include/comphelper/make_shared_from_uno.hxx

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  19 #ifndef INCLUDED_COMPHELPER_MAKE_SHARED_FROM_UNO_HXX
  20 #define INCLUDED_COMPHELPER_MAKE_SHARED_FROM_UNO_HXX
  21
  22 #include "boost/shared_ptr.hpp"
  23 #include <functional>
  24
  25 namespace comphelper {
  26
  27 /// @internal
  28 namespace detail {
  29 /// @internal
  30 template <typename T> struct ReleaseFunc : ::std::unary_function<T *, void> {
  31     void operator()( T * p ) const { p->release(); }
  32 };
  33 } // namespace detail
  34
  35 /** Makes a boost::shared_ptr from a ref-counted UNO object pointer.
  36     This makes sense if the object is used via UNO (implementing some X
  37     interface) and also internally using its implementation class, e.g.
  38
  39     <pre>
  40         boost::shared_ptr<MyUnoImpl> const ptr(
  41             comphelper::make_shared_from_UNO( new MyUnoImpl ) );
  42         ...
  43         xUno->callingUno( uno::Reference<XSomeInterface>( ptr.get() ) );
  44         ...
  45         takeSharedPtr( ptr );
  46         ...
  47     </pre>
  48
  49     @attention The shared_ptr operates on a separate reference counter, so
  50                weak pointers (boost::weak_ptr) are invalidated when the last
  51                shared_ptr is destroyed, although the UNO object may still be
  52                alive.
  53
  54     @param p object pointer
  55     @return shared_ptr to object
  56 */
  57 template <typename T>
  58 inline ::boost::shared_ptr<T> make_shared_from_UNO( T * p )
  59 {
  60     p->acquire();
  61     return ::boost::shared_ptr<T>( p, detail::ReleaseFunc<T>() );
  62 }
  63
  64 } // namespace comphelper
  65
  66 #endif // ! defined(INCLUDED_COMPHELPER_MAKE_SHARED_FROM_UNO_HXX)
  67
  68 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */