001 /**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements. See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership. The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License. You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018
019 package org.apache.hadoop.fs;
020
021 import java.io.File;
022 import java.io.IOException;
023 import java.net.URI;
024 import java.util.Random;
025
026 import org.apache.hadoop.classification.InterfaceAudience;
027 import org.apache.hadoop.classification.InterfaceStability;
028 import org.apache.hadoop.conf.Configuration;
029
030 /****************************************************************
031 * Implement the FileSystem API for the checksumed local filesystem.
032 *
033 *****************************************************************/
034 @InterfaceAudience.Public
035 @InterfaceStability.Stable
036 public class LocalFileSystem extends ChecksumFileSystem {
037 static final URI NAME = URI.create("file:///");
038 static private Random rand = new Random();
039
040 public LocalFileSystem() {
041 this(new RawLocalFileSystem());
042 }
043
044 @Override
045 public void initialize(URI name, Configuration conf) throws IOException {
046 if (fs.getConf() == null) {
047 fs.initialize(name, conf);
048 }
049 String scheme = name.getScheme();
050 if (!scheme.equals(fs.getUri().getScheme())) {
051 swapScheme = scheme;
052 }
053 }
054
055 /**
056 * Return the protocol scheme for the FileSystem.
057 * <p/>
058 *
059 * @return <code>file</code>
060 */
061 @Override
062 public String getScheme() {
063 return "file";
064 }
065
066 public FileSystem getRaw() {
067 return getRawFileSystem();
068 }
069
070 public LocalFileSystem(FileSystem rawLocalFileSystem) {
071 super(rawLocalFileSystem);
072 }
073
074 /** Convert a path to a File. */
075 public File pathToFile(Path path) {
076 return ((RawLocalFileSystem)fs).pathToFile(path);
077 }
078
079 @Override
080 public void copyFromLocalFile(boolean delSrc, Path src, Path dst)
081 throws IOException {
082 FileUtil.copy(this, src, this, dst, delSrc, getConf());
083 }
084
085 @Override
086 public void copyToLocalFile(boolean delSrc, Path src, Path dst)
087 throws IOException {
088 FileUtil.copy(this, src, this, dst, delSrc, getConf());
089 }
090
091 /**
092 * Moves files to a bad file directory on the same device, so that their
093 * storage will not be reused.
094 */
095 @Override
096 public boolean reportChecksumFailure(Path p, FSDataInputStream in,
097 long inPos,
098 FSDataInputStream sums, long sumsPos) {
099 try {
100 // canonicalize f
101 File f = ((RawLocalFileSystem)fs).pathToFile(p).getCanonicalFile();
102
103 // find highest writable parent dir of f on the same device
104 String device = new DF(f, getConf()).getMount();
105 File parent = f.getParentFile();
106 File dir = null;
107 while (parent != null && FileUtil.canWrite(parent) &&
108 parent.toString().startsWith(device)) {
109 dir = parent;
110 parent = parent.getParentFile();
111 }
112
113 if (dir==null) {
114 throw new IOException(
115 "not able to find the highest writable parent dir");
116 }
117
118 // move the file there
119 File badDir = new File(dir, "bad_files");
120 if (!badDir.mkdirs()) {
121 if (!badDir.isDirectory()) {
122 throw new IOException("Mkdirs failed to create " + badDir.toString());
123 }
124 }
125 String suffix = "." + rand.nextInt();
126 File badFile = new File(badDir, f.getName()+suffix);
127 LOG.warn("Moving bad file " + f + " to " + badFile);
128 in.close(); // close it first
129 boolean b = f.renameTo(badFile); // rename it
130 if (!b) {
131 LOG.warn("Ignoring failure of renameTo");
132 }
133 // move checksum file too
134 File checkFile = ((RawLocalFileSystem)fs).pathToFile(getChecksumFile(p));
135 // close the stream before rename to release the file handle
136 sums.close();
137 b = checkFile.renameTo(new File(badDir, checkFile.getName()+suffix));
138 if (!b) {
139 LOG.warn("Ignoring failure of renameTo");
140 }
141 } catch (IOException e) {
142 LOG.warn("Error moving bad file " + p + ": " + e);
143 }
144 return false;
145 }
146
147 @Override
148 public boolean supportsSymlinks() {
149 return true;
150 }
151
152 @Override
153 public void createSymlink(Path target, Path link, boolean createParent)
154 throws IOException {
155 fs.createSymlink(target, link, createParent);
156 }
157
158 @Override
159 public FileStatus getFileLinkStatus(final Path f) throws IOException {
160 return fs.getFileLinkStatus(f);
161 }
162
163 @Override
164 public Path getLinkTarget(Path f) throws IOException {
165 return fs.getLinkTarget(f);
166 }
167 }