--- /dev/null
+#include <ccan/tdb2/tdb.c>
+#include <ccan/tdb2/free.c>
+#include <ccan/tdb2/lock.c>
+#include <ccan/tdb2/io.c>
+#include <ccan/tdb2/check.c>
+#include <ccan/tap/tap.h>
+#include "logging.h"
+
+int main(int argc, char *argv[])
+{
+ unsigned int i;
+ uint64_t val;
+ struct tdb_context *tdb;
+ int flags[] = { TDB_INTERNAL, TDB_DEFAULT, TDB_NOMMAP,
+ TDB_INTERNAL|TDB_CONVERT, TDB_CONVERT,
+ TDB_NOMMAP|TDB_CONVERT };
+
+ plan_tests(sizeof(flags) / sizeof(flags[0]) * 18 + 1);
+
+ for (i = 0; i < sizeof(flags) / sizeof(flags[0]); i++) {
+ tdb = tdb_open("run-expand.tdb", flags[i],
+ O_RDWR|O_CREAT|O_TRUNC, 0600, &tap_log_attr);
+ ok1(tdb);
+ if (!tdb)
+ continue;
+
+ /* First expand. Should add a zone, doubling file size.. */
+ val = tdb->map_size - 1 - sizeof(struct tdb_header);
+ ok1(tdb_expand(tdb, 1, 1, false) == 0);
+ ok1(tdb->map_size == 2 * val + 1 + sizeof(struct tdb_header));
+ ok1(tdb_check(tdb, NULL, NULL) == 0);
+
+ /* Second expand, add another zone of same size. */
+ ok1(tdb_expand(tdb, 1, 1, false) == 0);
+ ok1(tdb->map_size == 3 * val + 1 + sizeof(struct tdb_header));
+ ok1(tdb_check(tdb, NULL, NULL) == 0);
+
+ /* Large expand, but can only add 4th zone of same size. */
+ ok1(tdb_expand(tdb, 0, 4*val, false) == 0);
+ ok1(tdb->map_size == 4 * val + 1 + sizeof(struct tdb_header));
+ ok1(tdb_check(tdb, NULL, NULL) == 0);
+
+ /* Large expand now will double file. */
+ ok1(tdb_expand(tdb, 0, 4*val, false) == 0);
+ ok1(tdb->map_size == 8 * val + 1 + sizeof(struct tdb_header));
+ ok1(tdb_check(tdb, NULL, NULL) == 0);
+
+ /* And again? */
+ ok1(tdb_expand(tdb, 0, 4*val, false) == 0);
+ ok1(tdb->map_size == 16 * val + 1 + sizeof(struct tdb_header));
+ ok1(tdb_check(tdb, NULL, NULL) == 0);
+
+ /* Below comfort level, will add a single 8*val zone. */
+ ok1(tdb_expand(tdb, 0, ((8*val) >> TDB_COMFORT_FACTOR_BITS)
+ - sizeof(struct tdb_used_record), false) == 0);
+ ok1(tdb->map_size == 24 * val + 1 + sizeof(struct tdb_header));
+ tdb_close(tdb);
+ }
+
+ ok1(tap_log_messages == 0);
+ return exit_status();
+}