[limal-commit] r2681 - /limal-branches/mc-devel/limal-ca-mgm/src/limal/PtrTypes.hpp

Author: mcalmer Date: Sun Jul 4 17:08:27 2010 New Revision: 2681 URL: http://svn.opensuse.org/viewcvs/limal?rev=2681&view=rev Log: add PtrTypes Added: limal-branches/mc-devel/limal-ca-mgm/src/limal/PtrTypes.hpp Added: limal-branches/mc-devel/limal-ca-mgm/src/limal/PtrTypes.hpp URL: http://svn.opensuse.org/viewcvs/limal/limal-branches/mc-devel/limal-ca-mgm/src/limal/PtrTypes.hpp?rev=2681&view=auto ============================================================================== --- limal-branches/mc-devel/limal-ca-mgm/src/limal/PtrTypes.hpp (added) +++ limal-branches/mc-devel/limal-ca-mgm/src/limal/PtrTypes.hpp Sun Jul 4 17:08:27 2010 @@ -0,0 +1,506 @@ +/*---------------------------------------------------------------------\ +| ____ _ __ __ ___ | +| |__ / \ / / . \ . \ | +| / / \ V /| _/ _/ | +| / /__ | | | | | | | +| /_____||_| |_| |_| | +| | +\---------------------------------------------------------------------*/ +/** \file limal/PtrTypes.h +*/ +#ifndef LIMAL_BASE_PTRTYPES_H +#define LIMAL_BASE_PTRTYPES_H + +#include <string> + +#include +#include +#include +#include + +/////////////////////////////////////////////////////////////////// +namespace ca_mgm +{ ///////////////////////////////////////////////////////////////// + + /** \defgroup ZYPP_SMART_PTR Smart pointer types + * Smart pointer types. + * + * Namespace ca_mgm provides 3 smart pointer types \b using the + * boost smart pointer library. + * + * \li \c scoped_ptr Simple sole ownership of single objects. Noncopyable. + * + * \li \c shared_ptr Object ownership shared among multiple pointers + * + * \li \c weak_ptr Non-owning observers of an object owned by shared_ptr. + * + * And \ref ca_mgm::RW_pointer, as wrapper around a smart pointer, + * poviding \c const correct read/write access to the object it refers. + */ + /*@{*/ + + /** shared_ptr custom deleter doing nothing. + * A custom deleter is a function being called when the + * last shared_ptr goes out of score. Per default the + * object gets deleted, but you can insall custom deleters + * as well. This one does nothing. + * + * \code + * // Some class providing a std::istream + * struct InpuStream + * { + * // Per deafult use std::cin. + * InputStream() + * : _stream( &std::cin, NullDeleter() ) + * {} + * // Or read from a file. + * InputStream( const Pathname & file_r ) + * : _stream( new ifgzstream( _path.asString().c_str() ) ) + * {} + * // Or use a stream priovided by the application. + * InputStream( std::istream & stream_r ) + * : _stream( &stream_r, NullDeleter() ) + * {} + * + * std::istream & stream() + * { return *_stream; } + * + * private: + * shared_ptrstd::istream _stream; + * }; + * \endcode + */ + struct NullDeleter + { + void operator()( const void *const ) const + {} + }; + + /** \class scoped_ptr */ + using boost::scoped_ptr; + + /** \class shared_ptr */ + using boost::shared_ptr; + + /** \class weak_ptr */ + using boost::weak_ptr; + + /** \class intrusive_ptr */ + using boost::intrusive_ptr; + + /** */ + using boost::static_pointer_cast; + /** */ + using boost::const_pointer_cast; + /** */ + using boost::dynamic_pointer_cast; + + ///////////////////////////////////////////////////////////////// +} // namespace ca_mgm +/////////////////////////////////////////////////////////////////// +/////////////////////////////////////////////////////////////////// +namespace std +{ ///////////////////////////////////////////////////////////////// + + // namespace sub { + // class Foo; + // typedef ca_mgm::intrusive_ptr<Foo> Foo_Ptr; // see