/*
* JBoss, Home of Professional Open Source.
* Copyright 2014 Red Hat, Inc., and individual contributors
* as indicated by the @author tags.
*
* Licensed 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.undertow.conduits;
import org.xnio.Buffers;
import org.xnio.channels.FixedLengthOverflowException;
import org.xnio.channels.FixedLengthUnderflowException;
import org.xnio.channels.StreamSourceChannel;
import org.xnio.conduits.AbstractStreamSinkConduit;
import org.xnio.conduits.Conduits;
import org.xnio.conduits.StreamSinkConduit;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.ClosedChannelException;
import java.nio.channels.FileChannel;
import java.util.concurrent.TimeUnit;
import static java.lang.Math.min;
import static org.xnio.Bits.allAreClear;
import static org.xnio.Bits.allAreSet;
import static org.xnio.Bits.anyAreSet;
import static org.xnio.Bits.longBitMask;
/**
* A channel which writes a fixed amount of data. A listener is called once the data has been written.
*
* @author <a href="mailto:david.lloyd@redhat.com">David M. Lloyd</a>
*/
public abstract class AbstractFixedLengthStreamSinkConduit extends AbstractStreamSinkConduit<StreamSinkConduit> {
private int config;
private long state;
private boolean broken = false;
private static final int CONF_FLAG_CONFIGURABLE = 1 << 0;
private static final int CONF_FLAG_PASS_CLOSE = 1 << 1;
private static final long FLAG_CLOSE_REQUESTED = 1L << 63L;
private static final long FLAG_CLOSE_COMPLETE = 1L << 62L;
private static final long FLAG_FINISHED_CALLED = 1L << 61L;
private static final long MASK_COUNT = longBitMask(0, 60);
/**
* Construct a new instance.
*
* @param next the next channel
* @param contentLength the content length
* @param configurable {@code true} if this instance should pass configuration to the next
* @param propagateClose {@code true} if this instance should pass close to the next
*/
public AbstractFixedLengthStreamSinkConduit(final StreamSinkConduit next, final long contentLength, final boolean configurable, final boolean propagateClose) {
super(next);
if (contentLength < 0L) {
throw new IllegalArgumentException("Content length must be greater than or equal to zero");
} else if (contentLength > MASK_COUNT) {
throw new IllegalArgumentException("Content length is too long");
}
config = (configurable ? CONF_FLAG_CONFIGURABLE : 0) | (propagateClose ? CONF_FLAG_PASS_CLOSE : 0);
this.state = contentLength;
}
protected void reset(long contentLength, boolean propagateClose) {
this.state = contentLength;
if (propagateClose) {
config |= CONF_FLAG_PASS_CLOSE;
} else {
config &= ~CONF_FLAG_PASS_CLOSE;
}
}
public int write(final ByteBuffer src) throws IOException {
long val = state;
final long remaining = val & MASK_COUNT;
if (!src.hasRemaining()) {
return 0;
}
if (allAreSet(val, FLAG_CLOSE_REQUESTED)) {
throw new ClosedChannelException();
}
int oldLimit = src.limit();
if (remaining == 0) {
throw new FixedLengthOverflowException();
} else if (src.remaining() > remaining) {
src.limit((int) (src.position() + remaining));
}
int res = 0;
try {
return res = next.write(src);
} catch (IOException e) {
broken = true;
throw e;
} finally {
src.limit(oldLimit);
exitWrite(val, (long) res);
}
}
public long write(final ByteBuffer[] srcs, final int offset, final int length) throws IOException {
if (length == 0) {
return 0L;
} else if (length == 1) {
return write(srcs[offset]);
}
long val = state;
final long remaining = val & MASK_COUNT;
if (allAreSet(val, FLAG_CLOSE_REQUESTED)) {
throw new ClosedChannelException();
}
long toWrite = Buffers.remaining(srcs, offset, length);
if (remaining == 0) {
throw new FixedLengthOverflowException();
}
int[] limits = null;
if (toWrite > remaining) {
limits = new int[length];
long r = remaining;
for (int i = offset; i < offset + length; ++i) {
limits[i - offset] = srcs[i].limit();
int br = srcs[i].remaining();
if(br < r) {
r -= br;
} else {
srcs[i].limit((int) (srcs[i].position() + r));
