// $Id: Timer_Queue_T.cpp 92285 2010-10-20 16:34:57Z shuston $

#ifndef ACE_TIMER_QUEUE_T_CPP
#define ACE_TIMER_QUEUE_T_CPP

#include "ace/config-all.h"

#if !defined (ACE_LACKS_PRAGMA_ONCE)
# pragma once
#endif /* ACE_LACKS_PRAGMA_ONCE */

/*
 * Hook to specialize to add includes
 */
//@@ REACTOR_SPL_INCLUDE_FORWARD_DECL_ADD_HOOK

#include "ace/Timer_Queue_T.h"
#include "ace/Guard_T.h"
#include "ace/Log_Msg.h"
#include "ace/Reactor_Timer_Interface.h"
#include "ace/Reverse_Lock_T.h"
#include "ace/Null_Mutex.h"
#include "ace/OS_NS_sys_time.h"

#if !defined (__ACE_INLINE__)
#include "ace/Timer_Queue_T.inl"
#endif /* __ACE_INLINE__ */

ACE_BEGIN_VERSIONED_NAMESPACE_DECL

// This fudge factor can be overriden for timers that need it, such as on
// Solaris, by defining the ACE_TIMER_SKEW symbol in the appropriate config
// header.
#if !defined (ACE_TIMER_SKEW)
#  define ACE_TIMER_SKEW 0
#endif /* ACE_TIMER_SKEW */

template <class TYPE> void
ACE_Timer_Node_T<TYPE>::dump (void) const
{
#if defined (ACE_HAS_DUMP)
  ACE_TRACE ("ACE_Timer_Node_T::dump");
  ACE_DEBUG ((LM_DEBUG, ACE_BEGIN_DUMP, this));
  ACE_DEBUG ((LM_DEBUG, ACE_TEXT ("\nact_ = %x"), this->act_));
  this->timer_value_.dump ();
  this->interval_.dump ();
  ACE_DEBUG ((LM_DEBUG, ACE_TEXT ("\nprev_ = %x"), this->prev_));
  ACE_DEBUG ((LM_DEBUG, ACE_TEXT ("\nnext_ = %x"), this->next_));
  ACE_DEBUG ((LM_DEBUG, ACE_TEXT ("\ntimer_id_ = %d\n"), this->timer_id_));
  ACE_DEBUG ((LM_DEBUG, ACE_END_DUMP));
#endif /* ACE_HAS_DUMP */
}

template <class TYPE>
ACE_Timer_Node_T<TYPE>::ACE_Timer_Node_T (void)
{
  ACE_TRACE ("ACE_Timer_Node_T::ACE_Timer_Node_T");
}

template <class TYPE>
ACE_Timer_Node_T<TYPE>::~ACE_Timer_Node_T (void)
{
  ACE_TRACE ("ACE_Timer_Node_T::~ACE_Timer_Node_T");
}

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

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

template <class TYPE, class FUNCTOR, class ACE_LOCK> ACE_Time_Value *
ACE_Timer_Queue_T<TYPE, FUNCTOR, ACE_LOCK>::calculate_timeout (ACE_Time_Value *max_wait_time)
{
  ACE_TRACE ("ACE_Timer_Queue_T::calculate_timeout");
  ACE_MT (ACE_GUARD_RETURN (ACE_LOCK, ace_mon, this->mutex_, max_wait_time));

  if (this->is_empty ())
    // Nothing on the Timer_Queue, so use whatever the caller gave us.
    return max_wait_time;
  else
    {
      ACE_Time_Value const cur_time = this->gettimeofday ();

      if (this->earliest_time () > cur_time)
        {
          // The earliest item on the Timer_Queue is still in the
          // future.  Therefore, use the smaller of (1) caller's wait
          // time or (2) the delta time between now and the earliest
          // time on the Timer_Queue.

          this->timeout_ = this->earliest_time () - cur_time;
          if (max_wait_time == 0 || *max_wait_time > timeout_)
            return &this->timeout_;
          else
            return max_wait_time;
        }
      else
        {
          // The earliest item on the Timer_Queue is now in the past.
          // Therefore, we've got to "poll" the Reactor, i.e., it must
          // just check the descriptors and then dispatch timers, etc.
          this->timeout_ = ACE_Time_Value::zero;
          return &this->timeout_;
        }
    }
}

template <class TYPE, class FUNCTOR, class ACE_LOCK> ACE_Time_Value *
ACE_Timer_Queue_T<TYPE, FUNCTOR, ACE_LOCK>::calculate_timeout (ACE_Time_Value *max_wait_time,
                                                               ACE_Time_Value *the_timeout)
{
  ACE_TRACE ("ACE_Timer_Queue_T::calculate_timeout");

  if (the_timeout == 0)
    return 0;

  if (this->is_empty ())
    {
      // Nothing on the Timer_Queue, so use whatever the caller gave us.
      if (max_wait_time)
        *the_timeout = *max_wait_time;
      else
        return 0;
    }
  else
    {
      ACE_Time_Value cur_time = this->gettimeofday ();

      if (this->earliest_time () > cur_time)
        {
          // The earliest item on the Timer_Queue is still in the
          // future.  Therefore, use the smaller of (1) caller's wait
          // time or (2) the delta time between now and the earliest
          // time on the Timer_Queue.

