAL)
+			ok1(ntdb_fd(ntdb) == -1);
+		else
+			ok1(ntdb_fd(ntdb) > 2);
+		ntdb_close(ntdb);
+		ok1(tap_log_messages == 0);
+	}
+	return exit_status();
+}
diff --git a/lib/ntdb/test/api-81-seqnum.c b/lib/ntdb/test/api-81-seqnum.c
new file mode 100644
index 0000000000..93ad53ab07
--- /dev/null
+++ b/lib/ntdb/test/api-81-seqnum.c
@@ -0,0 +1,69 @@
+#include "config.h"
+#include "ntdb.h"
+#include "tap-interface.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include "logging.h"
+
+int main(int argc, char *argv[])
+{
+	unsigned int i, seq;
+	struct ntdb_context *ntdb;
+	NTDB_DATA d = { NULL, 0 }; /* Bogus GCC warning */
+	NTDB_DATA key = ntdb_mkdata("key", 3);
+	NTDB_DATA data = ntdb_mkdata("data", 4);
+	int flags[] = { NTDB_INTERNAL, NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_INTERNAL|NTDB_CONVERT, NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT };
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 15 + 4 * 13);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb = ntdb_open("api-81-seqnum.ntdb", flags[i]|NTDB_SEQNUM,
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		if (!ok1(ntdb))
+			continue;
+
+		seq = 0;
+		ok1(ntdb_get_seqnum(ntdb) == seq);
+		ok1(ntdb_store(ntdb, key, data, NTDB_INSERT) == 0);
+		ok1(ntdb_get_seqnum(ntdb) == ++seq);
+		/* Fetch doesn't change seqnum */
+		if (ok1(ntdb_fetch(ntdb, key, &d) == NTDB_SUCCESS))
+			free(d.dptr);
+		ok1(ntdb_get_seqnum(ntdb) == seq);
+		ok1(ntdb_append(ntdb, key, data) == NTDB_SUCCESS);
+		ok1(ntdb_get_seqnum(ntdb) == ++seq);
+
+		ok1(ntdb_delete(ntdb, key) == NTDB_SUCCESS);
+		ok1(ntdb_get_seqnum(ntdb) == ++seq);
+		/* Empty append works */
+		ok1(ntdb_append(ntdb, key, data) == NTDB_SUCCESS);
+		ok1(ntdb_get_seqnum(ntdb) == ++seq);
+
+		ok1(ntdb_wipe_all(ntdb) == NTDB_SUCCESS);
+		ok1(ntdb_get_seqnum(ntdb) == ++seq);
+
+		if (!(flags[i] & NTDB_INTERNAL)) {
+			ok1(ntdb_transaction_start(ntdb) == NTDB_SUCCESS);
+			ok1(ntdb_store(ntdb, key, data, NTDB_INSERT) == 0);
+			ok1(ntdb_get_seqnum(ntdb) == ++seq);
+			ok1(ntdb_append(ntdb, key, data) == NTDB_SUCCESS);
+			ok1(ntdb_get_seqnum(ntdb) == ++seq);
+			ok1(ntdb_delete(ntdb, key) == NTDB_SUCCESS);
+			ok1(ntdb_get_seqnum(ntdb) == ++seq);
+			ok1(ntdb_transaction_commit(ntdb) == NTDB_SUCCESS);
+			ok1(ntdb_get_seqnum(ntdb) == seq);
+
+			ok1(ntdb_transaction_start(ntdb) == NTDB_SUCCESS);
+			ok1(ntdb_store(ntdb, key, data, NTDB_INSERT) == 0);
+			ok1(ntdb_get_seqnum(ntdb) == seq + 1);
+			ntdb_transaction_cancel(ntdb);
+			ok1(ntdb_get_seqnum(ntdb) == seq);
+		}
+		ntdb_close(ntdb);
+		ok1(tap_log_messages == 0);
+	}
+	return exit_status();
+}
diff --git a/lib/ntdb/test/api-82-lockattr.c b/lib/ntdb/test/api-82-lockattr.c
new file mode 100644
index 0000000000..51bb939f59
--- /dev/null
+++ b/lib/ntdb/test/api-82-lockattr.c
@@ -0,0 +1,237 @@
+#include "private.h" // for ntdb_fcntl_unlock
+#include "ntdb.h"
+#include "tap-interface.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <errno.h>
+#include "logging.h"
+
+static int mylock(int fd, int rw, off_t off, off_t len, bool waitflag,
+		  void *_err)
+{
+	int *lock_err = _err;
+	struct flock fl;
+	int ret;
+
+	if (*lock_err) {
+		errno = *lock_err;
+		return -1;
+	}
+
+	do {
+		fl.l_type = rw;
+		fl.l_whence = SEEK_SET;
+		fl.l_start = off;
+		fl.l_len = len;
+
+		if (waitflag)
+			ret = fcntl(fd, F_SETLKW, &fl);
+		else
+			ret = fcntl(fd, F_SETLK, &fl);
+	} while (ret != 0 && errno == EINTR);
+
+	return ret;
+}
+
+static int trav_err;
+static int trav(struct ntdb_context *ntdb, NTDB_DATA k, NTDB_DATA d, int *terr)
+{
+	*terr = trav_err;
+	return 0;
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_CONVERT, NTDB_NOMMAP|NTDB_CONVERT };
+	union ntdb_attribute lock_attr;
+	NTDB_DATA key = ntdb_mkdata("key", 3);
+	NTDB_DATA data = ntdb_mkdata("data", 4);
+	int lock_err;
+
+	lock_attr.base.attr = NTDB_ATTRIBUTE_FLOCK;
+	lock_attr.base.next = &tap_log_attr;
+	lock_attr.flock.lock = mylock;
+	lock_attr.flock.unlock = ntdb_fcntl_unlock;
+	lock_attr.flock.data = &lock_err;
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 80);
+
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		NTDB_DATA d;
+
+		/* Nonblocking open; expect no error message. */
+		lock_err = EAGAIN;
+		ntdb = ntdb_open("run-82-lockattr.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &lock_attr);
+		ok(errno == lock_err, "Errno is %u", errno);
+		ok1(!ntdb);
+		ok1(tap_log_messages == 0);
+
+		lock_err = EINTR;
+		ntdb = ntdb_open("run-82-lockattr.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &lock_attr);
+		ok(errno == lock_err, "Errno is %u", errno);
+		ok1(!ntdb);
+		ok1(tap_log_messages == 0);
+
+		/* Forced fail open. */
+		lock_err = ENOMEM;
+		ntdb = ntdb_open("run-82-lockattr.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &lock_attr);
+		ok1(errno == lock_err);
+		ok1(!ntdb);
+		ok1(tap_log_messages == 1);
+		tap_log_messages = 0;
+
+		lock_err = 0;
+		ntdb = ntdb_open("run-82-lockattr.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &lock_attr);
+		if (!ok1(ntdb))
+			continue;
+		ok1(tap_log_messages == 0);
+
+		/* Nonblocking store. */
+		lock_err = EAGAIN;
+		ok1(ntdb_store(ntdb, key, data, NTDB_REPLACE) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 0);
+		lock_err = EINTR;
+		ok1(ntdb_store(ntdb, key, data, NTDB_REPLACE) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 0);
+		lock_err = ENOMEM;
+		ok1(ntdb_store(ntdb, key, data, NTDB_REPLACE) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 1);
+		tap_log_messages = 0;
+
+		/* Nonblocking fetch. */
+		lock_err = EAGAIN;
+		ok1(!ntdb_exists(ntdb, key));
+		ok1(tap_log_messages == 0);
+		lock_err = EINTR;
+		ok1(!ntdb_exists(ntdb, key));
+		ok1(tap_log_messages == 0);
+		lock_err = ENOMEM;
+		ok1(!ntdb_exists(ntdb, key));
+		ok1(tap_log_messages == 1);
+		tap_log_messages = 0;
+
+		lock_err = EAGAIN;
+		ok1(ntdb_fetch(ntdb, key, &d) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 0);
+		lock_err = EINTR;
+		ok1(ntdb_fetch(ntdb, key, &d) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 0);
+		lock_err = ENOMEM;
+		ok1(ntdb_fetch(ntdb, key, &d) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 1);
+		tap_log_messages = 0;
+
+		/* Nonblocking delete. */
+		lock_err = EAGAIN;
+		ok1(ntdb_delete(ntdb, key) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 0);
+		lock_err = EINTR;
+		ok1(ntdb_delete(ntdb, key) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 0);
+		lock_err = ENOMEM;
+		ok1(ntdb_delete(ntdb, key) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 1);
+		tap_log_messages = 0;
+
+		/* Nonblocking locks. */
+		lock_err = EAGAIN;
+		ok1(ntdb_chainlock(ntdb, key) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 0);
+		lock_err = EINTR;
+		ok1(ntdb_chainlock(ntdb, key) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 0);
+		lock_err = ENOMEM;
+		ok1(ntdb_chainlock(ntdb, key) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 1);
+		tap_log_messages = 0;
+
+		lock_err = EAGAIN;
+		ok1(ntdb_chainlock_read(ntdb, key) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 0);
+		lock_err = EINTR;
+		ok1(ntdb_chainlock_read(ntdb, key) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 0);
+		lock_err = ENOMEM;
+		ok1(ntdb_chainlock_read(ntdb, key) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 1);
+		tap_log_messages = 0;
+
+		lock_err = EAGAIN;
+		ok1(ntdb_lockall(ntdb) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 0);
+		lock_err = EINTR;
+		ok1(ntdb_lockall(ntdb) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 0);
+		lock_err = ENOMEM;
+		ok1(ntdb_lockall(ntdb) == NTDB_ERR_LOCK);
+		/* This actually does divide and conquer. */
+		ok1(tap_log_messages > 0);
+		tap_log_messages = 0;
+
+		lock_err = EAGAIN;
+		ok1(ntdb_lockall_read(ntdb) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 0);
+		lock_err = EINTR;
+		ok1(ntdb_lockall_read(ntdb) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 0);
+		lock_err = ENOMEM;
+		ok1(ntdb_lockall_read(ntdb) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages > 0);
+		tap_log_messages = 0;
+
+		/* Nonblocking traverse; go nonblock partway through. */
+		lock_err = 0;
+		ok1(ntdb_store(ntdb, key, data, NTDB_REPLACE) == 0);
+		trav_err = EAGAIN;
+		ok1(ntdb_traverse(ntdb, trav, &lock_err) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 0);
+		trav_err = EINTR;
+		lock_err = 0;
+		ok1(ntdb_traverse(ntdb, trav, &lock_err) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 0);
+		trav_err = ENOMEM;
+		lock_err = 0;
+		ok1(ntdb_traverse(ntdb, trav, &lock_err) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 1);
+		tap_log_messages = 0;
+
+		/* Nonblocking transactions. */
+		lock_err = EAGAIN;
+		ok1(ntdb_transaction_start(ntdb) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 0);
+		lock_err = EINTR;
+		ok1(ntdb_transaction_start(ntdb) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 0);
+		lock_err = ENOMEM;
+		ok1(ntdb_transaction_start(ntdb) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 1);
+		tap_log_messages = 0;
+
+		/* Nonblocking transaction prepare. */
+		lock_err = 0;
+		ok1(ntdb_transaction_start(ntdb) == 0);
+		ok1(ntdb_delete(ntdb, key) == 0);
+
+		lock_err = EAGAIN;
+		ok1(ntdb_transaction_prepare_commit(ntdb) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 0);
+
+		lock_err = 0;
+		ok1(ntdb_transaction_prepare_commit(ntdb) == 0);
+		ok1(ntdb_transaction_commit(ntdb) == 0);
+
+		/* And the transaction was committed, right? */
+		ok1(!ntdb_exists(ntdb, key));
+		ntdb_close(ntdb);
+		ok1(tap_log_messages == 0);
+	}
+	return exit_status();
+}
diff --git a/lib/ntdb/test/api-83-openhook.c b/lib/ntdb/test/api-83-openhook.c
new file mode 100644
index 0000000000..9f474c9ab8
--- /dev/null
+++ b/lib/ntdb/test/api-83-openhook.c
@@ -0,0 +1,96 @@
+#include "config.h"
+#include "ntdb.h"
+#include "tap-interface.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <stdarg.h>
+#include <unistd.h>
+#include "external-agent.h"
+#include "logging.h"
+
+static enum NTDB_ERROR clear_if_first(int fd, void *arg)
+{
+/* We hold a lock offset 4 always, so we can tell if anyone is holding it.
+ * (This is compatible with tdb's TDB_CLEAR_IF_FIRST flag).  */
+	struct flock fl;
+
+	if (arg != clear_if_first)
+		return NTDB_ERR_CORRUPT;
+
+	fl.l_type = F_WRLCK;
+	fl.l_whence = SEEK_SET;
+	fl.l_start = 4;
+	fl.l_len = 1;
+
+	if (fcntl(fd, F_SETLK, &fl) == 0) {
+		/* We must be first ones to open it! */
+		diag("truncating file!");
+		if (ftruncate(fd, 0) != 0) {
+			return NTDB_ERR_IO;
+		}
+	}
+	fl.l_type = F_RDLCK;
+	if (fcntl(fd, F_SETLKW, &fl) != 0) {
+		return NTDB_ERR_IO;
+	}
+	return NTDB_SUCCESS;
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_context *ntdb;
+	struct agent *agent;
+	union ntdb_attribute cif;
+	NTDB_DATA key = ntdb_mkdata("key", 3);
+	int flags[] = { NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_CONVERT, NTDB_NOMMAP|NTDB_CONVERT };
+
+	cif.openhook.base.attr = NTDB_ATTRIBUTE_OPENHOOK;
+	cif.openhook.base.next = &tap_log_attr;
+	cif.openhook.fn = clear_if_first;
+	cif.openhook.data = clear_if_first;
+
+	agent = prepare_external_agent();
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 13);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		/* Create it */
+		ntdb = ntdb_open("run-83-openhook.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, NULL);
+		ok1(ntdb);
+		ok1(ntdb_store(ntdb, key, key, NTDB_REPLACE) == 0);
+		ntdb_close(ntdb);
+
+		/* Now, open with CIF, should clear it. */
+		ntdb = ntdb_open("run-83-openhook.ntdb", flags[i],
+			       O_RDWR, 0, &cif);
+		ok1(ntdb);
+		ok1(!ntdb_exists(ntdb, key));
+		ok1(ntdb_store(ntdb, key, key, NTDB_REPLACE) == 0);
+
+		/* Agent should not clear it, since it's still open. */
+		ok1(external_agent_operation(agent, OPEN_WITH_HOOK,
+					     "run-83-openhook.ntdb") == SUCCESS);
+		ok1(external_agent_operation(agent, FETCH, "key") == SUCCESS);
+		ok1(external_agent_operation(agent, CLOSE, "") == SUCCESS);
+
+		/* Still exists for us too. */
+		ok1(ntdb_exists(ntdb, key));
+
+		/* Close it, now agent should clear it. */
+		ntdb_close(ntdb);
+
+		ok1(external_agent_operation(agent, OPEN_WITH_HOOK,
+					     "run-83-openhook.ntdb") == SUCCESS);
+		ok1(external_agent_operation(agent, FETCH, "key") == FAILED);
+		ok1(external_agent_operation(agent, CLOSE, "") == SUCCESS);
+
+		ok1(tap_log_messages == 0);
+	}
+
+	free_external_agent(agent);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/api-91-get-stats.c b/lib/ntdb/test/api-91-get-stats.c
new file mode 100644
index 0000000000..786885b44c
--- /dev/null
+++ b/lib/ntdb/test/api-91-get-stats.c
@@ -0,0 +1,57 @@
+#include "config.h"
+#include "ntdb.h"
+#include "tap-interface.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include "logging.h"
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_CONVERT, NTDB_NOMMAP|NTDB_CONVERT };
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 11);
+
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		union ntdb_attribute *attr;
+		NTDB_DATA key = ntdb_mkdata("key", 3);
+
+		ntdb = ntdb_open("run-91-get-stats.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		ok1(ntdb);
+		ok1(ntdb_store(ntdb, key, key, NTDB_REPLACE) == 0);
+
+		/* Use malloc so valgrind will catch overruns. */
+		attr = malloc(sizeof *attr);
+		attr->stats.base.attr = NTDB_ATTRIBUTE_STATS;
+		attr->stats.size = sizeof(*attr);
+
+		ok1(ntdb_get_attribute(ntdb, attr) == 0);
+		ok1(attr->stats.size == sizeof(*attr));
+		ok1(attr->stats.allocs > 0);
+		ok1(attr->stats.expands > 0);
+		ok1(attr->stats.locks > 0);
+		free(attr);
+
+		/* Try short one. */
+		attr = malloc(offsetof(struct ntdb_attribute_stats, allocs)
+			      + sizeof(attr->stats.allocs));
+		attr->stats.base.attr = NTDB_ATTRIBUTE_STATS;
+		attr->stats.size = offsetof(struct ntdb_attribute_stats, allocs)
+			+ sizeof(attr->stats.allocs);
+		ok1(ntdb_get_attribute(ntdb, attr) == 0);
+		ok1(attr->stats.size == sizeof(*attr));
+		ok1(attr->stats.allocs > 0);
+		free(attr);
+		ok1(tap_log_messages == 0);
+
+		ntdb_close(ntdb);
+
+	}
+	return exit_status();
+}
diff --git a/lib/ntdb/test/api-92-get-set-readonly.c b/lib/ntdb/test/api-92-get-set-readonly.c
new file mode 100644
index 0000000000..7abd304eef
--- /dev/null
+++ b/lib/ntdb/test/api-92-get-set-readonly.c
@@ -0,0 +1,105 @@
+#include "config.h"
+#include "ntdb.h"
+#include "tap-interface.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include "logging.h"
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_context *ntdb;
+	NTDB_DATA key = ntdb_mkdata("key", 3);
+	NTDB_DATA data = ntdb_mkdata("data", 4);
+	int flags[] = { NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_CONVERT, NTDB_NOMMAP|NTDB_CONVERT };
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 48);
+
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		/* RW -> R0 */
+		ntdb = ntdb_open("run-92-get-set-readonly.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		ok1(ntdb);
+		ok1(!(ntdb_get_flags(ntdb) & NTDB_RDONLY));
+
+		ok1(ntdb_store(ntdb, key, data, NTDB_INSERT) == NTDB_SUCCESS);
+
+		ntdb_add_flag(ntdb, NTDB_RDONLY);
+		ok1(ntdb_get_flags(ntdb) & NTDB_RDONLY);
+
+		/* Can't store, append, delete. */
+		ok1(ntdb_store(ntdb, key, data, NTDB_MODIFY) == NTDB_ERR_RDONLY);
+		ok1(tap_log_messages == 1);
+		ok1(ntdb_append(ntdb, key, data) == NTDB_ERR_RDONLY);
+		ok1(tap_log_messages == 2);
+		ok1(ntdb_delete(ntdb, key) == NTDB_ERR_RDONLY);
+		ok1(tap_log_messages == 3);
+
+		/* Can't start a transaction, or any write lock. */
+		ok1(ntdb_transaction_start(ntdb) == NTDB_ERR_RDONLY);
+		ok1(tap_log_messages == 4);
+		ok1(ntdb_chainlock(ntdb, key) == NTDB_ERR_RDONLY);
+		ok1(tap_log_messages == 5);
+		ok1(ntdb_lockall(ntdb) == NTDB_ERR_RDONLY);
+		ok1(tap_log_messages == 6);
+		ok1(ntdb_wipe_all(ntdb) == NTDB_ERR_RDONLY);
+		ok1(tap_log_messages == 7);
+
+		/* Back to RW. */
+		ntdb_remove_flag(ntdb, NTDB_RDONLY);
+		ok1(!(ntdb_get_flags(ntdb) & NTDB_RDONLY));
+
+		ok1(ntdb_store(ntdb, key, data, NTDB_MODIFY) == NTDB_SUCCESS);
+		ok1(ntdb_append(ntdb, key, data) == NTDB_SUCCESS);
+		ok1(ntdb_delete(ntdb, key) == NTDB_SUCCESS);
+
+		ok1(ntdb_transaction_start(ntdb) == NTDB_SUCCESS);
+		ok1(ntdb_store(ntdb, key, data, NTDB_INSERT) == NTDB_SUCCESS);
+		ok1(ntdb_transaction_commit(ntdb) == NTDB_SUCCESS);
+
+		ok1(ntdb_chainlock(ntdb, key) == NTDB_SUCCESS);
+		ntdb_chainunlock(ntdb, key);
+		ok1(ntdb_lockall(ntdb) == NTDB_SUCCESS);
+		ntdb_unlockall(ntdb);
+		ok1(ntdb_wipe_all(ntdb) == NTDB_SUCCESS);
+		ok1(tap_log_messages == 7);
+
+		ntdb_close(ntdb);
+
+		/* R0 -> RW */
+		ntdb = ntdb_open("run-92-get-set-readonly.ntdb", flags[i],
+			       O_RDONLY, 0600, &tap_log_attr);
+		ok1(ntdb);
+		ok1(ntdb_get_flags(ntdb) & NTDB_RDONLY);
+
+		/* Can't store, append, delete. */
+		ok1(ntdb_store(ntdb, key, data, NTDB_INSERT) == NTDB_ERR_RDONLY);
+		ok1(tap_log_messages == 8);
+		ok1(ntdb_append(ntdb, key, data) == NTDB_ERR_RDONLY);
+		ok1(tap_log_messages == 9);
+		ok1(ntdb_delete(ntdb, key) == NTDB_ERR_RDONLY);
+		ok1(tap_log_messages == 10);
+
+		/* Can't start a transaction, or any write lock. */
+		ok1(ntdb_transaction_start(ntdb) == NTDB_ERR_RDONLY);
+		ok1(tap_log_messages == 11);
+		ok1(ntdb_chainlock(ntdb, key) == NTDB_ERR_RDONLY);
+		ok1(tap_log_messages == 12);
+		ok1(ntdb_lockall(ntdb) == NTDB_ERR_RDONLY);
+		ok1(tap_log_messages == 13);
+		ok1(ntdb_wipe_all(ntdb) == NTDB_ERR_RDONLY);
+		ok1(tap_log_messages == 14);
+
+		/* Can't remove NTDB_RDONLY since we opened with O_RDONLY */
+		ntdb_remove_flag(ntdb, NTDB_RDONLY);
+		ok1(tap_log_messages == 15);
+		ok1(ntdb_get_flags(ntdb) & NTDB_RDONLY);
+		ntdb_close(ntdb);
+
+		ok1(tap_log_messages == 15);
+		tap_log_messages = 0;
+	}
+	return exit_status();
+}
diff --git a/lib/ntdb/test/api-93-repack.c b/lib/ntdb/test/api-93-repack.c
new file mode 100644
index 0000000000..168bc24c0a
--- /dev/null
+++ b/lib/ntdb/test/api-93-repack.c
@@ -0,0 +1,80 @@
+#include "config.h"
+#include "ntdb.h"
+#include "tap-interface.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include "logging.h"
+
+#define NUM_TESTS 1000
+
+static bool store_all(struct ntdb_context *ntdb)
+{
+	unsigned int i;
+	NTDB_DATA key = { (unsigned char *)&i, sizeof(i) };
+	NTDB_DATA dbuf = { (unsigned char *)&i, sizeof(i) };
+
+	for (i = 0; i < NUM_TESTS; i++) {
+		if (ntdb_store(ntdb, key, dbuf, NTDB_INSERT) != NTDB_SUCCESS)
+			return false;
+	}
+	return true;
+}
+
+static int mark_entry(struct ntdb_context *ntdb,
+		      NTDB_DATA key, NTDB_DATA data, bool found[])
+{
+	unsigned int num;
+
+	if (key.dsize != sizeof(num))
+		return -1;
+	memcpy(&num, key.dptr, key.dsize);
+	if (num >= NUM_TESTS)
+		return -1;
+	if (found[num])
+		return -1;
+	found[num] = true;
+	return 0;
+}
+
+static bool is_all_set(bool found[], unsigned int num)
+{
+	unsigned int i;
+
+	for (i = 0; i < num; i++)
+		if (!found[i])
+			return false;
+	return true;
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	bool found[NUM_TESTS];
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_CONVERT, NTDB_NOMMAP|NTDB_CONVERT
+	};
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 6 + 1);
+
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb = ntdb_open("run-93-repack.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		ok1(ntdb);
+		if (!ntdb)
+			break;
+
+		ok1(store_all(ntdb));
+
+		ok1(ntdb_repack(ntdb) == NTDB_SUCCESS);
+		memset(found, 0, sizeof(found));
+		ok1(ntdb_check(ntdb, NULL, NULL) == NTDB_SUCCESS);
+		ok1(ntdb_traverse(ntdb, mark_entry, found) == NUM_TESTS);
+		ok1(is_all_set(found, NUM_TESTS));
+		ntdb_close(ntdb);
+	}
+
+	ok1(tap_log_messages == 0);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/api-add-remove-flags.c b/lib/ntdb/test/api-add-remove-flags.c
new file mode 100644
index 0000000000..4888c32f06
--- /dev/null
+++ b/lib/ntdb/test/api-add-remove-flags.c
@@ -0,0 +1,89 @@
+#include "private.h" // for ntdb_context
+#include "ntdb.h"
+#include "tap-interface.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include "logging.h"
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_INTERNAL, NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_INTERNAL|NTDB_CONVERT, NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT };
+
+	plan_tests(87);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb = ntdb_open("run-add-remove-flags.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		ok1(ntdb);
+		if (!ntdb)
+			continue;
+
+		ok1(ntdb_get_flags(ntdb) == ntdb->flags);
+		tap_log_messages = 0;
+		ntdb_add_flag(ntdb, NTDB_NOLOCK);
+		if (flags[i] & NTDB_INTERNAL)
+			ok1(tap_log_messages == 1);
+		else {
+			ok1(tap_log_messages == 0);
+			ok1(ntdb_get_flags(ntdb) & NTDB_NOLOCK);
+		}
+
+		tap_log_messages = 0;
+		ntdb_add_flag(ntdb, NTDB_NOMMAP);
+		if (flags[i] & NTDB_INTERNAL)
+			ok1(tap_log_messages == 1);
+		else {
+			ok1(tap_log_messages == 0);
+			ok1(ntdb_get_flags(ntdb) & NTDB_NOMMAP);
+			ok1(ntdb->file->map_ptr == NULL);
+		}
+
+		tap_log_messages = 0;
+		ntdb_add_flag(ntdb, NTDB_NOSYNC);
+		if (flags[i] & NTDB_INTERNAL)
+			ok1(tap_log_messages == 1);
+		else {
+			ok1(tap_log_messages == 0);
+			ok1(ntdb_get_flags(ntdb) & NTDB_NOSYNC);
+		}
+
+		ok1(ntdb_get_flags(ntdb) == ntdb->flags);
+
+		tap_log_messages = 0;
+		ntdb_remove_flag(ntdb, NTDB_NOLOCK);
+		if (flags[i] & NTDB_INTERNAL)
+			ok1(tap_log_messages == 1);
+		else {
+			ok1(tap_log_messages == 0);
+			ok1(!(ntdb_get_flags(ntdb) & NTDB_NOLOCK));
+		}
+
+		tap_log_messages = 0;
+		ntdb_remove_flag(ntdb, NTDB_NOMMAP);
+		if (flags[i] & NTDB_INTERNAL)
+			ok1(tap_log_messages == 1);
+		else {
+			ok1(tap_log_messages == 0);
+			ok1(!(ntdb_get_flags(ntdb) & NTDB_NOMMAP));
+			ok1(ntdb->file->map_ptr != NULL);
+		}
+
+		tap_log_messages = 0;
+		ntdb_remove_flag(ntdb, NTDB_NOSYNC);
+		if (flags[i] & NTDB_INTERNAL)
+			ok1(tap_log_messages == 1);
+		else {
+			ok1(tap_log_messages == 0);
+			ok1(!(ntdb_get_flags(ntdb) & NTDB_NOSYNC));
+		}
+
+		ntdb_close(ntdb);
+	}
+
+	ok1(tap_log_messages == 0);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/api-check-callback.c b/lib/ntdb/test/api-check-callback.c
new file mode 100644
index 0000000000..f74f04b598
--- /dev/null
+++ b/lib/ntdb/test/api-check-callback.c
@@ -0,0 +1,86 @@
+#include "config.h"
+#include "ntdb.h"
+#include "tap-interface.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include "logging.h"
+
+#define NUM_RECORDS 1000
+
+static bool store_records(struct ntdb_context *ntdb)
+{
+	int i;
+	NTDB_DATA key = { (unsigned char *)&i, sizeof(i) };
+	NTDB_DATA data = { (unsigned char *)&i, sizeof(i) };
+
+	for (i = 0; i < NUM_RECORDS; i++)
+		if (ntdb_store(ntdb, key, data, NTDB_REPLACE) != 0)
+			return false;
+	return true;
+}
+
+static enum NTDB_ERROR check(NTDB_DATA key,
+			    NTDB_DATA data,
+			    bool *array)
+{
+	int val;
+
+	if (key.dsize != sizeof(val)) {
+		diag("Wrong key size: %u\n", key.dsize);
+		return NTDB_ERR_CORRUPT;
+	}
+
+	if (key.dsize != data.dsize
+	    || memcmp(key.dptr, data.dptr, sizeof(val)) != 0) {
+		diag("Key and data differ\n");
+		return NTDB_ERR_CORRUPT;
+	}
+
+	memcpy(&val, key.dptr, sizeof(val));
+	if (val >= NUM_RECORDS || val < 0) {
+		diag("check value %i\n", val);
+		return NTDB_ERR_CORRUPT;
+	}
+
+	if (array[val]) {
+		diag("Value %i already seen\n", val);
+		return NTDB_ERR_CORRUPT;
+	}
+
+	array[val] = true;
+	return NTDB_SUCCESS;
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i, j;
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_INTERNAL, NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_INTERNAL|NTDB_CONVERT, NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT };
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 4 + 1);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		bool array[NUM_RECORDS];
+
+		ntdb = ntdb_open("run-check-callback.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		ok1(ntdb);
+		if (!ntdb)
+			continue;
+
+		ok1(store_records(ntdb));
+		for (j = 0; j < NUM_RECORDS; j++)
+			array[j] = false;
+		ok1(ntdb_check(ntdb, check, array) == NTDB_SUCCESS);
+		for (j = 0; j < NUM_RECORDS; j++)
+			if (!array[j])
+				break;
+		ok1(j == NUM_RECORDS);
+		ntdb_close(ntdb);
+	}
+
+	ok1(tap_log_messages == 0);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/api-firstkey-nextkey.c b/lib/ntdb/test/api-firstkey-nextkey.c
new file mode 100644
index 0000000000..da1a68043b
--- /dev/null
+++ b/lib/ntdb/test/api-firstkey-nextkey.c
@@ -0,0 +1,159 @@
+#include "config.h"
+#include "ntdb.h"
+#include "tap-interface.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include "logging.h"
+
+#define NUM_RECORDS 1000
+
+static bool store_records(struct ntdb_context *ntdb)
+{
+	int i;
+	NTDB_DATA key = { (unsigned char *)&i, sizeof(i) };
+	NTDB_DATA data = { (unsigned char *)&i, sizeof(i) };
+
+	for (i = 0; i < NUM_RECORDS; i++)
+		if (ntdb_store(ntdb, key, data, NTDB_REPLACE) != 0)
+			return false;
+	return true;
+}
+
+struct trav_data {
+	unsigned int records[NUM_RECORDS];
+	unsigned int calls;
+};
+
+static int trav(struct ntdb_context *ntdb, NTDB_DATA key, NTDB_DATA dbuf, void *p)
+{
+	struct trav_data *td = p;
+	int val;
+
+	memcpy(&val, dbuf.dptr, dbuf.dsize);
+	td->records[td->calls++] = val;
+	return 0;
+}
+
+/* Since ntdb_nextkey frees dptr, we need to clone it. */
+static NTDB_DATA dup_key(NTDB_DATA key)
+{
+	void *p = malloc(key.dsize);
+	memcpy(p, key.dptr, key.dsize);
+	key.dptr = p;
+	return key;
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i, j;
+	int num;
+	struct trav_data td;
+	NTDB_DATA k;
+	struct ntdb_context *ntdb;
+	union ntdb_attribute seed_attr;
+	enum NTDB_ERROR ecode;
+	int flags[] = { NTDB_INTERNAL, NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_INTERNAL|NTDB_CONVERT, NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT };
+
+	seed_attr.base.attr = NTDB_ATTRIBUTE_SEED;
+	seed_attr.base.next = &tap_log_attr;
+	seed_attr.seed.seed = 6334326220117065685ULL;
+
+	plan_tests(sizeof(flags) / sizeof(flags[0])
+		   * (NUM_RECORDS*6 + (NUM_RECORDS-1)*3 + 22) + 1);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb = ntdb_open("api-firstkey-nextkey.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600,
+			       &seed_attr);
+		ok1(ntdb);
+		if (!ntdb)
+			continue;
+
+		ok1(ntdb_firstkey(ntdb, &k) == NTDB_ERR_NOEXIST);
+
+		/* One entry... */
+		k.dptr = (unsigned char *)&num;
+		k.dsize = sizeof(num);
+		num = 0;
+		ok1(ntdb_store(ntdb, k, k, NTDB_INSERT) == 0);
+		ok1(ntdb_firstkey(ntdb, &k) == NTDB_SUCCESS);
+		ok1(k.dsize == sizeof(num));
+		ok1(memcmp(k.dptr, &num, sizeof(num)) == 0);
+		ok1(ntdb_nextkey(ntdb, &k) == NTDB_ERR_NOEXIST);
+
+		/* Two entries. */
+		k.dptr = (unsigned char *)&num;
+		k.dsize = sizeof(num);
+		num = 1;
+		ok1(ntdb_store(ntdb, k, k, NTDB_INSERT) == 0);
+		ok1(ntdb_firstkey(ntdb, &k) == NTDB_SUCCESS);
+		ok1(k.dsize == sizeof(num));
+		memcpy(&num, k.dptr, sizeof(num));
+		ok1(num == 0 || num == 1);
+		ok1(ntdb_nextkey(ntdb, &k) == NTDB_SUCCESS);
+		ok1(k.dsize == sizeof(j));
+		memcpy(&j, k.dptr, sizeof(j));
+		ok1(j == 0 || j == 1);
+		ok1(j != num);
+		ok1(ntdb_nextkey(ntdb, &k) == NTDB_ERR_NOEXIST);
+
+		/* Clean up. */
+		k.dptr = (unsigned char *)&num;
+		k.dsize = sizeof(num);
+		num = 0;
+		ok1(ntdb_delete(ntdb, k) == 0);
+		num = 1;
+		ok1(ntdb_delete(ntdb, k) == 0);
+
+		/* Now lots of records. */
+		ok1(store_records(ntdb));
+		td.calls = 0;
+
+		num = ntdb_traverse(ntdb, trav, &td);
+		ok1(num == NUM_RECORDS);
+		ok1(td.calls == NUM_RECORDS);
+
+		/* Simple loop should match ntdb_traverse */
+		for (j = 0, ecode = ntdb_firstkey(ntdb, &k); j < td.calls; j++) {
+			int val;
+
+			ok1(ecode == NTDB_SUCCESS);
+			ok1(k.dsize == sizeof(val));
+			memcpy(&val, k.dptr, k.dsize);
+			ok1(td.records[j] == val);
+			ecode = ntdb_nextkey(ntdb, &k);
+		}
+
+		/* But arbitrary orderings should work too. */
+		for (j = td.calls-1; j > 0; j--) {
+			k.dptr = (unsigned char *)&td.records[j-1];
+			k.dsize = sizeof(td.records[j-1]);
+			k = dup_key(k);
+			ok1(ntdb_nextkey(ntdb, &k) == NTDB_SUCCESS);
+			ok1(k.dsize == sizeof(td.records[j]));
+			ok1(memcmp(k.dptr, &td.records[j], k.dsize) == 0);
+			free(k.dptr);
+		}
+
+		/* Even delete should work. */
+		for (j = 0, ecode = ntdb_firstkey(ntdb, &k);
+		     ecode != NTDB_ERR_NOEXIST;
+		     j++) {
+			ok1(ecode == NTDB_SUCCESS);
+			ok1(k.dsize == 4);
+			ok1(ntdb_delete(ntdb, k) == 0);
+			ecode = ntdb_nextkey(ntdb, &k);
+		}
+
+		diag("delete using first/nextkey gave %u of %u records",
+		     j, NUM_RECORDS);
+		ok1(j == NUM_RECORDS);
+		ntdb_close(ntdb);
+	}
+
+	ok1(tap_log_messages == 0);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/api-fork-test.c b/lib/ntdb/test/api-fork-test.c
new file mode 100644
index 0000000000..57bd686282
--- /dev/null
+++ b/lib/ntdb/test/api-fork-test.c
@@ -0,0 +1,179 @@
+/* Test forking while holding lock.
+ *
+ * There are only five ways to do this currently:
+ * (1) grab a ntdb_chainlock, then fork.
+ * (2) grab a ntdb_lockall, then fork.
+ * (3) grab a ntdb_lockall_read, then fork.
+ * (4) start a transaction, then fork.
+ * (5) fork from inside a ntdb_parse() callback.
+ *
+ * Note that we don't hold a lock across ntdb_traverse callbacks, so
+ * that doesn't matter.
+ */
+#include "config.h"
+#include "ntdb.h"
+#include "tap-interface.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include "logging.h"
+
+static enum NTDB_ERROR fork_in_parse(NTDB_DATA key, NTDB_DATA data,
+				    struct ntdb_context *ntdb)
+{
+	int status;
+
+	if (fork() == 0) {
+		/* We expect this to fail. */
+		if (ntdb_store(ntdb, key, data, NTDB_REPLACE) != NTDB_ERR_LOCK)
+			exit(1);
+
+		if (ntdb_fetch(ntdb, key, &data) != NTDB_ERR_LOCK)
+			exit(1);
+
+		if (tap_log_messages != 2)
+			exit(2);
+
+		ntdb_close(ntdb);
+		if (tap_log_messages != 2)
+			exit(3);
+		exit(0);
+	}
+	wait(&status);
+	ok1(WIFEXITED(status) && WEXITSTATUS(status) == 0);
+	return NTDB_SUCCESS;
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_CONVERT, NTDB_NOMMAP|NTDB_CONVERT };
+	NTDB_DATA key = ntdb_mkdata("key", 3);
+	NTDB_DATA data = ntdb_mkdata("data", 4);
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 14);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		int status;
+
+		tap_log_messages = 0;
+
+		ntdb = ntdb_open("run-fork-test.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		if (!ok1(ntdb))
+			continue;
+
+		/* Put a record in here. */
+		ok1(ntdb_store(ntdb, key, data, NTDB_REPLACE) == NTDB_SUCCESS);
+
+		ok1(ntdb_chainlock(ntdb, key) == NTDB_SUCCESS);
+		if (fork() == 0) {
+			/* We expect this to fail. */
+			if (ntdb_store(ntdb, key, data, NTDB_REPLACE) != NTDB_ERR_LOCK)
+				return 1;
+
+			if (ntdb_fetch(ntdb, key, &data) != NTDB_ERR_LOCK)
+				return 1;
+
+			if (tap_log_messages != 2)
+				return 2;
+
+			ntdb_chainunlock(ntdb, key);
+			if (tap_log_messages != 3)
+				return 3;
+			ntdb_close(ntdb);
+			if (tap_log_messages != 3)
+				return 4;
+			return 0;
+		}
+		wait(&status);
+		ok1(WIFEXITED(status) && WEXITSTATUS(status) == 0);
+		ntdb_chainunlock(ntdb, key);
+
+		ok1(ntdb_lockall(ntdb) == NTDB_SUCCESS);
+		if (fork() == 0) {
+			/* We expect this to fail. */
+			if (ntdb_store(ntdb, key, data, NTDB_REPLACE) != NTDB_ERR_LOCK)
+				return 1;
+
+			if (ntdb_fetch(ntdb, key, &data) != NTDB_ERR_LOCK)
+				return 1;
+
+			if (tap_log_messages != 2)
+				return 2;
+
+			ntdb_unlockall(ntdb);
+			if (tap_log_messages != 2)
+				return 3;
+			ntdb_close(ntdb);
+			if (tap_log_messages != 2)
+				return 4;
+			return 0;
+		}
+		wait(&status);
+		ok1(WIFEXITED(status) && WEXITSTATUS(status) == 0);
+		ntdb_unlockall(ntdb);
+
+		ok1(ntdb_lockall_read(ntdb) == NTDB_SUCCESS);
+		if (fork() == 0) {
+			/* We expect this to fail. */
+			/* This would always fail anyway... */
+			if (ntdb_store(ntdb, key, data, NTDB_REPLACE) != NTDB_ERR_LOCK)
+				return 1;
+
+			if (ntdb_fetch(ntdb, key, &data) != NTDB_ERR_LOCK)
+				return 1;
+
+			if (tap_log_messages != 2)
+				return 2;
+
+			ntdb_unlockall_read(ntdb);
+			if (tap_log_messages != 2)
+				return 3;
+			ntdb_close(ntdb);
+			if (tap_log_messages != 2)
+				return 4;
+			return 0;
+		}
+		wait(&status);
+		ok1(WIFEXITED(status) && WEXITSTATUS(status) == 0);
+		ntdb_unlockall_read(ntdb);
+
+		ok1(ntdb_transaction_start(ntdb) == NTDB_SUCCESS);
+		/* If transactions is empty, noop "commit" succeeds. */
+		ok1(ntdb_delete(ntdb, key) == NTDB_SUCCESS);
+		if (fork() == 0) {
+			/* We expect this to fail. */
+			if (ntdb_store(ntdb, key, data, NTDB_REPLACE) != NTDB_ERR_LOCK)
+				return 1;
+
+			if (ntdb_fetch(ntdb, key, &data) != NTDB_ERR_LOCK)
+				return 1;
+
+			if (tap_log_messages != 2)
+				return 2;
+
+			if (ntdb_transaction_commit(ntdb) != NTDB_ERR_LOCK)
+				return 3;
+
+			ntdb_close(ntdb);
+			if (tap_log_messages < 3)
+				return 4;
+			return 0;
+		}
+		wait(&status);
+		ok1(WIFEXITED(status) && WEXITSTATUS(status) == 0);
+		ntdb_transaction_cancel(ntdb);
+
+		ok1(ntdb_parse_record(ntdb, key, fork_in_parse, ntdb)
+		    == NTDB_SUCCESS);
+		ntdb_close(ntdb);
+		ok1(tap_log_messages == 0);
+	}
+	return exit_status();
+}
diff --git a/lib/ntdb/test/api-locktimeout.c b/lib/ntdb/test/api-locktimeout.c
new file mode 100644
index 0000000000..cafe067d0b
--- /dev/null
+++ b/lib/ntdb/test/api-locktimeout.c
@@ -0,0 +1,193 @@
+#include "config.h"
+#include "ntdb.h"
+#include "tap-interface.h"
+#include "system/wait.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <errno.h>
+#include "logging.h"
+#include "external-agent.h"
+
+#undef alarm
+#define alarm fast_alarm
+
+/* Speed things up by doing things in milliseconds. */
+static unsigned int fast_alarm(unsigned int milli_seconds)
+{
+	struct itimerval it;
+
+	it.it_interval.tv_sec = it.it_interval.tv_usec = 0;
+	it.it_value.tv_sec = milli_seconds / 1000;
+	it.it_value.tv_usec = milli_seconds * 1000;
+	setitimer(ITIMER_REAL, &it, NULL);
+	return 0;
+}
+
+#define CatchSignal(sig, handler) signal((sig), (handler))
+
+static void do_nothing(int signum)
+{
+}
+
+/* This example code is taken from SAMBA, so try not to change it. */
+static struct flock flock_struct;
+
+/* Return a value which is none of v1, v2 or v3. */
+static inline short int invalid_value(short int v1, short int v2, short int v3)
+{
+	short int try = (v1+v2+v3)^((v1+v2+v3) << 16);
+	while (try == v1 || try == v2 || try == v3)
+		try++;
+	return try;
+}
+
+/* We invalidate in as many ways as we can, so the OS rejects it */
+static void invalidate_flock_struct(int signum)
+{
+	flock_struct.l_type = invalid_value(F_RDLCK, F_WRLCK, F_UNLCK);
+	flock_struct.l_whence = invalid_value(SEEK_SET, SEEK_CUR, SEEK_END);
+	flock_struct.l_start = -1;
+	/* A large negative. */
+	flock_struct.l_len = (((off_t)1 << (sizeof(off_t)*CHAR_BIT - 1)) + 1);
+}
+
+static int timeout_lock(int fd, int rw, off_t off, off_t len, bool waitflag,
+			void *_timeout)
+{
+	int ret, saved_errno = errno;
+	unsigned int timeout = *(unsigned int *)_timeout;
+
+	flock_struct.l_type = rw;
+	flock_struct.l_whence = SEEK_SET;
+	flock_struct.l_start = off;
+	flock_struct.l_len = len;
+
+	CatchSignal(SIGALRM, invalidate_flock_struct);
+	alarm(timeout);
+
+	for (;;) {
+		if (waitflag)
+			ret = fcntl(fd, F_SETLKW, &flock_struct);
+		else
+			ret = fcntl(fd, F_SETLK, &flock_struct);
+
+		if (ret == 0)
+			break;
+
+		/* Not signalled?  Something else went wrong. */
+		if (flock_struct.l_len == len) {
+			if (errno == EAGAIN || errno == EINTR)
+				continue;
+			saved_errno = errno;
+			break;
+		} else {
+			saved_errno = EINTR;
+			break;
+		}
+	}
+
+	alarm(0);
+	errno = saved_errno;
+	return ret;
+}
+
+static int ntdb_chainlock_with_timeout_internal(struct ntdb_context *ntdb,
+					       NTDB_DATA key,
+					       unsigned int timeout,
+					       int rw_type)
+{
+	union ntdb_attribute locking;
+	enum NTDB_ERROR ecode;
+
+	if (timeout) {
+		locking.base.attr = NTDB_ATTRIBUTE_FLOCK;
+		ecode = ntdb_get_attribute(ntdb, &locking);
+		if (ecode != NTDB_SUCCESS)
+			return ecode;
+
+		/* Replace locking function with our own. */
+		locking.flock.data = &timeout;
+		locking.flock.lock = timeout_lock;
+
+		ecode = ntdb_set_attribute(ntdb, &locking);
+		if (ecode != NTDB_SUCCESS)
+			return ecode;
+	}
+	if (rw_type == F_RDLCK)
+		ecode = ntdb_chainlock_read(ntdb, key);
+	else
+		ecode = ntdb_chainlock(ntdb, key);
+
+	if (timeout) {
+		ntdb_unset_attribute(ntdb, NTDB_ATTRIBUTE_FLOCK);
+	}
+	return ecode;
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_context *ntdb;
+	NTDB_DATA key = ntdb_mkdata("hello", 5);
+	int flags[] = { NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_CONVERT, NTDB_NOMMAP|NTDB_CONVERT };
+	struct agent *agent;
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 15);
+
+	agent = prepare_external_agent();
+
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		enum NTDB_ERROR ecode;
+		ntdb = ntdb_open("run-locktimeout.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		if (!ok1(ntdb))
+			break;
+
+		/* Simple cases: should succeed. */
+		ecode = ntdb_chainlock_with_timeout_internal(ntdb, key, 20,
+							    F_RDLCK);
+		ok1(ecode == NTDB_SUCCESS);
+		ok1(tap_log_messages == 0);
+
+		ntdb_chainunlock_read(ntdb, key);
+		ok1(tap_log_messages == 0);
+
+		ecode = ntdb_chainlock_with_timeout_internal(ntdb, key, 20,
+							    F_WRLCK);
+		ok1(ecode == NTDB_SUCCESS);
+		ok1(tap_log_messages == 0);
+
+		ntdb_chainunlock(ntdb, key);
+		ok1(tap_log_messages == 0);
+
+		/* OK, get agent to start transaction, then we should time out. */
+		ok1(external_agent_operation(agent, OPEN, "run-locktimeout.ntdb")
+		    == SUCCESS);
+		ok1(external_agent_operation(agent, TRANSACTION_START, "")
+		    == SUCCESS);
+		ecode = ntdb_chainlock_with_timeout_internal(ntdb, key, 20,
+							    F_WRLCK);
+		ok1(ecode == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 0);
+
+		/* Even if we get a different signal, should be fine. */
+		CatchSignal(SIGUSR1, do_nothing);
+		external_agent_operation(agent, SEND_SIGNAL, "");
+		ecode = ntdb_chainlock_with_timeout_internal(ntdb, key, 20,
+							    F_WRLCK);
+		ok1(ecode == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 0);
+
+		ok1(external_agent_operation(agent, TRANSACTION_COMMIT, "")
+		    == SUCCESS);
+		ok1(external_agent_operation(agent, CLOSE, "")
+		    == SUCCESS);
+		ntdb_close(ntdb);
+	}
+	free_external_agent(agent);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/api-missing-entries.c b/lib/ntdb/test/api-missing-entries.c
new file mode 100644
index 0000000000..1c8064f945
--- /dev/null
+++ b/lib/ntdb/test/api-missing-entries.c
@@ -0,0 +1,44 @@
+/* Another test revealed that we lost an entry.  This reproduces it. */
+#include "config.h"
+#include "ntdb.h"
+#include <ccan/hash/hash.h>
+#include "tap-interface.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include "logging.h"
+
+#define NUM_RECORDS 1189
+
+/* We use the same seed which we saw this failure on. */
+static uint64_t failhash(const void *key, size_t len, uint64_t seed, void *p)
+{
+	seed = 699537674708983027ULL;
+	return hash64_stable((const unsigned char *)key, len, seed);
+}
+
+int main(int argc, char *argv[])
+{
+	int i;
+	struct ntdb_context *ntdb;
+	NTDB_DATA key = { (unsigned char *)&i, sizeof(i) };
+	NTDB_DATA data = { (unsigned char *)&i, sizeof(i) };
+	union ntdb_attribute hattr = { .hash = { .base = { NTDB_ATTRIBUTE_HASH },
+						.fn = failhash } };
+
+	hattr.base.next = &tap_log_attr;
+	plan_tests(1 + NUM_RECORDS + 2);
+
+	ntdb = ntdb_open("run-missing-entries.ntdb", NTDB_INTERNAL,
+		       O_RDWR|O_CREAT|O_TRUNC, 0600, &hattr);
+	if (ok1(ntdb)) {
+		for (i = 0; i < NUM_RECORDS; i++) {
+			ok1(ntdb_store(ntdb, key, data, NTDB_REPLACE) == 0);
+		}
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+		ntdb_close(ntdb);
+	}
+
+	ok1(tap_log_messages == 0);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/api-open-multiple-times.c b/lib/ntdb/test/api-open-multiple-times.c
new file mode 100644
index 0000000000..70bad00568
--- /dev/null
+++ b/lib/ntdb/test/api-open-multiple-times.c
@@ -0,0 +1,83 @@
+#include "config.h"
+#include "ntdb.h"
+#include "tap-interface.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include "logging.h"
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_context *ntdb, *ntdb2;
+	NTDB_DATA key = { (unsigned char *)&i, sizeof(i) };
+	NTDB_DATA data = { (unsigned char *)&i, sizeof(i) };
+	NTDB_DATA d = { NULL, 0 }; /* Bogus GCC warning */
+	int flags[] = { NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_CONVERT, NTDB_NOMMAP|NTDB_CONVERT };
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 28);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb = ntdb_open("run-open-multiple-times.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		ok1(ntdb);
+		if (!ntdb)
+			continue;
+
+		ntdb2 = ntdb_open("run-open-multiple-times.ntdb", flags[i],
+				O_RDWR|O_CREAT, 0600, &tap_log_attr);
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+		ok1(ntdb_check(ntdb2, NULL, NULL) == 0);
+
+		/* Store in one, fetch in the other. */
+		ok1(ntdb_store(ntdb, key, data, NTDB_REPLACE) == 0);
+		ok1(ntdb_fetch(ntdb2, key, &d) == NTDB_SUCCESS);
+		ok1(ntdb_deq(d, data));
+		free(d.dptr);
+
+		/* Vice versa, with delete. */
+		ok1(ntdb_delete(ntdb2, key) == 0);
+		ok1(ntdb_fetch(ntdb, key, &d) == NTDB_ERR_NOEXIST);
+
+		/* OK, now close first one, check second still good. */
+		ok1(ntdb_close(ntdb) == 0);
+
+		ok1(ntdb_store(ntdb2, key, data, NTDB_REPLACE) == 0);
+		ok1(ntdb_fetch(ntdb2, key, &d) == NTDB_SUCCESS);
+		ok1(ntdb_deq(d, data));
+		free(d.dptr);
+
+		/* Reopen */
+		ntdb = ntdb_open("run-open-multiple-times.ntdb", flags[i],
+			       O_RDWR|O_CREAT, 0600, &tap_log_attr);
+		ok1(ntdb);
+
+		ok1(ntdb_transaction_start(ntdb2) == 0);
+
+		/* Anything in the other one should fail. */
+		ok1(ntdb_fetch(ntdb, key, &d) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 1);
+		ok1(ntdb_store(ntdb, key, data, NTDB_REPLACE) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 2);
+		ok1(ntdb_transaction_start(ntdb) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 3);
+		ok1(ntdb_chainlock(ntdb, key) == NTDB_ERR_LOCK);
+		ok1(tap_log_messages == 4);
+
+		/* Transaciton should work as normal. */
+		ok1(ntdb_store(ntdb2, key, data, NTDB_REPLACE) == NTDB_SUCCESS);
+
+		/* Now... try closing with locks held. */
+		ok1(ntdb_close(ntdb2) == 0);
+
+		ok1(ntdb_fetch(ntdb, key, &d) == NTDB_SUCCESS);
+		ok1(ntdb_deq(d, data));
+		free(d.dptr);
+		ok1(ntdb_close(ntdb) == 0);
+		ok1(tap_log_messages == 4);
+		tap_log_messages = 0;
+	}
+
+	return exit_status();
+}
diff --git a/lib/ntdb/test/api-record-expand.c b/lib/ntdb/test/api-record-expand.c
new file mode 100644
index 0000000000..cea5a10bfb
--- /dev/null
+++ b/lib/ntdb/test/api-record-expand.c
@@ -0,0 +1,51 @@
+#include "config.h"
+#include "ntdb.h"
+#include "tap-interface.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include "logging.h"
+
+#define MAX_SIZE 10000
+#define SIZE_STEP 131
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_INTERNAL, NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_INTERNAL|NTDB_CONVERT, NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT };
+	NTDB_DATA key = ntdb_mkdata("key", 3);
+	NTDB_DATA data;
+
+	data.dptr = malloc(MAX_SIZE);
+	memset(data.dptr, 0x24, MAX_SIZE);
+
+	plan_tests(sizeof(flags) / sizeof(flags[0])
+		   * (3 + (1 + (MAX_SIZE/SIZE_STEP)) * 2) + 1);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb = ntdb_open("run-record-expand.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		ok1(ntdb);
+		if (!ntdb)
+			continue;
+
+		data.dsize = 0;
+		ok1(ntdb_store(ntdb, key, data, NTDB_INSERT) == 0);
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+		for (data.dsize = 0;
+		     data.dsize < MAX_SIZE;
+		     data.dsize += SIZE_STEP) {
+			memset(data.dptr, data.dsize, data.dsize);
+			ok1(ntdb_store(ntdb, key, data, NTDB_MODIFY) == 0);
+			ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+		}
+		ntdb_close(ntdb);
+	}
+	ok1(tap_log_messages == 0);
+	free(data.dptr);
+
+	return exit_status();
+}
diff --git a/lib/ntdb/test/api-simple-delete.c b/lib/ntdb/test/api-simple-delete.c
new file mode 100644
index 0000000000..2b20e199ee
--- /dev/null
+++ b/lib/ntdb/test/api-simple-delete.c
@@ -0,0 +1,39 @@
+#include "config.h"
+#include "ntdb.h"
+#include "tap-interface.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include "logging.h"
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_INTERNAL, NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_INTERNAL|NTDB_CONVERT, NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT };
+	NTDB_DATA key = ntdb_mkdata("key", 3);
+	NTDB_DATA data = ntdb_mkdata("data", 4);
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 7 + 1);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb = ntdb_open("run-simple-delete.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		ok1(ntdb);
+		if (ntdb) {
+			/* Delete should fail. */
+			ok1(ntdb_delete(ntdb, key) == NTDB_ERR_NOEXIST);
+			ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+			/* Insert should succeed. */
+			ok1(ntdb_store(ntdb, key, data, NTDB_INSERT) == 0);
+			ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+			/* Delete should now work. */
+			ok1(ntdb_delete(ntdb, key) == 0);
+			ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+			ntdb_close(ntdb);
+		}
+	}
+	ok1(tap_log_messages == 0);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/api-summary.c b/lib/ntdb/test/api-summary.c
new file mode 100644
index 0000000000..8060ef29be
--- /dev/null
+++ b/lib/ntdb/test/api-summary.c
@@ -0,0 +1,58 @@
+#include "config.h"
+#include "ntdb.h"
+#include "tap-interface.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include "logging.h"
+
+int main(int argc, char *argv[])
+{
+	unsigned int i, j;
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_INTERNAL, NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_INTERNAL|NTDB_CONVERT, NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT };
+	NTDB_DATA key = { (unsigned char *)&j, sizeof(j) };
+	NTDB_DATA data = { (unsigned char *)&j, sizeof(j) };
+	char *summary;
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * (1 + 2 * 5) + 1);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb = ntdb_open("run-summary.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		ok1(ntdb);
+		if (!ntdb)
+			continue;
+
+		/* Put some stuff in there. */
+		for (j = 0; j < 500; j++) {
+			/* Make sure padding varies to we get some graphs! */
+			data.dsize = j % (sizeof(j) + 1);
+			if (ntdb_store(ntdb, key, data, NTDB_REPLACE) != 0)
+				fail("Storing in ntdb");
+		}
+
+		for (j = 0;
+		     j <= NTDB_SUMMARY_HISTOGRAMS;
+		     j += NTDB_SUMMARY_HISTOGRAMS) {
+			ok1(ntdb_summary(ntdb, j, &summary) == NTDB_SUCCESS);
+			ok1(strstr(summary, "Number of records: 500\n"));
+			ok1(strstr(summary, "Smallest/average/largest keys: 4/4/4\n"));
+			ok1(strstr(summary, "Smallest/average/largest data: 0/2/4\n"));
+			if (j == NTDB_SUMMARY_HISTOGRAMS) {
+				ok1(strstr(summary, "|")
+				    && strstr(summary, "*"));
+			} else {
+				ok1(!strstr(summary, "|")
+				    && !strstr(summary, "*"));
+			}
+			free(summary);
+		}
+		ntdb_close(ntdb);
+	}
+
+	ok1(tap_log_messages == 0);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/external-agent.c b/lib/ntdb/test/external-agent.c
new file mode 100644
index 0000000000..098d0cb595
--- /dev/null
+++ b/lib/ntdb/test/external-agent.c
@@ -0,0 +1,252 @@
+#include "external-agent.h"
+#include "logging.h"
+#include "lock-tracking.h"
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+#include <ccan/err/err.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <limits.h>
+#include <string.h>
+#include <errno.h>
+#include "tap-interface.h"
+#include <stdio.h>
+#include <stdarg.h>
+
+static struct ntdb_context *ntdb;
+
+void (*external_agent_free)(void *) = free;
+
+static enum NTDB_ERROR clear_if_first(int fd, void *arg)
+{
+/* We hold a lock offset 4 always, so we can tell if anyone is holding it.
