/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.tomcat.util.net;
import java.io.IOException;
import java.net.BindException;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.SocketException;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.Iterator;
import java.util.concurrent.ConcurrentLinkedQueue;
import java.util.concurrent.RejectedExecutionException;
import org.apache.juli.logging.Log;
import org.apache.juli.logging.LogFactory;
import org.apache.tomcat.util.ExceptionUtils;
import org.apache.tomcat.util.net.AbstractEndpoint.Handler.SocketState;
import org.apache.tomcat.util.security.PrivilegedSetTccl;
/**
* Handle incoming TCP connections.
*
* This class implement a simple server model: one listener thread accepts on a socket and
* creates a new worker thread for each incoming connection.
*
* More advanced Endpoints will reuse the threads, use queues, etc.
*
* @author James Duncan Davidson
* @author Jason Hunter
* @author James Todd
* @author Costin Manolache
* @author Gal Shachor
* @author Yoav Shapira
* @author Remy Maucherat
*/
public class JIoEndpoint extends AbstractEndpoint<Socket> {
// -------------------------------------------------------------- Constants
private static final Log log = LogFactory.getLog(JIoEndpoint.class);
// ----------------------------------------------------------------- Fields
/**
* Associated server socket.
*/
protected ServerSocket serverSocket = null;
// ------------------------------------------------------------ Constructor
public JIoEndpoint() {
// Set maxConnections to zero so we can tell if the user has specified
// their own value on the connector when we reach bind()
setMaxConnections(0);
// Reduce the executor timeout for BIO as threads in keep-alive will not
// terminate when the executor interrupts them.
setExecutorTerminationTimeoutMillis(0);
}
// ------------------------------------------------------------- Properties
/**
* Handling of accepted sockets.
*/
protected Handler handler = null;
public void setHandler(Handler handler ) { this.handler = handler; }
public Handler getHandler() { return handler; }
/**
* Server socket factory.
*/
protected ServerSocketFactory serverSocketFactory = null;
public void setServerSocketFactory(ServerSocketFactory factory) { this.serverSocketFactory = factory; }
public ServerSocketFactory getServerSocketFactory() { return serverSocketFactory; }
/**
* Port in use.
*/
@Override
public int getLocalPort() {
ServerSocket s = serverSocket;
if (s == null) {
return -1;
} else {
return s.getLocalPort();
}
}
/*
* Optional feature support.
*/
@Override
public boolean getUseSendfile() { return false; } // Not supported
@Override
public boolean getUseComet() { return false; } // Not supported
@Override
public boolean getUseCometTimeout() { return false; } // Not supported
@Override
public boolean getDeferAccept() { return false; } // Not supported
@Override
public boolean getUsePolling() { return false; } // Not supported
// ------------------------------------------------ Handler Inner Interface
/**
* Bare bones interface used for socket processing. Per thread data is to be
* stored in the ThreadWithAttributes extra folders, or alternately in
* thread local fields.
*/
public interface Handler extends AbstractEndpoint.Handler {
public SocketState process(SocketWrapper<Socket> socket,
SocketStatus status);
public SSLImplementation getSslImplementation();
}
/**
* Async timeout thread
*/
protected class AsyncTimeout implements Runnable {
/**
* The background thread that checks async requests and fires the
* timeout if there has been no activity.
*/
@Override
public void run() {
// Loop until we receive a shutdown command
while (running) {
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
// Ignore
}
long now = System.currentTimeMillis();
Iterator<SocketWrapper<Socket>> sockets =
waitingRequests.iterator();
while (sockets.hasNext()) {
SocketWrapper<Socket> socket = sockets.next();
long access = socket.getLastAccess();
if (socket.getTimeout() > 0 &&
(now-access)>socket.getTimeout()) {
// Prevent multiple timeouts
socket.setTimeout(-1);
processSocketAsync(socket,SocketStatus.TIMEOUT);
}
}
// Loop if endpoint is paused
while (paused && running) {
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
// Ignore
}
}
}
}
}
// --------------------------------------------------- Acceptor Inner Class
/**
* The background thread that listens for incoming TCP/IP connections and
* hands them off to an appropriate processor.
