[#1481] Add a JdkZlibDecoder which has no dependencies

This commit is contained in:
Norman Maurer 2013-08-12 20:33:09 +02:00
parent 9acf130adb
commit 39cabcd36c
4 changed files with 453 additions and 6 deletions

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@ -0,0 +1,339 @@
/*
* Copyright 2013 The Netty Project
*
* The Netty Project 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 io.netty.handler.codec.compression;
import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandlerContext;
import java.util.List;
import java.util.zip.CRC32;
import java.util.zip.DataFormatException;
import java.util.zip.Deflater;
import java.util.zip.Inflater;
/**
* Decompress a {@link ByteBuf} using the inflate algorithm.
*/
public class JdkZlibDecoder extends ZlibDecoder {
private static final int FHCRC = 0x02;
private static final int FEXTRA = 0x04;
private static final int FNAME = 0x08;
private static final int FCOMMENT = 0x10;
private static final int FRESERVED = 0xE0;
private final Inflater inflater;
private final byte[] dictionary;
// GZIP related
private final CRC32 crc;
private enum GzipState {
HEADER_START,
HEADER_END,
FLG_READ,
XLEN_READ,
SKIP_FNAME,
SKIP_COMMENT,
PROCESS_FHCRC,
FOOTER_START,
}
private GzipState gzipState = GzipState.HEADER_START;
private int flags = -1;
private int xlen = -1;
private volatile boolean finished;
/**
* Creates a new instance with the default wrapper ({@link ZlibWrapper#ZLIB}).
*/
public JdkZlibDecoder() {
this(ZlibWrapper.ZLIB, null);
}
/**
* Creates a new instance with the specified preset dictionary. The wrapper
* is always {@link ZlibWrapper#ZLIB} because it is the only format that
* supports the preset dictionary.
*/
public JdkZlibDecoder(byte[] dictionary) {
this(ZlibWrapper.ZLIB, dictionary);
}
/**
* Creates a new instance with the specified wrapper.
* Be aware that only {@link ZlibWrapper#GZIP}, {@link ZlibWrapper#ZLIB} and {@link ZlibWrapper#NONE} are
* supported atm.
*/
public JdkZlibDecoder(ZlibWrapper wrapper) {
this(wrapper, null);
}
private JdkZlibDecoder(ZlibWrapper wrapper, byte[] dictionary) {
if (wrapper == null) {
throw new NullPointerException("wrapper");
}
switch (wrapper) {
case GZIP:
inflater = new Inflater(true);
crc = new CRC32();
break;
case NONE:
inflater = new Inflater(true);
crc = null;
break;
case ZLIB:
inflater = new Inflater();
crc = null;
break;
default:
throw new IllegalArgumentException("Only GZIP or ZLIB is supported, but you used " + wrapper);
}
this.dictionary = dictionary;
}
@Override
public boolean isClosed() {
return finished;
}
@Override
protected void decode(ChannelHandlerContext ctx, ByteBuf in, List<Object> out) throws Exception {
if (!in.isReadable() && finished) {
return;
}
if (crc != null) {
switch (gzipState) {
case FOOTER_START:
if (readGZIPFooter(in)) {
finished = true;
}
return;
default:
if (gzipState != GzipState.HEADER_END) {
if (!readGZIPHeader(in)) {
return;
}
}
}
}
int readableBytes = in.readableBytes();
if (in.hasArray()) {
inflater.setInput(in.array(), in.arrayOffset() + in.readerIndex(), in.readableBytes());
} else {
byte[] array = new byte[in.readableBytes()];
in.getBytes(in.readerIndex(), array);
inflater.setInput(array);
}
int maxOutputLength = inflater.getRemaining() << 1;
ByteBuf decompressed = ctx.alloc().heapBuffer(maxOutputLength);
try {
boolean readFooter = false;
while (!inflater.needsInput()) {
byte[] outArray = decompressed.array();
int outIndex = decompressed.arrayOffset() + decompressed.writerIndex();
int length = outArray.length - outIndex;
int outputLength = inflater.inflate(outArray, outIndex, length);
if (outputLength > 0) {
decompressed.writerIndex(decompressed.writerIndex() + outputLength);
if (crc != null) {