r = 0;
}
}
}
long res = 0L;
try {
return res = next.write(srcs, offset, length);
} catch (IOException e) {
broken = true;
throw e;
} finally {
if (limits != null) {
for (int i = offset; i < offset + length; ++i) {
srcs[i].limit(limits[i - offset]);
}
}
exitWrite(val, res);
}
}
@Override
public long writeFinal(ByteBuffer[] srcs, int offset, int length) throws IOException {
try {
return Conduits.writeFinalBasic(this, srcs, offset, length);
} catch (IOException e) {
broken = true;
throw e;
}
}
@Override
public int writeFinal(ByteBuffer src) throws IOException {
try {
return Conduits.writeFinalBasic(this, src);
} catch (IOException e) {
broken = true;
throw e;
}
}
public long transferFrom(final FileChannel src, final long position, final long count) throws IOException {
if (count == 0L) return 0L;
long val = state;
if (allAreSet(val, FLAG_CLOSE_REQUESTED)) {
throw new ClosedChannelException();
}
if (allAreClear(val, MASK_COUNT)) {
throw new FixedLengthOverflowException();
}
long res = 0L;
try {
return res = next.transferFrom(src, position, min(count, (val & MASK_COUNT)));
} catch (IOException e) {
broken = true;
throw e;
} finally {
exitWrite(val, res);
}
}
public long transferFrom(final StreamSourceChannel source, final long count, final ByteBuffer throughBuffer) throws IOException {
if (count == 0L) return 0L;
long val = state;
if (allAreSet(val, FLAG_CLOSE_REQUESTED)) {
throw new ClosedChannelException();
}
if (allAreClear(val, MASK_COUNT)) {
throw new FixedLengthOverflowException();
}
long res = 0L;
try {
return res = next.transferFrom(source, min(count, (val & MASK_COUNT)), throughBuffer);
} catch (IOException e) {
broken = true;
throw e;
} finally {
exitWrite(val, res);
}
}
public boolean flush() throws IOException {
long val = state;
if (anyAreSet(val, FLAG_CLOSE_COMPLETE)) {
return true;
}
boolean flushed = false;
try {
return flushed = next.flush();
} catch (IOException e) {
broken = true;
throw e;
} finally {
exitFlush(val, flushed);
}
}
public boolean isWriteResumed() {
// not perfect but not provably wrong either...
return allAreClear(state, FLAG_CLOSE_COMPLETE) && next.isWriteResumed();
}
public void wakeupWrites() {
long val = state;
if (anyAreSet(val, FLAG_CLOSE_COMPLETE)) {
return;
}
next.wakeupWrites();
}
public void terminateWrites() throws IOException {
final long val = enterShutdown();
if (anyAreSet(val, MASK_COUNT) && !broken) {
try {
throw new FixedLengthUnderflowException((val & MASK_COUNT) + " bytes remaining");
} finally {
next.truncateWrites();
}
} else if (allAreSet(config, CONF_FLAG_PASS_CLOSE)) {
next.terminateWrites();
}
}
public void awaitWritable() throws IOException {
next.awaitWritable();
}
public void awaitWritable(final long time, final TimeUnit timeUnit) throws IOException {
next.awaitWritable(time, timeUnit);
}
/**
* Get the number of remaining bytes in this fixed length channel.
*
* @return the number of remaining bytes
*/
public long getRemaining() {
return state & MASK_COUNT;
}
private void exitWrite(long oldVal, long consumed) {
long newVal = oldVal - consumed;
state = newVal;
}
private void exitFlush(long oldVal, boolean flushed) {
long newVal = oldVal;
boolean callFinish = false;
if ((anyAreSet(oldVal, FLAG_CLOSE_REQUESTED) || (newVal & MASK_COUNT) == 0L) && flushed) {
newVal |= FLAG_CLOSE_COMPLETE;
if (!anyAreSet(oldVal, FLAG_FINISHED_CALLED) && (newVal & MASK_COUNT) == 0L) {
newVal |= FLAG_FINISHED_CALLED;
callFinish = true;
}
state = newVal;
if (callFinish) {
channelFinished();
}
}
}
protected void channelFinished() {
}
private long enterShutdown() {
long oldVal, newVal;
oldVal = state;
if (anyAreSet(oldVal, FLAG_CLOSE_REQUESTED | FLAG_CLOSE_COMPLETE)) {
// no action necessary
return oldVal;
}
newVal = oldVal | FLAG_CLOSE_REQUESTED;
if (anyAreSet(oldVal, MASK_COUNT)) {
// error: channel not filled. set both close flags.
newVal |= FLAG_CLOSE_COMPLETE;
}
state = newVal;
return oldVal;
}
}