PTLib  Version 2.10.4
PSafePtrMultiThreaded Class Reference

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

#include <safecoll.h>

Inheritance diagram for PSafePtrMultiThreaded:
PSafePtrBase PObject

List of all members.

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.
Operations
virtual void SetNULL ()
 Set the pointer to NULL, unlocking/dereferencing existing pointer value.
virtual PBoolean SetSafetyMode (PSafetyMode mode)
 Change the locking mode used by this pointer.

Protected Member Functions

virtual void Next ()
virtual void Previous ()
virtual void DeleteObject (PSafeObject *obj)
void Lock ()
void Unlock ()

Protected Attributes

PMutex m_mutex
PSafeObjectm_objectToDelete

Construction

 PSafePtrMultiThreaded (PSafeObject *obj=NULL, PSafetyMode mode=PSafeReference)
 Create a new pointer to a PSafeObject.
 PSafePtrMultiThreaded (const PSafeCollection &safeCollection, PSafetyMode mode, PINDEX idx)
 Create a new pointer to a PSafeObject.
 PSafePtrMultiThreaded (const PSafeCollection &safeCollection, PSafetyMode mode, PSafeObject *obj)
 Create a new pointer to a PSafeObject.
 PSafePtrMultiThreaded (const PSafePtrMultiThreaded &enumerator)
 Copy the pointer to the PSafeObject.
 ~PSafePtrMultiThreaded ()
 Unlock and dereference the PSafeObject this is pointing to.

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

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:
objPhysical object to point to.
modeLocking 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:
safeCollectionCollection pointer will enumerate
modeLocking mode for the object
idxIndex 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:
safeCollectionCollection pointer will enumerate
modeLocking mode for the object
objInital object in collection to point to

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:
enumeratorPointer to copy

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:
objOther instance to compare against

Reimplemented from PSafePtrBase.

virtual void PSafePtrMultiThreaded::DeleteObject ( PSafeObject obj) [protected, virtual]

Reimplemented from PSafePtrBase.

void PSafePtrMultiThreaded::Lock ( ) [inline, protected]

References m_mutex.

virtual void PSafePtrMultiThreaded::Next ( ) [protected, virtual]

Reimplemented from PSafePtrBase.

virtual void PSafePtrMultiThreaded::Previous ( ) [protected, virtual]

Reimplemented from PSafePtrBase.

virtual void PSafePtrMultiThreaded::SetNULL ( ) [virtual]

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

Reimplemented from PSafePtrBase.

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:
modeNew locking mode

Reimplemented from PSafePtrBase.

void PSafePtrMultiThreaded::Unlock ( ) [protected]

Member Data Documentation

PMutex PSafePtrMultiThreaded::m_mutex [mutable, protected]

Referenced by Lock().


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