io.netty.channel.epoll.AbstractEpollStreamChannel Maven / Gradle / Ivy
Go to download
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 2015 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.channel.Channel;
import io.netty.channel.ChannelConfig;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelMetadata;
import io.netty.channel.ChannelOutboundBuffer;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.ChannelPromise;
import io.netty.channel.DefaultFileRegion;
import io.netty.channel.EventLoop;
import io.netty.channel.FileRegion;
import io.netty.channel.RecvByteBufAllocator;
import io.netty.channel.internal.ChannelUtils;
import io.netty.channel.socket.DuplexChannel;
import io.netty.channel.unix.FileDescriptor;
import io.netty.channel.unix.IovArray;
import io.netty.channel.unix.SocketWritableByteChannel;
import io.netty.channel.unix.UnixChannelUtil;
import io.netty.util.internal.PlatformDependent;
import io.netty.util.internal.StringUtil;
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.SocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.ClosedChannelException;
import java.nio.channels.WritableByteChannel;
import java.util.Queue;
import java.util.concurrent.Executor;
import static io.netty.channel.internal.ChannelUtils.MAX_BYTES_PER_GATHERING_WRITE_ATTEMPTED_LOW_THRESHOLD;
import static io.netty.channel.internal.ChannelUtils.WRITE_STATUS_SNDBUF_FULL;
import static io.netty.channel.unix.FileDescriptor.pipe;
import static io.netty.util.internal.ObjectUtil.checkNotNull;
import static io.netty.util.internal.ObjectUtil.checkPositiveOrZero;
public abstract class AbstractEpollStreamChannel extends AbstractEpollChannel implements DuplexChannel {
private static final ChannelMetadata METADATA = new ChannelMetadata(false, 16);
private static final String EXPECTED_TYPES =
" (expected: " + StringUtil.simpleClassName(ByteBuf.class) + ", " +
StringUtil.simpleClassName(DefaultFileRegion.class) + ')';
private static final InternalLogger logger = InternalLoggerFactory.getInstance(AbstractEpollStreamChannel.class);
private final Runnable flushTask = new Runnable() {
@Override
public void run() {
// Calling flush0 directly to ensure we not try to flush messages that were added via write(...) in the
// meantime.
((AbstractEpollUnsafe) unsafe()).flush0();
}
};
// Lazy init these if we need to splice(...)
private volatile Queue spliceQueue;
private FileDescriptor pipeIn;
private FileDescriptor pipeOut;
private WritableByteChannel byteChannel;
protected AbstractEpollStreamChannel(Channel parent, int fd) {
this(parent, new LinuxSocket(fd));
}
protected AbstractEpollStreamChannel(int fd) {
this(new LinuxSocket(fd));
}
AbstractEpollStreamChannel(LinuxSocket fd) {
this(fd, isSoErrorZero(fd));
}
AbstractEpollStreamChannel(Channel parent, LinuxSocket fd) {
super(parent, fd, true);
// Add EPOLLRDHUP so we are notified once the remote peer close the connection.
flags |= Native.EPOLLRDHUP;
}
AbstractEpollStreamChannel(Channel parent, LinuxSocket fd, SocketAddress remote) {
super(parent, fd, remote);
// Add EPOLLRDHUP so we are notified once the remote peer close the connection.
flags |= Native.EPOLLRDHUP;
}
protected AbstractEpollStreamChannel(LinuxSocket fd, boolean active) {
super(null, fd, active);
// Add EPOLLRDHUP so we are notified once the remote peer close the connection.
flags |= Native.EPOLLRDHUP;
}
@Override
protected AbstractEpollUnsafe newUnsafe() {
return new EpollStreamUnsafe();
}
@Override
public ChannelMetadata metadata() {
return METADATA;
}
/**
* Splice from this {@link AbstractEpollStreamChannel} to another {@link AbstractEpollStreamChannel}.
* The {@code len} is the number of bytes to splice. If using {@link Integer#MAX_VALUE} it will
* splice until the {@link ChannelFuture} was canceled or it was failed.
