ACE  6.3.3
Public Types | Public Member Functions | Public Attributes | Protected Attributes | Private Member Functions | List of all members
ACE_Message_Queue_Base Class Referenceabstract

Base class for ACE_Message_Queue, which is the central queuing facility for messages in the ACE framework. More...

#include <Message_Queue.h>

Inheritance diagram for ACE_Message_Queue_Base:
Inheritance graph
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Public Types

enum  {
  DEFAULT_HWM = 16 * 1024, DEFAULT_LWM = 16 * 1024, ACTIVATED = 1, DEACTIVATED = 2,
  PULSED = 3
}
 

Public Member Functions

 ACE_Message_Queue_Base (void)
 
virtual int close (void)=0
 Close down the message queue and release all resources. More...
 
virtual ~ACE_Message_Queue_Base (void)
 Close down the message queue and release all resources. More...
 
virtual int peek_dequeue_head (ACE_Message_Block *&first_item, ACE_Time_Value *timeout=0)=0
 
virtual int enqueue_tail (ACE_Message_Block *new_item, ACE_Time_Value *timeout=0)=0
 
virtual int enqueue (ACE_Message_Block *new_item, ACE_Time_Value *timeout=0)=0
 
virtual int dequeue_head (ACE_Message_Block *&first_item, ACE_Time_Value *timeout=0)=0
 
virtual int dequeue (ACE_Message_Block *&first_item, ACE_Time_Value *timeout=0)=0
 
virtual bool is_full (void)=0
 True if queue is full, else false. More...
 
virtual bool is_empty (void)=0
 True if queue is empty, else false. More...
 
virtual size_t message_bytes (void)=0
 
virtual size_t message_length (void)=0
 
virtual size_t message_count (void)=0
 Number of total messages on the queue. More...
 
virtual void message_bytes (size_t new_size)=0
 
virtual void message_length (size_t new_length)=0
 
virtual int deactivate (void)=0
 
virtual int activate (void)=0
 
virtual int pulse (void)=0
 
virtual int state (void)
 Returns the current state of the queue. More...
 
virtual int deactivated (void)=0
 
virtual ACE_Notification_Strategynotification_strategy (void)=0
 Get the notification strategy for the Message_Queue. More...
 
virtual void notification_strategy (ACE_Notification_Strategy *s)=0
 Set the notification strategy for the Message_Queue. More...
 
virtual void dump (void) const =0
 Dump the state of an object. More...
 

Public Attributes

 ACE_ALLOC_HOOK_DECLARE
 Declare the dynamic allocation hooks. More...
 

Protected Attributes

int state_
 

Private Member Functions

 ACE_Message_Queue_Base (const ACE_Message_Queue_Base &)
 
void operator= (const ACE_Message_Queue_Base &)
 

Detailed Description

Base class for ACE_Message_Queue, which is the central queuing facility for messages in the ACE framework.

For all the ACE_Time_Value pointer parameters the caller will block until action is possible if timeout == 0. Otherwise, it will wait until the absolute time specified in *timeout elapses.

A queue is always in one of three states: . ACTIVATED . DEACTIVATED . PULSED

Member Enumeration Documentation

anonymous enum
Enumerator
DEFAULT_HWM 

Default high watermark (16 K).

DEFAULT_LWM 

Default low watermark (same as high water mark).

ACTIVATED 

Message queue is active and processing normally.

DEACTIVATED 

Queue is deactivated; no enqueue or dequeue operations allowed.

PULSED 

Message queue was pulsed; enqueue and dequeue may proceed normally.

Constructor & Destructor Documentation

ACE_Message_Queue_Base::ACE_Message_Queue_Base ( void  )
inline
ACE_Message_Queue_Base::~ACE_Message_Queue_Base ( void  )
virtual

Close down the message queue and release all resources.

ACE_Message_Queue_Base::ACE_Message_Queue_Base ( const ACE_Message_Queue_Base )
private

Member Function Documentation

virtual int ACE_Message_Queue_Base::activate ( void  )
pure virtual

Reactivate the queue so that threads can enqueue and dequeue messages again.

Return values
Thequeue's state before this call.

Implemented in ACE_Message_Queue< ACE_SYNCH_DECL, TIME_POLICY >, ACE_Message_Queue< ACE_SYNCH_USE, ACE_System_Time_Policy >, ACE_Message_Queue< ACE_SYNCH >, ACE_Message_Queue< ACE_MT_SYNCH >, ACE_Message_Queue< ACE_SYNCH_USE, TIME_POLICY >, and ACE_Message_Queue_NT.

virtual int ACE_Message_Queue_Base::close ( void  )
pure virtual
virtual int ACE_Message_Queue_Base::deactivate ( void  )
pure virtual

Deactivate the queue and wake up 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.

Return values
Thequeue's state before this call.