DEFINE_PTR_TYPE(NAME) macro below + // } + + // Defined in namespace std g++ finds the output operator (König-Lookup), + // even if we typedef the pointer in a different namespace than ::ca_mgm. + // Otherwise we had to define an output operator always in the same namespace + // as the typedef (else g++ will just print the pointer value). + + /** \relates ca_mgm::shared_ptr Stream output. */ + template<class _D> + inline std::ostream & operator<<( std::ostream & str, const ca_mgm::shared_ptr<_D> & obj ) + { + if ( obj ) + return str << *obj; + return str << std::string("NULL"); + } + /** \relates ca_mgm::shared_ptr Stream output. */ + template<class _D> + inline std::ostream & dumpOn( std::ostream & str, const ca_mgm::shared_ptr<_D> & obj ) + { + if ( obj ) + return dumpOn( str, *obj ); + return str << std::string("NULL"); + } + + /** \relates ca_mgm::intrusive_ptr Stream output. */ + template<class _D> + inline std::ostream & operator<<( std::ostream & str, const ca_mgm::intrusive_ptr<_D> & obj ) + { + if ( obj ) + return str << *obj; + return str << std::string("NULL"); + } + /** \relates ca_mgm::intrusive_ptr Stream output. */ + template<class _D> + inline std::ostream & dumpOn( std::ostream & str, const ca_mgm::intrusive_ptr<_D> & obj ) + { + if ( obj ) + return dumpOn( str, *obj ); + return str << std::string("NULL"); + } + ///////////////////////////////////////////////////////////////// +} // namespace std +/////////////////////////////////////////////////////////////////// +/////////////////////////////////////////////////////////////////// +namespace ca_mgm +{ ///////////////////////////////////////////////////////////////// + + /////////////////////////////////////////////////////////////////// + // + // RW_pointer traits + // + /////////////////////////////////////////////////////////////////// + /** + * Don't forgett to provide versions for _Ptr and _constPtr, + * esp. if creation a of temporary is not acceptable (eg. when + * checking the ref count value). + */ + namespace rw_pointer { + + template<class _D> + struct Shared + { + typedef shared_ptr<_D> _Ptr; + typedef shared_ptr<const _D> _constPtr; + /** Check whether pointer is not shared. */ + bool unique( const _constPtr & ptr_r ) + { return !ptr_r || ptr_r.unique(); } + bool unique( const _Ptr & ptr_r ) + { return !ptr_r || ptr_r.unique(); } + /** Return number of references. */ + long use_count( const _constPtr & ptr_r ) const + { return ptr_r.use_count(); } + long use_count( const _Ptr & ptr_r ) const + { return ptr_r.use_count(); } + }; + + template<class _D> + struct Intrusive + { + typedef intrusive_ptr<_D> _Ptr; + typedef intrusive_ptr<const _D> _constPtr; + /** Check whether pointer is not shared. */ + bool unique( const _constPtr & ptr_r ) + { return !ptr_r || (ptr_r->refCount() <= 1); } + bool unique( const _Ptr & ptr_r ) + { return !ptr_r || (ptr_r->refCount() <= 1); } + /** Return number of references. */ + long use_count( const _constPtr & ptr_r ) const + { return ptr_r ? ptr_r->refCount() : 0; } + long use_count( const _Ptr & ptr_r ) const + { return ptr_r ? ptr_r->refCount() : 0; } + }; + + template<class _D> + struct Scoped + { + typedef scoped_ptr<_D> _Ptr; + typedef scoped_ptr<const _D> _constPtr; + /** Check whether pointer is not shared. */ + bool unique( const _constPtr & ptr_r ) + { return true; } + bool unique( const _Ptr & ptr_r ) + { return true; } + /** Return number of references. */ + long use_count( const _constPtr & ptr_r ) const + { return ptr_r ? 1 : 0; } + long use_count( const _Ptr & ptr_r ) const + { return ptr_r ? 1 : 0; } + }; + + } + /////////////////////////////////////////////////////////////////// + + /////////////////////////////////////////////////////////////////// + // + // CLASS NAME : RW_pointer + // + /** Wrapper for \c const correct access via \ref ZYPP_SMART_PTR. + * + * ca_mgm::RW_pointer<tt>\<_D,_Traits></tt> stores a \ref ZYPP_SMART_PTR + * of type \c _Traits::_Ptr, which must be convertible into a <tt>_D *</tt>. + * Pointer style access (via \c -> and \c *) offers a <tt>const _D *</tt> in const + * a context, otherwise a <tt>_D *</tt>. Thus \em RW_ means \em read/write, + * as you get a different type, dependent on whether you're allowed to + * read or write. + * + * Forwarding access from an interface to an implemantation class, an + * RW_pointer prevents const interface methods from accidentally calling + * nonconst implementation methods. + * + * The second template argument defaults to + * <tt>_Traits = rw_pointer::Shared<_D></tt> thus wraping a + * <tt>shared_ptr<_D></tt>. To wrap an <tt>intrusive_ptr<_D></tt> + * use <tt>rw_pointer::Intrusive<_D></tt>. + * + * \see ca_mgm::RWCOW_pointer for 'copy on write' functionality. + * + * \code + * #include "ca_mgm/base/PtrTypes.h" + * + * class Foo + * { + * ... + * private: + * // Implementation class + * struct Impl; + * // Pointer to implementation; actually a shared_ptr<Impl> + * RW_pointer<Impl> _pimpl; + * + * void baa() { _pimpl->... } // is Impl * + * void baa() const { _pimpl->... } // is Impl const * + * }; + * \endcode + */ + template > + struct RW_pointer + { + typedef typename _Traits::_Ptr _Ptr; + typedef typename _Traits::_constPtr _constPtr; + typedef typename _Ptr::unspecified_bool_type unspecified_bool_type; + + explicit + RW_pointer( typename _Ptr::element_type * dptr = 0 ) + : _dptr( dptr ) + {} + + explicit + RW_pointer( _Ptr dptr ) + : _dptr( dptr ) + {} + + void reset() + { _Ptr().swap( _dptr ); } + + void reset( typename _Ptr::element_type * dptr ) + { _Ptr( dptr ).swap( _dptr ); } + + void swap( RW_pointer & rhs ) + { _dptr.swap( rhs._dptr ); } + + void swap( _Ptr & rhs ) + { _dptr.swap( rhs ); } + + operator unspecified_bool_type() const + { return _dptr; } + + const _D & operator*() const + { return *_dptr; }; + + const _D * operator->() const + { return _dptr.get(); } + + const _D * get() const + { return _dptr.get(); } + + _D & operator*() + { return *_dptr; } + + _D * operator->() + { return _dptr.get(); } + + _D * get() + { return _dptr.get(); } + + public: + bool unique() const + { return _Traits().unique( _dptr ); } + + long use_count() const + { return _Traits().use_count( _dptr ); } + + _constPtr getPtr() const + { return _dptr; } + + _Ptr getPtr() + { return _dptr; } + + private: + _Ptr _dptr; + }; + /////////////////////////////////////////////////////////////////// + + /** \relates RW_pointer Stream output. + * + * Print the \c _D object the RW_pointer refers, or \c "NULL" + * if the pointer is \c NULL. + */ + template + inline std::ostream & + operator<<( std::ostream & str, const RW_pointer<_D, _Ptr> & obj ) + { + if ( obj.get() ) + return str << *obj.get(); + return str << std::string("NULL"); + } + + /** \relates RW_pointer */ + template + inline bool + operator==( const RW_pointer<_D, _Ptr> & lhs, const RW_pointer<_D, _Ptr> & rhs ) + { + return( lhs.get() == rhs.get() ); + } + + /** \relates RW_pointer */ + template + inline bool + operator!