*
* Please note:
*
* - both channels need to be registered to the same {@link EventLoop}, otherwise an
* {@link IllegalArgumentException} is thrown.
* - {@link EpollChannelConfig#getEpollMode()} must be {@link EpollMode#LEVEL_TRIGGERED} for this and the
* target {@link AbstractEpollStreamChannel}
*
*
*/
public final ChannelFuture spliceTo(final AbstractEpollStreamChannel ch, final int len) {
return spliceTo(ch, len, newPromise());
}
/**
* Splice from this {@link AbstractEpollStreamChannel} to another {@link AbstractEpollStreamChannel}.
* The {@code len} is the number of bytes to splice. If using {@link Integer#MAX_VALUE} it will
* splice until the {@link ChannelFuture} was canceled or it was failed.
*
* Please note:
*
* - both channels need to be registered to the same {@link EventLoop}, otherwise an
* {@link IllegalArgumentException} is thrown.
* - {@link EpollChannelConfig#getEpollMode()} must be {@link EpollMode#LEVEL_TRIGGERED} for this and the
* target {@link AbstractEpollStreamChannel}
*
*
*/
public final ChannelFuture spliceTo(final AbstractEpollStreamChannel ch, final int len,
final ChannelPromise promise) {
if (ch.eventLoop() != eventLoop()) {
throw new IllegalArgumentException("EventLoops are not the same.");
}
checkPositiveOrZero(len, "len");
if (ch.config().getEpollMode() != EpollMode.LEVEL_TRIGGERED
|| config().getEpollMode() != EpollMode.LEVEL_TRIGGERED) {
throw new IllegalStateException("spliceTo() supported only when using " + EpollMode.LEVEL_TRIGGERED);
}
checkNotNull(promise, "promise");
if (!isOpen()) {
promise.tryFailure(new ClosedChannelException());
} else {
addToSpliceQueue(new SpliceInChannelTask(ch, len, promise));
failSpliceIfClosed(promise);
}
return promise;
}
/**
* Splice from this {@link AbstractEpollStreamChannel} to another {@link FileDescriptor}.
* The {@code offset} is the offset for the {@link FileDescriptor} and {@code len} is the
* number of bytes to splice. If using {@link Integer#MAX_VALUE} it will splice until the
* {@link ChannelFuture} was canceled or it was failed.
*
* Please note:
*
* - {@link EpollChannelConfig#getEpollMode()} must be {@link EpollMode#LEVEL_TRIGGERED} for this
* {@link AbstractEpollStreamChannel}
* - the {@link FileDescriptor} will not be closed after the {@link ChannelFuture} is notified
* - this channel must be registered to an event loop or {@link IllegalStateException} will be thrown.
*
*/
public final ChannelFuture spliceTo(final FileDescriptor ch, final int offset, final int len) {
return spliceTo(ch, offset, len, newPromise());
}
/**
* Splice from this {@link AbstractEpollStreamChannel} to another {@link FileDescriptor}.
* The {@code offset} is the offset for the {@link FileDescriptor} and {@code len} is the
* number of bytes to splice. If using {@link Integer#MAX_VALUE} it will splice until the
* {@link ChannelFuture} was canceled or it was failed.
*
* Please note:
*
* - {@link EpollChannelConfig#getEpollMode()} must be {@link EpollMode#LEVEL_TRIGGERED} for this
* {@link AbstractEpollStreamChannel}
* - the {@link FileDescriptor} will not be closed after the {@link ChannelPromise} is notified
* - this channel must be registered to an event loop or {@link IllegalStateException} will be thrown.
