1 files changed, 54 insertions, 0 deletions
diff --git a/lib/dns/timer.c b/lib/dns/timer.c
new file mode 100644
index 0000000..ef2895d
--- /dev/null
+++ b/lib/dns/timer.c
@@ -0,0 +1,54 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, you can obtain one at https://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+/*! \file */
+
+#include <stdbool.h>
+
+#include <isc/result.h>
+#include <isc/time.h>
+#include <isc/timer.h>
+
+#include <dns/timer.h>
+#include <dns/types.h>
+
+#define CHECK(op)                            \
+	do {                                 \
+		result = (op);               \
+		if (result != ISC_R_SUCCESS) \
+			goto failure;        \
+	} while (0)
+
+isc_result_t
+dns_timer_setidle(isc_timer_t *timer, unsigned int maxtime,
+		  unsigned int idletime, bool purge) {
+	isc_result_t result;
+	isc_interval_t maxinterval, idleinterval;
+	isc_time_t expires;
+
+	/* Compute the time of expiry. */
+	isc_interval_set(&maxinterval, maxtime, 0);
+	CHECK(isc_time_nowplusinterval(&expires, &maxinterval));
+
+	/*
+	 * Compute the idle interval, and add a spare nanosecond to
+	 * work around the silly limitation of the ISC timer interface
+	 * that you cannot specify an idle interval of zero.
+	 */
+	isc_interval_set(&idleinterval, idletime, 1);
+
+	CHECK(isc_timer_reset(timer, isc_timertype_once, &expires,
+			      &idleinterval, purge));
+failure:
+	return (result);
+}