ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK > Class Template Reference

Provides an interface to timers. More...

#include <Timer_Queue_T.h>

Collaboration diagram for ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >:

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List of all members.

Public Types

typedef
ACE_Timer_Queue_Iterator_T
< TYPE, FUNCTOR, ACE_LOCK > 
ITERATOR
 Type of Iterator.

Public Member Functions

 ACE_Timer_Queue_T (FUNCTOR *upcall_functor=0, ACE_Free_List< ACE_Timer_Node_T< TYPE > > *freelist=0)
virtual ~ACE_Timer_Queue_T (void)
virtual bool is_empty (void) const =0
 True if queue is empty, else false.
virtual const ACE_Time_Valueearliest_time (void) const =0
virtual long schedule (const TYPE &type, const void *act, const ACE_Time_Value &future_time, const ACE_Time_Value &interval=ACE_Time_Value::zero)
virtual int reset_interval (long timer_id, const ACE_Time_Value &interval)=0
virtual int cancel (const TYPE &type, int dont_call_handle_close=1)=0
virtual int cancel (long timer_id, const void **act=0, int dont_call_handle_close=1)=0
virtual int expire (const ACE_Time_Value &current_time)
virtual int dispatch_info (const ACE_Time_Value &current_time, ACE_Timer_Node_Dispatch_Info_T< TYPE > &info)
int expire (void)
ACE_Time_Value gettimeofday (void)
void gettimeofday (ACE_Time_Value(*gettimeofday)(void))
virtual ACE_Time_Valuecalculate_timeout (ACE_Time_Value *max)
virtual ACE_Time_Valuecalculate_timeout (ACE_Time_Value *max, ACE_Time_Value *the_timeout)
void timer_skew (const ACE_Time_Value &skew)
 Set the timer skew for the Timer_Queue.
const ACE_Time_Valuetimer_skew (void) const
 Get the timer skew for the Timer_Queue.
ACE_LOCK & mutex (void)
 Synchronization variable used by the queue.
FUNCTOR & upcall_functor (void)
 Accessor to the upcall functor.
virtual ITERATORiter (void)=0
 Returns a pointer to this ACE_Timer_Queue's iterator.
virtual ACE_Timer_Node_T< TYPE > * remove_first (void)=0
 Removes the earliest node from the queue and returns it.
virtual void dump (void) const
 Dump the state of a object.
virtual ACE_Timer_Node_T< TYPE > * get_first (void)=0
 Reads the earliest node from the queue and returns it.
virtual void return_node (ACE_Timer_Node_T< TYPE > *)
void preinvoke (ACE_Timer_Node_Dispatch_Info_T< TYPE > &info, const ACE_Time_Value &cur_time, const void *&upcall_act)
 This method will call the preinvoke() on <functor>.
void upcall (ACE_Timer_Node_Dispatch_Info_T< TYPE > &info, const ACE_Time_Value &cur_time)
 This method will call the timeout() on <functor>.
void postinvoke (ACE_Timer_Node_Dispatch_Info_T< TYPE > &info, const ACE_Time_Value &cur_time, const void *upcall_act)
 This method will call the postinvoke() on <functor>.

Protected Member Functions

virtual long schedule_i (const TYPE &type, const void *act, const ACE_Time_Value &future_time, const ACE_Time_Value &interval)=0
 Schedule a timer.
virtual void reschedule (ACE_Timer_Node_T< TYPE > *)=0
 Reschedule an "interval" ACE_Timer_Node.
virtual ACE_Timer_Node_T< TYPE > * alloc_node (void)
 Factory method that allocates a new node.
virtual void free_node (ACE_Timer_Node_T< TYPE > *)
 Factory method that frees a previously allocated node.
virtual int dispatch_info_i (const ACE_Time_Value &current_time, ACE_Timer_Node_Dispatch_Info_T< TYPE > &info)
 Non-locking version of dispatch_info ().

Protected Attributes

ACE_LOCK mutex_
ACE_Free_List
< ACE_Timer_Node_T< TYPE > > * 
free_list_
 Class that implements a free list.
ACE_Time_Value(* gettimeofday_ )(void)
 Pointer to function that returns the current time of day.
FUNCTOR * upcall_functor_
 Upcall functor.
bool const delete_upcall_functor_
 To delete or not to delete is the question?
bool const delete_free_list_
 Flag to delete only if the class created the <free_list_>.

