Ejemplo n.º 1
0
static Compare SplayFindLastCompare(Tree node, TreeKey key)
{
  SplayFindClosure my;
  SplayTestNodeFunction testNode;
  SplayTestTreeFunction testTree;
  void *testClosure;
  SplayTree splay;

  AVERT_CRITICAL(Tree, node);
  AVER_CRITICAL(key != NULL);

  /* Lift closure values into variables so that they aren't aliased by
     calls to the test functions. */
  my = (SplayFindClosure)key;
  testClosure = my->testClosure;
  testNode = my->testNode;
  testTree = my->testTree;
  splay = my->splay;

  if (TreeHasRight(node) &&
      (*testTree)(splay, TreeRight(node), testClosure)) {
    return CompareGREATER;
  } else if ((*testNode)(splay, node, testClosure)) {
    my->found = TRUE;
    return CompareEQUAL;
  } else {
    /* See SplayFindFirstCompare. */
    if (TreeHasLeft(node) &&
        !(*testTree)(splay, TreeLeft(node), testClosure)) {
      my->found = FALSE;
      return CompareEQUAL;
    }
    return CompareLESS;
  }
}
Ejemplo n.º 2
0
void SplayNodeInit(SplayTree splay, Tree node)
{
  AVERT(SplayTree, splay);
  AVERT(Tree, node);
  AVER(!TreeHasLeft(node)); /* otherwise, call SplayNodeRefresh */
  AVER(!TreeHasRight(node)); /* otherwise, call SplayNodeRefresh */

  splay->updateNode(splay, node);
}
Ejemplo n.º 3
0
Bool TreeTraverse(Tree tree,
                  TreeCompare compare,
                  TreeKeyMethod key,
                  TreeVisitor visit, void *closureP, Size closureS)
{
  Tree parent, node;
  
  AVERT(Tree, tree);
  AVER(FUNCHECK(visit));
  /* closureP, closureS arbitrary */

  parent = TreeEMPTY;
  node = tree;
  
  if (node == TreeEMPTY)
    return TRUE;

down:
  if (TreeHasLeft(node)) {
    node = stepDownLeft(node, &parent);
    AVER(compare(parent, key(node)) == CompareLESS);
    goto down;
  }
  if (!visit(node, closureP, closureS))
    goto abort;
  if (TreeHasRight(node)) {
    node = stepDownRight(node, &parent);
    AVER(compare(parent, key(node)) != CompareLESS);
    goto down;
  }

up:
  if (parent == TreeEMPTY)
    return TRUE;
  if (compare(parent, key(node)) != CompareLESS) {
    node = stepUpLeft(node, &parent);
    goto up;
  }
  node = stepUpRight(node, &parent);
  if (!visit(node, closureP, closureS))
    goto abort;
  if (!TreeHasRight(node))
    goto up;
  node = stepDownRight(node, &parent);
  goto down;

abort:
  if (parent == TreeEMPTY)
    return FALSE;
  if (compare(parent, key(node)) != CompareLESS)
    node = stepUpLeft(node, &parent);
  else
    node = stepUpRight(node, &parent);
  goto abort;
}
Ejemplo n.º 4
0
Bool SplayTreeNeighbours(Tree *leftReturn, Tree *rightReturn,
                         SplayTree splay, TreeKey key)
{
  SplayStateStruct stateStruct;
  Bool found;
  Compare cmp;
#ifdef SPLAY_DEBUG
  Count count = SplayDebugCount(splay);
#endif


  AVERT(SplayTree, splay);
  AVER(leftReturn != NULL);
  AVER(rightReturn != NULL);

  if (SplayTreeIsEmpty(splay)) {
    *leftReturn = *rightReturn = TreeEMPTY;
    return TRUE;
  }

  cmp = SplaySplit(&stateStruct, splay, key, splay->compare);

  switch (cmp) {
  default:
    NOTREACHED;
    /* defensive fall-through */
  case CompareEQUAL:
    found = FALSE;
    break;

  case CompareLESS:
    AVER(!TreeHasLeft(stateStruct.middle));
    *rightReturn = stateStruct.middle;
    *leftReturn = stateStruct.leftLast;
    found = TRUE;
    break;

  case CompareGREATER:
    AVER(!TreeHasRight(stateStruct.middle));
    *leftReturn = stateStruct.middle;
    *rightReturn = stateStruct.rightFirst;
    found = TRUE;
    break;
  }

  SplayAssemble(splay, &stateStruct);
  SplayTreeSetRoot(splay, stateStruct.middle);

#ifdef SPLAY_DEBUG
  AVER(count == SplayDebugCount(splay));
#endif

  return found;
}
Ejemplo n.º 5
0
Count TreeToVine(Tree *link)
{
  Count count = 0;
  
