Transport_Cache_Manager_T.cpp

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//$Id: Transport_Cache_Manager_T.cpp 90455 2010-06-08 09:09:16Z johnnyw $
#include "tao/Transport_Cache_Manager_T.h"
#include "tao/debug.h"
#include "tao/Connection_Purging_Strategy.h"
#include "tao/Client_Strategy_Factory.h"
#include "tao/Condition.h"
#include "tao/Wait_Strategy.h"
#include "ace/ACE.h"
#include "ace/Reactor.h"
#include "ace/Lock_Adapter_T.h"

#if !defined (__ACE_INLINE__)
# include "tao/Transport_Cache_Manager_T.inl"
#endif /* __ACE_INLINE__ */

ACE_RCSID (tao,
           Transport_Cache_Manager_T,
           "$Id: Transport_Cache_Manager_T.cpp 90455 2010-06-08 09:09:16Z johnnyw $")

// notes on debug level and LM_xxxx codes for transport cache
// TAO_debug_level > 0: recoverable error condition (LM_ERROR)
// TAO_debug_level > 4: normal transport cache operations (LM_INFO)
// TAO_debug_level > 6: detailed cache operations (LM_DEBUG)
// TAO_debug_level > 8: for debugging the cache itself (LM_DEBUG)


TAO_BEGIN_VERSIONED_NAMESPACE_DECL

namespace TAO
{
  template <typename TT, typename TRDT, typename PSTRAT>
  Transport_Cache_Manager_T<TT, TRDT, PSTRAT>::Transport_Cache_Manager_T (
    int percent,
    purging_strategy* purging_strategy,
    size_t cache_maximum,
    bool locked,
    const char *orbid)
    : percent_ (percent)
    , purging_strategy_ (purging_strategy)
    , cache_map_ (cache_maximum)
    , cache_lock_ (0)
    , cache_maximum_ (cache_maximum)
#if defined (TAO_HAS_MONITOR_POINTS) && (TAO_HAS_MONITOR_POINTS == 1)
    , purge_monitor_ (0)
    , size_monitor_ (0)
#endif /* TAO_HAS_MONITOR_POINTS==1 */
  {
    if (locked)
      {
        ACE_NEW (this->cache_lock_,
                 ACE_Lock_Adapter <TAO_SYNCH_MUTEX> (this->cache_map_mutex_));
      }
    else
      {
        ACE_NEW (this->cache_lock_,
                 ACE_Lock_Adapter<ACE_SYNCH_NULL_MUTEX>);
      }

#if defined (TAO_HAS_MONITOR_POINTS) && (TAO_HAS_MONITOR_POINTS == 1)
    ACE_NEW (this->purge_monitor_,
             ACE::Monitor_Control::Size_Monitor);
    ACE_NEW (this->size_monitor_,
             ACE::Monitor_Control::Size_Monitor);

    ACE_CString purge_name ("Connection_Cache_Purge_");
    ACE_CString size_name ("Connection_Cache_Size_");

    purge_name += orbid;
    size_name += orbid;

    this->purge_monitor_->name (purge_name.c_str ());
    this->size_monitor_->name (size_name.c_str ());

    this->purge_monitor_->add_to_registry ();
    this->size_monitor_->add_to_registry ();
#else
  ACE_UNUSED_ARG (orbid);
#endif /* TAO_HAS_MONITOR_POINTS==1 */
  }

  template <typename TT, typename TRDT, typename PSTRAT>
  Transport_Cache_Manager_T<TT, TRDT, PSTRAT>::~Transport_Cache_Manager_T (void)
  {
    delete this->cache_lock_;
    this->cache_lock_ = 0;

    delete this->purging_strategy_;
    this->purging_strategy_ = 0;

