path: root/ace/Timer_Heap_T.cpp

// $Id$

#if !defined (ACE_TIMER_HEAP_T_C)
#define ACE_TIMER_HEAP_T_C

#define ACE_BUILD_DLL

#include "ace/Timer_Heap_T.h"

ACE_RCSID(ace, Timer_Heap_T, "$Id$")

// Define some simple macros to clarify the code.
#define ACE_HEAP_PARENT(X) (X == 0 ? 0 : (((X) - 1) / 2))
#define ACE_HEAP_LCHILD(X) (((X)+(X))+1)


// Constructor that takes in an <ACE_Timer_Heap_T> to iterate over.

template <class TYPE, class FUNCTOR, class ACE_LOCK>
ACE_Timer_Heap_Iterator_T<TYPE, FUNCTOR, ACE_LOCK>::ACE_Timer_Heap_Iterator_T (ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK> &heap)
  : timer_heap_ (heap)
{
  ACE_TRACE ("ACE_Timer_Heap_Iterator::ACE_Timer_Heap_Iterator");
  this->first();
}

template <class TYPE, class FUNCTOR, class ACE_LOCK>
ACE_Timer_Heap_Iterator_T<TYPE, FUNCTOR, ACE_LOCK>::~ACE_Timer_Heap_Iterator_T (void)
{
}


// Positions the iterator at the first node in the heap array

template <class TYPE, class FUNCTOR, class ACE_LOCK> void
ACE_Timer_Heap_Iterator_T<TYPE, FUNCTOR, ACE_LOCK>::first (void)
{
  this->position_ = 0;
}


// Positions the iterator at the next node in the heap array

template <class TYPE, class FUNCTOR, class ACE_LOCK> void
ACE_Timer_Heap_Iterator_T<TYPE, FUNCTOR, ACE_LOCK>::next (void)
{
  if (this->position_ != this->timer_heap_.cur_size_)
    this->position_++;
}


// Returns true the <position_> is at the end of the heap array

template <class TYPE, class FUNCTOR, class ACE_LOCK> int
ACE_Timer_Heap_Iterator_T<TYPE, FUNCTOR, ACE_LOCK>::isdone (void)
{
  return this->position_ == this->timer_heap_.cur_size_;
}


// Returns the node at the current position in the heap or 0 if at the end

template <class TYPE, class FUNCTOR, class ACE_LOCK> ACE_Timer_Node_T<TYPE> *
ACE_Timer_Heap_Iterator_T<TYPE, FUNCTOR, ACE_LOCK>::item (void)
{
  if (this->position_ != this->timer_heap_.cur_size_)
    return this->timer_heap_.heap_[this->position_];
  return 0;
}

// Constructor

template <class TYPE, class FUNCTOR, class ACE_LOCK>
ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK>::ACE_Timer_Heap_T (size_t size,
                                                         int preallocate,
                                                         FUNCTOR *upcall_functor,
                                                         ACE_Free_List<ACE_Timer_Node_T <TYPE> > *freelist)
  : ACE_Timer_Queue_T<TYPE,FUNCTOR,ACE_LOCK> (upcall_functor, freelist),
    max_size_ (size),
    cur_size_ (0),
    timer_ids_freelist_ (1),
    preallocated_nodes_ (0),
    preallocated_nodes_freelist_ (0)
{
  ACE_TRACE ("ACE_Timer_Heap_T::ACE_Timer_Heap_T");

  // Create the heap array.
  ACE_NEW (this->heap_, (ACE_Timer_Node_T<TYPE> *[size]));

  // Create the parallel
  ACE_NEW (this->timer_ids_, long[size]);

  // Initialize the "freelist," which uses negative values to
  // distinguish freelist elements from "pointers" into the <heap_>
  // array.
  for (size_t i = 0; i < size; i++)
    this->timer_ids_[i] = -((long) (i + 1));

  if (preallocate)
    {
      ACE_NEW (this->preallocated_nodes_,
               (ACE_Timer_Node_T<TYPE>[size]));

      // Add allocated array to set of such arrays for deletion
      // on cleanup.
      this->preallocated_node_set_.insert (this->preallocated_nodes_);

      // Form the freelist by linking the next_ pointers together.
      for (size_t j = 1; j < size; j++)
        this->preallocated_nodes_[j - 1].set_next (&this->preallocated_nodes_[j]);

      // NULL-terminate the freelist.
      this->preallocated_nodes_[size - 1].set_next (0);

