An abstract base class which provides dynamic priority evaluation methods for use by the ACE_Dynamic_Message_Queue class or any other class which needs to manage the priorities of a collection of ACE_Message_Blocks dynamically. More...

#include <Dynamic_Message_Strategy.h>

Inheritance diagram for ACE_Dynamic_Message_Strategy:

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Collaboration diagram for ACE_Dynamic_Message_Strategy:

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Public Types
enum	Priority_Status { PENDING = 0x01, LATE = 0x02, BEYOND_LATE = 0x04, ANY_STATUS = 0x07 }

Public Member Functions
	ACE_Dynamic_Message_Strategy (unsigned long static_bit_field_mask, unsigned long static_bit_field_shift, unsigned long dynamic_priority_max, unsigned long dynamic_priority_offset)
	Constructor. More...

virtual	~ACE_Dynamic_Message_Strategy (void)
	Virtual destructor. More...

Priority_Status	priority_status (ACE_Message_Block &mb, const ACE_Time_Value &tv)
	Updates the message's priority and returns its priority status. More...

unsigned long	static_bit_field_mask (void) const
	Get static bit field mask. More...

void	static_bit_field_mask (unsigned long)
	Set static bit field mask. More...

unsigned long	static_bit_field_shift (void) const
	Get left shift value to make room for static bit field. More...

void	static_bit_field_shift (unsigned long)
	Set left shift value to make room for static bit field. More...

unsigned long	dynamic_priority_max (void) const
	Get maximum supported priority value. More...

void	dynamic_priority_max (unsigned long)
	Set maximum supported priority value. More...

unsigned long	dynamic_priority_offset (void) const
	Get offset to boundary between signed range and unsigned range. More...

void	dynamic_priority_offset (unsigned long)
	Set offset to boundary between signed range and unsigned range. More...

virtual void	dump (void) const
	Dump the state of the strategy. More...

Protected Member Functions
virtual void	convert_priority (ACE_Time_Value &priority, const ACE_Message_Block &mb)=0
	Hook method for dynamic priority conversion. More...

Protected Attributes
unsigned long	static_bit_field_mask_
	This is a bit mask with all ones in the static bit field. More...

unsigned long	static_bit_field_shift_

unsigned long	dynamic_priority_max_
	Maximum supported priority value. More...

unsigned long	dynamic_priority_offset_
	Offset to boundary between signed range and unsigned range. More...

ACE_Time_Value	max_late_
	Maximum late time value that can be represented. More...

ACE_Time_Value	min_pending_
	Minimum pending time value that can be represented. More...

ACE_Time_Value	pending_shift_
	Time value by which to shift pending priority. More...

Detailed Description

An abstract base class which provides dynamic priority evaluation methods for use by the ACE_Dynamic_Message_Queue class or any other class which needs to manage the priorities of a collection of ACE_Message_Blocks dynamically.

Methods for deadline and laxity based priority evaluation are provided. These methods assume a specific partitioning of the message priority number into a higher order dynamic bit field and a lower order static priority bit field. The default partitioning assumes an unsigned dynamic message priority field of 22 bits and an unsigned static message priority field of 10 bits. This corresponds to the initial values of the static class members. To provide a different partitioning, assign a different set of values to the static class members before using the static member functions.

Member Enumeration Documentation

enum ACE_Dynamic_Message_Strategy::Priority_Status

Message priority status Values are defined as bit flags so that status combinations may be specified easily.

Enumerator
PENDING	Message can still make its deadline.
LATE	Message cannot make its deadline.
BEYOND_LATE	Message is so late its priority is undefined.
ANY_STATUS	Mask to match any priority status.

Constructor & Destructor Documentation

ACE_Dynamic_Message_Strategy::ACE_Dynamic_Message_Strategy	(	unsigned long	static_bit_field_mask,
		unsigned long	static_bit_field_shift,
		unsigned long	dynamic_priority_max,
		unsigned long	dynamic_priority_offset
	)

Constructor.

ACE_Dynamic_Message_Strategy::~ACE_Dynamic_Message_Strategy ( void )

virtual

Virtual destructor.

Member Function Documentation

virtual void ACE_Dynamic_Message_Strategy::convert_priority	(	ACE_Time_Value &	priority,
		const ACE_Message_Block &	mb
	)

protectedpure virtual

Hook method for dynamic priority conversion.

Implemented in ACE_Laxity_Message_Strategy, and ACE_Deadline_Message_Strategy.

void ACE_Dynamic_Message_Strategy::dump ( void ) const

virtual

Dump the state of the strategy.

Reimplemented in ACE_Laxity_Message_Strategy, and ACE_Deadline_Message_Strategy.

unsigned long ACE_Dynamic_Message_Strategy::dynamic_priority_max ( void ) const

inline

Get maximum supported priority value.

void ACE_Dynamic_Message_Strategy::dynamic_priority_max ( unsigned long ul )

inline

Set maximum supported priority value.

unsigned long ACE_Dynamic_Message_Strategy::dynamic_priority_offset ( void ) const

inline

Get offset to boundary between signed range and unsigned range.

void ACE_Dynamic_Message_Strategy::dynamic_priority_offset ( unsigned long ul )

inline

Set offset to boundary between signed range and unsigned range.

ACE_Dynamic_Message_Strategy::Priority_Status ACE_Dynamic_Message_Strategy::priority_status	(	ACE_Message_Block &	mb,
		const ACE_Time_Value &	tv
	)

Updates the message's priority and returns its priority status.

unsigned long ACE_Dynamic_Message_Strategy::static_bit_field_mask ( void ) const

inline

Get static bit field mask.

void ACE_Dynamic_Message_Strategy::static_bit_field_mask ( unsigned long ul )

inline

Set static bit field mask.

unsigned long ACE_Dynamic_Message_Strategy::static_bit_field_shift ( void ) const

inline

Get left shift value to make room for static bit field.

void ACE_Dynamic_Message_Strategy::static_bit_field_shift ( unsigned long ul )

inline

Set left shift value to make room for static bit field.

Member Data Documentation

unsigned long ACE_Dynamic_Message_Strategy::dynamic_priority_max_

protected

Maximum supported priority value.

unsigned long ACE_Dynamic_Message_Strategy::dynamic_priority_offset_

protected

Offset to boundary between signed range and unsigned range.

ACE_Time_Value ACE_Dynamic_Message_Strategy::max_late_

protected

Maximum late time value that can be represented.

ACE_Time_Value ACE_Dynamic_Message_Strategy::min_pending_

protected

Minimum pending time value that can be represented.

ACE_Time_Value ACE_Dynamic_Message_Strategy::pending_shift_

protected

Time value by which to shift pending priority.

unsigned long ACE_Dynamic_Message_Strategy::static_bit_field_mask_

protected

This is a bit mask with all ones in the static bit field.

unsigned long ACE_Dynamic_Message_Strategy::static_bit_field_shift_

protected

This is a left shift value to make room for static bit field: this value should be the logarithm base 2 of (static_bit_field_mask_ + 1).

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

Public Types

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation