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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::

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	waitZero (SemaphoreGroupPtr, Int, Int, Int)
	Called by the base semaphore to wait for a specific semaphore to have a zero value. 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

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

Called by the base semaphore to wait for a specific semaphore to have a zero value. 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