This class defines a base class for thread-safe pointer to an object. More...

#include <safecoll.h>

Inheritance diagram for PSafePtrMultiThreaded:

Collaboration diagram for PSafePtrMultiThreaded:

Public Member Functions
virtual void	Assign (const PSafePtrMultiThreaded &ptr)

virtual void	Assign (const PSafePtrBase &ptr)

virtual void	Assign (const PSafeCollection &safeCollection)

virtual void	Assign (PSafeObject *obj)

virtual void	Assign (PINDEX idx)

Overrides from class PObject
virtual Comparison	Compare (const PObject &obj) const
	Compare the pointers. More...

Operations
virtual void	SetNULL ()
	Set the pointer to NULL, unlocking/dereferencing existing pointer value. More...

virtual PBoolean	SetSafetyMode (PSafetyMode mode)
	Change the locking mode used by this pointer. More...

Public Member Functions inherited from PSafePtrBase
virtual void	PrintOn (ostream &strm) const
	Output the contents of the object to the stream. More...

bool	operator! () const
	Return true if pointer is NULL. More...

PSafeObject *	GetObject () const
	Return pointer to safe object. More...

template<class T >
T *	GetObjectAs () const
	Return pointer to safe object. More...

PSafetyMode	GetSafetyMode () const
	Get the locking mode used by this pointer. More...

	~PSafePtrBase ()
	Unlock and dereference the PSafeObject this is pointing to. More...

Public Member Functions inherited from PObject
unsigned	GetTraceContextIdentifier () const
	Get PTRACE context identifier. More...

void	SetTraceContextIdentifier (unsigned id)

void	GetTraceContextIdentifier (PObject &obj)

void	GetTraceContextIdentifier (PObject *obj)

void	SetTraceContextIdentifier (const PObject &obj)

void	SetTraceContextIdentifier (const PObject *obj)

virtual	~PObject ()

virtual PObject *	Clone () const
	Create a copy of the class on the heap. More...

template<class CLS >
CLS *	CloneAs () const
	As for Clone() but converts to specified type. More...

virtual PINDEX	HashFunction () const
	This function yields a hash value required by the `PDictionary` class. More...

virtual const char *	GetClass (unsigned ancestor=0) const
	Get the current dynamic type of the object instance. More...

PBoolean	IsClass (const char *cls) const

virtual PBoolean	InternalIsDescendant (const char *clsName) const
	Determine if the dynamic type of the current instance is a descendent of the specified class. More...

__inline const PObject *	PTraceObjectInstance () const

virtual Comparison	CompareObjectMemoryDirect (const PObject &obj) const
	Determine the byte wise comparison of two objects. More...

bool	operator== (const PObject &obj) const
	Compare the two objects. More...

bool	operator!= (const PObject &obj) const
	Compare the two objects. More...

bool	operator< (const PObject &obj) const
	Compare the two objects. More...

bool	operator> (const PObject &obj) const
	Compare the two objects. More...

bool	operator<= (const PObject &obj) const
	Compare the two objects. More...

bool	operator>= (const PObject &obj) const
	Compare the two objects. More...

virtual void	ReadFrom (istream &strm)
	Input the contents of the object from the stream. More...

Protected Member Functions
virtual void	Next ()

virtual void	Previous ()

virtual void	DeleteObject (PSafeObject *obj)

virtual void	LockPtr ()

virtual void	UnlockPtr ()

Protected Member Functions inherited from PSafePtrBase
PBoolean	EnterSafetyMode (EnterSafetyModeOption ref)

void	ExitSafetyMode (ExitSafetyModeOption ref)

	PSafePtrBase (PSafeObject *obj=NULL, PSafetyMode mode=PSafeReference)
	Create a new pointer to a PSafeObject. More...

	PSafePtrBase (const PSafeCollection &safeCollection, PSafetyMode mode, PINDEX idx)
	Create a new pointer to a PSafeObject. More...

	PSafePtrBase (const PSafeCollection &safeCollection, PSafetyMode mode, PSafeObject *obj)
	Create a new pointer to a PSafeObject. More...

	PSafePtrBase (const PSafePtrBase &enumerator)
	Copy the pointer to the PSafeObject. More...

Protected Member Functions inherited from PObject
	PObject ()
	Constructor for PObject, made protected so cannot ever create one on its own. More...

Protected Attributes
PMutex	m_mutex

PSafeObject *	m_objectToDelete

Protected Attributes inherited from PSafePtrBase
const PSafeCollection *	collection

PSafeObject *	currentObject

PSafetyMode	lockMode

Protected Attributes inherited from PObject
unsigned	m_traceContextIdentifier

Construction
	PSafePtrMultiThreaded (PSafeObject *obj=NULL, PSafetyMode mode=PSafeReference)
	Create a new pointer to a PSafeObject. More...

	PSafePtrMultiThreaded (const PSafeCollection &safeCollection, PSafetyMode mode, PINDEX idx)
	Create a new pointer to a PSafeObject. More...

	PSafePtrMultiThreaded (const PSafeCollection &safeCollection, PSafetyMode mode, PSafeObject *obj)
	Create a new pointer to a PSafeObject. More...

	PSafePtrMultiThreaded (const PSafePtrMultiThreaded &enumerator)
	Copy the pointer to the PSafeObject. More...

	~PSafePtrMultiThreaded ()
	Unlock and dereference the PSafeObject this is pointing to. More...

Additional Inherited Members
Public Types inherited from PObject
enum	Comparison { LessThan = -1, EqualTo = 0, GreaterThan = 1 }
	Result of the comparison operation performed by the `Compare()` function. More...

