/* * 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.conduits; import io.undertow.server.Connectors; import io.undertow.server.HttpServerExchange; import io.undertow.util.ConduitFactory; import org.xnio.conduits.StreamSinkConduit; import java.util.zip.CRC32; import java.util.zip.Deflater; /** * @author Stuart Douglas */ public class GzipStreamSinkConduit extends DeflatingStreamSinkConduit { /* * GZIP header magic number. */ private static final int GZIP_MAGIC = 0x8b1f; private static final byte[] HEADER = new byte[]{ (byte) GZIP_MAGIC, // Magic number (short) (byte) (GZIP_MAGIC >> 8), // Magic number (short) Deflater.DEFLATED, // Compression method (CM) 0, // Flags (FLG) 0, // Modification time MTIME (int) 0, // Modification time MTIME (int) 0, // Modification time MTIME (int) 0, // Modification time MTIME (int) 0, // Extra flags (XFLG) 0 // Operating system (OS) }; /** * CRC-32 of uncompressed data. */ protected CRC32 crc = new CRC32(); public GzipStreamSinkConduit(ConduitFactory<StreamSinkConduit> conduitFactory, HttpServerExchange exchange) { this(conduitFactory, exchange, Deflater.DEFAULT_COMPRESSION); } public GzipStreamSinkConduit( ConduitFactory<StreamSinkConduit> conduitFactory, HttpServerExchange exchange, int deflateLevel) { super(conduitFactory, exchange, deflateLevel); writeHeader(); Connectors.updateResponseBytesSent(exchange, HEADER.length); } private void writeHeader() { currentBuffer.getBuffer().put(HEADER); } @Override protected void preDeflate(byte[] data) { crc.update(data); } @Override protected byte[] getTrailer() { byte[] ret = new byte[8]; int checksum = (int) crc.getValue(); int total = deflater.getTotalIn(); ret[0] = (byte) ((checksum) & 0xFF); ret[1] = (byte) ((checksum >> 8) & 0xFF); ret[2] = (byte) ((checksum >> 16) & 0xFF); ret[3] = (byte) ((checksum >> 24) & 0xFF); ret[4] = (byte) ((total) & 0xFF); ret[5] = (byte) ((total >> 8) & 0xFF); ret[6] = (byte) ((total >> 16) & 0xFF); ret[7] = (byte) ((total >> 24) & 0xFF); return ret; } }