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108 lines
3.5 KiB
C++
108 lines
3.5 KiB
C++
/*
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* PROGRAM: JRD Access Method
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* MODULE: btn.h
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* DESCRIPTION: B-tree management code
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*
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* The contents of this file are subject to the Initial
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* Developer's Public License Version 1.0 (the "License");
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* you may not use this file except in compliance with the
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* License. You may obtain a copy of the License at
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* http://www.ibphoenix.com/main.nfs?a=ibphoenix&page=ibp_idpl.
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*
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* Software distributed under the License is distributed AS IS,
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* WITHOUT WARRANTY OF ANY KIND, either express or implied.
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* See the License for the specific language governing rights
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* and limitations under the License.
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*
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* The Original Code was created by Arno Brinkman
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* for the Firebird Open Source RDBMS project.
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*
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* Copyright (c) 2003 Arno Brinkman and all contributors
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* signed below.
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*
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* All Rights Reserved.
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* Contributor(s): ______________________________________.
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*/
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#ifndef JRD_BTN_H_
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#define JRD_BTN_H_
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#include "firebird.h" // needed for get_long
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#include "memory_routines.h" // needed for get_long
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#include "../jrd/common.h"
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#include "../jrd/ods.h"
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#include "../include/fb_vector.h"
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#include "../common/classes/array.h"
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// format of expanded index node, used for backwards navigation
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typedef struct btx {
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UCHAR btx_previous_length; // AB: total size for previous node --length of data for previous node
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UCHAR btx_btr_previous_length; // length of data for previous node on btree page
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UCHAR btx_data[1]; // expanded data element
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} *BTX;
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#define BTX_SIZE 2
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// format of expanded index buffer
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struct jrd_exp {
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USHORT exp_length;
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ULONG exp_incarnation;
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btx exp_nodes[1];
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};
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#define EXP_SIZE OFFSETA (jrd_exp*, exp_nodes)
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struct dynKey {
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USHORT keyLength;
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UCHAR* keyData;
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};
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typedef Firebird::vector<dynKey*> keyList;
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typedef Firebird::HalfStaticArray<IndexJumpNode, 32> jumpNodeList;
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namespace BTreeNode {
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USHORT computePrefix(const UCHAR* prevString, USHORT prevLength,
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const UCHAR* string, USHORT length);
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SLONG findPageInDuplicates(const btree_page* page, UCHAR* pointer,
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SLONG previousNumber, SLONG findRecordNumber);
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USHORT getJumpNodeSize(const IndexJumpNode* jumpNode, SCHAR flags);
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USHORT getNodeSize(const IndexNode* indexNode, SCHAR flags, bool leafNode = true);
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UCHAR* getPointerFirstNode(btree_page* page, IndexJumpInfo* jumpInfo = NULL);
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bool isEndBucket(const IndexNode* indexNode, bool leafNode = true);
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bool isEndLevel(const IndexNode* indexNode, bool leafNode = true);
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bool keyEquality(USHORT length, const UCHAR* data, const IndexNode* indexNode);
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#ifdef SCROLLABLE_CURSORS
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UCHAR* lastNode(btree_page* page, jrd_exp* expanded_page, BTX* expanded_node);
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#endif
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UCHAR* nextNode(IndexNode* node, UCHAR* pointer,
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SCHAR flags, BTX* expanded_node);
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UCHAR* previousNode(IndexNode* node, UCHAR* pointer,
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SCHAR flags, BTX* expanded_node);
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void quad_put(SLONG value, UCHAR *data);
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UCHAR* readJumpInfo(IndexJumpInfo* jumpInfo, UCHAR* pagePointer);
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UCHAR* readJumpNode(IndexJumpNode* jumpNode, UCHAR* pagePointer, SCHAR flags);
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UCHAR* readNode(IndexNode* indexNode, UCHAR* pagePointer, SCHAR flags,
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bool leafNode);
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UCHAR* writeJumpInfo(btree_page* page, const IndexJumpInfo* jumpInfo);
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UCHAR* writeJumpNode(IndexJumpNode* jumpNode, UCHAR* pagePointer, SCHAR flags);
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UCHAR* writeNode(IndexNode* indexNode, UCHAR* pagePointer, SCHAR flags,
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bool leafNode, bool withData = true);
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void setEndBucket(IndexNode* indexNode, bool leafNode = true);
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void setEndLevel(IndexNode* indexNode, bool leafNode = true);
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} // namespace BTreeNode
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#endif // JRD_BTN_H_
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