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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 io.prestosql.hadoop.$internal.com.google.common.annotations.VisibleForTesting;
import java.io.BufferedOutputStream;
import java.io.DataOutput;
import java.io.EOFException;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.FileDescriptor;
import java.net.URI;
import java.nio.ByteBuffer;
import java.nio.file.Files;
import java.nio.file.NoSuchFileException;
import java.nio.file.attribute.BasicFileAttributes;
import java.nio.file.attribute.BasicFileAttributeView;
import java.nio.file.attribute.FileTime;
import java.util.Arrays;
import java.util.EnumSet;
import java.util.Optional;
import java.util.StringTokenizer;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.permission.FsPermission;
import org.apache.hadoop.io.IOUtils;
import org.apache.hadoop.io.nativeio.NativeIO;
import org.apache.hadoop.util.Progressable;
import org.apache.hadoop.util.Shell;
import org.apache.hadoop.util.StringUtils;
/****************************************************************
* Implement the FileSystem API for the raw local filesystem.
*
*****************************************************************/
@InterfaceAudience.Public
@InterfaceStability.Stable
public class RawLocalFileSystem extends FileSystem {
static final URI NAME = URI.create("file:///");
private Path workingDir;
// Temporary workaround for HADOOP-9652.
private static boolean useDeprecatedFileStatus = true;
@VisibleForTesting
public static void useStatIfAvailable() {
useDeprecatedFileStatus = !Stat.isAvailable();
}
public RawLocalFileSystem() {
workingDir = getInitialWorkingDirectory();
}
private Path makeAbsolute(Path f) {
if (f.isAbsolute()) {
return f;
} else {
return new Path(workingDir, f);
}
}
/** Convert a path to a File. */
public File pathToFile(Path path) {
checkPath(path);
if (!path.isAbsolute()) {
path = new Path(getWorkingDirectory(), path);
}
return new File(path.toUri().getPath());
}
@Override
public URI getUri() { return NAME; }
@Override
public void initialize(URI uri, Configuration conf) throws IOException {
super.initialize(uri, conf);
setConf(conf);
}
/*******************************************************
* For open()'s FSInputStream.
*******************************************************/
class LocalFSFileInputStream extends FSInputStream implements HasFileDescriptor {
private FileInputStream fis;
private long position;
public LocalFSFileInputStream(Path f) throws IOException {
fis = new FileInputStream(pathToFile(f));
}
@Override
public void seek(long pos) throws IOException {
if (pos < 0) {
throw new EOFException(
FSExceptionMessages.NEGATIVE_SEEK);
}
fis.getChannel().position(pos);
this.position = pos;
}
@Override
public long getPos() throws IOException {
return this.position;
}
@Override
public boolean seekToNewSource(long targetPos) throws IOException {
return false;
}
/*
* Just forward to the fis
*/
@Override
public int available() throws IOException { return fis.available(); }
@Override
public void close() throws IOException { fis.close(); }
@Override
public boolean markSupported() { return false; }
@Override
public int read() throws IOException {
try {
int value = fis.read();
if (value >= 0) {
this.position++;
statistics.incrementBytesRead(1);
}
return value;
} catch (IOException e) { // unexpected exception
throw new FSError(e); // assume native fs error
}
}
@Override
public int read(byte[] b, int off, int len) throws IOException {
// parameter check
validatePositionedReadArgs(position, b, off, len);
try {
int value = fis.read(b, off, len);
if (value > 0) {
this.position += value;
statistics.incrementBytesRead(value);
}
return value;
} catch (IOException e) { // unexpected exception
throw new FSError(e); // assume native fs error
}
}
@Override
public int read(long position, byte[] b, int off, int len)
throws IOException {
// parameter check
validatePositionedReadArgs(position, b, off, len);
if (len == 0) {
return 0;
}
ByteBuffer bb = ByteBuffer.wrap(b, off, len);
try {
int value = fis.getChannel().read(bb, position);
if (value > 0) {
statistics.incrementBytesRead(value);
}
return value;
} catch (IOException e) {
throw new FSError(e);
}
}
@Override
public long skip(long n) throws IOException {
long value = fis.skip(n);
if (value > 0) {
this.position += value;
}
return value;
}
@Override
public FileDescriptor getFileDescriptor() throws IOException {
return fis.getFD();
}
}
@Override
public FSDataInputStream open(Path f, int bufferSize) throws IOException {
getFileStatus(f);
return new FSDataInputStream(new BufferedFSInputStream(
new LocalFSFileInputStream(f), bufferSize));
}
@Override
public FSDataInputStream open(PathHandle fd, int bufferSize)
throws IOException {
if (!(fd instanceof LocalFileSystemPathHandle)) {
fd = new LocalFileSystemPathHandle(fd.bytes());
}
LocalFileSystemPathHandle id = (LocalFileSystemPathHandle) fd;
id.verify(getFileStatus(new Path(id.getPath())));
return new FSDataInputStream(new BufferedFSInputStream(
new LocalFSFileInputStream(new Path(id.getPath())), bufferSize));
}
/*********************************************************
* For create()'s FSOutputStream.
