NativeDatagramPacketArray.java — netty Source File

Source Code

/*
 * Copyright 2014 The Netty Project
 *
 * The Netty Project licenses this file to you 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:
 *
 *   https://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 io.netty.channel.epoll;

import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelOutboundBuffer;
import io.netty.channel.ChannelOutboundBuffer.MessageProcessor;
import io.netty.channel.socket.DatagramPacket;
import io.netty.channel.unix.IovArray;
import io.netty.channel.unix.Limits;
import io.netty.channel.unix.SegmentedDatagramPacket;
import io.netty.util.internal.UnstableApi;

import java.net.Inet6Address;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.UnknownHostException;

import static io.netty.channel.unix.Limits.UIO_MAX_IOV;
import static io.netty.channel.unix.NativeInetAddress.copyIpv4MappedIpv6Address;

/**
 * Support <a href="https://linux.die.net//man/2/sendmmsg">sendmmsg(...)</a> on linux with GLIBC 2.14+
 */
final class NativeDatagramPacketArray {

    // Use UIO_MAX_IOV as this is the maximum number we can write with one sendmmsg(...) call.
    private final NativeDatagramPacket[] packets = new NativeDatagramPacket[UIO_MAX_IOV];

    // We share one IovArray for all NativeDatagramPackets to reduce memory overhead. This will allow us to write
    // up to IOV_MAX iovec across all messages in one sendmmsg(...) call.
    private final IovArray iovArray = new IovArray();

    // temporary array to copy the ipv4 part of ipv6-mapped-ipv4 addresses and then create a Inet4Address out of it.
    private final byte[] ipv4Bytes = new byte[4];
    private final MyMessageProcessor processor = new MyMessageProcessor();

    private int count;

    NativeDatagramPacketArray() {
        for (int i = 0; i < packets.length; i++) {
            packets[i] = new NativeDatagramPacket();
        }
    }

    boolean addWritable(ByteBuf buf, int index, int len) {
        return add0(buf, index, len, 0, null);
// ... (173 more lines)