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ACE_Message_Queue Class Template Reference

A threaded message queueing facility, modeled after the queueing facilities in System V STREAMs. More...

#include <Message_Queue_T.h>

Inheritance diagram for ACE_Message_Queue:

[legend]Collaboration diagram for ACE_Message_Queue:

Public Types
typedef ACE_Message_Queue_Iterator< ACE_SYNCH_USE >	ITERATOR
typedef ACE_Message_Queue_Reverse_Iterator< ACE_SYNCH_USE >	REVERSE_ITERATOR
Public Methods
	ACE_Message_Queue (size_t high_water_mark=ACE_Message_Queue_Base::DEFAULT_HWM, size_t low_water_mark=ACE_Message_Queue_Base::DEFAULT_LWM, ACE_Notification_Strategy *=0)
virtual int	open (size_t hwm=ACE_Message_Queue_Base::DEFAULT_HWM, size_t lwm=ACE_Message_Queue_Base::DEFAULT_LWM, ACE_Notification_Strategy *=0)
virtual int	close (void)
	Release all resources from the message queue and mark it as deactivated. Returns the number of messages released from the queue. More...
virtual	~ACE_Message_Queue (void)
	Release all resources from the message queue and mark it as deactivated. More...
virtual int	flush (void)
	Release all resources from the message queue but do not mark it as deactivated. More...
virtual int	flush_i (void)
	Release all resources from the message queue but do not mark it as deactivated. More...
virtual int	peek_dequeue_head (ACE_Message_Block &first_item, ACE_Time_Value timeout=0)
virtual int	enqueue_prio (ACE_Message_Block new_item, ACE_Time_Value timeout=0)
virtual int	enqueue_deadline (ACE_Message_Block new_item, ACE_Time_Value timeout=0)
virtual int	enqueue (ACE_Message_Block new_item, ACE_Time_Value timeout=0)
virtual int	enqueue_tail (ACE_Message_Block new_item, ACE_Time_Value timeout=0)
virtual int	enqueue_head (ACE_Message_Block new_item, ACE_Time_Value timeout=0)
virtual int	dequeue (ACE_Message_Block &first_item, ACE_Time_Value timeout=0)
	This method is an alias for the following <dequeue_head> method. More...
virtual int	dequeue_head (ACE_Message_Block &first_item, ACE_Time_Value timeout=0)
virtual int	dequeue_prio (ACE_Message_Block &first_item, ACE_Time_Value timeout=0)
virtual int	dequeue_tail (ACE_Message_Block &dequeued, ACE_Time_Value timeout=0)
virtual int	dequeue_deadline (ACE_Message_Block &dequeued, ACE_Time_Value timeout=0)
virtual int	is_full (void)
	True if queue is full, else false. More...
virtual int	is_empty (void)
	True if queue is empty, else false. More...
virtual size_t	message_bytes (void)
virtual size_t	message_length (void)
virtual int	message_count (void)
virtual void	message_bytes (size_t new_size)
virtual void	message_length (size_t new_length)
virtual size_t	high_water_mark (void)
virtual void	high_water_mark (size_t hwm)
virtual size_t	low_water_mark (void)
virtual void	low_water_mark (size_t lwm)
virtual int	deactivate (void)
virtual int	activate (void)
virtual int	pulse (void)
virtual int	state (void)
	Returns the current state of the queue, which can be one of ACTIVATED, DEACTIVATED, or PULSED. More...
virtual int	deactivated (void)
	Returns true if the state of the queue is <DEACTIVATED>, but false if the queue's is <ACTIVATED> or <PULSED>. More...
virtual int	notify (void)
virtual ACE_Notification_Strategy *	notification_strategy (void)
	Get the notification strategy for the <Message_Queue>. More...
virtual void	notification_strategy (ACE_Notification_Strategy *s)
