/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF 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 org.apache.sshd.common.channel;
import java.io.IOException;
import java.io.InputStream;
import java.io.InterruptedIOException;
import java.net.SocketException;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
import org.apache.sshd.common.util.Buffer;
/**
* TODO Add javadoc
*
* @author <a href="mailto:dev@mina.apache.org">Apache MINA SSHD Project</a>
*/
public class ChannelPipedInputStream extends InputStream {
private final Window localWindow;
private final Buffer buffer = new Buffer();
private final byte[] b = new byte[1];
private boolean closed;
private boolean eofSent;
private final Lock lock = new ReentrantLock();
private final Condition dataAvailable = lock.newCondition();
private int timeout = 0; // zero is infinite
/**
* {@link ChannelPipedOutputStream} is already closed and so we will not receive additional data.
* This is different from the {@link #closed}, which indicates that the reader of this {@link InputStream}
* will not be reading data any more.
*/
private boolean writerClosed;
public ChannelPipedInputStream(Window localWindow) {
this.localWindow = localWindow;
}
public void setTimeout(int timeout) {
this.timeout = timeout;
}
public int getTimeout() {
return timeout;
}
@Override
public int available() throws IOException {
lock.lock();
try {
int avail = buffer.available();
if (avail == 0 && writerClosed) {
return -1;
}
return avail;
} finally {
lock.unlock();
}
}
public int read() throws IOException {
synchronized (b) {
int l = read(b, 0, 1);
if (l == -1) {
return -1;
}
return ((int) b[0] & 0xff);
}
}
@Override
public int read(byte[] b, int off, int len) throws IOException {
int avail;
long startTime = System.currentTimeMillis();
lock.lock();
try {
for (;;) {
if (closed && writerClosed && eofSent || closed && !writerClosed) {
throw new IOException("Pipe closed");
}
if (buffer.available() > 0) {
break;
}
if (writerClosed) {
eofSent = true;
return -1; // no more data to read
}
try {
if (timeout > 0) {
long remaining = timeout - (System.currentTimeMillis() - startTime);
if (remaining <= 0) {
throw new SocketException("timeout");
}
dataAvailable.await(remaining, TimeUnit.MILLISECONDS);
} else {
dataAvailable.await();
}
} catch (InterruptedException e) {
throw (IOException) new InterruptedIOException().initCause(e);
}
}
if (len > buffer.available()) {
len = buffer.available();
}
buffer.getRawBytes(b, off, len);
if (buffer.rpos() > localWindow.getPacketSize() || buffer.available() == 0) {
buffer.compact();
}
avail = localWindow.getMaxSize() - buffer.available();
} finally {
lock.unlock();
}
localWindow.check(avail);
return len;
}
public void eof() {
lock.lock();
try {
writerClosed = true;
dataAvailable.signalAll();
} finally {
lock.unlock();
}
}
@Override
public void close() throws IOException {
lock.lock();
try {
closed = true;
dataAvailable.signalAll();
} finally {
lock.unlock();
}
}
public void receive(byte[] bytes, int off, int len) throws IOException {
lock.lock();
try {
if (writerClosed || closed) {
throw new IOException("Pipe closed");
}
buffer.putRawBytes(bytes, off, len);
dataAvailable.signalAll();
} finally {
lock.unlock();
}
localWindow.consume(len);
}
}