MacOSDnsServerAddressStreamProvider.java — netty Source File

Source Code

/*
 * Copyright 2019 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.resolver.dns.macos;

import io.netty.resolver.dns.DnsServerAddressStream;
import io.netty.resolver.dns.DnsServerAddressStreamProvider;
import io.netty.resolver.dns.DnsServerAddressStreamProviders;
import io.netty.resolver.dns.DnsServerAddresses;
import io.netty.util.internal.ClassInitializerUtil;
import io.netty.util.internal.NativeLibraryLoader;
import io.netty.util.internal.PlatformDependent;
import io.netty.util.internal.StringUtil;
import io.netty.util.internal.ThrowableUtil;
import io.netty.util.internal.logging.InternalLogger;
import io.netty.util.internal.logging.InternalLoggerFactory;

import java.net.InetSocketAddress;
import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicLong;

/**
 * {@link DnsServerAddressStreamProvider} implementation which makes use of the same mechanism as
 * <a href="https://opensource.apple.com/tarballs/mDNSResponder/">Apple's open source mDNSResponder</a> to retrieve the
 * current nameserver configuration of the system.
 */
public final class MacOSDnsServerAddressStreamProvider implements DnsServerAddressStreamProvider {

    private static final Comparator<DnsResolver> RESOLVER_COMPARATOR =
            new Comparator<DnsResolver>() {
                @Override
                public int compare(DnsResolver r1, DnsResolver r2) {
                    // Note: order is descending (from higher to lower) so entries with lower search order override
                    // entries with higher search order.
                    return r1.searchOrder() < r2.searchOrder() ? 1 : r1.searchOrder() == r2.searchOrder() ? 0 : -1;
                }
            };

    private static final Throwable UNAVAILABILITY_CAUSE;

    private static final InternalLogger logger =
            InternalLoggerFactory.getInstance(MacOSDnsServerAddressStreamProvider.class);

// ... (143 more lines)