This is the ubiqx binary tree and linked list library.

This library is being included as part of the Samba distribution.
(Hurray!)
(This used to be commit 3590a783338defa4ff1385b2d5bb095c5051ac82)

1 files changed, 1038 insertions, 0 deletions

diff --git a/source3/ubiqx/ubi_BinTree.c b/source3/ubiqx/ubi_BinTree.c
new file mode 100644
index 0000000000..dc72f9bad3
--- /dev/null
+++ b/source3/ubiqx/ubi_BinTree.c
@@ -0,0 +1,1038 @@
+/* ========================================================================== **
+ *                              ubi_BinTree.c
+ *
+ *  Copyright (C) 1991-1997 by Christopher R. Hertel
+ *
+ *  Email:  crh@ubiqx.mn.org
+ * -------------------------------------------------------------------------- **
+ *
+ *  ubi_BinTree manages a simple binary tree.  Nothing fancy here.  No height
+ *  balancing, no restructuring.  Still, a good tool for creating short, low-
+ *  overhead sorted lists of things that need to be found in a hurry.
+ *
+ *  In addition, this module provides a good basis for creating other types
+ *  of binary tree handling modules.
+ *
+ * -------------------------------------------------------------------------- **
+ *
+ *  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_BinTree.c,v $
+ * Revision 1.1  1997/10/10 14:46:38  crh
+ * This is the ubiqx binary tree and linked list library.
+ * This library is being included as part of the Samba distribution.
+ * (Hurray!)
+ *
+ * Revision 2.4  1997/07/26 04:11:10  crh
+ * + Just to be annoying I changed ubi_TRUE and ubi_FALSE to ubi_trTRUE
+ *   and ubi_trFALSE.
+ * + There is now a type ubi_trBool to go with ubi_trTRUE and ubi_trFALSE.
+ * + There used to be something called "ubi_TypeDefs.h".  I got rid of it.
+ * + Added function ubi_btLeafNode().
+ *
+ * Revision 2.3  1997/06/03 05:16:17  crh
+ * Changed TRUE and FALSE to ubi_TRUE and ubi_FALSE to avoid conflicts.
+ * Also changed the interface to function InitTree().  See the comments
+ * for this function for more information.
+ *
+ * Revision 2.2  1995/10/03 22:00:07  CRH
+ * Ubisized!
+ * 
+ * Revision 2.1  95/03/09  23:37:10  CRH
+ * Added the ModuleID static string and function.  These modules are now
+ * self-identifying.
+ * 
+ * Revision 2.0  95/02/27  22:00:17  CRH
+ * Revision 2.0 of this program includes the following changes:
+ *
+ *     1)  A fix to a major typo in the RepaceNode() function.
+ *     2)  The addition of the static function Border().
+ *     3)  The addition of the public functions FirstOf() and LastOf(), which
+ *         use Border(). These functions are used with trees that allow
+ *         duplicate keys.
+ *     4)  A complete rewrite of the Locate() function.  Locate() now accepts
+ *         a "comparison" operator.
+ *     5)  Overall enhancements to both code and comments.
+ *
+ * I decided to give this a new major rev number because the interface has
+ * changed.  In particular, there are two new functions, and changes to the
+ * Locate() function.
+ *
+ * Revision 1.0  93/10/15  22:44:59  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 - June, 1991   -  Written by Christopher R. Hertel (CRH).
+ *
+ * ========================================================================== **
+ */
+
+#include "ubi_BinTree.h"            /* Header for this module          */
+#include <stdlib.h>                 /* Standard C definitions.         */
+
+/* ========================================================================== **
+ * Static data.
+ */
+
+static char ModuleID[] = "ubi_BinTree\n\
+\t$Revision: 1.1 $\n\
+\t$Date: 1997/10/10 14:46:38 $\n\
+\t$Author: crh $\n";
+
+/* ========================================================================== **
+ * Internal (private) functions.
