SocketWrapperBase.java
/*
* 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.EOFException;
import java.io.IOException;
import java.net.SocketTimeoutException;
import java.nio.ByteBuffer;
import java.nio.channels.CompletionHandler;
import java.nio.channels.InterruptedByTimeoutException;
import java.nio.channels.ReadPendingException;
import java.nio.channels.WritePendingException;
import java.util.concurrent.Executor;
import java.util.concurrent.RejectedExecutionException;
import java.util.concurrent.Semaphore;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicLong;
import java.util.concurrent.atomic.AtomicReference;
import java.util.concurrent.locks.ReentrantLock;
import jakarta.servlet.ServletConnection;
import org.apache.juli.logging.Log;
import org.apache.juli.logging.LogFactory;
import org.apache.tomcat.util.ExceptionUtils;
import org.apache.tomcat.util.res.StringManager;
public abstract class SocketWrapperBase<E> {
private static final Log log = LogFactory.getLog(SocketWrapperBase.class);
protected static final StringManager sm = StringManager.getManager(SocketWrapperBase.class);
/*
* At 100,000 connections a second there are enough IDs here for ~3,000,000
* years before it overflows (and then we have another 3,000,000 years
* before it gets back to zero).
*
* Local testing shows that 5 threads can obtain 60,000,000+ IDs a second
* from a single AtomicLong. That is about about 17ns per request. It does
* not appear that the introduction of this counter will cause a bottleneck
* for connection processing.
*/
private static final AtomicLong connectionIdGenerator = new AtomicLong(0);
private E socket;
private final AbstractEndpoint<E,?> endpoint;
private final ReentrantLock lock = new ReentrantLock();
protected final AtomicBoolean closed = new AtomicBoolean(false);
// Volatile because I/O and setting the timeout values occurs on a different
// thread to the thread checking the timeout.
private volatile long readTimeout = -1;
private volatile long writeTimeout = -1;
protected volatile IOException previousIOException = null;
private volatile int keepAliveLeft = 100;
private String negotiatedProtocol = null;
private final String connectionId;
/*
* Following cached for speed / reduced GC
*/
protected String localAddr = null;
protected String localName = null;
protected int localPort = -1;
protected String remoteAddr = null;
protected String remoteHost = null;
protected int remotePort = -1;
protected volatile ServletConnection servletConnection = null;
/**
* Used to record the first IOException that occurs during non-blocking
* read/writes that can't be usefully propagated up the stack since there is
* no user code or appropriate container code in the stack to handle it.
*/
private volatile IOException error = null;
/**
* The buffers used for communicating with the socket.
*/
protected volatile SocketBufferHandler socketBufferHandler = null;
/**
* The max size of the individual buffered write buffers
*/
protected int bufferedWriteSize = 64 * 1024; // 64k default write buffer
/**
* Additional buffer used for non-blocking writes. Non-blocking writes need
* to return immediately even if the data cannot be written immediately but
* the socket buffer may not be big enough to hold all of the unwritten
* data. This structure provides an additional buffer to hold the data until
* it can be written.
* Not that while the Servlet API only allows one non-blocking write at a
* time, due to buffering and the possible need to write HTTP headers, this
* layer may see multiple writes.
*/
protected final WriteBuffer nonBlockingWriteBuffer = new WriteBuffer(bufferedWriteSize);
/*
* Asynchronous operations.
*/
protected final Semaphore readPending;
protected volatile OperationState<?> readOperation = null;
protected final Semaphore writePending;
protected volatile OperationState<?> writeOperation = null;
/**
* The org.apache.coyote.Processor instance currently associated with the
* wrapper. Only populated when required to maintain wrapper<->Processor
* mapping between calls to
* {@link AbstractEndpoint.Handler#process(SocketWrapperBase, SocketEvent)}.
*/
private final AtomicReference<Object> currentProcessor = new AtomicReference<>();
public SocketWrapperBase(E socket, AbstractEndpoint<E,?> endpoint) {
this.socket = socket;
this.endpoint = endpoint;
if (endpoint.getUseAsyncIO() || needSemaphores()) {
readPending = new Semaphore(1);
writePending = new Semaphore(1);
} else {
readPending = null;
writePending = null;
}
connectionId = Long.toHexString(connectionIdGenerator.getAndIncrement());
}
public E getSocket() {
return socket;
}
protected void reset(E closedSocket) {
socket = closedSocket;
}
protected AbstractEndpoint<E,?> getEndpoint() {
return endpoint;
}
public ReentrantLock getLock() {
return lock;
}
public Object getCurrentProcessor() {
return currentProcessor.get();
}
public void setCurrentProcessor(Object currentProcessor) {
this.currentProcessor.set(currentProcessor);
}
public Object takeCurrentProcessor() {
return currentProcessor.getAndSet(null);
}
/**
* Transfers processing to a container thread.
*
* @param runnable The actions to process on a container thread
*
* @throws RejectedExecutionException If the runnable cannot be executed
*/
public void execute(Runnable runnable) {
Executor executor = endpoint.getExecutor();
if (!endpoint.isRunning() || executor == null) {
throw new RejectedExecutionException();
}
executor.execute(runnable);
}
public IOException getError() { return error; }
public void setError(IOException error) {
// Not perfectly thread-safe but good enough. Just needs to ensure that
// once this.error is non-null, it can never be null.
if (this.error != null) {
return;
}
this.error = error;
}
public void checkError() throws IOException {
if (error != null) {
throw error;
}
}
public String getNegotiatedProtocol() { return negotiatedProtocol; }
public void setNegotiatedProtocol(String negotiatedProtocol) {
this.negotiatedProtocol = negotiatedProtocol;
}
/**
* Set the timeout for reading. Values of zero or less will be changed to
* -1.
