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corelinux::SemaphoreCommon Class Reference

The SemaphoreCommon manages the SemaphoreGroup common storage area. More...

#include <SemaphoreCommon.hpp>

Inheritance diagram for corelinux::SemaphoreCommon

[legend]Collaboration diagram for corelinux::SemaphoreCommon:

[legend]List of all members.

Static Public Methods
Int	getSemaphoreMaxValue ( SemaphoreGroupPtr, Int )
	Returns the maximum value for a semaphore as defined by the original semaphore claimant. More...
void	groupDefined ( SemaphoreGroupPtr )
	When a shared semaphore group is created, it is updated in the CSA, either by increasing the count of processes accessing a particular group, or adding to the csa initially. More...
Int	groupUnDefined ( SemaphoreGroupPtr )
	When the local process is deleting a semaphore group and it is considered a shared group, we are asked to adjust the map accordingly. More...
Int	setLock ( SemaphoreGroupPtr, Int, Int, Int )
	Called by the base semaphore to aquire a lock for a specific semaphore. More...
Int	setUnLock ( SemaphoreGroupPtr, Int, Int, Int )
	Called by the base semaphore to relinquish a lock for a specific semaphore. More...
Int	obtainSemaphore ( SemaphoreGroupPtr, Int, IntRef, IntRef, IntRef, Int )
	Typically called by a SemaphoreGroup prior to passing out the semaphore type to the caller. More...
Int	relinquishSemaphore (SemaphoreGroupPtr,Int)
	Called when the semaphore is no longer being referenced. More...
Int	setMaxValue ( SemaphoreGroupPtr, Int, Int )
	Called to set the semaphore maximum value. More...
Protected Methods
	SemaphoreCommon ( void )
	Default constructor used by class.
virtual	~SemaphoreCommon ( void )
	Destructor.
void	registerGroup ( SemaphoreGroupPtr )
	Does the work of getting the group registered in the CSA. More...
Int	deregisterGroup ( SemaphoreGroupPtr )
	Does the work of reducing the group share count, or marking the group for reclaimation. More...
Int	claimSemaphore ( SemaphoreGroupPtr, Int, IntRef, IntRef, IntRef, Int )
	Called when the group is determined to be shared and a semaphore share is to be claimed. More...
Int	reclaimSemaphore (SemaphoreGroupPtr,Int)
	Called when a group wishes to let the CSA reclaim a semaphore share. More...
CSAGrpHeaderPtr	findGroup ( IntCref , IntCref , CSAGrpHeaderPtr )
	Attempt to locate a specific group.
CSAGrpHeaderPtr	findAvailableGroup ( IntCref , IntCref , CSAGrpHeaderPtr )
	Find open slot that fits count criteria.
CSAGrpHeaderPtr	subsetGroup ( Int, CSAGrpHeaderPtr )
	Utility to clean CSA group tail.
CSAGrpHeaderPtr	combineGroup ( Int, CSAGrpHeaderPtr )
bool	isOriginator ( void ) const
Int	getOriginatorId ( void ) const
Int	canonicalUndefined ( void )
Static Protected Methods
void	createAttachment ( void )
	Factory for CSA.
void	exitAttachment ( void )
	On the way out from run-time.
Friends
class	CoreLinuxGuardPool

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Detailed Description

The SemaphoreCommon manages the SemaphoreGroup common storage area.

This area is to communicate between address spaces when using one of the CoreLinux++ SemaphoreGroup types in public mode.

