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.util.ArrayList; 25 26 /** 27 * A test ServerSocket that you can't connect to --- connects will time out. 28 */ 29 public final class StuckServer { 30 private static final boolean DEBUG = false; 31 32 private ServerSocket serverSocket; 33 private InetSocketAddress address; 34 private ArrayList<Socket> clients = new ArrayList<Socket>(); 35 36 public StuckServer(boolean useBacklog) throws IOException { 37 // Set a backlog and use it up so that we can expect the 38 // connection to time out. According to Stevens 39 // 4.5 "listen function", Linux adds 3 to the specified 40 // backlog, so we need to connect 4 times before it will hang. 41 // The trouble with this is that it won't hang forever. 42 // After 10s or so, the kernel allows a couple more connections. 43 // This mode is ony useful if you actually want to continue eventually; we use it to 44 // test non-blocking connects, for example, where you want to test every part of the code. 45 if (useBacklog) { 46 this.serverSocket = new ServerSocket(0, 1); 47 this.address = (InetSocketAddress) serverSocket.getLocalSocketAddress(); 48 if (DEBUG) { 49 System.err.println("StuckServer: " + serverSocket); 50 } 51 for (int i = 0; i < 4; ++i) { 52 Socket client = new Socket(serverSocket.getInetAddress(), serverSocket.getLocalPort()); 53 clients.add(client); 54 if (DEBUG) { 55 System.err.println("StuckServer client " + i + " - " + client); 56 } 57 } 58 } else { 59 // In general, though, you don't want to rely on listen(2) backlog. http://b/6971145. 60 // RFC 5737 implies this network will be unreachable. (There are two other networks 61 // to try if we have trouble with this one.) 62 // We've had trouble with 10.* in the past (because test labs running CTS often use 63 // net 10!) but hopefully this network will be better. 64 InetAddress testNet1 = InetAddress.getByAddress(new byte[] { (byte) 192, 0, 2, 0 }); 65 this.address = new InetSocketAddress(testNet1, 80); 66 } 67 } 68 69 public InetSocketAddress getLocalSocketAddress() { 70 return address; 71 } 72 73 public int getLocalPort() { 74 return address.getPort(); 75 } 76 77 public void close() throws IOException { 78 if (serverSocket != null) { 79 serverSocket.close(); 80 } 81 for (Socket client : clients) { 82 client.close(); 83 } 84 } 85 } 86