#if defined (TAO_HAS_MONITOR_POINTS) && (TAO_HAS_MONITOR_POINTS == 1)
    this->purge_monitor_->remove_from_registry ();
    this->size_monitor_->remove_from_registry ();
    this->purge_monitor_->remove_ref ();
    this->size_monitor_->remove_ref ();
#endif /* TAO_HAS_MONITOR_POINTS==1 */
  }

  template <typename TT, typename TRDT, typename PSTRAT>
  void
  Transport_Cache_Manager_T<TT, TRDT, PSTRAT>::set_entry_state (HASH_MAP_ENTRY *entry,
                                            TAO::Cache_Entries_State state)
  {
    ACE_MT (ACE_GUARD (ACE_Lock, guard, *this->cache_lock_));
    if (entry != 0)
      {
        entry->item ().recycle_state (state);
        if (state != ENTRY_UNKNOWN && state != ENTRY_CONNECTING
            && entry->item ().transport ())
          entry->item ().is_connected (
            entry->item ().transport ()->is_connected ());
      }
  }

  template <typename TT, typename TRDT, typename PSTRAT>
  int
  Transport_Cache_Manager_T<TT, TRDT, PSTRAT>::bind_i (
    Cache_ExtId &ext_id,
    Cache_IntId &int_id)
  {
    if (TAO_debug_level > 4)
       {
         ACE_DEBUG ((LM_INFO,
            ACE_TEXT ("TAO (%P|%t) - Transport_Cache_Manager_T::bind_i, ")
            ACE_TEXT ("Transport[%d] @ hash:index{%d:%d}\n"),
            int_id.transport ()->id (),
            ext_id.hash (),
            ext_id.index ()
            ));
       }

    // Get the entry too
    HASH_MAP_ENTRY *entry = 0;

    // Update the purging strategy information while we
    // are holding our lock
    this->purging_strategy_->update_item (int_id.transport ());
    int retval = 0;
    bool more_to_do = true;
    while (more_to_do)
      {
        if (this->cache_map_.current_size () >= cache_maximum_)
          {
            retval = -1;
            if (TAO_debug_level > 0)
              {
                ACE_ERROR ((LM_ERROR,
                  ACE_TEXT("TAO (%P|%t) - Transport_Cache_Manager_T::bind_i, ")
                  ACE_TEXT("ERROR: unable to bind transport, cache is full\n")));
              }
            more_to_do = false;
          }
        else
          {
            retval = this->cache_map_.bind (ext_id, int_id, entry);
            if (retval == 0)
              {
                // The entry has been added to cache succesfully
                // Add the cache_map_entry to the transport
                int_id.transport ()->cache_map_entry (entry);
                more_to_do = false;
              }
            else if (retval == 1)
              {
                if (entry->item ().transport () == int_id.transport ())
                  {
                    // update the cache status
                    // we are already holding the lock, do not call set_entry_state
                    entry->item ().recycle_state (int_id.recycle_state ());
                    if (TAO_debug_level > 9 &&
                        entry->item ().is_connected () != int_id.is_connected ())
                      ACE_DEBUG ((LM_DEBUG,
                                  ACE_TEXT ("TAO (%P|%t) - Transport_Cache_")
                                  ACE_TEXT ("Manager::bind_i, Updating existing ")
                                  ACE_TEXT ("entry sets is_connected to %C\n"),
                                  (int_id.is_connected () ? "true" : "false")));

                    entry->item ().is_connected (int_id.is_connected ());
                    retval = 0;
                    more_to_do = false;
                  }
                else
                {
                  ext_id.index (ext_id.index () + 1);
                  if (TAO_debug_level > 8)
                    {
                      ACE_DEBUG ((LM_DEBUG,
                        ACE_TEXT ("TAO (%P|%t) - Transport_Cache_Manager_T::bind_i, ")
                        ACE_TEXT ("Unable to bind Transport[%d] @ hash:index{%d:%d}. ")
                        ACE_TEXT ("Trying with a new index\n"),
                        int_id.transport ()->id (),
                        ext_id.hash (),
                        ext_id.index ()));
                    }
                }
              }
            else
              {
                if (TAO_debug_level > 0)
                  {
                    ACE_ERROR ((LM_ERROR,
                      ACE_TEXT("TAO (%P|%t) - Transport_Cache_Manager_T::bind_i, ")
                      ACE_TEXT("ERROR: unable to bind transport\n")));
                  }
                more_to_do = false;
              }
          }
      }
    if (retval == 0)
      {
        if (TAO_debug_level > 4)
          {
            ACE_DEBUG ((LM_INFO,
              ACE_TEXT ("TAO (%P|%t) - Transport_Cache_Manager_T::bind_i: ")
              ACE_TEXT ("Success Transport[%d] @ hash:index{%d:%d}. ")
              ACE_TEXT ("Cache size is [%d]\n"),
              int_id.transport ()->id (),
              ext_id.hash (),
              ext_id.index (),
              this->current_size ()
              ));
          }
      }

