Teuchos_OpaqueWrapper.hpp

// @HEADER
// *****************************************************************************
//                    Teuchos: Common Tools Package
//
// Copyright 2004 NTESS and the Teuchos contributors.
// SPDX-License-Identifier: BSD-3-Clause
// *****************************************************************************
// @HEADER

#ifndef TEUCHOS_OPAQUE_WRAPPER_HPP
#define TEUCHOS_OPAQUE_WRAPPER_HPP


#include "Teuchos_RCP.hpp"


//#define TEUCHOS_OPAQUE_WRAPPER_ANNOUNCE_FREE

#ifdef TEUCHOS_OPAQUE_WRAPPER_ANNOUNCE_FREE
#  include "Teuchos_VerboseObject.hpp"
#endif // TEUCHOS_OPAQUE_WRAPPER_ANNOUNCE_FREE


namespace Teuchos {


template <class Opaque>
class OpaqueWrapper {
public:
  OpaqueWrapper( Opaque opaque )
    : opaque_(opaque)
    {}
  operator Opaque () const
    { return opaque_; }
  Opaque operator()() const
    { return opaque_; }
protected:
  Opaque  opaque_;
private:
  OpaqueWrapper(); // Not defined
  OpaqueWrapper(const OpaqueWrapper&); // Not defined
  OpaqueWrapper& operator=(const OpaqueWrapper&); // Not defined
};

template <class Opaque, class OpaqueFree>
class OpaqueWrapperWithFree : public OpaqueWrapper<Opaque> {
public:
  OpaqueWrapperWithFree( Opaque opaque, OpaqueFree opaqueFree )
    : OpaqueWrapper<Opaque>(opaque), opaqueFree_(opaqueFree)
  {}
  ~OpaqueWrapperWithFree()
  {
    // FIXME (mfh 10 Sep 2012) This only works if the free function is
    // a raw function pointer, not if it is a general "function object"
    // (i.e., something callable via operator()).
    if(opaqueFree_) {
#ifdef TEUCHOS_OPAQUE_WRAPPER_ANNOUNCE_FREE
      Teuchos::RCP<Teuchos::FancyOStream>
  out = Teuchos::VerboseObjectBase::getDefaultOStream();
      Teuchos::OSTab tab(out);
      *out << "\nOpaqueWrapperWithFree::~OpaqueWrapperWithFree(): Freeing opaque object"
     << " of type " << TypeNameTraits<Opaque>::name() << "!\n";
#endif // TEUCHOS_OPAQUE_WRAPPER_ANNOUNCE_FREE
      opaqueFree_(&this->opaque_);
    }
  }
private:
  OpaqueFree opaqueFree_;
  OpaqueWrapperWithFree(); // Not defined
  OpaqueWrapperWithFree(const OpaqueWrapperWithFree&); // Not defined
  OpaqueWrapperWithFree& operator=(const OpaqueWrapperWithFree&); // Not defined
};


template <class Opaque>
inline
RCP<OpaqueWrapper<Opaque> >
opaqueWrapper( Opaque opaque)
{
  return rcp(new OpaqueWrapper<Opaque>(opaque));
}


template <class Opaque, class OpaqueFree>
inline
RCP<OpaqueWrapper<Opaque> >
opaqueWrapper( Opaque opaque, OpaqueFree opaqueFree)
{
  return rcp(new OpaqueWrapperWithFree<Opaque,OpaqueFree>(opaque,opaqueFree));
}


} // namespace Teuchos


#endif  // TEUCHOS_OPAQUE_WRAPPER_HPP