001/*
002 * CDDL HEADER START
003 *
004 * The contents of this file are subject to the terms of the
005 * Common Development and Distribution License, Version 1.0 only
006 * (the "License").  You may not use this file except in compliance
007 * with the License.
008 *
009 * You can obtain a copy of the license at legal-notices/CDDLv1_0.txt
010 * or http://forgerock.org/license/CDDLv1.0.html.
011 * See the License for the specific language governing permissions
012 * and limitations under the License.
013 *
014 * When distributing Covered Code, include this CDDL HEADER in each
015 * file and include the License file at legal-notices/CDDLv1_0.txt.
016 * If applicable, add the following below this CDDL HEADER, with the
017 * fields enclosed by brackets "[]" replaced with your own identifying
018 * information:
019 *      Portions Copyright [yyyy] [name of copyright owner]
020 *
021 * CDDL HEADER END
022 *
023 *
024 *      Copyright 2006-2010 Sun Microsystems, Inc.
025 *      Portions Copyright 2014-2015 ForgeRock AS
026 */
027package org.opends.server.backends.pluggable;
028
029import org.forgerock.opendj.ldap.ByteSequence;
030import org.forgerock.opendj.ldap.ByteString;
031import org.forgerock.opendj.ldap.ByteStringBuilder;
032import org.opends.server.types.DN;
033
034/**
035 * Handles the disk representation of LDAP data.
036 */
037public class DnKeyFormat
038{
039
040  /** The format version used by this class to encode and decode a ByteString. */
041  static final byte FORMAT_VERSION = 0x01;
042
043  /**
044   * Find the length of bytes that represents the superior DN of the given DN
045   * key. The superior DN is represented by the initial bytes of the DN key.
046   *
047   * @param dnKey
048   *          The key value of the DN.
049   * @return The length of the superior DN or -1 if the given dn is the root DN
050   *         or 0 if the superior DN is removed.
051   */
052  static int findDNKeyParent(ByteSequence dnKey)
053  {
054    if (dnKey.length() == 0)
055    {
056      // This is the root or base DN
057      return -1;
058    }
059
060    // We will walk backwards through the buffer
061    // and find the first unescaped NORMALIZED_RDN_SEPARATOR
062    for (int i = dnKey.length() - 1; i >= 0; i--)
063    {
064      if (dnKey.byteAt(i) == DN.NORMALIZED_RDN_SEPARATOR && i - 1 >= 0 && dnKey.byteAt(i - 1) != DN.NORMALIZED_ESC_BYTE)
065      {
066        return i;
067      }
068    }
069    return 0;
070  }
071
072  /**
073   * Create a DN key from an entry DN.
074   *
075   * @param dn The entry DN.
076   * @param prefixRDNs The number of prefix RDNs to remove from the encoded
077   *                   representation.
078   * @return A ByteString containing the key.
079   */
080  static ByteString dnToDNKey(DN dn, int prefixRDNs)
081  {
082    final ByteStringBuilder builder = new ByteStringBuilder(128);
083    final int startSize = dn.size() - prefixRDNs - 1;
084    for (int i = startSize; i >= 0; i--)
085    {
086        builder.append(DN.NORMALIZED_RDN_SEPARATOR);
087        dn.getRDN(i).toNormalizedByteString(builder);
088    }
089    return builder.toByteString();
090  }
091
092  static ByteStringBuilder beforeKey(final ByteSequence key)
093  {
094    final ByteStringBuilder beforeKey = new ByteStringBuilder(key.length() + 1);
095    beforeKey.append(key);
096    beforeKey.append((byte) 0x00);
097    return beforeKey;
098  }
099
100  static ByteStringBuilder afterKey(final ByteSequence key)
101  {
102    final ByteStringBuilder afterKey = new ByteStringBuilder(key.length() + 1);
103    afterKey.append(key);
104    afterKey.append((byte) 0x01);
105    return afterKey;
106  }
107}