#if defined (TAO_HAS_MONITOR_POINTS) && (TAO_HAS_MONITOR_POINTS == 1)
    this->size_monitor_->receive (this->current_size ());
#endif /* TAO_HAS_MONITOR_POINTS==1 */

    return retval;
  }

  template <typename TT, typename TRDT, typename PSTRAT>
  typename Transport_Cache_Manager_T<TT, TRDT, PSTRAT>::Find_Result
  Transport_Cache_Manager_T<TT, TRDT, PSTRAT>::find_transport (
    transport_descriptor_type *prop,
    transport_type *&transport,
    size_t &busy_count)
  {
    if (prop == 0)
      {
        transport = 0;
        return CACHE_FOUND_NONE;
      }

    Find_Result find_result = this->find (
      prop, transport, busy_count);
    if (find_result != CACHE_FOUND_NONE)
      {
        if (find_result == CACHE_FOUND_AVAILABLE)
          {
            if (transport->wait_strategy ()->non_blocking () == 0 &&
                transport->orb_core ()->client_factory ()->use_cleanup_options ())
              {
                ACE_Event_Handler * const eh =
                  transport->event_handler_i ();

                ACE_Reactor * const r =
                  transport->orb_core ()->reactor ();

                if (eh &&
                    r->remove_handler (eh,
                                       ACE_Event_Handler::READ_MASK |
                                       ACE_Event_Handler::DONT_CALL) == -1)
                  {
                    if (TAO_debug_level > 0)
                      ACE_ERROR ((LM_ERROR,
                                  ACE_TEXT ("TAO (%P|%t) - Transport_Cache_Manager_T[%d]")
                                  ACE_TEXT ("::find_transport, remove_handler failed\n"),
                                  transport->id ()));
                  }
                else
                  {
                    transport->wait_strategy ()->is_registered (false);
                  }
              }
          }
      }
    return find_result;
  }

  template <typename TT, typename TRDT, typename PSTRAT>
  typename Transport_Cache_Manager_T<TT, TRDT, PSTRAT>::Find_Result
  Transport_Cache_Manager_T<TT, TRDT, PSTRAT>::find_i (
    transport_descriptor_type *prop,
    transport_type *&transport,
    size_t &busy_count)
  {
    // Get the entry from the Hash Map
    Find_Result found = CACHE_FOUND_NONE;

    // Make a temporary object. It does not do a copy.
    Cache_ExtId key (prop);
    HASH_MAP_ENTRY *entry = 0;
    busy_count = 0;
    int cache_status = 0;
    HASH_MAP_ENTRY *found_entry = 0;

    // loop until we find a usable transport, or until we've checked
    // all cached entries for this endpoint
    while (found != CACHE_FOUND_AVAILABLE && cache_status == 0)
      {
        entry = 0;
        cache_status = this->cache_map_.find (key, entry);
        if (cache_status == 0 && entry)
          {
            if (this->is_entry_available_i (*entry))
              {
                // Successfully found a transport_type.

