io.netty.channel.epoll.AbstractEpollChannel Maven / Gradle / Ivy
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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including
all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and
JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
/*
* Copyright 2014 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:
*
* https://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.epoll;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufAllocator;
import io.netty.buffer.ByteBufUtil;
import io.netty.buffer.Unpooled;
import io.netty.channel.AbstractChannel;
import io.netty.channel.Channel;
import io.netty.channel.ChannelConfig;
import io.netty.channel.ChannelException;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelMetadata;
import io.netty.channel.ChannelOutboundBuffer;
import io.netty.channel.ChannelPromise;
import io.netty.channel.ConnectTimeoutException;
import io.netty.channel.EventLoop;
import io.netty.channel.RecvByteBufAllocator;
import io.netty.channel.socket.ChannelInputShutdownEvent;
import io.netty.channel.socket.ChannelInputShutdownReadComplete;
import io.netty.channel.socket.SocketChannelConfig;
import io.netty.channel.unix.FileDescriptor;
import io.netty.channel.unix.IovArray;
import io.netty.channel.unix.Socket;
import io.netty.channel.unix.UnixChannel;
import io.netty.util.ReferenceCountUtil;
import io.netty.util.concurrent.Future;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.net.SocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.AlreadyConnectedException;
import java.nio.channels.ClosedChannelException;
import java.nio.channels.ConnectionPendingException;
import java.nio.channels.NotYetConnectedException;
import java.nio.channels.UnresolvedAddressException;
import java.util.concurrent.TimeUnit;
import static io.netty.channel.internal.ChannelUtils.WRITE_STATUS_SNDBUF_FULL;
import static io.netty.channel.unix.UnixChannelUtil.computeRemoteAddr;
import static io.netty.util.internal.ObjectUtil.checkNotNull;
abstract class AbstractEpollChannel extends AbstractChannel implements UnixChannel {
private static final ChannelMetadata METADATA = new ChannelMetadata(false);
final LinuxSocket socket;
/**
* The future of the current connection attempt. If not null, subsequent
* connection attempts will fail.
*/
private ChannelPromise connectPromise;
private Future connectTimeoutFuture;
private SocketAddress requestedRemoteAddress;
private volatile SocketAddress local;
private volatile SocketAddress remote;
protected int flags = Native.EPOLLET;
boolean inputClosedSeenErrorOnRead;
boolean epollInReadyRunnablePending;
protected volatile boolean active;
AbstractEpollChannel(LinuxSocket fd) {
this(null, fd, false);
}
AbstractEpollChannel(Channel parent, LinuxSocket fd, boolean active) {
super(parent);
this.socket = checkNotNull(fd, "fd");
this.active = active;
if (active) {
// Directly cache the remote and local addresses
// See https://github.com/netty/netty/issues/2359
this.local = fd.localAddress();
this.remote = fd.remoteAddress();
}
}
AbstractEpollChannel(Channel parent, LinuxSocket fd, SocketAddress remote) {
super(parent);
this.socket = checkNotNull(fd, "fd");
this.active = true;
// Directly cache the remote and local addresses
// See https://github.com/netty/netty/issues/2359
this.remote = remote;
this.local = fd.localAddress();
}
static boolean isSoErrorZero(Socket fd) {
try {
return fd.getSoError() == 0;
} catch (IOException e) {
throw new ChannelException(e);
}
}
void setFlag(int flag) throws IOException {
if (!isFlagSet(flag)) {
flags |= flag;
modifyEvents();
}
}
void clearFlag(int flag) throws IOException {
if (isFlagSet(flag)) {
flags &= ~flag;
modifyEvents();
}
}
boolean isFlagSet(int flag) {
return (flags & flag) != 0;
}
@Override
public final FileDescriptor fd() {
return socket;
}
@Override
public abstract EpollChannelConfig config();
@Override
public boolean isActive() {
return active;
}
@Override
public ChannelMetadata metadata() {
return METADATA;
}
@Override
protected void doClose() throws Exception {
active = false;
// Even if we allow half closed sockets we should give up on reading. Otherwise we may allow a read attempt on a
// socket which has not even been connected yet. This has been observed to block during unit tests.