      // Assign the freelist pointer to the front of the list.
      this->preallocated_nodes_freelist_ =
        &this->preallocated_nodes_[0];
    }

  iterator_ = new HEAP_ITERATOR(*this);
}

template <class TYPE, class FUNCTOR, class ACE_LOCK>
ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK>::ACE_Timer_Heap_T (FUNCTOR *upcall_functor,
                                                         ACE_Free_List<ACE_Timer_Node_T <TYPE> > *freelist)
  : ACE_Timer_Queue_T<TYPE,FUNCTOR,ACE_LOCK> (upcall_functor, freelist),
    max_size_ (ACE_DEFAULT_TIMERS),
    cur_size_ (0),
    timer_ids_freelist_ (1),
    preallocated_nodes_ (0),
    preallocated_nodes_freelist_ (0)
{
  ACE_TRACE ("ACE_Timer_Heap_T::ACE_Timer_Heap_T");

  // Create the heap array.
  ACE_NEW (this->heap_, (ACE_Timer_Node_T<TYPE> *[this->max_size_]));

  // Create the parallel
  ACE_NEW (this->timer_ids_, long[this->max_size_]);

  // Initialize the "freelist," which uses negative values to
  // distinguish freelist elements from "pointers" into the <heap_>
  // array.
  for (size_t i = 0; i < this->max_size_; i++)
    this->timer_ids_[i] = -((long) (i + 1));

  iterator_ = new HEAP_ITERATOR(*this);
}


template <class TYPE, class FUNCTOR, class ACE_LOCK>
ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK>::~ACE_Timer_Heap_T (void)
{
  ACE_TRACE ("ACE_Timer_Heap::~ACE_Timer_Heap");

  delete iterator_;

  // Clean up all the nodes still in the queue
  for (size_t i = 0; i < this->cur_size_; i++)
    {
      this->upcall_functor ().deletion (*this,
                                        this->heap_[i]->get_type (),
                                        this->heap_[i]->get_act ());
      this->free_node (this->heap_[i]);
    }


  delete [] this->heap_;
  delete [] this->timer_ids_;

  // clean up any preallocated timer nodes
  if (preallocated_nodes_ != 0)
    {
      ACE_Unbounded_Set_Iterator<ACE_Timer_Node_T<TYPE> *>
        set_iterator (this->preallocated_node_set_);

      for (ACE_Timer_Node_T<TYPE> **entry = 0;
           set_iterator.next (entry) !=0;
           set_iterator.advance ())
        delete [] *entry;
    }
}




template <class TYPE, class FUNCTOR, class ACE_LOCK> int
ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK>::pop_freelist (void)
{
  ACE_TRACE ("ACE_Timer_Heap::pop_freelist");

  // We need to truncate this to <int> for backwards compatibility.
  int new_id = (int) this->timer_ids_freelist_;
  // The freelist values in the <timer_ids_> are negative, so we need
  // to negate them to get the next freelist "pointer."
  this->timer_ids_freelist_ = -this->timer_ids_[this->timer_ids_freelist_];
  return new_id;
}


template <class TYPE, class FUNCTOR, class ACE_LOCK> void
ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK>::push_freelist (int old_id)
{
  ACE_TRACE ("ACE_Timer_Heap::push_freelist");

  // The freelist values in the <timer_ids_> are negative, so we need
  // to negate them to get the next freelist "pointer."
  this->timer_ids_[old_id] = -this->timer_ids_freelist_;
  this->timer_ids_freelist_ = old_id;
}

template <class TYPE, class FUNCTOR, class ACE_LOCK> int
ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK>::timer_id (void)
{
  ACE_TRACE ("ACE_Timer_Heap::timer_id");

  // Return the next item off the freelist and use it as the timer id.
  return this->pop_freelist ();
}

// Checks if queue is empty.

template <class TYPE, class FUNCTOR, class ACE_LOCK> int
ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK>::is_empty (void) const
{
  ACE_TRACE ("ACE_Timer_Heap::is_empty");
  return this->cur_size_ == 0;  
}


template <class TYPE, class FUNCTOR, class ACE_LOCK> ACE_Timer_Queue_Iterator_T<TYPE, FUNCTOR, ACE_LOCK> &
ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK>::iter (void)
{
  this->iterator_->first ();
  return *this->iterator_;
}

// Returns earliest time in a non-empty queue.