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Member Function Documentation

Int corelinux::SemaphoreCommon::claimSemaphore ( SemaphoreGroupPtr aGroup, Int aSemIndex, IntRef aMaxValue, IntRef aRecurse, IntRef aBalking, Int aFailConstraint ) [protected]

Called when the group is determined to be shared and a semaphore share is to be claimed. Parameters: SemaphoreGroup   the group pointer Int   the semaphore identifier/index -1 = any Int   the initial value (becomes the max if new) IntRef   the recursive condition IntRef   the balking condition Int   0 must not exist, 1 share, 2 must exist

Int corelinux::SemaphoreCommon::deregisterGroup ( SemaphoreGroupPtr aGroup ) [protected]

Does the work of reducing the group share count, or marking the group for reclaimation. Parameters: SemaphoreGroup   pointer to register

Int corelinux::SemaphoreCommon::getSemaphoreMaxValue ( SemaphoreGroupPtr aGroup, Int aSemId ) [static]

Returns the maximum value for a semaphore as defined by the original semaphore claimant. Parameters: SemaphoreGroup   pointer to group owner Int   zero offset semaphore identifier Returns: Int -1 for local unknown, > 0 for common

void corelinux::SemaphoreCommon::groupDefined ( SemaphoreGroupPtr aGroup ) [static]

When a shared semaphore group is created, it is updated in the CSA, either by increasing the count of processes accessing a particular group, or adding to the csa initially. Parameters: SemaphoreGroup   pointer

Int corelinux::SemaphoreCommon::groupUnDefined ( SemaphoreGroupPtr aGroup ) [static]

When the local process is deleting a semaphore group and it is considered a shared group, we are asked to adjust the map accordingly. Parameters: SemaphoreGroup   pointer to the group Returns: Int number of shares on group

Int corelinux::SemaphoreCommon::obtainSemaphore ( SemaphoreGroupPtr aGroup, Int aSemIndex, IntRef aMaxValue, IntRef aRecurse, IntRef aBalking, Int aFailConstraint ) [static]

Typically called by a SemaphoreGroup prior to passing out the semaphore type to the caller. Parameters: SemaphoreGroup   the group pointer Int   the semaphore identifier/index -1 = any Int   reference the initial value (becomes the max if new) Int   reference the recursive condition Int   reference the balking condition Int   0 must not exist, 1 share, 2 must exist

Int corelinux::SemaphoreCommon::reclaimSemaphore ( SemaphoreGroupPtr aGroup, Int aSemIndex ) [protected]

Called when a group wishes to let the CSA reclaim a semaphore share. Parameters: SemaphoreGroup   the group pointer Int   the semaphore identifier/index Returns: Int the number of shares outstanding

void corelinux::SemaphoreCommon::registerGroup ( SemaphoreGroupPtr aGroup ) [protected]

Does the work of getting the group registered in the CSA. Parameters: SemaphoreGroup   pointer to register

Int corelinux::SemaphoreCommon::relinquishSemaphore ( SemaphoreGroupPtr aGroup, Int aSemIndex ) [static]

Called when the semaphore is no longer being referenced. Effectively reducing the share count for shared group semaphores Parameters: SemaphoreGroup   pointer Int   the zero index semaphore identifier Returns: Int the number of outstanding shares

Int corelinux::SemaphoreCommon::setLock ( SemaphoreGroupPtr aGroup, Int aGid, Int aSid, Int aFlg ) [static]

Called by the base semaphore to aquire a lock for a specific semaphore. Parameters: SemaphoreGroup   pointer to the group Int   the system group id Int   the zero offset semaphore id Int   the system dependent flag Returns: Int return code

Int corelinux::SemaphoreCommon::setMaxValue ( SemaphoreGroupPtr aGroup, Int aId, Int aValue ) [static]

Called to set the semaphore maximum value. For local this is SETVAL, for shared it is ignored Parameters: SemaphoreGroup   pointer Int   the zero index semaphore identifier Int   the value

Int corelinux::SemaphoreCommon::setUnLock ( SemaphoreGroupPtr aGroup, Int aGid, Int aSid, Int aFlg ) [static]

Called by the base semaphore to relinquish a lock for a specific semaphore. Parameters: SemaphoreGroup   pointer to the group Int   the system group id Int   the zero offset semaphore id Int   the system dependent flag Returns: Int return code

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

• SemaphoreCommon.hpp
• SemaphoreCommon.cpp

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This is the CoreLinux++ reference manual
Provided by The CoreLinux Consortium