ubuntu/vbox/vboxguest/common/table/avl_RemoveBestFit.cpp.h

   1 /* $Id: avl_RemoveBestFit.cpp.h $ */
   2 /** @file
   3  * kAVLRemoveBestFit - Remove Best Fit routine for AVL trees.
   4  *                     Intended specially on heaps. The tree should allow duplicate keys.
   5  *
   6  */
   7
   8 /*
   9  * Copyright (C) 2006-2017 Oracle Corporation
  10  *
  11  * This file is part of VirtualBox Open Source Edition (OSE), as
  12  * available from http://www.virtualbox.org. This file is free software;
  13  * you can redistribute it and/or modify it under the terms of the GNU
  14  * General Public License (GPL) as published by the Free Software
  15  * Foundation, in version 2 as it comes in the "COPYING" file of the
  16  * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
  17  * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
  18  *
  19  * The contents of this file may alternatively be used under the terms
  20  * of the Common Development and Distribution License Version 1.0
  21  * (CDDL) only, as it comes in the "COPYING.CDDL" file of the
  22  * VirtualBox OSE distribution, in which case the provisions of the
  23  * CDDL are applicable instead of those of the GPL.
  24  *
  25  * You may elect to license modified versions of this file under the
  26  * terms and conditions of either the GPL or the CDDL or both.
  27  */
  28
  29 #ifndef _kAVLRemoveBestFit_h_
  30 #define _kAVLRemoveBestFit_h_
  31
  32
  33 /**
  34  * Finds the best fitting node in the tree for the given Key value.
  35  * And removes it.
  36  * @returns   Pointer to the best fitting node found.
  37  * @param     ppTree  Pointer to Pointer to the tree root node.
  38  * @param     Key     The Key of which is to be found a best fitting match for..
  39  * @param     fAbove  TRUE:  Returned node is have the closest key to Key from above.
  40  *                    FALSE: Returned node is have the closest key to Key from below.
  41  * @sketch    The best fitting node is always located in the searchpath above you.
  42  *            >= (above): The node where you last turned left.
  43  *            <= (below): the node where you last turned right.
  44  * @remark    This implementation should be speeded up slightly!
  45  */
  46 KAVL_DECL(PKAVLNODECORE) KAVL_FN(RemoveBestFit)(PPKAVLNODECORE ppTree, KAVLKEY Key, bool fAbove)
  47 {
  48     /*
  49      * If we find anything we'll have to remove the node and return it.
  50      * But, if duplicate keys are allowed we'll have to check for multiple
  51      * nodes first and return one of them before doing an expensive remove+insert.
  52      */
  53     PKAVLNODECORE   pNode = KAVL_FN(GetBestFit)(ppTree, Key, fAbove);
  54     if (pNode != NULL)
  55     {
  56 #ifdef KAVL_EQUAL_ALLOWED
  57         if (pNode->pList != KAVL_NULL)
  58         {
  59             PKAVLNODECORE pRet = KAVL_GET_POINTER(&pNode->pList);
  60             KAVL_SET_POINTER_NULL(&pNode->pList, &pRet->pList);
  61             return pRet;
  62         }
  63 #endif
  64         pNode = KAVL_FN(Remove)(ppTree, pNode->Key);
  65     }
  66     return pNode;
  67 }
  68
  69
  70 #endif