*
*/
public final ChannelFuture spliceTo(final FileDescriptor ch, final int offset, final int len,
final ChannelPromise promise) {
checkPositiveOrZero(len, "len");
checkPositiveOrZero(offset, "offset");
if (config().getEpollMode() != EpollMode.LEVEL_TRIGGERED) {
throw new IllegalStateException("spliceTo() supported only when using " + EpollMode.LEVEL_TRIGGERED);
}
checkNotNull(promise, "promise");
if (!isOpen()) {
promise.tryFailure(new ClosedChannelException());
} else {
addToSpliceQueue(new SpliceFdTask(ch, offset, len, promise));
failSpliceIfClosed(promise);
}
return promise;
}
private void failSpliceIfClosed(ChannelPromise promise) {
if (!isOpen()) {
// Seems like the Channel was closed in the meantime try to fail the promise to prevent any
// cases where a future may not be notified otherwise.
if (promise.tryFailure(new ClosedChannelException())) {
eventLoop().execute(new Runnable() {
@Override
public void run() {
// Call this via the EventLoop as it is a MPSC queue.
clearSpliceQueue();
}
});
}
}
}
/**
* Write bytes form the given {@link ByteBuf} to the underlying {@link java.nio.channels.Channel}.
* @param in the collection which contains objects to write.
* @param buf the {@link ByteBuf} from which the bytes should be written
* @return The value that should be decremented from the write quantum which starts at
* {@link ChannelConfig#getWriteSpinCount()}. The typical use cases are as follows:
*
* - 0 - if no write was attempted. This is appropriate if an empty {@link ByteBuf} (or other empty content)
* is encountered
* - 1 - if a single call to write data was made to the OS
* - {@link ChannelUtils#WRITE_STATUS_SNDBUF_FULL} - if an attempt to write data was made to the OS, but
* no data was accepted
*
*/
private int writeBytes(ChannelOutboundBuffer in, ByteBuf buf) throws Exception {
int readableBytes = buf.readableBytes();
if (readableBytes == 0) {
in.remove();
return 0;
}
if (buf.hasMemoryAddress() || buf.nioBufferCount() == 1) {
return doWriteBytes(in, buf);
} else {
ByteBuffer[] nioBuffers = buf.nioBuffers();
return writeBytesMultiple(in, nioBuffers, nioBuffers.length, readableBytes,
config().getMaxBytesPerGatheringWrite());
}
}
private void adjustMaxBytesPerGatheringWrite(long attempted, long written, long 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) {
config().setMaxBytesPerGatheringWrite(attempted << 1);
}
} else if (attempted > MAX_BYTES_PER_GATHERING_WRITE_ATTEMPTED_LOW_THRESHOLD && written < attempted >>> 1) {
config().setMaxBytesPerGatheringWrite(attempted >>> 1);
}
}
/**
* Write multiple bytes via {@link IovArray}.
* @param in the collection which contains objects to write.
* @param array The array which contains the content to write.
* @return The value that should be decremented from the write quantum which starts at
* {@link ChannelConfig#getWriteSpinCount()}. The typical use cases are as follows:
*
* - 0 - if no write was attempted. This is appropriate if an empty {@link ByteBuf} (or other empty content)
* is encountered
* - 1 - if a single call to write data was made to the OS
* - {@link ChannelUtils#WRITE_STATUS_SNDBUF_FULL} - if an attempt to write data was made to the OS, but
* no data was accepted
*
* @throws IOException If an I/O exception occurs during write.
*/
private int writeBytesMultiple(ChannelOutboundBuffer in, IovArray array) throws IOException {
final long expectedWrittenBytes = array.size();
assert expectedWrittenBytes != 0;
final int cnt = array.count();
assert cnt != 0;
final long localWrittenBytes = socket.writevAddresses(array.memoryAddress(0), cnt);
if (localWrittenBytes > 0) {
adjustMaxBytesPerGatheringWrite(expectedWrittenBytes, localWrittenBytes, array.maxBytes());
in.removeBytes(localWrittenBytes);
return 1;
}
return WRITE_STATUS_SNDBUF_FULL;
}
/**
* Write multiple bytes via {@link ByteBuffer} array.
* @param in the collection which contains objects to write.
* @param nioBuffers The buffers to write.
* @param nioBufferCnt The number of buffers to write.
* @param expectedWrittenBytes The number of bytes we expect to write.
* @param maxBytesPerGatheringWrite The maximum number of bytes we should attempt to write.