*
* @param readTimeout The timeout in milliseconds. A value of -1 indicates
* an infinite timeout.
*/
public void setReadTimeout(long readTimeout) {
if (readTimeout > 0) {
this.readTimeout = readTimeout;
} else {
this.readTimeout = -1;
}
}
public long getReadTimeout() {
return this.readTimeout;
}
/**
* Set the timeout for writing. Values of zero or less will be changed to
* -1.
*
* @param writeTimeout The timeout in milliseconds. A value of zero or less
* indicates an infinite timeout.
*/
public void setWriteTimeout(long writeTimeout) {
if (writeTimeout > 0) {
this.writeTimeout = writeTimeout;
} else {
this.writeTimeout = -1;
}
}
public long getWriteTimeout() {
return this.writeTimeout;
}
public void setKeepAliveLeft(int keepAliveLeft) { this.keepAliveLeft = keepAliveLeft; }
public int decrementKeepAlive() { return (--keepAliveLeft); }
public String getRemoteHost() {
if (remoteHost == null) {
populateRemoteHost();
}
return remoteHost;
}
protected abstract void populateRemoteHost();
public String getRemoteAddr() {
if (remoteAddr == null) {
populateRemoteAddr();
}
return remoteAddr;
}
protected abstract void populateRemoteAddr();
public int getRemotePort() {
if (remotePort == -1) {
populateRemotePort();
}
return remotePort;
}
protected abstract void populateRemotePort();
public String getLocalName() {
if (localName == null) {
populateLocalName();
}
return localName;
}
protected abstract void populateLocalName();
public String getLocalAddr() {
if (localAddr == null) {
populateLocalAddr();
}
return localAddr;
}
protected abstract void populateLocalAddr();
public int getLocalPort() {
if (localPort == -1) {
populateLocalPort();
}
return localPort;
}
protected abstract void populateLocalPort();
public SocketBufferHandler getSocketBufferHandler() { return socketBufferHandler; }
public boolean hasDataToRead() {
// Return true because it is always safe to make a read attempt
return true;
}
public boolean hasDataToWrite() {
return !socketBufferHandler.isWriteBufferEmpty() || !nonBlockingWriteBuffer.isEmpty();
}
/**
* Checks to see if there are any writes pending and if there are calls
* {@link #registerWriteInterest()} to trigger a callback once the pending
* writes have completed.
* <p>
* Note: Once this method has returned <code>false</code> it <b>MUST NOT</b>
* be called again until the pending write has completed and the
* callback has been fired.
* TODO: Modify {@link #registerWriteInterest()} so the above
* restriction is enforced there rather than relying on the caller.
*
* @return <code>true</code> if no writes are pending and data can be
* written otherwise <code>false</code>
*/
public boolean isReadyForWrite() {
boolean result = canWrite();
if (!result) {
registerWriteInterest();
}
return result;
}
public boolean canWrite() {
if (socketBufferHandler == null) {
throw new IllegalStateException(sm.getString("socket.closed"));
}
return socketBufferHandler.isWriteBufferWritable() && nonBlockingWriteBuffer.isEmpty();
}
/**
* Overridden for debug purposes. No guarantees are made about the format of
* this message which may vary significantly between point releases.
* <p>
* {@inheritDoc}
*/
@Override
public String toString() {
return super.toString() + ":" + String.valueOf(socket);
}
public abstract int read(boolean block, byte[] b, int off, int len) throws IOException;
public abstract int read(boolean block, ByteBuffer to) throws IOException;
public abstract boolean isReadyForRead() throws IOException;
public abstract void setAppReadBufHandler(ApplicationBufferHandler handler);
protected int populateReadBuffer(byte[] b, int off, int len) {
socketBufferHandler.configureReadBufferForRead();
ByteBuffer readBuffer = socketBufferHandler.getReadBuffer();
int remaining = readBuffer.remaining();
// Is there enough data in the read buffer to satisfy this request?
// Copy what data there is in the read buffer to the byte array
if (remaining > 0) {
remaining = Math.min(remaining, len);
readBuffer.get(b, off, remaining);
if (log.isTraceEnabled()) {
log.trace("Socket: [" + this + "], Read from buffer: [" + remaining + "]");
}
}
return remaining;
}
protected int populateReadBuffer(ByteBuffer to) {
// Is there enough data in the read buffer to satisfy this request?
// Copy what data there is in the read buffer to the byte array
socketBufferHandler.configureReadBufferForRead();
int nRead = transfer(socketBufferHandler.getReadBuffer(), to);
if (log.isTraceEnabled()) {
log.trace("Socket: [" + this + "], Read from buffer: [" + nRead + "]");
}
return nRead;
}
/**
* Return input that has been read to the input buffer for re-reading by the
* correct component. There are times when a component may read more data
* than it needs before it passes control to another component. One example
* of this is during HTTP upgrade. If an (arguably misbehaving client) sends
* data associated with the upgraded protocol before the HTTP upgrade
* completes, the HTTP handler may read it. This method provides a way for
* that data to be returned so it can be processed by the correct component.
*
* @param returnedInput The input to return to the input buffer.
*/
public void unRead(ByteBuffer returnedInput) {
if (returnedInput != null) {
socketBufferHandler.unReadReadBuffer(returnedInput);
}
}
/**
* Close the socket wrapper.