	Set the notification strategy for the <Message_Queue>. More...
virtual ACE_SYNCH_MUTEX_T &	lock (void)
	Returns a reference to the lock used by the <ACE_Message_Queue>. More...
virtual void	dump (void) const
	Dump the state of an object. More...
Public Attributes
	ACE_ALLOC_HOOK_DECLARE
	Declare the dynamic allocation hooks. More...
Protected Methods
virtual int	enqueue_i (ACE_Message_Block *new_item)
	Enqueue an <ACE_Message_Block > in accordance with its priority.* More...
virtual int	enqueue_deadline_i (ACE_Message_Block *new_item)
	Enqueue an <ACE_Message_Block > in accordance with its deadline time.* More...
virtual int	enqueue_tail_i (ACE_Message_Block *new_item)
	Enqueue an <ACE_Message_Block > at the end of the queue.* More...
virtual int	enqueue_head_i (ACE_Message_Block *new_item)
	Enqueue an <ACE_Message_Block > at the head of the queue.* More...
virtual int	dequeue_head_i (ACE_Message_Block *&first_item)
	Dequeue and return the <ACE_Message_Block > at the head of the queue.* More...
virtual int	dequeue_prio_i (ACE_Message_Block *&dequeued)
	Dequeue and return the <ACE_Message_Block > with the lowest priority.* More...
virtual int	dequeue_tail_i (ACE_Message_Block *&first_item)
	Dequeue and return the <ACE_Message_Block > at the tail of the queue.* More...
virtual int	dequeue_deadline_i (ACE_Message_Block *&first_item)
	Dequeue and return the <ACE_Message_Block > with the lowest deadline time.* More...
virtual int	is_full_i (void)
	True if queue is full, else false. More...
virtual int	is_empty_i (void)
	True if queue is empty, else false. More...
virtual int	deactivate_i (int pulse=0)
virtual int	activate_i (void)
	Activate the queue. More...
virtual int	wait_not_full_cond (ACE_Guard< ACE_SYNCH_MUTEX_T > &mon, ACE_Time_Value *timeout)
	Wait for the queue to become non-full. More...
virtual int	wait_not_empty_cond (ACE_Guard< ACE_SYNCH_MUTEX_T > &mon, ACE_Time_Value *timeout)
	Wait for the queue to become non-empty. More...
virtual int	signal_enqueue_waiters (void)
	Inform any threads waiting to enqueue that they can procede. More...
virtual int	signal_dequeue_waiters (void)
	Inform any threads waiting to dequeue that they can procede. More...
Protected Attributes
ACE_Message_Block *	head_
	Pointer to head of ACE_Message_Block list. More...
ACE_Message_Block *	tail_
	Pointer to tail of ACE_Message_Block list. More...
size_t	low_water_mark_
	Lowest number before unblocking occurs. More...
size_t	high_water_mark_
	Greatest number of bytes before blocking. More...
size_t	cur_bytes_
	Current number of bytes in the queue. More...
size_t	cur_length_
	Current length of messages in the queue. More...
int	cur_count_
	Current number of messages in the queue. More...
ACE_Notification_Strategy *	notification_strategy_
	The notification strategy used when a new message is enqueued. More...
ACE_SYNCH_MUTEX_T	lock_
	Protect queue from concurrent access. More...
ACE_SYNCH_CONDITION_T	not_empty_cond_
	Used to make threads sleep until the queue is no longer empty. More...
ACE_SYNCH_CONDITION_T	not_full_cond_
	Used to make threads sleep until the queue is no longer full. More...
Private Methods
void	operator= (const ACE_Message_Queue< _ACE_SYNCH > &)
	ACE_Message_Queue (const ACE_Message_Queue< _ACE_SYNCH > &)
Friends
class	ACE_Message_Queue_Iterator< ACE_SYNCH_USE >
class	ACE_Message_Queue_Reverse_Iterator< ACE_SYNCH_USE >

