io.netty.channel.socket.nio.NioSocketChannel Maven / Gradle / Ivy
The newest version!
/*
* Copyright 2012 The Netty Project
*
* The Netty Project 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 io.netty.channel.socket.nio;
import io.netty.buffer.ByteBuf;
import io.netty.channel.Channel;
import io.netty.channel.ChannelException;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelOption;
import io.netty.channel.ChannelOutboundBuffer;
import io.netty.channel.ChannelPromise;
import io.netty.channel.EventLoop;
import io.netty.channel.FileRegion;
import io.netty.channel.RecvByteBufAllocator;
import io.netty.channel.nio.AbstractNioByteChannel;
import io.netty.channel.socket.DefaultSocketChannelConfig;
import io.netty.channel.socket.ServerSocketChannel;
import io.netty.channel.socket.SocketChannelConfig;
import io.netty.util.concurrent.GlobalEventExecutor;
import io.netty.util.internal.PlatformDependent;
import io.netty.util.internal.SocketUtils;
import io.netty.util.internal.SuppressJava6Requirement;
import io.netty.util.internal.UnstableApi;
import io.netty.util.internal.logging.InternalLogger;
import io.netty.util.internal.logging.InternalLoggerFactory;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.net.SocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.SelectionKey;
import java.nio.channels.SocketChannel;
import java.nio.channels.spi.SelectorProvider;
import java.util.Map;
import java.util.concurrent.Executor;
import static io.netty.channel.internal.ChannelUtils.MAX_BYTES_PER_GATHERING_WRITE_ATTEMPTED_LOW_THRESHOLD;
/**
* {@link io.netty.channel.socket.SocketChannel} which uses NIO selector based implementation.
*/
public class NioSocketChannel extends AbstractNioByteChannel implements io.netty.channel.socket.SocketChannel {
private static final InternalLogger logger = InternalLoggerFactory.getInstance(NioSocketChannel.class);
private static final SelectorProvider DEFAULT_SELECTOR_PROVIDER = SelectorProvider.provider();
private static SocketChannel newSocket(SelectorProvider provider) {
try {
/**
* Use the {@link SelectorProvider} to open {@link SocketChannel} and so remove condition in
* {@link SelectorProvider#provider()} which is called by each SocketChannel.open() otherwise.
*
* See #2308.
*/
return provider.openSocketChannel();
} catch (IOException e) {
throw new ChannelException("Failed to open a socket.", e);
}
}
private final SocketChannelConfig config;
/**
* Create a new instance
*/
public NioSocketChannel() {
this(DEFAULT_SELECTOR_PROVIDER);
}
/**
* Create a new instance using the given {@link SelectorProvider}.
*/
public NioSocketChannel(SelectorProvider provider) {
this(newSocket(provider));
}
/**
* Create a new instance using the given {@link SocketChannel}.
