itk::ConditionVariable Class Reference

#include <itkConditionVariable.h>

Inheritance diagram for itk::ConditionVariable:

Collaboration diagram for itk::ConditionVariable:

Detailed Description

A thread synchronization object used to suspend execution until some condition on shared data is met.

A thread calls Wait() to suspend its execution until the condition is met. Each call to Signal() from an executing thread will then cause a single waiting thread to be released. A call to Signal() means, "signal that the condition is true." Broadcast() releases all threads waiting on the condition variable.

The ITK ConditionVariable implementation is consistent with the standard definition and use of condition variables in pthreads and other common thread libraries.

IMPORTANT: A condition variable always requires an associated SimpleMutexLock object. The mutex object is used to avoid a dangerous race condition when Wait() and Signal() are called simultaneously from two different threads.

On systems using pthreads, this implementation abstract the standard calls to the pthread condition variable. On Win32 systems, there is no system provided condition variable. This class implements a condition variable using a critical section, a semphore, an event and a number of counters. The implementation is almost an extract translation of the implementation presented by Douglas C Schmidt and Irfan Pyarali in "Strategies for Implementing POSIX Condition Variables on Win32". This article can be found at http://www.cs.wustl.edu/~schmidt/win32-cv-1.html

Definition at line 58 of file itkConditionVariable.h.

Public Types
typedef SmartPointer< const Self >	ConstPointer
typedef SmartPointer< Self >	Pointer
typedef ConditionVariable	Self
typedef LightObject	Superclass
Public Types inherited from itk::LightObject
typedef SmartPointer< const Self >	ConstPointer
typedef SmartPointer< Self >	Pointer
typedef LightObject	Self

Public Member Functions
void	Broadcast ()
virtual ::itk::LightObject::Pointer	CreateAnother (void) const
virtual const char *	GetNameOfClass () const
void	Signal ()
void	Wait (SimpleMutexLock *mutex)
Public Member Functions inherited from itk::LightObject
virtual void	Delete ()
virtual int	GetReferenceCount () const
	itkCloneMacro (Self)
void	Print (std::ostream &os, Indent indent=0) const
virtual void	Register () const
virtual void	SetReferenceCount (int)
virtual void	UnRegister () const

Static Public Member Functions
static Pointer	New ()
Static Public Member Functions inherited from itk::LightObject
static void	BreakOnError ()
static Pointer	New ()

Protected Member Functions
	ConditionVariable ()
	~ConditionVariable ()
Protected Member Functions inherited from itk::LightObject
virtual LightObject::Pointer	InternalClone () const
	LightObject ()
virtual void	PrintHeader (std::ostream &os, Indent indent) const
virtual void	PrintSelf (std::ostream &os, Indent indent) const
virtual void	PrintTrailer (std::ostream &os, Indent indent) const
virtual	~LightObject ()

Private Member Functions
	ConditionVariable (const Self &other)
const Self &	operator= (const Self &)

Private Attributes
ConditionVariableType	m_ConditionVariable

Additional Inherited Members
Protected Types inherited from itk::LightObject
typedef int	InternalReferenceCountType
Protected Attributes inherited from itk::LightObject
InternalReferenceCountType	m_ReferenceCount
SimpleFastMutexLock	m_ReferenceCountLock

Member Typedef Documentation

typedef SmartPointer< const Self > itk::ConditionVariable::ConstPointer

Definition at line 65 of file itkConditionVariable.h.

typedef SmartPointer< Self > itk::ConditionVariable::Pointer

Definition at line 64 of file itkConditionVariable.h.

typedef ConditionVariable itk::ConditionVariable::Self

Standard class typedefs.

Definition at line 62 of file itkConditionVariable.h.

typedef LightObject itk::ConditionVariable::Superclass

Definition at line 63 of file itkConditionVariable.h.

Constructor & Destructor Documentation

itk::ConditionVariable::ConditionVariable ( )

protected

itk::ConditionVariable::~ConditionVariable ( )

protected

itk::ConditionVariable::ConditionVariable ( const Self &  other )

private

Member Function Documentation

void itk::ConditionVariable::Broadcast

(

)

Signal that the condition is true and release all waiting threads

virtual::itk::LightObject::Pointer itk::ConditionVariable::CreateAnother ( void  ) const

virtual

Create an object from an instance, potentially deferring to a factory. This method allows you to create an instance of an object that is exactly the same type as the referring object. This is useful in cases where an object has been cast back to a base class.

Reimplemented from itk::LightObject.

virtual const char* itk::ConditionVariable::GetNameOfClass ( ) const

virtual

Run-time type information (and related methods).

Reimplemented from itk::LightObject.

static Pointer itk::ConditionVariable::New ( )

static

Method for creation through the object factory.

const Self& itk::ConditionVariable::operator= ( const Self &  )

private

void itk::ConditionVariable::Signal

(

)

Signal that the condition is true and release one waiting thread

void itk::ConditionVariable::Wait

(

SimpleMutexLock *

mutex

)

Suspend execution of this thread until the condition is signaled. The argument is a SimpleMutex object that must be locked prior to calling this method.

Member Data Documentation

ConditionVariableType itk::ConditionVariable::m_ConditionVariable

private

Definition at line 92 of file itkConditionVariable.h.

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

• itkConditionVariable.h