template <class TYPE, class FUNCTOR, class ACE_LOCK> const ACE_Time_Value &
ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK>::earliest_time (void) const
{
  ACE_TRACE ("ACE_Timer_Heap::earliest_time");
  return this->heap_[0]->get_timer_value ();
}


template <class TYPE, class FUNCTOR, class ACE_LOCK> void
ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK>::dump (void) const
{
  ACE_TRACE ("ACE_Timer_Heap::dump");
  ACE_DEBUG ((LM_DEBUG, ACE_BEGIN_DUMP, this));

  ACE_DEBUG ((LM_DEBUG, ASYS_TEXT ("\nmax_size_ = %d"), this->max_size_));
  ACE_DEBUG ((LM_DEBUG, ASYS_TEXT ("\ncur_size_ = %d"), this->cur_size_));
  ACE_DEBUG ((LM_DEBUG, ASYS_TEXT ("\nheap_ = \n")));

  for (size_t i = 0; i < this->cur_size_; i++)
    {
      ACE_DEBUG ((LM_DEBUG, ASYS_TEXT ("%d\n"), i));
      this->heap_[i]->dump ();
    }

  ACE_DEBUG ((LM_DEBUG, ASYS_TEXT ("\ntimer_ids_ = \n")));

  for (size_t j = 0; j < this->cur_size_; j++)
    ACE_DEBUG ((LM_DEBUG, ASYS_TEXT ("%d\t%d\n"), j, this->timer_ids_[j]));

  ACE_DEBUG ((LM_DEBUG, ACE_END_DUMP));
}

template <class TYPE, class FUNCTOR, class ACE_LOCK> void
ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK>::copy (int index, ACE_Timer_Node_T<TYPE> *moved_node)
{
  // Insert <moved_node> into its new location in the heap.
  this->heap_[index] = moved_node;

  ACE_ASSERT (moved_node->get_timer_id () >= 0
              && moved_node->get_timer_id () < (int) this->max_size_);
  // Update the corresponding slot in the parallel <timer_ids_> array.
  this->timer_ids_[moved_node->get_timer_id ()] = index;
}

template <class TYPE, class FUNCTOR, class ACE_LOCK> ACE_Timer_Node_T<TYPE> *
ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK>::remove (size_t index)
{
  ACE_Timer_Node_T<TYPE> *removed_node = this->heap_[index];

  // Return this timer id to the freelist.
  this->push_freelist (removed_node->get_timer_id ());

  // Decrement the size of the heap by one since we're removing the
  // "index"th node.
  this->cur_size_--;

  // Only try to reheapify if we're not deleting the last entry.

  if (index < this->cur_size_)
    {
      ACE_Timer_Node_T<TYPE> *moved_node = this->heap_[this->cur_size_];

      // Move the end node to the location being removed and update
      // the corresponding slot in the parallel <timer_ids> array.
      this->copy (index, moved_node);

      // If the <moved_node->time_value_> is great than or equal its
      // parent it needs be moved down the heap.
      size_t parent = ACE_HEAP_PARENT (index);

      if (moved_node->get_timer_value () >= this->heap_[parent]->get_timer_value ())
        this->reheap_down (moved_node, index, ACE_HEAP_LCHILD (index));
      else
        this->reheap_up (moved_node, index, parent);
    }

  return removed_node;
}

template <class TYPE, class FUNCTOR, class ACE_LOCK> void
ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK>::reheap_down (ACE_Timer_Node_T<TYPE> *moved_node,
                                                    size_t index,
                                                    size_t child)
{
  // Restore the heap property after a deletion.

  while (child < this->cur_size_)
    {
      // Choose the smaller of the two children.
      if (child + 1 < this->cur_size_
          && this->heap_[child + 1]->get_timer_value () < this->heap_[child]->get_timer_value ())
        child++;

      // Perform a <copy> if the child has a larger timeout value than
      // the <moved_node>.
      if (this->heap_[child]->get_timer_value () < moved_node->get_timer_value ())
        {
          this->copy (index, this->heap_[child]);
          index = child;
          child = ACE_HEAP_LCHILD (child);
        }
      else
        // We've found our location in the heap.
        break;
    }

  this->copy (index, moved_node);
}

template <class TYPE, class FUNCTOR, class ACE_LOCK> void
ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK>::reheap_up (ACE_Timer_Node_T<TYPE> *moved_node,
                                                  size_t index,
                                                  size_t parent)
{
  // Restore the heap property after an insertion.

  while (index > 0)
    {
      // If the parent node is greater than the <moved_node> we need
      // to copy it down.
      if (moved_node->get_timer_value () < this->heap_[parent]->get_timer_value ())
        {
          this->copy (index, this->heap_[parent]);
          index = parent;
          parent = ACE_HEAP_PARENT (index);
        }
      else
        break;
    }

