1 files changed, 53 insertions, 0 deletions
diff --git a/lib/isc/mutex.c b/lib/isc/mutex.c
new file mode 100644
index 0000000..65f1663
--- /dev/null
+++ b/lib/isc/mutex.c
@@ -0,0 +1,53 @@
+/*
+ * 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 <errno.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <sys/time.h>
+#include <time.h>
+
+#include <isc/mutex.h>
+#include <isc/once.h>
+#include <isc/print.h>
+#include <isc/string.h>
+#include <isc/util.h>
+
+#ifdef HAVE_PTHREAD_MUTEX_ADAPTIVE_NP
+static bool attr_initialized = false;
+static pthread_mutexattr_t attr;
+static isc_once_t once_attr = ISC_ONCE_INIT;
+
+static void
+initialize_attr(void) {
+	RUNTIME_CHECK(pthread_mutexattr_init(&attr) == 0);
+	RUNTIME_CHECK(pthread_mutexattr_settype(
+			      &attr, PTHREAD_MUTEX_ADAPTIVE_NP) == 0);
+	attr_initialized = true;
+}
+#endif /* HAVE_PTHREAD_MUTEX_ADAPTIVE_NP */
+
+int
+isc__mutex_init(isc_mutex_t *mp) {
+#ifdef HAVE_PTHREAD_MUTEX_ADAPTIVE_NP
+	isc_result_t result = ISC_R_SUCCESS;
+	result = isc_once_do(&once_attr, initialize_attr);
+	RUNTIME_CHECK(result == ISC_R_SUCCESS);
+
+	return (pthread_mutex_init(mp, &attr));
+#else  /* HAVE_PTHREAD_MUTEX_ADAPTIVE_NP */
+	return (pthread_mutex_init(mp, NULL));
+#endif /* HAVE_PTHREAD_MUTEX_ADAPTIVE_NP */
+}