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/**
* 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.fs;
import java.io.File;
import java.io.IOException;
import java.net.URI;
import java.util.Random;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.conf.Configuration;
/****************************************************************
* Implement the FileSystem API for the checksumed local filesystem.
*
*****************************************************************/
@InterfaceAudience.Public
@InterfaceStability.Stable
public class LocalFileSystem extends ChecksumFileSystem {
static final URI NAME = URI.create("file:///");
static private Random rand = new Random();
public LocalFileSystem() {
this(new RawLocalFileSystem());
}
@Override
public void initialize(URI name, Configuration conf) throws IOException {
if (fs.getConf() == null) {
fs.initialize(name, conf);
}
String scheme = name.getScheme();
if (!scheme.equals(fs.getUri().getScheme())) {
swapScheme = scheme;
}
}
/**
* Return the protocol scheme for the FileSystem.
*
*
* @return file
*/
@Override
public String getScheme() {
return "file";
}
public FileSystem getRaw() {
return getRawFileSystem();
}
public LocalFileSystem(FileSystem rawLocalFileSystem) {
super(rawLocalFileSystem);
}
/** Convert a path to a File. */
public File pathToFile(Path path) {
return ((RawLocalFileSystem)fs).pathToFile(path);
}
@Override
public void copyFromLocalFile(boolean delSrc, Path src, Path dst)
throws IOException {
FileUtil.copy(this, src, this, dst, delSrc, getConf());
}
@Override
public void copyToLocalFile(boolean delSrc, Path src, Path dst)
throws IOException {
FileUtil.copy(this, src, this, dst, delSrc, getConf());
}
/**
* Moves files to a bad file directory on the same device, so that their
* storage will not be reused.
*/
@Override
public boolean reportChecksumFailure(Path p, FSDataInputStream in,
long inPos,
FSDataInputStream sums, long sumsPos) {
try {
// canonicalize f
File f = ((RawLocalFileSystem)fs).pathToFile(p).getCanonicalFile();
// find highest writable parent dir of f on the same device
String device = new DF(f, getConf()).getMount();
File parent = f.getParentFile();
File dir = null;
while (parent != null && FileUtil.canWrite(parent) &&
parent.toString().startsWith(device)) {
dir = parent;
parent = parent.getParentFile();
}
if (dir==null) {
throw new IOException(
"not able to find the highest writable parent dir");
}
// move the file there
File badDir = new File(dir, "bad_files");
if (!badDir.mkdirs()) {
if (!badDir.isDirectory()) {
throw new IOException("Mkdirs failed to create " + badDir.toString());
}
}
String suffix = "." + rand.nextInt();
File badFile = new File(badDir, f.getName()+suffix);
LOG.warn("Moving bad file " + f + " to " + badFile);
in.close(); // close it first
boolean b = f.renameTo(badFile); // rename it
if (!b) {
LOG.warn("Ignoring failure of renameTo");
}
// move checksum file too
File checkFile = ((RawLocalFileSystem)fs).pathToFile(getChecksumFile(p));
// close the stream before rename to release the file handle
sums.close();
b = checkFile.renameTo(new File(badDir, checkFile.getName()+suffix));
if (!b) {
LOG.warn("Ignoring failure of renameTo");
}
} catch (IOException e) {
LOG.warn("Error moving bad file " + p + ": " + e);
}
return false;
}
@Override
public boolean supportsSymlinks() {
return true;
}
@Override
public void createSymlink(Path target, Path link, boolean createParent)
throws IOException {
fs.createSymlink(target, link, createParent);
}
@Override
public FileStatus getFileLinkStatus(final Path f) throws IOException {
return fs.getFileLinkStatus(f);
}
@Override
public Path getLinkTarget(Path f) throws IOException {
return fs.getLinkTarget(f);
}
}