1 files changed, 53 insertions, 0 deletions
diff --git a/lib/libc/tests/db/dbm_nextkey_test.c b/lib/libc/tests/db/dbm_nextkey_test.c
new file mode 100644
index 000000000000..67b745efb196
--- /dev/null
+++ b/lib/libc/tests/db/dbm_nextkey_test.c
@@ -0,0 +1,53 @@
+/*-
+ * Copyright (c) 2025 Klara, Inc.
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <fcntl.h>
+#include <ndbm.h>
+#include <stdio.h>
+
+#include <atf-c.h>
+
+static const char *path = "tmp";
+static const char *dbname = "tmp.db";
+
+ATF_TC(dbm_nextkey_test);
+ATF_TC_HEAD(dbm_nextkey_test, tc)
+{
+	atf_tc_set_md_var(tc, "descr",
+	    "Check that dbm_nextkey always returns NULL after reaching the end of the database");
+}
+
+ATF_TC_BODY(dbm_nextkey_test, tc)
+{
+	DBM *db;
+	datum key, data;
+
+	data.dptr = "bar";
+	data.dsize = strlen("bar");
+	key.dptr = "foo";
+	key.dsize = strlen("foo");
+
+	db = dbm_open(path, O_RDWR | O_CREAT, 0755);
+	ATF_CHECK(db != NULL);
+	ATF_REQUIRE(atf_utils_file_exists(dbname));
+	ATF_REQUIRE(dbm_store(db, key, data, DBM_INSERT) != -1);
+
+	key = dbm_firstkey(db);
+	ATF_REQUIRE(key.dptr != NULL);
+	key = dbm_nextkey(db);
+	ATF_REQUIRE(key.dptr == NULL);
+	key = dbm_nextkey(db);
+	ATF_REQUIRE(key.dptr == NULL);
+
+	dbm_close(db);
+}
+
+ATF_TP_ADD_TCS(tp)
+{
+	ATF_TP_ADD_TC(tp, dbm_nextkey_test);
+
+	return (atf_no_error());
+}