/**
* Copyright 2011 JogAmp Community. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification, are
* permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this list of
* conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice, this list
* of conditions and the following disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY JogAmp Community ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JogAmp Community OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* The views and conclusions contained in the software and documentation are those of the
* authors and should not be interpreted as representing official policies, either expressed
* or implied, of JogAmp Community.
*/
package jogamp.common.util.locks;
import java.io.IOException;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.UnknownHostException;
import com.jogamp.common.ExceptionUtils;
import com.jogamp.common.util.InterruptSource;
import com.jogamp.common.util.InterruptedRuntimeException;
import com.jogamp.common.util.SourcedInterruptedException;
import com.jogamp.common.util.locks.SingletonInstance;
public class SingletonInstanceServerSocket extends SingletonInstance {
private static int serverInstanceCount = 0;
private final Server singletonServer;
private final String fullName;
public SingletonInstanceServerSocket(final long poll_ms, final int portNumber) {
super(poll_ms);
// Gather the local InetAddress, loopback is prioritized
InetAddress ilh = null;
try {
ilh = InetAddress.getByName(null); // loopback
} catch (final UnknownHostException e1) { }
if(null == ilh) {
try {
ilh = InetAddress.getByName("localhost");
if(null!=ilh && !ilh.isLoopbackAddress()) { ilh = null; }
} catch (final UnknownHostException e1) { }
}
if(null == ilh) {
try {
ilh = InetAddress.getByAddress(new byte[] { 127, 0, 0, 1 } );
if(null!=ilh && !ilh.isLoopbackAddress()) { ilh = null; }
} catch (final UnknownHostException e) { }
}
if(null == ilh) {
try {
ilh = InetAddress.getLocalHost();
} catch (final UnknownHostException e) { }
}
if(null == ilh) {
throw new RuntimeException(infoPrefix()+" EEE Could not determine local InetAddress");
}
fullName = ilh.toString()+":"+portNumber;
singletonServer = new Server(ilh, portNumber);
Runtime.getRuntime().addShutdownHook(new InterruptSource.Thread() {
@Override
public void run() {
singletonServer.kill();
}
});
}
public final InetAddress getLocalInetAddress() {
return singletonServer.getLocalInetAddress();
}
public final int getPortNumber() {
return singletonServer.getPortNumber();
}
@Override
public final String getName() { return fullName; }
@Override
protected boolean tryLockImpl() {
if( singletonServer.isRunning() ) {
return false; // same JVM .. server socket already installed !
}
// check if other JVM's locked the server socket ..
final Socket clientSocket = singletonServer.connect();
if(null != clientSocket) {
try {
clientSocket.close();
} catch (final IOException e) { }
return false;
}
if( !singletonServer.start() ) {
return false;
}
return true;
}
@Override
protected boolean unlockImpl() {
return singletonServer.shutdown();
}
public class Server implements Runnable {
private final InetAddress localInetAddress;
private final int portNumber;
private volatile boolean shallQuit = false;
private volatile boolean alive = false;
private final Object syncOnStartStop = new Object();
private ServerSocket serverSocket = null;
private Thread serverThread = null; // allowing kill() to force-stop last server-thread
public Server(final InetAddress localInetAddress, final int portNumber) {
this.localInetAddress = localInetAddress;
this.portNumber = portNumber;
}
public final InetAddress getLocalInetAddress() { return localInetAddress; }
public final int getPortNumber() { return portNumber; }
public final boolean start() {
if(alive) return true;
final String sname;
synchronized (Server.class) {
serverInstanceCount++;
sname = "SingletonServerSocket"+serverInstanceCount+"-"+fullName;
}
synchronized (syncOnStartStop) {
shallQuit = false;
serverThread = new InterruptSource.Thread(null, this, sname);
serverThread.setDaemon(true); // be a daemon, don't keep the JVM running
serverThread.start();
try {
while( !alive && !shallQuit ) {
syncOnStartStop.wait();
}
} catch (final InterruptedException ie) {
final InterruptedException ie2 = SourcedInterruptedException.wrap(ie);
shutdown(false);
throw new InterruptedRuntimeException(ie2);
}
}
final boolean ok = isBound();
if(!ok) {
shutdown(true);
}
return ok;
}
public final boolean shutdown() {
return shutdown(true);
}
private final boolean shutdown(final boolean wait) {
if(!alive) return true;
try {
synchronized (syncOnStartStop) {
shallQuit = true;
connect();
if( wait ) {
try {
while( alive ) {
syncOnStartStop.wait();
}
} catch (final InterruptedException ie) {
throw new InterruptedRuntimeException(ie);
}
}
}
} finally {
if(alive) {
System.err.println(infoPrefix()+" EEE "+getName()+" - Unable to remove lock: ServerThread still alive ?");
kill();
}
}
return true;
}
/**
* Brutally kill server thread and close socket regardless.
* This is out last chance for JVM shutdown.
*/
@SuppressWarnings("deprecation")
public final void kill() {
if(alive) {
System.err.println(infoPrefix()+" XXX "+getName()+" - Kill @ JVM Shutdown");
}
alive = false;
shallQuit = false;
if(null != serverThread && serverThread.isAlive() ) {
try {
serverThread.stop();
} catch(final Throwable t) { }
}
if(null != serverSocket) {
try {
final ServerSocket ss = serverSocket;
serverSocket = null;
ss.close();
} catch (final Throwable t) { }
}
}
public final boolean isRunning() { return alive; }
public final boolean isBound() {
return alive && null != serverSocket && serverSocket.isBound() ;
}
public final Socket connect() {
try {
return new Socket(localInetAddress, portNumber);
} catch (final Exception e) { }
return null;
}
@Override
public void run() {
if(DEBUG) {
System.err.println(infoPrefix()+" III - Start");
}
try {
synchronized (syncOnStartStop) {
try {
serverSocket = new ServerSocket(portNumber, 1, localInetAddress);
serverSocket.setReuseAddress(true); // reuse same port w/ subsequent instance, i.e. overcome TO state when JVM crashed
alive = true;
} catch (final IOException e) {
System.err.println(infoPrefix()+" III - Unable to install ServerSocket: "+e.getMessage());
shallQuit = true;
} finally {
syncOnStartStop.notifyAll();
}
}
while (!shallQuit) {
try {
final Socket clientSocket = serverSocket.accept();
clientSocket.close();
} catch (final IOException ioe) {
System.err.println(infoPrefix()+" EEE - Exception during accept: " + ioe.getMessage());
}
}
} catch(final ThreadDeath td) {
if( DEBUG ) {
ExceptionUtils.dumpThrowable("", td);
}
} finally {
synchronized (syncOnStartStop) {
if(DEBUG) {
System.err.println(infoPrefix()+" III - Stopping: alive "+alive+", shallQuit "+shallQuit+", hasSocket "+(null!=serverSocket));
}
if(null != serverSocket) {
try {
serverSocket.close();
} catch (final IOException e) {
System.err.println(infoPrefix()+" EEE - Exception during close: " + e.getMessage());
}
}
serverSocket = null;
alive = false;
syncOnStartStop.notifyAll();
}
}
}
}
}