  // Insert the new node into its proper resting place in the heap and
  // update the corresponding slot in the parallel <timer_ids> array.
  this->copy (index, moved_node);
}

template <class TYPE, class FUNCTOR, class ACE_LOCK> void
ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK>::insert (ACE_Timer_Node_T<TYPE> *new_node)
{
  if (this->cur_size_ + 2 >= max_size_)
    this->grow_heap ();

  this->reheap_up (new_node,
                   this->cur_size_,
                   ACE_HEAP_PARENT (this->cur_size_));
  this->cur_size_++;
}


template <class TYPE, class FUNCTOR, class ACE_LOCK> void
ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK>::grow_heap (void)
{
  // All the containers will double in size from max_size_
  size_t new_size = max_size_ * 2;

   // First grow the heap itself.

  ACE_Timer_Node_T<TYPE> **new_heap;
  ACE_NEW (new_heap, (ACE_Timer_Node_T<TYPE> *[new_size]));
  ACE_OS::memcpy (new_heap, this->heap_,
                  max_size_ * sizeof *new_heap);
  delete [] this->heap_;
  this->heap_ = new_heap;

  // Grow the array of timer ids.

  long *new_timer_ids;

  ACE_NEW (new_timer_ids, long[new_size]);

  ACE_OS::memcpy (new_timer_ids,
                  this->timer_ids_,
                  max_size_ * sizeof (long));

  delete [] timer_ids_;
  this->timer_ids_ = new_timer_ids;

  // and add the new elements to the end of the "freelist"
  for (size_t i = this->max_size_; i < new_size; i++)
    this->timer_ids_[i] = -((long) (i + 1));

   // Grow the preallocation array (if using preallocation)
  if (this->preallocated_nodes_ != 0)
    {
      // Create a new array with max_size elements to link in
      // to existing list.
      ACE_NEW (this->preallocated_nodes_,
               (ACE_Timer_Node_T<TYPE>[this->max_size_]));

      // Add it to the set for later deletion
      this->preallocated_node_set_.insert (this->preallocated_nodes_);

      // link new nodes together (as for original list).
      for (size_t k = 1; k < this->max_size_; k++)
        this->preallocated_nodes_[k - 1].set_next (&this->preallocated_nodes_[k]);

      // NULL-terminate the new list.
      this->preallocated_nodes_[this->max_size_ - 1].set_next (0);

      // link new array to the end of the existling list
      if (this->preallocated_nodes_freelist_ == 0)
        this->preallocated_nodes_freelist_ = &preallocated_nodes_[0];
      else
        {
          ACE_Timer_Node_T<TYPE> *previous = this->preallocated_nodes_freelist_;

          for (ACE_Timer_Node_T<TYPE> *current = this->preallocated_nodes_freelist_->get_next ();
               current != 0;
               current = current->get_next ())
            previous = current;

          previous->set_next (&this->preallocated_nodes_[0]);
        }
    }

  this->max_size_ = new_size;
}

// Reschedule a periodic timer.  This function must be called with the
// mutex lock held.

template <class TYPE, class FUNCTOR, class ACE_LOCK> void
ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK>::reschedule (ACE_Timer_Node_T<TYPE> *expired)
{
  ACE_TRACE ("ACE_Timer_Heap::reschedule");

  // If we are rescheduling then we have freed our timer id so we need
  // to reacquire it.
  // NOTE: we rely on the fact that we will get the same timer id we just
  // freed.
  int timerId = this->timer_id ();

  ACE_ASSERT(timerId == expired->get_timer_id ());   // Just to be safe...

  // Restore the heap property.
  this->insert (expired);
}


template <class TYPE, class FUNCTOR, class ACE_LOCK> ACE_Timer_Node_T<TYPE> *
ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK>::alloc_node (void)
{
  ACE_Timer_Node_T<TYPE> *temp;

  // Only allocate a node if we are *not* using the preallocated heap.
  if (this->preallocated_nodes_ == 0)
    ACE_NEW_RETURN (temp,
                    (ACE_Timer_Node_T<TYPE>),
                    0);
  else
    {
      // check to see if the heap needs to grow
      if (this->preallocated_nodes_freelist_ == 0)
        this->grow_heap ();

      temp = this->preallocated_nodes_freelist_;