+ */
+
+static ubi_btNodePtr qFind( ubi_btCompFunc cmp,
+                            ubi_btItemPtr  FindMe,
+                   register ubi_btNodePtr  p )
+  /* ------------------------------------------------------------------------ **
+   * This function performs a non-recursive search of a tree for a node
+   * matching a specific key.  It is called "qFind()" because it is
+   * faster that TreeFind (below).
+   *
+   *  Input:
+   *     cmp      -  a pointer to the tree's comparison function.
+   *     FindMe   -  a pointer to the key value for which to search.
+   *     p        -  a pointer to the starting point of the search.  <p>
+   *                 is considered to be the root of a subtree, and only
+   *                 the subtree will be searched.
+   *
+   *  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.
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  char tmp;
+
+  while( p && (( tmp = AbNormal((*cmp)(FindMe, p)) ) != EQUAL) )
+    p = p->Link[tmp];
+
+  return( p );
+  } /* qFind */
+
+static ubi_btNodePtr TreeFind( ubi_btItemPtr  findme,
+                               ubi_btNodePtr  p,
+                               ubi_btNodePtr *parentp,
+                               char          *gender,
+                               ubi_btCompFunc CmpFunc )
+  /* ------------------------------------------------------------------------ **
+   * TreeFind() searches a tree for a given value (findme).  It will return a
+   * pointer to the target node, if found, or NULL if the target node was not
+   * found.
+   *
+   * TreeFind() also returns, via parameters, a pointer to the parent of the
+   * target node, and a LEFT or RIGHT value indicating which child of the
+   * parent is the target node.  *If the target is not found*, then these
+   * values indicate the place at which the target *should be found*.  This
+   * is useful when inserting a new node into a tree or searching for nodes
+   * "near" the target node.
+   *
+   * The parameters are:
+   *
+   *  findme   -  is a pointer to the key information to be searched for.
+   *  p        -  points to the root of the tree to be searched.
+   *  parentp  -  will return a pointer to a pointer to the !parent! of the
+   *              target node, which can be especially usefull if the target
+   *              was not found.
+   *  gender   -  returns LEFT or RIGHT to indicate which child of *parentp
+   *              was last searched.
+   *  CmpFunc  -  points to the comparison function.
+   *
+   * This function is called by ubi_btLocate() and ubi_btInsert().
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  register ubi_btNodePtr tmp_p = p;
+  ubi_btNodePtr tmp_pp = NULL;
+  char tmp_sex = EQUAL;
+  char tmp_cmp;
+
+  while( tmp_p && (EQUAL != (tmp_cmp = AbNormal((*CmpFunc)(findme, tmp_p)))) )
+    {
+    tmp_pp  = tmp_p;                /* Keep track of previous node. */
+    tmp_sex = tmp_cmp;              /* Keep track of sex of child.  */
+    tmp_p = tmp_p->Link[tmp_cmp];   /* Go to child. */
+    }
+  *parentp = tmp_pp;                /* Return results. */
+  *gender  = tmp_sex;
+  return( tmp_p );
+  } /* TreeFind */
+
+static void ReplaceNode( ubi_btNodePtr *parent,
+                         ubi_btNodePtr  oldnode,
+                         ubi_btNodePtr  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.
+   *           Also, this function used to have a really nasty typo
+   *           bug.  "oldnode" and "newnode" were swapped in the line
+   *           that now reads:
+   *     ((unsigned char *)newnode)[i] = ((unsigned char *)oldnode)[i];
+   *           Bleah!
+   * ------------------------------------------------------------------ *
+   */
+  {
+  register int i;
+  register int btNodeSize = sizeof( ubi_btNode );
+
+  for( i = 0; i < btNodeSize; i++ ) /* Copy node internals to new node. */
+    ((unsigned char *)newnode)[i] = ((unsigned char *)oldnode)[i];
+  (*parent) = newnode;              /* Old node's parent points to new child. */
+  /* Now tell the children about their new step-parent. */
+  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_btNodePtr Node1,
+                       ubi_btNodePtr 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_btRemove().
