diff options
Diffstat (limited to 'source3')
| -rw-r--r-- | source3/ubiqx/ubi_AVLtree.c | 573 | ||||
| -rw-r--r-- | source3/ubiqx/ubi_AVLtree.h | 252 |
2 files changed, 0 insertions, 825 deletions
diff --git a/source3/ubiqx/ubi_AVLtree.c b/source3/ubiqx/ubi_AVLtree.c deleted file mode 100644 index f2ed7f2854..0000000000 --- a/source3/ubiqx/ubi_AVLtree.c +++ /dev/null @@ -1,573 +0,0 @@ -/* ========================================================================== ** - * ubi_AVLtree.c - * - * Copyright (C) 1991-1998 by Christopher R. Hertel - * - * Email: crh@ubiqx.mn.org - * -------------------------------------------------------------------------- ** - * - * This module provides an implementation of AVL height balanced binary - * trees. (Adelson-Velskii, Landis 1962) - * - * This file implements the core of the height-balanced (AVL) tree management - * routines. The header file, ubi_AVLtree.h, contains function prototypes - * for all "exported" functions. - * - * -------------------------------------------------------------------------- ** - * - * This library is free software; you can redistribute it and/or - * modify it under the terms of the GNU Library General Public - * License as published by the Free Software Foundation; either - * version 2 of the License, or (at your option) any later version. - * - * This library 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 - * Library General Public License for more details. - * - * You should have received a copy of the GNU Library General Public - * License along with this library; if not, write to the Free - * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - * - * -------------------------------------------------------------------------- ** - * - * Log: ubi_AVLtree.c,v - * Revision 4.1 1998/05/20 04:35:50 crh - * The C file now includes ubi_null.h. See ubi_null.h for more info. - * - * Revision 4.0 1998/03/10 03:37:09 crh - * Major changes. - * By adding the AVL balance field to the base ubi_btNode structure, I no - * longer need AVL-specific ReplaceNode(), SwapNodes(), and InitNode() - * functions. The Remove() function is also simplified. It's all much - * cleaner. - * This is rev. 4.0. The 3.x series was dropped. - * - * Revision 2.5 1997/12/23 04:00:42 crh - * In this version, all constants & macros defined in the header file have - * the ubi_tr prefix. Also cleaned up anything that gcc complained about - * when run with '-pedantic -fsyntax-only -Wall'. - * - * Revision 2.4 1997/07/26 04:36:20 crh - * Andrew Leppard, aka "Grazgur", discovered that I still had my brains tied - * on backwards with respect to node deletion. I did some more digging and - * discovered that I was not changing the balance values correctly in the - * single rotation functions. Double rotation was working correctly because - * the formula for changing the balance values is the same for insertion or - * deletion. Not so for single rotation. - * - * I have tested the fix by loading the tree with over 44 thousand names, - * deleting 2,629 of them (all those in which the second character is 'u') - * and then walking the tree recursively to verify that the balance factor of - * each node is correct. Passed. - * - * Thanks Andrew! - * - * Also: - * + Changed ubi_TRUE and ubi_FALSE to ubi_trTRUE and ubi_trFALSE. - * + Rewrote the ubi_tr<func> macros because they weren't doing what I'd - * hoped they would do (see the bottom of the header file). They work now. - * - * Revision 2.3 1997/06/03 04:41:35 crh - * Changed TRUE and FALSE to ubi_TRUE and ubi_FALSE to avoid causing - * problems. - * - * Revision 2.2 1995/10/03 22:16:01 CRH - * Ubisized! - * - * Revision 2.1 95/03/09 23:45:59 CRH - * Added the ModuleID static string and function. These modules are now - * self-identifying. - * - * Revision 2.0 95/03/05 14:10:51 CRH - * This revision of ubi_AVLtree coincides with revision 2.0 of ubi_BinTree, - * and so includes all of the changes to that module. In addition, a bug in - * the node deletion process has been fixed. - * - * After rewriting the Locate() function in ubi_BinTree, I decided that it was - * time to overhaul this module. In the process, I discovered a