Detailed Description

template<ACE_SYNCH_DECL>
class ACE_Message_Queue<>

A threaded message queueing facility, modeled after the queueing facilities in System V STREAMs.

An <ACE_Message_Queue> is the central queueing facility for messages in the ACE framework. If <ACE_SYNCH_DECL> is <ACE_MT_SYNCH> then all operations are thread-safe. Otherwise, if it's <ACE_NULL_SYNCH> then there's no locking overhead.

Definition at line 45 of file Message_Queue_T.h.

Member Typedef Documentation

template<ACE_SYNCH_DECL >

typedef ACE_Message_Queue_Iterator<ACE_SYNCH_USE> ACE_Message_Queue::ITERATOR

Definition at line 53 of file Message_Queue_T.h.

template<ACE_SYNCH_DECL >

typedef ACE_Message_Queue_Reverse_Iterator<ACE_SYNCH_USE> ACE_Message_Queue::REVERSE_ITERATOR

Definition at line 55 of file Message_Queue_T.h.

Constructor & Destructor Documentation

template<ACE_SYNCH_DECL >

ACE_Message_Queue<>::ACE_Message_Queue ( size_t high_water_mark = ACE_Message_Queue_Base::DEFAULT_HWM,

size_t low_water_mark = ACE_Message_Queue_Base::DEFAULT_LWM,

ACE_Notification_Strategy * = 0

)

Initialize an <ACE_Message_Queue>. The <high_water_mark> determines how many bytes can be stored in a queue before it's considered "full." Supplier threads must block until the queue is no longer full. The <low_water_mark> determines how many bytes must be in the queue before supplier threads are allowed to enqueue additional <ACE_Message_Block>s. By default, the <high_water_mark> equals the <low_water_mark>, which means that suppliers will be able to enqueue new messages as soon as a consumer removes any message from the queue. Making the <low_water_mark> smaller than the <high_water_mark> forces consumers to drain more messages from the queue before suppliers can enqueue new messages, which can minimize the "silly window syndrome."

template<ACE_SYNCH_DECL >

virtual ACE_Message_Queue<>::~ACE_Message_Queue ( void ) [virtual]

Release all resources from the message queue and mark it as deactivated.

template<ACE_SYNCH_DECL >

ACE_Message_Queue<>::ACE_Message_Queue ( const ACE_Message_Queue< _ACE_SYNCH > & ) [private]

Member Function Documentation

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::activate ( void ) [virtual]

Reactivate the queue so that threads can enqueue and dequeue messages again. Returns the state of the queue before the call.
Implements ACE_Message_Queue_Base.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::activate_i ( void ) [protected, virtual]

Activate the queue.

Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::activate.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::close ( void ) [virtual]

Release all resources from the message queue and mark it as deactivated. Returns the number of messages released from the queue.

Implements ACE_Message_Queue_Base.
Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::~ACE_Message_Queue.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::deactivate ( void ) [virtual]

Deactivate the queue and wakeup all threads waiting on the queue so they can continue. No messages are removed from the queue, however. Any other operations called until the queue is activated again will immediately return -1 with <errno> == ESHUTDOWN. Returns WAS_INACTIVE if queue was inactive before the call and WAS_ACTIVE if queue was active before the call.
Implements ACE_Message_Queue_Base.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::deactivate_i ( int pulse = 0 ) [protected, virtual]

Notifies all waiting threads that the queue has been deactivated so they can wakeup and continue other processing. No messages are removed from the queue.
Parameters:

pulse If 0, the queue's state is changed to DEACTIVATED and any other operations called until the queue is reactivated will immediately return -1 with errno == ESHUTDOWN. If not zero, only the waiting threads are notified and the queue's state changes to PULSED.

Returns:
The state of the queue before the call.

Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::close, ACE_Message_Queue< ACE_SYNCH_USE >::deactivate, and ACE_Message_Queue< ACE_SYNCH_USE >::pulse.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::deactivated ( void ) [virtual]

Returns true if the state of the queue is <DEACTIVATED>, but false if the queue's is <ACTIVATED> or <PULSED>.

Implements ACE_Message_Queue_Base.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::dequeue ( ACE_Message_Block *& first_item,

ACE_Time_Value * timeout = 0

) [virtual]

This method is an alias for the following <dequeue_head> method.

Implements ACE_Message_Queue_Base.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::dequeue_deadline ( ACE_Message_Block *& dequeued,

ACE_Time_Value * timeout = 0

) [virtual]

Dequeue and return the <ACE_Message_Block *> with the lowest deadlien time. Note that <timeout> uses <{absolute}> time rather than <{relative}> time. If the <timeout> elapses without receiving a message -1 is returned and <errno> is set to <EWOULDBLOCK>. If the queue is deactivated -1 is returned and <errno> is set to <ESHUTDOWN>. Otherwise, returns -1 on failure, else the number of items still on the queue.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::dequeue_deadline_i ( ACE_Message_Block *& first_item ) [protected, virtual]

Dequeue and return the <ACE_Message_Block *> with the lowest deadline time.

Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::dequeue_deadline.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::dequeue_head ( ACE_Message_Block *& first_item,

ACE_Time_Value * timeout = 0

) [virtual]

Dequeue and return the <ACE_Message_Block *> at the head of the queue. Note that <timeout> uses <{absolute}> time rather than <{relative}> time. If the <timeout> elapses without receiving a message -1 is returned and <errno> is set to <EWOULDBLOCK>. If the queue is deactivated -1 is returned and <errno> is set to <ESHUTDOWN>. Otherwise, returns -1 on failure, else the number of items still on the queue.
Implements ACE_Message_Queue_Base.
Reimplemented in ACE_Dynamic_Message_Queue.
Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::dequeue, and ACE_WFMO_Reactor_Notify::purge_pending_notifications.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::dequeue_head_i ( ACE_Message_Block *& first_item ) [protected, virtual]

Dequeue and return the <ACE_Message_Block *> at the head of the queue.

Reimplemented in ACE_Dynamic_Message_Queue.
Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::dequeue_deadline_i, and ACE_Message_Queue< ACE_SYNCH_USE >::dequeue_head.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::dequeue_prio ( ACE_Message_Block *& first_item,

ACE_Time_Value * timeout = 0

) [virtual]

Dequeue and return the <ACE_Message_Block *> that has the lowest priority. Note that <timeout> uses <{absolute}> time rather than <{relative}> time. If the <timeout> elapses without receiving a message -1 is returned and <errno> is set to <EWOULDBLOCK>. If the queue is deactivated -1 is returned and <errno> is set to <ESHUTDOWN>. Otherwise, returns -1 on failure, else the number of items still on the queue.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::dequeue_prio_i ( ACE_Message_Block *& dequeued ) [protected, virtual]

Dequeue and return the <ACE_Message_Block *> with the lowest priority.

Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::dequeue_prio.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::dequeue_tail ( ACE_Message_Block *& dequeued,

ACE_Time_Value * timeout = 0

) [virtual]

Dequeue and return the <ACE_Message_Block *> at the tail of the queue. Note that <timeout> uses <{absolute}> time rather than <{relative}> time. If the <timeout> elapses without receiving a message -1 is returned and <errno> is set to <EWOULDBLOCK>. If the queue is deactivated -1 is returned and <errno> is set to <ESHUTDOWN>. Otherwise, returns -1 on failure, else the number of items still on the queue.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::dequeue_tail_i ( ACE_Message_Block *& first_item ) [protected, virtual]

Dequeue and return the <ACE_Message_Block *> at the tail of the queue.

Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::dequeue_tail.

template<ACE_SYNCH_DECL >

virtual void ACE_Message_Queue<>::dump ( void ) const [virtual]

Dump the state of an object.

Implements ACE_Message_Queue_Base.
Reimplemented in ACE_Dynamic_Message_Queue.
Referenced by ACE_Dynamic_Message_Queue::dump.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::enqueue ( ACE_Message_Block * new_item,

ACE_Time_Value * timeout = 0

) [virtual]

This is an alias for <enqueue_prio>. It's only here for backwards compatibility and will go away in a subsequent release. Please use <enqueue_prio> instead. Note that <timeout> uses <{absolute}> time rather than <{relative}> time.
Implements ACE_Message_Queue_Base.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::enqueue_deadline ( ACE_Message_Block * new_item,

ACE_Time_Value * timeout = 0

) [virtual]

Enqueue an <ACE_Message_Block *> into the <Message_Queue> in accordance with its <msg_deadline_time>. FIFO order is maintained when messages of the same deadline time are inserted consecutively. Note that <timeout> uses <{absolute}> time rather than <{relative}> time. If the <timeout> elapses without receiving a message -1 is returned and <errno> is set to <EWOULDBLOCK>. If the queue is deactivated -1 is returned and <errno> is set to <ESHUTDOWN>. Otherwise, returns -1 on failure, else the number of items still on the queue.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::enqueue_deadline_i ( ACE_Message_Block * new_item ) [protected, virtual]

Enqueue an <ACE_Message_Block *> in accordance with its deadline time.

Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::enqueue_deadline.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::enqueue_head ( ACE_Message_Block * new_item,

ACE_Time_Value * timeout = 0

) [virtual]

Enqueue an <ACE_Message_Block *> at the head of the queue. Note that <timeout> uses <{absolute}> time rather than <{relative}> time. If the <timeout> elapses without receiving a message -1 is returned and <errno> is set to <EWOULDBLOCK>. If the queue is deactivated -1 is returned and <errno> is set to <ESHUTDOWN>. Otherwise, returns -1 on failure, else the number of items still on the queue.
Reimplemented in ACE_Dynamic_Message_Queue.
Referenced by ACE_WFMO_Reactor_Notify::purge_pending_notifications.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::enqueue_head_i ( ACE_Message_Block * new_item ) [protected, virtual]

Enqueue an <ACE_Message_Block *> at the head of the queue.

Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::enqueue_deadline_i, ACE_Message_Queue< ACE_SYNCH_USE >::enqueue_head, and ACE_Message_Queue< ACE_SYNCH_USE >::enqueue_i.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::enqueue_i ( ACE_Message_Block * new_item ) [protected, virtual]

Enqueue an <ACE_Message_Block *> in accordance with its priority.

Reimplemented in ACE_Dynamic_Message_Queue.
Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::enqueue_prio.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::enqueue_prio ( ACE_Message_Block * new_item,

ACE_Time_Value * timeout = 0

) [virtual]

Enqueue an ACE_Message_Block into the queue in accordance with the ACE_Message_Block's priority (0 is lowest priority). FIFO order is maintained when messages of the same priority are inserted consecutively.
Parameters:

new_item Pointer to an ACE_Message_Block that will be added to the queue. The block's msg_priority() method will be called to obtain the queueing priority.

timeout The absolute time the caller will wait until for the block to be queued.

Return values:

>0 The number of ACE_Message_Blocks on the queue after adding the specified block.

-1 On failure. errno holds the reason. If EWOULDBLOCK, the timeout elapsed. If ESHUTDOWN, the queue was deactivated or pulsed.

Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::enqueue.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::enqueue_tail ( ACE_Message_Block * new_item,

ACE_Time_Value * timeout = 0

) [virtual]

Enqueue an <ACE_Message_Block *> at the end of the queue. Note that <timeout> uses <{absolute}> time rather than <{relative}> time. If the <timeout> elapses without receiving a message -1 is returned and <errno> is set to <EWOULDBLOCK>. If the queue is deactivated -1 is returned and <errno> is set to <ESHUTDOWN>. Otherwise, returns -1 on failure, else the number of items still on the queue.
Implements ACE_Message_Queue_Base.
Reimplemented in ACE_Dynamic_Message_Queue.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::enqueue_tail_i ( ACE_Message_Block * new_item ) [protected, virtual]

Enqueue an <ACE_Message_Block *> at the end of the queue.

Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::enqueue_deadline_i, ACE_Message_Queue< ACE_SYNCH_USE >::enqueue_i, and ACE_Message_Queue< ACE_SYNCH_USE >::enqueue_tail.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::flush ( void ) [virtual]

Release all resources from the message queue but do not mark it as deactivated.
This method holds the queue lock during this operation.

Returns:
The number of messages flushed.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::flush_i ( void ) [virtual]

Release all resources from the message queue but do not mark it as deactivated.
The caller must be holding the queue lock before calling this method.

Returns:
The number of messages flushed.

Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::close, and ACE_Message_Queue< ACE_SYNCH_USE >::flush.

template<ACE_SYNCH_DECL >

virtual void ACE_Message_Queue<>::high_water_mark ( size_t hwm ) [virtual]

Set the high watermark, which determines how many bytes can be stored in a queue before it's considered "full."

template<ACE_SYNCH_DECL >

virtual size_t ACE_Message_Queue<>::high_water_mark ( void ) [virtual]

Get high watermark.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::is_empty ( void ) [virtual]

True if queue is empty, else false.