* @return The value that should be decremented from the write quantum which starts at
* {@link ChannelConfig#getWriteSpinCount()}. The typical use cases are as follows:
*
* - 0 - if no write was attempted. This is appropriate if an empty {@link ByteBuf} (or other empty content)
* is encountered
* - 1 - if a single call to write data was made to the OS
* - {@link ChannelUtils#WRITE_STATUS_SNDBUF_FULL} - if an attempt to write data was made to the OS, but
* no data was accepted
*
* @throws IOException If an I/O exception occurs during write.
*/
private int writeBytesMultiple(
ChannelOutboundBuffer in, ByteBuffer[] nioBuffers, int nioBufferCnt, long expectedWrittenBytes,
long maxBytesPerGatheringWrite) throws IOException {
assert expectedWrittenBytes != 0;
if (expectedWrittenBytes > maxBytesPerGatheringWrite) {
expectedWrittenBytes = maxBytesPerGatheringWrite;
}
final long localWrittenBytes = socket.writev(nioBuffers, 0, nioBufferCnt, expectedWrittenBytes);
if (localWrittenBytes > 0) {
adjustMaxBytesPerGatheringWrite(expectedWrittenBytes, localWrittenBytes, maxBytesPerGatheringWrite);
in.removeBytes(localWrittenBytes);
return 1;
}
return WRITE_STATUS_SNDBUF_FULL;
}
/**
* Write a {@link DefaultFileRegion}
* @param in the collection which contains objects to write.
* @param region the {@link DefaultFileRegion} from which the bytes should be written
* @return The value that should be decremented from the write quantum which starts at
* {@link ChannelConfig#getWriteSpinCount()}. The typical use cases are as follows:
*
* - 0 - if no write was attempted. This is appropriate if an empty {@link ByteBuf} (or other empty content)
* is encountered
* - 1 - if a single call to write data was made to the OS
* - {@link ChannelUtils#WRITE_STATUS_SNDBUF_FULL} - if an attempt to write data was made to the OS, but
* no data was accepted
*
*/
private int writeDefaultFileRegion(ChannelOutboundBuffer in, DefaultFileRegion region) throws Exception {
final long offset = region.transferred();
final long regionCount = region.count();
if (offset >= regionCount) {
in.remove();
return 0;
}
final long flushedAmount = socket.sendFile(region, region.position(), offset, regionCount - offset);
if (flushedAmount > 0) {
in.progress(flushedAmount);
if (region.transferred() >= regionCount) {
in.remove();
}
return 1;
} else if (flushedAmount == 0) {
validateFileRegion(region, offset);
}
return WRITE_STATUS_SNDBUF_FULL;
}
/**
* Write a {@link FileRegion}
* @param in the collection which contains objects to write.
* @param region the {@link FileRegion} from which the bytes should be written
* @return The value that should be decremented from the write quantum which starts at
* {@link ChannelConfig#getWriteSpinCount()}. The typical use cases are as follows:
*
* - 0 - if no write was attempted. This is appropriate if an empty {@link ByteBuf} (or other empty content)
* is encountered
* - 1 - if a single call to write data was made to the OS
* - {@link ChannelUtils#WRITE_STATUS_SNDBUF_FULL} - if an attempt to write data was made to the OS, but
* no data was accepted
*
*/
private int writeFileRegion(ChannelOutboundBuffer in, FileRegion region) throws Exception {
if (region.transferred() >= region.count()) {
in.remove();
return 0;
}
if (byteChannel == null) {
byteChannel = new EpollSocketWritableByteChannel();
}
final long flushedAmount = region.transferTo(byteChannel, region.transferred());
if (flushedAmount > 0) {
in.progress(flushedAmount);
if (region.transferred() >= region.count()) {
in.remove();
}
return 1;
}
return WRITE_STATUS_SNDBUF_FULL;
}
@Override
protected void doWrite(ChannelOutboundBuffer in) throws Exception {
int writeSpinCount = config().getWriteSpinCount();
do {
final int msgCount = in.size();
// Do gathering write if the outbound buffer entries start with more than one ByteBuf.
if (msgCount > 1 && in.current() instanceof ByteBuf) {
writeSpinCount -= doWriteMultiple(in);
} else if (msgCount == 0) {
// Wrote all messages.
clearFlag(Native.EPOLLOUT);
// Return here so we not set the EPOLLOUT flag.
return;
} else { // msgCount == 1
writeSpinCount -= doWriteSingle(in);
}
// We do not break the loop here even if the outbound buffer was flushed completely,
// because a user might have triggered another write and flush when we notify his or her
// listeners.
