/**
* 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.hdfs.server.namenode;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.fs.permission.FsPermission;
import org.apache.hadoop.fs.permission.PermissionStatus;
import org.apache.hadoop.hdfs.protocol.QuotaExceededException;
import org.apache.hadoop.hdfs.server.namenode.snapshot.Snapshot;
import org.apache.hadoop.util.LightWeightGSet.LinkedElement;
import com.google.common.base.Preconditions;
/**
* {@link INode} with additional fields including id, name, permission,
* access time and modification time.
*/
@InterfaceAudience.Private
public abstract class INodeWithAdditionalFields extends INode
implements LinkedElement {
static enum PermissionStatusFormat {
MODE(0, 16),
GROUP(MODE.OFFSET + MODE.LENGTH, 25),
USER(GROUP.OFFSET + GROUP.LENGTH, 23);
final int OFFSET;
final int LENGTH; //bit length
final long MASK;
PermissionStatusFormat(int offset, int length) {
OFFSET = offset;
LENGTH = length;
MASK = ((-1L) >>> (64 - LENGTH)) << OFFSET;
}
long retrieve(long record) {
return (record & MASK) >>> OFFSET;
}
long combine(long bits, long record) {
return (record & ~MASK) | (bits << OFFSET);
}
/** Encode the {@link PermissionStatus} to a long. */
static long toLong(PermissionStatus ps) {
long permission = 0L;
final int user = SerialNumberManager.INSTANCE.getUserSerialNumber(
ps.getUserName());
permission = USER.combine(user, permission);
final int group = SerialNumberManager.INSTANCE.getGroupSerialNumber(
ps.getGroupName());
permission = GROUP.combine(group, permission);
final int mode = ps.getPermission().toShort();
permission = MODE.combine(mode, permission);
return permission;
}
}
/** The inode id. */
final private long id;
/**
* The inode name is in java UTF8 encoding;
* The name in HdfsFileStatus should keep the same encoding as this.
* if this encoding is changed, implicitly getFileInfo and listStatus in
* clientProtocol are changed; The decoding at the client
* side should change accordingly.
*/
private byte[] name = null;
/**
* Permission encoded using {@link PermissionStatusFormat}.
* Codes other than {@link #clonePermissionStatus(INodeWithAdditionalFields)}
* and {@link #updatePermissionStatus(PermissionStatusFormat, long)}
* should not modify it.
*/
private long permission = 0L;
/** The last modification time*/
private long modificationTime = 0L;
/** The last access time*/
private long accessTime = 0L;
/** For implementing {@link LinkedElement}. */
private LinkedElement next = null;
private INodeWithAdditionalFields(INode parent, long id, byte[] name,
long permission, long modificationTime, long accessTime) {
super(parent);
this.id = id;
this.name = name;
this.permission = permission;
this.modificationTime = modificationTime;
this.accessTime = accessTime;
}
INodeWithAdditionalFields(long id, byte[] name, PermissionStatus permissions,
long modificationTime, long accessTime) {
this(null, id, name, PermissionStatusFormat.toLong(permissions),
modificationTime, accessTime);
}
/** @param other Other node to be copied */
INodeWithAdditionalFields(INodeWithAdditionalFields other) {
this(other.getParentReference() != null ? other.getParentReference()
: other.getParent(), other.getId(), other.getLocalNameBytes(),
other.permission, other.modificationTime, other.accessTime);
}
@Override
public void setNext(LinkedElement next) {
this.next = next;
}
@Override
public LinkedElement getNext() {
return next;
}
/** Get inode id */
@Override
public final long getId() {
return this.id;
}
@Override
public final byte[] getLocalNameBytes() {
return name;
}
@Override
public final void setLocalName(byte[] name) {
this.name = name;
}
/** Clone the {@link PermissionStatus}. */
final void clonePermissionStatus(INodeWithAdditionalFields that) {
this.permission = that.permission;
}
@Override
final PermissionStatus getPermissionStatus(Snapshot snapshot) {
return new PermissionStatus(getUserName(snapshot), getGroupName(snapshot),
getFsPermission(snapshot));
}
private final void updatePermissionStatus(PermissionStatusFormat f, long n) {
this.permission = f.combine(n, permission);
}
@Override
final String getUserName(Snapshot snapshot) {
if (snapshot != null) {
return getSnapshotINode(snapshot).getUserName();
}
int n = (int)PermissionStatusFormat.USER.retrieve(permission);
return SerialNumberManager.INSTANCE.getUser(n);
}
@Override
final void setUser(String user) {
int n = SerialNumberManager.INSTANCE.getUserSerialNumber(user);
updatePermissionStatus(PermissionStatusFormat.USER, n);
}
@Override
final String getGroupName(Snapshot snapshot) {
if (snapshot != null) {
return getSnapshotINode(snapshot).getGroupName();
}
int n = (int)PermissionStatusFormat.GROUP.retrieve(permission);
return SerialNumberManager.INSTANCE.getGroup(n);
}
@Override
final void setGroup(String group) {
int n = SerialNumberManager.INSTANCE.getGroupSerialNumber(group);
updatePermissionStatus(PermissionStatusFormat.GROUP, n);
}
@Override
final FsPermission getFsPermission(Snapshot snapshot) {
if (snapshot != null) {
return getSnapshotINode(snapshot).getFsPermission();
}
return new FsPermission(getFsPermissionShort());
}
@Override
public final short getFsPermissionShort() {
return (short)PermissionStatusFormat.MODE.retrieve(permission);
}
@Override
void setPermission(FsPermission permission) {
final short mode = permission.toShort();
updatePermissionStatus(PermissionStatusFormat.MODE, mode);
}
@Override
public long getPermissionLong() {
return permission;
}
@Override
final long getModificationTime(Snapshot snapshot) {
if (snapshot != null) {
return getSnapshotINode(snapshot).getModificationTime();
}
return this.modificationTime;
}
/** Update modification time if it is larger than the current value. */
@Override
public final INode updateModificationTime(long mtime, Snapshot latest,
final INodeMap inodeMap) throws QuotaExceededException {
Preconditions.checkState(isDirectory());
if (mtime <= modificationTime) {
return this;
}
return setModificationTime(mtime, latest, inodeMap);
}
final void cloneModificationTime(INodeWithAdditionalFields that) {
this.modificationTime = that.modificationTime;
}
@Override
public final void setModificationTime(long modificationTime) {
this.modificationTime = modificationTime;
}
@Override
final long getAccessTime(Snapshot snapshot) {
if (snapshot != null) {
return getSnapshotINode(snapshot).getAccessTime();
}
return accessTime;
}
/**
* Set last access time of inode.
*/
@Override
public final void setAccessTime(long accessTime) {
this.accessTime = accessTime;
}
}