| /* |
| * 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.cassandra.io.util; |
| |
| import java.io.*; |
| import java.nio.ByteBuffer; |
| import java.nio.charset.StandardCharsets; |
| import java.util.zip.CRC32; |
| |
| import javax.annotation.Nonnull; |
| |
| import org.apache.cassandra.io.FSWriteError; |
| |
| public class ChecksumWriter |
| { |
| private final CRC32 incrementalChecksum = new CRC32(); |
| private final DataOutput incrementalOut; |
| private final CRC32 fullChecksum = new CRC32(); |
| |
| public ChecksumWriter(DataOutput incrementalOut) |
| { |
| this.incrementalOut = incrementalOut; |
| } |
| |
| public void writeChunkSize(int length) |
| { |
| try |
| { |
| incrementalOut.writeInt(length); |
| } |
| catch (IOException e) |
| { |
| throw new IOError(e); |
| } |
| } |
| |
| // checksumIncrementalResult indicates if the checksum we compute for this buffer should itself be |
| // included in the full checksum, translating to if the partial checksum is serialized along with the |
| // data it checksums (in which case the file checksum as calculated by external tools would mismatch if |
| // we did not include it), or independently. |
| |
| // CompressedSequentialWriters serialize the partial checksums inline with the compressed data chunks they |
| // corroborate, whereas ChecksummedSequentialWriters serialize them to a different file. |
| public void appendDirect(ByteBuffer bb, boolean checksumIncrementalResult) |
| { |
| try |
| { |
| ByteBuffer toAppend = bb.duplicate(); |
| toAppend.mark(); |
| incrementalChecksum.update(toAppend); |
| toAppend.reset(); |
| |
| int incrementalChecksumValue = (int) incrementalChecksum.getValue(); |
| incrementalOut.writeInt(incrementalChecksumValue); |
| |
| fullChecksum.update(toAppend); |
| if (checksumIncrementalResult) |
| { |
| ByteBuffer byteBuffer = ByteBuffer.allocate(4); |
| byteBuffer.putInt(incrementalChecksumValue); |
| assert byteBuffer.arrayOffset() == 0; |
| fullChecksum.update(byteBuffer.array(), 0, byteBuffer.array().length); |
| } |
| incrementalChecksum.reset(); |
| |
| } |
| catch (IOException e) |
| { |
| throw new IOError(e); |
| } |
| } |
| |
| public void writeFullChecksum(@Nonnull File digestFile) |
| { |
| try (FileOutputStream fos = new FileOutputStream(digestFile); |
| DataOutputStream out = new DataOutputStream(new BufferedOutputStream(fos))) |
| { |
| out.write(String.valueOf(fullChecksum.getValue()).getBytes(StandardCharsets.UTF_8)); |
| out.flush(); |
| fos.getFD().sync(); |
| } |
| catch (IOException e) |
| { |
| throw new FSWriteError(e, digestFile); |
| } |
| } |
| } |
| |