*********************************************************/
class LocalFSFileOutputStream extends OutputStream {
private FileOutputStream fos;
private LocalFSFileOutputStream(Path f, boolean append,
FsPermission permission) throws IOException {
File file = pathToFile(f);
if (!append && permission == null) {
permission = FsPermission.getFileDefault();
}
if (permission == null) {
this.fos = new FileOutputStream(file, append);
} else {
permission = permission.applyUMask(FsPermission.getUMask(getConf()));
if (Shell.WINDOWS && NativeIO.isAvailable()) {
this.fos = NativeIO.Windows.createFileOutputStreamWithMode(file,
append, permission.toShort());
} else {
this.fos = new FileOutputStream(file, append);
boolean success = false;
try {
setPermission(f, permission);
success = true;
} finally {
if (!success) {
IOUtils.cleanup(LOG, this.fos);
}
}
}
}
}
/*
* Just forward to the fos
*/
@Override
public void close() throws IOException { fos.close(); }
@Override
public void flush() throws IOException { fos.flush(); }
@Override
public void write(byte[] b, int off, int len) throws IOException {
try {
fos.write(b, off, len);
} catch (IOException e) { // unexpected exception
throw new FSError(e); // assume native fs error
}
}
@Override
public void write(int b) throws IOException {
try {
fos.write(b);
} catch (IOException e) { // unexpected exception
throw new FSError(e); // assume native fs error
}
}
}
@Override
public FSDataOutputStream append(Path f, int bufferSize,
Progressable progress) throws IOException {
FileStatus status = getFileStatus(f);
if (status.isDirectory()) {
throw new IOException("Cannot append to a diretory (=" + f + " )");
}
return new FSDataOutputStream(new BufferedOutputStream(
createOutputStreamWithMode(f, true, null), bufferSize), statistics,
status.getLen());
}
@Override
public FSDataOutputStream create(Path f, boolean overwrite, int bufferSize,
short replication, long blockSize, Progressable progress)
throws IOException {
return create(f, overwrite, true, bufferSize, replication, blockSize,
progress, null);
}
private FSDataOutputStream create(Path f, boolean overwrite,
boolean createParent, int bufferSize, short replication, long blockSize,
Progressable progress, FsPermission permission) throws IOException {
if (exists(f) && !overwrite) {
throw new FileAlreadyExistsException("File already exists: " + f);
}
Path parent = f.getParent();
if (parent != null && !mkdirs(parent)) {
throw new IOException("Mkdirs failed to create " + parent.toString());
}
return new FSDataOutputStream(new BufferedOutputStream(
createOutputStreamWithMode(f, false, permission), bufferSize),
statistics);
}
protected OutputStream createOutputStream(Path f, boolean append)
throws IOException {
return createOutputStreamWithMode(f, append, null);
}
protected OutputStream createOutputStreamWithMode(Path f, boolean append,
FsPermission permission) throws IOException {
return new LocalFSFileOutputStream(f, append, permission);
}
@Override
public FSDataOutputStream createNonRecursive(Path f, FsPermission permission,
EnumSet flags, int bufferSize, short replication, long blockSize,
Progressable progress) throws IOException {
if (exists(f) && !flags.contains(CreateFlag.OVERWRITE)) {
throw new FileAlreadyExistsException("File already exists: " + f);
}
return new FSDataOutputStream(new BufferedOutputStream(
createOutputStreamWithMode(f, false, permission), bufferSize),
statistics);
}
@Override
public FSDataOutputStream create(Path f, FsPermission permission,
boolean overwrite, int bufferSize, short replication, long blockSize,
Progressable progress) throws IOException {
FSDataOutputStream out = create(f, overwrite, true, bufferSize, replication,
blockSize, progress, permission);
return out;
}
@Override
public FSDataOutputStream createNonRecursive(Path f, FsPermission permission,
boolean overwrite,
int bufferSize, short replication, long blockSize,
Progressable progress) throws IOException {
FSDataOutputStream out = create(f, overwrite, false, bufferSize, replication,
blockSize, progress, permission);
return out;
}
@Override
public void concat(final Path trg, final Path [] psrcs) throws IOException {
final int bufferSize = 4096;
try(FSDataOutputStream out = create(trg)) {
for (Path src : psrcs) {
try(FSDataInputStream in = open(src)) {
IOUtils.copyBytes(in, out, bufferSize, false);
}
}
}
}
@Override
public boolean rename(Path src, Path dst) throws IOException {
// Attempt rename using Java API.