      // Remove the first element from the freelist.
      this->preallocated_nodes_freelist_ =
        this->preallocated_nodes_freelist_->get_next ();
    }
  return temp;
}


template <class TYPE, class FUNCTOR, class ACE_LOCK> void
ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK>::free_node (ACE_Timer_Node_T<TYPE> *node)
{
  // Only free up a node if we are *not* using the preallocated heap.
  if (this->preallocated_nodes_ == 0)
    delete node;
  else
    {
      node->set_next (this->preallocated_nodes_freelist_);
      this->preallocated_nodes_freelist_ = node;
    }
}

// Insert a new timer that expires at time future_time; if interval is
// > 0, the handler will be reinvoked periodically.


template <class TYPE, class FUNCTOR, class ACE_LOCK> long
ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK>::schedule (const TYPE &type,
                                                 const void *act,
                                                 const ACE_Time_Value &future_time,
                                                 const ACE_Time_Value &interval)
{
  ACE_TRACE ("ACE_Timer_Heap::schedule");

  ACE_MT (ACE_GUARD_RETURN (ACE_LOCK, ace_mon, this->mutex_, -1));

  if (this->cur_size_ < this->max_size_)
    {
      // Obtain the next unique sequence number.
      int timer_id = this->timer_id ();

      // Obtain the memory to the new node.
      ACE_Timer_Node_T<TYPE> *temp = this->alloc_node ();

      if (temp)
        {
          temp->set (type,
                     act,
                     future_time,
                     interval,
                     0,
                     timer_id);

          this->insert (temp);
          return timer_id;
        }
    }
  // Failure return.
  errno = ENOMEM;
  return -1;
}

// Locate and remove the single timer with a value of <timer_id> from
// the timer queue.

template <class TYPE, class FUNCTOR, class ACE_LOCK> int
ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK>::cancel (long timer_id,
                                               const void **act,
                                               int dont_call)
{
  ACE_TRACE ("ACE_Timer_Heap::cancel");
  ACE_MT (ACE_GUARD_RETURN (ACE_LOCK, ace_mon, this->mutex_, -1));

  // Locate the ACE_Timer_Node that corresponds to the timer_id.

  // Check to see if the timer_id is out of range
  if (timer_id < 0 || (size_t)timer_id > this->max_size_)
    return 0;

  long timer_node_slot = this->timer_ids_[timer_id];

  if (timer_node_slot < 0) // Check to see if timer_id is still valid.
    return 0;

  if (timer_id != this->heap_[timer_node_slot]->get_timer_id ())
    {
      ACE_ASSERT (timer_id == this->heap_[timer_node_slot]->get_timer_id ());
      return 0;
    }
  else
    {
      ACE_Timer_Node_T<TYPE> *temp = this->remove (timer_node_slot);

      if (dont_call == 0)
        // Call the close hook.
        this->upcall_functor ().cancellation (*this, temp->get_type ());

      if (act != 0)
        *act = temp->get_act ();

      this->free_node (temp);
      return 1;
    }
}

// Locate and remove all values of <type> from the timer queue.

template <class TYPE, class FUNCTOR, class ACE_LOCK> int
ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK>::cancel (const TYPE &type,
                                               int dont_call)
{
  ACE_TRACE ("ACE_Timer_Heap::cancel");
  ACE_MT (ACE_GUARD_RETURN (ACE_LOCK, ace_mon, this->mutex_, -1));

  int number_of_cancellations = 0;

  // Try to locate the ACE_Timer_Node that matches the timer_id.

  for (size_t i = 0; i < this->cur_size_; )
    {
      if (this->heap_[i]->get_type () == type)
        {
          ACE_Timer_Node_T<TYPE> *temp = this->remove (i);

          number_of_cancellations++;

          this->free_node (temp);
        }
      else
        i++;
    }

  if (dont_call == 0)
    this->upcall_functor ().cancellation (*this, type);

  return number_of_cancellations;
}


// Returns the earliest node or returns 0 if the heap is empty.

template <class TYPE, class FUNCTOR, class ACE_LOCK> ACE_Timer_Node_T <TYPE> *
ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK>::remove_first (void)
{
  ACE_TRACE ("ACE_Timer_Heap_T::remove_first");

  if (this->cur_size_ == 0)
    return 0;

  return this->remove (0);
}

template <class TYPE, class FUNCTOR, class ACE_LOCK> ACE_Timer_Node_T <TYPE> *
ACE_Timer_Heap_T<TYPE, FUNCTOR, ACE_LOCK>::get_first (void)
{
  ACE_TRACE ("ACE_Timer_Heap_T::get_first");

  return this->cur_size_ == 0  ?  0  :  this->heap_[0];
}

#endif /* ACE_TIMER_HEAP_T_C */