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diff --git a/source3/ubi_SplayTree.h b/source3/ubi_SplayTree.h new file mode 100644 index 0000000000..6a17a19ec4 --- /dev/null +++ b/source3/ubi_SplayTree.h @@ -0,0 +1,339 @@ +#ifndef ubi_SplayTree_H +#define ubi_SplayTree_H +/* ========================================================================== ** + * ubi_SplayTree.h + * + * Copyright (C) 1993,1995 by Christopher R. Hertel + * + * Email: crh@ubiqx.mn.org + * -------------------------------------------------------------------------- ** + * + * This module implements "splay" trees. Splay trees are binary trees + * that are rearranged (splayed) whenever a node is accessed. The + * splaying process *tends* to make the tree bushier (improves balance), + * and the nodes that are accessed most frequently *tend* to be closer to + * the top. + * + * References: "Self-Adjusting Binary Search Trees", by Daniel Sleator and + * Robert Tarjan. Journal of the Association for Computing + * Machinery Vol 32, No. 3, July 1985 pp. 652-686 + * + * -------------------------------------------------------------------------- ** + * + * 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_SplayTree.h,v $ + * Revision 1.1 1997/10/09 04:09:55 crh + * This is my library of lists and trees. My hope is to replace all of the + * hard coded linked lists that are currently used in Samba with calls to + * these modules. This should make the code simpler, smaller, and (I hope) + * faster. The tree code, in particular, should speed up processing where + * large lists are involved. + * + * Chris -)----- + * + * Revision 2.5 1997/07/26 04:15:46 crh + * + Cleaned up a few minor syntax annoyances that gcc discovered for me. + * + Changed ubi_TRUE and ubi_FALSE to ubi_trTRUE and ubi_trFALSE. + * + * Revision 2.4 1997/06/03 05:22:56 crh + * Changed TRUE and FALSE to ubi_TRUE and ubi_FALSE to avoid causing + * problems. + * + * Revision 2.3 1995/10/03 22:19:37 CRH + * Ubisized! + * Also, added the function ubi_sptSplay(). + * + * Revision 2.1 95/03/09 23:55:04 CRH + * Added the ModuleID static string and function. These modules are now + * self-identifying. + * + * Revision 2.0 95/02/27 22:34:55 CRH + * This module was updated to match the interface changes made to the + * ubi_BinTree module. In particular, the interface to the Locate() function + * has changed. See ubi_BinTree for more information on changes and new + * functions. + * + * The revision number was also upped to match ubi_BinTree. + * + * + * Revision 1.0 93/10/15 22:59:36 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_AVLtree, the AVL node structure was + * named "ubi_avlNode", but the root structure was still "ubi_btRoot". Using + * 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 + * + * Revision 0.0 93/04/21 23:07:13 CRH + * Initial version, written by Christopher R. Hertel. + * This module implements Splay Trees using the ubi_BinTree module as a basis. + * + * ========================================================================== ** + */ + +#include "ubi_BinTree.h" /* Base binary tree functions, types, etc. */ + +/* ========================================================================== ** + * Function prototypes... + */ + +ubi_trBool ubi_sptInsert( 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 + * splay 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_sptRemove( ubi_btRootPtr RootPtr, ubi_btNodePtr DeadNode ); + /* ------------------------------------------------------------------------ ** + * This function removes the indicated node from the tree. + * + * 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. + * ------------------------------------------------------------------------ ** + */ + +ubi_btNodePtr ubi_sptLocate( ubi_btRootPtr RootPtr, + ubi_btItemPtr FindMe, + ubi_trCompOps CompOp ); + /* ------------------------------------------------------------------------ ** + * The purpose of ubi_btLocate() is to find a node or set of nodes given + * a target value and a "comparison operator". The Locate() function is + * more flexible and (in the case of trees that may contain dupicate keys) + * more precise than the ubi_btFind() function. The latter is faster, + * but it only searches for exact matches and, if the tree contains + * duplicates, Find() may return a pointer to any one of the duplicate- + * keyed records. + * + * Input: + * RootPtr - A pointer to the header of the tree to be searched. + * FindMe - An ubi_btItemPtr that indicates the key for which to + * search. + * CompOp - One of the following: + * CompOp Return a pointer to the node with + * ------ --------------------------------- + * ubi_trLT - the last key value that is less + * than FindMe. + * ubi_trLE - the first key matching FindMe, or + * the last key that is less than + * FindMe. + * ubi_trEQ - the first key matching FindMe. + * ubi_trGE - the first key matching FindMe, or the + * first key greater than FindMe. + * ubi_trGT - the first key greater than FindMe. + * Output: + * A pointer to the node matching the criteria listed above under + * CompOp, or NULL if no node matched the criteria. + * + * Notes: + * In the case of trees with duplicate keys, Locate() will behave as + * follows: + * + * Find: 3 Find: 3 + * Keys: 1 2 2 2 3 3 3 3 3 4 4 Keys: 1 1 2 2 2 4 4 5 5 5 6 + * ^ ^ ^ ^ ^ + * LT EQ GT LE GE + * + * That is, when returning a pointer to a node with a key that is LESS + * THAN the target key (FindMe), Locate() will return a pointer to the + * LAST matching node. + * When returning a pointer to a node with a key that is GREATER + * THAN the target key (FindMe), Locate() will return a pointer to the + * FIRST matching node. + * + * See Also: ubi_btFind(), ubi_btFirstOf(), ubi_btLastOf(). + * ------------------------------------------------------------------------ ** + */ + +ubi_btNodePtr ubi_sptFind( ubi_btRootPtr RootPtr, + ubi_btItemPtr FindMe ); + /* ------------------------------------------------------------------------ ** + * This function performs a non-recursive search of a tree for any node + * matching a specific key. + * + * Input: + * RootPtr - a pointer to the header of the tree to be searched. + * FindMe - a pointer to the key value for which to search. + * + * Output: + * A pointer to a node with a key that matches the key indicated by + * FindMe, or NULL if no such node was found. + * + * Note: In a tree that allows duplicates, the pointer returned *might + * not* point to the (sequentially) first occurance of the + * desired key. In such a tree, it may be more useful to use + * ubi_sptLocate(). + * ------------------------------------------------------------------------ ** + */ + +void ubi_sptSplay( ubi_btRootPtr RootPtr, + ubi_btNodePtr SplayMe ); + /* ------------------------------------------------------------------------ ** + * This function allows you to splay the tree at a given node, thus moving + * the node to the top of the tree. + * + * Input: + * RootPtr - a pointer to the header of the tree to be splayed. + * SplayMe - a pointer to a node within the tree. This will become + * the new root node. + * Output: None. + * + * Notes: This is an uncharacteristic function for this group of modules + * in that it provides access to the internal balancing routines, + * which would normally be hidden. + * Splaying the tree will not damage it (assuming that I've done + * *my* job), but there is overhead involved. I don't recommend + * that you use this function unless you understand the underlying + * Splay Tree principles involved. + * ------------------------------------------------------------------------ ** + */ + +int ubi_sptModuleID( 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_bt..., use ubi_tr..., and select the tree type by + * including the appropriate module header. + */ + +#undef ubi_trInsert +#undef ubi_trRemove +#undef ubi_trLocate +#undef ubi_trFind +#undef ubi_trModuleID + +#define ubi_trInsert( Rp, Nn, Ip, On ) \ + ubi_sptInsert( (ubi_btRootPtr)(Rp), (ubi_btNodePtr)(Nn), \ + (ubi_btItemPtr)(Ip), (ubi_btNodePtr *)(On) ) + +#define ubi_trRemove( Rp, Dn ) \ + ubi_sptRemove( (ubi_btRootPtr)(Rp), (ubi_btNodePtr)(Dn) ) + +#define ubi_trLocate( Rp, Ip, Op ) \ + ubi_sptLocate( (ubi_btRootPtr)(Rp), \ + (ubi_btItemPtr)(Ip), \ + (ubi_trCompOps)(Op) ) + +#define ubi_trFind( Rp, Ip ) \ + ubi_sptFind( (ubi_btRootPtr)(Rp), (ubi_btItemPtr)(Ip) ) + +#define ubi_trModuleID( s, l ) ubi_sptModuleID( s, l ) + +/* ================================ The End ================================= */ +#endif /* ubi_SplayTree_H */ + + + + + |