} while (writeSpinCount > 0);
if (writeSpinCount == 0) {
// It is possible that we have set EPOLLOUT, woken up by EPOLL because the socket is writable, and then use
// our write quantum. In this case we no longer want to set the EPOLLOUT flag because the socket is still
// writable (as far as we know). We will find out next time we attempt to write if the socket is writable
// and set the EPOLLOUT if necessary.
clearFlag(Native.EPOLLOUT);
// We used our writeSpin quantum, and should try to write again later.
eventLoop().execute(flushTask);
} else {
// Underlying descriptor can not accept all data currently, so set the EPOLLOUT flag to be woken up
// when it can accept more data.
setFlag(Native.EPOLLOUT);
}
}
/**
* Attempt to write a single object.
* @param in the collection which contains objects to write.
* @return The value that should be decremented from the write quantum which starts at
* {@link ChannelConfig#getWriteSpinCount()}. The typical use cases are as follows:
*
* - 0 - if no write was attempted. This is appropriate if an empty {@link ByteBuf} (or other empty content)
* is encountered
* - 1 - if a single call to write data was made to the OS
* - {@link ChannelUtils#WRITE_STATUS_SNDBUF_FULL} - if an attempt to write data was made to the OS, but
* no data was accepted
*
* @throws Exception If an I/O error occurs.
*/
protected int doWriteSingle(ChannelOutboundBuffer in) throws Exception {
// The outbound buffer contains only one message or it contains a file region.
Object msg = in.current();
if (msg instanceof ByteBuf) {
return writeBytes(in, (ByteBuf) msg);
} else if (msg instanceof DefaultFileRegion) {
return writeDefaultFileRegion(in, (DefaultFileRegion) msg);
} else if (msg instanceof FileRegion) {
return writeFileRegion(in, (FileRegion) msg);
} else if (msg instanceof SpliceOutTask) {
if (!((SpliceOutTask) msg).spliceOut()) {
return WRITE_STATUS_SNDBUF_FULL;
}
in.remove();
return 1;
} else {
// Should never reach here.
throw new Error();
}
}
/**
* Attempt to write multiple {@link ByteBuf} objects.
* @param in the collection which contains objects to write.
* @return The value that should be decremented from the write quantum which starts at
* {@link ChannelConfig#getWriteSpinCount()}. The typical use cases are as follows:
*
* - 0 - if no write was attempted. This is appropriate if an empty {@link ByteBuf} (or other empty content)
* is encountered
* - 1 - if a single call to write data was made to the OS
* - {@link ChannelUtils#WRITE_STATUS_SNDBUF_FULL} - if an attempt to write data was made to the OS, but
* no data was accepted
*
* @throws Exception If an I/O error occurs.
*/
private int doWriteMultiple(ChannelOutboundBuffer in) throws Exception {
final long maxBytesPerGatheringWrite = config().getMaxBytesPerGatheringWrite();
IovArray array = ((EpollEventLoop) eventLoop()).cleanIovArray();
array.maxBytes(maxBytesPerGatheringWrite);
in.forEachFlushedMessage(array);
if (array.count() >= 1) {
// TODO: Handle the case where cnt == 1 specially.
return writeBytesMultiple(in, array);
}
// cnt == 0, which means the outbound buffer contained empty buffers only.