=( const RW_pointer<_D, _Ptr> & lhs, const RW_pointer<_D, _Ptr> & rhs ) + { + return ! ( lhs == rhs ); + } + + /////////////////////////////////////////////////////////////////// + + /////////////////////////////////////////////////////////////////// + // + // CLASS NAME : RWCOW_pointer + // + /** \ref RW_pointer supporting 'copy on write' functionality. + * + * \em Write access to the underlying object creates a copy, iff + * the object is shared. + * + * See \ref RW_pointer. + */ + template > + struct RWCOW_pointer + { + typedef typename _Traits::_Ptr _Ptr; + typedef typename _Traits::_constPtr _constPtr; + typedef typename _Ptr::unspecified_bool_type unspecified_bool_type; + + explicit + RWCOW_pointer( typename _Ptr::element_type * dptr = 0 ) + : _dptr( dptr ) + {} + + explicit + RWCOW_pointer( _Ptr dptr ) + : _dptr( dptr ) + {} + + void reset() + { _Ptr().swap( _dptr ); } + + void reset( typename _Ptr::element_type * dptr ) + { _Ptr( dptr ).swap( _dptr ); } + + void swap( RWCOW_pointer & rhs ) + { _dptr.swap( rhs._dptr ); } + + void swap( _Ptr & rhs ) + { _dptr.swap( rhs ); } + + operator unspecified_bool_type() const + { return _dptr; } + + const _D & operator*() const + { return *_dptr; }; + + const _D * operator->() const + { return _dptr.get(); } + + const _D * get() const + { return _dptr.get(); } + + _D & operator*() + { assertUnshared(); return *_dptr; } + + _D * operator->() + { assertUnshared(); return _dptr.get(); } + + _D * get() + { assertUnshared(); return _dptr.get(); } + + public: + bool unique() const + { return _Traits().unique( _dptr ); } + + long use_count() const + { return _Traits().use_count( _dptr ); } + + _constPtr getPtr() const + { return _dptr; } + + _Ptr getPtr() + { assertUnshared(); return _dptr; } + + private: + + void assertUnshared() + { + if ( !unique() ) + _Ptr( rwcowClone( _dptr.get() ) ).swap( _dptr ); + } + + private: + _Ptr _dptr; + }; + /////////////////////////////////////////////////////////////////// + + /** \relates RWCOW_pointer Clone the underlying object. + * Calls \a rhs <tt>-\>clone()</tt>. Being defined as a + * function outside \ref RWCOW_pointer allows to overload + * it, in case a specific \a _D does not have <tt>clone()</tt>. + */ + template<class _D> + inline _D * rwcowClone( const _D * rhs ) + { return rhs->clone(); } + + /////////////////////////////////////////////////////////////////// + + /** \relates RWCOW_pointer Stream output. + * + * Print the \c _D object the RWCOW_pointer refers, or \c "NULL" + * if the pointer is \c NULL. + */ + template + inline std::ostream & + operator<<( std::ostream & str, const RWCOW_pointer<_D, _Ptr> & obj ) + { + if ( obj.get() ) + return str << *obj.get(); + return str << std::string("NULL"); + } + + /** \relates RWCOW_pointer */ + template + inline bool + operator==( const RWCOW_pointer<_D, _Ptr> & lhs, const RWCOW_pointer<_D, _Ptr> & rhs ) + { + return( lhs.get() == rhs.get() ); + } + + /** \relates RWCOW_pointer */ + template + inline bool + operator!=( const RWCOW_pointer<_D, _Ptr> & lhs, const RWCOW_pointer<_D, _Ptr> & rhs ) + { + return ! ( lhs == rhs ); + } + + /////////////////////////////////////////////////////////////////// + + /*@}*/ + ///////////////////////////////////////////////////////////////// +} // namespace ca_mgm +/////////////////////////////////////////////////////////////////// + +/** Forward declaration of Ptr types */ +#define DEFINE_PTR_TYPE(NAME) \ +class NAME; \ +extern void intrusive_ptr_add_ref( const NAME * ); \ +extern void intrusive_ptr_release( const NAME * ); \ +typedef ca_mgm::intrusive_ptr<NAME> NAME##_Ptr; \ +typedef ca_mgm::intrusive_ptr<const NAME> NAME##_constPtr; + +/////////////////////////////////////////////////////////////////// +#endif // LIMAL_BASE_PTRTYPES_H -- To unsubscribe, e-mail: limal-commit+unsubscribe@opensuse.org For additional commands, e-mail: limal-commit+help@opensuse.org