ACE/ace/Countdown_Time_T.h

   1 // -*- C++ -*-
   2
   3 //=============================================================================
   4 /**
   5  *  @file    Countdown_Time_T.h
   6  *
   7  *  @author Douglas C. Schmidt <d.schmidt@vanderbilt.edu>
   8  */
   9 //=============================================================================
  10
  11 #ifndef ACE_COUNTDOWN_TIME_T_H
  12 #define ACE_COUNTDOWN_TIME_T_H
  13
  14 #include /**/ "ace/pre.h"
  15
  16 #include /**/ "ace/ACE_export.h"
  17
  18 #if !defined (ACE_LACKS_PRAGMA_ONCE)
  19 # pragma once
  20 #endif /* ACE_LACKS_PRAGMA_ONCE */
  21
  22 #include "ace/Time_Value.h"
  23 #include "ace/Time_Policy.h"
  24 #include "ace/Copy_Disabled.h"
  25
  26 ACE_BEGIN_VERSIONED_NAMESPACE_DECL
  27
  28 /**
  29  * @class ACE_Countdown_Time
  30  *
  31  * @brief Keeps track of the amount of elapsed time.
  32  *
  33  * This class has a side-effect on the @c max_wait_time -- every
  34  * time the stop() method is called the @c max_wait_time is
  35  * updated.
  36  */
  37 template <typename TIME_POLICY = ACE_Default_Time_Policy>
  38 class ACE_Countdown_Time_T : private ACE_Copy_Disabled
  39 {
  40 public:
  41   /// Cache the @a max_wait_time and call @c start().
  42   ACE_Countdown_Time_T (ACE_Time_Value *max_wait_time,
  43                         TIME_POLICY const & time_policy = TIME_POLICY());
  44
  45   /// Destructor, makes sure the max_wait_time that got passed as pointer
  46   /// to the constructor is updated with the time elapsed.
  47   ~ACE_Countdown_Time_T ();
  48
  49   /// Cache the current time and enter a start state.
  50   void start ();
  51
  52   /// Subtract the elapsed time from max_wait_time_ and enter a stopped
  53   /// state.
  54   void stop ();
  55
  56   /// Calls stop and then start.  max_wait_time_ is modified by the
  57   /// call to stop.
  58   void update ();
  59
  60   /// Returns true if we've already been stopped, else false.
  61   bool stopped () const;
  62
  63   /// Allows applications to control how the timer queue gets the time
  64   /// of day.
  65   void set_time_policy(TIME_POLICY const & time_policy);
  66
  67 private:
  68   /// The policy to return the current time of day
  69   TIME_POLICY time_policy_;
  70
  71   /// Maximum time we are monitoring
  72   ACE_Time_Value *max_wait_time_;
  73
  74   /// Copy of the maximum time value, used to avoid nested decrements
  75   ACE_Time_Value max_wait_value_;
  76
  77   /// Beginning of the start time.
  78   ACE_Time_Value start_time_;
  79
  80   /// Keeps track of whether we've already been stopped.
  81   bool stopped_;
  82 };
  83
  84 ACE_END_VERSIONED_NAMESPACE_DECL
  85
  86 #include /**/ "ace/post.h"
  87
  88 #if defined (__ACE_INLINE__)
  89 #include "ace/Countdown_Time_T.inl"
  90 #endif /* __ACE_INLINE__ */
  91
  92 #include "ace/Countdown_Time_T.cpp"
  93
  94 #endif /* ACE_COUNTDOWN_TIME_T_H */