Private Member Functions

 ACE_Timer_Queue_T (const ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK > &)
void operator= (const ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK > &)

Private Attributes

ACE_Time_Value timeout_
 Returned by <calculate_timeout>.
ACE_Time_Value timer_skew_
 Adjusts for timer skew in various clocks.


Detailed Description

template<class TYPE, class FUNCTOR, class ACE_LOCK>
class ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >

Provides an interface to timers.

This is an abstract base class that provides hook for implementing specialized policies such as ACE_Timer_List and ACE_Timer_Heap.


Member Typedef Documentation

template<class TYPE, class FUNCTOR, class ACE_LOCK>
typedef ACE_Timer_Queue_Iterator_T<TYPE, FUNCTOR, ACE_LOCK> ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::ITERATOR

Type of Iterator.


Constructor & Destructor Documentation

template<class TYPE, class FUNCTOR, class ACE_LOCK>
ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::ACE_Timer_Queue_T ( FUNCTOR *  upcall_functor = 0,
ACE_Free_List< ACE_Timer_Node_T< TYPE > > *  freelist = 0 
)

Default constructor. upcall_functor is the instance of the FUNCTOR to be used by the queue. If upcall_functor is 0, Timer Queue will create a default FUNCTOR. freelist the freelist of timer nodes. If 0, then a default freelist will be created.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
virtual ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::~ACE_Timer_Queue_T ( void   )  [virtual]

Destructor - make virtual for proper destruction of inherited classes.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::ACE_Timer_Queue_T ( const ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK > &   )  [private]


Member Function Documentation

template<class TYPE, class FUNCTOR, class ACE_LOCK>
virtual ACE_Timer_Node_T<TYPE>* ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::alloc_node ( void   )  [protected, virtual]

Factory method that allocates a new node.

Reimplemented in ACE_Timer_Heap_T< TYPE, FUNCTOR, ACE_LOCK >.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
virtual ACE_Time_Value* ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::calculate_timeout ( ACE_Time_Value max,
ACE_Time_Value the_timeout 
) [virtual]

Determine the next event to timeout. Returns max if there are no pending timers or if all pending timers are longer than max. <the_timeout> should be a pointer to storage for the timeout value, and this value is also returned. This method does not acquire a lock internally since it doesn't modify internal state. If you need to call this method when the queue is being modified concurrently, however, you should make sure to acquire the <mutex()> externally before making the call.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
virtual ACE_Time_Value* ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::calculate_timeout ( ACE_Time_Value max  )  [virtual]

Determine the next event to timeout. Returns max if there are no pending timers or if all pending timers are longer than max. This method acquires a lock internally since it modifies internal state.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
virtual int ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::cancel ( long  timer_id,
const void **  act = 0,
int  dont_call_handle_close = 1 
) [pure virtual]

Cancel the single timer that matches the timer_id value (which was returned from the <schedule> method). If act is non-NULL then it will be set to point to the ``magic cookie'' argument passed in when the timer was registered. This makes it possible to free up the memory and avoid memory leaks. If dont_call_handle_close is 0 then the <functor> will be invoked, which typically calls the <handle_close> hook. Returns 1 if cancellation succeeded and 0 if the timer_id wasn't found.

Implemented in ACE_Timer_Hash_T< TYPE, FUNCTOR, ACE_LOCK, BUCKET >, ACE_Timer_Heap_T< TYPE, FUNCTOR, ACE_LOCK >, ACE_Timer_List_T< TYPE, FUNCTOR, ACE_LOCK >, and ACE_Timer_Wheel_T< TYPE, FUNCTOR, ACE_LOCK >.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
virtual int ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::cancel ( const TYPE &  type,
int  dont_call_handle_close = 1 
) [pure virtual]

Cancel all timer associated with type. If dont_call_handle_close is 0 then the <functor> will be invoked, which typically invokes the <handle_close> hook. Returns number of timers cancelled.

Implemented in ACE_Timer_Hash_T< TYPE, FUNCTOR, ACE_LOCK, BUCKET >, ACE_Timer_Heap_T< TYPE, FUNCTOR, ACE_LOCK >, ACE_Timer_List_T< TYPE, FUNCTOR, ACE_LOCK >, and ACE_Timer_Wheel_T< TYPE, FUNCTOR, ACE_LOCK >.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
virtual int ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::dispatch_info ( const ACE_Time_Value current_time,
ACE_Timer_Node_Dispatch_Info_T< TYPE > &  info 
) [virtual]

Get the dispatch information for a timer whose value is <= current_time. This does not account for <timer_skew>. Returns 1 if there is a node whose value <= current_time else returns a 0.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
virtual int ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::dispatch_info_i ( const ACE_Time_Value current_time,
ACE_Timer_Node_Dispatch_Info_T< TYPE > &  info 
) [protected, virtual]

Non-locking version of dispatch_info ().