inputClosedSeenErrorOnRead = true;
try {
ChannelPromise promise = connectPromise;
if (promise != null) {
// Use tryFailure() instead of setFailure() to avoid the race against cancel().
promise.tryFailure(new ClosedChannelException());
connectPromise = null;
}
Future future = connectTimeoutFuture;
if (future != null) {
future.cancel(false);
connectTimeoutFuture = null;
}
if (isRegistered()) {
// Need to check if we are on the EventLoop as doClose() may be triggered by the GlobalEventExecutor
// if SO_LINGER is used.
//
// See https://github.com/netty/netty/issues/7159
EventLoop loop = eventLoop();
if (loop.inEventLoop()) {
doDeregister();
} else {
loop.execute(new Runnable() {
@Override
public void run() {
try {
doDeregister();
} catch (Throwable cause) {
pipeline().fireExceptionCaught(cause);
}
}
});
}
}
} finally {
socket.close();
}
}
void resetCachedAddresses() {
local = socket.localAddress();
remote = socket.remoteAddress();
}
@Override
protected void doDisconnect() throws Exception {
doClose();
}
@Override
protected boolean isCompatible(EventLoop loop) {
return loop instanceof EpollEventLoop;
}
@Override
public boolean isOpen() {
return socket.isOpen();
}
@Override
protected void doDeregister() throws Exception {
((EpollEventLoop) eventLoop()).remove(this);
}
@Override
protected final void doBeginRead() throws Exception {
// Channel.read() or ChannelHandlerContext.read() was called
final AbstractEpollUnsafe unsafe = (AbstractEpollUnsafe) unsafe();
unsafe.readPending = true;
// We must set the read flag here as it is possible the user didn't read in the last read loop, the
// executeEpollInReadyRunnable could read nothing, and if the user doesn't explicitly call read they will
// never get data after this.
setFlag(Native.EPOLLIN);
// If EPOLL ET mode is enabled and auto read was toggled off on the last read loop then we may not be notified
// again if we didn't consume all the data. So we force a read operation here if there maybe more data.
if (unsafe.maybeMoreDataToRead) {
unsafe.executeEpollInReadyRunnable(config());
}
}
final boolean shouldBreakEpollInReady(ChannelConfig config) {
return socket.isInputShutdown() && (inputClosedSeenErrorOnRead || !isAllowHalfClosure(config));
}
private static boolean isAllowHalfClosure(ChannelConfig config) {
if (config instanceof EpollDomainSocketChannelConfig) {
return ((EpollDomainSocketChannelConfig) config).isAllowHalfClosure();
}
return config instanceof SocketChannelConfig &&
((SocketChannelConfig) config).isAllowHalfClosure();
}
final void clearEpollIn() {
// Only clear if registered with an EventLoop as otherwise
if (isRegistered()) {
final EventLoop loop = eventLoop();
final AbstractEpollUnsafe unsafe = (AbstractEpollUnsafe) unsafe();
if (loop.inEventLoop()) {
unsafe.clearEpollIn0();
} else {
// schedule a task to clear the EPOLLIN as it is not safe to modify it directly
loop.execute(new Runnable() {
@Override
public void run() {
if (!unsafe.readPending && !config().isAutoRead()) {
// Still no read triggered so clear it now
unsafe.clearEpollIn0();
}
}
});
}
} else {
// The EventLoop is not registered atm so just update the flags so the correct value
// will be used once the channel is registered
flags &= ~Native.EPOLLIN;
}
}
private void modifyEvents() throws IOException {
if (isOpen() && isRegistered()) {
((EpollEventLoop) eventLoop()).modify(this);
}
}
@Override
protected void doRegister() throws Exception {
// Just in case the previous EventLoop was shutdown abruptly, or an event is still pending on the old EventLoop
// make sure the epollInReadyRunnablePending variable is reset so we will be able to execute the Runnable on the
// new EventLoop.
epollInReadyRunnablePending = false;
((EpollEventLoop) eventLoop()).add(this);
}
@Override
protected abstract AbstractEpollUnsafe newUnsafe();
/**
* Returns an off-heap copy of the specified {@link ByteBuf}, and releases the original one.