+ * (This is compatible with tdb's TDB_CLEAR_IF_FIRST flag).  */
+	struct flock fl;
+
+	fl.l_type = F_WRLCK;
+	fl.l_whence = SEEK_SET;
+	fl.l_start = 4;
+	fl.l_len = 1;
+
+	if (fcntl(fd, F_SETLK, &fl) == 0) {
+		/* We must be first ones to open it! */
+		diag("agent truncating file!");
+		if (ftruncate(fd, 0) != 0) {
+			return NTDB_ERR_IO;
+		}
+	}
+	fl.l_type = F_RDLCK;
+	if (fcntl(fd, F_SETLKW, &fl) != 0) {
+		return NTDB_ERR_IO;
+	}
+	return NTDB_SUCCESS;
+}
+
+static enum agent_return do_operation(enum operation op, const char *name)
+{
+	NTDB_DATA k;
+	enum agent_return ret;
+	NTDB_DATA data;
+	enum NTDB_ERROR ecode;
+	union ntdb_attribute cif;
+
+	if (op != OPEN && op != OPEN_WITH_HOOK && !ntdb) {
+		diag("external: No ntdb open!");
+		return OTHER_FAILURE;
+	}
+
+	diag("external: %s", operation_name(op));
+
+	k = ntdb_mkdata(name, strlen(name));
+
+	locking_would_block = 0;
+	switch (op) {
+	case OPEN:
+		if (ntdb) {
+			diag("Already have ntdb %s open", ntdb_name(ntdb));
+			return OTHER_FAILURE;
+		}
+		ntdb = ntdb_open(name, NTDB_DEFAULT, O_RDWR, 0, &tap_log_attr);
+		if (!ntdb) {
+			if (!locking_would_block)
+				diag("Opening ntdb gave %s", strerror(errno));
+			forget_locking();
+			ret = OTHER_FAILURE;
+		} else
+			ret = SUCCESS;
+		break;
+	case OPEN_WITH_HOOK:
+		if (ntdb) {
+			diag("Already have ntdb %s open", ntdb_name(ntdb));
+			return OTHER_FAILURE;
+		}
+		cif.openhook.base.attr = NTDB_ATTRIBUTE_OPENHOOK;
+		cif.openhook.base.next = &tap_log_attr;
+		cif.openhook.fn = clear_if_first;
+		ntdb = ntdb_open(name, NTDB_DEFAULT, O_RDWR, 0, &cif);
+		if (!ntdb) {
+			if (!locking_would_block)
+				diag("Opening ntdb gave %s", strerror(errno));
+			forget_locking();
+			ret = OTHER_FAILURE;
+		} else
+			ret = SUCCESS;
+		break;
+	case FETCH:
+		ecode = ntdb_fetch(ntdb, k, &data);
+		if (ecode == NTDB_ERR_NOEXIST) {
+			ret = FAILED;
+		} else if (ecode < 0) {
+			ret = OTHER_FAILURE;
+		} else if (!ntdb_deq(data, k)) {
+			ret = OTHER_FAILURE;
+			external_agent_free(data.dptr);
+		} else {
+			ret = SUCCESS;
+			external_agent_free(data.dptr);
+		}
+		break;
+	case STORE:
+		ret = ntdb_store(ntdb, k, k, 0) == 0 ? SUCCESS : OTHER_FAILURE;
+		break;
+	case TRANSACTION_START:
+		ret = ntdb_transaction_start(ntdb) == 0 ? SUCCESS : OTHER_FAILURE;
+		break;
+	case TRANSACTION_COMMIT:
+		ret = ntdb_transaction_commit(ntdb)==0 ? SUCCESS : OTHER_FAILURE;
+		break;
+	case NEEDS_RECOVERY:
+		ret = external_agent_needs_rec(ntdb);
+		break;
+	case CHECK:
+		ret = ntdb_check(ntdb, NULL, NULL) == 0 ? SUCCESS : OTHER_FAILURE;
+		break;
+	case CLOSE:
+		ret = ntdb_close(ntdb) == 0 ? SUCCESS : OTHER_FAILURE;
+		ntdb = NULL;
+		break;
+	case SEND_SIGNAL:
+		/* We do this async */
+		ret = SUCCESS;
+		break;
+	default:
+		ret = OTHER_FAILURE;
+	}
+
+	if (locking_would_block)
+		ret = WOULD_HAVE_BLOCKED;
+
+	return ret;
+}
+
+struct agent {
+	int cmdfd, responsefd;
+};
+
+/* Do this before doing any ntdb stuff.  Return handle, or NULL. */
+struct agent *prepare_external_agent(void)
+{
+	int pid, ret;
+	int command[2], response[2];
+	char name[1+PATH_MAX];
+
+	if (pipe(command) != 0 || pipe(response) != 0)
+		return NULL;
+
+	pid = fork();
+	if (pid < 0)
+		return NULL;
+
+	if (pid != 0) {
+		struct agent *agent = malloc(sizeof(*agent));
+
+		close(command[0]);
+		close(response[1]);
+		agent->cmdfd = command[1];
+		agent->responsefd = response[0];
+		return agent;
+	}
+
+	close(command[1]);
+	close(response[0]);
+
+	/* We want to fail, not block. */
+	nonblocking_locks = true;
+	log_prefix = "external: ";
+	while ((ret = read(command[0], name, sizeof(name))) > 0) {
+		enum agent_return result;
+
+		result = do_operation(name[0], name+1);
+		if (write(response[1], &result, sizeof(result))
+		    != sizeof(result))
+			err(1, "Writing response");
+		if (name[0] == SEND_SIGNAL) {
+			struct timeval ten_ms;
+			ten_ms.tv_sec = 0;
+			ten_ms.tv_usec = 10000;
+			select(0, NULL, NULL, NULL, &ten_ms);
+			kill(getppid(), SIGUSR1);
+		}
+	}
+	exit(0);
+}
+
+/* Ask the external agent to try to do an operation. */
+enum agent_return external_agent_operation(struct agent *agent,
+					   enum operation op,
+					   const char *name)
+{
+	enum agent_return res;
+	unsigned int len;
+	char *string;
+
+	if (!name)
+		name = "";
+	len = 1 + strlen(name) + 1;
+	string = malloc(len);
+
+	string[0] = op;
+	strcpy(string+1, name);
+
+	if (write(agent->cmdfd, string, len) != len
+	    || read(agent->responsefd, &res, sizeof(res)) != sizeof(res))
+		res = AGENT_DIED;
+
+	free(string);
+	return res;
+}
+
+const char *agent_return_name(enum agent_return ret)
+{
+	return ret == SUCCESS ? "SUCCESS"
+		: ret == WOULD_HAVE_BLOCKED ? "WOULD_HAVE_BLOCKED"
+		: ret == AGENT_DIED ? "AGENT_DIED"
+		: ret == FAILED ? "FAILED"
+		: ret == OTHER_FAILURE ? "OTHER_FAILURE"
+		: "**INVALID**";
+}
+
+const char *operation_name(enum operation op)
+{
+	switch (op) {
+	case OPEN: return "OPEN";
+	case OPEN_WITH_HOOK: return "OPEN_WITH_HOOK";
+	case FETCH: return "FETCH";
+	case STORE: return "STORE";
+	case CHECK: return "CHECK";
+	case TRANSACTION_START: return "TRANSACTION_START";
+	case TRANSACTION_COMMIT: return "TRANSACTION_COMMIT";
+	case NEEDS_RECOVERY: return "NEEDS_RECOVERY";
+	case SEND_SIGNAL: return "SEND_SIGNAL";
+	case CLOSE: return "CLOSE";
+	}
+	return "**INVALID**";
+}
+
+void free_external_agent(struct agent *agent)
+{
+	close(agent->cmdfd);
+	close(agent->responsefd);
+	free(agent);
+}
diff --git a/lib/ntdb/test/external-agent.h b/lib/ntdb/test/external-agent.h
new file mode 100644
index 0000000000..c6b83d5b49
--- /dev/null
+++ b/lib/ntdb/test/external-agent.h
@@ -0,0 +1,51 @@
+#ifndef NTDB_TEST_EXTERNAL_AGENT_H
+#define NTDB_TEST_EXTERNAL_AGENT_H
+
+/* For locking tests, we need a different process to try things at
+ * various times. */
+enum operation {
+	OPEN,
+	OPEN_WITH_HOOK,
+	FETCH,
+	STORE,
+	TRANSACTION_START,
+	TRANSACTION_COMMIT,
+	NEEDS_RECOVERY,
+	CHECK,
+	SEND_SIGNAL,
+	CLOSE,
+};
+
+/* Do this before doing any ntdb stuff.  Return handle, or -1. */
+struct agent *prepare_external_agent(void);
+
+enum agent_return {
+	SUCCESS,
+	WOULD_HAVE_BLOCKED,
+	AGENT_DIED,
+	FAILED, /* For fetch, or NEEDS_RECOVERY */
+	OTHER_FAILURE,
+};
+
+/* Ask the external agent to try to do an operation.
+ * name == ntdb name for OPEN/OPEN_WITH_CLEAR_IF_FIRST,
+ * record name for FETCH/STORE (store stores name as data too)
+ */
+enum agent_return external_agent_operation(struct agent *handle,
+					   enum operation op,
+					   const char *name);
+
+/* Hook into free() on ntdb_data in external agent. */
+extern void (*external_agent_free)(void *);
+
+/* Mapping enum -> string. */
+const char *agent_return_name(enum agent_return ret);
+const char *operation_name(enum operation op);
+
+void free_external_agent(struct agent *agent);
+
+/* Internal use: */
+struct ntdb_context;
+enum agent_return external_agent_needs_rec(struct ntdb_context *ntdb);
+
+#endif /* NTDB_TEST_EXTERNAL_AGENT_H */
diff --git a/lib/ntdb/test/failtest_helper.c b/lib/ntdb/test/failtest_helper.c
new file mode 100644
index 0000000000..cc110919c3
--- /dev/null
+++ b/lib/ntdb/test/failtest_helper.c
@@ -0,0 +1,96 @@
+#include "failtest_helper.h"
+#include "logging.h"
+#include <string.h>
+#include "tap-interface.h"
+
+bool failtest_suppress = false;
+
+/* FIXME: From ccan/str */
+static inline bool strends(const char *str, const char *postfix)
+{
+	if (strlen(str) < strlen(postfix))
+		return false;
+
+	return !strcmp(str + strlen(str) - strlen(postfix), postfix);
+}
+
+bool failmatch(const struct failtest_call *call,
+	       const char *file, int line, enum failtest_call_type type)
+{
+	return call->type == type
+		&& call->line == line
+		&& ((strcmp(call->file, file) == 0)
+		    || (strends(call->file, file)
+			&& (call->file[strlen(call->file) - strlen(file) - 1]
+			    == '/')));
+}
+
+static bool is_nonblocking_lock(const struct failtest_call *call)
+{
+	return call->type == FAILTEST_FCNTL && call->u.fcntl.cmd == F_SETLK;
+}
+
+static bool is_unlock(const struct failtest_call *call)
+{
+	return call->type == FAILTEST_FCNTL
+		&& call->u.fcntl.arg.fl.l_type == F_UNLCK;
+}
+
+bool exit_check_log(struct tlist_calls *history)
+{
+	const struct failtest_call *i;
+
+	tlist_for_each(history, i, list) {
+		if (!i->fail)
+			continue;
+		/* Failing the /dev/urandom open doesn't count: we fall back. */
+		if (failmatch(i, URANDOM_OPEN))
+			continue;
+
+		/* Similarly with read fail. */
+		if (failmatch(i, URANDOM_READ))
+			continue;
+
+		/* Initial allocation of ntdb doesn't log. */
+		if (failmatch(i, INITIAL_NTDB_MALLOC))
+			continue;
+
+		/* We don't block "failures" on non-blocking locks. */
+		if (is_nonblocking_lock(i))
+			continue;
+
+		if (!tap_log_messages)
+			diag("We didn't log for %s:%u", i->file, i->line);
+		return tap_log_messages != 0;
+	}
+	return true;
+}
+
+/* Some places we soldier on despite errors: only fail them once. */
+enum failtest_result
+block_repeat_failures(struct tlist_calls *history)
+{
+	const struct failtest_call *last;
+
+	last = tlist_tail(history, list);
+
+	if (failtest_suppress)
+		return FAIL_DONT_FAIL;
+
+	if (failmatch(last, INITIAL_NTDB_MALLOC)
+	    || failmatch(last, URANDOM_OPEN)
+	    || failmatch(last, URANDOM_READ)) {
+		return FAIL_PROBE;
+	}
+
+	/* We handle mmap failing, by falling back to read/write, so
+	 * don't try all possible paths. */
+	if (last->type == FAILTEST_MMAP)
+		return FAIL_PROBE;
+
+	/* Unlock or non-blocking lock is fail-once. */
+	if (is_unlock(last) || is_nonblocking_lock(last))
+		return FAIL_PROBE;
+
+	return FAIL_OK;
+}
diff --git a/lib/ntdb/test/failtest_helper.h b/lib/ntdb/test/failtest_helper.h
new file mode 100644
index 0000000000..e754636402
--- /dev/null
+++ b/lib/ntdb/test/failtest_helper.h
@@ -0,0 +1,19 @@
+#ifndef NTDB_TEST_FAILTEST_HELPER_H
+#define NTDB_TEST_FAILTEST_HELPER_H
+#include <ccan/failtest/failtest.h>
+#include <stdbool.h>
+
+/* FIXME: Check these! */
+#define INITIAL_NTDB_MALLOC	"open.c", 403, FAILTEST_MALLOC
+#define URANDOM_OPEN		"open.c", 62, FAILTEST_OPEN
+#define URANDOM_READ		"open.c", 42, FAILTEST_READ
+
+bool exit_check_log(struct tlist_calls *history);
+bool failmatch(const struct failtest_call *call,
+	       const char *file, int line, enum failtest_call_type type);
+enum failtest_result block_repeat_failures(struct tlist_calls *history);
+
+/* Set this to suppress failure. */
+extern bool failtest_suppress;
+
+#endif /* NTDB_TEST_LOGGING_H */
diff --git a/lib/ntdb/test/helpapi-external-agent.c b/lib/ntdb/test/helpapi-external-agent.c
new file mode 100644
index 0000000000..eb81399072
--- /dev/null
+++ b/lib/ntdb/test/helpapi-external-agent.c
@@ -0,0 +1,7 @@
+#include "external-agent.h"
+
+/* This isn't possible with via the ntdb API, but this makes it link. */
+enum agent_return external_agent_needs_rec(struct ntdb_context *ntdb)
+{
+	return FAILED;
+}
diff --git a/lib/ntdb/test/helprun-external-agent.c b/lib/ntdb/test/helprun-external-agent.c
new file mode 100644
index 0000000000..81a3fe881d
--- /dev/null
+++ b/lib/ntdb/test/helprun-external-agent.c
@@ -0,0 +1,7 @@
+#include "external-agent.h"
+#include "private.h"
+
+enum agent_return external_agent_needs_rec(struct ntdb_context *ntdb)
+{
+	return ntdb_needs_recovery(ntdb) ? SUCCESS : FAILED;
+}
diff --git a/lib/ntdb/test/helprun-layout.c b/lib/ntdb/test/helprun-layout.c
new file mode 100644
index 0000000000..c8f1fd03c4
--- /dev/null
+++ b/lib/ntdb/test/helprun-layout.c
@@ -0,0 +1,402 @@
+/* NTDB tools to create various canned database layouts. */
+#include "layout.h"
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+#include <ccan/err/err.h>
+#include "logging.h"
+
+struct ntdb_layout *new_ntdb_layout(void)
+{
+	struct ntdb_layout *layout = malloc(sizeof(*layout));
+	layout->num_elems = 0;
+	layout->elem = NULL;
+	return layout;
+}
+
+static void add(struct ntdb_layout *layout, union ntdb_layout_elem elem)
+{
+	layout->elem = realloc(layout->elem,
+			       sizeof(layout->elem[0])
+			       * (layout->num_elems+1));
+	layout->elem[layout->num_elems++] = elem;
+}
+
+void ntdb_layout_add_freetable(struct ntdb_layout *layout)
+{
+	union ntdb_layout_elem elem;
+	elem.base.type = FREETABLE;
+	add(layout, elem);
+}
+
+void ntdb_layout_add_free(struct ntdb_layout *layout, ntdb_len_t len,
+			 unsigned ftable)
+{
+	union ntdb_layout_elem elem;
+	elem.base.type = FREE;
+	elem.free.len = len;
+	elem.free.ftable_num = ftable;
+	add(layout, elem);
+}
+
+void ntdb_layout_add_capability(struct ntdb_layout *layout,
+			       uint64_t type,
+			       bool write_breaks,
+			       bool check_breaks,
+			       bool open_breaks,
+			       ntdb_len_t extra)
+{
+	union ntdb_layout_elem elem;
+	elem.base.type = CAPABILITY;
+	elem.capability.type = type;
+	if (write_breaks)
+		elem.capability.type |= NTDB_CAP_NOWRITE;
+	if (open_breaks)
+		elem.capability.type |= NTDB_CAP_NOOPEN;
+	if (check_breaks)
+		elem.capability.type |= NTDB_CAP_NOCHECK;
+	elem.capability.extra = extra;
+	add(layout, elem);
+}
+
+static NTDB_DATA dup_key(NTDB_DATA key)
+{
+	NTDB_DATA ret;
+	ret.dsize = key.dsize;
+	ret.dptr = malloc(ret.dsize);
+	memcpy(ret.dptr, key.dptr, ret.dsize);
+	return ret;
+}
+
+void ntdb_layout_add_used(struct ntdb_layout *layout,
+			 NTDB_DATA key, NTDB_DATA data,
+			 ntdb_len_t extra)
+{
+	union ntdb_layout_elem elem;
+	elem.base.type = DATA;
+	elem.used.key = dup_key(key);
+	elem.used.data = dup_key(data);
+	elem.used.extra = extra;
+	add(layout, elem);
+}
+
+static ntdb_len_t free_record_len(ntdb_len_t len)
+{
+	return sizeof(struct ntdb_used_record) + len;
+}
+
+static ntdb_len_t data_record_len(struct tle_used *used)
+{
+	ntdb_len_t len;
+	len = sizeof(struct ntdb_used_record)
+		+ used->key.dsize + used->data.dsize + used->extra;
+	assert(len >= sizeof(struct ntdb_free_record));
+	return len;
+}
+
+static ntdb_len_t hashtable_len(struct tle_hashtable *htable)
+{
+	return sizeof(struct ntdb_used_record)
+		+ (sizeof(ntdb_off_t) << NTDB_SUBLEVEL_HASH_BITS)
+		+ htable->extra;
+}
+
+static ntdb_len_t capability_len(struct tle_capability *cap)
+{
+	return sizeof(struct ntdb_capability) + cap->extra;
+}
+
+static ntdb_len_t freetable_len(struct tle_freetable *ftable)
+{
+	return sizeof(struct ntdb_freetable);
+}
+
+static void set_free_record(void *mem, ntdb_len_t len)
+{
+	/* We do all the work in add_to_freetable */
+}
+
+static void add_zero_pad(struct ntdb_used_record *u, size_t len, size_t extra)
+{
+	if (extra)
+		((char *)(u + 1))[len] = '\0';
+}
+
+static void set_data_record(void *mem, struct ntdb_context *ntdb,
+			    struct tle_used *used)
+{
+	struct ntdb_used_record *u = mem;
+
+	set_header(ntdb, u, NTDB_USED_MAGIC, used->key.dsize, used->data.dsize,
+		   used->key.dsize + used->data.dsize + used->extra,
+		   ntdb_hash(ntdb, used->key.dptr, used->key.dsize));
+	memcpy(u + 1, used->key.dptr, used->key.dsize);
+	memcpy((char *)(u + 1) + used->key.dsize,
+	       used->data.dptr, used->data.dsize);
+	add_zero_pad(u, used->key.dsize + used->data.dsize, used->extra);
+}
+
+static void set_hashtable(void *mem, struct ntdb_context *ntdb,
+			  struct tle_hashtable *htable)
+{
+	struct ntdb_used_record *u = mem;
+	ntdb_len_t len = sizeof(ntdb_off_t) << NTDB_SUBLEVEL_HASH_BITS;
+
+	set_header(ntdb, u, NTDB_HTABLE_MAGIC, 0, len, len + htable->extra, 0);
+	memset(u + 1, 0, len);
+	add_zero_pad(u, len, htable->extra);
+}
+
+static void set_capability(void *mem, struct ntdb_context *ntdb,
+			   struct tle_capability *cap, struct ntdb_header *hdr,
+			   ntdb_off_t last_cap)
+{
+	struct ntdb_capability *c = mem;
+	ntdb_len_t len = sizeof(*c) - sizeof(struct ntdb_used_record) + cap->extra;
+
+	c->type = cap->type;
+	c->next = 0;
+	set_header(ntdb, &c->hdr, NTDB_CAP_MAGIC, 0, len, len, 0);
+
+	/* Append to capability list. */
+	if (!last_cap) {
+		hdr->capabilities = cap->base.off;
+	} else {
+		c = (struct ntdb_capability *)((char *)hdr + last_cap);
+		c->next = cap->base.off;
+	}
+}
+
+static void set_freetable(void *mem, struct ntdb_context *ntdb,
+			 struct tle_freetable *freetable, struct ntdb_header *hdr,
+			 ntdb_off_t last_ftable)
+{
+	struct ntdb_freetable *ftable = mem;
+	memset(ftable, 0, sizeof(*ftable));
+	set_header(ntdb, &ftable->hdr, NTDB_FTABLE_MAGIC, 0,
+			sizeof(*ftable) - sizeof(ftable->hdr),
+			sizeof(*ftable) - sizeof(ftable->hdr), 0);
+
+	if (last_ftable) {
+		ftable = (struct ntdb_freetable *)((char *)hdr + last_ftable);
+		ftable->next = freetable->base.off;
+	} else {
+		hdr->free_table = freetable->base.off;
+	}
+}
+
+static void add_to_freetable(struct ntdb_context *ntdb,
+			     ntdb_off_t eoff,
+			     ntdb_off_t elen,
+			     unsigned ftable,
+			     struct tle_freetable *freetable)
+{
+	ntdb->ftable_off = freetable->base.off;
+	ntdb->ftable = ftable;
+	add_free_record(ntdb, eoff, sizeof(struct ntdb_used_record) + elen,
+			NTDB_LOCK_WAIT, false);
+}
+
+static ntdb_off_t hbucket_off(ntdb_off_t group_start, unsigned ingroup)
+{
+	return group_start
+		+ (ingroup % (1 << NTDB_HASH_GROUP_BITS)) * sizeof(ntdb_off_t);
+}
+
+/* Get bits from a value. */
+static uint32_t bits(uint64_t val, unsigned start, unsigned num)
+{
+	assert(num <= 32);
+	return (val >> start) & ((1U << num) - 1);
+}
+
+/* We take bits from the top: that way we can lock whole sections of the hash
+ * by using lock ranges. */
+static uint32_t use_bits(uint64_t h, unsigned num, unsigned *used)
+{
+	*used += num;
+	return bits(h, 64 - *used, num);
+}
+
+static ntdb_off_t encode_offset(ntdb_off_t new_off, unsigned bucket,
+			       uint64_t h)
+{
+	return bucket
+		| new_off
+		| ((uint64_t)bits(h, 64 - NTDB_OFF_UPPER_STEAL_EXTRA,
+				  NTDB_OFF_UPPER_STEAL_EXTRA)
+		   << NTDB_OFF_HASH_EXTRA_BIT);
+}
+
+/* FIXME: Our hash table handling here is primitive: we don't expand! */
+static void add_to_hashtable(struct ntdb_context *ntdb,
+			     ntdb_off_t eoff,
+			     NTDB_DATA key)
+{
+	uint64_t h = ntdb_hash(ntdb, key.dptr, key.dsize);
+	ntdb_off_t b_off, group_start;
+	unsigned i, group, in_group;
+	unsigned used = 0;
+
+	group = use_bits(h, NTDB_TOPLEVEL_HASH_BITS-NTDB_HASH_GROUP_BITS, &used);
+	in_group = use_bits(h, NTDB_HASH_GROUP_BITS, &used);
+
+	group_start = offsetof(struct ntdb_header, hashtable)
+		+ group * (sizeof(ntdb_off_t) << NTDB_HASH_GROUP_BITS);
+
+	for (i = 0; i < (1 << NTDB_HASH_GROUP_BITS); i++) {
+		unsigned bucket = (in_group + i) % (1 << NTDB_HASH_GROUP_BITS);
+
+		b_off = hbucket_off(group_start, bucket);
+		if (ntdb_read_off(ntdb, b_off) == 0) {
+			ntdb_write_off(ntdb, b_off,
+				      encode_offset(eoff, in_group, h));
+			return;
+		}
+	}
+	abort();
+}
+
+static struct tle_freetable *find_ftable(struct ntdb_layout *layout, unsigned num)
+{
+	unsigned i;
+
+	for (i = 0; i < layout->num_elems; i++) {
+		if (layout->elem[i].base.type != FREETABLE)
+			continue;
+		if (num == 0)
+			return &layout->elem[i].ftable;
+		num--;
+	}
+	abort();
+}
+
+/* FIXME: Support NTDB_CONVERT */
+struct ntdb_context *ntdb_layout_get(struct ntdb_layout *layout,
+				   void (*freefn)(void *),
+				   union ntdb_attribute *attr)
+{
+	unsigned int i;
+	ntdb_off_t off, len, last_ftable, last_cap;
+	char *mem;
+	struct ntdb_context *ntdb;
+
+	off = sizeof(struct ntdb_header);
+
+	/* First pass of layout: calc lengths */
+	for (i = 0; i < layout->num_elems; i++) {
+		union ntdb_layout_elem *e = &layout->elem[i];
+		e->base.off = off;
+		switch (e->base.type) {
+		case FREETABLE:
+			len = freetable_len(&e->ftable);
+			break;
+		case FREE:
+			len = free_record_len(e->free.len);
+			break;
+		case DATA:
+			len = data_record_len(&e->used);
+			break;
+		case HASHTABLE:
+			len = hashtable_len(&e->hashtable);
+			break;
+		case CAPABILITY:
+			len = capability_len(&e->capability);
