Brian O'Connor | be95f68 | 2016-05-18 15:40:19 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2016-present Open Networking Laboratory |
| 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 org.onosproject.checkstyle; |
| 18 | |
| 19 | import com.puppycrawl.tools.checkstyle.api.CheckstyleException; |
| 20 | |
| 21 | import java.io.IOException; |
| 22 | import java.net.ServerSocket; |
| 23 | import java.nio.ByteBuffer; |
| 24 | import java.nio.channels.FileChannel; |
| 25 | import java.nio.channels.FileLock; |
| 26 | import java.nio.file.Files; |
| 27 | import java.nio.file.Path; |
| 28 | import java.nio.file.Paths; |
| 29 | import java.util.Timer; |
| 30 | import java.util.TimerTask; |
| 31 | import java.util.concurrent.ExecutorService; |
| 32 | import java.util.concurrent.Executors; |
| 33 | |
| 34 | import static java.nio.file.StandardOpenOption.*; |
| 35 | |
| 36 | /** |
| 37 | * Main program for executing scenario test warden. |
| 38 | */ |
| 39 | public final class Main { |
| 40 | |
| 41 | private static long POLLING_INTERVAL = 1000; //ms |
| 42 | |
| 43 | // Public construction forbidden |
| 44 | private Main(String[] args) { |
| 45 | } |
| 46 | |
| 47 | /** |
| 48 | * Main entry point for the cell warden. |
| 49 | * |
| 50 | * @param args command-line arguments |
| 51 | */ |
| 52 | public static void main(String[] args) |
| 53 | throws CheckstyleException, IOException { |
| 54 | startServer(args); |
| 55 | } |
| 56 | |
| 57 | // Monitors another PID and exit when that process exits |
| 58 | private static void watchProcess(String pid) { |
| 59 | if (pid == null || pid.equals("0")) { |
| 60 | return; |
| 61 | } |
| 62 | Timer timer = new Timer(true); // start as a daemon, so we don't hang shutdown |
| 63 | timer.scheduleAtFixedRate(new TimerTask() { |
| 64 | private String cmd = "kill -s 0 " + pid; |
| 65 | @Override |
| 66 | public void run() { |
| 67 | try { |
| 68 | Process p = Runtime.getRuntime().exec(cmd); |
| 69 | p.waitFor(); |
| 70 | if (p.exitValue() != 0) { |
| 71 | System.err.println("shutting down..."); |
| 72 | System.exit(0); |
| 73 | } |
| 74 | } catch (IOException | InterruptedException e) { |
| 75 | //no-op |
| 76 | e.printStackTrace(); |
| 77 | } |
| 78 | } |
| 79 | }, POLLING_INTERVAL, POLLING_INTERVAL); |
| 80 | } |
| 81 | |
| 82 | // Initiates a server. |
| 83 | private static void startServer(String[] args) throws IOException, CheckstyleException { |
| 84 | String portLock = args[0]; |
| 85 | String buckPid = args[1]; |
| 86 | String checkstyleFile = args[2]; |
| 87 | String suppressionsFile = args[3]; |
| 88 | |
| 89 | // Use a file lock to ensure only one copy of the daemon runs |
| 90 | Path portLockPath = Paths.get(portLock); |
| 91 | FileChannel channel = FileChannel.open(portLockPath, WRITE, CREATE); |
| 92 | FileLock lock = channel.tryLock(); |
| 93 | if (lock == null) { |
| 94 | System.out.println("Server is already running"); |
| 95 | System.exit(1); |
| 96 | } //else, hold the lock until the JVM exits |
| 97 | |
| 98 | // Start the server and bind it to a random port |
| 99 | ServerSocket server = new ServerSocket(0); |
| 100 | |
| 101 | // Monitor the parent buck process |
| 102 | watchProcess(buckPid); |
| 103 | |
| 104 | // Set up hook to clean up after ourselves |
| 105 | Runtime.getRuntime().addShutdownHook(new Thread(() -> { |
| 106 | try { |
| 107 | if (channel != null) { |
| 108 | channel.truncate(0); |
| 109 | channel.close(); |
| 110 | } |
| 111 | System.err.println("tear down..."); |
| 112 | Files.delete(portLockPath); |
| 113 | } catch (IOException e) { |
| 114 | //no-op: shutting down |
| 115 | e.printStackTrace(); |
| 116 | } |
| 117 | })); |
| 118 | |
| 119 | // Write the bound port to the port file |
| 120 | int port = server.getLocalPort(); |
| 121 | channel.truncate(0); |
| 122 | channel.write(ByteBuffer.wrap(Integer.toString(port).getBytes())); |
| 123 | |
| 124 | // Instantiate a Checkstyle runner and executor; serve until exit... |
| 125 | CheckstyleRunner runner = new CheckstyleRunner(checkstyleFile, suppressionsFile); |
| 126 | ExecutorService executor = Executors.newCachedThreadPool(); |
| 127 | while (true) { |
| 128 | try { |
| 129 | executor.submit(runner.checkClass(server.accept())); |
| 130 | } catch (Exception e) { |
| 131 | e.printStackTrace(); |
| 132 | //no-op |
| 133 | } |
| 134 | } |
| 135 | } |
| 136 | } |