File srcFile = pathToFile(src);
File dstFile = pathToFile(dst);
if (srcFile.renameTo(dstFile)) {
return true;
}
// Else try POSIX style rename on Windows only
if (Shell.WINDOWS &&
handleEmptyDstDirectoryOnWindows(src, srcFile, dst, dstFile)) {
return true;
}
// The fallback behavior accomplishes the rename by a full copy.
if (LOG.isDebugEnabled()) {
LOG.debug("Falling through to a copy of " + src + " to " + dst);
}
return FileUtil.copy(this, src, this, dst, true, getConf());
}
@VisibleForTesting
public final boolean handleEmptyDstDirectoryOnWindows(Path src, File srcFile,
Path dst, File dstFile) throws IOException {
// Enforce POSIX rename behavior that a source directory replaces an
// existing destination if the destination is an empty directory. On most
// platforms, this is already handled by the Java API call above. Some
// platforms (notably Windows) do not provide this behavior, so the Java API
// call renameTo(dstFile) fails. Delete destination and attempt rename
// again.
try {
FileStatus sdst = this.getFileStatus(dst);
String[] dstFileList = dstFile.list();
if (dstFileList != null) {
if (sdst.isDirectory() && dstFileList.length == 0) {
if (LOG.isDebugEnabled()) {
LOG.debug("Deleting empty destination and renaming " + src +
" to " + dst);
}
if (this.delete(dst, false) && srcFile.renameTo(dstFile)) {
return true;
}
}
}
} catch (FileNotFoundException ignored) {
}
return false;
}
@Override
public boolean truncate(Path f, final long newLength) throws IOException {
FileStatus status = getFileStatus(f);
if(status == null) {
throw new FileNotFoundException("File " + f + " not found");
}
if(status.isDirectory()) {
throw new IOException("Cannot truncate a directory (=" + f + ")");
}
long oldLength = status.getLen();
if(newLength > oldLength) {
throw new IllegalArgumentException(
"Cannot truncate to a larger file size. Current size: " + oldLength +
", truncate size: " + newLength + ".");
}
try (FileOutputStream out = new FileOutputStream(pathToFile(f), true)) {
try {
out.getChannel().truncate(newLength);
} catch(IOException e) {
throw new FSError(e);
}
}
return true;
}
/**
* Delete the given path to a file or directory.
* @param p the path to delete
* @param recursive to delete sub-directories
* @return true if the file or directory and all its contents were deleted
* @throws IOException if p is non-empty and recursive is false
*/
@Override
public boolean delete(Path p, boolean recursive) throws IOException {
File f = pathToFile(p);
if (!f.exists()) {
//no path, return false "nothing to delete"
return false;
}
if (f.isFile()) {
return f.delete();
} else if (!recursive && f.isDirectory() &&
(FileUtil.listFiles(f).length != 0)) {
throw new IOException("Directory " + f.toString() + " is not empty");
}
return FileUtil.fullyDelete(f);
}
/**
* {@inheritDoc}
*
* (Note: Returned list is not sorted in any given order,
* due to reliance on Java's {@link File#list()} API.)