Implements ACE_Message_Queue_Base.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::is_empty_i ( void ) [protected, virtual]

True if queue is empty, else false.

Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::is_empty.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::is_full ( void ) [virtual]

True if queue is full, else false.

Implements ACE_Message_Queue_Base.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::is_full_i ( void ) [protected, virtual]

True if queue is full, else false.

Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::is_full.

template<ACE_SYNCH_DECL >

virtual ACE_SYNCH_MUTEX_T& ACE_Message_Queue<>::lock ( void ) [inline, virtual]

Returns a reference to the lock used by the <ACE_Message_Queue>.

Definition at line 384 of file Message_Queue_T.h.

00385 { 00386 // The Sun Forte 6 (CC 5.1) compiler is only happy if this is in the 00387 // header file (j.russell.noseworthy@objectsciences.com) 00388 return this->lock_; 00389 }

template<ACE_SYNCH_DECL >

virtual void ACE_Message_Queue<>::low_water_mark ( size_t lwm ) [virtual]

Set the low watermark, which determines how many bytes must be in the queue before supplier threads are allowed to enqueue additional <ACE_Message_Block>s.

template<ACE_SYNCH_DECL >

virtual size_t ACE_Message_Queue<>::low_water_mark ( void ) [virtual]

Get low watermark.

template<ACE_SYNCH_DECL >

virtual void ACE_Message_Queue<>::message_bytes ( size_t new_size ) [virtual]

New value of the number of total bytes on the queue, i.e., sum of the message block sizes.
Implements ACE_Message_Queue_Base.

template<ACE_SYNCH_DECL >

virtual size_t ACE_Message_Queue<>::message_bytes ( void ) [virtual]

Number of total bytes on the queue, i.e., sum of the message block sizes.
Implements ACE_Message_Queue_Base.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::message_count ( void ) [virtual]

Number of total messages on the queue.
Implements ACE_Message_Queue_Base.
Referenced by ACE_WFMO_Reactor_Notify::purge_pending_notifications.

template<ACE_SYNCH_DECL >

virtual void ACE_Message_Queue<>::message_length ( size_t new_length ) [virtual]

New value of the number of total length on the queue, i.e., sum of the message block lengths.
Implements ACE_Message_Queue_Base.

template<ACE_SYNCH_DECL >

virtual size_t ACE_Message_Queue<>::message_length ( void ) [virtual]

Number of total length on the queue, i.e., sum of the message block lengths.
Implements ACE_Message_Queue_Base.

template<ACE_SYNCH_DECL >

virtual void ACE_Message_Queue<>::notification_strategy ( ACE_Notification_Strategy * s ) [virtual]

Set the notification strategy for the <Message_Queue>.

Implements ACE_Message_Queue_Base.

template<ACE_SYNCH_DECL >

virtual ACE_Notification_Strategy* ACE_Message_Queue<>::notification_strategy ( void ) [virtual]

Get the notification strategy for the <Message_Queue>.

Implements ACE_Message_Queue_Base.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::notify ( void ) [virtual]

This hook is automatically invoked by <enqueue_head>, <enqueue_tail>, and <enqueue_prio> when a new item is inserted into the queue. Subclasses can override this method to perform specific notification strategies (e.g., signaling events for a <WFMO_Reactor>, notifying a <Reactor>, etc.). In a multi-threaded application with concurrent consumers, there is no guarantee that the queue will be still be non-empty by the time the notification occurs.
Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::enqueue_deadline, ACE_Message_Queue< ACE_SYNCH_USE >::enqueue_head, ACE_Message_Queue< ACE_SYNCH_USE >::enqueue_prio, and ACE_Message_Queue< ACE_SYNCH_USE >::enqueue_tail.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::open ( size_t hwm = ACE_Message_Queue_Base::DEFAULT_HWM,

size_t lwm = ACE_Message_Queue_Base::DEFAULT_LWM,

ACE_Notification_Strategy * = 0

) [virtual]