+			break;
+		default:
+			abort();
+		}
+		off += len;
+	}
+
+	mem = malloc(off);
+	/* Fill with some weird pattern. */
+	memset(mem, 0x99, off);
+	/* Now populate our header, cribbing from a real NTDB header. */
+	ntdb = ntdb_open(NULL, NTDB_INTERNAL, O_RDWR, 0, attr);
+	memcpy(mem, ntdb->file->map_ptr, sizeof(struct ntdb_header));
+
+	/* Mug the ntdb we have to make it use this. */
+	freefn(ntdb->file->map_ptr);
+	ntdb->file->map_ptr = mem;
+	ntdb->file->map_size = off;
+
+	last_ftable = 0;
+	last_cap = 0;
+	for (i = 0; i < layout->num_elems; i++) {
+		union ntdb_layout_elem *e = &layout->elem[i];
+		switch (e->base.type) {
+		case FREETABLE:
+			set_freetable(mem + e->base.off, ntdb, &e->ftable,
+				     (struct ntdb_header *)mem, last_ftable);
+			last_ftable = e->base.off;
+			break;
+		case FREE:
+			set_free_record(mem + e->base.off, e->free.len);
+			break;
+		case DATA:
+			set_data_record(mem + e->base.off, ntdb, &e->used);
+			break;
+		case HASHTABLE:
+			set_hashtable(mem + e->base.off, ntdb, &e->hashtable);
+			break;
+		case CAPABILITY:
+			set_capability(mem + e->base.off, ntdb, &e->capability,
+				       (struct ntdb_header *)mem, last_cap);
+			last_cap = e->base.off;
+			break;
+		}
+	}
+	/* Must have a free table! */
+	assert(last_ftable);
+
+	/* Now fill the free and hash tables. */
+	for (i = 0; i < layout->num_elems; i++) {
+		union ntdb_layout_elem *e = &layout->elem[i];
+		switch (e->base.type) {
+		case FREE:
+			add_to_freetable(ntdb, e->base.off, e->free.len,
+					 e->free.ftable_num,
+					 find_ftable(layout, e->free.ftable_num));
+			break;
+		case DATA:
+			add_to_hashtable(ntdb, e->base.off, e->used.key);
+			break;
+		default:
+			break;
+		}
+	}
+
+	ntdb->ftable_off = find_ftable(layout, 0)->base.off;
+	return ntdb;
+}
+
+void ntdb_layout_write(struct ntdb_layout *layout, void (*freefn)(void *),
+		       union ntdb_attribute *attr, const char *filename)
+{
+	struct ntdb_context *ntdb = ntdb_layout_get(layout, freefn, attr);
+	int fd;
+
+	fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT,  0600);
+	if (fd < 0)
+		err(1, "opening %s for writing", filename);
+	if (write(fd, ntdb->file->map_ptr, ntdb->file->map_size)
+	    != ntdb->file->map_size)
+		err(1, "writing %s", filename);
+	close(fd);
+	ntdb_close(ntdb);
+}
+
+void ntdb_layout_free(struct ntdb_layout *layout)
+{
+	unsigned int i;
+
+	for (i = 0; i < layout->num_elems; i++) {
+		if (layout->elem[i].base.type == DATA) {
+			free(layout->elem[i].used.key.dptr);
+			free(layout->elem[i].used.data.dptr);
+		}
+	}
+	free(layout->elem);
+	free(layout);
+}
diff --git a/lib/ntdb/test/layout.h b/lib/ntdb/test/layout.h
new file mode 100644
index 0000000000..bcd20b8965
--- /dev/null
+++ b/lib/ntdb/test/layout.h
@@ -0,0 +1,87 @@
+#ifndef NTDB_TEST_LAYOUT_H
+#define NTDB_TEST_LAYOUT_H
+#include "private.h"
+
+struct ntdb_layout *new_ntdb_layout(void);
+void ntdb_layout_add_freetable(struct ntdb_layout *layout);
+void ntdb_layout_add_free(struct ntdb_layout *layout, ntdb_len_t len,
+			 unsigned ftable);
+void ntdb_layout_add_used(struct ntdb_layout *layout,
+			 NTDB_DATA key, NTDB_DATA data,
+			 ntdb_len_t extra);
+void ntdb_layout_add_capability(struct ntdb_layout *layout,
+			       uint64_t type,
+			       bool write_breaks,
+			       bool check_breaks,
+			       bool open_breaks,
+			       ntdb_len_t extra);
+
+#if 0 /* FIXME: Allow allocation of subtables */
+void ntdb_layout_add_hashtable(struct ntdb_layout *layout,
+			      int htable_parent, /* -1 == toplevel */
+			      unsigned int bucket,
+			      ntdb_len_t extra);
+#endif
+/* freefn is needed if we're using failtest_free. */
+struct ntdb_context *ntdb_layout_get(struct ntdb_layout *layout,
+				   void (*freefn)(void *),
+				   union ntdb_attribute *attr);
+void ntdb_layout_write(struct ntdb_layout *layout, void (*freefn)(void *),
+		       union ntdb_attribute *attr, const char *filename);
+
+void ntdb_layout_free(struct ntdb_layout *layout);
+
+enum layout_type {
+	FREETABLE, FREE, DATA, HASHTABLE, CAPABILITY
+};
+
+/* Shared by all union members. */
+struct tle_base {
+	enum layout_type type;
+	ntdb_off_t off;
+};
+
+struct tle_freetable {
+	struct tle_base base;
+};
+
+struct tle_free {
+	struct tle_base base;
+	ntdb_len_t len;
+	unsigned ftable_num;
+};
+
+struct tle_used {
+	struct tle_base base;
+	NTDB_DATA key;
+	NTDB_DATA data;
+	ntdb_len_t extra;
+};
+
+struct tle_hashtable {
+	struct tle_base base;
+	int parent;
+	unsigned int bucket;
+	ntdb_len_t extra;
+};
+
+struct tle_capability {
+	struct tle_base base;
+	uint64_t type;
+	ntdb_len_t extra;
+};
+
+union ntdb_layout_elem {
+	struct tle_base base;
+	struct tle_freetable ftable;
+	struct tle_free free;
+	struct tle_used used;
+	struct tle_hashtable hashtable;
+	struct tle_capability capability;
+};
+
+struct ntdb_layout {
+	unsigned int num_elems;
+	union ntdb_layout_elem *elem;
+};
+#endif /* NTDB_TEST_LAYOUT_H */
diff --git a/lib/ntdb/test/lock-tracking.c b/lib/ntdb/test/lock-tracking.c
new file mode 100644
index 0000000000..525a5c4ca7
--- /dev/null
+++ b/lib/ntdb/test/lock-tracking.c
@@ -0,0 +1,147 @@
+/* We save the locks so we can reaquire them. */
+#include "private.h" /* For NTDB_HASH_LOCK_START, etc. */
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include "tap-interface.h"
+#include "lock-tracking.h"
+
+struct lock {
+	struct lock *next;
+	unsigned int off;
+	unsigned int len;
+	int type;
+};
+static struct lock *locks;
+int locking_errors = 0;
+bool suppress_lockcheck = false;
+bool nonblocking_locks;
+int locking_would_block = 0;
+void (*unlock_callback)(int fd);
+
+int fcntl_with_lockcheck(int fd, int cmd, ... /* arg */ )
+{
+	va_list ap;
+	int ret, arg3;
+	struct flock *fl;
+	bool may_block = false;
+
+	if (cmd != F_SETLK && cmd != F_SETLKW) {
+		/* This may be totally bogus, but we don't know in general. */
+		va_start(ap, cmd);
+		arg3 = va_arg(ap, int);
+		va_end(ap);
+
+		return fcntl(fd, cmd, arg3);
+	}
+
+	va_start(ap, cmd);
+	fl = va_arg(ap, struct flock *);
+	va_end(ap);
+
+	if (cmd == F_SETLKW && nonblocking_locks) {
+		cmd = F_SETLK;
+		may_block = true;
+	}
+	ret = fcntl(fd, cmd, fl);
+
+	/* Detect when we failed, but might have been OK if we waited. */
+	if (may_block && ret == -1 && (errno == EAGAIN || errno == EACCES)) {
+		locking_would_block++;
+	}
+
+	if (fl->l_type == F_UNLCK) {
+		struct lock **l;
+		struct lock *old = NULL;
+
+		for (l = &locks; *l; l = &(*l)->next) {
+			if ((*l)->off == fl->l_start
+			    && (*l)->len == fl->l_len) {
+				if (ret == 0) {
+					old = *l;
+					*l = (*l)->next;
+					free(old);
+				}
+				break;
+			}
+		}
+		if (!old && !suppress_lockcheck) {
+			diag("Unknown unlock %u@%u - %i",
+			     (int)fl->l_len, (int)fl->l_start, ret);
+			locking_errors++;
+		}
+	} else {
+		struct lock *new, *i;
+		unsigned int fl_end = fl->l_start + fl->l_len;
+		if (fl->l_len == 0)
+			fl_end = (unsigned int)-1;
+
+		/* Check for overlaps: we shouldn't do this. */
+		for (i = locks; i; i = i->next) {
+			unsigned int i_end = i->off + i->len;
+			if (i->len == 0)
+				i_end = (unsigned int)-1;
+
+			if (fl->l_start >= i->off && fl->l_start < i_end)
+				break;
+			if (fl_end > i->off && fl_end < i_end)
+				break;
+
+			/* ntdb_allrecord_lock does this, handle adjacent: */
+			if (fl->l_start > NTDB_HASH_LOCK_START
+			    && fl->l_start == i_end && fl->l_type == i->type) {
+				if (ret == 0) {
+					i->len = fl->l_len
+						? i->len + fl->l_len
+						: 0;
+				}
+				goto done;
+			}
+		}
+		if (i) {
+			/* Special case: upgrade of allrecord lock. */
+			if (i->type == F_RDLCK && fl->l_type == F_WRLCK
+			    && i->off == NTDB_HASH_LOCK_START
+			    && fl->l_start == NTDB_HASH_LOCK_START
+			    && i->len == 0
+			    && fl->l_len == 0) {
+				if (ret == 0)
+					i->type = F_WRLCK;
+				goto done;
+			}
+			if (!suppress_lockcheck) {
+				diag("%s lock %u@%u overlaps %u@%u",
+				     fl->l_type == F_WRLCK ? "write" : "read",
+				     (int)fl->l_len, (int)fl->l_start,
+				     i->len, (int)i->off);
+				locking_errors++;
+			}
+		}
+
+		if (ret == 0) {
+			new = malloc(sizeof *new);
+			new->off = fl->l_start;
+			new->len = fl->l_len;
+			new->type = fl->l_type;
+			new->next = locks;
+			locks = new;
+		}
+	}
+done:
+	if (ret == 0 && fl->l_type == F_UNLCK && unlock_callback)
+		unlock_callback(fd);
+	return ret;
+}
+
+unsigned int forget_locking(void)
+{
+	unsigned int num = 0;
+	while (locks) {
+		struct lock *next = locks->next;
+		free(locks);
+		locks = next;
+		num++;
+	}
+	return num;
+}
diff --git a/lib/ntdb/test/lock-tracking.h b/lib/ntdb/test/lock-tracking.h
new file mode 100644
index 0000000000..f2c9c44653
--- /dev/null
+++ b/lib/ntdb/test/lock-tracking.h
@@ -0,0 +1,25 @@
+#ifndef LOCK_TRACKING_H
+#define LOCK_TRACKING_H
+#include <stdbool.h>
+
+/* Set this if you want a callback after fnctl unlock. */
+extern void (*unlock_callback)(int fd);
+
+/* Replacement fcntl. */
+int fcntl_with_lockcheck(int fd, int cmd, ... /* arg */ );
+
+/* Discard locking info: returns number of locks outstanding. */
+unsigned int forget_locking(void);
+
+/* Number of errors in locking. */
+extern int locking_errors;
+
+/* Suppress lock checking. */
+extern bool suppress_lockcheck;
+
+/* Make all locks non-blocking. */
+extern bool nonblocking_locks;
+
+/* Number of times we failed a lock because we made it non-blocking. */
+extern int locking_would_block;
+#endif /* LOCK_TRACKING_H */
diff --git a/lib/ntdb/test/logging.c b/lib/ntdb/test/logging.c
new file mode 100644
index 0000000000..2819dd7cad
--- /dev/null
+++ b/lib/ntdb/test/logging.c
@@ -0,0 +1,30 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include "tap-interface.h"
+#include "logging.h"
+
+unsigned tap_log_messages;
+const char *log_prefix = "";
+char *log_last = NULL;
+bool suppress_logging;
+
+union ntdb_attribute tap_log_attr = {
+	.log = { .base = { .attr = NTDB_ATTRIBUTE_LOG },
+		 .fn = tap_log_fn }
+};
+
+void tap_log_fn(struct ntdb_context *ntdb,
+		enum ntdb_log_level level,
+		enum NTDB_ERROR ecode,
+		const char *message, void *priv)
+{
+	if (suppress_logging)
+		return;
+
+	diag("ntdb log level %u: %s: %s%s",
+	     level, ntdb_errorstr(ecode), log_prefix, message);
+	if (log_last)
+		free(log_last);
+	log_last = strdup(message);
+	tap_log_messages++;
+}
diff --git a/lib/ntdb/test/logging.h b/lib/ntdb/test/logging.h
new file mode 100644
index 0000000000..0336ccaba3
--- /dev/null
+++ b/lib/ntdb/test/logging.h
@@ -0,0 +1,17 @@
+#ifndef NTDB_TEST_LOGGING_H
+#define NTDB_TEST_LOGGING_H
+#include "ntdb.h"
+#include <stdbool.h>
+#include <string.h>
+
+extern bool suppress_logging;
+extern const char *log_prefix;
+extern unsigned tap_log_messages;
+extern union ntdb_attribute tap_log_attr;
+extern char *log_last;
+
+void tap_log_fn(struct ntdb_context *ntdb,
+		enum ntdb_log_level level,
+		enum NTDB_ERROR ecode,
+		const char *message, void *priv);
+#endif /* NTDB_TEST_LOGGING_H */
diff --git a/lib/ntdb/test/ntdb-source.h b/lib/ntdb/test/ntdb-source.h
new file mode 100644
index 0000000000..52268440d2
--- /dev/null
+++ b/lib/ntdb/test/ntdb-source.h
@@ -0,0 +1,11 @@
+#include "config.h"
+#include "check.c"
+#include "free.c"
+#include "hash.c"
+#include "io.c"
+#include "lock.c"
+#include "open.c"
+#include "summary.c"
+#include "ntdb.c"
+#include "transaction.c"
+#include "traverse.c"
diff --git a/lib/ntdb/test/run-001-encode.c b/lib/ntdb/test/run-001-encode.c
new file mode 100644
index 0000000000..12965676a2
--- /dev/null
+++ b/lib/ntdb/test/run-001-encode.c
@@ -0,0 +1,41 @@
+#include "ntdb-source.h"
+#include "tap-interface.h"
+#include "logging.h"
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_used_record rec;
+	struct ntdb_context ntdb = { .log_fn = tap_log_fn };
+
+	plan_tests(64 + 32 + 48*6 + 1);
+
+	/* We should be able to encode any data value. */
+	for (i = 0; i < 64; i++)
+		ok1(set_header(&ntdb, &rec, NTDB_USED_MAGIC, 0, 1ULL << i,
+			       1ULL << i, 0) == 0);
+
+	/* And any key and data with < 64 bits between them. */
+	for (i = 0; i < 32; i++) {
+		ntdb_len_t dlen = 1ULL >> (63 - i), klen = 1ULL << i;
+		ok1(set_header(&ntdb, &rec, NTDB_USED_MAGIC, klen, dlen,
+			       klen + dlen, 0)  == 0);
+	}
+
+	/* We should neatly encode all values. */
+	for (i = 0; i < 48; i++) {
+		uint64_t h = 1ULL << (i < 5 ? i : 4);
+		uint64_t klen = 1ULL << (i < 16 ? i : 15);
+		uint64_t dlen = 1ULL << i;
+		uint64_t xlen = 1ULL << (i < 32 ? i : 31);
+		ok1(set_header(&ntdb, &rec, NTDB_USED_MAGIC, klen, dlen,
+			       klen+dlen+xlen, h) == 0);
+		ok1(rec_key_length(&rec) == klen);
+		ok1(rec_data_length(&rec) == dlen);
+		ok1(rec_extra_padding(&rec) == xlen);
+		ok1((uint64_t)rec_hash(&rec) == h);
+		ok1(rec_magic(&rec) == NTDB_USED_MAGIC);
+	}
+	ok1(tap_log_messages == 0);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/run-001-fls.c b/lib/ntdb/test/run-001-fls.c
new file mode 100644
index 0000000000..ec61294c6f
--- /dev/null
+++ b/lib/ntdb/test/run-001-fls.c
@@ -0,0 +1,33 @@
+#include "ntdb-source.h"
+#include "tap-interface.h"
+
+static unsigned int dumb_fls(uint64_t num)
+{
+	int i;
+
+	for (i = 63; i >= 0; i--) {
+		if (num & (1ULL << i))
+			break;
+	}
+	return i + 1;
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i, j;
+
+	plan_tests(64 * 64 + 2);
+
+	ok1(fls64(0) == 0);
+	ok1(dumb_fls(0) == 0);
+
+	for (i = 0; i < 64; i++) {
+		for (j = 0; j < 64; j++) {
+			uint64_t val = (1ULL << i) | (1ULL << j);
+			ok(fls64(val) == dumb_fls(val),
+			   "%llu -> %u should be %u", (long long)val,
+			   fls64(val), dumb_fls(val));
+		}
+	}
+	return exit_status();
+}
diff --git a/lib/ntdb/test/run-01-new_database.c b/lib/ntdb/test/run-01-new_database.c
new file mode 100644
index 0000000000..ae70e86e07
--- /dev/null
+++ b/lib/ntdb/test/run-01-new_database.c
@@ -0,0 +1,34 @@
+#include <ccan/failtest/failtest_override.h>
+#include "ntdb-source.h"
+#include "tap-interface.h"
+#include <ccan/failtest/failtest.h>
+#include "logging.h"
+#include "failtest_helper.h"
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_INTERNAL, NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_INTERNAL|NTDB_CONVERT, NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT };
+
+	failtest_init(argc, argv);
+	failtest_hook = block_repeat_failures;
+	failtest_exit_check = exit_check_log;
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 3);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb = ntdb_open("run-new_database.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		if (!ok1(ntdb))
+			failtest_exit(exit_status());
+
+		failtest_suppress = true;
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+		failtest_suppress = false;
+		ntdb_close(ntdb);
+		if (!ok1(tap_log_messages == 0))
+			break;
+	}
+	failtest_exit(exit_status());
+}
diff --git a/lib/ntdb/test/run-02-expand.c b/lib/ntdb/test/run-02-expand.c
new file mode 100644
index 0000000000..abf1569388
--- /dev/null
+++ b/lib/ntdb/test/run-02-expand.c
@@ -0,0 +1,62 @@
+#include <ccan/failtest/failtest_override.h>
+#include "ntdb-source.h"
+#include "tap-interface.h"
+#include <ccan/failtest/failtest.h>
+#include "logging.h"
+#include "failtest_helper.h"
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	uint64_t val;
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_INTERNAL, NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_INTERNAL|NTDB_CONVERT, NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT };
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 11 + 1);
+
+	failtest_init(argc, argv);
+	failtest_hook = block_repeat_failures;
+	failtest_exit_check = exit_check_log;
+
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		failtest_suppress = true;
+		ntdb = ntdb_open("run-expand.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		if (!ok1(ntdb))
+			break;
+
+		val = ntdb->file->map_size;
+		/* Need some hash lock for expand. */
+		ok1(ntdb_lock_hashes(ntdb, 0, 1, F_WRLCK, NTDB_LOCK_WAIT) == 0);
+		failtest_suppress = false;
+		if (!ok1(ntdb_expand(ntdb, 1) == 0)) {
+			failtest_suppress = true;
+			ntdb_close(ntdb);
+			break;
+		}
+		failtest_suppress = true;
+
+		ok1(ntdb->file->map_size >= val + 1 * NTDB_EXTENSION_FACTOR);
+		ok1(ntdb_unlock_hashes(ntdb, 0, 1, F_WRLCK) == 0);
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+		val = ntdb->file->map_size;
+		ok1(ntdb_lock_hashes(ntdb, 0, 1, F_WRLCK, NTDB_LOCK_WAIT) == 0);
+		failtest_suppress = false;
+		if (!ok1(ntdb_expand(ntdb, 1024) == 0)) {
+			failtest_suppress = true;
+			ntdb_close(ntdb);
+			break;
+		}
+		failtest_suppress = true;
+		ok1(ntdb_unlock_hashes(ntdb, 0, 1, F_WRLCK) == 0);
+		ok1(ntdb->file->map_size >= val + 1024 * NTDB_EXTENSION_FACTOR);
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+		ntdb_close(ntdb);
+	}
+
+	ok1(tap_log_messages == 0);
+	failtest_exit(exit_status());
+}
diff --git a/lib/ntdb/test/run-03-coalesce.c b/lib/ntdb/test/run-03-coalesce.c
new file mode 100644
index 0000000000..f93b33a1c3
--- /dev/null
+++ b/lib/ntdb/test/run-03-coalesce.c
@@ -0,0 +1,178 @@
+#include "ntdb-source.h"
+#include "tap-interface.h"
+#include "logging.h"
+#include "layout.h"
+
+static ntdb_len_t free_record_length(struct ntdb_context *ntdb, ntdb_off_t off)
+{
+	struct ntdb_free_record f;
+	enum NTDB_ERROR ecode;
+
+	ecode = ntdb_read_convert(ntdb, off, &f, sizeof(f));
+	if (ecode != NTDB_SUCCESS)
+		return ecode;
+	if (frec_magic(&f) != NTDB_FREE_MAGIC)
+		return NTDB_ERR_CORRUPT;
+	return frec_len(&f);
+}
+
+int main(int argc, char *argv[])
+{
+	ntdb_off_t b_off, test;
+	struct ntdb_context *ntdb;
+	struct ntdb_layout *layout;
+	NTDB_DATA data, key;
+	ntdb_len_t len;
+
+	/* FIXME: Test NTDB_CONVERT */
+	/* FIXME: Test lock order fail. */
+
+	plan_tests(42);
+	data = ntdb_mkdata("world", 5);
+	key = ntdb_mkdata("hello", 5);
+
+	/* No coalescing can be done due to EOF */
+	layout = new_ntdb_layout();
+	ntdb_layout_add_freetable(layout);
+	len = 1024;
+	ntdb_layout_add_free(layout, len, 0);
+	ntdb_layout_write(layout, free, &tap_log_attr, "run-03-coalesce.ntdb");
+	/* NOMMAP is for lockcheck. */
+	ntdb = ntdb_open("run-03-coalesce.ntdb", NTDB_NOMMAP, O_RDWR, 0,
+		       &tap_log_attr);
+	ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+	ok1(free_record_length(ntdb, layout->elem[1].base.off) == len);
+
+	/* Figure out which bucket free entry is. */
+	b_off = bucket_off(ntdb->ftable_off, size_to_bucket(len));
+	/* Lock and fail to coalesce. */
+	ok1(ntdb_lock_free_bucket(ntdb, b_off, NTDB_LOCK_WAIT) == 0);
+	test = layout->elem[1].base.off;
+	ok1(coalesce(ntdb, layout->elem[1].base.off, b_off, len, &test)
+	    == 0);
+	ntdb_unlock_free_bucket(ntdb, b_off);
+	ok1(free_record_length(ntdb, layout->elem[1].base.off) == len);
+	ok1(test == layout->elem[1].base.off);
+	ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+	ntdb_close(ntdb);
+	ntdb_layout_free(layout);
+
+	/* No coalescing can be done due to used record */
+	layout = new_ntdb_layout();
+	ntdb_layout_add_freetable(layout);
+	ntdb_layout_add_free(layout, 1024, 0);
+	ntdb_layout_add_used(layout, key, data, 6);
+	ntdb_layout_write(layout, free, &tap_log_attr, "run-03-coalesce.ntdb");
+	/* NOMMAP is for lockcheck. */
+	ntdb = ntdb_open("run-03-coalesce.ntdb", NTDB_NOMMAP, O_RDWR, 0,
+		       &tap_log_attr);
+	ok1(free_record_length(ntdb, layout->elem[1].base.off) == 1024);
+	ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+	/* Figure out which bucket free entry is. */
+	b_off = bucket_off(ntdb->ftable_off, size_to_bucket(1024));
+	/* Lock and fail to coalesce. */
+	ok1(ntdb_lock_free_bucket(ntdb, b_off, NTDB_LOCK_WAIT) == 0);
+	test = layout->elem[1].base.off;
+	ok1(coalesce(ntdb, layout->elem[1].base.off, b_off, 1024, &test)
+	    == 0);
+	ntdb_unlock_free_bucket(ntdb, b_off);
+	ok1(free_record_length(ntdb, layout->elem[1].base.off) == 1024);