*/
protected class Acceptor extends AbstractEndpoint.Acceptor {
@Override
public void run() {
int errorDelay = 0;
// Loop until we receive a shutdown command
while (running) {
// Loop if endpoint is paused
while (paused && running) {
state = AcceptorState.PAUSED;
try {
Thread.sleep(50);
} catch (InterruptedException e) {
// Ignore
}
}
if (!running) {
break;
}
state = AcceptorState.RUNNING;
try {
//if we have reached max connections, wait
countUpOrAwaitConnection();
Socket socket = null;
try {
// Accept the next incoming connection from the server
// socket
socket = serverSocketFactory.acceptSocket(serverSocket);
} catch (IOException ioe) {
countDownConnection();
// Introduce delay if necessary
errorDelay = handleExceptionWithDelay(errorDelay);
// re-throw
throw ioe;
}
// Successful accept, reset the error delay
errorDelay = 0;
// Configure the socket
if (running && !paused && setSocketOptions(socket)) {
// Hand this socket off to an appropriate processor
if (!processSocket(socket)) {
countDownConnection();
// Close socket right away
closeSocket(socket);
}
} else {
countDownConnection();
// Close socket right away
closeSocket(socket);
}
} catch (IOException x) {
if (running) {
log.error(sm.getString("endpoint.accept.fail"), x);
}
} catch (NullPointerException npe) {
if (running) {
log.error(sm.getString("endpoint.accept.fail"), npe);
}
} catch (Throwable t) {
ExceptionUtils.handleThrowable(t);
log.error(sm.getString("endpoint.accept.fail"), t);
}
}
state = AcceptorState.ENDED;
}
}
private void closeSocket(Socket socket) {
try {
socket.close();
} catch (IOException e) {
// Ignore
}
}
// ------------------------------------------- SocketProcessor Inner Class
/**
* This class is the equivalent of the Worker, but will simply use in an
* external Executor thread pool.
*/
protected class SocketProcessor implements Runnable {
protected SocketWrapper<Socket> socket = null;
protected SocketStatus status = null;
public SocketProcessor(SocketWrapper<Socket> socket) {
if (socket==null) throw new NullPointerException();
this.socket = socket;
}
public SocketProcessor(SocketWrapper<Socket> socket, SocketStatus status) {
this(socket);
this.status = status;
}
@Override
public void run() {
boolean launch = false;
synchronized (socket) {
try {
SocketState state = SocketState.OPEN;
try {
// SSL handshake
serverSocketFactory.handshake(socket.getSocket());
} catch (Throwable t) {
ExceptionUtils.handleThrowable(t);
if (log.isDebugEnabled()) {
log.debug(sm.getString("endpoint.err.handshake"), t);
}
// Tell to close the socket
state = SocketState.CLOSED;
}
if ((state != SocketState.CLOSED)) {
if (status == null) {
state = handler.process(socket, SocketStatus.OPEN_READ);
} else {
state = handler.process(socket,status);
}
}
if (state == SocketState.CLOSED) {
// Close socket
if (log.isTraceEnabled()) {
log.trace("Closing socket:"+socket);
}
countDownConnection();
try {
socket.getSocket().close();
} catch (IOException e) {
// Ignore
}
} else if (state == SocketState.OPEN ||
state == SocketState.UPGRADING ||
state == SocketState.UPGRADING_TOMCAT ||
state == SocketState.UPGRADED){
socket.setKeptAlive(true);
socket.access();
launch = true;
} else if (state == SocketState.LONG) {
socket.access();
waitingRequests.add(socket);
}
} finally {
if (launch) {
try {
getExecutor().execute(new SocketProcessor(socket, SocketStatus.OPEN_READ));
} catch (RejectedExecutionException x) {
log.warn("Socket reprocessing request was rejected for:"+socket,x);
try {
//unable to handle connection at this time
handler.process(socket, SocketStatus.DISCONNECT);
} finally {
countDownConnection();
}
} catch (NullPointerException npe) {
if (running) {
log.error(sm.getString("endpoint.launch.fail"),
npe);
}
}
}
}
}
socket = null;
// Finish up this request
}
}
// -------------------- Public methods --------------------
@Override
public void bind() throws Exception {
// Initialize thread count defaults for acceptor
if (acceptorThreadCount == 0) {
acceptorThreadCount = 1;
}
// Initialize maxConnections
if (getMaxConnections() == 0) {
// User hasn't set a value - use the default
setMaxConnections(getMaxThreadsInternal());
}
if (serverSocketFactory == null) {
if (isSSLEnabled()) {
serverSocketFactory =
handler.getSslImplementation().getServerSocketFactory(this);
} else {
serverSocketFactory = new DefaultServerSocketFactory(this);
}
}
if (serverSocket == null) {
try {
if (getAddress() == null) {
serverSocket = serverSocketFactory.createSocket(getPort(),
getBacklog());
} else {
serverSocket = serverSocketFactory.createSocket(getPort(),
getBacklog(), getAddress());
}
} catch (BindException orig) {
String msg;
if (getAddress() == null)
msg = orig.getMessage() + " <null>:" + getPort();
else
msg = orig.getMessage() + " " +
getAddress().toString() + ":" + getPort();
BindException be = new BindException(msg);
be.initCause(orig);
throw be;
}
}
}
@Override
public void startInternal() throws Exception {
if (!running) {
running = true;
paused = false;
// Create worker collection
if (getExecutor() == null) {
createExecutor();
}
initializeConnectionLatch();
startAcceptorThreads();
// Start async timeout thread
Thread timeoutThread = new Thread(new AsyncTimeout(),
getName() + "-AsyncTimeout");
timeoutThread.setPriority(threadPriority);
timeoutThread.setDaemon(true);
timeoutThread.start();
}
}
@Override
public void stopInternal() {
releaseConnectionLatch();
if (!paused) {
pause();
}
if (running) {
running = false;
unlockAccept();
}
shutdownExecutor();
}
/**
* Deallocate APR memory pools, and close server socket.
*/
@Override
public void unbind() throws Exception {
if (running) {
stop();
}
if (serverSocket != null) {
try {
if (serverSocket != null)
serverSocket.close();
} catch (Exception e) {
log.error(sm.getString("endpoint.err.close"), e);
}
serverSocket = null;
}
handler.recycle();
}
@Override
protected AbstractEndpoint.Acceptor createAcceptor() {
return new Acceptor();
}
/**
* Configure the socket.
*/
protected boolean setSocketOptions(Socket socket) {
try {
// 1: Set socket options: timeout, linger, etc
socketProperties.setProperties(socket);
} catch (SocketException s) {
//error here is common if the client has reset the connection
if (log.isDebugEnabled()) {
log.debug(sm.getString("endpoint.err.unexpected"), s);
}
// Close the socket
return false;
} catch (Throwable t) {
ExceptionUtils.handleThrowable(t);
log.error(sm.getString("endpoint.err.unexpected"), t);
// Close the socket
return false;
}
return true;
}
/**
* Process a new connection from a new client. Wraps the socket so
* keep-alive and other attributes can be tracked and then passes the socket
* to the executor for processing.
*
* @param socket The socket associated with the client.
*
* @return <code>true</code> if the socket is passed to the
* executor, <code>false</code> if something went wrong or
* if the endpoint is shutting down. Returning
* <code>false</code> is an indication to close the socket
* immediately.
*/
protected boolean processSocket(Socket socket) {
// Process the request from this socket
try {
SocketWrapper<Socket> wrapper = new SocketWrapper<Socket>(socket);
wrapper.setKeepAliveLeft(getMaxKeepAliveRequests());
wrapper.setSecure(isSSLEnabled());
// During shutdown, executor may be null - avoid NPE
if (!running) {
return false;
}
getExecutor().execute(new SocketProcessor(wrapper));
} catch (RejectedExecutionException x) {
log.warn("Socket processing request was rejected for:"+socket,x);
return false;
} catch (Throwable t) {
ExceptionUtils.handleThrowable(t);
// This means we got an OOM or similar creating a thread, or that
// the pool and its queue are full
log.error(sm.getString("endpoint.process.fail"), t);
return false;
}
return true;
}
/**
* Process an existing async connection. If processing is required, passes
* the wrapped socket to an executor for processing.
*
* @param socket The socket associated with the client.
* @param status Only OPEN and TIMEOUT are used. The others are used for
* Comet requests that are not supported by the BIO (JIO)
* Connector.
*/
@Override
public void processSocketAsync(SocketWrapper<Socket> socket,
SocketStatus status) {
try {
synchronized (socket) {
if (waitingRequests.remove(socket)) {
SocketProcessor proc = new SocketProcessor(socket,status);
ClassLoader loader = Thread.currentThread().getContextClassLoader();
try {
//threads should not be created by the webapp classloader
if (Constants.IS_SECURITY_ENABLED) {
PrivilegedAction<Void> pa = new PrivilegedSetTccl(
getClass().getClassLoader());
AccessController.doPrivileged(pa);
} else {
Thread.currentThread().setContextClassLoader(
getClass().getClassLoader());
}
// During shutdown, executor may be null - avoid NPE
if (!running) {
return;
}
getExecutor().execute(proc);
//TODO gotta catch RejectedExecutionException and properly handle it
} finally {
if (Constants.IS_SECURITY_ENABLED) {
PrivilegedAction<Void> pa = new PrivilegedSetTccl(loader);
AccessController.doPrivileged(pa);
} else {
Thread.currentThread().setContextClassLoader(loader);
}
}
}
}
} catch (Throwable t) {
ExceptionUtils.handleThrowable(t);
// This means we got an OOM or similar creating a thread, or that
// the pool and its queue are full
log.error(sm.getString("endpoint.process.fail"), t);
}
}
protected ConcurrentLinkedQueue<SocketWrapper<Socket>> waitingRequests =
new ConcurrentLinkedQueue<SocketWrapper<Socket>>();
@Override
public void removeWaitingRequest(SocketWrapper<Socket> socketWrapper) {
waitingRequests.remove(socketWrapper);
}
@Override
protected Log getLog() {
return log;
}
}