*/
public NioSocketChannel(SocketChannel socket) {
this(null, socket);
}
/**
* Create a new instance
*
* @param parent the {@link Channel} which created this instance or {@code null} if it was created by the user
* @param socket the {@link SocketChannel} which will be used
*/
public NioSocketChannel(Channel parent, SocketChannel socket) {
super(parent, socket);
config = new NioSocketChannelConfig(this, socket.socket());
}
@Override
public ServerSocketChannel parent() {
return (ServerSocketChannel) super.parent();
}
@Override
public SocketChannelConfig config() {
return config;
}
@Override
protected SocketChannel javaChannel() {
return (SocketChannel) super.javaChannel();
}
@Override
public boolean isActive() {
SocketChannel ch = javaChannel();
return ch.isOpen() && ch.isConnected();
}
@Override
public boolean isOutputShutdown() {
return javaChannel().socket().isOutputShutdown() || !isActive();
}
@Override
public boolean isInputShutdown() {
return javaChannel().socket().isInputShutdown() || !isActive();
}
@Override
public boolean isShutdown() {
Socket socket = javaChannel().socket();
return socket.isInputShutdown() && socket.isOutputShutdown() || !isActive();
}
@Override
public InetSocketAddress localAddress() {
return (InetSocketAddress) super.localAddress();
}
@Override
public InetSocketAddress remoteAddress() {
return (InetSocketAddress) super.remoteAddress();
}
@SuppressJava6Requirement(reason = "Usage guarded by java version check")
@UnstableApi
@Override
protected final void doShutdownOutput() throws Exception {
if (PlatformDependent.javaVersion() >= 7) {
javaChannel().shutdownOutput();
} else {
javaChannel().socket().shutdownOutput();
}
}
@Override
public ChannelFuture shutdownOutput() {
return shutdownOutput(newPromise());
}
@Override
public ChannelFuture shutdownOutput(final ChannelPromise promise) {
final EventLoop loop = eventLoop();
if (loop.inEventLoop()) {
((AbstractUnsafe) unsafe()).shutdownOutput(promise);
} else {
loop.execute(new Runnable() {
@Override
public void run() {
((AbstractUnsafe) unsafe()).shutdownOutput(promise);
}
});
}
return promise;
}
@Override
public ChannelFuture shutdownInput() {
return shutdownInput(newPromise());
}
@Override
protected boolean isInputShutdown0() {
return isInputShutdown();
}
@Override
public ChannelFuture shutdownInput(final ChannelPromise promise) {
EventLoop loop = eventLoop();
if (loop.inEventLoop()) {
shutdownInput0(promise);
} else {
loop.execute(new Runnable() {
@Override
public void run() {
shutdownInput0(promise);
}
});
}
return promise;
}
@Override
public ChannelFuture shutdown() {
return shutdown(newPromise());
}
@Override
public ChannelFuture shutdown(final ChannelPromise promise) {
ChannelFuture shutdownOutputFuture = shutdownOutput();
if (shutdownOutputFuture.isDone()) {
shutdownOutputDone(shutdownOutputFuture, promise);
} else {
shutdownOutputFuture.addListener(new ChannelFutureListener() {
@Override
public void operationComplete(final ChannelFuture shutdownOutputFuture) throws Exception {
shutdownOutputDone(shutdownOutputFuture, promise);
}
});
}
return promise;
}
private void shutdownOutputDone(final ChannelFuture shutdownOutputFuture, final ChannelPromise promise) {
ChannelFuture shutdownInputFuture = shutdownInput();
if (shutdownInputFuture.isDone()) {
shutdownDone(shutdownOutputFuture, shutdownInputFuture, promise);
} else {
shutdownInputFuture.addListener(new ChannelFutureListener() {
@Override
public void operationComplete(ChannelFuture shutdownInputFuture) throws Exception {
shutdownDone(shutdownOutputFuture, shutdownInputFuture, promise);
}
});
}
}
private static void shutdownDone(ChannelFuture shutdownOutputFuture,
ChannelFuture shutdownInputFuture,
ChannelPromise promise) {
Throwable shutdownOutputCause = shutdownOutputFuture.cause();
Throwable shutdownInputCause = shutdownInputFuture.cause();
if (shutdownOutputCause != null) {
if (shutdownInputCause != null) {
logger.debug("Exception suppressed because a previous exception occurred.",
shutdownInputCause);
}
promise.setFailure(shutdownOutputCause);
} else if (shutdownInputCause != null) {
promise.setFailure(shutdownInputCause);
} else {
