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Diffstat (limited to 'src/VBox/Runtime/common/table/avl_Destroy.cpp.h')
| -rw-r--r-- | src/VBox/Runtime/common/table/avl_Destroy.cpp.h | 120 |
1 files changed, 120 insertions, 0 deletions
diff --git a/src/VBox/Runtime/common/table/avl_Destroy.cpp.h b/src/VBox/Runtime/common/table/avl_Destroy.cpp.h new file mode 100644 index 00000000..3b12041d --- /dev/null +++ b/src/VBox/Runtime/common/table/avl_Destroy.cpp.h @@ -0,0 +1,120 @@ +/* $Id: avl_Destroy.cpp.h $ */ +/** @file + * kAVLDestroy - Walk the tree calling a callback to destroy all the nodes. + */ + +/* + * Copyright (C) 2006-2022 Oracle and/or its affiliates. + * + * This file is part of VirtualBox base platform packages, as + * available from https://www.virtualbox.org. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, in version 3 of the + * License. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <https://www.gnu.org/licenses>. + * + * The contents of this file may alternatively be used under the terms + * of the Common Development and Distribution License Version 1.0 + * (CDDL), a copy of it is provided in the "COPYING.CDDL" file included + * in the VirtualBox distribution, in which case the provisions of the + * CDDL are applicable instead of those of the GPL. + * + * You may elect to license modified versions of this file under the + * terms and conditions of either the GPL or the CDDL or both. + * + * SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0 + */ + +#ifndef _kAVLDestroy_h_ +#define _kAVLDestroy_h_ + + +/** + * Destroys the specified tree, starting with the root node and working our way down. + * + * @returns 0 on success. + * @returns Return value from callback on failure. On failure, the tree will be in + * an unbalanced condition and only further calls to the Destroy should be + * made on it. Note that the node we fail on will be considered dead and + * no action is taken to link it back into the tree. + * @param ppTree Pointer to the AVL-tree root node pointer. + * @param pfnCallBack Pointer to callback function. + * @param pvUser User parameter passed on to the callback function. + */ +KAVL_DECL(int) KAVL_FN(Destroy)(PPKAVLNODECORE ppTree, PKAVLCALLBACK pfnCallBack, void *pvUser) +{ + unsigned cEntries; + PKAVLNODECORE apEntries[KAVL_MAX_STACK]; + int rc; + + if (*ppTree == KAVL_NULL) + return VINF_SUCCESS; + + cEntries = 1; + apEntries[0] = KAVL_GET_POINTER(ppTree); + while (cEntries > 0) + { + /* + * Process the subtrees first. + */ + PKAVLNODECORE pNode = apEntries[cEntries - 1]; + if (pNode->pLeft != KAVL_NULL) + apEntries[cEntries++] = KAVL_GET_POINTER(&pNode->pLeft); + else if (pNode->pRight != KAVL_NULL) + apEntries[cEntries++] = KAVL_GET_POINTER(&pNode->pRight); + else + { +#ifdef KAVL_EQUAL_ALLOWED + /* + * Process nodes with the same key. + */ + while (pNode->pList != KAVL_NULL) + { + PKAVLNODECORE pEqual = KAVL_GET_POINTER(&pNode->pList); + KAVL_SET_POINTER(&pNode->pList, KAVL_GET_POINTER_NULL(&pEqual->pList)); + pEqual->pList = KAVL_NULL; + + rc = pfnCallBack(pEqual, pvUser); + if (rc != VINF_SUCCESS) + return rc; + } +#endif + + /* + * Unlink the node. + */ + if (--cEntries > 0) + { + PKAVLNODECORE pParent = apEntries[cEntries - 1]; + if (KAVL_GET_POINTER(&pParent->pLeft) == pNode) + pParent->pLeft = KAVL_NULL; + else + pParent->pRight = KAVL_NULL; + } + else + *ppTree = KAVL_NULL; + + kASSERT(pNode->pLeft == KAVL_NULL); + kASSERT(pNode->pRight == KAVL_NULL); + rc = pfnCallBack(pNode, pvUser); + if (rc != VINF_SUCCESS) + return rc; + } + } /* while */ + + kASSERT(*ppTree == KAVL_NULL); + + return VINF_SUCCESS; +} + +#endif + |