*/
public void close() {
if (closed.compareAndSet(false, true)) {
try {
getEndpoint().getHandler().release(this);
} catch (Throwable e) {
ExceptionUtils.handleThrowable(e);
if (log.isDebugEnabled()) {
log.error(sm.getString("endpoint.debug.handlerRelease"), e);
}
} finally {
getEndpoint().countDownConnection();
doClose();
}
}
}
/**
* Perform the actual close. The closed atomic boolean guarantees this will
* be called only once per wrapper.
*/
protected abstract void doClose();
/**
* @return true if the wrapper has been closed
*/
public boolean isClosed() {
return closed.get();
}
/**
* Writes the provided data to the socket write buffer. If the socket write
* buffer fills during the write, the content of the socket write buffer is
* written to the network and this method starts to fill the socket write
* buffer again. Depending on the size of the data to write, there may be
* multiple writes to the network.
* <p>
* Non-blocking writes must return immediately and the byte array holding
* the data to be written must be immediately available for re-use. It may
* not be possible to write sufficient data to the network to allow this to
* happen. In this case data that cannot be written to the network and
* cannot be held by the socket buffer is stored in the non-blocking write
* buffer.
* <p>
* Note: There is an implementation assumption that, before switching from
* non-blocking writes to blocking writes, any data remaining in the
* non-blocking write buffer will have been written to the network.
*
* @param block <code>true</code> if a blocking write should be used,
* otherwise a non-blocking write will be used
* @param buf The byte array containing the data to be written
* @param off The offset within the byte array of the data to be written
* @param len The length of the data to be written
*
* @throws IOException If an IO error occurs during the write
*/
public final void write(boolean block, byte[] buf, int off, int len) throws IOException {
if (len == 0 || buf == null) {
return;
}
/*
* While the implementations for blocking and non-blocking writes are
* very similar they have been split into separate methods:
* - To allow sub-classes to override them individually. NIO2, for
* example, overrides the non-blocking write but not the blocking
* write.
* - To enable a marginally more efficient implemented for blocking
* writes which do not require the additional checks related to the
* use of the non-blocking write buffer
*/
if (block) {
writeBlocking(buf, off, len);
} else {
writeNonBlocking(buf, off, len);
}
}
/**
* Writes the provided data to the socket write buffer. If the socket write
* buffer fills during the write, the content of the socket write buffer is
* written to the network and this method starts to fill the socket write
* buffer again. Depending on the size of the data to write, there may be
* multiple writes to the network.
* <p>
* Non-blocking writes must return immediately and the ByteBuffer holding
* the data to be written must be immediately available for re-use. It may
* not be possible to write sufficient data to the network to allow this to
* happen. In this case data that cannot be written to the network and
* cannot be held by the socket buffer is stored in the non-blocking write
* buffer.
* <p>
* Note: There is an implementation assumption that, before switching from
* non-blocking writes to blocking writes, any data remaining in the
* non-blocking write buffer will have been written to the network.
*
* @param block <code>true</code> if a blocking write should be used,
* otherwise a non-blocking write will be used
* @param from The ByteBuffer containing the data to be written
*
* @throws IOException If an IO error occurs during the write
*/
public final void write(boolean block, ByteBuffer from) throws IOException {
if (from == null || from.remaining() == 0) {
return;
}
/*
* While the implementations for blocking and non-blocking writes are
* very similar they have been split into separate methods:
* - To allow sub-classes to override them individually. NIO2, for
* example, overrides the non-blocking write but not the blocking
* write.
* - To enable a marginally more efficient implemented for blocking
* writes which do not require the additional checks related to the
* use of the non-blocking write buffer
*/
if (block) {
writeBlocking(from);
} else {
writeNonBlocking(from);
}
}
/**
* Writes the provided data to the socket write buffer. If the socket write
* buffer fills during the write, the content of the socket write buffer is
* written to the network using a blocking write. Once that blocking write
* is complete, this method starts to fill the socket write buffer again.
* Depending on the size of the data to write, there may be multiple writes
* to the network. On completion of this method there will always be space
* remaining in the socket write buffer.
*
* @param buf The byte array containing the data to be written
* @param off The offset within the byte array of the data to be written
* @param len The length of the data to be written
*
* @throws IOException If an IO error occurs during the write
*/
protected void writeBlocking(byte[] buf, int off, int len) throws IOException {
if (len > 0) {
socketBufferHandler.configureWriteBufferForWrite();
int thisTime = transfer(buf, off, len, socketBufferHandler.getWriteBuffer());
len -= thisTime;
while (len > 0) {
off += thisTime;
doWrite(true);
socketBufferHandler.configureWriteBufferForWrite();
thisTime = transfer(buf, off, len, socketBufferHandler.getWriteBuffer());
len -= thisTime;
}
}
}
/**
* Writes the provided data to the socket write buffer. If the socket write
* buffer fills during the write, the content of the socket write buffer is
* written to the network using a blocking write. Once that blocking write
* is complete, this method starts to fill the socket write buffer again.
* Depending on the size of the data to write, there may be multiple writes
* to the network. On completion of this method there will always be space
* remaining in the socket write buffer.
*
* @param from The ByteBuffer containing the data to be written
*
* @throws IOException If an IO error occurs during the write
*/
protected void writeBlocking(ByteBuffer from) throws IOException {
if (from.hasRemaining()) {
socketBufferHandler.configureWriteBufferForWrite();
transfer(from, socketBufferHandler.getWriteBuffer());
while (from.hasRemaining()) {
doWrite(true);
socketBufferHandler.configureWriteBufferForWrite();
transfer(from, socketBufferHandler.getWriteBuffer());
}
}
}
/**
* Transfers the data to the socket write buffer (writing that data to the
* socket if the buffer fills up using a non-blocking write) until either
* all the data has been transferred and space remains in the socket write
* buffer or a non-blocking write leaves data in the socket write buffer.
