TAO/tao/CSD_ThreadPool/CSD_TP_Synch_Helper.h

   1 // -*- C++ -*-
   2
   3 //=============================================================================
   4 /**
   5  *  @file    CSD_TP_Synch_Helper.h
   6  *
   7  *  @author  Tim Bradley <bradley_t@ociweb.com>
   8  */
   9 //=============================================================================
  10
  11 #ifndef TAO_CSD_TP_SYNCH_HELPER_H
  12 #define TAO_CSD_TP_SYNCH_HELPER_H
  13
  14 #include /**/ "ace/pre.h"
  15
  16 #include "tao/CSD_ThreadPool/CSD_TP_Export.h"
  17 #include "tao/Condition.h"
  18
  19 #if !defined (ACE_LACKS_PRAGMA_ONCE)
  20 # pragma once
  21 #endif /* ACE_LACKS_PRAGMA_ONCE */
  22
  23 #include "ace/Synch.h"
  24
  25 TAO_BEGIN_VERSIONED_NAMESPACE_DECL
  26
  27 namespace TAO
  28 {
  29   namespace CSD
  30   {
  31     /**
  32      * @class TP_Synch_Helper
  33      *
  34      * @brief Helper class for synchronous requests to block the requesting
  35      *        thread until the appropriate time (when it will be un-blocked).
  36      *
  37      * TBD - Description here
  38      *
  39      */
  40     class TAO_CSD_TP_Export TP_Synch_Helper
  41     {
  42     public:
  43       /// Constructor.  Sets initial state to PENDING.
  44       TP_Synch_Helper();
  45
  46       /// Destructor.
  47       ~TP_Synch_Helper();
  48
  49       /// Returns true if the helper state is DISPATCHED, and false if
  50       /// the helper state is CANCELLED.  However, if the helper state
  51       /// is PENDING, then this method will block the calling thread
  52       /// until the state changes to something other than PENDING
  53       /// (ie, DISPATCHED or CANCELLED).
  54       bool wait_while_pending();
  55
  56       /// Change the state of this helper to DISPATCHED, which will cause
  57       /// wait_while_pending() to unblock.
  58       void dispatched();
  59
  60       /// Change the state of this helper to CANCELLED, which will cause
  61       /// wait_while_pending() to unblock.
  62       void cancelled();
  63
  64     private:
  65       /// Enumeration Type for all possible states of this helper object.
  66       enum HelperState
  67       {
  68         PENDING,
  69         DISPATCHED,
  70         CANCELLED
  71       };
  72
  73       /// Thread lock type
  74       typedef TAO_SYNCH_MUTEX LockType;
  75
  76       /// Thread condition type
  77       typedef TAO_Condition<LockType> ConditionType;
  78
  79       /// Lock used to protect the state and condition.
  80       LockType lock_;
  81
  82       /// Used to denote the state of the request dispatching.
  83       HelperState state_;
  84
  85       /// The condition used to block the calling thread until the
  86       /// state is something other than the PENDING state.
  87       ConditionType condition_;
  88     };
  89   }
  90 }
  91
  92 TAO_END_VERSIONED_NAMESPACE_DECL
  93
  94 #if defined (__ACE_INLINE__)
  95 # include "tao/CSD_ThreadPool/CSD_TP_Synch_Helper.inl"
  96 #endif /* __ACE_INLINE__ */
  97
  98 #include /**/ "ace/post.h"
  99
 100 #endif /* TAO_CSD_TP_SYNCH_HELPER_H */