TAO/tao/LF_Strategy.h

   1 // -*- C++ -*-
   2
   3 //=============================================================================
   4 /**
   5  *  @file LF_Strategy.h
   6  *
   7  *  @author Carlos O'Ryan <coryan@uci.edu>
   8  */
   9 //=============================================================================
  10
  11 #ifndef TAO_LF_STRATEGY_H
  12 #define TAO_LF_STRATEGY_H
  13
  14 #include /**/ "ace/pre.h"
  15
  16 #include /**/ "tao/TAO_Export.h"
  17
  18 #if !defined (ACE_LACKS_PRAGMA_ONCE)
  19 # pragma once
  20 #endif /* ACE_LACKS_PRAGMA_ONCE */
  21
  22 #include /**/ "tao/Versioned_Namespace.h"
  23
  24 ACE_BEGIN_VERSIONED_NAMESPACE_DECL
  25 class ACE_Time_Value;
  26 ACE_END_VERSIONED_NAMESPACE_DECL
  27
  28 TAO_BEGIN_VERSIONED_NAMESPACE_DECL
  29
  30 class TAO_Leader_Follower;
  31
  32 /**
  33  * @brief Strategize Leader/Follower manipulations in the ORB event
  34  * loop.
  35  *
  36  * The ORB event loop must participate in the Leader/Followers
  37  * protocol, but only if that concurrency model is configured,
  38  * otherwise performance suffers.
  39  *
  40  * This class strategizes the ORB behavior in this respect.
  41  */
  42 class TAO_Export TAO_LF_Strategy
  43 {
  44 public:
  45   /// Destructor
  46   virtual ~TAO_LF_Strategy ();
  47
  48   /// The current thread will handle an upcall
  49   /**
  50    * Threads that handle requests can block for long periods of time,
  51    * causing deadlocks if they don't elect a new leader before
  52    * starting the upcall the system can become non-responsive or
  53    * dead-lock.
  54    */
  55   virtual void set_upcall_thread (TAO_Leader_Follower &) = 0;
  56
  57   /// The current thread is entering the reactor event loop
  58   /**
  59    * Threads that block in the reactor event loop become "server"
  60    * threads for the Leader/Follower set.  They must be flagged
  61    * specially because they do not wait for one specific event, but
  62    * for any event whatsoever.
  63    */
  64   virtual int set_event_loop_thread (ACE_Time_Value *max_wait_time,
  65                                      TAO_Leader_Follower &) = 0;
  66
  67   /// The current thread is leaving the event loop
  68   /**
  69    * When the thread leaves the event loop a new leader must be
  70    * elected.
  71    */
  72   virtual void reset_event_loop_thread (int call_reset,
  73                                         TAO_Leader_Follower &) = 0;
  74 };
  75
  76 TAO_END_VERSIONED_NAMESPACE_DECL
  77
  78 #include /**/ "ace/post.h"
  79
  80 #endif  /* TAO_LF_STRATEGY_H */