in.removeBytes(0);
return 0;
}
@Override
protected Object filterOutboundMessage(Object msg) {
if (msg instanceof ByteBuf) {
ByteBuf buf = (ByteBuf) msg;
return UnixChannelUtil.isBufferCopyNeededForWrite(buf)? newDirectBuffer(buf): buf;
}
if (msg instanceof FileRegion || msg instanceof SpliceOutTask) {
return msg;
}
throw new UnsupportedOperationException(
"unsupported message type: " + StringUtil.simpleClassName(msg) + EXPECTED_TYPES);
}
@UnstableApi
@Override
protected final void doShutdownOutput() throws Exception {
socket.shutdown(false, true);
}
private void shutdownInput0(final ChannelPromise promise) {
try {
socket.shutdown(true, false);
promise.setSuccess();
} catch (Throwable cause) {
promise.setFailure(cause);
}
}
@Override
public boolean isOutputShutdown() {
return socket.isOutputShutdown();
}
@Override
public boolean isInputShutdown() {
return socket.isInputShutdown();
}
@Override
public boolean isShutdown() {
return socket.isShutdown();
}
@Override
public ChannelFuture shutdownOutput() {
return shutdownOutput(newPromise());
}
@Override
public ChannelFuture shutdownOutput(final ChannelPromise promise) {
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
public ChannelFuture shutdownInput(final ChannelPromise promise) {
Executor closeExecutor = ((EpollStreamUnsafe) unsafe()).prepareToClose();
if (closeExecutor != null) {
closeExecutor.execute(new Runnable() {
@Override
public void run() {
shutdownInput0(promise);
}
});
} else {
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();
}
}
@Override
protected void doClose() throws Exception {
try {
// Calling super.doClose() first so spliceTo(...) will fail on next call.
super.doClose();
} finally {
safeClosePipe(pipeIn);
safeClosePipe(pipeOut);
clearSpliceQueue();
}
}
private void clearSpliceQueue() {
Queue sQueue = spliceQueue;
if (sQueue == null) {
return;
}
ClosedChannelException exception = null;
for (;;) {
SpliceInTask task = sQueue.poll();
if (task == null) {
break;
}
if (exception == null) {
exception = new ClosedChannelException();
}
task.promise.tryFailure(exception);
}
}
private static void safeClosePipe(FileDescriptor fd) {
if (fd != null) {
try {
fd.close();
} catch (IOException e) {
logger.warn("Error while closing a pipe", e);
}
}
}
class EpollStreamUnsafe extends AbstractEpollUnsafe {
// Overridden here just to be able to access this method from AbstractEpollStreamChannel
@Override
protected Executor prepareToClose() {
return super.prepareToClose();
}
private void handleReadException(ChannelPipeline pipeline, ByteBuf byteBuf, Throwable cause, boolean close,
EpollRecvByteAllocatorHandle allocHandle) {
if (byteBuf != null) {
if (byteBuf.isReadable()) {
readPending = false;
pipeline.fireChannelRead(byteBuf);
} else {
byteBuf.release();
}
}
allocHandle.readComplete();
pipeline.fireChannelReadComplete();
pipeline.fireExceptionCaught(cause);
// If oom will close the read event, release connection.
// See https://github.com/netty/netty/issues/10434
if (close || cause instanceof OutOfMemoryError || cause instanceof IOException) {
shutdownInput(false);
}
}
@Override
EpollRecvByteAllocatorHandle newEpollHandle(RecvByteBufAllocator.ExtendedHandle handle) {
return new EpollRecvByteAllocatorStreamingHandle(handle);
}
@Override
void epollInReady() {
final ChannelConfig config = config();
if (shouldBreakEpollInReady(config)) {
clearEpollIn0();
return;
}
final EpollRecvByteAllocatorHandle allocHandle = recvBufAllocHandle();
allocHandle.edgeTriggered(isFlagSet(Native.EPOLLET));
final ChannelPipeline pipeline = pipeline();
final ByteBufAllocator allocator = config.getAllocator();
allocHandle.reset(config);
epollInBefore();
ByteBuf byteBuf = null;
boolean close = false;
Queue sQueue = null;
try {
do {
if (sQueue != null || (sQueue = spliceQueue) != null) {
SpliceInTask spliceTask = sQueue.peek();
if (spliceTask != null) {
boolean spliceInResult = spliceTask.spliceIn(allocHandle);
if (allocHandle.isReceivedRdHup()) {
shutdownInput(true);
}
if (spliceInResult) {
// We need to check if it is still active as if not we removed all SpliceTasks in
// doClose(...)
if (isActive()) {
sQueue.remove();
}
continue;
} else {
break;
}
}
}
// we use a direct buffer here as the native implementations only be able
// to handle direct buffers.
byteBuf = allocHandle.allocate(allocator);
allocHandle.lastBytesRead(doReadBytes(byteBuf));
if (allocHandle.lastBytesRead() <= 0) {
// nothing was read, release the buffer.
byteBuf.release();
byteBuf = null;
close = allocHandle.lastBytesRead() < 0;
if (close) {
// There is nothing left to read as we received an EOF.
readPending = false;
}
break;
}
allocHandle.incMessagesRead(1);
readPending = false;
pipeline.fireChannelRead(byteBuf);
byteBuf = null;
if (shouldBreakEpollInReady(config)) {
// We need to do this for two reasons:
//
// - If the input was shutdown in between (which may be the case when the user did it in the
// fireChannelRead(...) method we should not try to read again to not produce any
// miss-leading exceptions.
//
// - If the user closes the channel we need to ensure we not try to read from it again as
// the filedescriptor may be re-used already by the OS if the system is handling a lot of
// concurrent connections and so needs a lot of filedescriptors. If not do this we risk
// reading data from a filedescriptor that belongs to another socket then the socket that
// was "wrapped" by this Channel implementation.
break;
}
} while (allocHandle.continueReading());
allocHandle.readComplete();
pipeline.fireChannelReadComplete();
if (close) {
shutdownInput(false);
}
} catch (Throwable t) {
handleReadException(pipeline, byteBuf, t, close, allocHandle);
} finally {
if (sQueue == null) {
epollInFinally(config);
} else {
if (!config.isAutoRead()) {
clearEpollIn();
}
}
}
}
}
private void addToSpliceQueue(final SpliceInTask task) {
Queue sQueue = spliceQueue;
if (sQueue == null) {
synchronized (this) {
sQueue = spliceQueue;
if (sQueue == null) {
spliceQueue = sQueue = PlatformDependent.newMpscQueue();
}
}
}
sQueue.add(task);
}
protected abstract class SpliceInTask {
final ChannelPromise promise;
int len;
protected SpliceInTask(int len, ChannelPromise promise) {
this.promise = promise;
this.len = len;
}
abstract boolean spliceIn(RecvByteBufAllocator.Handle handle);
protected final int spliceIn(FileDescriptor pipeOut, RecvByteBufAllocator.Handle handle) throws IOException {
// calculate the maximum amount of data we are allowed to splice
int length = Math.min(handle.guess(), len);
int splicedIn = 0;
for (;;) {
// Splicing until there is nothing left to splice.
int localSplicedIn = Native.splice(socket.intValue(), -1, pipeOut.intValue(), -1, length);
handle.lastBytesRead(localSplicedIn);
if (localSplicedIn == 0) {
break;
}
splicedIn += localSplicedIn;
length -= localSplicedIn;
}
return splicedIn;
}
}
// Let it directly implement channelFutureListener as well to reduce object creation.
private final class SpliceInChannelTask extends SpliceInTask implements ChannelFutureListener {
private final AbstractEpollStreamChannel ch;
SpliceInChannelTask(AbstractEpollStreamChannel ch, int len, ChannelPromise promise) {
super(len, promise);
this.ch = ch;
}
@Override
public void operationComplete(ChannelFuture future) throws Exception {
if (!future.isSuccess()) {
promise.setFailure(future.cause());
}
}
@Override
public boolean spliceIn(RecvByteBufAllocator.Handle handle) {
assert ch.eventLoop().inEventLoop();
if (len == 0) {
promise.setSuccess();
return true;
}
try {
// We create the pipe on the target channel as this will allow us to just handle pending writes
// later in a correct fashion without get into any ordering issues when spliceTo(...) is called
// on multiple Channels pointing to one target Channel.
