/*
*
* Panbox - encryption for cloud storage
* Copyright (C) 2014-2015 by Fraunhofer SIT and Sirrix AG
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* Additonally, third party code may be provided with notices and open source
* licenses from communities and third parties that govern the use of those
* portions, and any licenses granted hereunder do not alter any rights and
* obligations you may have under such open source licenses, however, the
* disclaimer of warranty and limitation of liability provisions of the GPLv3
* will apply to all the product.
*
*/
package org.panbox.desktop.common.utils;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class SingleInstanceLockWMIC {
private static final String PANBOX_CLIENT_CLASS = "org.panbox.desktop.windows.client.PanboxClient";
private static boolean locked = false;
private SingleInstanceLockWMIC() {
}
/**
* Creates the lock file if it's not present and requests its deletion on
* program termination or informs that the program is already running if
* that's the case.
*
* @return true - if the operation was successful or if the program already
* has the lock.<br>
* false - if the program is already running
* @throws IOException
* if the lock file cannot be created.
*/
public static boolean lock() throws IOException {
if (locked)
return true;
if (processExists())
return false;
locked = true;
return true;
}
private static boolean processExists() {
try {
boolean foundOnce = false;
ProcessBuilder pb = new ProcessBuilder("wmic", "process", "list");
pb.redirectErrorStream(true);
Process p = pb.start();
p.getOutputStream().close();
BufferedReader br = new BufferedReader(new InputStreamReader(p.getInputStream()));
String tmp = null;
while ((tmp = br.readLine()) != null) {
if(tmp.contains(PANBOX_CLIENT_CLASS)) {
if(!foundOnce) {
foundOnce = true;
} else {
// foundTwice
return true;
}
}
}
p.waitFor();
} catch (IOException | InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return false;
}
public static void forceUnlock() {
// not needed anymore!
locked = false;
}
}