Initialize an <ACE_Message_Queue>. The <high_water_mark> determines how many bytes can be stored in a queue before it's considered "full." Supplier threads must block until the queue is no longer full. The <low_water_mark> determines how many bytes must be in the queue before supplier threads are allowed to enqueue additional <ACE_Message_Block>s. By default, the <high_water_mark> equals the <low_water_mark>, which means that suppliers will be able to enqueue new messages as soon as a consumer removes any message from the queue. Making the <low_water_mark> smaller than the <high_water_mark> forces consumers to drain more messages from the queue before suppliers can enqueue new messages, which can minimize the "silly window syndrome."
Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::ACE_Message_Queue.

template<ACE_SYNCH_DECL >

void ACE_Message_Queue<>::operator= ( const ACE_Message_Queue< _ACE_SYNCH > & ) [private]

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::peek_dequeue_head ( ACE_Message_Block *& first_item,

ACE_Time_Value * timeout = 0

) [virtual]

Retrieve a pointer to the first ACE_Message_Block in the queue without removing it.
Parameters:

first_item Reference to an ACE_Message_Block * that will point to the first block on the queue. The block remains on the queue until this or another thread dequeues it.

timeout The absolute time the caller will wait until for a block to be queued.

Return values:

>0 The number of ACE_Message_Blocks on the queue.

-1 On failure. errno holds the reason. If EWOULDBLOCK, the timeout elapsed. If ESHUTDOWN, the queue was deactivated or pulsed.

Implements ACE_Message_Queue_Base.
Reimplemented in ACE_Dynamic_Message_Queue.
Referenced by ACE_Dynamic_Message_Queue::peek_dequeue_head.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::pulse ( void ) [virtual]

Pulse the queue to wake up any waiting threads. Changes the queue state to PULSED; future enqueue/dequeue operations proceed as in ACTIVATED state.

Returns:
The queue's state before this call.

Implements ACE_Message_Queue_Base.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::signal_dequeue_waiters ( void ) [protected, virtual]

Inform any threads waiting to dequeue that they can procede.

Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::enqueue_deadline_i, ACE_Message_Queue< ACE_SYNCH_USE >::enqueue_head_i, ACE_Message_Queue< ACE_SYNCH_USE >::enqueue_i, and ACE_Message_Queue< ACE_SYNCH_USE >::enqueue_tail_i.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::signal_enqueue_waiters ( void ) [protected, virtual]

Inform any threads waiting to enqueue that they can procede.

Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::dequeue_deadline_i, ACE_Message_Queue< ACE_SYNCH_USE >::dequeue_head_i, ACE_Message_Queue< ACE_SYNCH_USE >::dequeue_prio_i, and ACE_Message_Queue< ACE_SYNCH_USE >::dequeue_tail_i.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::state ( void ) [virtual]

Returns the current state of the queue, which can be one of ACTIVATED, DEACTIVATED, or PULSED.

Reimplemented from ACE_Message_Queue_Base.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::wait_not_empty_cond ( ACE_Guard< ACE_SYNCH_MUTEX_T > & mon,

ACE_Time_Value * timeout

) [protected, virtual]

Wait for the queue to become non-empty.

Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::dequeue_deadline, ACE_Message_Queue< ACE_SYNCH_USE >::dequeue_head, ACE_Message_Queue< ACE_SYNCH_USE >::dequeue_prio, ACE_Message_Queue< ACE_SYNCH_USE >::dequeue_tail, and ACE_Message_Queue< ACE_SYNCH_USE >::peek_dequeue_head.

template<ACE_SYNCH_DECL >

virtual int ACE_Message_Queue<>::wait_not_full_cond ( ACE_Guard< ACE_SYNCH_MUTEX_T > & mon,

ACE_Time_Value * timeout

) [protected, virtual]

Wait for the queue to become non-full.

Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::enqueue_deadline, ACE_Message_Queue< ACE_SYNCH_USE >::enqueue_head, ACE_Message_Queue< ACE_SYNCH_USE >::enqueue_prio, and ACE_Message_Queue< ACE_SYNCH_USE >::enqueue_tail.