          *the_timeout = this->earliest_time () - cur_time;
          if (!(max_wait_time == 0 || *max_wait_time > *the_timeout))
            *the_timeout = *max_wait_time;
        }
      else
        {
          // The earliest item on the Timer_Queue is now in the past.
          // Therefore, we've got to "poll" the Reactor, i.e., it must
          // just check the descriptors and then dispatch timers, etc.
          *the_timeout = ACE_Time_Value::zero;
        }
    }
  return the_timeout;
}

template <class TYPE, class FUNCTOR, class ACE_LOCK> void
ACE_Timer_Queue_T<TYPE, FUNCTOR, ACE_LOCK>::dump (void) const
{
#if defined (ACE_HAS_DUMP)
  ACE_TRACE ("ACE_Timer_Queue_T::dump");
  ACE_DEBUG ((LM_DEBUG, ACE_BEGIN_DUMP, this));
  this->timeout_.dump ();
  this->timer_skew_.dump ();
  ACE_DEBUG ((LM_DEBUG, ACE_END_DUMP));
#endif /* ACE_HAS_DUMP */
}

template <class TYPE, class FUNCTOR, class ACE_LOCK>
ACE_Timer_Queue_T<TYPE, FUNCTOR, ACE_LOCK>::ACE_Timer_Queue_T (FUNCTOR *upcall_functor,
                                                               ACE_Free_List<ACE_Timer_Node_T <TYPE> > *freelist)
  : gettimeofday_ (ACE_OS::gettimeofday),
    delete_upcall_functor_ (upcall_functor == 0),
    delete_free_list_ (freelist == 0),
    timer_skew_ (0, ACE_TIMER_SKEW)
{
  ACE_TRACE ("ACE_Timer_Queue_T::ACE_Timer_Queue_T");

  if (!freelist)
    ACE_NEW (free_list_,
             (ACE_Locked_Free_List<ACE_Timer_Node_T<TYPE>,ACE_Null_Mutex>));
  else
    free_list_ = freelist;

  if (!upcall_functor)
    ACE_NEW (upcall_functor_,
             FUNCTOR);
  else
    upcall_functor_ = upcall_functor;
}

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

  // Cleanup the functor and free_list on the way out
  if (this->delete_upcall_functor_)
    delete this->upcall_functor_;

  if (this->delete_free_list_)
    delete this->free_list_;
}

template <class TYPE, class FUNCTOR, class ACE_LOCK> ACE_Timer_Node_T<TYPE> *
ACE_Timer_Queue_T<TYPE, FUNCTOR, ACE_LOCK>::alloc_node (void)
{
  return this->free_list_->remove ();
}

template <class TYPE, class FUNCTOR, class ACE_LOCK> void
ACE_Timer_Queue_T<TYPE, FUNCTOR, ACE_LOCK>::free_node (ACE_Timer_Node_T<TYPE> *node)
{
  this->free_list_->add (node);
}

template <class TYPE, class FUNCTOR, class ACE_LOCK> ACE_LOCK &
ACE_Timer_Queue_T<TYPE, FUNCTOR, ACE_LOCK>::mutex (void)
{
  return this->mutex_;
}

template <class TYPE, class FUNCTOR, class ACE_LOCK> long
ACE_Timer_Queue_T<TYPE, FUNCTOR, ACE_LOCK>::schedule (const TYPE &type,
                                                      const void *act,
                                                      const ACE_Time_Value &future_time,
                                                      const ACE_Time_Value &interval)
{
  ACE_MT (ACE_GUARD_RETURN (ACE_LOCK, ace_mon, this->mutex_, -1));

  // Schedule the timer.
  long const result =
    this->schedule_i (type,
                      act,
                      future_time,
                      interval);

  // Return on failure.
  if (result == -1)
    return result;

  // Inform upcall functor of successful registration.
  this->upcall_functor ().registration (*this,
                                        type,
                                        act);

  // Return result;
  return result;
}

// Run the <handle_timeout> method for all Timers whose values are <=
// <cur_time>.
template <class TYPE, class FUNCTOR, class ACE_LOCK> int
ACE_Timer_Queue_T<TYPE, FUNCTOR, ACE_LOCK>::expire (const ACE_Time_Value &cur_time)
{
  ACE_TRACE ("ACE_Timer_Queue_T::expire");
  ACE_MT (ACE_GUARD_RETURN (ACE_LOCK, ace_mon, this->mutex_, -1));