* After an incomplete write, any data remaining to be transferred to the
* socket write buffer will be copied to the socket write buffer. If the
* remaining data is too big for the socket write buffer, the socket write
* buffer will be filled and the additional data written to the non-blocking
* write buffer.
*
* @param buf The byte array containing the data to be written
* @param off The offset within the byte array of the data to be written
* @param len The length of the data to be written
*
* @throws IOException If an IO error occurs during the write
*/
protected void writeNonBlocking(byte[] buf, int off, int len) throws IOException {
if (len > 0 && nonBlockingWriteBuffer.isEmpty()
&& socketBufferHandler.isWriteBufferWritable()) {
socketBufferHandler.configureWriteBufferForWrite();
int thisTime = transfer(buf, off, len, socketBufferHandler.getWriteBuffer());
len -= thisTime;
while (len > 0) {
off = off + thisTime;
doWrite(false);
if (len > 0 && socketBufferHandler.isWriteBufferWritable()) {
socketBufferHandler.configureWriteBufferForWrite();
thisTime = transfer(buf, off, len, socketBufferHandler.getWriteBuffer());
} else {
// Didn't write any data in the last non-blocking write.
// Therefore the write buffer will still be full. Nothing
// else to do here. Exit the loop.
break;
}
len -= thisTime;
}
}
if (len > 0) {
// Remaining data must be buffered
nonBlockingWriteBuffer.add(buf, off, len);
}
}
/**
* Transfers the data to the socket write buffer (writing that data to the
* socket if the buffer fills up using a non-blocking write) until either
* all the data has been transferred and space remains in the socket write
* buffer or a non-blocking write leaves data in the socket write buffer.
* After an incomplete write, any data remaining to be transferred to the
* socket write buffer will be copied to the socket write buffer. If the
* remaining data is too big for the socket write buffer, the socket write
* buffer will be filled and the additional data written to the non-blocking
* write buffer.
*
* @param from The ByteBuffer containing the data to be written
*
* @throws IOException If an IO error occurs during the write
*/
protected void writeNonBlocking(ByteBuffer from)
throws IOException {
if (from.hasRemaining() && nonBlockingWriteBuffer.isEmpty()
&& socketBufferHandler.isWriteBufferWritable()) {
writeNonBlockingInternal(from);
}
if (from.hasRemaining()) {
// Remaining data must be buffered
nonBlockingWriteBuffer.add(from);
}
}
/**
* Separate method so it can be re-used by the socket write buffer to write
* data to the network
*
* @param from The ByteBuffer containing the data to be written
*
* @throws IOException If an IO error occurs during the write
*/
protected void writeNonBlockingInternal(ByteBuffer from) throws IOException {
socketBufferHandler.configureWriteBufferForWrite();
transfer(from, socketBufferHandler.getWriteBuffer());
while (from.hasRemaining()) {
doWrite(false);
if (socketBufferHandler.isWriteBufferWritable()) {
socketBufferHandler.configureWriteBufferForWrite();
transfer(from, socketBufferHandler.getWriteBuffer());
} else {
break;
}
}
}
/**
* Writes as much data as possible from any that remains in the buffers.
*
* @param block <code>true</code> if a blocking write should be used,
* otherwise a non-blocking write will be used
*
* @return <code>true</code> if data remains to be flushed after this method
* completes, otherwise <code>false</code>. In blocking mode
* therefore, the return value should always be <code>false</code>
*
* @throws IOException If an IO error occurs during the write
*/
public boolean flush(boolean block) throws IOException {
boolean result = false;
if (block) {
// A blocking flush will always empty the buffer.
flushBlocking();
} else {
result = flushNonBlocking();
}
return result;
}
/**
* Writes all remaining data from the buffers and blocks until the write is
* complete.
*
* @throws IOException If an IO error occurs during the write
*/
protected void flushBlocking() throws IOException {
doWrite(true);
if (!nonBlockingWriteBuffer.isEmpty()) {
nonBlockingWriteBuffer.write(this, true);
if (!socketBufferHandler.isWriteBufferEmpty()) {
doWrite(true);
}
}
}
/**
* Writes as much data as possible from any that remains in the buffers.
*
* @return <code>true</code> if data remains to be flushed after this method
* completes, otherwise <code>false</code>.
*
* @throws IOException If an IO error occurs during the write
*/
protected abstract boolean flushNonBlocking() throws IOException;
/**
* Write the contents of the socketWriteBuffer to the socket. For blocking
* writes either then entire contents of the buffer will be written or an
* IOException will be thrown. Partial blocking writes will not occur.
*
* @param block Should the write be blocking or not?
*
* @throws IOException If an I/O error such as a timeout occurs during the
* write
*/
protected void doWrite(boolean block) throws IOException {
socketBufferHandler.configureWriteBufferForRead();
doWrite(block, socketBufferHandler.getWriteBuffer());
}
/**
* Write the contents of the ByteBuffer to the socket. For blocking writes
* either then entire contents of the buffer will be written or an
* IOException will be thrown. Partial blocking writes will not occur.
*
* @param block Should the write be blocking or not?
