TAO/tao/LF_Multi_Event.h

   1 // -*- C++ -*-
   2
   3 //=============================================================================
   4 /**
   5  *  @file LF_Multi_Event.h
   6  *
   7  *  @author Phil Mesnier <mesnier_p@ociweb.com>
   8  */
   9 //=============================================================================
  10
  11 #ifndef TAO_LF_MULTI_EVENT_H
  12 #define TAO_LF_MULTI_EVENT_H
  13
  14 #include /**/ "ace/pre.h"
  15
  16 #include "tao/LF_Event.h"
  17
  18 #if !defined (ACE_LACKS_PRAGMA_ONCE)
  19 # pragma once
  20 #endif /* ACE_LACKS_PRAGMA_ONCE */
  21
  22 TAO_BEGIN_VERSIONED_NAMESPACE_DECL
  23
  24 // Forward decls
  25 class TAO_Connection_Handler;
  26 class TAO_Transport;
  27
  28 /**
  29  * @class TAO_LF_Multi_Event
  30  *
  31  * @brief Use the Leader/Follower loop to wait for one specific event
  32  * in the invocation path.
  33  *
  34  * Used by the parallel connection strategy for waiting on one of many
  35  * connections.
  36  */
  37 class TAO_Export TAO_LF_Multi_Event: public TAO_LF_Event
  38 {
  39 public:
  40   /// Constructor
  41   TAO_LF_Multi_Event (void);
  42
  43   /// Destructor
  44   virtual ~TAO_LF_Multi_Event (void);
  45
  46   /// Propagate the follower to all the events in the collection.
  47   virtual int bind (TAO_LF_Follower *follower);
  48
  49   /// Unbind the follower from all the collected events.
  50   virtual int unbind (TAO_LF_Follower *follower);
  51
  52   /// Adds a handler to the collection
  53   void add_event (TAO_Connection_Handler *ch);
  54
  55   /// Returns the connection handler that caused the successful status
  56   /// to be returned.
  57   TAO_Connection_Handler *winner(void);
  58
  59   /// Returns the transport associated with the first entry in the collection.
  60   TAO_Transport *base_transport(void);
  61
  62 private:
  63   void operator= (const TAO_LF_Multi_Event &);
  64   TAO_LF_Multi_Event (const TAO_LF_Multi_Event &);
  65
  66 protected:
  67   /// Validate the state change
  68   virtual void state_changed_i (LFS_STATE new_state);
  69
  70   /// Check whether we have reached the final state..
  71   virtual bool is_state_final () const;
  72
  73   /// Return true if the condition was satisfied successfully, false if it
  74   /// has not - This iterates over the list of attached events and
  75   /// returns true if any of them return true from successful.
  76   virtual bool successful_i () const;
  77
  78   /// Return true if an error was detected while waiting for the
  79   /// event - This iterates over the list of events and returns
  80   /// true only if all of them return true from error_detected().
  81   virtual bool error_detected_i () const;
  82
  83 private:
  84
  85   struct Event_Node {
  86     TAO_Connection_Handler * ptr_;
  87     Event_Node *next_;
  88   };
  89
  90   struct Event_Node *events_;
  91
  92   mutable TAO_Connection_Handler * winner_;
  93 };
  94
  95 TAO_END_VERSIONED_NAMESPACE_DECL
  96
  97 #include /**/ "ace/post.h"
  98
  99 #endif  /* TAO_LF_Multi_EVENT_H */