bug related - * to node deletion. To fix the bug, I wrote function Debalance(). A quick - * glance will show that it is very similar to the Rebalance() function. In - * previous versions of this module, I tried to include the functionality of - * Debalance() within Rebalance(), with poor results. - * - * Revision 1.0 93/10/15 22:58:56 CRH - * With this revision, I have added a set of #define's that provide a single, - * standard API to all existing tree modules. Until now, each of the three - * existing modules had a different function and typedef prefix, as follows: - * - * Module Prefix - * ubi_BinTree ubi_bt - * ubi_AVLtree ubi_avl - * ubi_SplayTree ubi_spt - * - * To further complicate matters, only those portions of the base module - * (ubi_BinTree) that were superceeded in the new module had the new names. - * For example, if you were using ubi_SplayTree, the locate function was - * called "ubi_sptLocate", but the next and previous functions remained - * "ubi_btNext" and "ubi_btPrev". - * - * This was not too terrible if you were familiar with the modules and knew - * exactly which tree model you wanted to use. If you wanted to be able to - * change modules (for speed comparisons, etc), things could get messy very - * quickly. - * - * So, I have added a set of defined names that get redefined in any of the - * descendant modules. To use this standardized interface in your code, - * simply replace all occurances of "ubi_bt", "ubi_avl", and "ubi_spt" with - * "ubi_tr". The "ubi_tr" names will resolve to the correct function or - * datatype names for the module that you are using. Just remember to - * include the header for that module in your program file. Because these - * names are handled by the preprocessor, there is no added run-time - * overhead. - * - * Note that the original names do still exist, and can be used if you wish - * to write code directly to a specific module. This should probably only be - * done if you are planning to implement a new descendant type, such as - * red/black trees. CRH - * - * V0.0 - May, 1990 - Written by Christopher R. Hertel (CRH). - * - * ========================================================================= ** - */ - -#include "ubi_null.h" /* ubiqx NULL source. */ -#include "ubi_AVLtree.h" /* Header for THIS module. */ - -/* ========================================================================== ** - * Static data. - */ - -static char ModuleID[] = "ubi_AVLtree\n\ -\tRevision: 4.1 \n\ -\tDate: 1998/05/20 04:35:50 \n\ -\tAuthor: crh \n"; - -/* ========================================================================== ** - * The next set of functions are the AVL balancing routines. There are left - * and right, single and double rotations. The rotation routines handle the - * rotations and reconnect all tree pointers that might get confused by the - * rotations. A pointer to the new subtree root node is returned. - * - * Note that L1 and R1 are identical, except that all the RIGHTs and LEFTs - * are reversed. The same is true for L2 and R2. I'm sure that there is - * a clever way to reduce the amount of code by combining these functions, - * but it might involve additional overhead, and it would probably be a pain - * to read, debug, etc. - * -------------------------------------------------------------------------- ** - */ - -static ubi_btNodePtr L1( ubi_btNodePtr p ) - /* ------------------------------------------------------------------------ ** - * Single rotate left. - * - * Input: p - Pointer to the root of a tree (possibly a subtree). - * Output: A pointer to the new root of the same subtree (now that node - * p has been moved). - * ------------------------------------------------------------------------ ** - */ - { - ubi_btNodePtr tmp; - - tmp = p->Link[ubi_trRIGHT]; - p->Link[ubi_trRIGHT] = tmp->Link[ubi_trLEFT]; - tmp->Link[ubi_trLEFT] = p; - - tmp->Link[ubi_trPARENT] = p->Link[ubi_trPARENT]; - tmp->gender = p->gender; - if(tmp->Link[ubi_trPARENT]) - (tmp->Link[ubi_trPARENT])->Link[(int)(tmp->gender)] = tmp; - p->Link[ubi_trPARENT] = tmp; - p->gender = ubi_trLEFT; - if( p->Link[ubi_trRIGHT] ) - { - p->Link[ubi_trRIGHT]->Link[ubi_trPARENT] = p; - (p->Link[ubi_trRIGHT])->gender = ubi_trRIGHT; - } - p->balance -= ubi_trNormalize( tmp->balance ); - (tmp->balance)--; - return( tmp ); - } /* L1 */ - -static ubi_btNodePtr R1( ubi_btNodePtr p ) - /* ------------------------------------------------------------------------ ** - * Single rotate right. - * - * Input: p - Pointer to the root of a tree (possibly a subtree). - * Output: A pointer to the new root of the same subtree (now that node - * p has been moved). - * ------------------------------------------------------------------------ ** - */ - { - ubi_btNodePtr tmp; - - tmp = p->Link[ubi_trLEFT]; - p->Link[ubi_trLEFT] = tmp->Link[ubi_trRIGHT]; - tmp->Link[ubi_trRIGHT] = p; - - tmp->Link[ubi_trPARENT] = p->Link[ubi_trPARENT]; - tmp->gender = p->gender; - if(tmp->Link[ubi_trPARENT]) - (tmp->Link[ubi_trPARENT])->Link[(int)(tmp->gender)] = tmp; - p->Link[ubi_trPARENT] = tmp; - p->gender = ubi_trRIGHT; - if(p->Link[ubi_trLEFT]) - { - p->Link[ubi_trLEFT]->Link[ubi_trPARENT] = p; - p->Link[ubi_trLEFT]->gender = ubi_trLEFT; - } - p->balance -= ubi_trNormalize( tmp->balance ); - (tmp->balance)++; - return( tmp ); - } /* R1 */ - -static ubi_btNodePtr L2( ubi_btNodePtr tree ) - /* ------------------------------------------------------------------------ ** - * Double rotate left. - * - * Input: p - Pointer to the root of a tree (possibly a subtree). - * Output: A pointer to the new root of the same subtree (now that node - * p has been moved). - * ------------------------------------------------------------------------ ** - */ - { - ubi_btNodePtr tmp, newroot; - - tmp = tree->Link[ubi_trRIGHT]; - newroot = tmp->Link[ubi_trLEFT]; - tmp->Link[ubi_trLEFT] = newroot->Link[ubi_trRIGHT]; - newroot->Link[ubi_trRIGHT] = tmp; - tree->Link[ubi_trRIGHT] = newroot->Link[ubi_trLEFT]; - newroot->Link[ubi_trLEFT] = tree; - - newroot->Link[ubi_trPARENT] = tree->Link[ubi_trPARENT]; - newroot->gender = tree->gender; - tree->Link[ubi_trPARENT] = newroot; - tree->gender = ubi_trLEFT; - tmp->Link[ubi_trPARENT] = newroot; - tmp->gender = ubi_trRIGHT; - - if( tree->Link[ubi_trRIGHT] ) - { - tree->Link[ubi_trRIGHT]->Link[ubi_trPARENT] = tree; - tree->Link[ubi_trRIGHT]->gender = ubi_trRIGHT; - } - if( tmp->Link[ubi_trLEFT] ) - { - tmp->Link[ubi_trLEFT]->Link[ubi_trPARENT] = tmp; - tmp->Link[ubi_trLEFT]->gender = ubi_trLEFT; - } - if(newroot->Link[ubi_trPARENT]) - newroot->Link[ubi_trPARENT]->Link[(int)(newroot->gender)] = newroot; - - switch( newroot->balance ) - { - case ubi_trLEFT : - tree->balance = ubi_trEQUAL; tmp->balance = ubi_trRIGHT; break; - case ubi_trEQUAL: - tree->balance = ubi_trEQUAL; tmp->balance = ubi_trEQUAL; break; - case ubi_trRIGHT: - tree->balance = ubi_trLEFT; tmp->balance = ubi_trEQUAL; break; - } - newroot->balance = ubi_trEQUAL; - return( newroot ); - } /* L2 */ - -static ubi_btNodePtr R2( ubi_btNodePtr tree ) - /* ------------------------------------------------------------------------ ** - * Double rotate right. - * - * Input: p - Pointer to the root of a tree (possibly a subtree). - * Output: A pointer to the new root of the same subtree (now that node - * p has been moved). - * ------------------------------------------------------------------------ ** - */ - { - ubi_btNodePtr tmp, newroot; - - tmp = tree->Link[ubi_trLEFT]; - newroot = tmp->Link[ubi_trRIGHT]; - tmp->Link[ubi_trRIGHT] = newroot->Link[ubi_trLEFT]; - newroot->Link[ubi_trLEFT] = tmp; - tree->Link[ubi_trLEFT] = newroot->Link[ubi_trRIGHT]; - newroot->Link[ubi_trRIGHT] = tree; - - newroot->Link[ubi_trPARENT] = tree->Link[ubi_trPARENT]; - newroot->gender = tree->gender; - tree->Link[ubi_trPARENT] = newroot; - tree->gender = ubi_trRIGHT; - tmp->Link[ubi_trPARENT] = newroot; - tmp->gender = ubi_trLEFT; - - if( tree->Link[ubi_trLEFT] ) - { - tree->Link[ubi_trLEFT]->Link[ubi_trPARENT] = tree; - tree->Link[ubi_trLEFT]->gender = ubi_trLEFT; - } - if( tmp->Link[ubi_trRIGHT] ) - { - tmp->Link[ubi_trRIGHT]->Link[ubi_trPARENT] = tmp; - tmp->Link[ubi_trRIGHT]->gender = ubi_trRIGHT; - } - if(newroot->Link[ubi_trPARENT]) - newroot->Link[ubi_trPARENT]->Link[(int)(newroot->gender)] = newroot; - - switch( newroot->balance ) - { - case ubi_trLEFT : - tree->balance = ubi_trRIGHT; tmp->balance = ubi_trEQUAL; break; - case ubi_trEQUAL : - tree->balance = ubi_trEQUAL; tmp->balance = ubi_trEQUAL; break; - case ubi_trRIGHT : - tree->balance = ubi_trEQUAL; tmp->balance = ubi_trLEFT; break; - } - newroot->balance = ubi_trEQUAL; - return( newroot ); - } /* R2 */ - - -static ubi_btNodePtr Adjust( ubi_btNodePtr p, char LorR ) - /* ------------------------------------------------------------------------ ** - * Adjust the balance value at node *p. If necessary, rotate the subtree - * rooted at p. - * - * Input: p - A pointer to the node to be adjusted. One of the - * subtrees of this node has changed height, so the - * balance value at this node must be adjusted, possibly - * by rotating the tree at this node. - * LorR - Indicates the TALLER subtree. - * - * Output: A pointer to the (possibly new) root node of the subtree. - * - * Notes: This function may be called after a node has been added *or* - * deleted, so LorR indicates the TALLER subtree. - * ------------------------------------------------------------------------ ** - */ - { - if( p->balance != LorR ) - p->balance += ubi_trNormalize(LorR); - else - { - char tallerbal; /* Balance value of the root of the taller subtree of p. */ - - tallerbal = p->Link[(int)LorR]->balance; - if( ( ubi_trEQUAL == tallerbal ) || ( p->balance == tallerbal ) ) - p = ( (ubi_trLEFT==LorR) ? R1(p) : L1(p) ); /* single rotation */ - else - p = ( (ubi_trLEFT==LorR) ? R2(p) : L2(p) ); /* double rotation */ - } - return( p ); - } /* Adjust */ - -static ubi_btNodePtr Rebalance( ubi_btNodePtr Root, - ubi_btNodePtr subtree, - char LorR ) - /* ------------------------------------------------------------------------ ** - * Rebalance the tree following an insertion. - * - * Input: Root - A pointer to the root node of the whole tree. - * subtree - A pointer to the node that has just gained a new - * child. - * LorR - Gender of the child that has just been gained. - * - * Output: A pointer to the (possibly new) root of the AVL tree. - * Rebalancing the tree moves nodes around a bit, so the node - * that *was* the root, may not be the root when we're finished. - * - * Notes: Rebalance() must walk up the tree from where we are (which is - * where the latest change occurred), rebalancing the subtrees - * along the way. The rebalancing operation can stop if the - * change at the current subtree root won't affect the rest of - * the tree. In the case of an addition, if a subtree root's - * balance becomes EQUAL, then we know that the height of that - * subtree has not changed, so we can exit. - * ------------------------------------------------------------------------ ** - */ - { - while( subtree ) - { - subtree = Adjust( subtree, LorR ); - if( ubi_trPARENT == subtree->gender ) - return( subtree ); - if( ubi_trEQUAL == subtree->balance ) - return( Root ); - LorR = subtree->gender; - subtree = subtree->Link[ubi_trPARENT]; - } - return( Root ); - } /* Rebalance */ - -static ubi_btNodePtr Debalance( ubi_btNodePtr Root, - ubi_btNodePtr subtree, - char LorR ) - /* ------------------------------------------------------------------------ ** - * Rebalance the tree following a deletion. - * - * Input: Root - A pointer to the root node of the whole tree. - * subtree - A pointer to the node who's child has just "left the - * nest". - * LorR - Gender of the child that left. - * - * Output: A pointer to the (possibly new) root of the AVL tree. - * Rebalancing the tree moves nodes around a bit, so the node - * that *was* the root, may not be the root when we're finished. - * - * Notes: Debalance() is subtly different from Rebalance() (above) in - * two respects. - * * When it calls Adjust(), it passes the *opposite* of LorR. - * This is because LorR, as passed into Debalance() indicates - * the shorter subtree. As we move up the tree, LorR is - * assigned the gender of the node that we are leaving (i.e., - * the subtree that we just rebalanced). - * * We know that a subtree has not changed height if the - * balance becomes LEFT or RIGHT. This is the *opposite* of - * what happens in Rebalance(). - * ------------------------------------------------------------------------ ** - */ - { - while( subtree ) - { - subtree = Adjust( subtree, ubi_trRevWay(LorR) ); - if( ubi_trPARENT == subtree->gender ) - return( subtree ); - if( ubi_trEQUAL != subtree->balance ) - return( Root ); - LorR = subtree->gender; - subtree = subtree->Link[ubi_trPARENT]; - } - return( Root ); - } /* Debalance */ - -/* ========================================================================== ** - * Public, exported (ie. not static-ly declared) functions... - * -------------------------------------------------------------------------- ** - */ - -ubi_trBool ubi_avlInsert( ubi_btRootPtr RootPtr, - ubi_btNodePtr NewNode, - ubi_btItemPtr ItemPtr, - ubi_btNodePtr *OldNode ) - /* ------------------------------------------------------------------------ ** - * This function uses a non-recursive algorithm to add a new element to - * the tree. - * - * Input: RootPtr - a pointer to the ubi_btRoot structure that indicates - * the root of the tree to which NewNode is to be added. - * NewNode - a pointer to an ubi_btNode structure that is NOT - * part of any tree. - * ItemPtr - A pointer to the sort key that is stored within - * *NewNode. ItemPtr MUST point to information stored - * in *NewNode or an EXACT DUPLICATE. The key data - * indicated by ItemPtr is used to place the new node - * into the tree. - * OldNode - a pointer to an ubi_btNodePtr. When searching - * the tree, a duplicate node may be found. If - * duplicates are allowed, then the new node will - * be simply placed into the tree. If duplicates - * are not allowed, however, then one of two things - * may happen. - * 1) if overwritting *is not* allowed, this - * function will return FALSE (indicating that - * the new node could not be inserted), and - * *OldNode will point to the duplicate that is - * still in the tree. - * 2) if overwritting *is* allowed, then this - * function will swap **OldNode for *NewNode. - * In this case, *OldNode will point to the node - * that was removed (thus allowing you to free - * the node). - * ** If you are using overwrite mode, ALWAYS ** - * ** check the return value of this parameter! ** - * Note: You may pass NULL in this parameter, the - * function knows how to cope. If you do this, - * however, there will be no way to return a - * pointer to an old (ie. replaced) node (which is - * a problem if you are using overwrite mode). - * - * Output: a boolean value indicating success or failure. The function - * will return FALSE if the node could not be added to the tree. - * Such failure will only occur if duplicates are not allowed, - * nodes cannot be overwritten, AND a duplicate key was found - * within the tree. - * ------------------------------------------------------------------------ ** - */ - { - ubi_btNodePtr OtherP; - - if( !(OldNode) ) - OldNode = &OtherP; - if( ubi_btInsert( RootPtr, - (ubi_btNodePtr)NewNode, - ItemPtr, - (ubi_btNodePtr *)OldNode ) ) - { - if( (*OldNode) ) - NewNode->balance = (*OldNode)->balance; - else - { - NewNode->balance = ubi_trEQUAL; - RootPtr->root = (ubi_btNodePtr)Rebalance( (ubi_btNodePtr)RootPtr->root, - NewNode->Link[ubi_trPARENT], - NewNode->gender ); - } - return( ubi_trTRUE ); - } - return( ubi_trFALSE ); /* Failure: could not replace an existing node. */ - } /* ubi_avlInsert */ - -ubi_btNodePtr ubi_avlRemove( ubi_btRootPtr RootPtr, - ubi_btNodePtr DeadNode ) - /* ------------------------------------------------------------------------ ** - * This function removes the indicated node from the tree, after which the - * tree is rebalanced. - * - * Input: RootPtr - A pointer to the header of the tree that contains - * the node to be removed. - * DeadNode - A pointer to the node that will be removed. - * - * Output: This function returns a pointer to the node that was removed - * from the tree (ie. the same as DeadNode). - * - * Note: The node MUST be in the tree indicated by RootPtr. If not, - * strange and evil things will happen to your trees. - * - * ------------------------------------------------------------------------ ** - */ - { - /* Let the base binary tree module do the removal, then rebalance. */ - if( ubi_btRemove( RootPtr, DeadNode ) ) - RootPtr->root = Debalance( RootPtr->root, - DeadNode->Link[ubi_trPARENT], - DeadNode->gender ); - return( DeadNode ); - } /* ubi_avlRemove */ - -int ubi_avlModuleID( int size, char *list[] ) - /* ------------------------------------------------------------------------ ** - * Returns a set of strings that identify the module. - * - * Input: size - The number of elements in the array <list>. - * list - An array of pointers of type (char *). This array - * should, initially, be empty. This function will fill - * in the array with pointers to strings. - * Output: The number of elements of <list> that were used. If this value - * is less than <size>, the values of the remaining elements are - * not guaranteed. - * - * Notes: Please keep in mind that the pointers returned indicate strings - * stored in static memory. Don't free() them, don't write over - * them, etc. Just read them. - * ------------------------------------------------------------------------ ** - */ - { - if( size > 0 ) - { - list[0] = ModuleID; - if( size > 1 ) - return( 1 + ubi_btModuleID( --size, &(list[1]) ) ); - return( 1 ); - } - return( 0 ); - } /* ubi_avlModuleID */ - -/* ============================== The End ============================== */ diff --git a/source3/ubiqx/ubi_AVLtree.h b/source3/ubiqx/ubi_AVLtree.h deleted file mode 100644 index c70190cb62..0000000000 --- a/source3/ubiqx/ubi_AVLtree.h +++ /dev/null @@ -1,252 +0,0 @@ -#ifndef ubi_AVLtree_H -#define ubi_AVLtree_H -/* ========================================================================== ** - * ubi_AVLtree.h - * - * Copyright (C) 1991-1998 by Christopher R. Hertel - * - * Email: crh@ubiqx.mn.org - * -------------------------------------------------------------------------- ** - * - * This module provides an implementation of AVL height balanced binary - * trees. (Adelson-Velskii, Landis 1962) - * - * This header file contains the basic AVL structure and pointer typedefs - * as well as the prototypes needed to access the functions in the AVL - * module ubi_AVLtree. The .c file implements the low-level height balancing - * routines that manage the AVL tree, plus all of the basic primops for - * adding, searching for, and deleting nodes. - * - * -------------------------------------------------------------------------- ** - * - * This library is free software; you can redistribute it and/or - * modify it under the terms of the GNU Library General Public - * License as published by the Free Software Foundation; either - * version 2 of the License, or (at your option) any later version. - * - * This library 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 - * Library General Public License for more details. - * - * You should have received a copy of the GNU Library General Public - * License along with this library; if not, write to the Free - * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - * - * -------------------------------------------------------------------------- ** - * Log: ubi_AVLtree.h,v - * Revision 4.1 1998/05/20 04:35:50 crh - * The C file now includes ubi_null.h. See ubi_null.h for more info. - * - * Revision 4.0 1998/03/10 03:34:45 crh - * Major changes. - * By adding the AVL balance field to the base ubi_btNode structure, I no - * longer need AVL-specific ReplaceNode(), SwapNodes(), and InitNode() - * functions. The Remove() function is also simplified. It's all much - * cleaner. - * This is rev. 4.0. The 3.x series was dropped. - * - * Revision 2.5 1997/12/23 04:00:15 crh - * In this version, all constants & macros defined in the header file have - * the ubi_tr prefix. Also cleaned up anything that gcc complained about - * when run with '-pedantic -fsyntax-only -Wall'. - * - * Revision 2.4 1997/07/26 04:36:23 crh - * Andrew Leppard, aka "Grazgur", discovered that I still had my brains tied - * on backwards with respect to node deletion. I did some more digging and - * discovered that I was not changing the balance values correctly in the - * single rotation functions. Double rotation was working correctly because - * the formula for changing the balance values is the same for insertion or - * deletion. Not so for single rotation. - * - * I have