* @param from the ByteBuffer containing the data to be written
*
* @throws IOException If an I/O error such as a timeout occurs during the
* write
*/
protected abstract void doWrite(boolean block, ByteBuffer from) throws IOException;
public void processSocket(SocketEvent socketStatus, boolean dispatch) {
endpoint.processSocket(this, socketStatus, dispatch);
}
public abstract void registerReadInterest();
public abstract void registerWriteInterest();
public abstract SendfileDataBase createSendfileData(String filename, long pos, long length);
/**
* Starts the sendfile process. It is expected that if the sendfile process
* does not complete during this call and does not report an error, that the
* caller <b>will not</b> add the socket to the poller (or equivalent). That
* is the responsibility of this method.
*
* @param sendfileData Data representing the file to send
*
* @return The state of the sendfile process after the first write.
*/
public abstract SendfileState processSendfile(SendfileDataBase sendfileData);
/**
* Require the client to perform CLIENT-CERT authentication if it hasn't
* already done so.
*
* @param sslSupport The SSL/TLS support instance currently being used by
* the connection that may need updating after the client
* authentication
*
* @throws IOException If authentication is required then there will be I/O
* with the client and this exception will be thrown if
* that goes wrong
*/
public abstract void doClientAuth(SSLSupport sslSupport) throws IOException;
/**
* Obtain an SSLSupport instance for this socket.
*
* @return An SSLSupport instance for this socket.
*/
public abstract SSLSupport getSslSupport();
// ------------------------------------------------------- NIO 2 style APIs
public enum BlockingMode {
/**
* The operation will not block. If there are pending operations,
* the operation will throw a pending exception.
*/
CLASSIC,
/**
* The operation will not block. If there are pending operations,
* the operation will return CompletionState.NOT_DONE.
*/
NON_BLOCK,
/**
* The operation will block until pending operations are completed, but
* will not block after performing it.
*/
SEMI_BLOCK,
/**
* The operation will block until completed.
*/
BLOCK
}
public enum CompletionState {
/**
* Operation is still pending.
*/
PENDING,
/**
* Operation was pending and non blocking.
*/
NOT_DONE,
/**
* The operation completed inline.
*/
INLINE,
/**
* The operation completed inline but failed.
*/
ERROR,
/**
* The operation completed, but not inline.
*/
DONE
}
public enum CompletionHandlerCall {
/**
* Operation should continue, the completion handler shouldn't be
* called.
*/
CONTINUE,
/**
* The operation completed but the completion handler shouldn't be
* called.
*/
NONE,
/**
* The operation is complete, the completion handler should be
* called.
*/
DONE
}
public interface CompletionCheck {
/**
* Determine what call, if any, should be made to the completion
* handler.
*
* @param state of the operation (done or done in-line since the
* IO call is done)
* @param buffers ByteBuffer[] that has been passed to the
* original IO call
* @param offset that has been passed to the original IO call
* @param length that has been passed to the original IO call
*
* @return The call, if any, to make to the completion handler
*/
CompletionHandlerCall callHandler(CompletionState state, ByteBuffer[] buffers,
int offset, int length);
}
/**
* This utility CompletionCheck will cause the write to fully write
* all remaining data. If the operation completes inline, the
* completion handler will not be called.
*/
public static final CompletionCheck COMPLETE_WRITE = new CompletionCheck() {
@Override
public CompletionHandlerCall callHandler(CompletionState state, ByteBuffer[] buffers,
int offset, int length) {
for (int i = 0; i < length; i++) {
if (buffers[offset + i].hasRemaining()) {
return CompletionHandlerCall.CONTINUE;
}
}
return (state == CompletionState.DONE) ? CompletionHandlerCall.DONE
: CompletionHandlerCall.NONE;
}
};
/**
* This utility CompletionCheck will cause the write to fully write
* all remaining data. The completion handler will then be called.
*/
public static final CompletionCheck COMPLETE_WRITE_WITH_COMPLETION = new CompletionCheck() {
@Override
public CompletionHandlerCall callHandler(CompletionState state, ByteBuffer[] buffers,
int offset, int length) {
for (int i = 0; i < length; i++) {
if (buffers[offset + i].hasRemaining()) {
return CompletionHandlerCall.CONTINUE;
}
}
return CompletionHandlerCall.DONE;
}
};
/**
* This utility CompletionCheck will cause the completion handler
* to be called once some data has been read. If the operation
* completes inline, the completion handler will not be called.
*/
public static final CompletionCheck READ_DATA = new CompletionCheck() {
@Override
public CompletionHandlerCall callHandler(CompletionState state, ByteBuffer[] buffers,
int offset, int length) {
return (state == CompletionState.DONE) ? CompletionHandlerCall.DONE
: CompletionHandlerCall.NONE;
}
};
/**
* This utility CompletionCheck will cause the completion handler
* to be called once the given buffers are full. The completion
* handler will then be called.
*/
public static final CompletionCheck COMPLETE_READ_WITH_COMPLETION = COMPLETE_WRITE_WITH_COMPLETION;
/**
* This utility CompletionCheck will cause the completion handler
* to be called once the given buffers are full. If the operation
* completes inline, the completion handler will not be called.
*/
public static final CompletionCheck COMPLETE_READ = COMPLETE_WRITE;
/**
* Internal state tracker for vectored operations.
