/*
* Copyright (c) 2012 the original author or authors.
*
* 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 org.eclipse.jetty.spdy.generator;
import java.nio.ByteBuffer;
import org.eclipse.jetty.spdy.ByteBufferPool;
import org.eclipse.jetty.spdy.SessionException;
import org.eclipse.jetty.spdy.api.SPDY;
import org.eclipse.jetty.spdy.api.SessionStatus;
import org.eclipse.jetty.spdy.frames.ControlFrame;
import org.eclipse.jetty.spdy.frames.SynReplyFrame;
public class SynReplyGenerator extends ControlFrameGenerator
{
private final HeadersBlockGenerator headersBlockGenerator;
public SynReplyGenerator(ByteBufferPool bufferPool, HeadersBlockGenerator headersBlockGenerator)
{
super(bufferPool);
this.headersBlockGenerator = headersBlockGenerator;
}
@Override
public ByteBuffer generate(ControlFrame frame)
{
SynReplyFrame synReply = (SynReplyFrame)frame;
short version = synReply.getVersion();
ByteBuffer headersBuffer = headersBlockGenerator.generate(version, synReply.getHeaders());
int frameBodyLength = getFrameDataLength(version);
int frameLength = frameBodyLength + headersBuffer.remaining();
if (frameLength > 0xFF_FF_FF)
{
// Too many headers, but unfortunately we have already modified the compression
// context, so we have no other choice than tear down the connection.
throw new SessionException(SessionStatus.PROTOCOL_ERROR, "Too many headers");
}
int totalLength = ControlFrame.HEADER_LENGTH + frameLength;
ByteBuffer buffer = getByteBufferPool().acquire(totalLength, true);
generateControlFrameHeader(synReply, frameLength, buffer);
buffer.putInt(synReply.getStreamId() & 0x7F_FF_FF_FF);
writeAdditional(version, buffer);
buffer.put(headersBuffer);
buffer.flip();
return buffer;
}
private int getFrameDataLength(short version)
{
switch (version)
{
case SPDY.V2:
return 6;
case SPDY.V3:
return 4;
default:
// Here the version is trusted to be correct; if it's not
// then it's a bug rather than an application error
throw new IllegalStateException();
}
}
private void writeAdditional(short version, ByteBuffer buffer)
{
switch (version)
{
case SPDY.V2:
buffer.putShort((short)0);
break;
case SPDY.V3:
break;
default:
// Here the version is trusted to be correct; if it's not
// then it's a bug rather than an application error
throw new IllegalStateException();
}
}
}