tested the fix by loading the tree with over 44 thousand names, - * deleting 2,629 of them (all those in which the second character is 'u') - * and then walking the tree recursively to verify that the balance factor of - * each node is correct. Passed. - * - * Thanks Andrew! - * - * Also: - * + Changed ubi_TRUE and ubi_FALSE to ubi_trTRUE and ubi_trFALSE. - * + Rewrote the ubi_tr<func> macros because they weren't doing what I'd - * hoped they would do (see the bottom of the header file). They work now. - * - * Revision 2.3 1997/06/03 05:22:07 crh - * Changed TRUE and FALSE to ubi_TRUE and ubi_FALSE to avoid causing - * problems. - * - * Revision 2.2 1995/10/03 22:15:47 CRH - * Ubisized! - * - * Revision 2.1 95/03/09 23:46:44 CRH - * Added the ModuleID static string and function. These modules are now - * self-identifying. - * - * Revision 2.0 95/03/05 14:11:22 CRH - * This revision of ubi_AVLtree coincides with revision 2.0 of ubi_BinTree, - * and so includes all of the changes to that module. In addition, a bug in - * the node deletion process has been fixed. - * - * After rewriting the Locate() function in ubi_BinTree, I decided that it was - * time to overhaul this module. In the process, I discovered a bug related - * to node deletion. To fix the bug, I wrote function Debalance(). A quick - * glance will show that it is very similar to the Rebalance() function. In - * previous versions of this module, I tried to include the functionality of - * Debalance() within Rebalance(), with poor results. - * - * Revision 1.0 93/10/15 22:58:48 CRH - * With this revision, I have added a set of #define's that provide a single, - * standard API to all existing tree modules. Until now, each of the three - * existing modules had a different function and typedef prefix, as follows: - * - * Module Prefix - * ubi_BinTree ubi_bt - * ubi_AVLtree ubi_avl - * ubi_SplayTree ubi_spt - * - * To further complicate matters, only those portions of the base module - * (ubi_BinTree) that were superceeded in the new module had the new names. - * For example, if you were using ubi_SplayTree, the locate function was - * called "ubi_sptLocate", but the next and previous functions remained - * "ubi_btNext" and "ubi_btPrev". - * - * This was not too terrible if you were familiar with the modules and knew - * exactly which tree model you wanted to use. If you wanted to be able to - * change modules (for speed comparisons, etc), things could get messy very - * quickly. - * - * So, I have added a set of defined names that get redefined in any of the - * descendant modules. To use this standardized interface in your code, - * simply replace all occurances of "ubi_bt", "ubi_avl", and "ubi_spt" with - * "ubi_tr". The "ubi_tr" names will resolve to the correct function or - * datatype names for the module that you are using. Just remember to - * include the header for that module in your program file. Because these - * names are handled by the preprocessor, there is no added run-time - * overhead. - * - * Note that the original names do still exist, and can be used if you wish - * to write code directly to a specific module. This should probably only be - * done if you are planning to implement a new descendant type, such as - * red/black trees. CRH - * - * V0.0 - May, 1990 - Written by Christopher R. Hertel (CRH). - * - * ========================================================================= ** - */ - -#include "ubi_BinTree.h" /* Base erg binary tree support. */ - -/* -------------------------------------------------------------------------- ** - * Function prototypes. - * -------------------------------------------------------------------------- ** - */ - -ubi_trBool ubi_avlInsert( ubi_btRootPtr RootPtr, - ubi_btNodePtr NewNode, - ubi_btItemPtr ItemPtr, - ubi_btNodePtr *OldNode ); - /* ------------------------------------------------------------------------ ** - * This function uses a non-recursive algorithm to add a new element to - * the tree. - * - * Input: RootPtr - a pointer to the ubi_btRoot structure that indicates - * the root of the tree to which NewNode is to be added. - * NewNode - a pointer to an ubi_btNode structure