*/
protected abstract class OperationState<A> implements Runnable {
protected final boolean read;
protected final ByteBuffer[] buffers;
protected final int offset;
protected final int length;
protected final A attachment;
protected final long timeout;
protected final TimeUnit unit;
protected final BlockingMode block;
protected final CompletionCheck check;
protected final CompletionHandler<Long, ? super A> handler;
protected final Semaphore semaphore;
protected final VectoredIOCompletionHandler<A> completion;
protected final AtomicBoolean callHandler;
protected OperationState(boolean read, ByteBuffer[] buffers, int offset, int length,
BlockingMode block, long timeout, TimeUnit unit, A attachment,
CompletionCheck check, CompletionHandler<Long, ? super A> handler,
Semaphore semaphore, VectoredIOCompletionHandler<A> completion) {
this.read = read;
this.buffers = buffers;
this.offset = offset;
this.length = length;
this.block = block;
this.timeout = timeout;
this.unit = unit;
this.attachment = attachment;
this.check = check;
this.handler = handler;
this.semaphore = semaphore;
this.completion = completion;
callHandler = (handler != null) ? new AtomicBoolean(true) : null;
}
protected volatile long nBytes = 0;
protected volatile CompletionState state = CompletionState.PENDING;
protected boolean completionDone = true;
/**
* @return true if the operation is still inline, false if the operation
* is running on a thread that is not the original caller
*/
protected abstract boolean isInline();
protected boolean hasOutboundRemaining() {
// NIO2 and APR never have remaining outbound data when the
// completion handler is called. NIO needs to override this.
return false;
}
/**
* Process the operation using the connector executor.
* @return true if the operation was accepted, false if the executor
* rejected execution
*/
protected boolean process() {
try {
getEndpoint().getExecutor().execute(this);
return true;
} catch (RejectedExecutionException ree) {
log.warn(sm.getString("endpoint.executor.fail", SocketWrapperBase.this) , ree);
} 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;
}
/**
* Start the operation, this will typically call run.
*/
protected void start() {
run();
}
/**
* End the operation.
*/
protected void end() {
}
}
/**
* Completion handler for vectored operations. This will check the completion of the operation,
* then either continue or call the user provided completion handler.
*/
protected class VectoredIOCompletionHandler<A> implements CompletionHandler<Long, OperationState<A>> {
@Override
public void completed(Long nBytes, OperationState<A> state) {
if (nBytes.longValue() < 0) {
failed(new EOFException(), state);
} else {
state.nBytes += nBytes.longValue();
CompletionState currentState = state.isInline() ? CompletionState.INLINE : CompletionState.DONE;
boolean complete = true;
boolean completion = true;
if (state.check != null) {
CompletionHandlerCall call = state.check.callHandler(currentState, state.buffers, state.offset, state.length);
if (call == CompletionHandlerCall.CONTINUE || (!state.read && state.hasOutboundRemaining())) {
complete = false;
} else if (call == CompletionHandlerCall.NONE) {
completion = false;
}
}
if (complete) {
boolean notify = false;
if (state.read) {
readOperation = null;
} else {
writeOperation = null;
}
// Semaphore must be released after [read|write]Operation is cleared
// to ensure that the next thread to hold the semaphore hasn't
// written a new value to [read|write]Operation by the time it is
// cleared.
state.semaphore.release();
if (state.block == BlockingMode.BLOCK && currentState != CompletionState.INLINE) {
notify = true;
} else {
state.state = currentState;
}
state.end();
if (completion && state.handler != null && state.callHandler.compareAndSet(true, false)) {
state.handler.completed(Long.valueOf(state.nBytes), state.attachment);
}
synchronized (state) {
state.completionDone = true;
if (notify) {
state.state = currentState;
state.notify();
}
}
} else {
synchronized (state) {
state.completionDone = true;
}
state.run();
}
}
}
@Override
public void failed(Throwable exc, OperationState<A> state) {
IOException ioe = null;
if (exc instanceof InterruptedByTimeoutException) {
ioe = new SocketTimeoutException();
exc = ioe;
} else if (exc instanceof IOException) {
ioe = (IOException) exc;
}
setError(ioe);
boolean notify = false;
if (state.read) {
readOperation = null;
} else {
writeOperation = null;
}
// Semaphore must be released after [read|write]Operation is cleared
// to ensure that the next thread to hold the semaphore hasn't
// written a new value to [read|write]Operation by the time it is
// cleared.
state.semaphore.release();
if (state.block == BlockingMode.BLOCK) {
notify = true;
} else {
state.state = state.isInline() ? CompletionState.ERROR : CompletionState.DONE;
}
state.end();
if (state.handler != null && state.callHandler.compareAndSet(true, false)) {
state.handler.failed(exc, state.attachment);
}
synchronized (state) {
state.completionDone = true;
if (notify) {
state.state = state.isInline() ? CompletionState.ERROR : CompletionState.DONE;
state.notify();
}
}
}
}
/**
* Allows using NIO2 style read/write.
*
* @return {@code true} if the connector has the capability enabled
*/
public boolean hasAsyncIO() {
// The semaphores are only created if async IO is enabled
return (readPending != null);
}
/**
* Allows indicating if the connector needs semaphores.
*
* @return This default implementation always returns {@code false}
*/
public boolean needSemaphores() {
return false;
}
/**
* Allows indicating if the connector supports per operation timeout.
*
* @return This default implementation always returns {@code false}
*/
public boolean hasPerOperationTimeout() {
return false;
}
/**
* Allows checking if an asynchronous read operation is currently pending.
* @return <code>true</code> if the endpoint supports asynchronous IO and
* a read operation is being processed asynchronously
*/
public boolean isReadPending() {
return false;
}
/**
* Allows checking if an asynchronous write operation is currently pending.
* @return <code>true</code> if the endpoint supports asynchronous IO and
* a write operation is being processed asynchronously
*/
public boolean isWritePending() {
return false;
}
/**
* Scatter read. The completion handler will be called once some
* data has been read or an error occurred. The default NIO2
* behavior is used: the completion handler will be called as soon
* as some data has been read, even if the read has completed inline.