*/
@Override
public FileStatus[] listStatus(Path f) throws IOException {
File localf = pathToFile(f);
FileStatus[] results;
if (!localf.exists()) {
throw new FileNotFoundException("File " + f + " does not exist");
}
if (localf.isDirectory()) {
String[] names = FileUtil.list(localf);
results = new FileStatus[names.length];
int j = 0;
for (int i = 0; i < names.length; i++) {
try {
// Assemble the path using the Path 3 arg constructor to make sure
// paths with colon are properly resolved on Linux
results[j] = getFileStatus(new Path(f, new Path(null, null,
names[i])));
j++;
} catch (FileNotFoundException e) {
// ignore the files not found since the dir list may have have
// changed since the names[] list was generated.
}
}
if (j == names.length) {
return results;
}
return Arrays.copyOf(results, j);
}
if (!useDeprecatedFileStatus) {
return new FileStatus[] { getFileStatus(f) };
}
return new FileStatus[] {
new DeprecatedRawLocalFileStatus(localf,
getDefaultBlockSize(f), this) };
}
protected boolean mkOneDir(File p2f) throws IOException {
return mkOneDirWithMode(new Path(p2f.getAbsolutePath()), p2f, null);
}
protected boolean mkOneDirWithMode(Path p, File p2f, FsPermission permission)
throws IOException {
if (permission == null) {
permission = FsPermission.getDirDefault();
}
permission = permission.applyUMask(FsPermission.getUMask(getConf()));
if (Shell.WINDOWS && NativeIO.isAvailable()) {
try {
NativeIO.Windows.createDirectoryWithMode(p2f, permission.toShort());
return true;
} catch (IOException e) {
if (LOG.isDebugEnabled()) {
LOG.debug(String.format(
"NativeIO.createDirectoryWithMode error, path = %s, mode = %o",
p2f, permission.toShort()), e);
}
return false;
}
} else {
boolean b = p2f.mkdir();
if (b) {
setPermission(p, permission);
}
return b;
}
}
/**
* Creates the specified directory hierarchy. Does not
* treat existence as an error.
*/
@Override
public boolean mkdirs(Path f) throws IOException {
return mkdirsWithOptionalPermission(f, null);
}
@Override
public boolean mkdirs(Path f, FsPermission permission) throws IOException {
return mkdirsWithOptionalPermission(f, permission);
}
private boolean mkdirsWithOptionalPermission(Path f, FsPermission permission)
throws IOException {
if(f == null) {
throw new IllegalArgumentException("mkdirs path arg is null");
}
Path parent = f.getParent();
File p2f = pathToFile(f);
File parent2f = null;
if(parent != null) {
parent2f = pathToFile(parent);
if(parent2f != null && parent2f.exists() && !parent2f.isDirectory()) {
throw new ParentNotDirectoryException("Parent path is not a directory: "
+ parent);
}
}
if (p2f.exists() && !p2f.isDirectory()) {
throw new FileAlreadyExistsException("Destination exists" +
" and is not a directory: " + p2f.getCanonicalPath());
}
return (parent == null || parent2f.exists() || mkdirs(parent)) &&
(mkOneDirWithMode(f, p2f, permission) || p2f.isDirectory());
}
@Override
public Path getHomeDirectory() {
return this.makeQualified(new Path(System.getProperty("user.home")));
}
/**
* Set the working directory to the given directory.
*/
@Override
public void setWorkingDirectory(Path newDir) {
workingDir = makeAbsolute(newDir);
checkPath(workingDir);
}
@Override
public Path getWorkingDirectory() {
return workingDir;
}
@Override
protected Path getInitialWorkingDirectory() {
return this.makeQualified(new Path(System.getProperty("user.dir")));
}
@Override
public FsStatus getStatus(Path p) throws IOException {
File partition = pathToFile(p == null ? new Path("/") : p);
//File provides getUsableSpace() and getFreeSpace()
//File provides no API to obtain used space, assume used = total - free
return new FsStatus(partition.getTotalSpace(),
partition.getTotalSpace() - partition.getFreeSpace(),
partition.getFreeSpace());
}
// In the case of the local filesystem, we can just rename the file.
@Override
public void moveFromLocalFile(Path src, Path dst) throws IOException {
rename(src, dst);
}
// We can write output directly to the final location
@Override
public Path startLocalOutput(Path fsOutputFile, Path tmpLocalFile)
throws IOException {
return fsOutputFile;
}
// It's in the right place - nothing to do.
