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-/* ========================================================================== **
- * ubi_AVLtree.c
- *
- * Copyright (C) 1991-1997 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 1.1 1997/10/09 04:09:51 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 2.4 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_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
- *
- * V0.0 - May, 1990 - Written by Christopher R. Hertel (CRH).
- *
- * ========================================================================= **
- */
-
-#include "ubi_AVLtree.h" /* Header for THIS module. */
-#include <stdlib.h> /* Standard C definitions, etc. */
-
-/* ========================================================================== **
- * Static data.
- */
-
-static char ModuleID[] = "ubi_AVLtree\n\
-\t$Revision: 1.1 $\n\
-\t$Date: 1997/10/09 04:09:51 $\n\
-\t$Author: 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_avlNodePtr L1( ubi_avlNodePtr 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_avlNodePtr tmp;
-
- tmp = p->Link[RIGHT];
- p->Link[RIGHT] = tmp->Link[LEFT];
- tmp->Link[LEFT] = p;
-
- tmp->Link[PARENT] = p->Link[PARENT];
- tmp->gender = p->gender;
- if(tmp->Link[PARENT])
- (tmp->Link[PARENT])->Link[(tmp->gender)] = tmp;
- p->Link[PARENT] = tmp;
- p->gender = LEFT;
- if( p->Link[RIGHT] )
- {
- p->Link[RIGHT]->Link[PARENT] = p;
- (p->Link[RIGHT])->gender = RIGHT;
- }
- p->balance -= Normalize( tmp->balance );
- (tmp->balance)--;
- return( tmp );
- } /* L1 */
-
-static ubi_avlNodePtr R1( ubi_avlNodePtr 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_avlNodePtr tmp;
-
- tmp = p->Link[LEFT];
- p->Link[LEFT] = tmp->Link[RIGHT];
- tmp->Link[RIGHT] = p;
-
- tmp->Link[PARENT] = p->Link[PARENT];
- tmp->gender = p->gender;
- if(tmp->Link[PARENT])
- (tmp->Link[PARENT])->Link[(tmp->gender)] = tmp;
- p->Link[PARENT] = tmp;
- p->gender = RIGHT;
- if(p->Link[LEFT])
- {
- p->Link[LEFT]->Link[PARENT] = p;
- p->Link[LEFT]->gender = LEFT;
- }
- p->balance -= Normalize( tmp->balance );
- (tmp->balance)++;
- return( tmp );
- } /* R1 */
-
-static ubi_avlNodePtr L2( ubi_avlNodePtr 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_avlNodePtr tmp, newroot;
-
- tmp = tree->Link[RIGHT];
- newroot = tmp->Link[LEFT];
- tmp->Link[LEFT] = newroot->Link[RIGHT];
- newroot->Link[RIGHT] = tmp;
- tree->Link[RIGHT] = newroot->Link[LEFT];
- newroot->Link[LEFT] = tree;
-
- newroot->Link[PARENT] = tree->Link[PARENT];
- newroot->gender = tree->gender;
- tree->Link[PARENT] = newroot;
- tree->gender = LEFT;
- tmp->Link[PARENT] = newroot;
- tmp->gender = RIGHT;
-
- if( tree->Link[RIGHT] )
- {
- tree->Link[RIGHT]->Link[PARENT] = tree;
- tree->Link[RIGHT]->gender = RIGHT;
- }
- if( tmp->Link[LEFT] )
- {
- tmp->Link[LEFT]->Link[PARENT] = tmp;
- tmp->Link[LEFT]->gender = LEFT;
- }
- if(newroot->Link[PARENT])
- newroot->Link[PARENT]->Link[newroot->gender] = newroot;
-
- switch( newroot->balance )
- {
- case LEFT :
- tree->balance = EQUAL; tmp->balance = RIGHT; break;
- case EQUAL:
- tree->balance = EQUAL; tmp->balance = EQUAL; break;
- case RIGHT:
- tree->balance = LEFT; tmp->balance = EQUAL; break;
- }
- newroot->balance = EQUAL;
- return( newroot );
- } /* L2 */
-
-static ubi_avlNodePtr R2( ubi_avlNodePtr 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_avlNodePtr tmp, newroot;
-
- tmp = tree->Link[LEFT];
- newroot = tmp->Link[RIGHT];
- tmp->Link[RIGHT] = newroot->Link[LEFT];
- newroot->Link[LEFT] = tmp;
- tree->Link[LEFT] = newroot->Link[RIGHT];
- newroot->Link[RIGHT] = tree;
-
- newroot->Link[PARENT] = tree->Link[PARENT];
- newroot->gender = tree->gender;
- tree->Link[PARENT] = newroot;
- tree->gender = RIGHT;
- tmp->Link[PARENT] = newroot;
- tmp->gender = LEFT;
-