*
* @param timeout timeout duration for the read
* @param unit units for the timeout duration
* @param attachment an object to attach to the I/O operation that will be
* used when calling the completion handler
* @param handler to call when the IO is complete
* @param dsts buffers
* @param <A> The attachment type
* @return the completion state (done, done inline, or still pending)
*/
public final <A> CompletionState read(long timeout, TimeUnit unit, A attachment,
CompletionHandler<Long, ? super A> handler, ByteBuffer... dsts) {
if (dsts == null) {
throw new IllegalArgumentException();
}
return read(dsts, 0, dsts.length, BlockingMode.CLASSIC, timeout, unit, attachment, null, handler);
}
/**
* Scatter read. The completion handler will be called once some
* data has been read or an error occurred. If a CompletionCheck
* object has been provided, the completion handler will only be
* called if the callHandler method returned true. If no
* CompletionCheck object has been provided, the default NIO2
* behavior is used: the completion handler will be called as soon
* as some data has been read, even if the read has completed inline.
*
* @param block is the blocking mode that will be used for this operation
* @param timeout timeout duration for the read
* @param unit units for the timeout duration
* @param attachment an object to attach to the I/O operation that will be
* used when calling the completion handler
* @param check for the IO operation completion
* @param handler to call when the IO is complete
* @param dsts buffers
* @param <A> The attachment type
* @return the completion state (done, done inline, or still pending)
*/
public final <A> CompletionState read(BlockingMode block, long timeout,
TimeUnit unit, A attachment, CompletionCheck check,
CompletionHandler<Long, ? super A> handler, ByteBuffer... dsts) {
if (dsts == null) {
throw new IllegalArgumentException();
}
return read(dsts, 0, dsts.length, block, timeout, unit, attachment, check, handler);
}
/**
* Scatter read. The completion handler will be called once some
* data has been read or an error occurred. If a CompletionCheck
* object has been provided, the completion handler will only be
* called if the callHandler method returned true. If no
* CompletionCheck object has been provided, the default NIO2
* behavior is used: the completion handler will be called as soon
* as some data has been read, even if the read has completed inline.
*
* @param dsts buffers
* @param offset in the buffer array
* @param length in the buffer array
* @param block is the blocking mode that will be used for this operation
* @param timeout timeout duration for the read
* @param unit units for the timeout duration
* @param attachment an object to attach to the I/O operation that will be
* used when calling the completion handler
* @param check for the IO operation completion
* @param handler to call when the IO is complete
* @param <A> The attachment type
* @return the completion state (done, done inline, or still pending)
*/
public final <A> CompletionState read(ByteBuffer[] dsts, int offset, int length,
BlockingMode block, long timeout, TimeUnit unit, A attachment,
CompletionCheck check, CompletionHandler<Long, ? super A> handler) {
return vectoredOperation(true, dsts, offset, length, block, timeout, unit, attachment, check, handler);
}
/**
* Gather write. The completion handler will be called once some
* data has been written or an error occurred. The default NIO2
* behavior is used: the completion handler will be called, even
* if the write is incomplete and data remains in the buffers, or
* if the write completed inline.
*
* @param timeout timeout duration for the write
* @param unit units for the timeout duration
* @param attachment an object to attach to the I/O operation that will be
* used when calling the completion handler
* @param handler to call when the IO is complete
* @param srcs buffers
* @param <A> The attachment type
* @return the completion state (done, done inline, or still pending)
*/
public final <A> CompletionState write(long timeout, TimeUnit unit, A attachment,
CompletionHandler<Long, ? super A> handler, ByteBuffer... srcs) {
if (srcs == null) {
throw new IllegalArgumentException();
}
return write(srcs, 0, srcs.length, BlockingMode.CLASSIC, timeout, unit, attachment, null, handler);
}
/**
* Gather write. The completion handler will be called once some
* data has been written or an error occurred. If a CompletionCheck
* object has been provided, the completion handler will only be
* called if the callHandler method returned true. If no
* CompletionCheck object has been provided, the default NIO2
* behavior is used: the completion handler will be called, even
* if the write is incomplete and data remains in the buffers, or
* if the write completed inline.
*
* @param block is the blocking mode that will be used for this operation
* @param timeout timeout duration for the write
* @param unit units for the timeout duration
* @param attachment an object to attach to the I/O operation that will be
* used when calling the completion handler
* @param check for the IO operation completion
* @param handler to call when the IO is complete
* @param srcs buffers
* @param <A> The attachment type
* @return the completion state (done, done inline, or still pending)
*/
public final <A> CompletionState write(BlockingMode block, long timeout,
TimeUnit unit, A attachment, CompletionCheck check,
CompletionHandler<Long, ? super A> handler, ByteBuffer... srcs) {
if (srcs == null) {
throw new IllegalArgumentException();
}
return write(srcs, 0, srcs.length, block, timeout, unit, attachment, check, handler);
}
/**
* Gather write. The completion handler will be called once some
* data has been written or an error occurred. If a CompletionCheck
* object has been provided, the completion handler will only be
* called if the callHandler method returned true. If no
* CompletionCheck object has been provided, the default NIO2
* behavior is used: the completion handler will be called, even
* if the write is incomplete and data remains in the buffers, or
* if the write completed inline.