*/
protected final ByteBuf newDirectBuffer(ByteBuf buf) {
return newDirectBuffer(buf, buf);
}
/**
* Returns an off-heap copy of the specified {@link ByteBuf}, and releases the specified holder.
* The caller must ensure that the holder releases the original {@link ByteBuf} when the holder is released by
* this method.
*/
protected final ByteBuf newDirectBuffer(Object holder, ByteBuf buf) {
final int readableBytes = buf.readableBytes();
if (readableBytes == 0) {
ReferenceCountUtil.release(holder);
return Unpooled.EMPTY_BUFFER;
}
final ByteBufAllocator alloc = alloc();
if (alloc.isDirectBufferPooled()) {
return newDirectBuffer0(holder, buf, alloc, readableBytes);
}
final ByteBuf directBuf = ByteBufUtil.threadLocalDirectBuffer();
if (directBuf == null) {
return newDirectBuffer0(holder, buf, alloc, readableBytes);
}
directBuf.writeBytes(buf, buf.readerIndex(), readableBytes);
ReferenceCountUtil.safeRelease(holder);
return directBuf;
}
private static ByteBuf newDirectBuffer0(Object holder, ByteBuf buf, ByteBufAllocator alloc, int capacity) {
final ByteBuf directBuf = alloc.directBuffer(capacity);
directBuf.writeBytes(buf, buf.readerIndex(), capacity);
ReferenceCountUtil.safeRelease(holder);
return directBuf;
}
protected static void checkResolvable(InetSocketAddress addr) {
if (addr.isUnresolved()) {
throw new UnresolvedAddressException();
}
}
/**
* Read bytes into the given {@link ByteBuf} and return the amount.
*/
protected final int doReadBytes(ByteBuf byteBuf) throws Exception {
int writerIndex = byteBuf.writerIndex();
int localReadAmount;
unsafe().recvBufAllocHandle().attemptedBytesRead(byteBuf.writableBytes());
if (byteBuf.hasMemoryAddress()) {
localReadAmount = socket.recvAddress(byteBuf.memoryAddress(), writerIndex, byteBuf.capacity());
} else {
ByteBuffer buf = byteBuf.internalNioBuffer(writerIndex, byteBuf.writableBytes());
localReadAmount = socket.recv(buf, buf.position(), buf.limit());
}
if (localReadAmount > 0) {
byteBuf.writerIndex(writerIndex + localReadAmount);
}
return localReadAmount;
}
protected final int doWriteBytes(ChannelOutboundBuffer in, ByteBuf buf) throws Exception {
if (buf.hasMemoryAddress()) {
int localFlushedAmount = socket.sendAddress(buf.memoryAddress(), buf.readerIndex(), buf.writerIndex());
if (localFlushedAmount > 0) {
in.removeBytes(localFlushedAmount);
return 1;
}
} else {
final ByteBuffer nioBuf = buf.nioBufferCount() == 1 ?
buf.internalNioBuffer(buf.readerIndex(), buf.readableBytes()) : buf.nioBuffer();
int localFlushedAmount = socket.send(nioBuf, nioBuf.position(), nioBuf.limit());
if (localFlushedAmount > 0) {
nioBuf.position(nioBuf.position() + localFlushedAmount);
in.removeBytes(localFlushedAmount);
return 1;
}
}
return WRITE_STATUS_SNDBUF_FULL;
}
/**
* Write bytes to the socket, with or without a remote address.
* Used for datagram and TCP client fast open writes.
