ossimReferenced Class Reference

ossimReferenced allows for shared object ref counting if the reference count ever gets to 0 or less it will delete 'this' object. More...

#include <ossimReferenced.h>

Inheritance diagram for ossimReferenced:

Public Member Functions
	ossimReferenced ()
	ossimReferenced (const ossimReferenced &)
ossimReferenced &	operator= (const ossimReferenced &)
void	ref () const
	increment the reference count by one, indicating that this object has another pointer which is referencing it. More...
void	unref () const
	decrement the reference count by one, indicating that a pointer to this object is referencing it. More...
void	unref_nodelete () const
	decrement the reference count by one, indicating that a pointer to this object is referencing it. More...
int	referenceCount () const

Protected Member Functions
virtual	~ossimReferenced ()

Private Attributes
std::atomic_int	m_refCount

Detailed Description

ossimReferenced allows for shared object ref counting if the reference count ever gets to 0 or less it will delete 'this' object.

Currently uses std::mutex to control the locking of the reference count variable.

Eventually we would like to replace all of ossimReferenced and ossimRefPtr with C++11 std::shared_ptr

Definition at line 23 of file ossimReferenced.h.

Constructor & Destructor Documentation

ossimReferenced() [1/2]

ossimReferenced::ossimReferenced ( )

inline

Definition at line 26 of file ossimReferenced.h.

   : m_refCount(0)
      {}

ossimReferenced() [2/2]

ossimReferenced::ossimReferenced ( const ossimReferenced &  )

inline

Definition at line 30 of file ossimReferenced.h.

   : m_refCount(0)
   {}

~ossimReferenced()

ossimReferenced::~ossimReferenced ( )

protectedvirtual

Definition at line 6 of file ossimReferenced.cpp.

References ossimNotify(), ossimNotifyLevel_WARN, and referenceCount().

{
   int count = referenceCount();
   if (count>0)
   {
      ossimNotify(ossimNotifyLevel_WARN)<<"Warning: deleting still referenced object "<<this<<std::endl;
      ossimNotify(ossimNotifyLevel_WARN)<<"         the final reference count was "<<count
                                        <<", memory corruption possible."<<std::endl;
   }
}

Member Function Documentation

operator=()

ossimReferenced& ossimReferenced::operator= ( const ossimReferenced &  )

inline

Definition at line 33 of file ossimReferenced.h.

Referenced by ossim2dTo2dTransform::operator=(), and ossimTieGpt::operator=().

{ return *this; }

ref()

void ossimReferenced::ref ( ) const

inline

increment the reference count by one, indicating that this object has another pointer which is referencing it.

Definition at line 77 of file ossimReferenced.h.

References m_refCount.

Referenced by ossimImageHandlerMtAdaptor::getTile(), ossimUsgsDemTileSource::getTile(), ossimJpegTileSource::getTile(), ossimGpkgReader::getTile(), ossimHdf5ImageHandler::getTile(), ossimCcfTileSource::getTile(), ossimHdfReader::getTile(), ossimDtedTileSource::getTile(), ossimPngReader::getTile(), ossimH5ImageHandler::getTile(), ossimAdrgTileSource::getTile(), ossimTiffTileSource::getTile(), and ossimGeoPdfReader::getTile().

{
  ++m_refCount;
}

referenceCount()

int ossimReferenced::referenceCount ( ) const

inline

Returns

the number pointers currently referencing this object.

Definition at line 67 of file ossimReferenced.h.

Referenced by ~ossimReferenced().

{ return m_refCount.load(); }

unref()

void ossimReferenced::unref ( ) const

inline

decrement the reference count by one, indicating that a pointer to this object is referencing it.

If the reference count goes to zero, it is assumed that this object is no longer referenced and is automatically deleted.

Definition at line 82 of file ossimReferenced.h.

References m_refCount.

Referenced by ossimGdalOgrVectorAnnotation::deleteTables(), ossimImageHandlerMtAdaptor::getTile(), ossimUsgsDemTileSource::getTile(), ossimJpegTileSource::getTile(), ossimGpkgReader::getTile(), ossimHdf5ImageHandler::getTile(), ossimCcfTileSource::getTile(), ossimHdfReader::getTile(), ossimDtedTileSource::getTile(), ossimH5ImageHandler::getTile(), ossimPngReader::getTile(), ossimAdrgTileSource::getTile(), and ossimGeoPdfReader::getTile().

{
  bool needDelete = false;
  {
    // fetch_sub should return the value before subtraction.
    // so if 1 was before the subtraction that means it should
    // be zero after the subtraction so we will test <=1
    needDelete = m_refCount.fetch_sub(1) <= 1;
  }

  if (needDelete)
  {
    delete this;
  }
}

unref_nodelete()

void ossimReferenced::unref_nodelete ( ) const

inline

decrement the reference count by one, indicating that a pointer to this object is referencing it.

However, do not delete it, even if ref count goes to 0. Warning, unref_nodelete() should only be called if the user knows exactly who will be resonsible for, one should prefer unref() over unref_nodelete() as the later can lead to memory leaks.

Definition at line 58 of file ossimReferenced.h.

   { 
     // std::lock_guard<std::mutex> lock(theRefMutex); 
     --m_refCount;
   }

Member Data Documentation

m_refCount

std::atomic_int ossimReferenced::m_refCount

mutableprivate

Definition at line 74 of file ossimReferenced.h.

Referenced by ref(), and unref().

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

• ossimReferenced.h
• ossimReferenced.cpp