/*
* Copyright (C)2009 - SSHJ Contributors
*
* 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 net.schmizz.sshj.sftp;
import net.schmizz.concurrent.Promise;
import net.schmizz.sshj.common.SSHException;
import org.slf4j.Logger;
import java.io.IOException;
import java.io.InputStream;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
public class PacketReader extends Thread {
/**
* Logger
*/
private final Logger log;
private final InputStream in;
private final Map<Long, Promise<Response, SFTPException>> promises = new ConcurrentHashMap<Long, Promise<Response, SFTPException>>();
private final SFTPPacket<Response> packet = new SFTPPacket<Response>();
private final byte[] lenBuf = new byte[4];
private final SFTPEngine engine;
public PacketReader(SFTPEngine engine) {
this.engine = engine;
log = engine.getLoggerFactory().getLogger(getClass());
this.in = engine.getSubsystem().getInputStream();
setName("sftp reader");
}
private void readIntoBuffer(byte[] buf, int off, int len)
throws IOException {
int count = 0;
int read = 0;
while (count < len && ((read = in.read(buf, off + count, len - count)) != -1))
count += read;
if (read == -1)
throw new SFTPException("EOF while reading packet");
}
private int getPacketLength()
throws IOException {
readIntoBuffer(lenBuf, 0, lenBuf.length);
final long len = (lenBuf[0] << 24 & 0xff000000L
| lenBuf[1] << 16 & 0x00ff0000L
| lenBuf[2] << 8 & 0x0000ff00L
| lenBuf[3] & 0x000000ffL);
if (len > SFTPPacket.MAX_SIZE) {
throw new SSHException(String.format("Indicated packet length %d too large", len));
}
return (int) len;
}
public SFTPPacket<Response> readPacket()
throws IOException {
final int len = getPacketLength();
packet.clear();
packet.ensureCapacity(len);
readIntoBuffer(packet.array(), 0, len);
packet.wpos(len);
return packet;
}
@Override
public void run() {
try {
while (!isInterrupted()) {
readPacket();
handle();
}
} catch (IOException e) {
for (Promise<Response, SFTPException> promise : promises.values())
promise.deliverError(e);
}
}
public void handle()
throws SFTPException {
Response resp = new Response(packet, engine.getOperativeProtocolVersion());
Promise<Response, SFTPException> promise = promises.remove(resp.getRequestID());
log.debug("Received {} packet", resp.getType());
if (promise == null)
throw new SFTPException("Received [" + resp.readType() + "] response for request-id " + resp.getRequestID()
+ ", no such request was made");
else
promise.deliver(resp);
}
public Promise<Response, SFTPException> expectResponseTo(long requestId) {
final Promise<Response, SFTPException> promise
= new Promise<Response, SFTPException>("sftp / " + requestId, SFTPException.chainer, engine.getLoggerFactory());
promises.put(requestId, promise);
return promise;
}
}