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corelinux::Semaphore Class Reference

A Semaphore supports the protocol that processes and/or threads agree to follow for the purpose of controlled access to a resource. More...

#include <Semaphore.hpp>

Inheritance diagram for corelinux::Semaphore

[legend]Collaboration diagram for corelinux::Semaphore:

[legend]List of all members.

Public Methods
	Semaphore ( SemaphoreGroupPtr, SemaphoreIdentifierRef, bool Recursive=false, bool Balking=false ) throw ( NullPointerException )
	Default constructor requires the identifier of the semaphore in the semaphore group. More...
virtual	~Semaphore ( void )
	Virtual Destructor.
bool	operator== ( SemaphoreCref aRef ) const
	Equality operator returns true if identifiers match.
virtual bool	isBalkingEnabled ( void ) const
	Returns true if balking enabled.
virtual bool	isRecursionEnabled ( void ) const
	Returns true if recursion allowed.
virtual ThreadIdentifierCref	getOwningThreadIdentifier ( void ) const
	Returns the identifier of who currently owns the semaphore.
virtual CounterCref	getRecursionQueueLength ( void ) const
	Return the depth of the recursion for the owner.
Protected Methods
	Semaphore ( void ) throw (Assertion)
	Default constructor throws assertion.
	Semaphore ( SemaphoreCref ) throw (Assertion)
	Copy constructor throws assertion.
SemaphoreRef	operator= ( SemaphoreCref ) throw (Assertion)
	Assignment operator throws assertion.
CounterCref	operator++ ( void )
	Operator for increasing theRecursionQueueLength.
CounterCref	operator-- ( void )
	Operator for decreasing theRecursionQueueLength.
virtual ThreadIdentifierRef	getOwnerId ( void )
	Returns a reference to the owning thread.
virtual void	setOwnerId ( void )
	Sets the owner id to the current thread.
virtual void	setRecursionQueueLength ( Counter )
	Sets the recursion length.
virtual void	resetOwnerId ( void )
	Sets the owner thread id to not owned.

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Detailed Description

A Semaphore supports the protocol that processes and/or threads agree to follow for the purpose of controlled access to a resource.

The resource can be anything that the developer considers to need access controls on such as memory, hardware, methods, computer instructions, and so on.

Callers can elect to avoid being put into a blocked state and return immediately without control to the resource. Callers may also request that they are put into a blocked state for a specified amount of time. If, at the end of the specified time, the request has not been satisfied, it is returned with a Timeout indicator.

The owner or creator of the semaphore can elect to enforce balking behavior on a Semaphore. When so designated, the Semaphore can turn back any request until some condition in their solution space is met regardless of the callers blocking options. If a caller access attempt is balked, is it returned with a Balked indicator.

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Constructor & Destructor Documentation

corelinux::Semaphore::Semaphore ( SemaphoreGroupPtr aGroup, SemaphoreIdentifierRef aIdentifier, bool aRecursionFlag = false, bool aBalkingFlag = false ) throw ( NullPointerException )

Default constructor requires the identifier of the semaphore in the semaphore group. Parameters: SemaphoreGroupPtr   The owning SemaphoreGroup SemaphoreIdentifier   The identifier from the Semaphore Group bool   true if recursion enabled bool   true if balking enabled

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

• Semaphore.hpp
• Semaphore.cpp

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