ACE_Notification_Queue Class Reference

Implements a user-space queue to send Reactor notifications. More...

#include <Notification_Queue.h>

Inheritance diagram for ACE_Notification_Queue:

Collaboration diagram for ACE_Notification_Queue:

List of all members.

Public Member Functions
	ACE_Notification_Queue ()
	~ACE_Notification_Queue ()
int	open ()
	Pre-allocate resources in the queue.
void	reset ()
	Release all resources in the queue.
int	purge_pending_notifications (ACE_Event_Handler *eh, ACE_Reactor_Mask mask)
	Remove all elements in the queue matching eh and mask.
int	push_new_notification (ACE_Notification_Buffer const &buffer)
	Add a new notification to the queue.
int	pop_next_notification (ACE_Notification_Buffer &current, bool &more_messages_queued, ACE_Notification_Buffer &next)
	Extract the next notification from the queue.
Private Types
typedef ACE_Intrusive_List < ACE_Notification_Queue_Node >	Buffer_List
Private Member Functions
int	allocate_more_buffers ()
	Allocate more memory for the queue.
Private Attributes
ACE_Unbounded_Queue < ACE_Notification_Queue_Node * >	alloc_queue_
Buffer_List	notify_queue_
	Keeps track of all pending notifications.
Buffer_List	free_queue_
	Keeps track of all free buffers.
ACE_SYNCH_MUTEX	notify_queue_lock_
	Synchronization for handling of queues.

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Detailed Description

Implements a user-space queue to send Reactor notifications.

The ACE_Reactor uses a pipe to send wake up the thread running the event loop from other threads. This pipe can be limited in size under some operating systems. For some applications, this limit presents a problem. A user-space notification queue is used to overcome those limitations. The queue tries to use as few resources on the pipe as possible, while keeping all the data in user space.

This code was refactored from Select_Reactor_Base.

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Member Typedef Documentation

typedef ACE_Intrusive_List<ACE_Notification_Queue_Node> ACE_Notification_Queue::Buffer_List [private]

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Constructor & Destructor Documentation

ACE_Notification_Queue::ACE_Notification_Queue

(

)

ACE_Notification_Queue::~ACE_Notification_Queue

(

)

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Member Function Documentation

int ACE_Notification_Queue::allocate_more_buffers

(

)

[private]

Allocate more memory for the queue.

int ACE_Notification_Queue::open

(

void

)

Pre-allocate resources in the queue.

int ACE_Notification_Queue::pop_next_notification	(	ACE_Notification_Buffer &	current,
		bool &	more_messages_queued,
		ACE_Notification_Buffer &	next
	)

Extract the next notification from the queue.

Returns:

-1 on failure, 1 if a message was popped, 0 otherwise

int ACE_Notification_Queue::purge_pending_notifications	(	ACE_Event_Handler *	eh,
		ACE_Reactor_Mask	mask
	)

Remove all elements in the queue matching eh and mask.

I suggest reading the documentation in ACE_Reactor to find a more detailed description. This is just a helper function.

int ACE_Notification_Queue::push_new_notification

(

ACE_Notification_Buffer const &

buffer

)

Add a new notification to the queue.

Returns:

-1 on failure, 1 if a new message should be sent through the pipe and 0 otherwise.

void ACE_Notification_Queue::reset

(

)

Release all resources in the queue.

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Member Data Documentation

ACE_Unbounded_Queue<ACE_Notification_Queue_Node*> ACE_Notification_Queue::alloc_queue_ [private]

Keeps track of allocated arrays of type ACE_Notification_Buffer. The idea is to amortize allocation costs by allocating multiple ACE_Notification_Buffer objects at a time.

Buffer_List ACE_Notification_Queue::free_queue_ [private]

Keeps track of all free buffers.

Buffer_List ACE_Notification_Queue::notify_queue_ [private]

Keeps track of all pending notifications.

ACE_SYNCH_MUTEX ACE_Notification_Queue::notify_queue_lock_ [private]

Synchronization for handling of queues.

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

• Notification_Queue.h
• Notification_Queue.cpp