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  ubi_btNodePtr *Parent;
+  ubi_btNode     dummy;
+  ubi_btNodePtr  dummy_p = &dummy;
+
+  /* Replace Node 1 with the dummy, thus removing Node1 from the tree. */
+  if( Node1->Link[PARENT] )
+    Parent = &((Node1->Link[PARENT])->Link[Node1->gender]);
+  else
+    Parent = &(RootPtr->root);
+  ReplaceNode( Parent, Node1, dummy_p );
+
+  /* Swap Node 1 with Node 2, placing Node 1 back into the tree. */
+  if( Node2->Link[PARENT] )
+    Parent = &((Node2->Link[PARENT])->Link[Node2->gender]);
+  else
+    Parent = &(RootPtr->root);
+  ReplaceNode( Parent, Node2, Node1 );
+
+  /* Swap Node 2 and the dummy, thus placing Node 2 back into the tree. */
+  if( dummy_p->Link[PARENT] )
+    Parent = &((dummy_p->Link[PARENT])->Link[dummy_p->gender]);
+  else
+    Parent = &(RootPtr->root);
+  ReplaceNode( Parent, dummy_p, Node2 );
+  } /* SwapNodes */
+
+/* -------------------------------------------------------------------------- **
+ * These routines allow you to walk through the tree, forwards or backwards.
+ */
+
+static ubi_btNodePtr SubSlide( register ubi_btNodePtr P,
+                               register char  whichway )
+  /* ------------------------------------------------------------------------ **
+   * Slide down the side of a subtree.
+   *
+   * Given a starting node, this function returns a pointer to the LEFT-, or
+   * RIGHT-most descendent, *or* (if whichway is PARENT) to the tree root.
+   *
+   *  Input:  P         - a pointer to a starting place.
+   *          whichway  - the direction (LEFT, RIGHT, or PARENT) in which to
+   *                      travel.
+   *  Output: A pointer to a node that is either the root, or has no
+   *          whichway-th child but is within the subtree of P.  Note that
+   *          the return value may be the same as P.  The return value *will
+   *          be* NULL if P is NULL.
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  ubi_btNodePtr Q = NULL;
+
+  while( P )
+    {
+    Q = P;
+    P = P->Link[ whichway ];
+    }
+  return( Q );
+  } /* SubSlide */
+
+static ubi_btNodePtr Neighbor( register ubi_btNodePtr P,
+                               register char  whichway )
+  /* ------------------------------------------------------------------------ **
+   * Given starting point p, return the (key order) next or preceeding node
+   * in the tree.
+   *
+   *  Input:  P         - Pointer to our starting place node.
+   *          whichway  - the direction in which to travel to find the
+   *                      neighbor, i.e., the RIGHT neighbor or the LEFT
+   *                      neighbor.
+   *
+   *  Output: A pointer to the neighboring node, or NULL if P was NULL.
+   *
+   *  Notes:  If whichway is PARENT, the results are unpredictable.
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  if( P )
+    {
+    if( P->Link[ whichway ] )
+      return( SubSlide( P->Link[ whichway ], (char)RevWay(whichway) ) );
+    else
+      while( P->Link[ PARENT ] )
+        {
+        if( (P->Link[ PARENT ])->Link[ whichway ] == P )
+          P = P->Link[ PARENT ];
+        else
+          return( P->Link[ PARENT ] );
+        }
+    }
+  return( NULL );
+  } /* Neighbor */
+
+static ubi_btNodePtr Border( ubi_btRootPtr RootPtr,
+                             ubi_btItemPtr FindMe,
+                             ubi_btNodePtr p,
+                             char          whichway )
+  /* ------------------------------------------------------------------------ **
+   * Given starting point p, which has a key value equal to *FindMe, locate
+   * the first (index order) node with the same key value.
+   *
+   * This function is useful in trees that have can have duplicate keys.
