/*
* 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.util;
import org.xnio.channels.StreamSinkChannel;
import org.xnio.conduits.AbstractStreamSourceConduit;
import org.xnio.conduits.StreamSourceConduit;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
/**
* @author Stuart Douglas
*/
public class SingleByteStreamSourceConduit extends AbstractStreamSourceConduit<StreamSourceConduit> {
private final int singleByteReads;
private int state = 0;
/**
* Construct a new instance.
*
* @param next the delegate conduit to set
* @param singleByteReads
*/
public SingleByteStreamSourceConduit(StreamSourceConduit next, int singleByteReads) {
super(next);
this.singleByteReads = singleByteReads;
}
@Override
public int read(ByteBuffer dst) throws IOException {
if (state > singleByteReads || dst.remaining() == 1) {
//we always let a single byte read through, otherwise SSL renegotiation breaks
return next.read(dst);
}
if (state++ % 2 == 0) {
wakeupIfSsl();
return 0;
} else {
if (dst.remaining() == 0) {
return 0;
}
int limit = dst.limit();
try {
dst.limit(dst.position() + 1);
int read = next.read(dst);
if(read != -1) {
wakeupIfSsl();
}
return read;
} finally {
dst.limit(limit);
}
}
}
private void wakeupIfSsl() {
//todo: work around a bug in the SSL channel where the read listener will not be invoked if there is more data in the buffer
if(isReadResumed() && next.getClass().getSimpleName().startsWith("Jsse")) {
wakeupReads();
}
}
@Override
public long read(ByteBuffer[] dsts, int offs, int len) throws IOException {
if (state > singleByteReads) {
return next.read(dsts, offs, len);
}
if (state++ % 2 == 0) {
return 0;
} else {
ByteBuffer dst = null;
for (int i = offs; i < offs + len; ++i) {
if (dsts[i].hasRemaining()) {
dst = dsts[i];
break;
}
}
if (dst == null) {
return 0;
}
int limit = dst.limit();
try {
dst.limit(dst.position() + 1);
return next.read(dst);
} finally {
dst.limit(limit);
}
}
}
@Override
public long transferTo(long position, long count, FileChannel target) throws IOException {
if (state > singleByteReads) {
return next.transferTo(position, count, target);
}
if (state++ % 2 == 0) {
return 0;
} else {
return next.transferTo(position, count == 0 ? 0 : count, target);
}
}
@Override
public long transferTo(long count, ByteBuffer throughBuffer, StreamSinkChannel target) throws IOException {
if (state > singleByteReads) {
return next.transferTo(count, throughBuffer, target);
}
if (state++ % 2 == 0) {
throughBuffer.position(throughBuffer.limit());
return 0;
} else {
return next.transferTo(count == 0 ? 0 : count, throughBuffer, target);
}
}
}