                found = CACHE_FOUND_AVAILABLE;
                found_entry = entry;
                entry->item ().recycle_state (ENTRY_BUSY);

                if (TAO_debug_level > 6)
                  {
                    ACE_DEBUG ((LM_DEBUG,
                      ACE_TEXT ("TAO (%P|%t) - Transport_Cache_Manager_T::find_i, ")
                      ACE_TEXT ("Found available Transport[%d] @hash:index {%d:%d}\n"),
                      entry->item ().transport ()->id (),
                      entry->ext_id_.hash (),
                      entry->ext_id_.index ()
                      ));
                  }
              }
            else if (this->is_entry_connecting_i (*entry))
              {
                if (TAO_debug_level > 6)
                  {
                    ACE_DEBUG ((LM_DEBUG,
                      ACE_TEXT ("TAO (%P|%t) - Transport_Cache_Manager_T::find_i, ")
                      ACE_TEXT ("Found connecting Transport[%d] @hash:index {%d:%d}\n"),
                      entry->item ().transport ()->id (),
                      entry->ext_id_.hash (),
                      entry->ext_id_.index ()
                      ));
                  }
                // if this is the first interesting entry
                if (found != CACHE_FOUND_CONNECTING)
                  {
                    found_entry = entry;
                    found = CACHE_FOUND_CONNECTING;
                  }
              }
            else
              {
                // if this is the first busy entry
                if (found == CACHE_FOUND_NONE && busy_count == 0)
                  {
                    found_entry = entry;
                    found = CACHE_FOUND_BUSY;
                  }
                ++busy_count;
                if (TAO_debug_level > 6)
                  {
                    ACE_DEBUG ((LM_DEBUG,
                      ACE_TEXT ("TAO (%P|%t) - Transport_Cache_Manager_T::find_i, ")
                      ACE_TEXT ("Found busy Transport[%d] @hash:index {%d:%d}\n"),
                      entry->item ().transport ()->id (),
                      entry->ext_id_.hash (),
                      entry->ext_id_.index ()
                      ));
                  }
              }
          }

        // Bump the index up
        key.incr_index ();
      }
    if (found_entry != 0)
    {
      transport = found_entry->item ().transport ();
      transport->add_reference ();
      if (found == CACHE_FOUND_AVAILABLE)
        {
          // Update the purging strategy information while we
          // are holding our lock
          this->purging_strategy_->update_item (transport);
        }
    }
    return found;
  }

  template <typename TT, typename TRDT, typename PSTRAT>
  int
  Transport_Cache_Manager_T<TT, TRDT, PSTRAT>::make_idle_i (HASH_MAP_ENTRY *entry)
  {
    if (entry == 0)
      return -1;

    entry->item ().recycle_state (ENTRY_IDLE_AND_PURGABLE);

    return 0;
  }

  template <typename TT, typename TRDT, typename PSTRAT>
  int
  Transport_Cache_Manager_T<TT, TRDT, PSTRAT>::update_entry (HASH_MAP_ENTRY *&entry)
  {
    ACE_MT (ACE_GUARD_RETURN (ACE_Lock,
                              guard,
                              *this->cache_lock_, -1));

    if (entry == 0)
      return -1;

    purging_strategy *st = this->purging_strategy_;
    (void) st->update_item (entry->item ().transport ());

    return 0;
  }

  template <typename TT, typename TRDT, typename PSTRAT>
  int
  Transport_Cache_Manager_T<TT, TRDT, PSTRAT>::close_i (Connection_Handler_Set &handlers)
  {
    HASH_MAP_ITER end_iter = this->cache_map_.end ();

    for (HASH_MAP_ITER iter = this->cache_map_.begin ();
         iter != end_iter;
         ++iter)
      {
        // Get the transport to fill its associated connection's handler.
        (*iter).int_id_.transport ()->provide_handler (handlers);

        // Inform the transport that has a reference to the entry in the
        // map that we are *gone* now. So, the transport should not use
        // the reference to the entry that he has, to access us *at any
        // time*.
        (*iter).int_id_.transport ()->cache_map_entry (0);
      }

    // Unbind all the entries in the map
    this->cache_map_.unbind_all ();

    return 0;
  }

  template <typename TT, typename TRDT, typename PSTRAT>
  bool
  Transport_Cache_Manager_T<TT, TRDT, PSTRAT>::blockable_client_transports_i (
    Connection_Handler_Set &h)
  {
    HASH_MAP_ITER end_iter = this->cache_map_.end ();

    for (HASH_MAP_ITER iter = this->cache_map_.begin ();
         iter != end_iter;
         ++iter)
      {
        // Get the transport to fill its associated connection's
        // handler.
        bool const retval =
          (*iter).int_id_.transport ()->provide_blockable_handler (h);