*/
final long doWriteOrSendBytes(ByteBuf data, InetSocketAddress remoteAddress, boolean fastOpen)
throws IOException {
assert !(fastOpen && remoteAddress == null) : "fastOpen requires a remote address";
if (data.hasMemoryAddress()) {
long memoryAddress = data.memoryAddress();
if (remoteAddress == null) {
return socket.sendAddress(memoryAddress, data.readerIndex(), data.writerIndex());
}
return socket.sendToAddress(memoryAddress, data.readerIndex(), data.writerIndex(),
remoteAddress.getAddress(), remoteAddress.getPort(), fastOpen);
}
if (data.nioBufferCount() > 1) {
IovArray array = ((EpollEventLoop) eventLoop()).cleanIovArray();
array.add(data, data.readerIndex(), data.readableBytes());
int cnt = array.count();
assert cnt != 0;
if (remoteAddress == null) {
return socket.writevAddresses(array.memoryAddress(0), cnt);
}
return socket.sendToAddresses(array.memoryAddress(0), cnt,
remoteAddress.getAddress(), remoteAddress.getPort(), fastOpen);
}
ByteBuffer nioData = data.internalNioBuffer(data.readerIndex(), data.readableBytes());
if (remoteAddress == null) {
return socket.send(nioData, nioData.position(), nioData.limit());
}
return socket.sendTo(nioData, nioData.position(), nioData.limit(),
remoteAddress.getAddress(), remoteAddress.getPort(), fastOpen);
}
protected abstract class AbstractEpollUnsafe extends AbstractUnsafe {
boolean readPending;
boolean maybeMoreDataToRead;
private EpollRecvByteAllocatorHandle allocHandle;
private final Runnable epollInReadyRunnable = new Runnable() {
@Override
public void run() {
epollInReadyRunnablePending = false;
epollInReady();
}
};
/**
* Called once EPOLLIN event is ready to be processed
*/
abstract void epollInReady();
final void epollInBefore() {
maybeMoreDataToRead = false;
}
final void epollInFinally(ChannelConfig config) {
maybeMoreDataToRead = allocHandle.maybeMoreDataToRead();
if (allocHandle.isReceivedRdHup() || (readPending && maybeMoreDataToRead)) {
// trigger a read again as there may be something left to read and because of epoll ET we
// will not get notified again until we read everything from the socket
//
// It is possible the last fireChannelRead call could cause the user to call read() again, or if
// autoRead is true the call to channelReadComplete would also call read, but maybeMoreDataToRead is set
// to false before every read operation to prevent re-entry into epollInReady() we will not read from
// the underlying OS again unless the user happens to call read again.
executeEpollInReadyRunnable(config);
} else if (!readPending && !config.isAutoRead()) {
// Check if there is a readPending which was not processed yet.
// This could be for two reasons:
// * The user called Channel.read() or ChannelHandlerContext.read() in channelRead(...) method
// * The user called Channel.read() or ChannelHandlerContext.read() in channelReadComplete(...) method
//
// See https://github.com/netty/netty/issues/2254
clearEpollIn();
}
}
final void executeEpollInReadyRunnable(ChannelConfig config) {
if (epollInReadyRunnablePending || !isActive() || shouldBreakEpollInReady(config)) {
return;
}
epollInReadyRunnablePending = true;
eventLoop().execute(epollInReadyRunnable);
}
/**
* Called once EPOLLRDHUP event is ready to be processed
*/
final void epollRdHupReady() {
// This must happen before we attempt to read. This will ensure reading continues until an error occurs.
recvBufAllocHandle().receivedRdHup();
if (isActive()) {
// If it is still active, we need to call epollInReady as otherwise we may miss to
// read pending data from the underlying file descriptor.
// See https://github.com/netty/netty/issues/3709
epollInReady();
} else {
// Just to be safe make sure the input marked as closed.
shutdownInput(true);
}
// Clear the EPOLLRDHUP flag to prevent continuously getting woken up on this event.
clearEpollRdHup();
}
/**
* Clear the {@link Native#EPOLLRDHUP} flag from EPOLL, and close on failure.
*/
private void clearEpollRdHup() {
try {
clearFlag(Native.EPOLLRDHUP);
} catch (IOException e) {
pipeline().fireExceptionCaught(e);
close(voidPromise());
}
}
/**
* Shutdown the input side of the channel.