+	ok1(test == layout->elem[1].base.off);
+	ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+	ntdb_close(ntdb);
+	ntdb_layout_free(layout);
+
+	/* Coalescing can be done due to two free records, then EOF */
+	layout = new_ntdb_layout();
+	ntdb_layout_add_freetable(layout);
+	ntdb_layout_add_free(layout, 1024, 0);
+	ntdb_layout_add_free(layout, 2048, 0);
+	ntdb_layout_write(layout, free, &tap_log_attr, "run-03-coalesce.ntdb");
+	/* NOMMAP is for lockcheck. */
+	ntdb = ntdb_open("run-03-coalesce.ntdb", NTDB_NOMMAP, O_RDWR, 0,
+		       &tap_log_attr);
+	ok1(free_record_length(ntdb, layout->elem[1].base.off) == 1024);
+	ok1(free_record_length(ntdb, layout->elem[2].base.off) == 2048);
+	ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+	/* Figure out which bucket (first) free entry is. */
+	b_off = bucket_off(ntdb->ftable_off, size_to_bucket(1024));
+	/* Lock and coalesce. */
+	ok1(ntdb_lock_free_bucket(ntdb, b_off, NTDB_LOCK_WAIT) == 0);
+	test = layout->elem[2].base.off;
+	ok1(coalesce(ntdb, layout->elem[1].base.off, b_off, 1024, &test)
+	    == 1024 + sizeof(struct ntdb_used_record) + 2048);
+	/* Should tell us it's erased this one... */
+	ok1(test == NTDB_ERR_NOEXIST);
+	ok1(ntdb->file->allrecord_lock.count == 0 && ntdb->file->num_lockrecs == 0);
+	ok1(free_record_length(ntdb, layout->elem[1].base.off)
+	    == 1024 + sizeof(struct ntdb_used_record) + 2048);
+	ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+	ntdb_close(ntdb);
+	ntdb_layout_free(layout);
+
+	/* Coalescing can be done due to two free records, then data */
+	layout = new_ntdb_layout();
+	ntdb_layout_add_freetable(layout);
+	ntdb_layout_add_free(layout, 1024, 0);
+	ntdb_layout_add_free(layout, 512, 0);
+	ntdb_layout_add_used(layout, key, data, 6);
+	ntdb_layout_write(layout, free, &tap_log_attr, "run-03-coalesce.ntdb");
+	/* NOMMAP is for lockcheck. */
+	ntdb = ntdb_open("run-03-coalesce.ntdb", NTDB_NOMMAP, O_RDWR, 0,
+		       &tap_log_attr);
+	ok1(free_record_length(ntdb, layout->elem[1].base.off) == 1024);
+	ok1(free_record_length(ntdb, layout->elem[2].base.off) == 512);
+	ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+	/* Figure out which bucket free entry is. */
+	b_off = bucket_off(ntdb->ftable_off, size_to_bucket(1024));
+	/* Lock and coalesce. */
+	ok1(ntdb_lock_free_bucket(ntdb, b_off, NTDB_LOCK_WAIT) == 0);
+	test = layout->elem[2].base.off;
+	ok1(coalesce(ntdb, layout->elem[1].base.off, b_off, 1024, &test)
+	    == 1024 + sizeof(struct ntdb_used_record) + 512);
+	ok1(ntdb->file->allrecord_lock.count == 0 && ntdb->file->num_lockrecs == 0);
+	ok1(free_record_length(ntdb, layout->elem[1].base.off)
+	    == 1024 + sizeof(struct ntdb_used_record) + 512);
+	ok1(test == NTDB_ERR_NOEXIST);
+	ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+	ntdb_close(ntdb);
+	ntdb_layout_free(layout);
+
+	/* Coalescing can be done due to three free records, then EOF */
+	layout = new_ntdb_layout();
+	ntdb_layout_add_freetable(layout);
+	ntdb_layout_add_free(layout, 1024, 0);
+	ntdb_layout_add_free(layout, 512, 0);
+	ntdb_layout_add_free(layout, 256, 0);
+	ntdb_layout_write(layout, free, &tap_log_attr, "run-03-coalesce.ntdb");
+	/* NOMMAP is for lockcheck. */
+	ntdb = ntdb_open("run-03-coalesce.ntdb", NTDB_NOMMAP, O_RDWR, 0,
+		       &tap_log_attr);
+	ok1(free_record_length(ntdb, layout->elem[1].base.off) == 1024);
+	ok1(free_record_length(ntdb, layout->elem[2].base.off) == 512);
+	ok1(free_record_length(ntdb, layout->elem[3].base.off) == 256);
+	ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+	/* Figure out which bucket free entry is. */
+	b_off = bucket_off(ntdb->ftable_off, size_to_bucket(1024));
+	/* Lock and coalesce. */
+	ok1(ntdb_lock_free_bucket(ntdb, b_off, NTDB_LOCK_WAIT) == 0);
+	test = layout->elem[2].base.off;
+	ok1(coalesce(ntdb, layout->elem[1].base.off, b_off, 1024, &test)
+	    == 1024 + sizeof(struct ntdb_used_record) + 512
+	    + sizeof(struct ntdb_used_record) + 256);
+	ok1(ntdb->file->allrecord_lock.count == 0
+	    && ntdb->file->num_lockrecs == 0);
+	ok1(free_record_length(ntdb, layout->elem[1].base.off)
+	    == 1024 + sizeof(struct ntdb_used_record) + 512
+	    + sizeof(struct ntdb_used_record) + 256);
+	ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+	ntdb_close(ntdb);
+	ntdb_layout_free(layout);
+
+	ok1(tap_log_messages == 0);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/run-04-basichash.c b/lib/ntdb/test/run-04-basichash.c
new file mode 100644
index 0000000000..6e3bdc012d
--- /dev/null
+++ b/lib/ntdb/test/run-04-basichash.c
@@ -0,0 +1,260 @@
+#include "ntdb-source.h"
+#include "tap-interface.h"
+#include "logging.h"
+
+/* We rig the hash so adjacent-numbered records always clash. */
+static uint64_t clash(const void *key, size_t len, uint64_t seed, void *priv)
+{
+	return ((uint64_t)*(const unsigned int *)key)
+		<< (64 - NTDB_TOPLEVEL_HASH_BITS - 1);
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i, j;
+	struct ntdb_context *ntdb;
+	unsigned int v;
+	struct ntdb_used_record rec;
+	NTDB_DATA key = { (unsigned char *)&v, sizeof(v) };
+	NTDB_DATA dbuf = { (unsigned char *)&v, sizeof(v) };
+	union ntdb_attribute hattr = { .hash = { .base = { NTDB_ATTRIBUTE_HASH },
+						.fn = clash } };
+	int flags[] = { NTDB_INTERNAL, NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_INTERNAL|NTDB_CONVERT, NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT,
+	};
+
+	hattr.base.next = &tap_log_attr;
+
+	plan_tests(sizeof(flags) / sizeof(flags[0])
+		   * (91 + (2 * ((1 << NTDB_HASH_GROUP_BITS) - 1))) + 1);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		struct hash_info h;
+		ntdb_off_t new_off, off, subhash;
+
+		ntdb = ntdb_open("run-04-basichash.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &hattr);
+		ok1(ntdb);
+		if (!ntdb)
+			continue;
+
+		v = 0;
+		/* Should not find it. */
+		ok1(find_and_lock(ntdb, key, F_WRLCK, &h, &rec, NULL) == 0);
+		/* Should have created correct hash. */
+		ok1(h.h == ntdb_hash(ntdb, key.dptr, key.dsize));
+		/* Should have located space in group 0, bucket 0. */
+		ok1(h.group_start == offsetof(struct ntdb_header, hashtable));
+		ok1(h.home_bucket == 0);
+		ok1(h.found_bucket == 0);
+		ok1(h.hash_used == NTDB_TOPLEVEL_HASH_BITS);
+
+		/* Should have lock on bucket 0 */
+		ok1(h.hlock_start == 0);
+		ok1(h.hlock_range ==
+		    1ULL << (64-(NTDB_TOPLEVEL_HASH_BITS-NTDB_HASH_GROUP_BITS)));
+		ok1((ntdb->flags & NTDB_NOLOCK) || ntdb->file->num_lockrecs == 1);
+		ok1((ntdb->flags & NTDB_NOLOCK)
+		    || ntdb->file->lockrecs[0].off == NTDB_HASH_LOCK_START);
+		/* FIXME: Check lock length */
+
+		/* Allocate a new record. */
+		new_off = alloc(ntdb, key.dsize, dbuf.dsize, h.h,
+				NTDB_USED_MAGIC, false);
+		ok1(!NTDB_OFF_IS_ERR(new_off));
+
+		/* We should be able to add it now. */
+		ok1(add_to_hash(ntdb, &h, new_off) == 0);
+
+		/* Make sure we fill it in for later finding. */
+		off = new_off + sizeof(struct ntdb_used_record);
+		ok1(!ntdb->io->twrite(ntdb, off, key.dptr, key.dsize));
+		off += key.dsize;
+		ok1(!ntdb->io->twrite(ntdb, off, dbuf.dptr, dbuf.dsize));
+
+		/* We should be able to unlock that OK. */
+		ok1(ntdb_unlock_hashes(ntdb, h.hlock_start, h.hlock_range,
+				      F_WRLCK) == 0);
+
+		/* Database should be consistent. */
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+		/* Now, this should give a successful lookup. */
+		ok1(find_and_lock(ntdb, key, F_WRLCK, &h, &rec, NULL)
+		    == new_off);
+		/* Should have created correct hash. */
+		ok1(h.h == ntdb_hash(ntdb, key.dptr, key.dsize));
+		/* Should have located space in group 0, bucket 0. */
+		ok1(h.group_start == offsetof(struct ntdb_header, hashtable));
+		ok1(h.home_bucket == 0);
+		ok1(h.found_bucket == 0);
+		ok1(h.hash_used == NTDB_TOPLEVEL_HASH_BITS);
+
+		/* Should have lock on bucket 0 */
+		ok1(h.hlock_start == 0);
+		ok1(h.hlock_range ==
+		    1ULL << (64-(NTDB_TOPLEVEL_HASH_BITS-NTDB_HASH_GROUP_BITS)));
+		ok1((ntdb->flags & NTDB_NOLOCK) || ntdb->file->num_lockrecs == 1);
+		ok1((ntdb->flags & NTDB_NOLOCK)
+		    || ntdb->file->lockrecs[0].off == NTDB_HASH_LOCK_START);
+		/* FIXME: Check lock length */
+
+		ok1(ntdb_unlock_hashes(ntdb, h.hlock_start, h.hlock_range,
+				      F_WRLCK) == 0);
+
+		/* Database should be consistent. */
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+		/* Test expansion. */
+		v = 1;
+		ok1(find_and_lock(ntdb, key, F_WRLCK, &h, &rec, NULL) == 0);
+		/* Should have created correct hash. */
+		ok1(h.h == ntdb_hash(ntdb, key.dptr, key.dsize));
+		/* Should have located space in group 0, bucket 1. */
+		ok1(h.group_start == offsetof(struct ntdb_header, hashtable));
+		ok1(h.home_bucket == 0);
+		ok1(h.found_bucket == 1);
+		ok1(h.hash_used == NTDB_TOPLEVEL_HASH_BITS);
+
+		/* Should have lock on bucket 0 */
+		ok1(h.hlock_start == 0);
+		ok1(h.hlock_range ==
+		    1ULL << (64-(NTDB_TOPLEVEL_HASH_BITS-NTDB_HASH_GROUP_BITS)));
+		ok1((ntdb->flags & NTDB_NOLOCK) || ntdb->file->num_lockrecs == 1);
+		ok1((ntdb->flags & NTDB_NOLOCK)
+		    || ntdb->file->lockrecs[0].off == NTDB_HASH_LOCK_START);
+		/* FIXME: Check lock length */
+
+		/* Make it expand 0'th bucket. */
+		ok1(expand_group(ntdb, &h) == 0);
+		/* First one should be subhash, next should be empty. */
+		ok1(is_subhash(h.group[0]));
+		subhash = (h.group[0] & NTDB_OFF_MASK);
+		for (j = 1; j < (1 << NTDB_HASH_GROUP_BITS); j++)
+			ok1(h.group[j] == 0);
+
+		ok1(ntdb_write_convert(ntdb, h.group_start,
+				      h.group, sizeof(h.group)) == 0);
+		ok1(ntdb_unlock_hashes(ntdb, h.hlock_start, h.hlock_range,
+				      F_WRLCK) == 0);
+
+		/* Should be happy with expansion. */
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+		/* Should be able to find it. */
+		v = 0;
+		ok1(find_and_lock(ntdb, key, F_WRLCK, &h, &rec, NULL)
+		    == new_off);
+		/* Should have created correct hash. */
+		ok1(h.h == ntdb_hash(ntdb, key.dptr, key.dsize));
+		/* Should have located space in expanded group 0, bucket 0. */
+		ok1(h.group_start == subhash + sizeof(struct ntdb_used_record));
+		ok1(h.home_bucket == 0);
+		ok1(h.found_bucket == 0);
+		ok1(h.hash_used == NTDB_TOPLEVEL_HASH_BITS
+		    + NTDB_SUBLEVEL_HASH_BITS);
+
+		/* Should have lock on bucket 0 */
+		ok1(h.hlock_start == 0);
+		ok1(h.hlock_range ==
+		    1ULL << (64-(NTDB_TOPLEVEL_HASH_BITS-NTDB_HASH_GROUP_BITS)));
+		ok1((ntdb->flags & NTDB_NOLOCK) || ntdb->file->num_lockrecs == 1);
+		ok1((ntdb->flags & NTDB_NOLOCK)
+		    || ntdb->file->lockrecs[0].off == NTDB_HASH_LOCK_START);
+		/* FIXME: Check lock length */
+
+		/* Simple delete should work. */
+		ok1(delete_from_hash(ntdb, &h) == 0);
+		ok1(add_free_record(ntdb, new_off,
+				    sizeof(struct ntdb_used_record)
+				    + rec_key_length(&rec)
+				    + rec_data_length(&rec)
+				    + rec_extra_padding(&rec),
+				    NTDB_LOCK_NOWAIT, false) == 0);
+		ok1(ntdb_unlock_hashes(ntdb, h.hlock_start, h.hlock_range,
+				      F_WRLCK) == 0);
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+		/* Test second-level expansion: should expand 0th bucket. */
+		v = 0;
+		ok1(find_and_lock(ntdb, key, F_WRLCK, &h, &rec, NULL) == 0);
+		/* Should have created correct hash. */
+		ok1(h.h == ntdb_hash(ntdb, key.dptr, key.dsize));
+		/* Should have located space in group 0, bucket 0. */
+		ok1(h.group_start == subhash + sizeof(struct ntdb_used_record));
+		ok1(h.home_bucket == 0);
+		ok1(h.found_bucket == 0);
+		ok1(h.hash_used == NTDB_TOPLEVEL_HASH_BITS+NTDB_SUBLEVEL_HASH_BITS);
+
+		/* Should have lock on bucket 0 */
+		ok1(h.hlock_start == 0);
+		ok1(h.hlock_range ==
+		    1ULL << (64-(NTDB_TOPLEVEL_HASH_BITS-NTDB_HASH_GROUP_BITS)));
+		ok1((ntdb->flags & NTDB_NOLOCK) || ntdb->file->num_lockrecs == 1);
+		ok1((ntdb->flags & NTDB_NOLOCK)
+		    || ntdb->file->lockrecs[0].off == NTDB_HASH_LOCK_START);
+		/* FIXME: Check lock length */
+
+		ok1(expand_group(ntdb, &h) == 0);
+		/* First one should be subhash, next should be empty. */
+		ok1(is_subhash(h.group[0]));
+		subhash = (h.group[0] & NTDB_OFF_MASK);
+		for (j = 1; j < (1 << NTDB_HASH_GROUP_BITS); j++)
+			ok1(h.group[j] == 0);
+		ok1(ntdb_write_convert(ntdb, h.group_start,
+				      h.group, sizeof(h.group)) == 0);
+		ok1(ntdb_unlock_hashes(ntdb, h.hlock_start, h.hlock_range,
+				      F_WRLCK) == 0);
+
+		/* Should be happy with expansion. */
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+		ok1(find_and_lock(ntdb, key, F_WRLCK, &h, &rec, NULL) == 0);
+		/* Should have created correct hash. */
+		ok1(h.h == ntdb_hash(ntdb, key.dptr, key.dsize));
+		/* Should have located space in group 0, bucket 0. */
+		ok1(h.group_start == subhash + sizeof(struct ntdb_used_record));
+		ok1(h.home_bucket == 0);
+		ok1(h.found_bucket == 0);
+		ok1(h.hash_used == NTDB_TOPLEVEL_HASH_BITS
+		    + NTDB_SUBLEVEL_HASH_BITS * 2);
+
+		/* We should be able to add it now. */
+		/* Allocate a new record. */
+		new_off = alloc(ntdb, key.dsize, dbuf.dsize, h.h,
+				NTDB_USED_MAGIC, false);
+		ok1(!NTDB_OFF_IS_ERR(new_off));
+		ok1(add_to_hash(ntdb, &h, new_off) == 0);
+
+		/* Make sure we fill it in for later finding. */
+		off = new_off + sizeof(struct ntdb_used_record);
+		ok1(!ntdb->io->twrite(ntdb, off, key.dptr, key.dsize));
+		off += key.dsize;
+		ok1(!ntdb->io->twrite(ntdb, off, dbuf.dptr, dbuf.dsize));
+
+		/* We should be able to unlock that OK. */
+		ok1(ntdb_unlock_hashes(ntdb, h.hlock_start, h.hlock_range,
+				      F_WRLCK) == 0);
+
+		/* Database should be consistent. */
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+		/* Should be able to find it. */
+		v = 0;
+		ok1(find_and_lock(ntdb, key, F_WRLCK, &h, &rec, NULL)
+		    == new_off);
+		/* Should have created correct hash. */
+		ok1(h.h == ntdb_hash(ntdb, key.dptr, key.dsize));
+		/* Should have located space in expanded group 0, bucket 0. */
+		ok1(h.group_start == subhash + sizeof(struct ntdb_used_record));
+		ok1(h.home_bucket == 0);
+		ok1(h.found_bucket == 0);
+		ok1(h.hash_used == NTDB_TOPLEVEL_HASH_BITS
+		    + NTDB_SUBLEVEL_HASH_BITS * 2);
+
+		ntdb_close(ntdb);
+	}
+
+	ok1(tap_log_messages == 0);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/run-05-readonly-open.c b/lib/ntdb/test/run-05-readonly-open.c
new file mode 100644
index 0000000000..dd5aa26d0d
--- /dev/null
+++ b/lib/ntdb/test/run-05-readonly-open.c
@@ -0,0 +1,71 @@
+#include <ccan/failtest/failtest_override.h>
+#include "ntdb-source.h"
+#include "tap-interface.h"
+#include <ccan/failtest/failtest.h>
+#include "logging.h"
+#include "failtest_helper.h"
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_CONVERT, NTDB_NOMMAP|NTDB_CONVERT };
+	NTDB_DATA key = ntdb_mkdata("key", 3);
+	NTDB_DATA data = ntdb_mkdata("data", 4), d;
+	union ntdb_attribute seed_attr;
+	unsigned int msgs = 0;
+
+	failtest_init(argc, argv);
+	failtest_hook = block_repeat_failures;
+	failtest_exit_check = exit_check_log;
+
+	seed_attr.base.attr = NTDB_ATTRIBUTE_SEED;
+	seed_attr.base.next = &tap_log_attr;
+	seed_attr.seed.seed = 0;
+
+	failtest_suppress = true;
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 11);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb = ntdb_open("run-05-readonly-open.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600,
+			       &seed_attr);
+		ok1(ntdb_store(ntdb, key, data, NTDB_INSERT) == 0);
+		ntdb_close(ntdb);
+
+		failtest_suppress = false;
+		ntdb = ntdb_open("run-05-readonly-open.ntdb", flags[i],
+			       O_RDONLY, 0600, &tap_log_attr);
+		if (!ok1(ntdb))
+			break;
+		ok1(tap_log_messages == msgs);
+		/* Fetch should succeed, stores should fail. */
+		if (!ok1(ntdb_fetch(ntdb, key, &d) == 0))
+			goto fail;
+		ok1(ntdb_deq(d, data));
+		free(d.dptr);
+		if (!ok1(ntdb_store(ntdb, key, data, NTDB_MODIFY)
+			 == NTDB_ERR_RDONLY))
+			goto fail;
+		ok1(tap_log_messages == ++msgs);
+		if (!ok1(ntdb_store(ntdb, key, data, NTDB_INSERT)
+			 == NTDB_ERR_RDONLY))
+			goto fail;
+		ok1(tap_log_messages == ++msgs);
+		failtest_suppress = true;
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+		ntdb_close(ntdb);
+		ok1(tap_log_messages == msgs);
+		/* SIGH: failtest bug, it doesn't save the ntdb file because
+		 * we have it read-only.  If we go around again, it gets
+		 * changed underneath us and things get screwy. */
+		if (failtest_has_failed())
+			break;
+	}
+	failtest_exit(exit_status());
+
+fail:
+	failtest_suppress = true;
+	ntdb_close(ntdb);
+	failtest_exit(exit_status());
+}
diff --git a/lib/ntdb/test/run-10-simple-store.c b/lib/ntdb/test/run-10-simple-store.c
new file mode 100644
index 0000000000..6e718bf61f
--- /dev/null
+++ b/lib/ntdb/test/run-10-simple-store.c
@@ -0,0 +1,58 @@
+#include <ccan/failtest/failtest_override.h>
+#include "ntdb-source.h"
+#include "tap-interface.h"
+#include <ccan/failtest/failtest.h>
+#include "logging.h"
+#include "failtest_helper.h"
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_INTERNAL, NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_INTERNAL|NTDB_CONVERT, NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT };
+	NTDB_DATA key = ntdb_mkdata("key", 3);
+	NTDB_DATA data = ntdb_mkdata("data", 4);
+
+	failtest_init(argc, argv);
+	failtest_hook = block_repeat_failures;
+	failtest_exit_check = exit_check_log;
+
+	failtest_suppress = true;
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 7 + 1);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb = ntdb_open("run-10-simple-store.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		if (!ok1(ntdb))
+			break;
+		/* Modify should fail. */
+		failtest_suppress = false;
+		if (!ok1(ntdb_store(ntdb, key, data, NTDB_MODIFY)
+			 == NTDB_ERR_NOEXIST))
+			goto fail;
+		failtest_suppress = true;
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+		/* Insert should succeed. */
+		failtest_suppress = false;
+		if (!ok1(ntdb_store(ntdb, key, data, NTDB_INSERT) == 0))
+			goto fail;
+		failtest_suppress = true;
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+		/* Second insert should fail. */
+		failtest_suppress = false;
+		if (!ok1(ntdb_store(ntdb, key, data, NTDB_INSERT)
+			 == NTDB_ERR_EXISTS))
+			goto fail;
+		failtest_suppress = true;
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+		ntdb_close(ntdb);
+	}
+	ok1(tap_log_messages == 0);
+	failtest_exit(exit_status());
+
+fail:
+	failtest_suppress = true;
+	ntdb_close(ntdb);
+	failtest_exit(exit_status());
+}
diff --git a/lib/ntdb/test/run-11-simple-fetch.c b/lib/ntdb/test/run-11-simple-fetch.c
new file mode 100644
index 0000000000..525cf46444
--- /dev/null
+++ b/lib/ntdb/test/run-11-simple-fetch.c
@@ -0,0 +1,58 @@
+#include <ccan/failtest/failtest_override.h>
+#include "ntdb-source.h"
+#include "tap-interface.h"
+#include <ccan/failtest/failtest.h>
+#include "logging.h"
+#include "failtest_helper.h"
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_INTERNAL, NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_INTERNAL|NTDB_CONVERT, NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT };
+	NTDB_DATA key = ntdb_mkdata("key", 3);
+	NTDB_DATA data = ntdb_mkdata("data", 4);
+
+	failtest_init(argc, argv);
+	failtest_hook = block_repeat_failures;
+	failtest_exit_check = exit_check_log;
+
+	failtest_suppress = true;
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 8 + 1);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb = ntdb_open("run-11-simple-fetch.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		ok1(ntdb);
+		if (ntdb) {
+			NTDB_DATA d = { NULL, 0 }; /* Bogus GCC warning */
+
+			/* fetch should fail. */
+			failtest_suppress = false;
+			if (!ok1(ntdb_fetch(ntdb, key, &d) == NTDB_ERR_NOEXIST))
+				goto fail;
+			failtest_suppress = true;
+			ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+			/* Insert should succeed. */
+			ok1(ntdb_store(ntdb, key, data, NTDB_INSERT) == 0);
