org.eclipse.jetty.spdy.parser.SettingsBodyParser Maven / Gradle / Ivy
//
// ========================================================================
// Copyright (c) 1995-2013 Mort Bay Consulting Pty. Ltd.
// ------------------------------------------------------------------------
// All rights reserved. This program and the accompanying materials
// are made available under the terms of the Eclipse Public License v1.0
// and Apache License v2.0 which accompanies this distribution.
//
// The Eclipse Public License is available at
// http://www.eclipse.org/legal/epl-v10.html
//
// The Apache License v2.0 is available at
// http://www.opensource.org/licenses/apache2.0.php
//
// You may elect to redistribute this code under either of these licenses.
// ========================================================================
//
package org.eclipse.jetty.spdy.parser;
import java.nio.ByteBuffer;
import org.eclipse.jetty.spdy.api.SPDY;
import org.eclipse.jetty.spdy.api.Settings;
import org.eclipse.jetty.spdy.frames.SettingsFrame;
public class SettingsBodyParser extends ControlFrameBodyParser
{
private final Settings settings = new Settings();
private final ControlFrameParser controlFrameParser;
private State state = State.COUNT;
private int cursor;
private int count;
private int idAndFlags;
private int value;
public SettingsBodyParser(ControlFrameParser controlFrameParser)
{
this.controlFrameParser = controlFrameParser;
}
@Override
public boolean parse(ByteBuffer buffer)
{
while (buffer.hasRemaining())
{
switch (state)
{
case COUNT:
{
if (buffer.remaining() >= 4)
{
count = buffer.getInt();
state = State.ID_FLAGS;
}
else
{
state = State.COUNT_BYTES;
cursor = 4;
}
break;
}
case COUNT_BYTES:
{
byte currByte = buffer.get();
--cursor;
count += (currByte & 0xFF) << 8 * cursor;
if (cursor == 0)
state = State.ID_FLAGS;
break;
}
case ID_FLAGS:
{
if (buffer.remaining() >= 4)
{
idAndFlags = convertIdAndFlags(controlFrameParser.getVersion(), buffer.getInt());
state = State.VALUE;
}
else
{
state = State.ID_FLAGS_BYTES;
cursor = 4;
}
break;
}
case ID_FLAGS_BYTES:
{
byte currByte = buffer.get();
--cursor;
value += (currByte & 0xFF) << 8 * cursor;
if (cursor == 0)
{
idAndFlags = convertIdAndFlags(controlFrameParser.getVersion(), value);
state = State.VALUE;
}
break;
}
case VALUE:
{
if (buffer.remaining() >= 4)
{
value = buffer.getInt();
if (onPair())
return true;
}
else
{
state = State.VALUE_BYTES;
cursor = 4;
value = 0;
}
break;
}
case VALUE_BYTES:
{
byte currByte = buffer.get();
--cursor;
value += (currByte & 0xFF) << 8 * cursor;
if (cursor == 0)
{
if (onPair())
return true;
}
break;
}
default:
{
throw new IllegalStateException();
}
}
}
return false;
}
private int convertIdAndFlags(short version, int idAndFlags)
{
switch (version)
{
case SPDY.V2:
{
// A bug in the Chromium implementation forces v2 to have
// 3 ID bytes little endian + 1 byte of flags
// Here we normalize this to conform with v3, which is
// 1 bytes of flag + 3 ID bytes big endian
int result = (idAndFlags & 0x00_00_00_FF) << 24;
result += (idAndFlags & 0x00_00_FF_00) << 8;
result += (idAndFlags & 0x00_FF_00_00) >>> 8;
result += (idAndFlags & 0xFF_00_00_00) >>> 24;
return result;
}
case SPDY.V3:
{
return idAndFlags;
}
default:
{
throw new IllegalStateException();
}
}
}
private boolean onPair()
{
int id = idAndFlags & 0x00_FF_FF_FF;
byte flags = (byte)((idAndFlags & 0xFF_00_00_00) >>> 24);
settings.put(new Settings.Setting(Settings.ID.from(id), Settings.Flag.from(flags), value));
state = State.ID_FLAGS;
idAndFlags = 0;
value = 0;
--count;
if (count == 0)
{
onSettings();
return true;
}
return false;
}
private void onSettings()
{
SettingsFrame frame = new SettingsFrame(controlFrameParser.getVersion(), controlFrameParser.getFlags(), new Settings(settings, true));
controlFrameParser.onControlFrame(frame);
reset();
}
private void reset()
{
settings.clear();
state = State.COUNT;
cursor = 0;
count = 0;
idAndFlags = 0;
value = 0;
}
private enum State
{
COUNT, COUNT_BYTES, ID_FLAGS, ID_FLAGS_BYTES, VALUE, VALUE_BYTES
}
}