@Override
public void completeLocalOutput(Path fsWorkingFile, Path tmpLocalFile)
throws IOException {
}
@Override
public void close() throws IOException {
super.close();
}
@Override
public String toString() {
return "LocalFS";
}
@Override
public FileStatus getFileStatus(Path f) throws IOException {
return getFileLinkStatusInternal(f, true);
}
@Deprecated
private FileStatus deprecatedGetFileStatus(Path f) throws IOException {
File path = pathToFile(f);
if (path.exists()) {
return new DeprecatedRawLocalFileStatus(pathToFile(f),
getDefaultBlockSize(f), this);
} else {
throw new FileNotFoundException("File " + f + " does not exist");
}
}
@Deprecated
static class DeprecatedRawLocalFileStatus extends FileStatus {
/* We can add extra fields here. It breaks at least CopyFiles.FilePair().
* We recognize if the information is already loaded by check if
* onwer.equals("").
*/
private boolean isPermissionLoaded() {
return !super.getOwner().isEmpty();
}
private static long getLastAccessTime(File f) throws IOException {
long accessTime;
try {
accessTime = Files.readAttributes(f.toPath(),
BasicFileAttributes.class).lastAccessTime().toMillis();
} catch (NoSuchFileException e) {
throw new FileNotFoundException("File " + f + " does not exist");
}
return accessTime;
}
DeprecatedRawLocalFileStatus(File f, long defaultBlockSize, FileSystem fs)
throws IOException {
super(f.length(), f.isDirectory(), 1, defaultBlockSize,
f.lastModified(), getLastAccessTime(f),
null, null, null,
new Path(f.getPath()).makeQualified(fs.getUri(),
fs.getWorkingDirectory()));
}
@Override
public FsPermission getPermission() {
if (!isPermissionLoaded()) {
loadPermissionInfo();
}
return super.getPermission();
}
@Override
public String getOwner() {
if (!isPermissionLoaded()) {
loadPermissionInfo();
}
return super.getOwner();
}
@Override
public String getGroup() {
if (!isPermissionLoaded()) {
loadPermissionInfo();
}
return super.getGroup();
}
/**
* Load file permission information (UNIX symbol rwxrwxrwx, sticky bit info).
*
* To improve peformance, give priority to native stat() call. First try get
* permission information by using native JNI call then fall back to use non
* native (ProcessBuilder) call in case native lib is not loaded or native
* call is not successful
*/
private synchronized void loadPermissionInfo() {
if (!isPermissionLoaded() && NativeIO.isAvailable()) {
try {
loadPermissionInfoByNativeIO();
} catch (IOException ex) {
LOG.debug("Native call failed", ex);
}
}
if (!isPermissionLoaded()) {
loadPermissionInfoByNonNativeIO();
}
}
/// loads permissions, owner, and group from `ls -ld`
@VisibleForTesting
void loadPermissionInfoByNonNativeIO() {
IOException e = null;
try {
String output = FileUtil.execCommand(new File(getPath().toUri()),
Shell.getGetPermissionCommand());
StringTokenizer t =
new StringTokenizer(output, Shell.TOKEN_SEPARATOR_REGEX);
//expected format
//-rw------- 1 username groupname ...
String permission = t.nextToken();
if (permission.length() > FsPermission.MAX_PERMISSION_LENGTH) {
//files with ACLs might have a '+'
permission = permission.substring(0,
FsPermission.MAX_PERMISSION_LENGTH);
}
setPermission(FsPermission.valueOf(permission));
t.nextToken();
String owner = t.nextToken();
String group = t.nextToken();
// If on windows domain, token format is DOMAIN\\user and we want to
// extract only the user name
// same as to the group name
if (Shell.WINDOWS) {
owner = removeDomain(owner);
group = removeDomain(group);
}
setOwner(owner);
setGroup(group);
} catch (Shell.ExitCodeException ioe) {
if (ioe.getExitCode() != 1) {
e = ioe;
} else {
setPermission(null);
setOwner(null);
setGroup(null);
}
} catch (IOException ioe) {
e = ioe;
} finally {
if (e != null) {
throw new RuntimeException("Error while running command to get " +
"file permissions : " +
StringUtils.stringifyException(e));
}
}
}
// In Windows, domain name is added.