Reimplemented in ACE_Timer_Hash_T< TYPE, FUNCTOR, ACE_LOCK, BUCKET >.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
virtual void ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::dump ( void   )  const [virtual]

template<class TYPE, class FUNCTOR, class ACE_LOCK>
virtual const ACE_Time_Value& ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::earliest_time ( void   )  const [pure virtual]

Returns the time of the earlier node in the Timer_Queue. Must be called on a non-empty queue.

Implemented in ACE_Timer_Hash_T< TYPE, FUNCTOR, ACE_LOCK, BUCKET >, ACE_Timer_Heap_T< TYPE, FUNCTOR, ACE_LOCK >, ACE_Timer_List_T< TYPE, FUNCTOR, ACE_LOCK >, and ACE_Timer_Wheel_T< TYPE, FUNCTOR, ACE_LOCK >.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
int ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::expire ( void   ) 

Run the <functor> for all timers whose values are <= <ACE_OS::gettimeofday>. Also accounts for <timer_skew>.

Depending on the resolution of the underlying OS the system calls like select()/poll() might return at time different than that is specified in the timeout. Suppose the OS guarantees a resolution of t ms. The timeline will look like

A B | | V V |-------------|-------------|-------------|-------------| t t t t t

If you specify a timeout value of A, then the timeout will not occur at A but at the next interval of the timer, which is later than that is expected. Similarly, if your timeout value is equal to B, then the timeout will occur at interval after B. Now depending upon the resolution of your timeouts and the accuracy of the timeouts needed for your application, you should set the value of <timer_skew>. In the above case, if you want the timeout A to fire no later than A, then you should specify your <timer_skew> to be A % t.

The timeout value should be specified via the macro ACE_TIMER_SKEW in your config.h file. The default value is zero.

Things get interesting if the t before the timeout value B is zero i.e your timeout is less than the interval. In that case, you are almost sure of not getting the desired timeout behaviour. Maybe you should look for a better OS :-)

Returns the number of timers canceled.

Reimplemented in ACE_Timer_Hash_T< TYPE, FUNCTOR, ACE_LOCK, BUCKET >, and ACE_Timer_Wheel_T< TYPE, FUNCTOR, ACE_LOCK >.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
virtual int ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::expire ( const ACE_Time_Value current_time  )  [virtual]

Run the <functor> for all timers whose values are <= current_time. This does not account for <timer_skew>. Returns the number of timers canceled.

Reimplemented in ACE_Timer_Hash_T< TYPE, FUNCTOR, ACE_LOCK, BUCKET >, and ACE_Timer_Wheel_T< TYPE, FUNCTOR, ACE_LOCK >.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
virtual void ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::free_node ( ACE_Timer_Node_T< TYPE > *   )  [protected, virtual]

Factory method that frees a previously allocated node.

Reimplemented in ACE_Timer_Hash_T< TYPE, FUNCTOR, ACE_LOCK, BUCKET >, and ACE_Timer_Heap_T< TYPE, FUNCTOR, ACE_LOCK >.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
virtual ACE_Timer_Node_T<TYPE>* ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::get_first ( void   )  [pure virtual]

template<class TYPE, class FUNCTOR, class ACE_LOCK>
void ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::gettimeofday ( ACE_Time_Value(*)(void)  gettimeofday  ) 

Allows applications to control how the timer queue gets the time of day.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
ACE_Time_Value ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::gettimeofday ( void   ) 

Returns the current time of day. This method allows different implementations of the timer queue to use special high resolution timers.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
virtual bool ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::is_empty ( void   )  const [pure virtual]

template<class TYPE, class FUNCTOR, class ACE_LOCK>
virtual ITERATOR& ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::iter ( void   )  [pure virtual]

template<class TYPE, class FUNCTOR, class ACE_LOCK>
ACE_LOCK& ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::mutex ( void   ) 

Synchronization variable used by the queue.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
void ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::operator= ( const ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK > &   )  [private]

template<class TYPE, class FUNCTOR, class ACE_LOCK>
void ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::postinvoke ( ACE_Timer_Node_Dispatch_Info_T< TYPE > &  info,
const ACE_Time_Value cur_time,
const void *  upcall_act 
)

This method will call the postinvoke() on <functor>.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
void ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::preinvoke ( ACE_Timer_Node_Dispatch_Info_T< TYPE > &  info,
const ACE_Time_Value cur_time,
const void *&  upcall_act 
)