Friends And Related Function Documentation

template<ACE_SYNCH_DECL >

friend class ACE_Message_Queue_Iterator< ACE_SYNCH_USE > [friend]

Definition at line 48 of file Message_Queue_T.h.

template<ACE_SYNCH_DECL >

friend class ACE_Message_Queue_Reverse_Iterator< ACE_SYNCH_USE > [friend]

Definition at line 49 of file Message_Queue_T.h.

Member Data Documentation

template<ACE_SYNCH_DECL >

ACE_Message_Queue::ACE_ALLOC_HOOK_DECLARE

Declare the dynamic allocation hooks.

Reimplemented from ACE_Message_Queue_Base.
Reimplemented in ACE_Dynamic_Message_Queue.
Definition at line 395 of file Message_Queue_T.h.

template<ACE_SYNCH_DECL >

size_t ACE_Message_Queue::cur_length_ [protected]

Current length of messages in the queue.

Definition at line 495 of file Message_Queue_T.h.
Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::dequeue_deadline_i, ACE_Message_Queue< ACE_SYNCH_USE >::dequeue_head_i, ACE_Message_Queue< ACE_SYNCH_USE >::dequeue_prio_i, ACE_Message_Queue< ACE_SYNCH_USE >::dequeue_tail_i, ACE_Message_Queue< ACE_SYNCH_USE >::flush_i, ACE_Message_Queue< ACE_SYNCH_USE >::message_length, and ACE_Message_Queue< ACE_SYNCH_USE >::open.

template<ACE_SYNCH_DECL >

size_t ACE_Message_Queue::high_water_mark_ [protected]

Greatest number of bytes before blocking.

Definition at line 489 of file Message_Queue_T.h.
Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::high_water_mark, ACE_Message_Queue< ACE_SYNCH_USE >::is_full_i, and ACE_Message_Queue< ACE_SYNCH_USE >::open.

template<ACE_SYNCH_DECL >

ACE_SYNCH_MUTEX_T ACE_Message_Queue::lock_ [protected]

Protect queue from concurrent access.

Definition at line 505 of file Message_Queue_T.h.
Referenced by ACE_Message_Queue< ACE_MT_SYNCH >::lock.

template<ACE_SYNCH_DECL >

size_t ACE_Message_Queue::low_water_mark_ [protected]

Lowest number before unblocking occurs.

Definition at line 486 of file Message_Queue_T.h.
Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::dequeue_deadline_i, ACE_Message_Queue< ACE_SYNCH_USE >::dequeue_head_i, ACE_Message_Queue< ACE_SYNCH_USE >::dequeue_prio_i, ACE_Message_Queue< ACE_SYNCH_USE >::dequeue_tail_i, ACE_Message_Queue< ACE_SYNCH_USE >::low_water_mark, and ACE_Message_Queue< ACE_SYNCH_USE >::open.

template<ACE_SYNCH_DECL >

ACE_SYNCH_CONDITION_T ACE_Message_Queue::not_empty_cond_ [protected]

Used to make threads sleep until the queue is no longer empty.

Definition at line 508 of file Message_Queue_T.h.
Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::deactivate_i, ACE_Message_Queue< ACE_SYNCH_USE >::dump, and ACE_Message_Queue< ACE_SYNCH_USE >::signal_dequeue_waiters.

template<ACE_SYNCH_DECL >

ACE_SYNCH_CONDITION_T ACE_Message_Queue::not_full_cond_ [protected]

Used to make threads sleep until the queue is no longer full.

Definition at line 511 of file Message_Queue_T.h.
Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::deactivate_i, ACE_Message_Queue< ACE_SYNCH_USE >::dump, and ACE_Message_Queue< ACE_SYNCH_USE >::signal_enqueue_waiters.

template<ACE_SYNCH_DECL >

ACE_Notification_Strategy* ACE_Message_Queue::notification_strategy_ [protected]

The notification strategy used when a new message is enqueued.

Definition at line 501 of file Message_Queue_T.h.
Referenced by ACE_Message_Queue< ACE_SYNCH_USE >::notification_strategy, ACE_Message_Queue< ACE_SYNCH_USE >::notify, and ACE_Message_Queue< ACE_SYNCH_USE >::open.

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

Message_Queue_T.h

Generated on Mon Jun 16 12:50:33 2003 for ACE by

ACE_Message_Queue Class Template Reference

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