FileDescriptor pipeOut = ch.pipeOut;
if (pipeOut == null) {
// Create a new pipe as non was created before.
FileDescriptor[] pipe = pipe();
ch.pipeIn = pipe[0];
pipeOut = ch.pipeOut = pipe[1];
}
int splicedIn = spliceIn(pipeOut, handle);
if (splicedIn > 0) {
// Integer.MAX_VALUE is a special value which will result in splice forever.
if (len != Integer.MAX_VALUE) {
len -= splicedIn;
}
// Depending on if we are done with splicing inbound data we set the right promise for the
// outbound splicing.
final ChannelPromise splicePromise;
if (len == 0) {
splicePromise = promise;
} else {
splicePromise = ch.newPromise().addListener(this);
}
boolean autoRead = config().isAutoRead();
// Just call unsafe().write(...) and flush() as we not want to traverse the whole pipeline for this
// case.
ch.unsafe().write(new SpliceOutTask(ch, splicedIn, autoRead), splicePromise);
ch.unsafe().flush();
if (autoRead && !splicePromise.isDone()) {
// Write was not done which means the target channel was not writable. In this case we need to
// disable reading until we are done with splicing to the target channel because:
//
// - The user may want to to trigger another splice operation once the splicing was complete.
config().setAutoRead(false);
}
}
return len == 0;
} catch (Throwable cause) {
promise.setFailure(cause);
return true;
}
}
}
private final class SpliceOutTask {
private final AbstractEpollStreamChannel ch;
private final boolean autoRead;
private int len;
SpliceOutTask(AbstractEpollStreamChannel ch, int len, boolean autoRead) {
this.ch = ch;
this.len = len;
this.autoRead = autoRead;
}
public boolean spliceOut() throws Exception {
assert ch.eventLoop().inEventLoop();
try {
int splicedOut = Native.splice(ch.pipeIn.intValue(), -1, ch.socket.intValue(), -1, len);
len -= splicedOut;
if (len == 0) {
if (autoRead) {
// AutoRead was used and we spliced everything so start reading again
config().setAutoRead(true);
}
return true;
}
return false;
} catch (IOException e) {
if (autoRead) {
// AutoRead was used and we spliced everything so start reading again
config().setAutoRead(true);
}
throw e;
}
}
}
private final class SpliceFdTask extends SpliceInTask {
private final FileDescriptor fd;
private final ChannelPromise promise;
private int offset;
SpliceFdTask(FileDescriptor fd, int offset, int len, ChannelPromise promise) {
super(len, promise);
this.fd = fd;
this.promise = promise;
this.offset = offset;
}
@Override
public boolean spliceIn(RecvByteBufAllocator.Handle handle) {
assert eventLoop().inEventLoop();
if (len == 0) {
promise.setSuccess();
return true;
}
try {
FileDescriptor[] pipe = pipe();
FileDescriptor pipeIn = pipe[0];
FileDescriptor pipeOut = pipe[1];
try {
int splicedIn = spliceIn(pipeOut, handle);
if (splicedIn > 0) {
// Integer.MAX_VALUE is a special value which will result in splice forever.
if (len != Integer.MAX_VALUE) {
len -= splicedIn;
}
do {
int splicedOut = Native.splice(pipeIn.intValue(), -1, fd.intValue(), offset, splicedIn);
offset += splicedOut;
splicedIn -= splicedOut;
} while (splicedIn > 0);
if (len == 0) {
promise.setSuccess();
return true;
}
}
return false;
} finally {
safeClosePipe(pipeIn);
safeClosePipe(pipeOut);
}
} catch (Throwable cause) {
promise.setFailure(cause);
return true;
}
}
}
private final class EpollSocketWritableByteChannel extends SocketWritableByteChannel {
EpollSocketWritableByteChannel() {
super(socket);
assert fd == socket;
}
@Override
protected int write(final ByteBuffer buf, final int pos, final int limit) throws IOException {
return socket.send(buf, pos, limit);
}
@Override
protected ByteBufAllocator alloc() {
return AbstractEpollStreamChannel.this.alloc();
}
}
}