*/
void shutdownInput(boolean rdHup) {
if (!socket.isInputShutdown()) {
if (isAllowHalfClosure(config())) {
try {
socket.shutdown(true, false);
} catch (IOException ignored) {
// We attempted to shutdown and failed, which means the input has already effectively been
// shutdown.
fireEventAndClose(ChannelInputShutdownEvent.INSTANCE);
return;
} catch (NotYetConnectedException ignore) {
// We attempted to shutdown and failed, which means the input has already effectively been
// shutdown.
}
clearEpollIn0();
pipeline().fireUserEventTriggered(ChannelInputShutdownEvent.INSTANCE);
} else {
close(voidPromise());
}
} else if (!rdHup && !inputClosedSeenErrorOnRead) {
inputClosedSeenErrorOnRead = true;
pipeline().fireUserEventTriggered(ChannelInputShutdownReadComplete.INSTANCE);
}
}
private void fireEventAndClose(Object evt) {
pipeline().fireUserEventTriggered(evt);
close(voidPromise());
}
@Override
public EpollRecvByteAllocatorHandle recvBufAllocHandle() {
if (allocHandle == null) {
allocHandle = newEpollHandle((RecvByteBufAllocator.ExtendedHandle) super.recvBufAllocHandle());
}
return allocHandle;
}
/**
* Create a new {@link EpollRecvByteAllocatorHandle} instance.
* @param handle The handle to wrap with EPOLL specific logic.
*/
EpollRecvByteAllocatorHandle newEpollHandle(RecvByteBufAllocator.ExtendedHandle handle) {
return new EpollRecvByteAllocatorHandle(handle);
}
@Override
protected final void flush0() {
// Flush immediately only when there's no pending flush.
// If there's a pending flush operation, event loop will call forceFlush() later,
// and thus there's no need to call it now.
if (!isFlagSet(Native.EPOLLOUT)) {
super.flush0();
}
}
/**
* Called once a EPOLLOUT event is ready to be processed
*/
final void epollOutReady() {
if (connectPromise != null) {
// pending connect which is now complete so handle it.
finishConnect();
} else if (!socket.isOutputShutdown()) {
// directly call super.flush0() to force a flush now
super.flush0();
}
}
protected final void clearEpollIn0() {
assert eventLoop().inEventLoop();
try {
readPending = false;
clearFlag(Native.EPOLLIN);
} catch (IOException e) {
// When this happens there is something completely wrong with either the filedescriptor or epoll,
// so fire the exception through the pipeline and close the Channel.
pipeline().fireExceptionCaught(e);
unsafe().close(unsafe().voidPromise());
}
}
@Override
public void connect(
final SocketAddress remoteAddress, final SocketAddress localAddress, final ChannelPromise promise) {
if (!promise.setUncancellable() || !ensureOpen(promise)) {
return;
}
try {
if (connectPromise != null) {
throw new ConnectionPendingException();
}
boolean wasActive = isActive();
if (doConnect(remoteAddress, localAddress)) {
fulfillConnectPromise(promise, wasActive);
} else {
connectPromise = promise;
requestedRemoteAddress = remoteAddress;
// Schedule connect timeout.
int connectTimeoutMillis = config().getConnectTimeoutMillis();
if (connectTimeoutMillis > 0) {
connectTimeoutFuture = eventLoop().schedule(new Runnable() {
@Override
public void run() {
ChannelPromise connectPromise = AbstractEpollChannel.this.connectPromise;
if (connectPromise != null && !connectPromise.isDone()
&& connectPromise.tryFailure(new ConnectTimeoutException(
"connection timed out: " + remoteAddress))) {
close(voidPromise());
}
}
}, connectTimeoutMillis, TimeUnit.MILLISECONDS);
}
promise.addListener(new ChannelFutureListener() {
@Override
public void operationComplete(ChannelFuture future) throws Exception {
if (future.isCancelled()) {
if (connectTimeoutFuture != null) {
connectTimeoutFuture.cancel(false);
}
connectPromise = null;
close(voidPromise());
}
}
});
}
} catch (Throwable t) {
closeIfClosed();
promise.tryFailure(annotateConnectException(t, remoteAddress));
}
}
private void fulfillConnectPromise(ChannelPromise promise, boolean wasActive) {
if (promise == null) {
// Closed via cancellation and the promise has been notified already.
return;
}
active = true;
// Get the state as trySuccess() may trigger an ChannelFutureListener that will close the Channel.