  AVER(link != NULL);
  AVERT(Tree, *link);

  while (*link != TreeEMPTY) {
    while (TreeHasLeft(*link))
      TreeRotateRight(link);
    link = &((*link)->right);
    ++count;
  }
  
  return count;
}
Ejemplo n.º 6
0
static Res SplayNodeDescribe(Tree node, mps_lib_FILE *stream,
                             TreeDescribeFunction nodeDescribe)
{
  Res res;

  if (!TreeCheck(node))
    return ResFAIL;
  if (stream == NULL)
    return ResFAIL;
  if (nodeDescribe == NULL)
    return ResFAIL;

  res = WriteF(stream, 0, "( ", NULL);
  if (res != ResOK)
    return res;

  if (TreeHasLeft(node)) {
    res = SplayNodeDescribe(TreeLeft(node), stream, nodeDescribe);
    if (res != ResOK)
      return res;

    res = WriteF(stream, 0, " / ", NULL);
    if (res != ResOK)
      return res;
  }

  res = (*nodeDescribe)(node, stream);
  if (res != ResOK)
    return res;

  if (TreeHasRight(node)) {
    res = WriteF(stream, 0, " \\ ", NULL);
    if (res != ResOK)
      return res;

    res = SplayNodeDescribe(TreeRight(node), stream, nodeDescribe);
    if (res != ResOK)
      return res;
  }

  res = WriteF(stream, 0, " )", NULL);
  if (res != ResOK)
    return res;

  return ResOK;
}
Ejemplo n.º 7
0
static Compare SplayFindFirstCompare(Tree node, TreeKey key)
{
  SplayFindClosure closure;
  void *closureP;
  Size closureS;
  SplayTestNodeFunction testNode;
  SplayTestTreeFunction testTree;
  SplayTree splay;

  AVERT(Tree, node);
  AVER(key != NULL);

  /* Lift closure values into variables so that they aren't aliased by
     calls to the test functions. */
  closure = (SplayFindClosure)key;
  closureP = closure->p;
  closureS = closure->s;
  testNode = closure->testNode;
  testTree = closure->testTree;
  splay = closure->splay;
  
  if (TreeHasLeft(node) &&
     (*testTree)(splay, TreeLeft(node), closureP, closureS)) {
    return CompareLESS;
  } else if ((*testNode)(splay, node, closureP, closureS)) {
    closure->found = TRUE;
    return CompareEQUAL;
  } else {
    /* If there's a right subtree but it doesn't satisfy the tree test
       then we want to terminate the splay right now.  SplaySplay will
       return TRUE, so the caller must check closure->found to find out
       whether the result node actually satisfies testNode. */
    if (TreeHasRight(node) &&
        !(*testTree)(splay, TreeRight(node), closureP, closureS)) {
      closure->found = FALSE;
      return CompareEQUAL;
    }
    return CompareGREATER;
  }
}
Ejemplo n.º 8
0
Bool SplayTreeDelete(SplayTree splay, Tree node)
{
  Tree leftLast;
  Compare cmp;

  AVERT(SplayTree, splay);
  AVERT(Tree, node);

  if (SplayTreeIsEmpty(splay))
    return FALSE;

  cmp = SplaySplay(splay, splay->nodeKey(node), splay->compare);
  AVER(cmp != CompareEQUAL || SplayTreeRoot(splay) == node);

  if (cmp != CompareEQUAL) {
    return FALSE;
  } else if (!TreeHasLeft(node)) {
    SplayTreeSetRoot(splay, TreeRight(node));
    TreeClearRight(node);
  } else if (!TreeHasRight(node)) {
    SplayTreeSetRoot(splay, TreeLeft(node));
    TreeClearLeft(node);
  } else {
    Tree rightHalf = TreeRight(node);
    TreeClearRight(node);
    SplayTreeSetRoot(splay, TreeLeft(node));
    TreeClearLeft(node);
    (void)SplaySplay(splay, NULL, compareGreater);
    leftLast = SplayTreeRoot(splay);
    AVER(leftLast != TreeEMPTY);
    AVER(!TreeHasRight(leftLast));
    TreeSetRight(leftLast, rightHalf);
    splay->updateNode(splay, leftLast);
  }

  TreeFinish(node);

  return TRUE;
}
Ejemplo n.º 9
0
static Compare SplayFindLastCompare(Tree node, TreeKey key)
{
  SplayFindClosure closure;
  void *closureP;
  Size closureS;
  SplayTestNodeFunction testNode;
  SplayTestTreeFunction testTree;
  SplayTree splay;

  AVERT(Tree, node);
  AVER(key != NULL);

  /* Lift closure values into variables so that they aren't aliased by
     calls to the test functions. */
  closure = (SplayFindClosure)key;
  closureP = closure->p;
  closureS = closure->s;
  testNode = closure->testNode;
  testTree = closure->testTree;
  splay = closure->splay;

  if (TreeHasRight(node) &&
     (*testTree)(splay, TreeRight(node), closureP, closureS)) {
     return CompareGREATER;
  } else if ((*testNode)(splay, node, closureP, closureS)) {
    closure->found = TRUE;
    return CompareEQUAL;
  } else {
    /* See SplayFindFirstCompare. */
    if (TreeHasLeft(node) &&
        !(*testTree)(splay, TreeLeft(node), closureP, closureS)) {
      closure->found = FALSE;
      return CompareEQUAL;
    }
    return CompareLESS;
  }
}
Ejemplo n.º 10
0
static Compare SplaySplitRev(SplayStateStruct *stateReturn,
                             SplayTree splay, TreeKey key,
                             TreeCompareFunction compare)
{
  Tree middle, leftLast, rightFirst;
  Compare cmp;