crc.update(outArray, outIndex, length);
}
} else {
if (inflater.needsDictionary()) {
if (dictionary == null) {
throw new DecompressionException(
"decompression failure, unable to set dictionary as non was specified");
}
inflater.setDictionary(dictionary);
}
}
if (inflater.finished()) {
if (crc == null) {
finished = true; // Do not decode anymore.
} else {
readFooter = true;
}
break;
}
}
in.skipBytes(readableBytes - inflater.getRemaining());
if (readFooter) {
gzipState = GzipState.FOOTER_START;
if (readGZIPFooter(in)) {
finished = true;
}
}
} catch (DataFormatException e) {
throw new DecompressionException("decompression failure", e);
} finally {
if (decompressed.isReadable()) {
out.add(decompressed);
} else {
decompressed.release();
}
}
}
@Override
protected void handlerRemoved0(ChannelHandlerContext ctx) throws Exception {
super.handlerRemoved0(ctx);
inflater.end();
}
private boolean readGZIPHeader(ByteBuf in) {
switch (gzipState) {
case HEADER_START:
if (in.readableBytes() < 10) {
return false;
}
// read magic numbers
int magic0 = in.readByte();
int magic1 = in.readByte();
if (magic0 != 31) {
throw new CompressionException("Input is not in the GZIP format");
}
crc.update(magic0);
crc.update(magic1);
int method = in.readUnsignedByte();
if (method != Deflater.DEFLATED) {
throw new CompressionException("Unsupported compression method "
+ method + " in the GZIP header");
}
crc.update(method);
flags = in.readUnsignedByte();
crc.update(flags);
if ((flags & FRESERVED) != 0) {
throw new CompressionException(
"Reserved flags are set in the GZIP header");
}
// mtime (int)
crc.update(in.readByte());
crc.update(in.readByte());
crc.update(in.readByte());
crc.update(in.readByte());
crc.update(in.readUnsignedByte()); // extra flags
crc.update(in.readUnsignedByte()); // operating system
gzipState = GzipState.FLG_READ;
case FLG_READ:
if ((flags & FEXTRA) != 0) {
if (in.readableBytes() < 2) {
return false;
}
int xlen1 = in.readUnsignedByte();
int xlen2 = in.readUnsignedByte();
crc.update(xlen1);
crc.update(xlen2);
xlen |= xlen1 << 8 | xlen2;
}
gzipState = GzipState.XLEN_READ;
case XLEN_READ:
if (xlen != -1) {
if (in.readableBytes() < xlen) {
return false;
}
byte[] xtra = new byte[xlen];
in.readBytes(xtra);
crc.update(xtra);
}
gzipState = GzipState.SKIP_FNAME;
case SKIP_FNAME:
if ((flags & FNAME) != 0) {
if (!in.isReadable()) {
return false;
}
do {
int b = in.readUnsignedByte();
crc.update(b);
if (b == 0x00) {
break;
}
} while (in.isReadable());
}
gzipState = GzipState.SKIP_COMMENT;
case SKIP_COMMENT:
if ((flags & FCOMMENT) != 0) {
if (!in.isReadable()) {
return false;
}
do {
int b = in.readUnsignedByte();
crc.update(b);
if (b == 0x00) {
break;
}
} while (in.isReadable());
}
gzipState = GzipState.PROCESS_FHCRC;
case PROCESS_FHCRC:
if ((flags & FHCRC) != 0) {
if (!in.isReadable()) {
return false;
}
int headerCrc = in.readShort();
int readCrc = (int) crc.getValue() & 0xffff;
if (headerCrc != readCrc) {
throw new CompressionException(
"Header CRC value missmatch. Expected: " + headerCrc + ", Got: " + readCrc);
}
}
crc.reset();
gzipState = GzipState.HEADER_END;
case HEADER_END:
return true;
default:
throw new IllegalStateException();
}
}
private boolean readGZIPFooter(ByteBuf buf) {
if (buf.readableBytes() < 8) {
return false;
}
int dataCrc = buf.readInt();
int readCrc = (int) crc.getValue() & 0xffff;
if (dataCrc != readCrc) {
throw new CompressionException(
"Data CRC value missmatch. Expected: " + dataCrc + ", Got: " + readCrc);
}
int dataLength = buf.readInt();
int readLength = inflater.getTotalOut();
if (dataLength != readLength) {
throw new CompressionException(
"Number of bytes missmatch. Expected: " + dataLength + ", Got: " + readLength);
}
return true;
}
}

