Backed out changes that attempted to address a pointer array using -1,0,1.

Jeremy pointed out that there might be problems with this.  Darn shame.
(This used to be commit ce9acc96a6cbc91f0a3f95221c3e8f801cbdb602)

1 files changed, 94 insertions, 24 deletions

diff --git a/source3/ubiqx/ubi_AVLtree.h b/source3/ubiqx/ubi_AVLtree.h
index c7cac0ed1e..ebae7f3c13 100644
--- a/source3/ubiqx/ubi_AVLtree.h
+++ b/source3/ubiqx/ubi_AVLtree.h
@@ -35,22 +35,89 @@
  *
  * -------------------------------------------------------------------------- **
  * Log: ubi_AVLtree.h,v
- * Revision 3.1  1997/12/18 06:27:01  crh
- * Fixed some comment bugs.
+ * 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 3.0  1997/12/08 05:39:01  crh
- * This is a new major revision level.  The handling of the pointers in the
- * ubi_trNode structure was redesigned.  The result is that there are fewer
- * macros floating about, and fewer cases in which values have to be
- * incremented or decremented.  See ubi_BinTree for more information.
+ * 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.
  *
- * Revision 2; 1995/03/05 - 1997/12/07:
- * An overhaul to the node delete process.  I had gotten it wrong in a
- * couple of places, thought I'd fixed it, and then found that I'd missed
- * something more.  Thanks to Andrew Leppard for the bug report!
+ * 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 1;  93/10/15 - 95/03/05:
- * Added the ubi_tr defines.  See ubi_BinTree.h for more info.
+ * 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_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).
  *
@@ -66,7 +133,6 @@
  *       header so that you can use the structure as a building block.
  *
  *  The fields are as follows:
- *    leftlink -  A space filler.  This field will be accessed as Link[-1].
  *    Link     -  An array of pointers.  These pointers are manipulated by the
  *                BT and AVL routines, and indicate the left and right child
  *                nodes, plus the parent node.  By keeping track of the parent
@@ -81,21 +147,25 @@
  *                indicates which subtree of the current node is longer, or if
  *                the subtrees are, in fact, balanced with respect to each
  *                other.
- *
+ *  ------------------------------------------------------------------------- **
  */
 
-typedef struct ubi_avlNodeStruct
-  {
-  struct ubi_avlNodeStruct *leftlink;
-  struct ubi_avlNodeStruct *Link[2];
-  signed char               gender; 
-  signed char               balance;
-  } ubi_avlNode;
+typedef struct ubi_avlNodeStruct {
+  struct ubi_avlNodeStruct
+         *Link[3];      /* Normal Binary Tree Node type.                      */
+  char    gender;       /* The node is either the RIGHT or LEFT child of its  */
+                        /* parent, or is the root node.                       */
+  char    balance;      /* In an AVL tree, each node is the root of a subtree */
+                        /* that may be balanced, or be one node longer to the */
+                        /* right or left.  This field keeps track of the      */
+                        /* balance value of each node.                        */
+    } ubi_avlNode;
 
-typedef ubi_avlNode *ubi_avlNodePtr;    /* a Pointer to an AVL node. */
+typedef ubi_avlNode *ubi_avlNodePtr;    /* a Pointer to an AVL node */
 
 /* -------------------------------------------------------------------------- **
- *  Function prototypes...
+ *  Function prototypes.
+ * -------------------------------------------------------------------------- **
  */
 
 ubi_avlNodePtr ubi_avlInitNode( ubi_avlNodePtr NodePtr );