+   * For example, consider the following tree:
+   *     Tree                                                      Traversal
+   *       2    If <p> points to the root and <whichway> is RIGHT,     3
+   *      / \    then the return value will be a pointer to the       / \
+   *     2   2    RIGHT child of the root node.  The tree on         2   5
+   *    /   / \    the right shows the order of traversal.          /   / \
+   *   1   2   3                                                   1   4   6
+   *
+   *  Input:  RootPtr   - Pointer to the tree root structure.
+   *          FindMe    - Key value for comparisons.
+   *          p         - Pointer to the starting-point node.
+   *          whichway  - the direction in which to travel to find the
+   *                      neighbor, i.e., the RIGHT neighbor or the LEFT
+   *                      neighbor.
+   *
+   *  Output: A pointer to the first (index, or "traversal", order) node with
+   *          a Key value that matches *FindMe.
+   *
+   *  Notes:  If whichway is PARENT, or if the tree does not allow duplicate
+   *          keys, this function will return <p>.
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  register ubi_btNodePtr q;
+
+  /* Exit if there's nothing that can be done. */
+  if( !Dups_OK( RootPtr ) || (PARENT == whichway) )
+    return( p );
+
+  /* First, if needed, move up the tree.  We need to get to the root of the
+   * subtree that contains all of the matching nodes.
+   */
+  q = p->Link[PARENT];
+  while( q && (EQUAL == AbNormal( (*(RootPtr->cmp))(FindMe, q) )) )
+    {
+    p = q;
+    q = p->Link[PARENT];
+    }
+
+  /* Next, move back down in the "whichway" direction. */
+  q = p->Link[whichway];
+  while( q )
+    {
+    if( q = qFind( RootPtr->cmp, FindMe, q ) )
+      {
+      p = q;
+      q = p->Link[whichway];
+      }
+    }
+  return( p );
+  } /* Border */
+
+
+/* ========================================================================== **
+ * Exported utilities.
+ */
+
+long ubi_btSgn( register long x )
+  /* ------------------------------------------------------------------------ **
+   * Return the sign of x; {negative,zero,positive} ==> {-1, 0, 1}.
+   *
+   *  Input:  x - a signed long integer value.
+   *
+   *  Output: the "sign" of x, represented as follows:
+   *            -1 == negative
+   *             0 == zero (no sign)
+   *             1 == positive
+   *
+   * Note: This utility is provided in order to facilitate the conversion
+   *       of C comparison function return values into BinTree direction
+   *       values: {LEFT, PARENT, EQUAL}.  It is INCORPORATED into the
+   *       AbNormal() conversion macro!
+   *
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  return( (x)?((x>0)?(1):(-1)):(0) );
+  } /* ubi_btSgn */
+
+ubi_btNodePtr ubi_btInitNode( ubi_btNodePtr NodePtr )
+  /* ------------------------------------------------------------------------ **
+   * Initialize a tree node.
+   *
+   *  Input:  a pointer to a ubi_btNode structure to be initialized.
+   *  Output: a pointer to the initialized ubi_btNode structure (ie. the
+   *          same as the input pointer).
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  NodePtr->Link[ LEFT ]   = NULL;
+  NodePtr->Link[ PARENT ] = NULL;
+  NodePtr->Link[ RIGHT ]  = NULL;
+  NodePtr->gender         = EQUAL;
+  return( NodePtr );
+  } /* ubi_btInitNode */
+
+ubi_btRootPtr ubi_btInitTree( ubi_btRootPtr   RootPtr,
+                              ubi_btCompFunc  CompFunc,
+                              unsigned char   Flags )
+  /* ------------------------------------------------------------------------ **
+   * Initialize the fields of a Tree Root header structure.
+   *
+   *  Input:   RootPtr   - a pointer to an ubi_btRoot structure to be
+   *                       initialized.
+   *           CompFunc  - a pointer to a comparison function that will be used
+   *                       whenever nodes in the tree must be compared against
+   *                       outside values.
