--- /dev/null	2020-01-06 11:04:45.000000000 +0000
+++ new/src/java.base/share/native/libnio/ch/nio_multicast.c	2020-01-06 11:04:45.000000000 +0000
@@ -0,0 +1,123 @@
+/*
+ * Copyright (c) 2020, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+#include <string.h>
+
+#include "nio_multicast.h"
+
+#define COPY_INET6_ADDRESS(env, source, target) \
+     (*env)->GetByteArrayRegion(env, source, 0, 16, target)
+
+/**
+ * Initialize a group_req structure with the given interface index and IPv4
+ * multicast group.
+ */
+void initGroupReq4(JNIEnv* env, struct group_req *req, jint index, jint group)
+{
+    struct sockaddr_in* sin;
+
+#ifdef WIN32
+    req->gr_interface = (ULONG)index;
+#else
+    req->gr_interface = (uint32_t)index;
+#endif
+
+    sin = (struct sockaddr_in*)&(req->gr_group);
+    memset(sin, 0, sizeof(struct sockaddr_in));
+    sin->sin_family = AF_INET;
+    sin->sin_addr.s_addr = htonl(group);
+}
+
+/**
+ * Initialize a group_source_req structure with the given interface index, IPv4
+ * multicast group, and IPv4 source address.
+ */
+void initGroupSourceReq4(JNIEnv* env, struct group_source_req *req,
+                         jint index, jint group, jint source)
+{
+    struct sockaddr_in* sin;
+
+#ifdef WIN32
+    req->gsr_interface = (ULONG)index;
+#else
+    req->gsr_interface = (uint32_t)index;
+#endif
+
+    sin = (struct sockaddr_in*)&(req->gsr_group);
+    memset(sin, 0, sizeof(struct sockaddr_in));
+    sin->sin_family = AF_INET;
+    sin->sin_addr.s_addr = htonl(group);
+
+    sin = (struct sockaddr_in*)&(req->gsr_source);
+    memset(sin, 0, sizeof(struct sockaddr_in));
+    sin->sin_family = AF_INET;
+    sin->sin_addr.s_addr = htonl(source);
+}
+
+/**
+ * Initialize a group_req structure with the given interface index and IPv6
+ * multicast group.
+ */
+void initGroupReq6(JNIEnv* env, struct group_req *req, jint index, jbyteArray group)
+{
+    struct sockaddr_in6* sin6;
+
+#ifdef WIN32
+    req->gr_interface = (ULONG)index;
+#else
+    req->gr_interface = (uint32_t)index;
+#endif
+
+    sin6 = (struct sockaddr_in6*)&(req->gr_group);
+    memset(sin6, 0, sizeof(struct sockaddr_in6));
+    sin6->sin6_family = AF_INET6;
+    COPY_INET6_ADDRESS(env, group, (jbyte*)&(sin6->sin6_addr));
+}
+
+/**
+ * Initialize a group_source req structure with the given interface index, IPv6
+ * multicast group, and IPv6 source address.
+ */
+void initGroupSourceReq6(JNIEnv* env, struct group_source_req *req,
+                         int index, jbyteArray group, jbyteArray source)
+{
+    struct sockaddr_in6* sin6;
+
+#ifdef WIN32
+    req->gsr_interface = (ULONG)index;
+#else
+    req->gsr_interface = (uint32_t)index;
+#endif
+
+    sin6 = (struct sockaddr_in6*)&(req->gsr_group);
+    memset(sin6, 0, sizeof(struct sockaddr_in6));
+    sin6->sin6_family = AF_INET6;
+    COPY_INET6_ADDRESS(env, group, (jbyte*)&(sin6->sin6_addr));
+
+    sin6 = (struct sockaddr_in6*)&(req->gsr_source);
+    memset(sin6, 0, sizeof(struct sockaddr_in6));
+    sin6->sin6_family = AF_INET6;
+    COPY_INET6_ADDRESS(env, source, (jbyte*)&(sin6->sin6_addr));
+}