that is NOT - * part of any tree. - * ItemPtr - A pointer to the sort key that is stored within - * *NewNode. ItemPtr MUST point to information stored - * in *NewNode or an EXACT DUPLICATE. The key data - * indicated by ItemPtr is used to place the new node - * into the tree. - * OldNode - a pointer to an ubi_btNodePtr. When searching - * the tree, a duplicate node may be found. If - * duplicates are allowed, then the new node will - * be simply placed into the tree. If duplicates - * are not allowed, however, then one of two things - * may happen. - * 1) if overwritting *is not* allowed, this - * function will return FALSE (indicating that - * the new node could not be inserted), and - * *OldNode will point to the duplicate that is - * still in the tree. - * 2) if overwritting *is* allowed, then this - * function will swap **OldNode for *NewNode. - * In this case, *OldNode will point to the node - * that was removed (thus allowing you to free - * the node). - * ** If you are using overwrite mode, ALWAYS ** - * ** check the return value of this parameter! ** - * Note: You may pass NULL in this parameter, the - * function knows how to cope. If you do this, - * however, there will be no way to return a - * pointer to an old (ie. replaced) node (which is - * a problem if you are using overwrite mode). - * - * Output: a boolean value indicating success or failure. The function - * will return FALSE if the node could not be added to the tree. - * Such failure will only occur if duplicates are not allowed, - * nodes cannot be overwritten, AND a duplicate key was found - * within the tree. - * ------------------------------------------------------------------------ ** - */ - -ubi_btNodePtr ubi_avlRemove( ubi_btRootPtr RootPtr, - ubi_btNodePtr DeadNode ); - /* ------------------------------------------------------------------------ ** - * This function removes the indicated node from the tree, after which the - * tree is rebalanced. - * - * Input: RootPtr - A pointer to the header of the tree that contains - * the node to be removed. - * DeadNode - A pointer to the node that will be removed. - * - * Output: This function returns a pointer to the node that was removed - * from the tree (ie. the same as DeadNode). - * - * Note: The node MUST be in the tree indicated by RootPtr. If not, - * strange and evil things will happen to your trees. - * ------------------------------------------------------------------------ ** - */ - -int ubi_avlModuleID( int size, char *list[] ); - /* ------------------------------------------------------------------------ ** - * Returns a set of strings that identify the module. - * - * Input: size - The number of elements in the array <list>. - * list - An array of pointers of type (char *). This array - * should, initially, be empty. This function will fill - * in the array with pointers to strings. - * Output: The number of elements of <list> that were used. If this value - * is less than <size>, the values of the remaining elements are - * not guaranteed. - * - * Notes: Please keep in mind that the pointers returned indicate strings - * stored in static memory. Don't free() them, don't write over - * them, etc. Just read them. - * ------------------------------------------------------------------------ ** - */ - -/* -------------------------------------------------------------------------- ** - * Masquarade... - * - * This set of defines allows you to write programs that will use any of the - * implemented binary tree modules (currently BinTree, AVLtree, and SplayTree). - * Instead of using ubi_avl... or ubi_bt, use ubi_tr... and select the tree - * type by including the appropriate module header. - */ - -#undef ubi_trInsert -#define ubi_trInsert( Rp, Nn, Ip, On ) \ - ubi_avlInsert( (ubi_btRootPtr)(Rp), (ubi_btNodePtr)(Nn), \ - (ubi_btItemPtr)(Ip), (ubi_btNodePtr *)(On) ) - -#undef ubi_trRemove -#define ubi_trRemove( Rp, Dn ) \ - ubi_avlRemove( (ubi_btRootPtr)(Rp), (ubi_btNodePtr)(Dn) ) - -#undef ubi_trModuleID -#define ubi_trModuleID( s, l ) ubi_avlModuleID( s, l ) - - -/* =========================== End ubi_AVLtree.h =========================== */ -#endif /* ubi_AVLtree_H */ |