This method will call the preinvoke() on <functor>.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
virtual ACE_Timer_Node_T<TYPE>* ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::remove_first ( void   )  [pure virtual]

template<class TYPE, class FUNCTOR, class ACE_LOCK>
virtual void ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::reschedule ( ACE_Timer_Node_T< TYPE > *   )  [protected, pure virtual]

template<class TYPE, class FUNCTOR, class ACE_LOCK>
virtual int ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::reset_interval ( long  timer_id,
const ACE_Time_Value interval 
) [pure virtual]

Resets the interval of the timer represented by timer_id to interval, which is specified in relative time to the current <gettimeofday>. If interval is equal to ACE_Time_Value::zero, the timer will become a non-rescheduling timer. Returns 0 if successful, -1 if not.

Implemented in ACE_Timer_Hash_T< TYPE, FUNCTOR, ACE_LOCK, BUCKET >, ACE_Timer_Heap_T< TYPE, FUNCTOR, ACE_LOCK >, ACE_Timer_List_T< TYPE, FUNCTOR, ACE_LOCK >, and ACE_Timer_Wheel_T< TYPE, FUNCTOR, ACE_LOCK >.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
virtual void ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::return_node ( ACE_Timer_Node_T< TYPE > *   )  [virtual]

Method used to return a timer node to the queue's ownership after it is returned by a method like <remove_first>.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
virtual long ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::schedule ( const TYPE &  type,
const void *  act,
const ACE_Time_Value future_time,
const ACE_Time_Value interval = ACE_Time_Value::zero 
) [virtual]

Schedule type that will expire at future_time, which is specified in absolute time. If it expires then act is passed in as the value to the <functor>. If interval is != to ACE_Time_Value::zero then it is used to reschedule the type automatically, using relative time to the current <gettimeofday>. This method returns a <timer_id> that uniquely identifies the the type entry in an internal list. This <timer_id> can be used to cancel the timer before it expires. The cancellation ensures that <timer_ids> are unique up to values of greater than 2 billion timers. As long as timers don't stay around longer than this there should be no problems with accidentally deleting the wrong timer. Returns -1 on failure (which is guaranteed never to be a valid <timer_id>).

template<class TYPE, class FUNCTOR, class ACE_LOCK>
virtual long ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::schedule_i ( const TYPE &  type,
const void *  act,
const ACE_Time_Value future_time,
const ACE_Time_Value interval 
) [protected, pure virtual]

template<class TYPE, class FUNCTOR, class ACE_LOCK>
const ACE_Time_Value& ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::timer_skew ( void   )  const

Get the timer skew for the Timer_Queue.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
void ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::timer_skew ( const ACE_Time_Value skew  ) 

Set the timer skew for the Timer_Queue.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
void ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::upcall ( ACE_Timer_Node_Dispatch_Info_T< TYPE > &  info,
const ACE_Time_Value cur_time 
)

This method will call the timeout() on <functor>.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
FUNCTOR& ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::upcall_functor ( void   ) 

Accessor to the upcall functor.


Member Data Documentation

template<class TYPE, class FUNCTOR, class ACE_LOCK>
bool const ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::delete_free_list_ [protected]

Flag to delete only if the class created the <free_list_>.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
bool const ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::delete_upcall_functor_ [protected]

To delete or not to delete is the question?

template<class TYPE, class FUNCTOR, class ACE_LOCK>
ACE_Free_List<ACE_Timer_Node_T<TYPE> >* ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::free_list_ [protected]

Class that implements a free list.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
ACE_Time_Value(* ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::gettimeofday_)(void) [protected]

Pointer to function that returns the current time of day.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
ACE_LOCK ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::mutex_ [protected]

Synchronization variable for ACE_Timer_Queue.

Note:
The right name would be lock_, but HP/C++ will choke on that!

template<class TYPE, class FUNCTOR, class ACE_LOCK>
ACE_Time_Value ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::timeout_ [private]

Returned by <calculate_timeout>.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
ACE_Time_Value ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::timer_skew_ [private]

Adjusts for timer skew in various clocks.

template<class TYPE, class FUNCTOR, class ACE_LOCK>
FUNCTOR* ACE_Timer_Queue_T< TYPE, FUNCTOR, ACE_LOCK >::upcall_functor_ [protected]

Upcall functor.


The documentation for this class was generated from the following file:

Generated on Tue Apr 14 11:13:17 2009 for ACE by  doxygen 1.5.8