// For example, given machine name (domain name) dname, user name i, then
// the result for user is dname\\i and for group is dname\\None. So we need
// remove domain name as follows:
// DOMAIN\\user => user, DOMAIN\\group => group
private String removeDomain(String str) {
int index = str.indexOf("\\");
if (index != -1) {
str = str.substring(index + 1);
}
return str;
}
// loads permissions, owner, and group from `ls -ld`
// but use JNI to more efficiently get file mode (permission, owner, group)
// by calling file stat() in *nix or some similar calls in Windows
@VisibleForTesting
void loadPermissionInfoByNativeIO() throws IOException {
Path path = getPath();
String pathName = path.toUri().getPath();
// remove leading slash for Windows path
if (Shell.WINDOWS && pathName.startsWith("/")) {
pathName = pathName.substring(1);
}
try {
NativeIO.POSIX.Stat stat = NativeIO.POSIX.getStat(pathName);
String owner = stat.getOwner();
String group = stat.getGroup();
int mode = stat.getMode();
setOwner(owner);
setGroup(group);
setPermission(new FsPermission(mode));
} catch (IOException e) {
setOwner(null);
setGroup(null);
setPermission(null);
throw e;
}
}
@Override
public void write(DataOutput out) throws IOException {
if (!isPermissionLoaded()) {
loadPermissionInfo();
}
super.write(out);
}
}
/**
* Use the command chown to set owner.
*/
@Override
public void setOwner(Path p, String username, String groupname)
throws IOException {
FileUtil.setOwner(pathToFile(p), username, groupname);
}
/**
* Use the command chmod to set permission.
*/
@Override
public void setPermission(Path p, FsPermission permission)
throws IOException {
if (NativeIO.isAvailable()) {
NativeIO.POSIX.chmod(pathToFile(p).getCanonicalPath(),
permission.toShort());
} else {
String perm = String.format("%04o", permission.toShort());
Shell.execCommand(Shell.getSetPermissionCommand(perm, false,
FileUtil.makeShellPath(pathToFile(p), true)));
}
}
/**
* Sets the {@link Path}'s last modified time and last access time to
* the given valid times.
*
* @param mtime the modification time to set (only if no less than zero).
* @param atime the access time to set (only if no less than zero).
* @throws IOException if setting the times fails.
*/
@Override
public void setTimes(Path p, long mtime, long atime) throws IOException {
try {
BasicFileAttributeView view = Files.getFileAttributeView(
pathToFile(p).toPath(), BasicFileAttributeView.class);
FileTime fmtime = (mtime >= 0) ? FileTime.fromMillis(mtime) : null;
FileTime fatime = (atime >= 0) ? FileTime.fromMillis(atime) : null;
view.setTimes(fmtime, fatime, null);
} catch (NoSuchFileException e) {
throw new FileNotFoundException("File " + p + " does not exist");
}
}
/**
* Hook to implement support for {@link PathHandle} operations.
* @param stat Referent in the target FileSystem
* @param opts Constraints that determine the validity of the
* {@link PathHandle} reference.
*/
protected PathHandle createPathHandle(FileStatus stat,
Options.HandleOpt... opts) {
if (stat.isDirectory() || stat.isSymlink()) {
throw new IllegalArgumentException("PathHandle only available for files");
}
String authority = stat.getPath().toUri().getAuthority();
if (authority != null && !authority.equals("file://")) {
throw new IllegalArgumentException("Wrong FileSystem: " + stat.getPath());
}
Options.HandleOpt.Data data =
Options.HandleOpt.getOpt(Options.HandleOpt.Data.class, opts)
.orElse(Options.HandleOpt.changed(false));
Options.HandleOpt.Location loc =
Options.HandleOpt.getOpt(Options.HandleOpt.Location.class, opts)
.orElse(Options.HandleOpt.moved(false));
if (loc.allowChange()) {
throw new UnsupportedOperationException("Tracking file movement in " +
"basic FileSystem is not supported");
}
final Path p = stat.getPath();
final Optional mtime = !data.allowChange()
? Optional.of(stat.getModificationTime())
: Optional.empty();
return new LocalFileSystemPathHandle(p.toString(), mtime);
}
@Override
public boolean supportsSymlinks() {
return true;
}
@SuppressWarnings("deprecation")
@Override
public void createSymlink(Path target, Path link, boolean createParent)
throws IOException {
if (!FileSystem.areSymlinksEnabled()) {
throw new UnsupportedOperationException("Symlinks not supported");
}
final String targetScheme = target.toUri().getScheme();
if (targetScheme != null && !"file".equals(targetScheme)) {
throw new IOException("Unable to create symlink to non-local file "+
"system: "+target.toString());
}
if (createParent) {
mkdirs(link.getParent());
}
// NB: Use createSymbolicLink in java.nio.file.Path once available
int result = FileUtil.symLink(target.toString(),
makeAbsolute(link).toString());
if (result != 0) {
throw new IOException("Error " + result + " creating symlink " +
link + " to " + target);
}
}
/**
* Return a FileStatus representing the given path. If the path refers
* to a symlink return a FileStatus representing the link rather than
* the object the link refers to.