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@ -79,15 +79,32 @@ public final class ZlibCodecFactory {
} }
public static ZlibDecoder newZlibDecoder() { public static ZlibDecoder newZlibDecoder() {
if (PlatformDependent.javaVersion() < 7) {
return new JZlibDecoder(); return new JZlibDecoder();
} else {
return new JdkZlibDecoder();
}
} }
public static ZlibDecoder newZlibDecoder(ZlibWrapper wrapper) { public static ZlibDecoder newZlibDecoder(ZlibWrapper wrapper) {
switch (wrapper) {
case ZLIB_OR_NONE:
return new JZlibDecoder(wrapper); return new JZlibDecoder(wrapper);
default:
if (PlatformDependent.javaVersion() < 7) {
return new JZlibDecoder(wrapper);
} else {
return new JdkZlibDecoder(wrapper);
}
}
} }
public static ZlibDecoder newZlibDecoder(byte[] dictionary) { public static ZlibDecoder newZlibDecoder(byte[] dictionary) {
if (PlatformDependent.javaVersion() < 7) {
return new JZlibDecoder(dictionary); return new JZlibDecoder(dictionary);
} else {
return new JdkZlibDecoder(dictionary);
}
} }
private ZlibCodecFactory() { private ZlibCodecFactory() {

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@ -18,6 +18,7 @@ package io.netty.handler.codec.compression;
import io.netty.buffer.ByteBuf; import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled; import io.netty.buffer.Unpooled;
import io.netty.channel.embedded.EmbeddedChannel; import io.netty.channel.embedded.EmbeddedChannel;
import io.netty.util.CharsetUtil;
import org.junit.Test; import org.junit.Test;
import static org.junit.Assert.*; import static org.junit.Assert.*;
@ -26,7 +27,7 @@ public class JZlibTest {
@Test @Test
public void testZLIB() throws Exception { public void testZLIB() throws Exception {
ByteBuf data = Unpooled.wrappedBuffer("test".getBytes()); ByteBuf data = Unpooled.copiedBuffer("test", CharsetUtil.UTF_8);
EmbeddedChannel chEncoder = new EmbeddedChannel(new JZlibEncoder(ZlibWrapper.ZLIB)); EmbeddedChannel chEncoder = new EmbeddedChannel(new JZlibEncoder(ZlibWrapper.ZLIB));
@ -52,7 +53,7 @@ public class JZlibTest {
@Test @Test
public void testNONE() throws Exception { public void testNONE() throws Exception {
ByteBuf data = Unpooled.wrappedBuffer("test".getBytes()); ByteBuf data = Unpooled.copiedBuffer("test", CharsetUtil.UTF_8);
EmbeddedChannel chEncoder = new EmbeddedChannel(new JZlibEncoder(ZlibWrapper.NONE)); EmbeddedChannel chEncoder = new EmbeddedChannel(new JZlibEncoder(ZlibWrapper.NONE));
@ -79,7 +80,7 @@ public class JZlibTest {
@Test @Test
public void testGZIP() throws Exception { public void testGZIP() throws Exception {
ByteBuf data = Unpooled.wrappedBuffer("test".getBytes()); ByteBuf data = Unpooled.copiedBuffer("test", CharsetUtil.UTF_8);
EmbeddedChannel chEncoder = new EmbeddedChannel(new JZlibEncoder(ZlibWrapper.GZIP)); EmbeddedChannel chEncoder = new EmbeddedChannel(new JZlibEncoder(ZlibWrapper.GZIP));

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@ -0,0 +1,90 @@
/*
* Copyright 2013 The Netty Project
*
* The Netty Project 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 io.netty.handler.codec.compression;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.embedded.EmbeddedChannel;
import io.netty.util.CharsetUtil;
import org.junit.Test;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;
public class JdkZlibTest {
@Test
public void testZLIB() throws Exception {
ByteBuf data = Unpooled.copiedBuffer("test", CharsetUtil.UTF_8);
EmbeddedChannel chEncoder = new EmbeddedChannel(new JdkZlibEncoder(ZlibWrapper.ZLIB));
chEncoder.writeOutbound(data.copy());
assertTrue(chEncoder.finish());
ByteBuf deflatedData = (ByteBuf) chEncoder.readOutbound();
EmbeddedChannel chDecoderZlib = new EmbeddedChannel(new JdkZlibDecoder(ZlibWrapper.ZLIB));
chDecoderZlib.writeInbound(deflatedData.copy());
assertTrue(chDecoderZlib.finish());
assertEquals(data, chDecoderZlib.readInbound());
}
@Test
public void testNONE() throws Exception {
ByteBuf data = Unpooled.copiedBuffer("test", CharsetUtil.UTF_8);
EmbeddedChannel chEncoder = new EmbeddedChannel(new JdkZlibEncoder(ZlibWrapper.NONE));
chEncoder.writeOutbound(data.copy());
assertTrue(chEncoder.finish());
ByteBuf deflatedData = (ByteBuf) chEncoder.readOutbound();
EmbeddedChannel chDecoderZlibNone = new EmbeddedChannel(new JdkZlibDecoder(ZlibWrapper.NONE));
chDecoderZlibNone.writeInbound(deflatedData.copy());
assertTrue(chDecoderZlibNone.finish());
assertEquals(data, chDecoderZlibNone.readInbound());
}
@Test(expected = IllegalArgumentException.class)
public void testZLIB_OR_NONE() throws Exception {
new JdkZlibDecoder(ZlibWrapper.ZLIB_OR_NONE);
}
@Test
public void testGZIP() throws Exception {
ByteBuf data = Unpooled.copiedBuffer("test", CharsetUtil.UTF_8);
EmbeddedChannel chEncoder = new EmbeddedChannel(new JdkZlibEncoder(ZlibWrapper.GZIP));
chEncoder.writeOutbound(data.copy());
assertTrue(chEncoder.finish());
ByteBuf deflatedData = (ByteBuf) chEncoder.readOutbound();
EmbeddedChannel chDecoderGZip = new EmbeddedChannel(new JdkZlibDecoder(ZlibWrapper.GZIP));
chDecoderGZip.writeInbound(deflatedData.copy());
assertTrue(chDecoderGZip.finish());
assertEquals(data, chDecoderGZip.readInbound());
}
}