        // Do not mark the entry as closed if we don't have a
        // blockable handler added
        if (retval)
          (*iter).int_id_.recycle_state (ENTRY_CLOSED);
      }

    return true;
  }

  template <typename TT, typename TRDT, typename PSTRAT>
  int
  Transport_Cache_Manager_T<TT, TRDT, PSTRAT>::purge_entry_i (HASH_MAP_ENTRY *&entry)
  {
    int retval = 0;

    if (entry != 0)
      {
        // Remove the entry from the Map
        retval = this->cache_map_.unbind (entry);

        // Set the entry pointer to zero
        entry = 0;

#if defined (TAO_HAS_MONITOR_POINTS) && (TAO_HAS_MONITOR_POINTS == 1)
        this->size_monitor_->receive (this->current_size ());
#endif /* TAO_HAS_MONITOR_POINTS==1 */
      }

    return retval;
  }

  template <typename TT, typename TRDT, typename PSTRAT>
  void
  Transport_Cache_Manager_T<TT, TRDT, PSTRAT>::mark_invalid_i (HASH_MAP_ENTRY *entry)
  {
    if (entry != 0)
      {
        // Mark the entry as not usable
        entry->item ().recycle_state (ENTRY_PURGABLE_BUT_NOT_IDLE);
      }
  }

  template <typename TT, typename TRDT, typename PSTRAT>
  bool
  Transport_Cache_Manager_T<TT, TRDT, PSTRAT>::is_entry_available_i (const HASH_MAP_ENTRY &entry)
  {
    Cache_Entries_State entry_state = entry.int_id_.recycle_state ();
    bool result = (entry_state == ENTRY_IDLE_AND_PURGABLE);

    if (result && entry.int_id_.transport () != 0)
    {
      // if it's not connected, it's not available
      result = entry.int_id_.is_connected ();
    }

    if (TAO_debug_level > 8)
      {
        ACE_DEBUG ((LM_DEBUG,
                    ACE_TEXT ("TAO (%P|%t) - Transport_Cache_Manager_T::")
                    ACE_TEXT ("is_entry_available_i[%d], %C state is %C\n"),
                    entry.int_id_.transport () ? entry.int_id_.transport ()->id () : 0,
                    (result ? "true" : "false"),
                    Cache_IntId::state_name (entry_state)));
      }

    return result;
  }

  template <typename TT, typename TRDT, typename PSTRAT>
  bool
  Transport_Cache_Manager_T<TT, TRDT, PSTRAT>::is_entry_purgable_i (HASH_MAP_ENTRY &entry)
  {
    Cache_Entries_State entry_state = entry.int_id_.recycle_state ();
    transport_type* transport = entry.int_id_.transport ();
    bool result = (entry_state == ENTRY_IDLE_AND_PURGABLE ||
                   entry_state == ENTRY_PURGABLE_BUT_NOT_IDLE)
                   && transport->can_be_purged ();

    if (TAO_debug_level > 8)
      {
        ACE_DEBUG ((LM_DEBUG,
                    ACE_TEXT ("TAO (%P|%t) - Transport_Cache_Manager_T::")
                    ACE_TEXT ("is_entry_purgable_i[%d], %C state is %C\n"),
                    entry.int_id_.transport ()->id (),
                    (result ? "true" : "false"),
                    Cache_IntId::state_name (entry_state)));
      }

    return result;
  }

  template <typename TT, typename TRDT, typename PSTRAT>
  bool
  Transport_Cache_Manager_T<TT, TRDT, PSTRAT>::
    is_entry_connecting_i (const HASH_MAP_ENTRY &entry)
  {
    Cache_Entries_State entry_state = entry.int_id_.recycle_state ();
    bool result = (entry_state == ENTRY_CONNECTING);