promise.setSuccess();
}
}
private void shutdownInput0(final ChannelPromise promise) {
try {
shutdownInput0();
promise.setSuccess();
} catch (Throwable t) {
promise.setFailure(t);
}
}
@SuppressJava6Requirement(reason = "Usage guarded by java version check")
private void shutdownInput0() throws Exception {
if (PlatformDependent.javaVersion() >= 7) {
javaChannel().shutdownInput();
} else {
javaChannel().socket().shutdownInput();
}
}
@Override
protected SocketAddress localAddress0() {
return javaChannel().socket().getLocalSocketAddress();
}
@Override
protected SocketAddress remoteAddress0() {
return javaChannel().socket().getRemoteSocketAddress();
}
@Override
protected void doBind(SocketAddress localAddress) throws Exception {
doBind0(localAddress);
}
private void doBind0(SocketAddress localAddress) throws Exception {
if (PlatformDependent.javaVersion() >= 7) {
SocketUtils.bind(javaChannel(), localAddress);
} else {
SocketUtils.bind(javaChannel().socket(), localAddress);
}
}
@Override
protected boolean doConnect(SocketAddress remoteAddress, SocketAddress localAddress) throws Exception {
if (localAddress != null) {
doBind0(localAddress);
}
boolean success = false;
try {
boolean connected = SocketUtils.connect(javaChannel(), remoteAddress);
if (!connected) {
selectionKey().interestOps(SelectionKey.OP_CONNECT);
}
success = true;
return connected;
} finally {
if (!success) {
doClose();
}
}
}
@Override
protected void doFinishConnect() throws Exception {
if (!javaChannel().finishConnect()) {
throw new Error();
}
}
@Override
protected void doDisconnect() throws Exception {
doClose();
}
@Override
protected void doClose() throws Exception {
super.doClose();
javaChannel().close();
}
@Override
protected int doReadBytes(ByteBuf byteBuf) throws Exception {
final RecvByteBufAllocator.Handle allocHandle = unsafe().recvBufAllocHandle();
allocHandle.attemptedBytesRead(byteBuf.writableBytes());
return byteBuf.writeBytes(javaChannel(), allocHandle.attemptedBytesRead());
}
@Override
protected int doWriteBytes(ByteBuf buf) throws Exception {
final int expectedWrittenBytes = buf.readableBytes();
return buf.readBytes(javaChannel(), expectedWrittenBytes);
}
@Override
protected long doWriteFileRegion(FileRegion region) throws Exception {
final long position = region.transferred();
return region.transferTo(javaChannel(), position);
}
private void adjustMaxBytesPerGatheringWrite(int attempted, int written, int oldMaxBytesPerGatheringWrite) {
// By default we track the SO_SNDBUF when ever it is explicitly set. However some OSes may dynamically change
// SO_SNDBUF (and other characteristics that determine how much data can be written at once) so we should try
// make a best effort to adjust as OS behavior changes.
if (attempted == written) {
if (attempted << 1 > oldMaxBytesPerGatheringWrite) {
((NioSocketChannelConfig) config).setMaxBytesPerGatheringWrite(attempted << 1);
}
} else if (attempted > MAX_BYTES_PER_GATHERING_WRITE_ATTEMPTED_LOW_THRESHOLD && written < attempted >>> 1) {
((NioSocketChannelConfig) config).setMaxBytesPerGatheringWrite(attempted >>> 1);
}
}
@Override
protected void doWrite(ChannelOutboundBuffer in) throws Exception {
SocketChannel ch = javaChannel();
int writeSpinCount = config().getWriteSpinCount();
do {
if (in.isEmpty()) {
// All written so clear OP_WRITE
clearOpWrite();
// Directly return here so incompleteWrite(...) is not called.
return;
}
// Ensure the pending writes are made of ByteBufs only.
int maxBytesPerGatheringWrite = ((NioSocketChannelConfig) config).getMaxBytesPerGatheringWrite();
ByteBuffer[] nioBuffers = in.nioBuffers(1024, maxBytesPerGatheringWrite);
int nioBufferCnt = in.nioBufferCount();
// Always us nioBuffers() to workaround data-corruption.
// See https://github.com/netty/netty/issues/2761
switch (nioBufferCnt) {
case 0:
// We have something else beside ByteBuffers to write so fallback to normal writes.
writeSpinCount -= doWrite0(in);
break;
case 1: {
// Only one ByteBuf so use non-gathering write
// Zero length buffers are not added to nioBuffers by ChannelOutboundBuffer, so there is no need
// to check if the total size of all the buffers is non-zero.
