Testing PRB Trees - GNU libavl 2.0.2
Author: Ben Pfaff

15.5 Testing |

No comment is necessary.

    583. <prb-test.c 583> =
    <License 1>
    #include <assert.h>
    #include <limits.h>
    #include <stdio.h>
    #include "prb.h"
    #include "test.h"

    <BST print function; bst => prb 119>
    <BST traverser check function; bst => prb 104>
    <Compare two PRB trees for structure and content 584>
    <Recursively verify PRB tree structure 585>
    <RB tree verify function; rb => prb 244>
    <BST test function; bst => prb 100>
    <BST overflow test function; bst => prb 122>

    584. <Compare two PRB trees for structure and content 584> =
    static int
    compare_trees (struct prb_node *a, struct prb_node *b)
    {
      int okay;

      if (a == NULL || b == NULL)
        {
          assert (a == NULL && b == NULL);
          return 1;
        }

      if (*(int *) a->prb_data != *(int *) b->prb_data
          || ((a->prb_link[0] != NULL) != (b->prb_link[0] != NULL))
          || ((a->prb_link[1] != NULL) != (b->prb_link[1] != NULL))
          || a->prb_color != b->prb_color)
        {
          printf (" Copied nodes differ: a=%d%c b=%d%c a:",
                  *(int *) a->prb_data, a->prb_color == PRB_RED ? 'r' : 'b',
                  *(int *) b->prb_data, b->prb_color == PRB_RED ? 'r' : 'b');

          if (a->prb_link[0] != NULL)
            printf ("l");
          if (a->prb_link[1] != NULL)
            printf ("r");

          printf (" b:");
          if (b->prb_link[0] != NULL)
            printf ("l");
          if (b->prb_link[1] != NULL)
            printf ("r");

          printf ("\n");
          return 0;
        }

      okay = 1;
      if (a->prb_link[0] != NULL)
        okay &= compare_trees (a->prb_link[0], b->prb_link[0]);
      if (a->prb_link[1] != NULL)
        okay &= compare_trees (a->prb_link[1], b->prb_link[1]);
      return okay;
    }

This code is included in 583.

    585. <Recursively verify PRB tree structure 585> =
    /* Examines the binary tree rooted at node.
       Zeroes *okay if an error occurs.
       Otherwise, does not modify *okay.
       Sets *count to the number of nodes in that tree,
       including node itself if node != NULL.
       Sets *bh to the tree's black-height.
       All the nodes in the tree are verified to be at least min
       but no greater than max. */
    static void
    recurse_verify_tree (struct prb_node *node, int *okay, size_t *count,
                         int min, int max, int *bh)
    {
      int d;                /* Value of this node's data. */
      size_t subcount[2];   /* Number of nodes in subtrees. */
      int subbh[2];         /* Black-heights of subtrees. */
      int i;

      if (node == NULL)
        {
          *count = 0;
          *bh = 0;
          return;
        }
      d = *(int *) node->prb_data;

      <Verify binary search tree ordering 114>

      recurse_verify_tree (node->prb_link[0], okay, &subcount[0],
                           min, d - 1, &subbh[0]);
      recurse_verify_tree (node->prb_link[1], okay, &subcount[1],
                           d + 1, max, &subbh[1]);
      *count = 1 + subcount[0] + subcount[1];
      *bh = (node->prb_color == PRB_BLACK) + subbh[0];

      <Verify RB node color; rb => prb 241>
      <Verify RB node rule 1 compliance; rb => prb 242>
      <Verify RB node rule 2 compliance; rb => prb 243>

      <Verify PBST node parent pointers; pbst => prb 518>
    }

This code is included in 583.

15.4.4 Symmetric Case | 15 Red-Black Trees with Parent Pointers | Appendix A References