NfsReaddirplusResponse.java

/**
 * Copyright 2016-2018 Dell Inc. or its subsidiaries. All rights reserved.
 *
 * <p>Licensed under the Apache License, Version 2.0 (the "License"). You may not use this file
 * except in compliance with the License. A copy of the License is located at
 *
 * <p>http://www.apache.org/licenses/LICENSE-2.0.txt
 *
 * <p>or in the "license" file accompanying this file. This file 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 com.emc.ecs.nfsclient.nfs;

import com.emc.ecs.nfsclient.rpc.RpcException;
import com.emc.ecs.nfsclient.rpc.Xdr;
import java.util.ArrayList;
import java.util.List;

/**
 * The response, as specified by RFC 1813 (https://tools.ietf.org/html/rfc1813).
 *
 * <p>Procedure READDIRPLUS retrieves a variable number of entries from a file system directory and
 * returns complete information about each along with information to allow the client to request
 * additional directory entries in a subsequent READDIRPLUS. READDIRPLUS differs from READDIR only
 * in the amount of information returned for each entry. In READDIR, each entry returns the filename
 * and the fileid. In READDIRPLUS, each entry returns the name, the fileid, attributes (including
 * the fileid), and file handle.
 *
 * @author seibed
 */
public class NfsReaddirplusResponse extends NfsResponseBase {

  /** The last <code>cookie</code> from the server, for use in the next request */
  private long _cookie;

  /** The <code>cookieverf</code> from the server, for use in the next request */
  private long _cookieverf;

  /** The list of entries */
  List<NfsDirectoryPlusEntry> _entries;

  /**
   * <ul>
   *   <li><code>true</code> if the end of file is reached.
   *   <li><code>false</code> otherwise.
   * </ul>
   */
  private boolean _eof;

  /**
   * Creates the response, as specified by RFC 1813 (https://tools.ietf.org/html/rfc1813).
   *
   * <p>Procedure READDIRPLUS retrieves a variable number of entries from a file system directory
   * and returns complete information about each along with information to allow the client to
   * request additional directory entries in a subsequent READDIRPLUS. READDIRPLUS differs from
   * READDIR only in the amount of information returned for each entry. In READDIR, each entry
   * returns the filename and the fileid. In READDIRPLUS, each entry returns the name, the fileid,
   * attributes (including the fileid), and file handle.
   *
   * @param nfsVersion The NFS version number. This is ignored for now, as only NFSv3 is supported,
   *     but is included to allow future support for other versions.
   */
  public NfsReaddirplusResponse(int nfsVersion) {
    this(new ArrayList<NfsDirectoryPlusEntry>(), nfsVersion);
  }

  /**
   * Creates the response, as specified by RFC 1813 (https://tools.ietf.org/html/rfc1813).
   *
   * <p>Procedure READDIRPLUS retrieves a variable number of entries from a file system directory
   * and returns complete information about each along with information to allow the client to
   * request additional directory entries in a subsequent READDIRPLUS. READDIRPLUS differs from
   * READDIR only in the amount of information returned for each entry. In READDIR, each entry
   * returns the filename and the fileid. In READDIRPLUS, each entry returns the name, the fileid,
   * attributes (including the fileid), and file handle.
   *
   * @param entries A list in which to store the entries.
   * @param nfsVersion The NFS version number. This is ignored for now, as only NFSv3 is supported,
   *     but is included to allow future support for other versions.
   */
  public NfsReaddirplusResponse(List<NfsDirectoryPlusEntry> entries, int nfsVersion) {
    super();
    _entries = entries;
  }

  /** {@inheritDoc} */
  @Override
  public void unmarshalling(Xdr xdr) throws RpcException {
    super.unmarshalling(xdr);
    unmarshallingAttributes(xdr);
    if (stateIsOk()) {
      _cookieverf = xdr.getLong();

      // get directory entries
      while (xdr.getBoolean()) {
        NfsDirectoryPlusEntry entry = new NfsDirectoryPlusEntry(xdr);
        _entries.add(entry);
        _cookie = entry.getCookie();
      }

      // check whether it is the end of directory
      _eof = xdr.getBoolean();
    }
  }

  /** Returns the last <code>cookie</code> from the server, for use in the next request. */
  public long getCookie() {
    return _cookie;
  }

  /** Returns the <code>cookieverf</code> from the server, for use in the next request. */
  public long getCookieverf() {
    return _cookieverf;
  }

  /** Returns the list of entries. */
  public List<NfsDirectoryPlusEntry> getEntries() {
    return _entries;
  }

  /**
   * Returns
   *
   * <ul>
   *   <li><code>true</code> if the end of file is reached.
   *   <li><code>false</code> otherwise.
   * </ul>
   *
   * .
   */
  public boolean isEof() {
    return _eof;
  }
}