  // Keep looping while there are timers remaining and the earliest
  // timer is <= the <cur_time> passed in to the method.

  if (this->is_empty ())
    return 0;

  int number_of_timers_expired = 0;
  int result = 0;

  ACE_Timer_Node_Dispatch_Info_T<TYPE> info;

  while ((result = this->dispatch_info_i (cur_time, info)) != 0)
    {
      ACE_MT (ACE_Reverse_Lock<ACE_LOCK> rev_lk(this->mutex_));
      ACE_MT (ACE_GUARD_RETURN (ACE_Reverse_Lock<ACE_LOCK>, rmon, rev_lk, -1));

      const void *upcall_act = 0;

      this->preinvoke (info, cur_time, upcall_act);

      this->upcall (info, cur_time);

      this->postinvoke (info, cur_time, upcall_act);

      ++number_of_timers_expired;

    }

  ACE_UNUSED_ARG (result);
  return number_of_timers_expired;
}

template <class TYPE, class FUNCTOR, class ACE_LOCK> void
ACE_Timer_Queue_T<TYPE, FUNCTOR, ACE_LOCK>::recompute_next_abs_interval_time
    (ACE_Timer_Node_T<TYPE> *expired,
     const ACE_Time_Value &cur_time)
{
  if ( expired->get_timer_value () <= cur_time )
    {
      /*
       * Somehow the current time is past when this time was
       * supposed to expire (e.g., timer took too long,
       * somebody changed system time, etc.).  There used to
       * be a simple loop here that skipped ahead one timer
       * interval at a time, but that was horribly inefficient
       * (an O(n) algorithm) when the timer duration was small
       * relative to the amount of time skipped.
       *
       * So, we replace the loop with a simple computation,
       * which also happens to be O(1).  All times get
       * normalized in the computation to microseconds.
       *
       * For reference, the loop looked like this:
       *
       *   do
       *     expired->set_timer_value (expired->get_timer_value () +
       *                               expired->get_interval ());
       *   while (expired->get_timer_value () <= cur_time);
       *
       */

      // Compute the duration of the timer's interval
      ACE_UINT64 interval_usec;
      expired->get_interval ().to_usec (interval_usec);

      // Compute the span between the current time and when
      // the timer would have expired in the past (and
      // normalize to microseconds).
      ACE_Time_Value old_diff = cur_time - expired->get_timer_value ();
      ACE_UINT64 old_diff_usec;
      old_diff.to_usec (old_diff_usec);

      // Compute the delta time in the future when the timer
      // should fire as if it had advanced incrementally.  The
      // modulo arithmetic accomodates the likely case that
      // the current time doesn't fall precisely on a timer
      // firing interval.
      ACE_UINT64 new_timer_usec =
        interval_usec - (old_diff_usec % interval_usec);

      // Compute the absolute time in the future when this
      // interval timer should expire.
      ACE_Time_Value new_timer_value
        (cur_time.sec ()
         + static_cast<time_t>(new_timer_usec / ACE_ONE_SECOND_IN_USECS),
         cur_time.usec ()
         + static_cast<suseconds_t>(new_timer_usec % ACE_ONE_SECOND_IN_USECS));

      expired->set_timer_value (new_timer_value);
    }
}

template <class TYPE, class FUNCTOR, class ACE_LOCK> int
ACE_Timer_Queue_T<TYPE, FUNCTOR, ACE_LOCK>::dispatch_info_i (const ACE_Time_Value &cur_time,
                                                             ACE_Timer_Node_Dispatch_Info_T<TYPE> &info)
{
  ACE_TRACE ("ACE_Timer_Queue_T::dispatch_info_i");

  if (this->is_empty ())
    return 0;

  ACE_Timer_Node_T<TYPE> *expired = 0;

  if (this->earliest_time () <= cur_time)
    {
      expired = this->remove_first ();

      // Get the dispatch info
      expired->get_dispatch_info (info);

      // Check if this is an interval timer.
      if (expired->get_interval () > ACE_Time_Value::zero)
        {
          // Make sure that we skip past values that have already
          // "expired".
          this->recompute_next_abs_interval_time (expired, cur_time);

