001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018package org.apache.commons.compress.compressors.zstandard;
019
020
021import java.io.IOException;
022import java.io.InputStream;
023
024import org.apache.commons.compress.compressors.CompressorInputStream;
025import org.apache.commons.compress.utils.CountingInputStream;
026import org.apache.commons.compress.utils.IOUtils;
027import org.apache.commons.compress.utils.InputStreamStatistics;
028
029import com.github.luben.zstd.BufferPool;
030import com.github.luben.zstd.ZstdInputStream;
031
032/**
033 * {@link CompressorInputStream} implementation to decode Zstandard encoded stream.
034 * Library relies on <a href="https://github.com/luben/zstd-jni/">Zstandard JNI</a>
035 *
036 * @since 1.16
037 */
038public class ZstdCompressorInputStream extends CompressorInputStream
039    implements InputStreamStatistics {
040
041    private final CountingInputStream countingStream;
042    private final ZstdInputStream decIS;
043
044    public ZstdCompressorInputStream(final InputStream in) throws IOException {
045        this.decIS = new ZstdInputStream(countingStream = new CountingInputStream(in));
046    }
047
048    /**
049     * Creates a new input stream that decompresses zstd-compressed data from
050     * the specific input stream
051     *
052     * @param in the input stream of compressed data
053     * @param bufferPool a configuration of zstd-jni that allows users to customize
054     *                   how buffers are recycled. Either a
055     *                   {@link com.github.luben.zstd.NoPool} or a
056     *                   {@link com.github.luben.zstd.RecyclingBufferPool} is
057     *                   allowed here.
058     * @throws IOException if an IO error occurs.
059     */
060    public ZstdCompressorInputStream(final InputStream in, final BufferPool bufferPool) throws IOException {
061        this.decIS = new ZstdInputStream(countingStream = new CountingInputStream(in), bufferPool);
062    }
063
064    @Override
065    public int available() throws IOException {
066        return decIS.available();
067    }
068
069    @Override
070    public void close() throws IOException {
071        decIS.close();
072    }
073
074    /**
075     * @since 1.17
076     */
077    @Override
078    public long getCompressedCount() {
079        return countingStream.getBytesRead();
080    }
081
082    @Override
083    public synchronized void mark(final int readlimit) {
084        decIS.mark(readlimit);
085    }
086
087    @Override
088    public boolean markSupported() {
089        return decIS.markSupported();
090    }
091
092    @Override
093    public int read() throws IOException {
094        final int ret = decIS.read();
095        count(ret == -1 ? 0 : 1);
096        return ret;
097    }
098
099    @Override
100    public int read(final byte[] b) throws IOException {
101        return read(b, 0, b.length);
102    }
103
104    @Override
105    public int read(final byte[] buf, final int off, final int len) throws IOException {
106        if (len == 0) {
107            return 0;
108        }
109        final int ret = decIS.read(buf, off, len);
110        count(ret);
111        return ret;
112    }
113
114    @Override
115    public synchronized void reset() throws IOException {
116        decIS.reset();
117    }
118
119    @Override
120    public long skip(final long n) throws IOException {
121        return IOUtils.skip(decIS, n);
122    }
123
124    @Override
125    public String toString() {
126        return decIS.toString();
127    }
128}