ByteBuffer buffer = nioBuffers[0];
int attemptedBytes = buffer.remaining();
final int localWrittenBytes = ch.write(buffer);
if (localWrittenBytes <= 0) {
incompleteWrite(true);
return;
}
adjustMaxBytesPerGatheringWrite(attemptedBytes, localWrittenBytes, maxBytesPerGatheringWrite);
in.removeBytes(localWrittenBytes);
--writeSpinCount;
break;
}
default: {
// Zero length buffers are not added to nioBuffers by ChannelOutboundBuffer, so there is no need
// to check if the total size of all the buffers is non-zero.
// We limit the max amount to int above so cast is safe
long attemptedBytes = in.nioBufferSize();
final long localWrittenBytes = ch.write(nioBuffers, 0, nioBufferCnt);
if (localWrittenBytes <= 0) {
incompleteWrite(true);
return;
}
// Casting to int is safe because we limit the total amount of data in the nioBuffers to int above.
adjustMaxBytesPerGatheringWrite((int) attemptedBytes, (int) localWrittenBytes,
maxBytesPerGatheringWrite);
in.removeBytes(localWrittenBytes);
--writeSpinCount;
break;
}
}
} while (writeSpinCount > 0);
incompleteWrite(writeSpinCount < 0);
}
@Override
protected AbstractNioUnsafe newUnsafe() {
return new NioSocketChannelUnsafe();
}
private final class NioSocketChannelUnsafe extends NioByteUnsafe {
@Override
protected Executor prepareToClose() {
try {
if (javaChannel().isOpen() && config().getSoLinger() > 0) {
// We need to cancel this key of the channel so we may not end up in a eventloop spin
// because we try to read or write until the actual close happens which may be later due
// SO_LINGER handling.
// See https://github.com/netty/netty/issues/4449
doDeregister();
return GlobalEventExecutor.INSTANCE;
}
} catch (Throwable ignore) {
// Ignore the error as the underlying channel may be closed in the meantime and so
// getSoLinger() may produce an exception. In this case we just return null.
// See https://github.com/netty/netty/issues/4449
}
return null;
}
}
private final class NioSocketChannelConfig extends DefaultSocketChannelConfig {
private volatile int maxBytesPerGatheringWrite = Integer.MAX_VALUE;
private NioSocketChannelConfig(NioSocketChannel channel, Socket javaSocket) {
super(channel, javaSocket);
calculateMaxBytesPerGatheringWrite();
}
@Override
protected void autoReadCleared() {
clearReadPending();
}
@Override
public NioSocketChannelConfig setSendBufferSize(int sendBufferSize) {
super.setSendBufferSize(sendBufferSize);
calculateMaxBytesPerGatheringWrite();
return this;
}
@Override
public boolean setOption(ChannelOption option, T value) {
if (PlatformDependent.javaVersion() >= 7 && option instanceof NioChannelOption) {
return NioChannelOption.setOption(jdkChannel(), (NioChannelOption) option, value);
}
return super.setOption(option, value);
}
@Override
public T getOption(ChannelOption option) {
if (PlatformDependent.javaVersion() >= 7 && option instanceof NioChannelOption) {
return NioChannelOption.getOption(jdkChannel(), (NioChannelOption) option);
}
return super.getOption(option);
}
@Override
public Map, Object> getOptions() {
if (PlatformDependent.javaVersion() >= 7) {
return getOptions(super.getOptions(), NioChannelOption.getOptions(jdkChannel()));
}
return super.getOptions();
}
void setMaxBytesPerGatheringWrite(int maxBytesPerGatheringWrite) {
this.maxBytesPerGatheringWrite = maxBytesPerGatheringWrite;
}
int getMaxBytesPerGatheringWrite() {
return maxBytesPerGatheringWrite;
}
private void calculateMaxBytesPerGatheringWrite() {
// Multiply by 2 to give some extra space in case the OS can process write data faster than we can provide.
int newSendBufferSize = getSendBufferSize() << 1;
if (newSendBufferSize > 0) {
setMaxBytesPerGatheringWrite(newSendBufferSize);
}
}
private SocketChannel jdkChannel() {
return ((NioSocketChannel) channel).javaChannel();
}
}
}