  AVERT(SplayTree, splay);
  AVER(FUNCHECK(compare));
  AVER(!SplayTreeIsEmpty(splay));
  
  leftLast = TreeEMPTY;
  rightFirst = TreeEMPTY;
  middle = SplayTreeRoot(splay);
  for (;;) {
    cmp = compare(middle, key);
    switch(cmp) {
    default:
      NOTREACHED;
      /* defensive fall-through */
    case CompareEQUAL:
      goto stop;

    case CompareLESS:
      if (!TreeHasLeft(middle))
        goto stop;
      middle = SplayZigRev(middle, &rightFirst);
      cmp = compare(middle, key);
      switch(cmp) {
      default:
        NOTREACHED;
        /* defensive fall-through */
      case CompareEQUAL:
        goto stop;
      case CompareLESS:
        if (!TreeHasLeft(middle))
          goto stop;
        middle = SplayZigZigRev(middle, &rightFirst);
        splay->updateNode(splay, TreeRight(rightFirst));
        break;
      case CompareGREATER:
        if (!TreeHasRight(middle))
          goto stop;
        middle = SplayZagRev(middle, &leftLast);
        break;
      }
      break;

    case CompareGREATER:
      if (!TreeHasRight(middle))
        goto stop;
      middle = SplayZagRev(middle, &leftLast);
      cmp = compare(middle, key);
      switch(cmp) {
      default:
        NOTREACHED;
        /* defensive fall-through */
      case CompareEQUAL:
        goto stop;
      case CompareGREATER:
        if (!TreeHasRight(middle))
          goto stop;
        middle = SplayZagZagRev(middle, &leftLast);
        splay->updateNode(splay, TreeLeft(leftLast));
        break;
      case CompareLESS:
        if (!TreeHasLeft(middle))
          goto stop;
        middle = SplayZigRev(middle, &rightFirst);
        break;
      }
      break;
    }
  }

stop:
  stateReturn->middle = middle;
  stateReturn->leftLast = leftLast;
  stateReturn->rightFirst = rightFirst;
  return cmp;
}
Ejemplo n.º 11
0
static Compare SplaySplitDown(SplayStateStruct *stateReturn,
                              SplayTree splay, TreeKey key,
                              TreeCompareFunction compare)
{
  TreeStruct sentinel;
  Tree middle, leftLast, rightFirst, leftPrev, rightNext;
  Compare cmp;

  AVERT(SplayTree, splay);
  AVER(FUNCHECK(compare));
  AVER(!SplayTreeIsEmpty(splay));
  AVER(!SplayHasUpdate(splay));
  
  TreeInit(&sentinel);
  leftLast = &sentinel;
  rightFirst = &sentinel;
  middle = SplayTreeRoot(splay);
  for (;;) {
    cmp = compare(middle, key);
    switch(cmp) {
    default:
      NOTREACHED;
      /* defensive fall-through */
    case CompareEQUAL:
      goto stop;

    case CompareLESS:
      if (!TreeHasLeft(middle))
        goto stop;
      middle = SplayZig(middle, &rightFirst, &rightNext);
      cmp = compare(middle, key);
      switch(cmp) {
      default:
        NOTREACHED;
        /* defensive fall-through */
      case CompareEQUAL:
        goto stop;
      case CompareLESS:
        if (!TreeHasLeft(middle))
          goto stop;
        middle = SplayZigZig(middle, &rightFirst, rightNext);
        break;
      case CompareGREATER:
        if (!TreeHasRight(middle))
          goto stop;
        middle = SplayZag(middle, &leftLast, &leftPrev);
        break;
      }
      break;

    case CompareGREATER:
      if (!TreeHasRight(middle))
        goto stop;
      middle = SplayZag(middle, &leftLast, &leftPrev);
      cmp = compare(middle, key);
      switch(cmp) {
      default:
        NOTREACHED;
        /* defensive fall-through */
      case CompareEQUAL:
        goto stop;
      case CompareGREATER:
        if (!TreeHasRight(middle))
          goto stop;
        middle = SplayZagZag(middle, &leftLast, leftPrev);
        break;
      case CompareLESS:
        if (!TreeHasLeft(middle))
          goto stop;
        middle = SplayZig(middle, &rightFirst, &rightNext);
        break;
      }
      break;
    }
  }

stop:
  stateReturn->middle = middle;
  stateReturn->left = TreeRight(&sentinel);
  stateReturn->leftLast = leftLast == &sentinel ? TreeEMPTY : leftLast;
  stateReturn->right = TreeLeft(&sentinel);
  stateReturn->rightFirst = rightFirst == &sentinel ? TreeEMPTY : rightFirst;
  return cmp;
}