    if (!result && entry.int_id_.transport () != 0)
      {
        // if we're not connected, that counts, too.
        // Can this happen?  Not sure <wilsond@ociweb.com>
        result = !entry.int_id_.is_connected ();
      }

    if (TAO_debug_level > 8)
      {
        ACE_DEBUG ((LM_DEBUG,
                    ACE_TEXT ("TAO (%P|%t) - Transport_Cache_Manager_T::")
                    ACE_TEXT ("is_entry_connecting_i[%d], %C, state is %C\n"),
                    entry.int_id_.transport () ? entry.int_id_.transport ()->id () : 0,
                    (result ? "true" : "false"),
                    Cache_IntId::state_name (entry_state)));
      }

    return result;
  }

#if !defined (ACE_LACKS_QSORT)
  template <typename TT, typename TRDT, typename PSTRAT>
  int
  Transport_Cache_Manager_T<TT, TRDT, PSTRAT>::
    cpscmp(const void* a, const void* b)
  {
    const HASH_MAP_ENTRY** left  = (const HASH_MAP_ENTRY**)a;
    const HASH_MAP_ENTRY** right = (const HASH_MAP_ENTRY**)b;

    if ((*left)->int_id_.transport ()->purging_order () <
        (*right)->int_id_.transport ()->purging_order ())
      return -1;

    if ((*left)->int_id_.transport ()->purging_order () >
        (*right)->int_id_.transport ()->purging_order ())
      return 1;

    return 0;
  }
#endif /* ACE_LACKS_QSORT */

  template <typename TT, typename TRDT, typename PSTRAT>
  int
  Transport_Cache_Manager_T<TT, TRDT, PSTRAT>::purge (void)
  {
    typedef ACE_Unbounded_Set<transport_type*> transport_set_type;
    transport_set_type transports_to_be_closed;

    {
      ACE_MT (ACE_GUARD_RETURN (ACE_Lock, ace_mon, *this->cache_lock_, 0));

      DESCRIPTOR_SET sorted_set = 0;
      int const sorted_size = this->fill_set_i (sorted_set);

      // Only call close_entries () if sorted_set != 0.  It takes
      // control of sorted_set and cleans up any allocated memory.  If
      // sorted_set == 0, then there is nothing to de-allocate.
      if (sorted_set != 0)
        {
          // BEGIN FORMER close_entries
          // Calculate the number of entries to purge, when we have
          // to purge try to at least to purge minimal of 1 entry
          // which is needed if we have a very small cache maximum
          int const amount = (sorted_size * this->percent_) / 100;

          if (TAO_debug_level > 4)
            {
              ACE_DEBUG ((LM_INFO,
                ACE_TEXT ("TAO (%P|%t) - Transport_Cache_Manager_T::purge, ")
                ACE_TEXT ("Trying to purge %d of %d cache entries\n"),
                amount,
                sorted_size));
            }

          int count = 0;

          for (int i = 0; count < amount && i < sorted_size; ++i)
            {
              if (this->is_entry_purgable_i (*sorted_set[i]))
                {
                  transport_type* transport =
                    sorted_set[i]->int_id_.transport ();
                  sorted_set[i]->int_id_.recycle_state (ENTRY_BUSY);
                  transport->add_reference ();

                  if (TAO_debug_level > 4)
                    {
                      ACE_DEBUG ((LM_INFO,
                        ACE_TEXT ("TAO (%P|%t) - Transport_Cache_Manager_T::purge, ")
                        ACE_TEXT ("Purgable Transport[%d] found in ")
                        ACE_TEXT ("cache\n"),
                        transport->id ()));
                    }

                  if (transports_to_be_closed.insert_tail (transport) != 0)
                    {
                      if (TAO_debug_level > 0)
                        {
                          ACE_ERROR ((LM_ERROR,
                            ACE_TEXT ("TAO (%P|%t) - Transport_Cache_Manager_T")
                            ACE_TEXT ("::purge, Unable to add transport[%d] ")
                            ACE_TEXT ("on the to-be-closed set, so ")
                            ACE_TEXT ("it will not be purged\n"),
                            transport->id ()));
                        }
                      transport->remove_reference ();
                    }

                  // Count this as a successful purged entry
                  ++count;
                }
            }

          delete [] sorted_set;
          sorted_set = 0;
          // END FORMER close_entries
        }
    }

    // Now, without the lock held, lets go through and close all the transports.
    if (! transports_to_be_closed.is_empty ())
      {
        typename transport_set_type::iterator it (transports_to_be_closed);
        while (! it.done ())
          {
            transport_type *transport = *it;

            it.advance ();

            if (transport)
              {
                transport->close_connection ();
                transport->remove_reference ();
              }
          }
      }

    if (TAO_debug_level > 4)
      {
        ACE_DEBUG ((LM_INFO,
          ACE_TEXT ("TAO (%P|%t) - Transport_Cache_Manager_T::purge, ")
          ACE_TEXT ("Cache size after purging is [%d]\n"),
          this->current_size ()
          ));
      }

#if defined (TAO_HAS_MONITOR_POINTS) && (TAO_HAS_MONITOR_POINTS == 1)
    /// The value doesn't matter, all we need is the timestamp,
    /// which is added automatically.
    this->purge_monitor_->receive (static_cast<size_t> (0UL));
    /// And update the size monitor as well.
    this->size_monitor_->receive (this->current_size ());
#endif /* TAO_HAS_MONITOR_POINTS==1 */

    return 0;
  }

  template <typename TT, typename TRDT, typename PSTRAT>
  void
  Transport_Cache_Manager_T<TT, TRDT, PSTRAT>::
    sort_set (DESCRIPTOR_SET& entries, int current_size)
  {
#if defined (ACE_LACKS_QSORT)
    // Use insertion sort if we don't have qsort
    for(int i = 1; i < current_size; ++i)
      {
        if (entries[i]->int_id_.transport ()->purging_order () <
            entries[i - 1]->int_id_.transport ()->purging_order ())
          {
            HASH_MAP_ENTRY* entry = entries[i];

            for(int j = i; j > 0 &&
                  entries[j - 1]->int_id_.transport ()->purging_order () >
                  entry->item ().transport ()->purging_order (); --j)
              {
                HASH_MAP_ENTRY* holder = entries[j];
                entries[j] = entries[j - 1];
                entries[j - 1] = holder;
              }
          }
      }
#else
    ACE_OS::qsort (entries, current_size,
                   sizeof (HASH_MAP_ENTRY*), (ACE_COMPARE_FUNC)cpscmp);
#endif /* ACE_LACKS_QSORT */
  }

  template <typename TT, typename TRDT, typename PSTRAT>
  int
  Transport_Cache_Manager_T<TT, TRDT, PSTRAT>::
    fill_set_i (DESCRIPTOR_SET& sorted_set)
  {
    int current_size = 0;
    int const cache_maximum = this->purging_strategy_->cache_maximum ();

    // set sorted_set to 0.  This signifies nothing to purge.
    sorted_set = 0;

    // Do we need to worry about cache purging?
    if (cache_maximum >= 0)
      {
        current_size = static_cast<int> (this->current_size ());

        if (TAO_debug_level > 6)
          {
            ACE_DEBUG ((LM_DEBUG,
              ACE_TEXT ("TAO (%P|%t) - Transport_Cache_Manager_T::fill_set_i, ")
              ACE_TEXT ("current_size = %d, cache_maximum = %d\n"),
              current_size, cache_maximum));
          }

        if (current_size >= cache_maximum)
          {
            ACE_NEW_RETURN (sorted_set, HASH_MAP_ENTRY*[current_size], 0);

            HASH_MAP_ITER iter = this->cache_map_.begin ();

            for (int i = 0; i < current_size; ++i)
              {
                sorted_set[i] = &(*iter);
                ++iter;
              }

            this->sort_set (sorted_set, current_size);
          }
      }

    return current_size;
  }
}

TAO_END_VERSIONED_NAMESPACE_DECL