// We still need to ensure we call fireChannelActive() in this case.
boolean active = isActive();
// trySuccess() will return false if a user cancelled the connection attempt.
boolean promiseSet = promise.trySuccess();
// Regardless if the connection attempt was cancelled, channelActive() event should be triggered,
// because what happened is what happened.
if (!wasActive && active) {
pipeline().fireChannelActive();
}
// If a user cancelled the connection attempt, close the channel, which is followed by channelInactive().
if (!promiseSet) {
close(voidPromise());
}
}
private void fulfillConnectPromise(ChannelPromise promise, Throwable cause) {
if (promise == null) {
// Closed via cancellation and the promise has been notified already.
return;
}
// Use tryFailure() instead of setFailure() to avoid the race against cancel().
promise.tryFailure(cause);
closeIfClosed();
}
private void finishConnect() {
// Note this method is invoked by the event loop only if the connection attempt was
// neither cancelled nor timed out.
assert eventLoop().inEventLoop();
boolean connectStillInProgress = false;
try {
boolean wasActive = isActive();
if (!doFinishConnect()) {
connectStillInProgress = true;
return;
}
fulfillConnectPromise(connectPromise, wasActive);
} catch (Throwable t) {
fulfillConnectPromise(connectPromise, annotateConnectException(t, requestedRemoteAddress));
} finally {
if (!connectStillInProgress) {
// Check for null as the connectTimeoutFuture is only created if a connectTimeoutMillis > 0 is used
// See https://github.com/netty/netty/issues/1770
if (connectTimeoutFuture != null) {
connectTimeoutFuture.cancel(false);
}
connectPromise = null;
}
}
}
/**
* Finish the connect
*/
private boolean doFinishConnect() throws Exception {
if (socket.finishConnect()) {
clearFlag(Native.EPOLLOUT);
if (requestedRemoteAddress instanceof InetSocketAddress) {
remote = computeRemoteAddr((InetSocketAddress) requestedRemoteAddress, socket.remoteAddress());
}
requestedRemoteAddress = null;
return true;
}
setFlag(Native.EPOLLOUT);
return false;
}
}
@Override
protected void doBind(SocketAddress local) throws Exception {
if (local instanceof InetSocketAddress) {
checkResolvable((InetSocketAddress) local);
}
socket.bind(local);
this.local = socket.localAddress();
}
/**
* Connect to the remote peer
*/
protected boolean doConnect(SocketAddress remoteAddress, SocketAddress localAddress) throws Exception {
if (localAddress instanceof InetSocketAddress) {
checkResolvable((InetSocketAddress) localAddress);
}
InetSocketAddress remoteSocketAddr = remoteAddress instanceof InetSocketAddress
? (InetSocketAddress) remoteAddress : null;
if (remoteSocketAddr != null) {
checkResolvable(remoteSocketAddr);
}
if (remote != null) {
// Check if already connected before trying to connect. This is needed as connect(...) will not return -1
// and set errno to EISCONN if a previous connect(...) attempt was setting errno to EINPROGRESS and finished
// later.
throw new AlreadyConnectedException();
}
if (localAddress != null) {
socket.bind(localAddress);
}
boolean connected = doConnect0(remoteAddress);
if (connected) {
remote = remoteSocketAddr == null ?
remoteAddress : computeRemoteAddr(remoteSocketAddr, socket.remoteAddress());
}
// We always need to set the localAddress even if not connected yet as the bind already took place.
//
// See https://github.com/netty/netty/issues/3463
local = socket.localAddress();
return connected;
}
boolean doConnect0(SocketAddress remote) throws Exception {
boolean success = false;
try {
boolean connected = socket.connect(remote);
if (!connected) {
setFlag(Native.EPOLLOUT);
}
success = true;
return connected;
} finally {
if (!success) {
doClose();
}
}
}
@Override
protected SocketAddress localAddress0() {
return local;
}
@Override
protected SocketAddress remoteAddress0() {
return remote;
}
}