| /* |
| * Copyright (C) 2019 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.android.net.module.util.netlink; |
| |
| import java.nio.ByteBuffer; |
| |
| /** |
| * struct nlmsgerr |
| * |
| * see <linux_src>/include/uapi/linux/netlink.h |
| * |
| * @hide |
| */ |
| public class StructNlMsgErr { |
| public static final int STRUCT_SIZE = Integer.BYTES + StructNlMsgHdr.STRUCT_SIZE; |
| |
| private static boolean hasAvailableSpace(ByteBuffer byteBuffer) { |
| return byteBuffer != null && byteBuffer.remaining() >= STRUCT_SIZE; |
| } |
| |
| /** |
| * Parse a netlink error message payload from a {@link ByteBuffer}. |
| * |
| * @param byteBuffer The buffer from which to parse the netlink error message payload. |
| * @return the parsed netlink error message payload, or {@code null} if the netlink error |
| * message payload could not be parsed successfully (for example, if it was truncated). |
| */ |
| public static StructNlMsgErr parse(ByteBuffer byteBuffer) { |
| if (!hasAvailableSpace(byteBuffer)) return null; |
| |
| // The ByteOrder must have already been set by the caller. In most |
| // cases ByteOrder.nativeOrder() is correct, with the exception |
| // of usage within unittests. |
| final StructNlMsgErr struct = new StructNlMsgErr(); |
| struct.error = byteBuffer.getInt(); |
| struct.msg = StructNlMsgHdr.parse(byteBuffer); |
| return struct; |
| } |
| |
| public int error; |
| public StructNlMsgHdr msg; |
| |
| /** |
| * Write the netlink error message payload to {@link ByteBuffer}. |
| */ |
| public void pack(ByteBuffer byteBuffer) { |
| // The ByteOrder must have already been set by the caller. In most |
| // cases ByteOrder.nativeOrder() is correct, with the possible |
| // exception of usage within unittests. |
| byteBuffer.putInt(error); |
| if (msg != null) { |
| msg.pack(byteBuffer); |
| } |
| } |
| |
| @Override |
| public String toString() { |
| return "StructNlMsgErr{ " |
| + "error{" + error + "}, " |
| + "msg{" + (msg == null ? "" : msg.toString()) + "} " |
| + "}"; |
| } |
| } |