Implemented in ACE_Message_Queue< ACE_SYNCH_DECL, TIME_POLICY >, ACE_Message_Queue< ACE_SYNCH_USE, ACE_System_Time_Policy >, ACE_Message_Queue< ACE_SYNCH >, ACE_Message_Queue< ACE_MT_SYNCH >, ACE_Message_Queue< ACE_SYNCH_USE, TIME_POLICY >, and ACE_Message_Queue_NT.

virtual int ACE_Message_Queue_Base::deactivated ( void  )
pure virtual
virtual int ACE_Message_Queue_Base::dequeue ( ACE_Message_Block *&  first_item,
ACE_Time_Value timeout = 0 
)
pure virtual
virtual int ACE_Message_Queue_Base::dequeue_head ( ACE_Message_Block *&  first_item,
ACE_Time_Value timeout = 0 
)
pure virtual

Dequeue and return the <ACE_Message_Block *> at the head of the queue. Returns number of items in queue if the call succeeds or -1 otherwise. These calls return -1 when queue is closed, deactivated (in which case errno == ESHUTDOWN), when a signal occurs (in which case errno == EINTR, or if the time specified in timeout elapses (in which case errno == EWOULDBLOCK).

Implemented in ACE_Dynamic_Message_Queue< ACE_SYNCH_DECL, TIME_POLICY >, ACE_Message_Queue< ACE_SYNCH_DECL, TIME_POLICY >, ACE_Message_Queue< ACE_SYNCH_USE, ACE_System_Time_Policy >, ACE_Message_Queue< ACE_SYNCH >, ACE_Message_Queue< ACE_MT_SYNCH >, ACE_Message_Queue< ACE_SYNCH_USE, TIME_POLICY >, and ACE_Message_Queue_NT.

virtual void ACE_Message_Queue_Base::dump ( void  ) const
pure virtual
virtual int ACE_Message_Queue_Base::enqueue ( ACE_Message_Block new_item,
ACE_Time_Value timeout = 0 
)
pure virtual
virtual int ACE_Message_Queue_Base::enqueue_tail ( ACE_Message_Block new_item,
ACE_Time_Value timeout = 0 
)
pure virtual

Enqueue a <ACE_Message_Block *> into the tail of the queue. Returns number of items in queue if the call succeeds or -1 otherwise. These calls return -1 when queue is closed, deactivated (in which case errno == ESHUTDOWN), when a signal occurs (in which case errno == EINTR, or if the time specified in timeout elapses (in which case errno == EWOULDBLOCK).

Implemented in ACE_Dynamic_Message_Queue< ACE_SYNCH_DECL, TIME_POLICY >, ACE_Message_Queue< ACE_SYNCH_DECL, TIME_POLICY >, ACE_Message_Queue< ACE_SYNCH_USE, ACE_System_Time_Policy >, ACE_Message_Queue< ACE_SYNCH >, ACE_Message_Queue< ACE_MT_SYNCH >, ACE_Message_Queue< ACE_SYNCH_USE, TIME_POLICY >, and ACE_Message_Queue_NT.

virtual bool ACE_Message_Queue_Base::is_empty ( void  )
pure virtual
virtual bool ACE_Message_Queue_Base::is_full ( void  )
pure virtual
virtual size_t ACE_Message_Queue_Base::message_bytes ( void  )
pure virtual
virtual void ACE_Message_Queue_Base::message_bytes ( size_t  new_size)
pure virtual
virtual size_t ACE_Message_Queue_Base::message_count ( void  )
pure virtual
virtual size_t ACE_Message_Queue_Base::message_length ( void  )
pure virtual
virtual void ACE_Message_Queue_Base::message_length ( size_t  new_length)
pure virtual
virtual ACE_Notification_Strategy* ACE_Message_Queue_Base::notification_strategy ( void  )
pure virtual
virtual void ACE_Message_Queue_Base::notification_strategy ( ACE_Notification_Strategy s)
pure virtual
void ACE_Message_Queue_Base::operator= ( const ACE_Message_Queue_Base )
private
virtual int ACE_Message_Queue_Base::peek_dequeue_head ( ACE_Message_Block *&  first_item,
ACE_Time_Value timeout = 0 
)
pure virtual

Retrieve the first ACE_Message_Block without removing it. 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.

Implemented in ACE_Dynamic_Message_Queue< ACE_SYNCH_DECL, TIME_POLICY >, ACE_Message_Queue< ACE_SYNCH_DECL, TIME_POLICY >, ACE_Message_Queue< ACE_SYNCH_USE, ACE_System_Time_Policy >, ACE_Message_Queue< ACE_SYNCH >, ACE_Message_Queue< ACE_MT_SYNCH >, ACE_Message_Queue< ACE_SYNCH_USE, TIME_POLICY >, and ACE_Message_Queue_NT.

virtual int ACE_Message_Queue_Base::pulse ( void  )
pure 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.

Return values
Thequeue's state before this call.

Implemented in ACE_Message_Queue< ACE_SYNCH_DECL, TIME_POLICY >, ACE_Message_Queue< ACE_SYNCH_USE, ACE_System_Time_Policy >, ACE_Message_Queue< ACE_SYNCH >, ACE_Message_Queue< ACE_MT_SYNCH >, ACE_Message_Queue< ACE_SYNCH_USE, TIME_POLICY >, and ACE_Message_Queue_NT.

int ACE_Message_Queue_Base::state ( void  )
virtual

Member Data Documentation

ACE_Message_Queue_Base::ACE_ALLOC_HOOK_DECLARE

Declare the dynamic allocation hooks.

int ACE_Message_Queue_Base::state_
protected

Indicates the state of the queue, which can be <ACTIVATED>, <DEACTIVATED>, or <PULSED>.


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