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  • Committer: Lee Bieber
  • Date: 2011-04-14 16:20:43 UTC
  • mfrom: (2277.1.3 build)
  • Revision ID: kalebral@gmail.com-20110414162043-2khq8mql7gvodnzn
Merge Olaf - Refactor Session Cache and Remove table::Cache::singleton()
Merge Olaf - Refactor Thread
Merge Olaf - remove unused functions

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Lines of Context:
drizzled/tree.cc
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static void right_rotate(TREE_ELEMENT **parent, TREE_ELEMENT *leaf);
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static void rb_insert(TREE *tree,TREE_ELEMENT ***parent,
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                      TREE_ELEMENT *leaf);
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static void rb_delete_fixup(TREE *tree,TREE_ELEMENT ***parent);
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void init_tree(TREE *tree, size_t default_alloc_size, uint32_t memory_limit,
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  return element;
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}
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int tree_delete(TREE *tree, void *key, uint32_t key_size, void *custom_arg)
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{
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  int remove_colour;
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  TREE_ELEMENT *element,***parent, ***org_parent, *nod;
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  if (!tree->with_delete)
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    return 1;                                   /* not allowed */
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  parent= tree->parents;
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  *parent= &tree->root; element= tree->root;
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  for (;;)
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  {
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    int cmp;
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    if (element == &tree->null_element)
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      return 1;                         /* Was not in tree */
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    if ((cmp = (*tree->compare)(custom_arg, ELEMENT_KEY(tree,element),
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                                key)) == 0)
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      break;
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    if (cmp < 0)
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    {
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      *++parent= &element->right; element= element->right;
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    }
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    else
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    {
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      *++parent = &element->left; element= element->left;
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    }
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  }
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  if (element->left == &tree->null_element)
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  {
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    (**parent)= element->right;
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    remove_colour= element->colour;
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  }
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  else if (element->right == &tree->null_element)
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  {
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    (**parent)= element->left;
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    remove_colour= element->colour;
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  }
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  else
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  {
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    org_parent= parent;
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    *++parent= &element->right; nod= element->right;
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    while (nod->left != &tree->null_element)
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    {
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      *++parent= &nod->left; nod= nod->left;
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    }
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    (**parent)= nod->right;             /* unlink nod from tree */
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    remove_colour= nod->colour;
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    org_parent[0][0]= nod;              /* put y in place of element */
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    org_parent[1]= &nod->right;
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    nod->left= element->left;
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    nod->right= element->right;
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    nod->colour= element->colour;
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  }
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  if (remove_colour == BLACK)
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    rb_delete_fixup(tree,parent);
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  if (tree->free)
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    (*tree->free)(ELEMENT_KEY(tree,element), free_free, tree->custom_arg);
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  tree->allocated-= sizeof(TREE_ELEMENT) + tree->size_of_element + key_size;
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  free((unsigned char*) element);
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  tree->elements_in_tree--;
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  return 0;
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}
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void *tree_search_key(TREE *tree, const void *key,
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                      TREE_ELEMENT **parents, TREE_ELEMENT ***last_pos,
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                      enum ha_rkey_function flag, void *custom_arg)
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  return *last_pos ? ELEMENT_KEY(tree, **last_pos) : NULL;
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}
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/*
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  Search first (the most left) or last (the most right) tree element
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*/
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void *tree_search_edge(TREE *tree, TREE_ELEMENT **parents,
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                       TREE_ELEMENT ***last_pos, int child_offs)
411
 
{
412
 
  TREE_ELEMENT *element= tree->root;
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414
 
  *parents= &tree->null_element;
415
 
  while (element != &tree->null_element)
416
 
  {
417
 
    *++parents= element;
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    element= ELEMENT_CHILD(element, child_offs);
419
 
  }
420
 
  *last_pos= parents;
421
 
  return **last_pos != &tree->null_element ?
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    ELEMENT_KEY(tree, **last_pos) : NULL;
423
 
}
424
 
 
425
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void *tree_search_next(TREE *tree, TREE_ELEMENT ***last_pos, int l_offs,
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                       int r_offs)
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{
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  tree->root->colour=BLACK;
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}
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static void rb_delete_fixup(TREE *tree, TREE_ELEMENT ***parent)
635
 
{
636
 
  TREE_ELEMENT *x,*w,*par;
637
 
 
638
 
  x= **parent;
639
 
  while (x != tree->root && x->colour == BLACK)
640
 
  {
641
 
    if (x == (par=parent[-1][0])->left)
642
 
    {
643
 
      w= par->right;
644
 
      if (w->colour == RED)
645
 
      {
646
 
        w->colour= BLACK;
647
 
        par->colour= RED;
648
 
        left_rotate(parent[-1],par);
649
 
        parent[0]= &w->left;
650
 
        *++parent= &par->left;
651
 
        w= par->right;
652
 
      }
653
 
      if (w->left->colour == BLACK && w->right->colour == BLACK)
654
 
      {
655
 
        w->colour= RED;
656
 
        x= par;
657
 
        parent--;
658
 
      }
659
 
      else
660
 
      {
661
 
        if (w->right->colour == BLACK)
662
 
        {
663
 
          w->left->colour= BLACK;
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          w->colour= RED;
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          right_rotate(&par->right,w);
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          w= par->right;
667
 
        }
668
 
        w->colour= par->colour;
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        par->colour= BLACK;
670
 
        w->right->colour= BLACK;
671
 
        left_rotate(parent[-1],par);
672
 
        x= tree->root;
673
 
        break;
674
 
      }
675
 
    }
676
 
    else
677
 
    {
678
 
      w=par->left;
679
 
      if (w->colour == RED)
680
 
      {
681
 
        w->colour= BLACK;
682
 
        par->colour= RED;
683
 
        right_rotate(parent[-1],par);
684
 
        parent[0]= &w->right;
685
 
        *++parent= &par->right;
686
 
        w= par->left;
687
 
      }
688
 
      if (w->right->colour == BLACK && w->left->colour == BLACK)
689
 
      {
690
 
        w->colour= RED;
691
 
        x= par;
692
 
        parent--;
693
 
      }
694
 
      else
695
 
      {
696
 
        if (w->left->colour == BLACK)
697
 
        {
698
 
          w->right->colour= BLACK;
699
 
          w->colour= RED;
700
 
          left_rotate(&par->left,w);
701
 
          w= par->left;
702
 
        }
703
 
        w->colour= par->colour;
704
 
        par->colour= BLACK;
705
 
        w->left->colour= BLACK;
706
 
        right_rotate(parent[-1],par);
707
 
        x= tree->root;
708
 
        break;
709
 
      }
710
 
    }
711
 
  }
712
 
  x->colour= BLACK;
713
 
}
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715
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} /* namespace drizzled */