+			ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+			/* Fetch should now work. */
+			failtest_suppress = false;
+			if (!ok1(ntdb_fetch(ntdb, key, &d) == NTDB_SUCCESS))
+				goto fail;
+			failtest_suppress = true;
+			ok1(ntdb_deq(d, data));
+			free(d.dptr);
+			ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+			ntdb_close(ntdb);
+		}
+	}
+	ok1(tap_log_messages == 0);
+	failtest_exit(exit_status());
+
+fail:
+	failtest_suppress = true;
+	ntdb_close(ntdb);
+	failtest_exit(exit_status());
+}
diff --git a/lib/ntdb/test/run-12-check.c b/lib/ntdb/test/run-12-check.c
new file mode 100644
index 0000000000..6040637048
--- /dev/null
+++ b/lib/ntdb/test/run-12-check.c
@@ -0,0 +1,46 @@
+#include "private.h"
+#include <ccan/failtest/failtest_override.h>
+#include "ntdb-source.h"
+#include "tap-interface.h"
+#include <ccan/failtest/failtest.h>
+#include "logging.h"
+#include "failtest_helper.h"
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_INTERNAL,
+			NTDB_INTERNAL|NTDB_CONVERT,
+			NTDB_CONVERT };
+	NTDB_DATA key = ntdb_mkdata("key", 3);
+	NTDB_DATA data = ntdb_mkdata("data", 4);
+
+	failtest_init(argc, argv);
+	failtest_hook = block_repeat_failures;
+	failtest_exit_check = exit_check_log;
+
+	failtest_suppress = true;
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 3 + 1);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb = ntdb_open("run-12-check.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		ok1(ntdb);
+		ok1(ntdb_store(ntdb, key, data, NTDB_INSERT) == 0);
+
+		/* This is what we really want to test: ntdb_check(). */
+		failtest_suppress = false;
+		if (!ok1(ntdb_check(ntdb, NULL, NULL) == 0))
+			goto fail;
+		failtest_suppress = true;
+
+		ntdb_close(ntdb);
+	}
+	ok1(tap_log_messages == 0);
+	failtest_exit(exit_status());
+
+fail:
+	failtest_suppress = true;
+	ntdb_close(ntdb);
+	failtest_exit(exit_status());
+}
diff --git a/lib/ntdb/test/run-15-append.c b/lib/ntdb/test/run-15-append.c
new file mode 100644
index 0000000000..3c208137f2
--- /dev/null
+++ b/lib/ntdb/test/run-15-append.c
@@ -0,0 +1,130 @@
+#include "ntdb-source.h"
+#include "tap-interface.h"
+#include <ccan/ilog/ilog.h>
+#include "logging.h"
+
+#define MAX_SIZE 13100
+#define SIZE_STEP 131
+
+static ntdb_off_t ntdb_offset(struct ntdb_context *ntdb, NTDB_DATA key)
+{
+	ntdb_off_t off;
+	struct ntdb_used_record urec;
+	struct hash_info h;
+
+	off = find_and_lock(ntdb, key, F_RDLCK, &h, &urec, NULL);
+	if (NTDB_OFF_IS_ERR(off))
+		return 0;
+	ntdb_unlock_hashes(ntdb, h.hlock_start, h.hlock_range, F_RDLCK);
+	return off;
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i, j, moves;
+	struct ntdb_context *ntdb;
+	unsigned char *buffer;
+	ntdb_off_t oldoff = 0, newoff;
+	int flags[] = { NTDB_INTERNAL, NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_INTERNAL|NTDB_CONVERT, NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT };
+	NTDB_DATA key = ntdb_mkdata("key", 3);
+	NTDB_DATA data;
+
+	buffer = malloc(MAX_SIZE);
+	for (i = 0; i < MAX_SIZE; i++)
+		buffer[i] = i;
+
+	plan_tests(sizeof(flags) / sizeof(flags[0])
+		   * ((3 + MAX_SIZE/SIZE_STEP * 5) * 2 + 7)
+		   + 1);
+
+	/* Using ntdb_store. */
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb = ntdb_open("run-append.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		ok1(ntdb);
+		if (!ntdb)
+			continue;
+
+		moves = 0;
+		for (j = 0; j < MAX_SIZE; j += SIZE_STEP) {
+			data.dptr = buffer;
+			data.dsize = j;
+			ok1(ntdb_store(ntdb, key, data, NTDB_REPLACE) == 0);
+			ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+			ok1(ntdb_fetch(ntdb, key, &data) == NTDB_SUCCESS);
+			ok1(data.dsize == j);
+			ok1(memcmp(data.dptr, buffer, data.dsize) == 0);
+			free(data.dptr);
+			newoff = ntdb_offset(ntdb, key);
+			if (newoff != oldoff)
+				moves++;
+			oldoff = newoff;
+		}
+		ok1(!ntdb->file || (ntdb->file->allrecord_lock.count == 0
+				   && ntdb->file->num_lockrecs == 0));
+		/* We should increase by 50% each time... */
+		ok(moves <= ilog64(j / SIZE_STEP)*2,
+		   "Moved %u times", moves);
+		ntdb_close(ntdb);
+	}
+
+	/* Using ntdb_append. */
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		size_t prev_len = 0;
+		ntdb = ntdb_open("run-append.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		ok1(ntdb);
+		if (!ntdb)
+			continue;
+
+		moves = 0;
+		for (j = 0; j < MAX_SIZE; j += SIZE_STEP) {
+			data.dptr = buffer + prev_len;
+			data.dsize = j - prev_len;
+			ok1(ntdb_append(ntdb, key, data) == 0);
+			ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+			ok1(ntdb_fetch(ntdb, key, &data) == NTDB_SUCCESS);
+			ok1(data.dsize == j);
+			ok1(memcmp(data.dptr, buffer, data.dsize) == 0);
+			free(data.dptr);
+			prev_len = data.dsize;
+			newoff = ntdb_offset(ntdb, key);
+			if (newoff != oldoff)
+				moves++;
+			oldoff = newoff;
+		}
+		ok1(!ntdb->file || (ntdb->file->allrecord_lock.count == 0
+				   && ntdb->file->num_lockrecs == 0));
+		/* We should increase by 50% each time... */
+		ok(moves <= ilog64(j / SIZE_STEP)*2,
+		   "Moved %u times", moves);
+		ntdb_close(ntdb);
+	}
+
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb = ntdb_open("run-append.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		ok1(ntdb);
+		if (!ntdb)
+			continue;
+
+		/* Huge initial store. */
+		data.dptr = buffer;
+		data.dsize = MAX_SIZE;
+		ok1(ntdb_append(ntdb, key, data) == 0);
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+		ok1(ntdb_fetch(ntdb, key, &data) == NTDB_SUCCESS);
+		ok1(data.dsize == MAX_SIZE);
+		ok1(memcmp(data.dptr, buffer, data.dsize) == 0);
+		free(data.dptr);
+		ok1(!ntdb->file || (ntdb->file->allrecord_lock.count == 0
+				   && ntdb->file->num_lockrecs == 0));
+		ntdb_close(ntdb);
+	}
+
+	ok1(tap_log_messages == 0);
+	free(buffer);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/run-20-growhash.c b/lib/ntdb/test/run-20-growhash.c
new file mode 100644
index 0000000000..5559370f2a
--- /dev/null
+++ b/lib/ntdb/test/run-20-growhash.c
@@ -0,0 +1,137 @@
+#include "ntdb-source.h"
+#include "tap-interface.h"
+#include "logging.h"
+
+static uint64_t myhash(const void *key, size_t len, uint64_t seed, void *priv)
+{
+	return *(const uint64_t *)key;
+}
+
+static void add_bits(uint64_t *val, unsigned new, unsigned new_bits,
+		     unsigned *done)
+{
+	*done += new_bits;
+	*val |= ((uint64_t)new << (64 - *done));
+}
+
+static uint64_t make_key(unsigned topgroup, unsigned topbucket,
+			 unsigned subgroup1, unsigned subbucket1,
+			 unsigned subgroup2, unsigned subbucket2)
+{
+	uint64_t key = 0;
+	unsigned done = 0;
+
+	add_bits(&key, topgroup, NTDB_TOPLEVEL_HASH_BITS - NTDB_HASH_GROUP_BITS,
+		 &done);
+	add_bits(&key, topbucket, NTDB_HASH_GROUP_BITS, &done);
+	add_bits(&key, subgroup1, NTDB_SUBLEVEL_HASH_BITS - NTDB_HASH_GROUP_BITS,
+		 &done);
+	add_bits(&key, subbucket1, NTDB_HASH_GROUP_BITS, &done);
+	add_bits(&key, subgroup2, NTDB_SUBLEVEL_HASH_BITS - NTDB_HASH_GROUP_BITS,
+		 &done);
+	add_bits(&key, subbucket2, NTDB_HASH_GROUP_BITS, &done);
+	return key;
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i, j;
+	struct ntdb_context *ntdb;
+	uint64_t kdata;
+	struct ntdb_used_record rec;
+	NTDB_DATA key = { (unsigned char *)&kdata, sizeof(kdata) };
+	NTDB_DATA dbuf = { (unsigned char *)&kdata, sizeof(kdata) };
+	union ntdb_attribute hattr = { .hash = { .base = { NTDB_ATTRIBUTE_HASH },
+						.fn = myhash } };
+	int flags[] = { NTDB_INTERNAL, NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_INTERNAL|NTDB_CONVERT, NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT,
+	};
+
+	hattr.base.next = &tap_log_attr;
+
+	plan_tests(sizeof(flags) / sizeof(flags[0])
+		   * (9 + (20 + 2 * ((1 << NTDB_HASH_GROUP_BITS) - 2))
+		      * (1 << NTDB_HASH_GROUP_BITS)) + 1);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		struct hash_info h;
+
+		ntdb = ntdb_open("run-20-growhash.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &hattr);
+		ok1(ntdb);
+		if (!ntdb)
+			continue;
+
+		/* Fill a group. */
+		for (j = 0; j < (1 << NTDB_HASH_GROUP_BITS); j++) {
+			kdata = make_key(0, j, 0, 0, 0, 0);
+			ok1(ntdb_store(ntdb, key, dbuf, NTDB_INSERT) == 0);
+		}
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+		/* Check first still exists. */
+		kdata = make_key(0, 0, 0, 0, 0, 0);
+		ok1(find_and_lock(ntdb, key, F_RDLCK, &h, &rec, NULL) != 0);
+		/* Should have created correct hash. */
+		ok1(h.h == ntdb_hash(ntdb, key.dptr, key.dsize));
+		/* Should have located space in group 0, bucket 0. */
+		ok1(h.group_start == offsetof(struct ntdb_header, hashtable));
+		ok1(h.home_bucket == 0);
+		ok1(h.found_bucket == 0);
+		ok1(h.hash_used == NTDB_TOPLEVEL_HASH_BITS);
+		/* Entire group should be full! */
+		for (j = 0; j < (1 << NTDB_HASH_GROUP_BITS); j++)
+			ok1(h.group[j] != 0);
+
+		ok1(ntdb_unlock_hashes(ntdb, h.hlock_start, h.hlock_range,
+				      F_RDLCK) == 0);
+
+		/* Now, add one more to each should expand (that) bucket. */
+		for (j = 0; j < (1 << NTDB_HASH_GROUP_BITS); j++) {
+			unsigned int k;
+			kdata = make_key(0, j, 0, 1, 0, 0);
+			ok1(ntdb_store(ntdb, key, dbuf, NTDB_INSERT) == 0);
+			ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+			ok1(find_and_lock(ntdb, key, F_RDLCK, &h, &rec, NULL));
+			/* Should have created correct hash. */
+			ok1(h.h == ntdb_hash(ntdb, key.dptr, key.dsize));
+			/* Should have moved to subhash */
+			ok1(h.group_start >= sizeof(struct ntdb_header));
+			ok1(h.home_bucket == 1);
+			ok1(h.found_bucket == 1);
+			ok1(h.hash_used == NTDB_TOPLEVEL_HASH_BITS
+			    + NTDB_SUBLEVEL_HASH_BITS);
+			ok1(ntdb_unlock_hashes(ntdb, h.hlock_start, h.hlock_range,
+					      F_RDLCK) == 0);
+
+			/* Keep adding, make it expand again. */
+			for (k = 2; k < (1 << NTDB_HASH_GROUP_BITS); k++) {
+				kdata = make_key(0, j, 0, k, 0, 0);
+				ok1(ntdb_store(ntdb, key, dbuf, NTDB_INSERT) == 0);
+				ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+			}
+
+			/* This should tip it over to sub-sub-hash. */
+			kdata = make_key(0, j, 0, 0, 0, 1);
+			ok1(ntdb_store(ntdb, key, dbuf, NTDB_INSERT) == 0);
+			ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+			ok1(find_and_lock(ntdb, key, F_RDLCK, &h, &rec, NULL));
+			/* Should have created correct hash. */
+			ok1(h.h == ntdb_hash(ntdb, key.dptr, key.dsize));
+			/* Should have moved to subhash */
+			ok1(h.group_start >= sizeof(struct ntdb_header));
+			ok1(h.home_bucket == 1);
+			ok1(h.found_bucket == 1);
+			ok1(h.hash_used == NTDB_TOPLEVEL_HASH_BITS
+			    + NTDB_SUBLEVEL_HASH_BITS + NTDB_SUBLEVEL_HASH_BITS);
+			ok1(ntdb_unlock_hashes(ntdb, h.hlock_start, h.hlock_range,
+					      F_RDLCK) == 0);
+		}
+		ntdb_close(ntdb);
+	}
+
+	ok1(tap_log_messages == 0);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/run-25-hashoverload.c b/lib/ntdb/test/run-25-hashoverload.c
new file mode 100644
index 0000000000..611eb71bf6
--- /dev/null
+++ b/lib/ntdb/test/run-25-hashoverload.c
@@ -0,0 +1,113 @@
+#include "ntdb-source.h"
+#include "tap-interface.h"
+#include "logging.h"
+
+static uint64_t badhash(const void *key, size_t len, uint64_t seed, void *priv)
+{
+	return 0;
+}
+
+static int trav(struct ntdb_context *ntdb, NTDB_DATA key, NTDB_DATA dbuf, void *p)
+{
+	if (p)
+		return ntdb_delete(ntdb, key);
+	return 0;
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i, j;
+	struct ntdb_context *ntdb;
+	NTDB_DATA key = { (unsigned char *)&j, sizeof(j) };
+	NTDB_DATA dbuf = { (unsigned char *)&j, sizeof(j) };
+	union ntdb_attribute hattr = { .hash = { .base = { NTDB_ATTRIBUTE_HASH },
+						.fn = badhash } };
+	int flags[] = { NTDB_INTERNAL, NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_INTERNAL|NTDB_CONVERT, NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT,
+	};
+
+	hattr.base.next = &tap_log_attr;
+
+	plan_tests(6883);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		NTDB_DATA d = { NULL, 0 }; /* Bogus GCC warning */
+
+		ntdb = ntdb_open("run-25-hashoverload.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &hattr);
+		ok1(ntdb);
+		if (!ntdb)
+			continue;
+
+		/* Fill a group. */
+		for (j = 0; j < (1 << NTDB_HASH_GROUP_BITS); j++) {
+			ok1(ntdb_store(ntdb, key, dbuf, NTDB_INSERT) == 0);
+		}
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+		/* Now store one last value: should form chain. */
+		ok1(ntdb_store(ntdb, key, dbuf, NTDB_INSERT) == 0);
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+		/* Check we can find them all. */
+		for (j = 0; j < (1 << NTDB_HASH_GROUP_BITS) + 1; j++) {
+			ok1(ntdb_fetch(ntdb, key, &d) == NTDB_SUCCESS);
+			ok1(d.dsize == sizeof(j));
+			ok1(d.dptr != NULL);
+			ok1(d.dptr && memcmp(d.dptr, &j, d.dsize) == 0);
+			free(d.dptr);
+		}
+
+		/* Now add a *lot* more. */
+		for (j = (1 << NTDB_HASH_GROUP_BITS) + 1;
+		     j < (16 << NTDB_HASH_GROUP_BITS);
+		     j++) {
+			ok1(ntdb_store(ntdb, key, dbuf, NTDB_INSERT) == 0);
+			ok1(ntdb_fetch(ntdb, key, &d) == NTDB_SUCCESS);
+			ok1(d.dsize == sizeof(j));
+			ok1(d.dptr != NULL);
+			ok1(d.dptr && memcmp(d.dptr, &j, d.dsize) == 0);
+			free(d.dptr);
+		}
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+		/* Traverse through them. */
+		ok1(ntdb_traverse(ntdb, trav, NULL) == j);
+
+		/* Empty the first chain-worth. */
+		for (j = 0; j < (1 << NTDB_HASH_GROUP_BITS); j++)
+			ok1(ntdb_delete(ntdb, key) == 0);
+
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+		for (j = (1 << NTDB_HASH_GROUP_BITS);
+		     j < (16 << NTDB_HASH_GROUP_BITS);
+		     j++) {
+			ok1(ntdb_fetch(ntdb, key, &d) == NTDB_SUCCESS);
+			ok1(d.dsize == sizeof(j));
+			ok1(d.dptr != NULL);
+			ok1(d.dptr && memcmp(d.dptr, &j, d.dsize) == 0);
+			free(d.dptr);
+		}
+
+		/* Traverse through them. */
+		ok1(ntdb_traverse(ntdb, trav, NULL)
+		    == (15 << NTDB_HASH_GROUP_BITS));
+
+		/* Re-add */
+		for (j = 0; j < (1 << NTDB_HASH_GROUP_BITS); j++) {
+			ok1(ntdb_store(ntdb, key, dbuf, NTDB_INSERT) == 0);
+		}
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+		/* Now try deleting as we go. */
+		ok1(ntdb_traverse(ntdb, trav, trav)
+		    == (16 << NTDB_HASH_GROUP_BITS));
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+		ok1(ntdb_traverse(ntdb, trav, NULL) == 0);
+		ntdb_close(ntdb);
+	}
+
+	ok1(tap_log_messages == 0);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/run-30-exhaust-before-expand.c b/lib/ntdb/test/run-30-exhaust-before-expand.c
new file mode 100644
index 0000000000..b94bc01bff
--- /dev/null
+++ b/lib/ntdb/test/run-30-exhaust-before-expand.c
@@ -0,0 +1,71 @@
+#include "ntdb-source.h"
+#include "tap-interface.h"
+#include "logging.h"
+
+static bool empty_freetable(struct ntdb_context *ntdb)
+{
+	struct ntdb_freetable ftab;
+	unsigned int i;
+
+	/* Now, free table should be completely exhausted in zone 0 */
+	if (ntdb_read_convert(ntdb, ntdb->ftable_off, &ftab, sizeof(ftab)) != 0)
+		abort();
+
+	for (i = 0; i < sizeof(ftab.buckets)/sizeof(ftab.buckets[0]); i++) {
+		if (ftab.buckets[i])
+			return false;
+	}
+	return true;
+}
+
+
+int main(int argc, char *argv[])
+{
+	unsigned int i, j;
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_INTERNAL, NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_INTERNAL|NTDB_CONVERT, NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT };
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 9 + 1);
+
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		NTDB_DATA k;
+		uint64_t size;
+		bool was_empty = false;
+
+		k.dptr = (void *)&j;
+		k.dsize = sizeof(j);
+
+		ntdb = ntdb_open("run-30-exhaust-before-expand.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		ok1(ntdb);
+		if (!ntdb)
+			continue;
+
+		ok1(empty_freetable(ntdb));
+		/* Need some hash lock for expand. */
+		ok1(ntdb_lock_hashes(ntdb, 0, 1, F_WRLCK, NTDB_LOCK_WAIT) == 0);
+		/* Create some free space. */
+		ok1(ntdb_expand(ntdb, 1) == 0);
+		ok1(ntdb_unlock_hashes(ntdb, 0, 1, F_WRLCK) == 0);
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+		ok1(!empty_freetable(ntdb));
+
+		size = ntdb->file->map_size;
+		/* Insert minimal-length records until we expand. */
+		for (j = 0; ntdb->file->map_size == size; j++) {
+			was_empty = empty_freetable(ntdb);
+			if (ntdb_store(ntdb, k, k, NTDB_INSERT) != 0)
+				err(1, "Failed to store record %i", j);
+		}
+
+		/* Would have been empty before expansion, but no longer. */
+		ok1(was_empty);
+		ok1(!empty_freetable(ntdb));
+		ntdb_close(ntdb);
+	}
+
+	ok1(tap_log_messages == 0);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/run-35-convert.c b/lib/ntdb/test/run-35-convert.c
new file mode 100644
index 0000000000..6a38d425cb
--- /dev/null
+++ b/lib/ntdb/test/run-35-convert.c
@@ -0,0 +1,54 @@
+#include "private.h"
+#include <ccan/failtest/failtest_override.h>
+#include "ntdb-source.h"
+#include "tap-interface.h"
+#include <ccan/failtest/failtest.h>
+#include "logging.h"
+#include "failtest_helper.h"
+
+int main(int argc, char *argv[])
+{
+	unsigned int i, messages = 0;
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_CONVERT, NTDB_NOMMAP|NTDB_CONVERT };
+
+	failtest_init(argc, argv);
+	failtest_hook = block_repeat_failures;
+	failtest_exit_check = exit_check_log;
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 4);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb = ntdb_open("run-35-convert.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		if (!ok1(ntdb))
+			failtest_exit(exit_status());
+
+		ntdb_close(ntdb);
+		/* If we say NTDB_CONVERT, it must be converted */
+		ntdb = ntdb_open("run-35-convert.ntdb",
+			       flags[i]|NTDB_CONVERT,
+			       O_RDWR, 0600, &tap_log_attr);
+		if (flags[i] & NTDB_CONVERT) {
+			if (!ntdb)
+				failtest_exit(exit_status());
+			ok1(ntdb_get_flags(ntdb) & NTDB_CONVERT);
+			ntdb_close(ntdb);
+		} else {
+			if (!ok1(!ntdb && errno == EIO))
+				failtest_exit(exit_status());
+			ok1(tap_log_messages == ++messages);
+			if (!ok1(log_last && strstr(log_last, "NTDB_CONVERT")))
+				failtest_exit(exit_status());
+		}
+
+		/* If don't say NTDB_CONVERT, it *may* be converted */
+		ntdb = ntdb_open("run-35-convert.ntdb",
+			       flags[i] & ~NTDB_CONVERT,
+			       O_RDWR, 0600, &tap_log_attr);
+		if (!ntdb)
+			failtest_exit(exit_status());
+		ok1(ntdb_get_flags(ntdb) == flags[i]);
+		ntdb_close(ntdb);
+	}
+	failtest_exit(exit_status());
+}
diff --git a/lib/ntdb/test/run-50-multiple-freelists.c b/lib/ntdb/test/run-50-multiple-freelists.c
new file mode 100644
index 0000000000..962462e5d4
--- /dev/null
+++ b/lib/ntdb/test/run-50-multiple-freelists.c
@@ -0,0 +1,70 @@
+#include "ntdb-source.h"
+#include "tap-interface.h"
+#include "logging.h"
+#include "layout.h"
+
+int main(int argc, char *argv[])
+{
+	ntdb_off_t off;
+	struct ntdb_context *ntdb;
+	struct ntdb_layout *layout;
+	NTDB_DATA key, data;
+	union ntdb_attribute seed;
+
+	/* This seed value previously tickled a layout.c bug. */
+	seed.base.attr = NTDB_ATTRIBUTE_SEED;
+	seed.seed.seed = 0xb1142bc054d035b4ULL;
+	seed.base.next = &tap_log_attr;
+
+	plan_tests(11);
+	key = ntdb_mkdata("Hello", 5);
+	data = ntdb_mkdata("world", 5);
+
+	/* Create a NTDB with three free tables. */
+	layout = new_ntdb_layout();
+	ntdb_layout_add_freetable(layout);
+	ntdb_layout_add_freetable(layout);
+	ntdb_layout_add_freetable(layout);
+	ntdb_layout_add_free(layout, 80, 0);
+	/* Used record prevent coalescing. */
+	ntdb_layout_add_used(layout, key, data, 6);
+	ntdb_layout_add_free(layout, 160, 1);
+	key.dsize--;
+	ntdb_layout_add_used(layout, key, data, 7);
+	ntdb_layout_add_free(layout, 320, 2);
+	key.dsize--;
+	ntdb_layout_add_used(layout, key, data, 8);
+	ntdb_layout_add_free(layout, 40, 0);
+	ntdb = ntdb_layout_get(layout, free, &seed);
+	ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+	off = get_free(ntdb, 0, 80 - sizeof(struct ntdb_used_record), 0,
+		       NTDB_USED_MAGIC, 0);
+	ok1(off == layout->elem[3].base.off);
