1 /* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package tests.net; 18 19 import java.io.IOException; 20 import java.net.InetAddress; 21 import java.net.InetSocketAddress; 22 import java.net.ServerSocket; 23 import java.net.Socket; 24 import java.net.UnknownHostException; 25 import java.util.ArrayList; 26 27 /** 28 * A test ServerSocket that you can't connect to --- connects will time out. 29 */ 30 public final class StuckServer { 31 private static final boolean DEBUG = false; 32 33 // RFC 5737 implies this network -- "test net 1" -- will be unreachable. 34 // (There are two other networks to try if we have trouble with this one.) 35 // We've had trouble with 10.* in the past (because test labs running CTS often use 36 // net 10!) but hopefully this network will be better. 37 public static final InetAddress UNREACHABLE_ADDRESS; 38 static { 39 try { 40 UNREACHABLE_ADDRESS = InetAddress.getByAddress(new byte[] { (byte) 192, 0, 2, 0 }); 41 } catch (UnknownHostException ex) { 42 throw new AssertionError(ex); 43 } 44 } 45 46 private ServerSocket serverSocket; 47 private InetSocketAddress address; 48 private ArrayList<Socket> clients = new ArrayList<Socket>(); 49 50 public StuckServer(boolean useBacklog) throws IOException { 51 // Set a backlog and use it up so that we can expect the 52 // connection to time out. According to Stevens 53 // 4.5 "listen function", Linux adds 3 to the specified 54 // backlog, so we need to connect 4 times before it will hang. 55 // The trouble with this is that it won't hang forever. 56 // After 10s or so, the kernel allows a couple more connections. 57 // This mode is ony useful if you actually want to continue eventually; we use it to 58 // test non-blocking connects, for example, where you want to test every part of the code. 59 if (useBacklog) { 60 this.serverSocket = new ServerSocket(0, 1); 61 this.address = (InetSocketAddress) serverSocket.getLocalSocketAddress(); 62 if (DEBUG) { 63 System.err.println("StuckServer: " + serverSocket); 64 } 65 for (int i = 0; i < 4; ++i) { 66 Socket client = new Socket(serverSocket.getInetAddress(), serverSocket.getLocalPort()); 67 clients.add(client); 68 if (DEBUG) { 69 System.err.println("StuckServer client " + i + " - " + client); 70 } 71 } 72 } else { 73 // In general, though, you don't want to rely on listen(2) backlog. http://b/6971145. 74 this.address = new InetSocketAddress(UNREACHABLE_ADDRESS, 80); 75 } 76 } 77 78 public InetSocketAddress getLocalSocketAddress() { 79 return address; 80 } 81 82 public int getLocalPort() { 83 return address.getPort(); 84 } 85 86 public void close() throws IOException { 87 if (serverSocket != null) { 88 serverSocket.close(); 89 } 90 for (Socket client : clients) { 91 client.close(); 92 } 93 } 94 } 95