*/
@Override
public FileStatus getFileLinkStatus(final Path f) throws IOException {
FileStatus fi = getFileLinkStatusInternal(f, false);
// getFileLinkStatus is supposed to return a symlink with a
// qualified path
if (fi.isSymlink()) {
Path targetQual = FSLinkResolver.qualifySymlinkTarget(this.getUri(),
fi.getPath(), fi.getSymlink());
fi.setSymlink(targetQual);
}
return fi;
}
/**
* Public {@link FileStatus} methods delegate to this function, which in turn
* either call the new {@link Stat} based implementation or the deprecated
* methods based on platform support.
*
* @param f Path to stat
* @param dereference whether to dereference the final path component if a
* symlink
* @return FileStatus of f
* @throws IOException
*/
private FileStatus getFileLinkStatusInternal(final Path f,
boolean dereference) throws IOException {
if (!useDeprecatedFileStatus) {
return getNativeFileLinkStatus(f, dereference);
} else if (dereference) {
return deprecatedGetFileStatus(f);
} else {
return deprecatedGetFileLinkStatusInternal(f);
}
}
/**
* Deprecated. Remains for legacy support. Should be removed when {@link Stat}
* gains support for Windows and other operating systems.
*/
@Deprecated
private FileStatus deprecatedGetFileLinkStatusInternal(final Path f)
throws IOException {
String target = FileUtil.readLink(new File(f.toString()));
try {
FileStatus fs = getFileStatus(f);
// If f refers to a regular file or directory
if (target.isEmpty()) {
return fs;
}
// Otherwise f refers to a symlink
return new FileStatus(fs.getLen(),
false,
fs.getReplication(),
fs.getBlockSize(),
fs.getModificationTime(),
fs.getAccessTime(),
fs.getPermission(),
fs.getOwner(),
fs.getGroup(),
new Path(target),
f);
} catch (FileNotFoundException e) {
/* The exists method in the File class returns false for dangling
* links so we can get a FileNotFoundException for links that exist.
* It's also possible that we raced with a delete of the link. Use
* the readBasicFileAttributes method in java.nio.file.attributes
* when available.
*/
if (!target.isEmpty()) {
return new FileStatus(0, false, 0, 0, 0, 0, FsPermission.getDefault(),
"", "", new Path(target), f);
}
// f refers to a file or directory that does not exist
throw e;
}
}
/**
* Calls out to platform's native stat(1) implementation to get file metadata
* (permissions, user, group, atime, mtime, etc). This works around the lack
* of lstat(2) in Java 6.
*
* Currently, the {@link Stat} class used to do this only supports Linux
* and FreeBSD, so the old {@link #deprecatedGetFileLinkStatusInternal(Path)}
* implementation (deprecated) remains further OS support is added.
*
* @param f File to stat
* @param dereference whether to dereference symlinks
* @return FileStatus of f
* @throws IOException
*/
private FileStatus getNativeFileLinkStatus(final Path f,
boolean dereference) throws IOException {
checkPath(f);
Stat stat = new Stat(f, getDefaultBlockSize(f), dereference, this);
FileStatus status = stat.getFileStatus();
return status;
}
@Override
public Path getLinkTarget(Path f) throws IOException {
FileStatus fi = getFileLinkStatusInternal(f, false);
// return an unqualified symlink target
return fi.getSymlink();
}
}