/**
* 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.hive.ql.io.orc;
import org.apache.hadoop.hive.shims.HadoopShims.DirectDecompressorShim;
import org.apache.hadoop.hive.shims.ShimLoader;
import org.apache.hadoop.hive.shims.HadoopShims.DirectCompressionType;
import org.iq80.snappy.Snappy;
import java.io.IOException;
import java.nio.ByteBuffer;
class SnappyCodec implements CompressionCodec, DirectDecompressionCodec {
Boolean direct = null;
@Override
public boolean compress(ByteBuffer in, ByteBuffer out,
ByteBuffer overflow) throws IOException {
int inBytes = in.remaining();
// I should work on a patch for Snappy to support an overflow buffer
// to prevent the extra buffer copy.
byte[] compressed = new byte[Snappy.maxCompressedLength(inBytes)];
int outBytes =
Snappy.compress(in.array(), in.arrayOffset() + in.position(), inBytes,
compressed, 0);
if (outBytes < inBytes) {
int remaining = out.remaining();
if (remaining >= outBytes) {
System.arraycopy(compressed, 0, out.array(), out.arrayOffset() +
out.position(), outBytes);
out.position(out.position() + outBytes);
} else {
System.arraycopy(compressed, 0, out.array(), out.arrayOffset() +
out.position(), remaining);
out.position(out.limit());
System.arraycopy(compressed, remaining, overflow.array(),
overflow.arrayOffset(), outBytes - remaining);
overflow.position(outBytes - remaining);
}
return true;
} else {
return false;
}
}
@Override
public void decompress(ByteBuffer in, ByteBuffer out) throws IOException {
if(in.isDirect() && out.isDirect()) {
directDecompress(in, out);
return;
}
int inOffset = in.position();
int uncompressLen =
Snappy.uncompress(in.array(), in.arrayOffset() + inOffset,
in.limit() - inOffset, out.array(), out.arrayOffset() + out.position());
out.position(uncompressLen + out.position());
out.flip();
}
@Override
public boolean isAvailable() {
if (direct == null) {
try {
if (ShimLoader.getHadoopShims().getDirectDecompressor(
DirectCompressionType.SNAPPY) != null) {
direct = Boolean.valueOf(true);
} else {
direct = Boolean.valueOf(false);
}
} catch (UnsatisfiedLinkError ule) {
direct = Boolean.valueOf(false);
}
}
return direct.booleanValue();
}
@Override
public void directDecompress(ByteBuffer in, ByteBuffer out)
throws IOException {
DirectDecompressorShim decompressShim = ShimLoader.getHadoopShims()
.getDirectDecompressor(DirectCompressionType.SNAPPY);
decompressShim.decompress(in, out);
out.flip(); // flip for read
}
}