+   *           Flags     - One bytes worth of flags.  Flags include
+   *                       ubi_trOVERWRITE and ubi_trDUPKEY.  See the header
+   *                       file for more info.
+   *
+   *  Output:  a pointer to the initialized ubi_btRoot structure (ie. the
+   *           same value as RootPtr).
+   *
+   *  Note:    The interface to this function has changed from that of
+   *           previous versions.  The <Flags> parameter replaces two
+   *           boolean parameters that had the same basic effect.
+   *
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  if( RootPtr )
+    {
+    RootPtr->root   = NULL;
+    RootPtr->count  = 0L;
+    RootPtr->cmp    = CompFunc;
+    RootPtr->flags  = (Flags & ubi_trDUPKEY) ? ubi_trDUPKEY : Flags;
+    }                 /* There are only two supported flags, and they are
+                       * mutually exclusive.  ubi_trDUPKEY takes precedence
+                       * over ubi_trOVERWRITE.
+                       */
+  return( RootPtr );
+  } /* ubi_btInitTree */
+
+ubi_trBool ubi_btInsert( 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,
+                parent = NULL;
+  char          tmp;
+
+  if( !(OldNode) )       /* If they didn't give us a pointer, supply our own. */
+    OldNode = &OtherP;
+
+  (void)ubi_btInitNode( NewNode );     /* Init the new node's BinTree fields. */
+
+  /* Find a place for the new node. */
+  *OldNode = TreeFind(ItemPtr, (RootPtr->root), &parent, &tmp, (RootPtr->cmp));
+
+  /* Now add the node to the tree... */
+  if (!(*OldNode)) /* The easy one: we have a space for a new node! */
+    {
+    if (!(parent))
+      RootPtr->root = NewNode;
+    else
+      {
+      parent->Link[tmp]     = NewNode;
+      NewNode->Link[PARENT] = parent;
+      NewNode->gender       = tmp;
+      }
+    (RootPtr->count)++;
+    return( ubi_trTRUE );
+    }
+
+  /* If we reach this point, we know that a duplicate node exists.  This
+   * section adds the node to the tree if duplicate keys are allowed.
+   */
+  if( Dups_OK(RootPtr) )    /* Key exists, add duplicate */
+    {
+    ubi_btNodePtr q;
+
+    tmp = RIGHT;
+    q = (*OldNode);
+    *OldNode = NULL;
+    while( q )
+      {
+      parent = q;
+      if( tmp == EQUAL ) tmp = RIGHT;
+      q = q->Link[tmp];
+      if ( q )
+        tmp = AbNormal( (*(RootPtr->cmp))(ItemPtr, q) );
+      }
+    parent->Link[tmp]      = NewNode;
+    NewNode->Link[PARENT]  = parent;
+    NewNode->gender        = tmp;
+    (RootPtr->count)++;
+    return( ubi_trTRUE );
+    }
+
+  /* If we get to *this* point, we know that we are not allowed to have
+   * duplicate nodes, but our node keys match, so... may we replace the
+   * old one?
+   */
+  if( Ovwt_OK(RootPtr) )    /* Key exists, we replace */
+    {
+    if (!(parent))
+      ReplaceNode( &(RootPtr->root), *OldNode, NewNode );
+    else
+      ReplaceNode( &(parent->Link[(*OldNode)->gender]), *OldNode, NewNode );
+    return( ubi_trTRUE );
+    }
+
+  return( ubi_trFALSE );      /* Failure: could not replace an existing node. */
+  } /* ubi_btInsert */
+
+ubi_btNodePtr ubi_btRemove( 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 p,
+               *parentp;
+  char          tmp;
+
+  /* if the node has both left and right subtrees, then we have to swap
+   * it with another node.  The other node we choose will be the Prev()ious
+   * node, which is garunteed to have no RIGHT child.