Static Public Member Functions inherited from PObject
static const char *	Class ()
	Get the name of the class as a C string. More...

static __inline const PObject *	PTraceObjectInstance (const char *)

static __inline const PObject *	PTraceObjectInstance (const PObject *obj)

static Comparison	InternalCompareObjectMemoryDirect (const PObject obj1, const PObject obj2, PINDEX size)
	Internal function caled from CompareObjectMemoryDirect() More...

Protected Types inherited from PSafePtrBase
enum	EnterSafetyModeOption { WithReference, AlreadyReferenced }

enum	ExitSafetyModeOption { WithDereference, NoDereference }

Friends inherited from PObject

Detailed Description

This class defines a base class for thread-safe pointer to an object.

This is part of a set of classes to solve the general problem of a collection (eg a PList or PDictionary) of objects that needs to be a made thread safe. Any thread can add, read, write or remove an object with both the object and the database of objects itself kept thread safe.

NOTE: unlikel PSafePtrBase, pointers based on this class are thread safe themseleves, at the expense of performance on every operation.

See the PSafeObject class for more details.

Constructor & Destructor Documentation

PSafePtrMultiThreaded::PSafePtrMultiThreaded	(	PSafeObject *	obj = `NULL`,
		PSafetyMode	mode = `PSafeReference`
	)

protected

Create a new pointer to a PSafeObject.

An optional locking mode may be provided to lock the object for reading or writing and automatically unlock it on destruction.

Note that this version is not associated with a collection so the ++ and – operators will not work.

Parameters

obj	Physical object to point to.
mode	Locking mode for the object

PSafePtrMultiThreaded::PSafePtrMultiThreaded	(	const PSafeCollection &	safeCollection,
		PSafetyMode	mode,
		PINDEX	idx
	)

protected

Create a new pointer to a PSafeObject.

An optional locking mode may be provided to lock the object for reading or writing and automatically unlock it on destruction.

The idx'th entry of the collection is pointed to by this object. If the idx is beyond the size of the collection, the pointer is NULL.

Parameters

safeCollection	Collection pointer will enumerate
mode	Locking mode for the object
idx	Index into collection to point to

PSafePtrMultiThreaded::PSafePtrMultiThreaded	(	const PSafeCollection &	safeCollection,
		PSafetyMode	mode,
		PSafeObject *	obj
	)

protected

Create a new pointer to a PSafeObject.

An optional locking mode may be provided to lock the object for reading or writing and automatically unlock it on destruction.

The obj parameter is only set if it contained in the collection, otherwise the pointer is NULL.

Parameters

safeCollection	Collection pointer will enumerate
mode	Locking mode for the object
obj	Inital object in collection to point to

PSafePtrMultiThreaded::PSafePtrMultiThreaded ( const PSafePtrMultiThreaded & enumerator )

protected

Copy the pointer to the PSafeObject.

This will create a copy of the pointer with the same locking mode and lock on the PSafeObject. It will also increment the reference count on the PSafeObject as well.

Parameters

enumerator Pointer to copy

PSafePtrMultiThreaded::~PSafePtrMultiThreaded ( )

Unlock and dereference the PSafeObject this is pointing to.

Member Function Documentation

virtual void PSafePtrMultiThreaded::Assign ( const PSafePtrMultiThreaded & ptr )

virtual

virtual void PSafePtrMultiThreaded::Assign ( const PSafePtrBase & ptr )

virtual

Reimplemented from PSafePtrBase.

virtual void PSafePtrMultiThreaded::Assign ( const PSafeCollection & safeCollection )

virtual

Reimplemented from PSafePtrBase.

virtual void PSafePtrMultiThreaded::Assign ( PSafeObject * obj )

virtual

Reimplemented from PSafePtrBase.

virtual void PSafePtrMultiThreaded::Assign ( PINDEX idx )

virtual

Reimplemented from PSafePtrBase.

virtual Comparison PSafePtrMultiThreaded::Compare ( const PObject & obj ) const

virtual

Compare the pointers.

Note this is not a value comparison and will only return EqualTo if the two PSafePtrBase instances are pointing to the same instance.

Parameters

obj	Other instance to compare against

Reimplemented from PSafePtrBase.

virtual void PSafePtrMultiThreaded::DeleteObject ( PSafeObject * obj )

protectedvirtual

Reimplemented from PSafePtrBase.

virtual void PSafePtrMultiThreaded::LockPtr ( )

inlineprotectedvirtual

Reimplemented from PSafePtrBase.

References m_mutex.

virtual void PSafePtrMultiThreaded::Next ( )

protectedvirtual

Reimplemented from PSafePtrBase.

virtual void PSafePtrMultiThreaded::Previous ( )

protectedvirtual

Reimplemented from PSafePtrBase.

virtual void PSafePtrMultiThreaded::SetNULL ( )

virtual

Set the pointer to NULL, unlocking/dereferencing existing pointer value.

Reimplemented from PSafePtrBase.

virtual PBoolean PSafePtrMultiThreaded::SetSafetyMode ( PSafetyMode mode )

virtual

Change the locking mode used by this pointer.

If the function returns false, then the object has been flagged for deletion and the calling thread should immediately cease use of the object. This instance pointer will be set to NULL.

Parameters

mode	New locking mode

Reimplemented from PSafePtrBase.

virtual void PSafePtrMultiThreaded::UnlockPtr ( )

protectedvirtual

Reimplemented from PSafePtrBase.

Member Data Documentation

PMutex PSafePtrMultiThreaded::m_mutex

mutableprotected

Referenced by LockPtr().

PSafeObject* PSafePtrMultiThreaded::m_objectToDelete

protected

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

safecoll.h

Public Member Functions

Protected Member Functions

Protected Attributes

Construction

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation