ACE/ace/Priority_Reactor.h

   1 // -*- C++ -*-
   2
   3 //=============================================================================
   4 /**
   5  *  @file    Priority_Reactor.h
   6  *
   7  *  @author Carlos O'Ryan <coryan@uci.edu>
   8  */
   9 //=============================================================================
  10
  11 #ifndef ACE_PRIORITY_REACTOR_H
  12 #define ACE_PRIORITY_REACTOR_H
  13 #include /**/ "ace/pre.h"
  14
  15 #include /**/ "ace/ACE_export.h"
  16
  17 #if !defined (ACE_LACKS_PRAGMA_ONCE)
  18 # pragma once
  19 #endif /* ACE_LACKS_PRAGMA_ONCE */
  20
  21 #include "ace/Select_Reactor.h"
  22 #include "ace/Unbounded_Queue.h"
  23
  24 ACE_BEGIN_VERSIONED_NAMESPACE_DECL
  25
  26 /**
  27  * @class ACE_Priority_Reactor
  28  *
  29  * @brief Implements priority based dispatching.
  30  *
  31  * This class refines the dispatching mechanism for the
  32  * Select_Reactor by taking advantage of the priority method on
  33  * ACE_Event_Handler.
  34  */
  35 class ACE_Export ACE_Priority_Reactor : public ACE_Select_Reactor
  36 {
  37 public:
  38   /// Initialize ACE_Priority_Reactor with the default size.
  39   ACE_Priority_Reactor (ACE_Sig_Handler * = 0,
  40                         ACE_Timer_Queue * = 0);
  41
  42   /// Initialize ACE_Priority_Reactor with size @a size.
  43   ACE_Priority_Reactor (size_t size,
  44                         bool restart = false,
  45                         ACE_Sig_Handler * = 0,
  46                         ACE_Timer_Queue * = 0);
  47
  48   /// Close down the select_reactor and release all of its resources.
  49   virtual ~ACE_Priority_Reactor ();
  50
  51   /// Dump the state of an object.
  52   void dump () const;
  53
  54   /// Declare the dynamic allocation hooks.
  55   ACE_ALLOC_HOOK_DECLARE;
  56
  57 protected:
  58   // = Dispatching methods.
  59
  60   /// We simply override this function to implement the priority
  61   /// dispatching.
  62   virtual int dispatch_io_set (int number_of_active_handles,
  63                                int &number_dispatched,
  64                                int mask,
  65                                ACE_Handle_Set &dispatch_mask,
  66                                ACE_Handle_Set &ready_mask,
  67                                ACE_EH_PTMF callback);
  68
  69 private:
  70   /// A small helper to initialize the bucket.
  71   void init_bucket ();
  72
  73   /// Build the bucket from the given dispatch_mask.  Return -1 on
  74   /// failure, 0 otherwise.
  75   int build_bucket (ACE_Handle_Set& dispatch_mask,
  76                      int &min_priority,
  77                      int &max_priority);
  78
  79   /// There is a queue per-priority, which simply holds the
  80   /// Event_Handlers until we know who goes first.
  81   typedef ACE_Unbounded_Queue<ACE_Event_Tuple> QUEUE;
  82   QUEUE** bucket_;
  83
  84   /// The queues themselves use this allocator to minimize dynamic
  85   /// memory usage.
  86   ACE_Allocator* tuple_allocator_;
  87
  88   /// Deny access since member-wise won't work...
  89   ACE_Priority_Reactor (const ACE_Priority_Reactor &);
  90   ACE_Priority_Reactor &operator = (const ACE_Priority_Reactor &);
  91 };
  92
  93 ACE_END_VERSIONED_NAMESPACE_DECL
  94
  95 #include /**/ "ace/post.h"
  96 #endif /* ACE_PRIORITY_REACTOR_H */