+   */
+  if( (DeadNode->Link[LEFT]) && (DeadNode->Link[RIGHT]) )
+    SwapNodes( RootPtr, DeadNode, ubi_btPrev( 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 = &((DeadNode->Link[PARENT])->Link[DeadNode->gender]);
+  else
+    parentp = &( RootPtr->root );
+
+  /* Now link the parent to the only grand-child and patch up the gender. */
+  tmp = ((DeadNode->Link[LEFT])?LEFT:RIGHT);
+
+  p = (DeadNode->Link[tmp]);
+  if( p )
+    {
+    p->Link[PARENT] = DeadNode->Link[PARENT];
+    p->gender       = DeadNode->gender;
+    }
+  (*parentp) = p;
+
+  /* Finished, reduce the node count and return. */
+  (RootPtr->count)--;
+  return( DeadNode );
+  } /* ubi_btRemove */
+
+ubi_btNodePtr ubi_btLocate( 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().
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  register ubi_btNodePtr p;
+  ubi_btNodePtr   parent;
+  char            whichkid;
+
+  /* Start by searching for a matching node. */
+  p = TreeFind( FindMe,
+                RootPtr->root,
+                &parent,
+                &whichkid,
+                RootPtr->cmp );
+
+  if( p )   /* If we have found a match, we can resolve as follows: */
+    {
+    switch( CompOp )
+      {
+      case ubi_trLT:            /* It's just a jump to the left...  */
+        p = Border( RootPtr, FindMe, p, LEFT );
+        return( Neighbor( p, LEFT ) );
+      case ubi_trGT:            /* ...and then a jump to the right. */
+        p = Border( RootPtr, FindMe, p, RIGHT );
+        return( Neighbor( p, RIGHT ) );
+      }
+    p = Border( RootPtr, FindMe, p, LEFT );
+    return( p );
+    }
+
+  /* Else, no match. */
+  if( ubi_trEQ == CompOp )    /* If we were looking for an exact match... */
+    return( NULL );           /* ...forget it.                            */
+
+  /* We can still return a valid result for GT, GE, LE, and LT.
+   * <parent> points to a node with a value that is either just before or
+   * just after the target value.
+   * Remaining possibilities are LT and GT (including LE & GE).
+   */
+  if( (ubi_trLT == CompOp) || (ubi_trLE == CompOp) )
+    return( (LEFT  == whichkid) ? Neighbor( parent, whichkid ) : parent );
+  else
+    return( (RIGHT == whichkid) ? Neighbor( parent, whichkid ) : parent );
+  } /* ubi_btLocate */
+
+ubi_btNodePtr ubi_btFind( 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_btLocate().
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  return( qFind( RootPtr->cmp, FindMe, RootPtr->root ) );
+  } /* ubi_btFind */
+
+ubi_btNodePtr ubi_btNext( ubi_btNodePtr P )
+  /* ------------------------------------------------------------------------ **
+   * Given the node indicated by P, find the (sorted order) Next node in the
+   * tree.
+   *  Input:   P  -  a pointer to a node that exists in a binary tree.
+   *  Output:  A pointer to the "next" node in the tree, or NULL if P pointed
+   *           to the "last" node in the tree or was NULL.
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  return( Neighbor( P, RIGHT ) );
+  } /* ubi_btNext */
+
+ubi_btNodePtr ubi_btPrev( ubi_btNodePtr P )
+  /* ------------------------------------------------------------------------ **
+   * Given the node indicated by P, find the (sorted order) Previous node in
+   * the tree.
+   *  Input:   P  -  a pointer to a node that exists in a binary tree.
+   *  Output:  A pointer to the "previous" node in the tree, or NULL if P
+   *           pointed to the "first" node in the tree or was NULL.
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  return( Neighbor( P, LEFT ) );
+  } /* ubi_btPrev */
+
+ubi_btNodePtr ubi_btFirst( ubi_btNodePtr P )
+  /* ------------------------------------------------------------------------ **
+   * Given the node indicated by P, find the (sorted order) First node in the
+   * subtree of which *P is the root.
+   *  Input:   P  -  a pointer to a node that exists in a binary tree.