+	ok1(ntdb->ftable_off == layout->elem[0].base.off);
+
+	off = get_free(ntdb, 0, 160 - sizeof(struct ntdb_used_record), 0,
+		       NTDB_USED_MAGIC, 0);
+	ok1(off == layout->elem[5].base.off);
+	ok1(ntdb->ftable_off == layout->elem[1].base.off);
+
+	off = get_free(ntdb, 0, 320 - sizeof(struct ntdb_used_record), 0,
+		       NTDB_USED_MAGIC, 0);
+	ok1(off == layout->elem[7].base.off);
+	ok1(ntdb->ftable_off == layout->elem[2].base.off);
+
+	off = get_free(ntdb, 0, 40 - sizeof(struct ntdb_used_record), 0,
+		       NTDB_USED_MAGIC, 0);
+	ok1(off == layout->elem[9].base.off);
+	ok1(ntdb->ftable_off == layout->elem[0].base.off);
+
+	/* Now we fail. */
+	off = get_free(ntdb, 0, 0, 1, NTDB_USED_MAGIC, 0);
+	ok1(off == 0);
+
+	ntdb_close(ntdb);
+	ntdb_layout_free(layout);
+
+	ok1(tap_log_messages == 0);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/run-56-open-during-transaction.c b/lib/ntdb/test/run-56-open-during-transaction.c
new file mode 100644
index 0000000000..f585aa13c8
--- /dev/null
+++ b/lib/ntdb/test/run-56-open-during-transaction.c
@@ -0,0 +1,165 @@
+#include "private.h"
+#include <unistd.h>
+#include "lock-tracking.h"
+
+static ssize_t pwrite_check(int fd, const void *buf, size_t count, off_t offset);
+static ssize_t write_check(int fd, const void *buf, size_t count);
+static int ftruncate_check(int fd, off_t length);
+
+#define pwrite pwrite_check
+#define write write_check
+#define fcntl fcntl_with_lockcheck
+#define ftruncate ftruncate_check
+
+#include "ntdb-source.h"
+#include "tap-interface.h"
+#include <stdlib.h>
+#include <stdbool.h>
+#include <stdarg.h>
+#include "external-agent.h"
+#include "logging.h"
+
+static struct agent *agent;
+static bool opened;
+static int errors = 0;
+#define TEST_DBNAME "run-56-open-during-transaction.ntdb"
+
+#undef write
+#undef pwrite
+#undef fcntl
+#undef ftruncate
+
+static bool is_same(const char *snapshot, const char *latest, off_t len)
+{
+	unsigned i;
+
+	for (i = 0; i < len; i++) {
+		if (snapshot[i] != latest[i])
+			return false;
+	}
+	return true;
+}
+
+static bool compare_file(int fd, const char *snapshot, off_t snapshot_len)
+{
+	char *contents;
+	bool ret;
+
+	/* over-length read serves as length check. */
+	contents = malloc(snapshot_len+1);
+	ret = pread(fd, contents, snapshot_len+1, 0) == snapshot_len
+		&& is_same(snapshot, contents, snapshot_len);
+	free(contents);
+	return ret;
+}
+
+static void check_file_intact(int fd)
+{
+	enum agent_return ret;
+	struct stat st;
+	char *contents;
+
+	fstat(fd, &st);
+	contents = malloc(st.st_size);
+	if (pread(fd, contents, st.st_size, 0) != st.st_size) {
+		diag("Read fail");
+		errors++;
+		return;
+	}
+
+	/* Ask agent to open file. */
+	ret = external_agent_operation(agent, OPEN, TEST_DBNAME);
+
+	/* It's OK to open it, but it must not have changed! */
+	if (!compare_file(fd, contents, st.st_size)) {
+		diag("Agent changed file after opening %s",
+		     agent_return_name(ret));
+		errors++;
+	}
+
+	if (ret == SUCCESS) {
+		ret = external_agent_operation(agent, CLOSE, NULL);
+		if (ret != SUCCESS) {
+			diag("Agent failed to close ntdb: %s",
+			     agent_return_name(ret));
+			errors++;
+		}
+	} else if (ret != WOULD_HAVE_BLOCKED) {
+		diag("Agent opening file gave %s",
+		     agent_return_name(ret));
+		errors++;
+	}
+
+	free(contents);
+}
+
+static void after_unlock(int fd)
+{
+	if (opened)
+		check_file_intact(fd);
+}
+
+static ssize_t pwrite_check(int fd,
+			    const void *buf, size_t count, off_t offset)
+{
+	if (opened)
+		check_file_intact(fd);
+
+	return pwrite(fd, buf, count, offset);
+}
+
+static ssize_t write_check(int fd, const void *buf, size_t count)
+{
+	if (opened)
+		check_file_intact(fd);
+
+	return write(fd, buf, count);
+}
+
+static int ftruncate_check(int fd, off_t length)
+{
+	if (opened)
+		check_file_intact(fd);
+
+	return ftruncate(fd, length);
+
+}
+
+int main(int argc, char *argv[])
+{
+	const int flags[] = { NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_CONVERT, NTDB_NOMMAP|NTDB_CONVERT };
+	int i;
+	struct ntdb_context *ntdb;
+	NTDB_DATA key, data;
+
+	plan_tests(sizeof(flags)/sizeof(flags[0]) * 5);
+	agent = prepare_external_agent();
+	if (!agent)
+		err(1, "preparing agent");
+
+	unlock_callback = after_unlock;
+	for (i = 0; i < sizeof(flags)/sizeof(flags[0]); i++) {
+		diag("Test with %s and %s\n",
+		     (flags[i] & NTDB_CONVERT) ? "CONVERT" : "DEFAULT",
+		     (flags[i] & NTDB_NOMMAP) ? "no mmap" : "mmap");
+		unlink(TEST_DBNAME);
+		ntdb = ntdb_open(TEST_DBNAME, flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		ok1(ntdb);
+
+		opened = true;
+		ok1(ntdb_transaction_start(ntdb) == 0);
+		key = ntdb_mkdata("hi", strlen("hi"));
+		data = ntdb_mkdata("world", strlen("world"));
+
+		ok1(ntdb_store(ntdb, key, data, NTDB_INSERT) == 0);
+		ok1(ntdb_transaction_commit(ntdb) == 0);
+		ok(!errors, "We had %u open errors", errors);
+
+		opened = false;
+		ntdb_close(ntdb);
+	}
+
+	return exit_status();
+}
diff --git a/lib/ntdb/test/run-57-die-during-transaction.c b/lib/ntdb/test/run-57-die-during-transaction.c
new file mode 100644
index 0000000000..98ec9dd63a
--- /dev/null
+++ b/lib/ntdb/test/run-57-die-during-transaction.c
@@ -0,0 +1,294 @@
+#include "private.h"
+#include <unistd.h>
+#include "lock-tracking.h"
+#include "tap-interface.h"
+#include <stdlib.h>
+#include <assert.h>
+static ssize_t pwrite_check(int fd, const void *buf, size_t count, off_t offset);
+static ssize_t write_check(int fd, const void *buf, size_t count);
+static int ftruncate_check(int fd, off_t length);
+
+#define pwrite pwrite_check
+#define write write_check
+#define fcntl fcntl_with_lockcheck
+#define ftruncate ftruncate_check
+
+/* There's a malloc inside transaction_setup_recovery, and valgrind complains
+ * when we longjmp and leak it. */
+#define MAX_ALLOCATIONS 10
+static void *allocated[MAX_ALLOCATIONS];
+static unsigned max_alloc = 0;
+
+static void *malloc_noleak(size_t len)
+{
+	unsigned int i;
+
+	for (i = 0; i < MAX_ALLOCATIONS; i++)
+		if (!allocated[i]) {
+			allocated[i] = malloc(len);
+			if (i > max_alloc) {
+				max_alloc = i;
+				diag("max_alloc: %i", max_alloc);
+			}
+			return allocated[i];
+		}
+	diag("Too many allocations!");
+	abort();
+}
+
+static void *realloc_noleak(void *p, size_t size)
+{
+	unsigned int i;
+
+	for (i = 0; i < MAX_ALLOCATIONS; i++) {
+		if (allocated[i] == p) {
+			if (i > max_alloc) {
+				max_alloc = i;
+				diag("max_alloc: %i", max_alloc);
+			}
+			return allocated[i] = realloc(p, size);
+		}
+	}
+	diag("Untracked realloc!");
+	abort();
+}
+
+static void free_noleak(void *p)
+{
+	unsigned int i;
+
+	/* We don't catch asprintf, so don't complain if we miss one. */
+	for (i = 0; i < MAX_ALLOCATIONS; i++) {
+		if (allocated[i] == p) {
+			allocated[i] = NULL;
+			break;
+		}
+	}
+	free(p);
+}
+
+static void free_all(void)
+{
+	unsigned int i;
+
+	for (i = 0; i < MAX_ALLOCATIONS; i++) {
+		free(allocated[i]);
+		allocated[i] = NULL;
+	}
+}
+
+#define malloc malloc_noleak
+#define free free_noleak
+#define realloc realloc_noleak
+
+#include "ntdb-source.h"
+
+#undef malloc
+#undef free
+#undef realloc
+#undef write
+#undef pwrite
+#undef fcntl
+#undef ftruncate
+
+#include <stdbool.h>
+#include <stdarg.h>
+#include <ccan/err/err.h>
+#include <setjmp.h>
+#include "external-agent.h"
+#include "logging.h"
+
+static bool in_transaction;
+static int target, current;
+static jmp_buf jmpbuf;
+#define TEST_DBNAME "run-57-die-during-transaction.ntdb"
+#define KEY_STRING "helloworld"
+
+static void maybe_die(int fd)
+{
+	if (in_transaction && current++ == target) {
+		longjmp(jmpbuf, 1);
+	}
+}
+
+static ssize_t pwrite_check(int fd,
+			    const void *buf, size_t count, off_t offset)
+{
+	ssize_t ret;
+
+	maybe_die(fd);
+
+	ret = pwrite(fd, buf, count, offset);
+	if (ret != count)
+		return ret;
+
+	maybe_die(fd);
+	return ret;
+}
+
+static ssize_t write_check(int fd, const void *buf, size_t count)
+{
+	ssize_t ret;
+
+	maybe_die(fd);
+
+	ret = write(fd, buf, count);
+	if (ret != count)
+		return ret;
+
+	maybe_die(fd);
+	return ret;
+}
+
+static int ftruncate_check(int fd, off_t length)
+{
+	int ret;
+
+	maybe_die(fd);
+
+	ret = ftruncate(fd, length);
+
+	maybe_die(fd);
+	return ret;
+}
+
+static bool test_death(enum operation op, struct agent *agent)
+{
+	struct ntdb_context *ntdb = NULL;
+	NTDB_DATA key;
+	enum agent_return ret;
+	int needed_recovery = 0;
+
+	current = target = 0;
+reset:
+	unlink(TEST_DBNAME);
+	ntdb = ntdb_open(TEST_DBNAME, NTDB_NOMMAP,
+		       O_CREAT|O_TRUNC|O_RDWR, 0600, &tap_log_attr);
+	if (!ntdb) {
+		diag("Failed opening NTDB: %s", strerror(errno));
+		return false;
+	}
+
+	if (setjmp(jmpbuf) != 0) {
+		/* We're partway through.  Simulate our death. */
+		close(ntdb->file->fd);
+		forget_locking();
+		in_transaction = false;
+
+		ret = external_agent_operation(agent, NEEDS_RECOVERY, "");
+		if (ret == SUCCESS)
+			needed_recovery++;
+		else if (ret != FAILED) {
+			diag("Step %u agent NEEDS_RECOVERY = %s", current,
+			     agent_return_name(ret));
+			return false;
+		}
+
+		ret = external_agent_operation(agent, op, KEY_STRING);
+		if (ret != SUCCESS) {
+			diag("Step %u op %s failed = %s", current,
+			     operation_name(op),
+			     agent_return_name(ret));
+			return false;
+		}
+
+		ret = external_agent_operation(agent, NEEDS_RECOVERY, "");
+		if (ret != FAILED) {
+			diag("Still needs recovery after step %u = %s",
+			     current, agent_return_name(ret));
+			return false;
+		}
+
+		ret = external_agent_operation(agent, CHECK, "");
+		if (ret != SUCCESS) {
+			diag("Step %u check failed = %s", current,
+			     agent_return_name(ret));
+			return false;
+		}
+
+		ret = external_agent_operation(agent, CLOSE, "");
+		if (ret != SUCCESS) {
+			diag("Step %u close failed = %s", current,
+			     agent_return_name(ret));
+			return false;
+		}
+
+		/* Suppress logging as this tries to use closed fd. */
+		suppress_logging = true;
+		suppress_lockcheck = true;
+		ntdb_close(ntdb);
+		suppress_logging = false;
+		suppress_lockcheck = false;
+		target++;
+		current = 0;
+		free_all();
+		goto reset;
+	}
+
+	/* Put key for agent to fetch. */
+	key = ntdb_mkdata(KEY_STRING, strlen(KEY_STRING));
+	if (ntdb_store(ntdb, key, key, NTDB_INSERT) != 0)
+		return false;
+
+	/* This is the key we insert in transaction. */
+	key.dsize--;
+
+	ret = external_agent_operation(agent, OPEN, TEST_DBNAME);
+	if (ret != SUCCESS)
+		errx(1, "Agent failed to open: %s", agent_return_name(ret));
+
+	ret = external_agent_operation(agent, FETCH, KEY_STRING);
+	if (ret != SUCCESS)
+		errx(1, "Agent failed find key: %s", agent_return_name(ret));
+
+	in_transaction = true;
+	if (ntdb_transaction_start(ntdb) != 0)
+		return false;
+
+	if (ntdb_store(ntdb, key, key, NTDB_INSERT) != 0)
+		return false;
+
+	if (ntdb_transaction_commit(ntdb) != 0)
+		return false;
+
+	in_transaction = false;
+
+	/* We made it! */
+	diag("Completed %u runs", current);
+	ntdb_close(ntdb);
+	ret = external_agent_operation(agent, CLOSE, "");
+	if (ret != SUCCESS) {
+		diag("Step %u close failed = %s", current,
+		     agent_return_name(ret));
+		return false;
+	}
+
+	ok1(needed_recovery);
+	ok1(locking_errors == 0);
+	ok1(forget_locking() == 0);
+	locking_errors = 0;
+	return true;
+}
+
+int main(int argc, char *argv[])
+{
+	enum operation ops[] = { FETCH, STORE, TRANSACTION_START };
+	struct agent *agent;
+	int i;
+
+	plan_tests(12);
+	unlock_callback = maybe_die;
+
+	external_agent_free = free_noleak;
+	agent = prepare_external_agent();
+	if (!agent)
+		err(1, "preparing agent");
+
+	for (i = 0; i < sizeof(ops)/sizeof(ops[0]); i++) {
+		diag("Testing %s after death", operation_name(ops[i]));
+		ok1(test_death(ops[i], agent));
+	}
+
+	free_external_agent(agent);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/run-64-bit-tdb.c b/lib/ntdb/test/run-64-bit-tdb.c
new file mode 100644
index 0000000000..6a146cb1cf
--- /dev/null
+++ b/lib/ntdb/test/run-64-bit-tdb.c
@@ -0,0 +1,72 @@
+#include "ntdb-source.h"
+#include "tap-interface.h"
+#include "logging.h"
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT };
+
+	if (sizeof(off_t) <= 4) {
+		plan_tests(1);
+		pass("No 64 bit off_t");
+		return exit_status();
+	}
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 14);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		off_t old_size;
+		NTDB_DATA k, d;
+		struct hash_info h;
+		struct ntdb_used_record rec;
+		ntdb_off_t off;
+
+		ntdb = ntdb_open("run-64-bit-ntdb.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		ok1(ntdb);
+		if (!ntdb)
+			continue;
+
+		old_size = ntdb->file->map_size;
+
+		/* This makes a sparse file */
+		ok1(ftruncate(ntdb->file->fd, 0xFFFFFFF0) == 0);
+		ok1(add_free_record(ntdb, old_size, 0xFFFFFFF0 - old_size,
+				    NTDB_LOCK_WAIT, false) == NTDB_SUCCESS);
+
+		/* Now add a little record past the 4G barrier. */
+		ok1(ntdb_expand_file(ntdb, 100) == NTDB_SUCCESS);
+		ok1(add_free_record(ntdb, 0xFFFFFFF0, 100, NTDB_LOCK_WAIT, false)
+		    == NTDB_SUCCESS);
+
+		ok1(ntdb_check(ntdb, NULL, NULL) == NTDB_SUCCESS);
+
+		/* Test allocation path. */
+		k = ntdb_mkdata("key", 4);
+		d = ntdb_mkdata("data", 5);
+		ok1(ntdb_store(ntdb, k, d, NTDB_INSERT) == 0);
+		ok1(ntdb_check(ntdb, NULL, NULL) == NTDB_SUCCESS);
+
+		/* Make sure it put it at end as we expected. */
+		off = find_and_lock(ntdb, k, F_RDLCK, &h, &rec, NULL);
+		ok1(off >= 0xFFFFFFF0);
+		ntdb_unlock_hashes(ntdb, h.hlock_start, h.hlock_range, F_RDLCK);
+
+		ok1(ntdb_fetch(ntdb, k, &d) == 0);
+		ok1(d.dsize == 5);
+		ok1(strcmp((char *)d.dptr, "data") == 0);
+		free(d.dptr);
+
+		ok1(ntdb_delete(ntdb, k) == 0);
+		ok1(ntdb_check(ntdb, NULL, NULL) == NTDB_SUCCESS);
+
+		ntdb_close(ntdb);
+	}
+
+	/* We might get messages about mmap failing, so don't test
+	 * tap_log_messages */
+	return exit_status();
+}
diff --git a/lib/ntdb/test/run-90-get-set-attributes.c b/lib/ntdb/test/run-90-get-set-attributes.c
new file mode 100644
index 0000000000..fc265b0729
--- /dev/null
+++ b/lib/ntdb/test/run-90-get-set-attributes.c
@@ -0,0 +1,159 @@
+#include "ntdb-source.h"
+#include "tap-interface.h"
+#include "logging.h"
+
+static int mylock(int fd, int rw, off_t off, off_t len, bool waitflag,
+		  void *unused)
+{
+	return 0;
+}
+
+static int myunlock(int fd, int rw, off_t off, off_t len, void *unused)
+{
+	return 0;
+}
+
+static uint64_t hash_fn(const void *key, size_t len, uint64_t seed,
+			void *priv)
+{
+	return 0;
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_CONVERT, NTDB_NOMMAP|NTDB_CONVERT };
+	union ntdb_attribute seed_attr;
+	union ntdb_attribute hash_attr;
+	union ntdb_attribute lock_attr;
+
+	seed_attr.base.attr = NTDB_ATTRIBUTE_SEED;
+	seed_attr.base.next = &hash_attr;
+	seed_attr.seed.seed = 100;
+
+	hash_attr.base.attr = NTDB_ATTRIBUTE_HASH;
+	hash_attr.base.next = &lock_attr;
+	hash_attr.hash.fn = hash_fn;
+	hash_attr.hash.data = &hash_attr;
+
+	lock_attr.base.attr = NTDB_ATTRIBUTE_FLOCK;
+	lock_attr.base.next = &tap_log_attr;
+	lock_attr.flock.lock = mylock;
+	lock_attr.flock.unlock = myunlock;
+	lock_attr.flock.data = &lock_attr;
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 50);
+
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		union ntdb_attribute attr;
+
+		/* First open with no attributes. */
+		ntdb = ntdb_open("run-90-get-set-attributes.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, NULL);
+		ok1(ntdb);
+
+		/* Get log on no attributes will fail */
+		attr.base.attr = NTDB_ATTRIBUTE_LOG;
+		ok1(ntdb_get_attribute(ntdb, &attr) == NTDB_ERR_NOEXIST);
+		/* These always work. */
+		attr.base.attr = NTDB_ATTRIBUTE_HASH;
+		ok1(ntdb_get_attribute(ntdb, &attr) == 0);
+		ok1(attr.base.attr == NTDB_ATTRIBUTE_HASH);
+		ok1(attr.hash.fn == ntdb_jenkins_hash);
+		attr.base.attr = NTDB_ATTRIBUTE_FLOCK;
+		ok1(ntdb_get_attribute(ntdb, &attr) == 0);
+		ok1(attr.base.attr == NTDB_ATTRIBUTE_FLOCK);
+		ok1(attr.flock.lock == ntdb_fcntl_lock);
+		ok1(attr.flock.unlock == ntdb_fcntl_unlock);
+		attr.base.attr = NTDB_ATTRIBUTE_SEED;
+		ok1(ntdb_get_attribute(ntdb, &attr) == 0);
+		ok1(attr.base.attr == NTDB_ATTRIBUTE_SEED);
+		/* This is possible, just astronomically unlikely. */
+		ok1(attr.seed.seed != 0);
+
+		/* Unset attributes. */
+		ntdb_unset_attribute(ntdb, NTDB_ATTRIBUTE_LOG);
+		ntdb_unset_attribute(ntdb, NTDB_ATTRIBUTE_FLOCK);
+
+		/* Set them. */
+		ok1(ntdb_set_attribute(ntdb, &tap_log_attr) == 0);
+		ok1(ntdb_set_attribute(ntdb, &lock_attr) == 0);
+		/* These should fail. */
+		ok1(ntdb_set_attribute(ntdb, &seed_attr) == NTDB_ERR_EINVAL);
+		ok1(tap_log_messages == 1);
+		ok1(ntdb_set_attribute(ntdb, &hash_attr) == NTDB_ERR_EINVAL);
+		ok1(tap_log_messages == 2);
+		tap_log_messages = 0;
+
+		/* Getting them should work as expected. */
+		attr.base.attr = NTDB_ATTRIBUTE_LOG;
+		ok1(ntdb_get_attribute(ntdb, &attr) == 0);
+		ok1(attr.base.attr == NTDB_ATTRIBUTE_LOG);
+		ok1(attr.log.fn == tap_log_attr.log.fn);
+		ok1(attr.log.data == tap_log_attr.log.data);
+
+		attr.base.attr = NTDB_ATTRIBUTE_FLOCK;
+		ok1(ntdb_get_attribute(ntdb, &attr) == 0);
+		ok1(attr.base.attr == NTDB_ATTRIBUTE_FLOCK);
+		ok1(attr.flock.lock == mylock);
+		ok1(attr.flock.unlock == myunlock);
+		ok1(attr.flock.data == &lock_attr);
+
+		/* Unset them again. */
+		ntdb_unset_attribute(ntdb, NTDB_ATTRIBUTE_FLOCK);
+		ok1(tap_log_messages == 0);
+		ntdb_unset_attribute(ntdb, NTDB_ATTRIBUTE_LOG);
+		ok1(tap_log_messages == 0);
+
+		ntdb_close(ntdb);
+		ok1(tap_log_messages == 0);
+
+		/* Now open with all attributes. */
+		ntdb = ntdb_open("run-90-get-set-attributes.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600,
+			       &seed_attr);
+
+		ok1(ntdb);
+
+		/* Get will succeed */
+		attr.base.attr = NTDB_ATTRIBUTE_LOG;
+		ok1(ntdb_get_attribute(ntdb, &attr) == 0);
+		ok1(attr.base.attr == NTDB_ATTRIBUTE_LOG);
+		ok1(attr.log.fn == tap_log_attr.log.fn);
+		ok1(attr.log.data == tap_log_attr.log.data);
+
+		attr.base.attr = NTDB_ATTRIBUTE_HASH;
+		ok1(ntdb_get_attribute(ntdb, &attr) == 0);
+		ok1(attr.base.attr == NTDB_ATTRIBUTE_HASH);
+		ok1(attr.hash.fn == hash_fn);
+		ok1(attr.hash.data == &hash_attr);
+
+		attr.base.attr = NTDB_ATTRIBUTE_FLOCK;
+		ok1(ntdb_get_attribute(ntdb, &attr) == 0);
+		ok1(attr.base.attr == NTDB_ATTRIBUTE_FLOCK);
+		ok1(attr.flock.lock == mylock);
+		ok1(attr.flock.unlock == myunlock);
+		ok1(attr.flock.data == &lock_attr);
+
+		attr.base.attr = NTDB_ATTRIBUTE_SEED;
+		ok1(ntdb_get_attribute(ntdb, &attr) == 0);
+		ok1(attr.base.attr == NTDB_ATTRIBUTE_SEED);
+		ok1(attr.seed.seed == seed_attr.seed.seed);
+
+		/* Unset attributes. */
+		ntdb_unset_attribute(ntdb, NTDB_ATTRIBUTE_HASH);
+		ok1(tap_log_messages == 1);
+		ntdb_unset_attribute(ntdb, NTDB_ATTRIBUTE_SEED);
+		ok1(tap_log_messages == 2);
+		ntdb_unset_attribute(ntdb, NTDB_ATTRIBUTE_FLOCK);
+		ntdb_unset_attribute(ntdb, NTDB_ATTRIBUTE_LOG);
+		ok1(tap_log_messages == 2);
+		tap_log_messages = 0;
+
+		ntdb_close(ntdb);
+
+	}
+	return exit_status();
+}
diff --git a/lib/ntdb/test/run-capabilities.c b/lib/ntdb/test/run-capabilities.c
new file mode 100644
index 0000000000..c2c6aa15db
--- /dev/null
+++ b/lib/ntdb/test/run-capabilities.c
@@ -0,0 +1,271 @@
+#include <ccan/failtest/failtest_override.h>
+#include "ntdb-source.h"
+#include "tap-interface.h"
+#include "logging.h"
+#include "layout.h"
+#include "failtest_helper.h"
+#include <stdarg.h>
+
+static size_t len_of(bool breaks_check, bool breaks_write, bool breaks_open)
+{
+	size_t len = 0;
+	if (breaks_check)
+		len += 8;
+	if (breaks_write)
+		len += 16;
+	if (breaks_open)
+		len += 32;
+	return len;
+}
+
+/* Creates a NTDB with various capabilities. */
+static void create_ntdb(const char *name,
+		       unsigned int cap,
+		       bool breaks_check,
+		       bool breaks_write,
+		       bool breaks_open, ...)