- if( tree->Link[LEFT] )
- {
- tree->Link[LEFT]->Link[PARENT] = tree;
- tree->Link[LEFT]->gender = LEFT;
- }
- if( tmp->Link[RIGHT] )
- {
- tmp->Link[RIGHT]->Link[PARENT] = tmp;
- tmp->Link[RIGHT]->gender = RIGHT;
- }
- if(newroot->Link[PARENT])
- newroot->Link[PARENT]->Link[newroot->gender] = newroot;
-
- switch( newroot->balance )
- {
- case LEFT :
- tree->balance = RIGHT; tmp->balance = EQUAL; break;
- case EQUAL :
- tree->balance = EQUAL; tmp->balance = EQUAL; break;
- case RIGHT :
- tree->balance = EQUAL; tmp->balance = LEFT; break;
- }
- newroot->balance = EQUAL;
- return( newroot );
- } /* R2 */
-
-
-static ubi_avlNodePtr Adjust( ubi_avlNodePtr 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 += Normalize(LorR);
- else
- {
- char tallerbal; /* Balance value of the root of the taller subtree of p. */
-
- tallerbal = p->Link[LorR]->balance;
- if( ( EQUAL == tallerbal ) || ( p->balance == tallerbal ) )
- p = ( (LEFT==LorR) ? R1(p) : L1(p) ); /* single rotation */
- else
- p = ( (LEFT==LorR) ? R2(p) : L2(p) ); /* double rotation */
- }
- return( p );
- } /* Adjust */
-
-static ubi_avlNodePtr Rebalance( ubi_avlNodePtr Root,
- ubi_avlNodePtr 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( PARENT == subtree->gender )
- return( subtree );
- if( EQUAL == subtree->balance )
- return( Root );
- LorR = subtree->gender;
- subtree = subtree->Link[PARENT];
- }
- return( Root );
- } /* Rebalance */
-
-static ubi_avlNodePtr Debalance( ubi_avlNodePtr Root,
- ubi_avlNodePtr 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, RevWay(LorR) );
- if( PARENT == subtree->gender )
- return( subtree );
- if( EQUAL != subtree->balance )
- return( Root );
- LorR = subtree->gender;
- subtree = subtree->Link[PARENT];
- }
- return( Root );
- } /* Debalance */
-
-
-/* -------------------------------------------------------------------------- **
- * The next two functions are used for general tree manipulation. They are
- * each slightly different from their ubi_BinTree counterparts.
- * -------------------------------------------------------------------------- **
- */
-
-static void ReplaceNode( ubi_avlNodePtr *parent,
- ubi_avlNodePtr oldnode,
- ubi_avlNodePtr newnode )
- /* ------------------------------------------------------------------------ **
- * Remove node oldnode from the tree, replacing it with node newnode.
- *
- * Input:
- * parent - A pointer to he parent pointer of the node to be
- * replaced. <parent> may point to the Link[] field of
- * a parent node, or it may indicate the root pointer at
- * the top of the tree.
- * oldnode - A pointer to the node that is to be replaced.
- * newnode - A pointer to the node that is to be installed in the
- * place of <*oldnode>.
- *
- * Notes: Don't forget to free oldnode.
- * The only difference between this function and the ubi_bt
- * version is that the node size is sizeof( ubi_avlNode ), not
- * sizeof( ubi_btNode ).
- * ------------------------------------------------------------------------ **
- */
- {
- register int i;
- register int avlNodeSize = sizeof( ubi_avlNode );
-
- for( i = 0; i < avlNodeSize; i++ )
- ((unsigned char *)newnode)[i] = ((unsigned char *)oldnode)[i];
- (*parent) = newnode;
-
- if(oldnode->Link[LEFT ] )
- (oldnode->Link[LEFT ])->Link[PARENT] = newnode;
- if(oldnode->Link[RIGHT] )
- (oldnode->Link[RIGHT])->Link[PARENT] = newnode;
- } /* ReplaceNode */
-
-static void SwapNodes( ubi_btRootPtr RootPtr,
- ubi_avlNodePtr Node1,
- ubi_avlNodePtr Node2 )
- /* ------------------------------------------------------------------------ **
- * This function swaps two nodes in the tree. Node1 will take the place of
- * Node2, and Node2 will fill in the space left vacant by Node 1.
- *
- * Input:
- * RootPtr - pointer to the tree header structure for this tree.
- * Node1 - \
- * > These are the two nodes which are to be swapped.
- * Node2 - /
- *
- * Notes:
- * This function does a three step swap, using a dummy node as a place
- * holder. This function is used by ubi_avlRemove().
- * The only difference between this function and its ubi_bt counterpart
- * is that the nodes are ubi_avlNodes, not ubi_btNodes.
- * ------------------------------------------------------------------------ **
- */
- {
- ubi_avlNodePtr *Parent;
- ubi_avlNode dummy;
- ubi_avlNodePtr dummy_p = &dummy;
-
- if( Node1->Link[PARENT] )
- Parent = &((Node1->Link[PARENT])->Link[Node1->gender]);
- else
- Parent = (ubi_avlNodePtr *)&(RootPtr->root);
- ReplaceNode( Parent, Node1, dummy_p );
-
- if( Node2->Link[PARENT] )
- Parent = &((Node2->Link[PARENT])->Link[Node2->gender]);
- else
- Parent = (ubi_avlNodePtr *)&(RootPtr->root);
- ReplaceNode( Parent, Node2, Node1 );
-
- if( dummy_p->Link[PARENT] )
- Parent = &((dummy_p->Link[PARENT])->Link[dummy_p->gender]);
- else
- Parent = (ubi_avlNodePtr *)&(RootPtr->root);
- ReplaceNode( Parent, dummy_p, Node2 );
- } /* SwapNodes */
-
-
-/* ========================================================================== **
- * Public, exported (ie. not static-ly declared) functions...
- * -------------------------------------------------------------------------- **
- */
-
-ubi_avlNodePtr ubi_avlInitNode( ubi_avlNodePtr NodePtr )
- /* ------------------------------------------------------------------------ **
- * Initialize a tree node.
- *
- * Input: NodePtr - pointer to a ubi_btNode structure to be
- * initialized.
- * Output: a pointer to the initialized ubi_avlNode structure (ie. the
- * same as the input pointer).
- * ------------------------------------------------------------------------ **
- */
- {
- (void)ubi_btInitNode( (ubi_btNodePtr)NodePtr );
- NodePtr->balance = EQUAL;
- return( NodePtr );
- } /* ubi_avlInitNode */
-
-ubi_trBool ubi_avlInsert( ubi_btRootPtr RootPtr,
- ubi_avlNodePtr NewNode,
- ubi_btItemPtr ItemPtr,
- ubi_avlNodePtr *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_avlNode 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_avlNodePtr 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 = EQUAL;
- RootPtr->root = (ubi_btNodePtr)Rebalance( (ubi_avlNodePtr)RootPtr->root,
- NewNode->Link[PARENT],
- NewNode->gender );
- }
- return( ubi_trTRUE );
- }
- return( ubi_trFALSE ); /* Failure: could not replace an existing node. */
- } /* ubi_avlInsert */
-
-ubi_avlNodePtr ubi_avlRemove( ubi_btRootPtr RootPtr,
- ubi_avlNodePtr 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.
- * ------------------------------------------------------------------------ **
- */
- {
- ubi_btNodePtr p,
- *parentp;
-
- /* if the node has both left and right subtrees, then we have to swap
- * it with another node.
- */
- if( (DeadNode->Link[LEFT]) && (DeadNode->Link[RIGHT]) )
- SwapNodes( RootPtr, DeadNode, ubi_trPrev( DeadNode ) );
-
- /* The parent of the node to be deleted may be another node, or it may be
- * the root of the tree. Since we're not sure, it's best just to have
- * a pointer to the parent pointer, whatever it is.
- */
- if( DeadNode->Link[PARENT] )
- parentp = (ubi_btNodePtr *)
- &((DeadNode->Link[PARENT])->Link[(DeadNode->gender)]);
- else
- parentp = &( RootPtr->root );
-
- /* Now link the parent to the only grand-child. Patch up the gender and
- * such, and rebalance.
- */
- if( EQUAL == DeadNode->balance )
- (*parentp) = NULL;
- else
- {
- p = (ubi_btNodePtr)(DeadNode->Link[(DeadNode->balance)]);
- p->Link[PARENT] = (ubi_btNodePtr)DeadNode->Link[PARENT];
- p->gender = DeadNode->gender;
- (*parentp) = p;
- }
- RootPtr->root = (ubi_btNodePtr)Debalance( (ubi_avlNodePtr)RootPtr->root,
- DeadNode->Link[PARENT],
- DeadNode->gender );
-
- (RootPtr->count)--;
- 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 ============================== */