+   *  Output:  A pointer to the "first" node in a subtree that has *P as its
+   *           root.  This function will return NULL only if P is NULL.
+   *  Note:    In general, you will be passing in the value of the root field
+   *           of an ubi_btRoot structure.
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  return( SubSlide( P, LEFT ) );
+  } /* ubi_btFirst */
+
+ubi_btNodePtr ubi_btLast( ubi_btNodePtr P )
+  /* ------------------------------------------------------------------------ **
+   * Given the node indicated by P, find the (sorted order) Last node in the
+   * subtree of which *P is the root.
+   *  Input:   P  -  a pointer to a node that exists in a binary tree.
+   *  Output:  A pointer to the "last" node in a subtree that has *P as its
+   *           root.  This function will return NULL only if P is NULL.
+   *  Note:    In general, you will be passing in the value of the root field
+   *           of an ubi_btRoot structure.
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  return( SubSlide( P, RIGHT ) );
+  } /* ubi_btLast */
+
+ubi_btNodePtr ubi_btFirstOf( ubi_btRootPtr RootPtr,
+                             ubi_btItemPtr MatchMe,
+                             ubi_btNodePtr p )
+  /* ------------------------------------------------------------------------ **
+   * Given a tree that a allows duplicate keys, and a pointer to a node in
+   * the tree, this function will return a pointer to the first (traversal
+   * order) node with the same key value.
+   *
+   *  Input:  RootPtr - A pointer to the root of the tree.
+   *          MatchMe - A pointer to the key value.  This should probably
+   *                    point to the key within node *p.
+   *          p       - A pointer to a node in the tree.
+   *  Output: A pointer to the first node in the set of nodes with keys
+   *          matching <FindMe>.
+   *  Notes:  Node *p MUST be in the set of nodes with keys matching
+   *          <FindMe>.  If not, this function will return NULL.
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  /* If our starting point is invalid, return NULL. */
+  if( !p || AbNormal( (*(RootPtr->cmp))( MatchMe, p ) != EQUAL ) )
+    return( NULL );
+  return( Border( RootPtr, MatchMe, p, LEFT ) );
+  } /* ubi_btFirstOf */
+
+ubi_btNodePtr ubi_btLastOf( ubi_btRootPtr RootPtr,
+                            ubi_btItemPtr MatchMe,
+                            ubi_btNodePtr p )
+  /* ------------------------------------------------------------------------ **
+   * Given a tree that a allows duplicate keys, and a pointer to a node in
+   * the tree, this function will return a pointer to the last (traversal
+   * order) node with the same key value.
+   *
+   *  Input:  RootPtr - A pointer to the root of the tree.
+   *          MatchMe - A pointer to the key value.  This should probably
+   *                    point to the key within node *p.
+   *          p       - A pointer to a node in the tree.
+   *  Output: A pointer to the last node in the set of nodes with keys
+   *          matching <FindMe>.
+   *  Notes:  Node *p MUST be in the set of nodes with keys matching
+   *          <FindMe>.  If not, this function will return NULL.
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  /* If our starting point is invalid, return NULL. */
+  if( !p || AbNormal( (*(RootPtr->cmp))( MatchMe, p ) != EQUAL ) )
+    return( NULL );
+  return( Border( RootPtr, MatchMe, p, RIGHT ) );
+  } /* ubi_btLastOf */
+
+ubi_trBool ubi_btTraverse( ubi_btRootPtr   RootPtr,
+                           ubi_btActionRtn EachNode,
+                           void           *UserData )
+  /* ------------------------------------------------------------------------ **
+   * Traverse a tree in sorted order (non-recursively).  At each node, call
+   * (*EachNode)(), passing a pointer to the current node, and UserData as the
+   * second parameter.
+   *  Input:   RootPtr  -  a pointer to an ubi_btRoot structure that indicates
+   *                       the tree to be traversed.
+   *           EachNode -  a pointer to a function to be called at each node
+   *                       as the node is visited.