          // Since this is an interval timer, we need to reschedule
          // it.
          this->reschedule (expired);
        }
      else
        {
          // Call the factory method to free up the node.
          this->free_node (expired);
        }

      return 1;
    }

  return 0;
}

template <class TYPE, class FUNCTOR, class ACE_LOCK> void
ACE_Timer_Queue_T<TYPE, FUNCTOR, ACE_LOCK>::return_node (ACE_Timer_Node_T<TYPE> *node)
{
  ACE_MT (ACE_GUARD (ACE_LOCK, ace_mon, this->mutex_));
  this->free_node (node);
}


template <class ACE_LOCK>
ACE_Event_Handler_Handle_Timeout_Upcall<ACE_LOCK>::ACE_Event_Handler_Handle_Timeout_Upcall (void)
{
}

template <class ACE_LOCK>
ACE_Event_Handler_Handle_Timeout_Upcall<ACE_LOCK>::~ACE_Event_Handler_Handle_Timeout_Upcall (void)
{
}

template <class ACE_LOCK> int
ACE_Event_Handler_Handle_Timeout_Upcall<ACE_LOCK>::registration (TIMER_QUEUE &,
                                                                 ACE_Event_Handler *event_handler,
                                                                 const void *)
{
  event_handler->add_reference ();
  return 0;
}

template <class ACE_LOCK> int
ACE_Event_Handler_Handle_Timeout_Upcall<ACE_LOCK>::preinvoke (TIMER_QUEUE & /* timer_queue */,
                                                              ACE_Event_Handler *event_handler,
                                                              const void * /* timer_act */,
                                                              int /* recurring_timer */,
                                                              const ACE_Time_Value & /* cur_time */,
                                                              const void *&upcall_act)
{
  bool const requires_reference_counting =
    event_handler->reference_counting_policy ().value () ==
    ACE_Event_Handler::Reference_Counting_Policy::ENABLED;

  if (requires_reference_counting)
    {
      event_handler->add_reference ();

      upcall_act = &this->requires_reference_counting_;
    }

  return 0;
}

template <class ACE_LOCK> int
ACE_Event_Handler_Handle_Timeout_Upcall<ACE_LOCK>::postinvoke (TIMER_QUEUE & /* timer_queue */,
                                                               ACE_Event_Handler *event_handler,
                                                               const void * /* timer_act */,
                                                               int /* recurring_timer */,
                                                               const ACE_Time_Value & /* cur_time */,
                                                               const void *upcall_act)
{
  if (upcall_act == &this->requires_reference_counting_)
    {
      event_handler->remove_reference ();
    }

  return 0;
}

template <class ACE_LOCK> int
ACE_Event_Handler_Handle_Timeout_Upcall<ACE_LOCK>::timeout (TIMER_QUEUE &timer_queue,
                                                            ACE_Event_Handler *event_handler,
                                                            const void *act,
                                                            int recurring_timer,
                                                            const ACE_Time_Value &cur_time)
{
  int requires_reference_counting = 0;

  if (!recurring_timer)
    {
      requires_reference_counting =
        event_handler->reference_counting_policy ().value () ==
        ACE_Event_Handler::Reference_Counting_Policy::ENABLED;
    }

  // Upcall to the <handler>s handle_timeout method.
  if (event_handler->handle_timeout (cur_time, act) == -1)
    {
      if (event_handler->reactor_timer_interface ())
        event_handler->reactor_timer_interface ()->cancel_timer (event_handler, 0);
      else
        timer_queue.cancel (event_handler, 0); // 0 means "call handle_close()".
    }

  if (!recurring_timer &&
      requires_reference_counting)
    {
      event_handler->remove_reference ();
    }

  return 0;
}

template <class ACE_LOCK> int
ACE_Event_Handler_Handle_Timeout_Upcall<ACE_LOCK>::cancel_type (TIMER_QUEUE &,
                                                                ACE_Event_Handler *event_handler,
                                                                int dont_call,
                                                                int &requires_reference_counting)
{
  requires_reference_counting =
    event_handler->reference_counting_policy ().value () ==
    ACE_Event_Handler::Reference_Counting_Policy::ENABLED;

  // Upcall to the <handler>s handle_close method
  if (dont_call == 0)
    event_handler->handle_close (ACE_INVALID_HANDLE,
                                 ACE_Event_Handler::TIMER_MASK);

  return 0;
}

template <class ACE_LOCK> int
ACE_Event_Handler_Handle_Timeout_Upcall<ACE_LOCK>::cancel_timer (TIMER_QUEUE &,
                                                                 ACE_Event_Handler *event_handler,
                                                                 int,
                                                                 int requires_reference_counting)
{
  if (requires_reference_counting)
    event_handler->remove_reference ();

  return 0;
}

template <class ACE_LOCK> int
ACE_Event_Handler_Handle_Timeout_Upcall<ACE_LOCK>::deletion (TIMER_QUEUE &timer_queue,
                                                             ACE_Event_Handler *event_handler,
                                                             const void *)
{
  int requires_reference_counting = 0;

  this->cancel_type (timer_queue,
                     event_handler,
                     0,
                     requires_reference_counting);

  this->cancel_timer (timer_queue,
                      event_handler,
                      0,
                      requires_reference_counting);

  return 0;
}

ACE_END_VERSIONED_NAMESPACE_DECL

#endif /* ACE_TIMER_QUEUE_T_CPP */
