1 files changed, 29 insertions, 0 deletions
diff --git a/lib/isc/include/isc/once.h b/lib/isc/include/isc/once.h
new file mode 100644
index 0000000..7d341ca
--- /dev/null
+++ b/lib/isc/include/isc/once.h
@@ -0,0 +1,29 @@
+/*
+ * 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.
+ */
+
+#pragma once
+
+/*! \file */
+
+#include <pthread.h>
+
+#include <isc/result.h>
+
+typedef pthread_once_t isc_once_t;
+
+#define ISC_ONCE_INIT PTHREAD_ONCE_INIT
+
+/* XXX We could do fancier error handling... */
+
+#define isc_once_do(op, f) \
+	((pthread_once((op), (f)) == 0) ? ISC_R_SUCCESS : ISC_R_UNEXPECTED)