/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF 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 org.apache.hadoop.io.compress.lzma;
import java.io.IOException;
import java.nio.Buffer;
import java.nio.ByteBuffer;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.io.compress.Decompressor;
import org.apache.hadoop.util.NativeCodeLoader;
/**
* A {@link Decompressor} based on the popular
* lzma compression algorithm.
* http://www.7zip.org/
*
*/
public class LzmaDecompressor implements Decompressor {
private static final Log LOG =
LogFactory.getLog(LzmaCompressor.class.getName());
private static final int DEFAULT_DIRECT_BUFFER_SIZE = 64*1024;
// HACK - Use this as a global lock in the JNI layer
private static Class clazz = LzmaDecompressor.class;
private long stream;
private int directBufferSize;
private Buffer compressedDirectBuf = null;
private int compressedDirectBufOff, compressedDirectBufLen;
private Buffer uncompressedDirectBuf = null;
private byte[] userBuf = null;
private int userBufOff = 0, userBufLen = 0;
private boolean finished;
private static boolean nativeLzmaLoaded = false;
static {
if (NativeCodeLoader.isNativeCodeLoaded()) {
try {
// Initialize the native library
initIDs();
nativeLzmaLoaded = true;
} catch (Throwable t) {
// Ignore failure to load/initialize native-lzma
LOG.error("calling initIDs() failed in LzmaDecompressor...");
nativeLzmaLoaded = false;
}
}else {
LOG.error("Cannot load " + LzmaCompressor.class.getName() +
" without native-hadoop library!");
nativeLzmaLoaded = false;
}
}
public static boolean isNativeLzmaLoaded() {
return nativeLzmaLoaded;
}
/**
* Creates a new decompressor.
*/
public LzmaDecompressor(int directBufferSize) {
this.directBufferSize = directBufferSize;
compressedDirectBuf = ByteBuffer.allocateDirect(directBufferSize);
uncompressedDirectBuf = ByteBuffer.allocateDirect(directBufferSize);
uncompressedDirectBuf.position(directBufferSize);
stream = init();
}
public LzmaDecompressor() {
this(DEFAULT_DIRECT_BUFFER_SIZE);
}
public synchronized void setInput(byte[] b, int off, int len) {
if (b == null) {
throw new NullPointerException();
}
if (off < 0 || len < 0 || off > b.length - len) {
throw new ArrayIndexOutOfBoundsException();
}
this.userBuf = b;
this.userBufOff = off;
this.userBufLen = len;
setInputFromSavedData();
// Reinitialize lzma's output direct buffer
uncompressedDirectBuf.limit(directBufferSize);
uncompressedDirectBuf.position(directBufferSize);
}
synchronized void setInputFromSavedData() {
compressedDirectBufOff = 0;
compressedDirectBufLen = userBufLen;
if (compressedDirectBufLen > directBufferSize) {
compressedDirectBufLen = directBufferSize;
}
// Reinitialize lzma's input direct buffer
compressedDirectBuf.rewind();
((ByteBuffer)compressedDirectBuf).put(userBuf, userBufOff,
compressedDirectBufLen);
// Note how much data is being fed to lzma
userBufOff += compressedDirectBufLen;
userBufLen -= compressedDirectBufLen;
}
public synchronized void setDictionary(byte[] b, int off, int len) {
// nop
}
public synchronized boolean needsInput() {
// Consume remanining compressed data?
if (uncompressedDirectBuf.remaining() > 0) {
return false;
}
// Check if lzma has consumed all input
if (compressedDirectBufLen <= 0) {
// Check if we have consumed all user-input
if (userBufLen <= 0) {
return true;
} else {
setInputFromSavedData();
}
}
return false;
}
public synchronized boolean needsDictionary() {
return false;
}
public synchronized boolean finished() {
// Check if 'lzma' says its 'finished' and
// all compressed data has been consumed
return (finished && uncompressedDirectBuf.remaining() == 0);
}
public synchronized int decompress(byte[] b, int off, int len)
throws IOException {
if (b == null) {
throw new NullPointerException();
}
if (off < 0 || len < 0 || off > b.length - len) {
throw new ArrayIndexOutOfBoundsException();
}
int n = 0;
// Check if there is uncompressed data
n = uncompressedDirectBuf.remaining();
if (n > 0) {
n = Math.min(n, len);
((ByteBuffer)uncompressedDirectBuf).get(b, off, n);
return n;
}
// Re-initialize the lzma's output direct buffer
uncompressedDirectBuf.rewind();
uncompressedDirectBuf.limit(directBufferSize);
// Decompress data
if(compressedDirectBufLen > 0) {
n = decompressBytesDirect();
}
uncompressedDirectBuf.limit(n);
// Get atmost 'len' bytes
n = Math.min(n, len);
((ByteBuffer)uncompressedDirectBuf).get(b, off, n);
return n;
}
/**
* Returns the total number of compressed bytes output so far.
*
* @return the total (non-negative) number of compressed bytes output so far
*/
public synchronized long getBytesWritten() {
checkStream();
return getBytesWritten(stream);
}
/**
* Returns the total number of uncompressed bytes input so far.</p>
*
* @return the total (non-negative) number of uncompressed bytes input so far
*/
public synchronized long getBytesRead() {
checkStream();
return getBytesRead(stream);
}
public synchronized void reset() {
checkStream();
finished = false;
compressedDirectBufOff = compressedDirectBufLen = 0;
uncompressedDirectBuf.limit(directBufferSize);
uncompressedDirectBuf.position(directBufferSize);
userBufOff = userBufLen = 0;
end();
stream = init();
}
public synchronized void end() {
if (stream != 0) {
end(stream);
stream = 0;
}
}
protected void finalize() {
end();
}
private void checkStream() {
if (stream == 0)
throw new NullPointerException();
}
private native static void initIDs();
private native static long init();
private native int decompressBytesDirect();
private native static long getBytesRead(long strm);
private native static long getBytesWritten(long strm);
private native static void end(long strm);
}