*
* @param srcs buffers
* @param offset in the buffer array
* @param length in the buffer array
* @param block is the blocking mode that will be used for this operation
* @param timeout timeout duration for the write
* @param unit units for the timeout duration
* @param attachment an object to attach to the I/O operation that will be
* used when calling the completion handler
* @param check for the IO operation completion
* @param handler to call when the IO is complete
* @param <A> The attachment type
* @return the completion state (done, done inline, or still pending)
*/
public final <A> CompletionState write(ByteBuffer[] srcs, int offset, int length,
BlockingMode block, long timeout, TimeUnit unit, A attachment,
CompletionCheck check, CompletionHandler<Long, ? super A> handler) {
return vectoredOperation(false, srcs, offset, length, block, timeout, unit, attachment, check, handler);
}
/**
* Vectored operation. The completion handler will be called once
* the operation is complete or an error occurred. If a CompletionCheck
* object has been provided, the completion handler will only be
* called if the callHandler method returned true. If no
* CompletionCheck object has been provided, the default NIO2
* behavior is used: the completion handler will be called, even
* if the operation is incomplete, or if the operation completed inline.
*
* @param read true if the operation is a read, false if it is a write
* @param buffers buffers
* @param offset in the buffer array
* @param length in the buffer array
* @param block is the blocking mode that will be used for this operation
* @param timeout timeout duration for the write
* @param unit units for the timeout duration
* @param attachment an object to attach to the I/O operation that will be
* used when calling the completion handler
* @param check for the IO operation completion
* @param handler to call when the IO is complete
* @param <A> The attachment type
* @return the completion state (done, done inline, or still pending)
*/
protected final <A> CompletionState vectoredOperation(boolean read,
ByteBuffer[] buffers, int offset, int length,
BlockingMode block, long timeout, TimeUnit unit, A attachment,
CompletionCheck check, CompletionHandler<Long, ? super A> handler) {
IOException ioe = getError();
if (ioe != null) {
handler.failed(ioe, attachment);
return CompletionState.ERROR;
}
if (timeout == -1) {
timeout = AbstractEndpoint.toTimeout(read ? getReadTimeout() : getWriteTimeout());
unit = TimeUnit.MILLISECONDS;
} else if (!hasPerOperationTimeout() && (unit.toMillis(timeout) != (read ? getReadTimeout() : getWriteTimeout()))) {
if (read) {
setReadTimeout(unit.toMillis(timeout));
} else {
setWriteTimeout(unit.toMillis(timeout));
}
}
if (block == BlockingMode.BLOCK || block == BlockingMode.SEMI_BLOCK) {
try {
if (read ? !readPending.tryAcquire(timeout, unit) : !writePending.tryAcquire(timeout, unit)) {
handler.failed(new SocketTimeoutException(), attachment);
return CompletionState.ERROR;
}
} catch (InterruptedException e) {
handler.failed(e, attachment);
return CompletionState.ERROR;
}
} else {
if (read ? !readPending.tryAcquire() : !writePending.tryAcquire()) {
if (block == BlockingMode.NON_BLOCK) {
return CompletionState.NOT_DONE;
} else {
handler.failed(read ? new ReadPendingException() : new WritePendingException(), attachment);
return CompletionState.ERROR;
}
}
}
VectoredIOCompletionHandler<A> completion = new VectoredIOCompletionHandler<>();
OperationState<A> state = newOperationState(read, buffers, offset, length, block, timeout, unit,
attachment, check, handler, read ? readPending : writePending, completion);
if (read) {
readOperation = state;
} else {
writeOperation = state;
}
state.start();
if (block == BlockingMode.BLOCK) {
synchronized (state) {
if (state.state == CompletionState.PENDING) {
try {
state.wait(unit.toMillis(timeout));
if (state.state == CompletionState.PENDING) {
if (handler != null && state.callHandler.compareAndSet(true, false)) {
handler.failed(new SocketTimeoutException(getTimeoutMsg(read)), attachment);
}
return CompletionState.ERROR;
}
} catch (InterruptedException e) {
if (handler != null && state.callHandler.compareAndSet(true, false)) {
handler.failed(new SocketTimeoutException(getTimeoutMsg(read)), attachment);
}
return CompletionState.ERROR;
}
}
}
}
return state.state;
}
private String getTimeoutMsg(boolean read) {
if (read) {
return sm.getString("socketWrapper.readTimeout");
} else {
return sm.getString("socketWrapper.writeTimeout");
}
}
protected abstract <A> OperationState<A> newOperationState(boolean read,
ByteBuffer[] buffers, int offset, int length,
BlockingMode block, long timeout, TimeUnit unit, A attachment,
CompletionCheck check, CompletionHandler<Long, ? super A> handler,
Semaphore semaphore, VectoredIOCompletionHandler<A> completion);
// --------------------------------------------------------- Utility methods
protected static int transfer(byte[] from, int offset, int length, ByteBuffer to) {
int max = Math.min(length, to.remaining());
if (max > 0) {
to.put(from, offset, max);
}
return max;
}
protected static int transfer(ByteBuffer from, ByteBuffer to) {
int max = Math.min(from.remaining(), to.remaining());
if (max > 0) {
int fromLimit = from.limit();
from.limit(from.position() + max);
to.put(from);
from.limit(fromLimit);
}
return max;
}
protected static boolean buffersArrayHasRemaining(ByteBuffer[] buffers, int offset, int length) {
for (int pos = offset; pos < offset + length; pos++) {
if (buffers[pos].hasRemaining()) {
return true;
}
}
return false;
}
// -------------------------------------------------------------- ID methods
public ServletConnection getServletConnection(String protocol, String protocolConnectionId) {
if (servletConnection == null) {
servletConnection = new ServletConnectionImpl(
connectionId, protocol, protocolConnectionId, endpoint.isSSLEnabled());
}
return servletConnection;
}
}