+{
+	NTDB_DATA key, data;
+	va_list ap;
+	struct ntdb_layout *layout;
+	struct ntdb_context *ntdb;
+	int fd;
+
+	key = ntdb_mkdata("Hello", 5);
+	data = ntdb_mkdata("world", 5);
+
+	/* Create a NTDB with some data, and some capabilities */
+	layout = new_ntdb_layout();
+	ntdb_layout_add_freetable(layout);
+	ntdb_layout_add_used(layout, key, data, 6);
+	ntdb_layout_add_free(layout, 80, 0);
+	ntdb_layout_add_capability(layout, cap,
+				  breaks_write, breaks_check, breaks_open,
+				  len_of(breaks_check, breaks_write, breaks_open));
+
+	va_start(ap, breaks_open);
+	while ((cap = va_arg(ap, int)) != 0) {
+		breaks_check = va_arg(ap, int);
+		breaks_write = va_arg(ap, int);
+		breaks_open = va_arg(ap, int);
+
+		key.dsize--;
+		ntdb_layout_add_used(layout, key, data, 11 - key.dsize);
+		ntdb_layout_add_free(layout, 80, 0);
+		ntdb_layout_add_capability(layout, cap,
+					  breaks_write, breaks_check,
+					  breaks_open,
+					  len_of(breaks_check, breaks_write,
+						 breaks_open));
+	}
+	va_end(ap);
+
+	/* We open-code this, because we need to use the failtest write. */
+	ntdb = ntdb_layout_get(layout, failtest_free, &tap_log_attr);
+
+	fd = open(name, O_RDWR|O_TRUNC|O_CREAT, 0600);
+	if (fd < 0)
+		err(1, "opening %s for writing", name);
+	if (write(fd, ntdb->file->map_ptr, ntdb->file->map_size)
+	    != ntdb->file->map_size)
+		err(1, "writing %s", name);
+	close(fd);
+	ntdb_close(ntdb);
+	ntdb_layout_free(layout);
+}
+
+/* Note all the "goto out" early exits: they're to shorten failtest time. */
+int main(int argc, char *argv[])
+{
+	struct ntdb_context *ntdb;
+	char *summary;
+
+	failtest_init(argc, argv);
+	failtest_hook = block_repeat_failures;
+	failtest_exit_check = exit_check_log;
+	plan_tests(60);
+
+	failtest_suppress = true;
+	/* Capability says you can ignore it? */
+	create_ntdb("run-capabilities.ntdb", 1, false, false, false, 0);
+
+	failtest_suppress = false;
+	ntdb = ntdb_open("run-capabilities.ntdb", NTDB_DEFAULT, O_RDWR, 0,
+		       &tap_log_attr);
+	failtest_suppress = true;
+	if (!ok1(ntdb))
+		goto out;
+	ok1(tap_log_messages == 0);
+	ok1(ntdb_check(ntdb, NULL, NULL) == NTDB_SUCCESS);
+	ok1(tap_log_messages == 0);
+	ntdb_close(ntdb);
+
+	/* Two capabilitues say you can ignore them? */
+	create_ntdb("run-capabilities.ntdb",
+		   1, false, false, false,
+		   2, false, false, false, 0);
+
+	failtest_suppress = false;
+	ntdb = ntdb_open("run-capabilities.ntdb", NTDB_DEFAULT, O_RDWR, 0,
+		       &tap_log_attr);
+	failtest_suppress = true;
+	if (!ok1(ntdb))
+		goto out;
+	ok1(tap_log_messages == 0);
+	ok1(ntdb_check(ntdb, NULL, NULL) == NTDB_SUCCESS);
+	ok1(tap_log_messages == 0);
+	ok1(ntdb_summary(ntdb, 0, &summary) == NTDB_SUCCESS);
+	ok1(strstr(summary, "Capability 1\n"));
+	free(summary);
+	ntdb_close(ntdb);
+
+	/* Capability says you can't check. */
+	create_ntdb("run-capabilities.ntdb",
+		   1, false, false, false,
+		   2, true, false, false, 0);
+
+	failtest_suppress = false;
+	ntdb = ntdb_open("run-capabilities.ntdb", NTDB_DEFAULT, O_RDWR, 0,
+		       &tap_log_attr);
+	failtest_suppress = true;
+	if (!ok1(ntdb))
+		goto out;
+	ok1(tap_log_messages == 0);
+	ok1(ntdb_get_flags(ntdb) & NTDB_CANT_CHECK);
+	ok1(ntdb_check(ntdb, NULL, NULL) == NTDB_SUCCESS);
+	/* We expect a warning! */
+	ok1(tap_log_messages == 1);
+	ok1(strstr(log_last, "capabilit"));
+	ok1(ntdb_summary(ntdb, 0, &summary) == NTDB_SUCCESS);
+	ok1(strstr(summary, "Capability 1\n"));
+	ok1(strstr(summary, "Capability 2 (uncheckable)\n"));
+	free(summary);
+	ntdb_close(ntdb);
+
+	/* Capability says you can't write. */
+	create_ntdb("run-capabilities.ntdb",
+		   1, false, false, false,
+		   2, false, true, false, 0);
+
+	failtest_suppress = false;
+	ntdb = ntdb_open("run-capabilities.ntdb", NTDB_DEFAULT, O_RDWR, 0,
+		       &tap_log_attr);
+	failtest_suppress = true;
+	/* We expect a message. */
+	ok1(!ntdb);
+	if (!ok1(tap_log_messages == 2))
+		goto out;
+	if (!ok1(strstr(log_last, "unknown")))
+		goto out;
+	ok1(strstr(log_last, "write"));
+
+	/* We can open it read-only though! */
+	failtest_suppress = false;
+	ntdb = ntdb_open("run-capabilities.ntdb", NTDB_DEFAULT, O_RDONLY, 0,
+		       &tap_log_attr);
+	failtest_suppress = true;
+	if (!ok1(ntdb))
+		goto out;
+	ok1(tap_log_messages == 2);
+	ok1(ntdb_check(ntdb, NULL, NULL) == NTDB_SUCCESS);
+	ok1(tap_log_messages == 2);
+	ok1(ntdb_summary(ntdb, 0, &summary) == NTDB_SUCCESS);
+	ok1(strstr(summary, "Capability 1\n"));
+	ok1(strstr(summary, "Capability 2 (read-only)\n"));
+	free(summary);
+	ntdb_close(ntdb);
+
+	/* Capability says you can't open. */
+	create_ntdb("run-capabilities.ntdb",
+		   1, false, false, false,
+		   2, false, false, true, 0);
+
+	failtest_suppress = false;
+	ntdb = ntdb_open("run-capabilities.ntdb", NTDB_DEFAULT, O_RDWR, 0,
+		       &tap_log_attr);
+	failtest_suppress = true;
+	/* We expect a message. */
+	ok1(!ntdb);
+	if (!ok1(tap_log_messages == 3))
+		goto out;
+	if (!ok1(strstr(log_last, "unknown")))
+		goto out;
+
+	/* Combine capabilities correctly. */
+	create_ntdb("run-capabilities.ntdb",
+		   1, false, false, false,
+		   2, true, false, false,
+		   3, false, true, false, 0);
+
+	failtest_suppress = false;
+	ntdb = ntdb_open("run-capabilities.ntdb", NTDB_DEFAULT, O_RDWR, 0,
+		       &tap_log_attr);
+	failtest_suppress = true;
+	/* We expect a message. */
+	ok1(!ntdb);
+	if (!ok1(tap_log_messages == 4))
+		goto out;
+	if (!ok1(strstr(log_last, "unknown")))
+		goto out;
+	ok1(strstr(log_last, "write"));
+
+	/* We can open it read-only though! */
+	failtest_suppress = false;
+	ntdb = ntdb_open("run-capabilities.ntdb", NTDB_DEFAULT, O_RDONLY, 0,
+		       &tap_log_attr);
+	failtest_suppress = true;
+	if (!ok1(ntdb))
+		goto out;
+	ok1(tap_log_messages == 4);
+	ok1(ntdb_get_flags(ntdb) & NTDB_CANT_CHECK);
+	ok1(ntdb_check(ntdb, NULL, NULL) == NTDB_SUCCESS);
+	/* We expect a warning! */
+	ok1(tap_log_messages == 5);
+	ok1(strstr(log_last, "unknown"));
+	ok1(ntdb_summary(ntdb, 0, &summary) == NTDB_SUCCESS);
+	ok1(strstr(summary, "Capability 1\n"));
+	ok1(strstr(summary, "Capability 2 (uncheckable)\n"));
+	ok1(strstr(summary, "Capability 3 (read-only)\n"));
+	free(summary);
+	ntdb_close(ntdb);
+
+	/* Two capability flags in one. */
+	create_ntdb("run-capabilities.ntdb",
+		   1, false, false, false,
+		   2, true, true, false,
+		   0);
+
+	failtest_suppress = false;
+	ntdb = ntdb_open("run-capabilities.ntdb", NTDB_DEFAULT, O_RDWR, 0,
+		       &tap_log_attr);
+	failtest_suppress = true;
+	/* We expect a message. */
+	ok1(!ntdb);
+	if (!ok1(tap_log_messages == 6))
+		goto out;
+	if (!ok1(strstr(log_last, "unknown")))
+		goto out;
+	ok1(strstr(log_last, "write"));
+
+	/* We can open it read-only though! */
+	failtest_suppress = false;
+	ntdb = ntdb_open("run-capabilities.ntdb", NTDB_DEFAULT, O_RDONLY, 0,
+		       &tap_log_attr);
+	failtest_suppress = true;
+	if (!ok1(ntdb))
+		goto out;
+	ok1(tap_log_messages == 6);
+	ok1(ntdb_get_flags(ntdb) & NTDB_CANT_CHECK);
+	ok1(ntdb_check(ntdb, NULL, NULL) == NTDB_SUCCESS);
+	/* We expect a warning! */
+	ok1(tap_log_messages == 7);
+	ok1(strstr(log_last, "unknown"));
+	ok1(ntdb_summary(ntdb, 0, &summary) == NTDB_SUCCESS);
+	ok1(strstr(summary, "Capability 1\n"));
+	ok1(strstr(summary, "Capability 2 (uncheckable,read-only)\n"));
+	free(summary);
+	ntdb_close(ntdb);
+
+out:
+	failtest_exit(exit_status());
+}
diff --git a/lib/ntdb/test/run-expand-in-transaction.c b/lib/ntdb/test/run-expand-in-transaction.c
new file mode 100644
index 0000000000..dadbec7922
--- /dev/null
+++ b/lib/ntdb/test/run-expand-in-transaction.c
@@ -0,0 +1,36 @@
+#include "ntdb-source.h"
+#include "tap-interface.h"
+#include "logging.h"
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_CONVERT, NTDB_NOMMAP|NTDB_CONVERT };
+	NTDB_DATA key = ntdb_mkdata("key", 3);
+	NTDB_DATA data = ntdb_mkdata("data", 4);
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 7 + 1);
+
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		size_t size;
+		ntdb = ntdb_open("run-expand-in-transaction.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		ok1(ntdb);
+		if (!ntdb)
+			continue;
+
+		size = ntdb->file->map_size;
+		ok1(ntdb_transaction_start(ntdb) == 0);
+		ok1(ntdb_store(ntdb, key, data, NTDB_INSERT) == 0);
+		ok1(ntdb->file->map_size > size);
+		ok1(ntdb_transaction_commit(ntdb) == 0);
+		ok1(ntdb->file->map_size > size);
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+		ntdb_close(ntdb);
+	}
+
+	ok1(tap_log_messages == 0);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/run-features.c b/lib/ntdb/test/run-features.c
new file mode 100644
index 0000000000..0d6b3bce76
--- /dev/null
+++ b/lib/ntdb/test/run-features.c
@@ -0,0 +1,62 @@
+#include "ntdb-source.h"
+#include "tap-interface.h"
+#include "logging.h"
+
+int main(int argc, char *argv[])
+{
+	unsigned int i, j;
+	struct ntdb_context *ntdb;
+	int flags[] = { NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_CONVERT, NTDB_NOMMAP|NTDB_CONVERT };
+	NTDB_DATA key = { (unsigned char *)&j, sizeof(j) };
+	NTDB_DATA data = { (unsigned char *)&j, sizeof(j) };
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 8 + 1);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		uint64_t features;
+		ntdb = ntdb_open("run-features.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		ok1(ntdb);
+		if (!ntdb)
+			continue;
+
+		/* Put some stuff in there. */
+		for (j = 0; j < 100; j++) {
+			if (ntdb_store(ntdb, key, data, NTDB_REPLACE) != 0)
+				fail("Storing in ntdb");
+		}
+
+		/* Mess with features fields in hdr. */
+		features = (~NTDB_FEATURE_MASK ^ 1);
+		ok1(ntdb_write_convert(ntdb, offsetof(struct ntdb_header,
+						    features_used),
+				      &features, sizeof(features)) == 0);
+		ok1(ntdb_write_convert(ntdb, offsetof(struct ntdb_header,
+						    features_offered),
+				      &features, sizeof(features)) == 0);
+		ntdb_close(ntdb);
+
+		ntdb = ntdb_open("run-features.ntdb", flags[i], O_RDWR, 0,
+			       &tap_log_attr);
+		ok1(ntdb);
+		if (!ntdb)
+			continue;
+
+		/* Should not have changed features offered. */
+		ok1(ntdb_read_convert(ntdb, offsetof(struct ntdb_header,
+						   features_offered),
+				     &features, sizeof(features)) == 0);
+		ok1(features == (~NTDB_FEATURE_MASK ^ 1));
+
+		/* Should have cleared unknown bits in features_used. */
+		ok1(ntdb_read_convert(ntdb, offsetof(struct ntdb_header,
+						   features_used),
+				     &features, sizeof(features)) == 0);
+		ok1(features == (1 & NTDB_FEATURE_MASK));
+
+		ntdb_close(ntdb);
+	}
+
+	ok1(tap_log_messages == 0);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/run-lockall.c b/lib/ntdb/test/run-lockall.c
new file mode 100644
index 0000000000..964164e20b
--- /dev/null
+++ b/lib/ntdb/test/run-lockall.c
@@ -0,0 +1,70 @@
+#include "private.h"
+#include <unistd.h>
+#include "lock-tracking.h"
+
+#define fcntl fcntl_with_lockcheck
+#include "ntdb-source.h"
+
+#include "tap-interface.h"
+#include <stdlib.h>
+#include <stdbool.h>
+#include <stdarg.h>
+#include "external-agent.h"
+#include "logging.h"
+
+#define TEST_DBNAME "run-lockall.ntdb"
+
+#undef fcntl
+
+int main(int argc, char *argv[])
+{
+	struct agent *agent;
+	int flags[] = { NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_CONVERT, NTDB_NOMMAP|NTDB_CONVERT };
+	int i;
+
+	plan_tests(13 * sizeof(flags)/sizeof(flags[0]) + 1);
+	agent = prepare_external_agent();
+	if (!agent)
+		err(1, "preparing agent");
+
+	for (i = 0; i < sizeof(flags)/sizeof(flags[0]); i++) {
+		enum agent_return ret;
+		struct ntdb_context *ntdb;
+
+		ntdb = ntdb_open(TEST_DBNAME, flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		ok1(ntdb);
+
+		ret = external_agent_operation(agent, OPEN, TEST_DBNAME);
+		ok1(ret == SUCCESS);
+
+		ok1(ntdb_lockall(ntdb) == NTDB_SUCCESS);
+		ok1(external_agent_operation(agent, STORE, "key")
+		    == WOULD_HAVE_BLOCKED);
+		ok1(external_agent_operation(agent, FETCH, "key")
+		    == WOULD_HAVE_BLOCKED);
+		/* Test nesting. */
+		ok1(ntdb_lockall(ntdb) == NTDB_SUCCESS);
+		ntdb_unlockall(ntdb);
+		ntdb_unlockall(ntdb);
+
+		ok1(external_agent_operation(agent, STORE, "key") == SUCCESS);
+
+		ok1(ntdb_lockall_read(ntdb) == NTDB_SUCCESS);
+		ok1(external_agent_operation(agent, STORE, "key")
+		    == WOULD_HAVE_BLOCKED);
+		ok1(external_agent_operation(agent, FETCH, "key") == SUCCESS);
+		ok1(ntdb_lockall_read(ntdb) == NTDB_SUCCESS);
+		ntdb_unlockall_read(ntdb);
+		ntdb_unlockall_read(ntdb);
+
+		ok1(external_agent_operation(agent, STORE, "key") == SUCCESS);
+		ok1(external_agent_operation(agent, CLOSE, NULL) == SUCCESS);
+		ntdb_close(ntdb);
+	}
+
+	free_external_agent(agent);
+	ok1(tap_log_messages == 0);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/run-remap-in-read_traverse.c b/lib/ntdb/test/run-remap-in-read_traverse.c
new file mode 100644
index 0000000000..2d817c2d73
--- /dev/null
+++ b/lib/ntdb/test/run-remap-in-read_traverse.c
@@ -0,0 +1,57 @@
+#include "ntdb-source.h"
+/* We had a bug where we marked the ntdb read-only for a ntdb_traverse_read.
+ * If we then expanded the ntdb, we would remap read-only, and later SEGV. */
+#include "tap-interface.h"
+#include "external-agent.h"
+#include "logging.h"
+
+static bool file_larger(int fd, ntdb_len_t size)
+{
+	struct stat st;
+
+	fstat(fd, &st);
+	return st.st_size != size;
+}
+
+static unsigned add_records_to_grow(struct agent *agent, int fd, ntdb_len_t size)
+{
+	unsigned int i;
+
+	for (i = 0; !file_larger(fd, size); i++) {
+		char data[20];
+		sprintf(data, "%i", i);
+		if (external_agent_operation(agent, STORE, data) != SUCCESS)
+			return 0;
+	}
+	diag("Added %u records to grow file", i);
+	return i;
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct agent *agent;
+	struct ntdb_context *ntdb;
+	NTDB_DATA d = ntdb_mkdata("hello", 5);
+	const char filename[] = "run-remap-in-read_traverse.ntdb";
+
+	plan_tests(4);
+
+	agent = prepare_external_agent();
+
+	ntdb = ntdb_open(filename, NTDB_DEFAULT,
+		       O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+
+	ok1(external_agent_operation(agent, OPEN, filename) == SUCCESS);
+	i = add_records_to_grow(agent, ntdb->file->fd, ntdb->file->map_size);
+
+	/* Do a traverse. */
+	ok1(ntdb_traverse(ntdb, NULL, NULL) == i);
+
+	/* Now store something! */
+	ok1(ntdb_store(ntdb, d, d, NTDB_INSERT) == 0);
+	ok1(tap_log_messages == 0);
+	ntdb_close(ntdb);
+	free_external_agent(agent);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/run-seed.c b/lib/ntdb/test/run-seed.c
new file mode 100644
index 0000000000..2514f728ac
--- /dev/null
+++ b/lib/ntdb/test/run-seed.c
@@ -0,0 +1,61 @@
+#include "ntdb-source.h"
+#include "tap-interface.h"
+#include "logging.h"
+
+static int log_count = 0;
+
+/* Normally we get a log when setting random seed. */
+static void my_log_fn(struct ntdb_context *ntdb,
+		      enum ntdb_log_level level,
+		      enum NTDB_ERROR ecode,
+		      const char *message, void *priv)
+{
+	log_count++;
+}
+
+static union ntdb_attribute log_attr = {
+	.log = { .base = { .attr = NTDB_ATTRIBUTE_LOG },
+		 .fn = my_log_fn }
+};
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct ntdb_context *ntdb;
+	union ntdb_attribute attr;
+	int flags[] = { NTDB_INTERNAL, NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_INTERNAL|NTDB_CONVERT, NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT };
+
+	attr.seed.base.attr = NTDB_ATTRIBUTE_SEED;
+	attr.seed.base.next = &log_attr;
+	attr.seed.seed = 42;
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 4 + 4 * 3);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		struct ntdb_header hdr;
+		int fd;
+		ntdb = ntdb_open("run-seed.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &attr);
+		ok1(ntdb);
+		if (!ntdb)
+			continue;
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+		ok1(ntdb->hash_seed == 42);
+		ok1(log_count == 0);
+		ntdb_close(ntdb);
+
+		if (flags[i] & NTDB_INTERNAL)
+			continue;
+
+		fd = open("run-seed.ntdb", O_RDONLY);
+		ok1(fd >= 0);
+		ok1(read(fd, &hdr, sizeof(hdr)) == sizeof(hdr));
+		if (flags[i] & NTDB_CONVERT)
+			ok1(bswap_64(hdr.hash_seed) == 42);
+		else
+			ok1(hdr.hash_seed == 42);
+		close(fd);
+	}
+	return exit_status();
+}
diff --git a/lib/ntdb/test/run-tdb_errorstr.c b/lib/ntdb/test/run-tdb_errorstr.c
new file mode 100644
index 0000000000..5b023140a7
--- /dev/null
+++ b/lib/ntdb/test/run-tdb_errorstr.c
@@ -0,0 +1,52 @@
+#include "ntdb-source.h"
+#include "tap-interface.h"
+
+int main(int argc, char *argv[])
+{
+	enum NTDB_ERROR e;
+	plan_tests(NTDB_ERR_RDONLY*-1 + 2);
+
+	for (e = NTDB_SUCCESS; e >= NTDB_ERR_RDONLY; e--) {
+		switch (e) {
+		case NTDB_SUCCESS:
+			ok1(!strcmp(ntdb_errorstr(e),
+				    "Success"));
+			break;
+		case NTDB_ERR_IO:
+			ok1(!strcmp(ntdb_errorstr(e),
+				    "IO Error"));
+			break;
+		case NTDB_ERR_LOCK:
+			ok1(!strcmp(ntdb_errorstr(e),
+				    "Locking error"));
+			break;
+		case NTDB_ERR_OOM:
+			ok1(!strcmp(ntdb_errorstr(e),
+				    "Out of memory"));
+			break;
+		case NTDB_ERR_EXISTS:
+			ok1(!strcmp(ntdb_errorstr(e),
+				    "Record exists"));
+			break;
+		case NTDB_ERR_EINVAL:
+			ok1(!strcmp(ntdb_errorstr(e),
+				    "Invalid parameter"));
+			break;
+		case NTDB_ERR_NOEXIST:
+			ok1(!strcmp(ntdb_errorstr(e),
+				    "Record does not exist"));
+			break;
+		case NTDB_ERR_RDONLY:
+			ok1(!strcmp(ntdb_errorstr(e),
+				    "write not permitted"));
+			break;
+		case NTDB_ERR_CORRUPT:
+			ok1(!strcmp(ntdb_errorstr(e),
+				    "Corrupt database"));
+			break;
+		}
+	}
+	ok1(!strcmp(ntdb_errorstr(e), "Invalid error code"));
+
+	return exit_status();
+}
diff --git a/lib/ntdb/test/run-tdb_foreach.c b/lib/ntdb/test/run-tdb_foreach.c
new file mode 100644
index 0000000000..f1a2d00919
--- /dev/null
+++ b/lib/ntdb/test/run-tdb_foreach.c
@@ -0,0 +1,86 @@
+#include "ntdb-source.h"
+#include "tap-interface.h"
+#include "logging.h"
+
+static int drop_count(struct ntdb_context *ntdb, unsigned int *count)
+{
+	if (--(*count) == 0)
+		return 1;
+	return 0;
+}
+
+static int set_found(struct ntdb_context *ntdb, bool found[3])
+{
+	unsigned int idx;
+
+	if (strcmp(ntdb_name(ntdb), "run-ntdb_foreach0.ntdb") == 0)
+		idx = 0;
+	else if (strcmp(ntdb_name(ntdb), "run-ntdb_foreach1.ntdb") == 0)
+		idx = 1;
+	else if (strcmp(ntdb_name(ntdb), "run-ntdb_foreach2.ntdb") == 0)
+		idx = 2;
+	else
+		abort();
+
+	if (found[idx])
+		abort();
+	found[idx] = true;
+	return 0;
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i, count;
+	bool found[3];
+	struct ntdb_context *ntdb0, *ntdb1, *ntdb;
+	int flags[] = { NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_CONVERT, NTDB_NOMMAP|NTDB_CONVERT };
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 8);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb0 = ntdb_open("run-ntdb_foreach0.ntdb", flags[i],
+				O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		ntdb1 = ntdb_open("run-ntdb_foreach1.ntdb", flags[i],
+				O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+		ntdb = ntdb_open("run-ntdb_foreach2.ntdb", flags[i],
+				O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+
+		memset(found, 0, sizeof(found));
+		ntdb_foreach(set_found, found);
+		ok1(found[0] && found[1] && found[2]);
+
+		/* Test premature iteration termination */
+		count = 1;
+		ntdb_foreach(drop_count, &count);
+		ok1(count == 0);
+
+		ntdb_close(ntdb1);
+		memset(found, 0, sizeof(found));
+		ntdb_foreach(set_found, found);
+		ok1(found[0] && !found[1] && found[2]);
+
+		ntdb_close(ntdb);
+		memset(found, 0, sizeof(found));
+		ntdb_foreach(set_found, found);
+		ok1(found[0] && !found[1] && !found[2]);
+
+		ntdb1 = ntdb_open("run-ntdb_foreach1.ntdb", flags[i],
+				O_RDWR, 0600, &tap_log_attr);
+		memset(found, 0, sizeof(found));
+		ntdb_foreach(set_found, found);
+		ok1(found[0] && found[1] && !found[2]);
+
+		ntdb_close(ntdb0);
+		memset(found, 0, sizeof(found));
+		ntdb_foreach(set_found, found);
+		ok1(!found[0] && found[1] && !found[2]);
+
+		ntdb_close(ntdb1);
+		memset(found, 0, sizeof(found));
+		ntdb_foreach(set_found, found);
+		ok1(!found[0] && !found[1] && !found[2]);
+		ok1(tap_log_messages == 0);
+	}
+
+	return exit_status();
+}
diff --git a/lib/ntdb/test/run-traverse.c b/lib/ntdb/test/run-traverse.c
new file mode 100644
index 0000000000..9dfc94d3b3
--- /dev/null
+++ b/lib/ntdb/test/run-traverse.c
@@ -0,0 +1,203 @@
+#include "ntdb-source.h"
+#include "tap-interface.h"
+#include "logging.h"
+
+#define NUM_RECORDS 1000
+
+/* We use the same seed which we saw a failure on. */
+static uint64_t fixedhash(const void *key, size_t len, uint64_t seed, void *p)
+{
+	return hash64_stable((const unsigned char *)key, len,
+			     *(uint64_t *)p);
+}
+
+static bool store_records(struct ntdb_context *ntdb)
+{
+	int i;
+	NTDB_DATA key = { (unsigned char *)&i, sizeof(i) };
+	NTDB_DATA data = { (unsigned char *)&i, sizeof(i) };
+
+	for (i = 0; i < NUM_RECORDS; i++)
+		if (ntdb_store(ntdb, key, data, NTDB_REPLACE) != 0)
+			return false;
+	return true;
+}
+
+struct trav_data {
+	unsigned int calls, call_limit;
+	int low, high;
+	bool mismatch;
+	bool delete;
+	enum NTDB_ERROR delete_error;
+};
+
+static int trav(struct ntdb_context *ntdb, NTDB_DATA key, NTDB_DATA dbuf,
+		struct trav_data *td)
+{
+	int val;
+
+	td->calls++;
+	if (key.dsize != sizeof(val) || dbuf.dsize != sizeof(val)
+	    || memcmp(key.dptr, dbuf.dptr, key.dsize) != 0) {
+		td->mismatch = true;
+		return -1;
+	}
+	memcpy(&val, dbuf.dptr, dbuf.dsize);
+	if (val < td->low)
+		td->low = val;
+	if (val > td->high)
+		td->high = val;
+
+	if (td->delete) {
+		td->delete_error = ntdb_delete(ntdb, key);
+		if (td->delete_error != NTDB_SUCCESS) {
+			return -1;
+		}
+	}
+
+	if (td->calls == td->call_limit)
+		return 1;
+	return 0;
+}
+
+struct trav_grow_data {
+	unsigned int calls;
+	unsigned int num_large;
+	bool mismatch;
+	enum NTDB_ERROR error;
+};
+
+static int trav_grow(struct ntdb_context *ntdb, NTDB_DATA key, NTDB_DATA dbuf,
+		     struct trav_grow_data *tgd)
+{
+	int val;
+	unsigned char buffer[128] = { 0 };
+
+	tgd->calls++;
+	if (key.dsize != sizeof(val) || dbuf.dsize < sizeof(val)
+	    || memcmp(key.dptr, dbuf.dptr, key.dsize) != 0) {
+		tgd->mismatch = true;
+		return -1;
+	}
+
+	if (dbuf.dsize > sizeof(val))
+		/* We must have seen this before! */
+		tgd->num_large++;
+
+	/* Make a big difference to the database. */
+	dbuf.dptr = buffer;
+	dbuf.dsize = sizeof(buffer);
+	tgd->error = ntdb_append(ntdb, key, dbuf);
+	if (tgd->error != NTDB_SUCCESS) {
+		return -1;
+	}
+	return 0;
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	int num;
+	struct trav_data td;
+	struct trav_grow_data tgd;
+	struct ntdb_context *ntdb;
+	uint64_t seed = 16014841315512641303ULL;
+	int flags[] = { NTDB_INTERNAL, NTDB_DEFAULT, NTDB_NOMMAP,
+			NTDB_INTERNAL|NTDB_CONVERT, NTDB_CONVERT,
+			NTDB_NOMMAP|NTDB_CONVERT };
+	union ntdb_attribute hattr = { .hash = { .base = { NTDB_ATTRIBUTE_HASH },
+						.fn = fixedhash,
+						.data = &seed } };
+
+	hattr.base.next = &tap_log_attr;
+
+	plan_tests(sizeof(flags) / sizeof(flags[0]) * 32 + 1);
+	for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+		ntdb = ntdb_open("run-traverse.ntdb", flags[i],
+			       O_RDWR|O_CREAT|O_TRUNC, 0600, &hattr);
+		ok1(ntdb);
+		if (!ntdb)
+			continue;
+
+		ok1(ntdb_traverse(ntdb, NULL, NULL) == 0);
+
+		ok1(store_records(ntdb));
+		num = ntdb_traverse(ntdb, NULL, NULL);
+		ok1(num == NUM_RECORDS);
+
+		/* Full traverse. */
+		td.calls = 0;
+		td.call_limit = UINT_MAX;
+		td.low = INT_MAX;
+		td.high = INT_MIN;
+		td.mismatch = false;
+		td.delete = false;
+
+		num = ntdb_traverse(ntdb, trav, &td);
+		ok1(num == NUM_RECORDS);
+		ok1(!td.mismatch);
+		ok1(td.calls == NUM_RECORDS);
+		ok1(td.low == 0);
+		ok1(td.high == NUM_RECORDS-1);
+
+		/* Short traverse. */
+		td.calls = 0;
+		td.call_limit = NUM_RECORDS / 2;
+		td.low = INT_MAX;
+		td.high = INT_MIN;
+		td.mismatch = false;
+		td.delete = false;
+
+		num = ntdb_traverse(ntdb, trav, &td);
+		ok1(num == NUM_RECORDS / 2);
+		ok1(!td.mismatch);
+		ok1(td.calls == NUM_RECORDS / 2);
+		ok1(td.low <= NUM_RECORDS / 2);
+		ok1(td.high > NUM_RECORDS / 2);
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+		ok1(tap_log_messages == 0);
+
+		/* Deleting traverse (delete everything). */
+		td.calls = 0;
+		td.call_limit = UINT_MAX;
+		td.low = INT_MAX;
+		td.high = INT_MIN;
+		td.mismatch = false;
+		td.delete = true;
+		td.delete_error = NTDB_SUCCESS;
+		num = ntdb_traverse(ntdb, trav, &td);
+		ok1(num == NUM_RECORDS);
+		ok1(td.delete_error == NTDB_SUCCESS);
+		ok1(!td.mismatch);
+		ok1(td.calls == NUM_RECORDS);
+		ok1(td.low == 0);
+		ok1(td.high == NUM_RECORDS - 1);
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+		/* Now it's empty! */
+		ok1(ntdb_traverse(ntdb, NULL, NULL) == 0);
+
+		/* Re-add. */
+		ok1(store_records(ntdb));
+		ok1(ntdb_traverse(ntdb, NULL, NULL) == NUM_RECORDS);
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+
+		/* Grow.  This will cause us to be reshuffled. */
+		tgd.calls = 0;
+		tgd.num_large = 0;
+		tgd.mismatch = false;
+		tgd.error = NTDB_SUCCESS;
+		ok1(ntdb_traverse(ntdb, trav_grow, &tgd) > 1);
+		ok1(tgd.error == 0);
+		ok1(!tgd.mismatch);
+		ok1(ntdb_check(ntdb, NULL, NULL) == 0);
+		ok1(tgd.num_large < tgd.calls);
+		diag("growing db: %u calls, %u repeats",
+		     tgd.calls, tgd.num_large);
+
+		ntdb_close(ntdb);
+	}
+
+	ok1(tap_log_messages == 0);
+	return exit_status();
+}
diff --git a/lib/ntdb/test/tap-interface.c b/lib/ntdb/test/tap-interface.c
new file mode 100644
index 0000000000..077ec2cd9a
--- /dev/null
+++ b/lib/ntdb/test/tap-interface.c
@@ -0,0 +1,3 @@
+#include "tap-interface.h"
+
+unsigned tap_ok_count, tap_ok_target = -1U;
diff --git a/lib/ntdb/test/tap-interface.h b/lib/ntdb/test/tap-interface.h
new file mode 100644
index 0000000000..f3d4ec2545
--- /dev/null
+++ b/lib/ntdb/test/tap-interface.h
@@ -0,0 +1,41 @@
+/*
+   Unix SMB/CIFS implementation.
+   Simplistic implementation of tap interface.
+
+   Copyright (C) Rusty Russell 2012
+
+     ** NOTE! The following LGPL license applies to the talloc
+     ** library. This does NOT imply that all of Samba is released
+     ** under the LGPL
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with this library; if not, see <http://www.gnu.org/licenses/>.
+*/
+#include <stdio.h>
+#include <ccan/err/err.h>
+
+#ifndef __location__
+#define __TAP_STRING_LINE1__(s)    #s
+#define __TAP_STRING_LINE2__(s)   __TAP_STRING_LINE1__(s)
+#define __TAP_STRING_LINE3__  __TAP_STRING_LINE2__(__LINE__)
+#define __location__ __FILE__ ":" __TAP_STRING_LINE3__
+#endif
+
+extern unsigned tap_ok_count, tap_ok_target;
+#define plan_tests(num) do { tap_ok_target = (num); } while(0)
+#define ok(e, ...) ((e) ? (printf("."), tap_ok_count++, true) : (warnx(__VA_ARGS__), false))
+#define ok1(e) ok((e), "%s:%s", __location__, #e)
+#define pass(...) (printf("."), tap_ok_count++)
+#define fail(...) warnx(__VA_ARGS__)
+#define diag printf
+#define exit_status() (tap_ok_count == tap_ok_target ? 0 : 1)