/*
* 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.commons.compress.archivers.sevenz;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import org.tukaani.xz.FinishableWrapperOutputStream;
import org.tukaani.xz.FinishableOutputStream;
import org.tukaani.xz.LZMA2InputStream;
import org.tukaani.xz.LZMA2Options;
class LZMA2Decoder extends CoderBase {
LZMA2Decoder() {
super(LZMA2Options.class, Number.class);
}
@Override
InputStream decode(final InputStream in, final Coder coder, byte[] password) throws IOException {
try {
int dictionarySize = getDictionarySize(coder);
return new LZMA2InputStream(in, dictionarySize);
} catch (IllegalArgumentException ex) {
throw new IOException(ex.getMessage());
}
}
@Override
OutputStream encode(final OutputStream out, final Object opts)
throws IOException {
LZMA2Options options = getOptions(opts);
FinishableOutputStream wrapped = new FinishableWrapperOutputStream(out);
return options.getOutputStream(wrapped);
}
@Override
byte[] getOptionsAsProperties(Object opts) {
int dictSize = getDictSize(opts);
int lead = Integer.numberOfLeadingZeros(dictSize);
int secondBit = (dictSize >>> (30 - lead)) - 2;
return new byte[] {
(byte) ((19 - lead) * 2 + secondBit)
};
}
@Override
Object getOptionsFromCoder(Coder coder, InputStream in) {
return Integer.valueOf(getDictionarySize(coder));
}
private int getDictSize(Object opts) {
if (opts instanceof LZMA2Options) {
return ((LZMA2Options) opts).getDictSize();
}
return numberOptionOrDefault(opts);
}
private int getDictionarySize(Coder coder) throws IllegalArgumentException {
final int dictionarySizeBits = 0xff & coder.properties[0];
if ((dictionarySizeBits & (~0x3f)) != 0) {
throw new IllegalArgumentException("Unsupported LZMA2 property bits");
}
if (dictionarySizeBits > 40) {
throw new IllegalArgumentException("Dictionary larger than 4GiB maximum size");
}
if (dictionarySizeBits == 40) {
return 0xFFFFffff;
}
return (2 | (dictionarySizeBits & 0x1)) << (dictionarySizeBits / 2 + 11);
}
private LZMA2Options getOptions(Object opts) throws IOException {
if (opts instanceof LZMA2Options) {
return (LZMA2Options) opts;
}
LZMA2Options options = new LZMA2Options();
options.setDictSize(numberOptionOrDefault(opts));
return options;
}
private int numberOptionOrDefault(Object opts) {
return numberOptionOrDefault(opts, LZMA2Options.DICT_SIZE_DEFAULT);
}
}