+   *           UserData -  a generic pointer that may point to anything that
+   *                       you choose.
+   *  Output:  A boolean value.  FALSE if the tree is empty, otherwise TRUE.
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  ubi_btNodePtr p;
+
+  if( !(p = ubi_btFirst( RootPtr->root )) ) return( ubi_trFALSE );
+
+  while( p )
+    {
+    EachNode( p, UserData );
+    p = ubi_btNext( p );
+    }
+  return( ubi_trTRUE );
+  } /* ubi_btTraverse */
+
+ubi_trBool ubi_btKillTree( ubi_btRootPtr     RootPtr,
+                           ubi_btKillNodeRtn FreeNode )
+  /* ------------------------------------------------------------------------ **
+   * Delete an entire tree (non-recursively) and reinitialize the ubi_btRoot
+   * structure.  Note that this function will return FALSE if either parameter
+   * is NULL.
+   *
+   *  Input:   RootPtr  -  a pointer to an ubi_btRoot structure that indicates
+   *                       the root of the tree to delete.
+   *           FreeNode -  a function that will be called for each node in the
+   *                       tree to deallocate the memory used by the node.
+   *
+   *  Output:  A boolean value.  FALSE if either input parameter was NULL, else
+   *           TRUE.
+   *
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  ubi_btNodePtr p, q;
+
+  if( !(RootPtr) || !(FreeNode) )
+    return( ubi_trFALSE );
+
+  p = ubi_btFirst( RootPtr->root );
+  while( p )
+    {
+    q = p;
+    while( q->Link[RIGHT] )
+      q = SubSlide( q->Link[RIGHT], LEFT );
+    p = q->Link[PARENT];
+    if( p )
+      p->Link[ ((p->Link[LEFT] == q)?LEFT:RIGHT) ] = NULL;
+    FreeNode((void *)q);
+    }
+
+  (void)ubi_btInitTree( RootPtr,
+                        RootPtr->cmp,
+                        RootPtr->flags );
+  return( ubi_trTRUE );
+  } /* ubi_btKillTree */
+
+ubi_btNodePtr ubi_btLeafNode( ubi_btNodePtr leader )
+  /* ------------------------------------------------------------------------ **
+   * Returns a pointer to a leaf node.
+   *
+   *  Input:  leader  - Pointer to a node at which to start the descent.
+   *
+   *  Output: A pointer to a leaf node selected in a somewhat arbitrary
+   *          manner.
+   *
+   *  Notes:  I wrote this function because I was using splay trees as a
+   *          database cache.  The cache had a maximum size on it, and I
+   *          needed a way of choosing a node to sacrifice if the cache
+   *          became full.  In a splay tree, less recently accessed nodes
+   *          tend toward the bottom of the tree, meaning that leaf nodes
+   *          are good candidates for removal.  (I really can't think of
+   *          any other reason to use this function.)
+   *        + In a simple binary tree or an AVL tree, the most recently
+   *          added nodes tend to be nearer the bottom, making this a *bad*
+   *          way to choose which node to remove from the cache.
+   *        + Randomizing the traversal order is probably a good idea.  You
+   *          can improve the randomization of leaf node selection by passing
+   *          in pointers to nodes other than the root node each time.  A
+   *          pointer to any node in the tree will do.  Of course, if you
+   *          pass a pointer to a leaf node you'll get the same thing back.
+   *
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  ubi_btNodePtr follower = NULL;
+  int           whichway = LEFT;
+
+  while( NULL != leader )
+    {
+    follower = leader;
+    leader   = follower->Link[ whichway ];
+    if( NULL == leader )
+      {
+      whichway = RevWay( whichway );
+      leader   = follower->Link[ whichway ];
+      }
+    }
+
+  return( follower );
+  } /* ubi_btLeafNode */
+
+int ubi_btModuleID( 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 )
+      list[1] = NULL;
+    return( 1 );
+    }
+  return( 0 );
+  } /* ubi_btModuleID */
+
+
+/* ========================================================================== */