CObject.h

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/* +---------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)               |
   |                          http://www.mrpt.org/                             |
   |                                                                           |
   | Copyright (c) 2005-2017, Individual contributors, see AUTHORS file        |
   | See: http://www.mrpt.org/Authors - All rights reserved.                   |
   | Released under BSD License. See details in http://www.mrpt.org/License    |
   +---------------------------------------------------------------------------+ */
#ifndef  MRPT_COBJECT_H
#define  MRPT_COBJECT_H

#include <mrpt/system/memory.h>
#include <mrpt/utils/safe_pointers.h>
#include <vector>

#include <memory> // shared_ptr

namespace mrpt
{
        namespace utils
        {
                /** @name RTTI classes and functions
                    @{ */

                class BASE_IMPEXP CObject;

                /** A smart pointer to a CObject object
                  * \note Declared as a class instead of a typedef to avoid multiple defined symbols when linking dynamic libs.
                  * \ingroup mrpt_base_grp
                  */
                struct BASE_IMPEXP CObjectPtr;

                /** A structure that holds runtime class type information. Use CLASS_ID(<class_name>) to get a reference to the class_name's TRuntimeClassId descriptor.
                  * \ingroup mrpt_base_grp
                  */
                struct BASE_IMPEXP TRuntimeClassId
                {
                        const char* className;
                        /** Create an object of the related class, or NULL if it is virtual. */
                        mrpt::utils::CObject*                   (*ptrCreateObject)();
                        /** Gets the base class runtime id. */
                        const TRuntimeClassId*          (*getBaseClass)();

                        // Operations
                        mrpt::utils::CObject*           createObject() const;
                        bool    derivedFrom(const TRuntimeClassId* pBaseClass) const;
                        bool    derivedFrom(const char* pBaseClass_name) const;

                };

                /** A wrapper class for a "TRuntimeClassId *", well-defined with respect to copy operators and constructors. \ingroup mrpt_base_grp
                  */
                typedef safe_ptr<TRuntimeClassId> TRuntimeClassIdPtr;

                /** Register a class into the MRPT internal list of "CSerializable" descendents.
                  *  Used internally in the macros DEFINE_SERIALIZABLE, etc...
                  * \sa getAllRegisteredClasses
                  */
                void BASE_IMPEXP registerClass(const mrpt::utils::TRuntimeClassId* pNewClass);

                /** Mostly for internal use within mrpt sources, to handle exceptional cases with multiple serialization names for backward compatibility (CMultiMetricMaps, CImage,...)
                  */
                void  BASE_IMPEXP registerClassCustomName(const char*customName, const TRuntimeClassId* pNewClass);

                /** Returns a list with all the classes registered in the system through mrpt::utils::registerClass.
                  * \sa registerClass, findRegisteredClass
                  */
                std::vector<const mrpt::utils::TRuntimeClassId*> BASE_IMPEXP getAllRegisteredClasses();

                /** Like getAllRegisteredClasses(), but filters the list to only include children clases of a given base one.
                  * \sa getAllRegisteredClasses(), getAllRegisteredClassesChildrenOf()  */
                std::vector<const TRuntimeClassId*> BASE_IMPEXP getAllRegisteredClassesChildrenOf(const TRuntimeClassId* parent_id);

                /** Return info about a given class by its name, or NULL if the class is not registered
                  * \sa registerClass, getAllRegisteredClasses
                  */
                const TRuntimeClassId BASE_IMPEXP * findRegisteredClass(const std::string &className);


                /** Access to runtime class ID for a defined class name.
                  */
                #define CLASS_ID(class_name) static_cast<const mrpt::utils::TRuntimeClassId*>(&class_name::class##class_name)

                /** Access to runtime class ID for a defined class name.
                  */
                #define CLASS_ID_NAMESPACE(class_name,namespaceName) static_cast<const mrpt::utils::TRuntimeClassId*>(&namespaceName::class_name::class##class_name)

                /** Access to runtime class ID for a defined template class name.
                  */
                #define CLASS_ID_TEMPLATE(class_name,T) static_cast<const mrpt::utils::TRuntimeClassId*>(& template <class T> class_name<T>::class##class_name)

                /** Evaluates to true if the given pointer to an object (derived from mrpt::utils::CSerializable) is of the given class. */
                #define IS_CLASS( ptrObj, class_name )  ((ptrObj)->GetRuntimeClass()==CLASS_ID(class_name))

                /** Evaluates to true if the given pointer to an object (derived from mrpt::utils::CSerializable) is an instance of the given class or any of its derived classes. */
                #define IS_DERIVED( ptrObj, class_name )  ((ptrObj)->GetRuntimeClass()->derivedFrom(CLASS_ID(class_name)))

                /** Auxiliary structure used for CObject-based RTTI. \ingroup mrpt_base_grp */
                struct BASE_IMPEXP CLASSINIT
                {
                        CLASSINIT(const mrpt::utils::TRuntimeClassId* pNewClass)
                        {
                                registerClass(pNewClass);
                        }
                };


                /** The virtual base class of all MRPT classes with a unified RTTI system.
                 *   For each class named <code>CMyClass</code>, a new type named <code>CMyClassPtr</code> will be created as a smart pointer suitable for
                 *    keeping referencing count smart pointers to objects of that class. By default the base class of all these smart pointers is CObjectPtr.
                 * \sa  mrpt::utils::CSerializable \ingroup mrpt_base_grp
                 */
                class BASE_IMPEXP CObject
                {
                protected:
                        static  mrpt::utils::TRuntimeClassId* _GetBaseClass();
                public:
                        static const mrpt::utils::TRuntimeClassId classCObject;

                        /** Returns information about the class of an object in runtime. */
                        virtual const mrpt::utils::TRuntimeClassId* GetRuntimeClass() const
                        {
                                return CLASS_ID(CObject);
                        }

                        /** Returns a copy of the object, indepently of its class. */
                        virtual CObject *duplicate() const = 0;

                        /** Returns a copy of the object, indepently of its class, as a smart pointer (the newly created object will exist as long as any copy of this smart pointer). */
                        inline mrpt::utils::CObjectPtr duplicateGetSmartPtr() const;

                        /** Cloning interface for smart pointers */
                        inline CObject *clone() const { return duplicate(); }

                        virtual ~CObject() {  }

                }; // End of class def.

                struct BASE_IMPEXP CObjectPtr
                {
                        std::shared_ptr<CObject> m_ptr;
                        inline CObjectPtr() {}
                        explicit inline CObjectPtr(CObject* data) : m_ptr(data) { }
                        virtual CObject * pointer() { return m_ptr.get(); }
                        virtual CObject * get() { return m_ptr.get(); }
                        virtual const CObject * pointer() const { return m_ptr.get(); }
                        virtual const CObject * get() const { return m_ptr.get(); }
                        virtual CObject* operator ->(void) { return m_ptr.get(); }
                        virtual const CObject* operator ->(void) const { return m_ptr.get(); }
                        virtual CObject& operator *(void) { ASSERT_(m_ptr); return *m_ptr.get(); }
                        virtual const CObject& operator *(void) const { ASSERT_(m_ptr); return *m_ptr.get(); }
                        void clear() { m_ptr.reset(); }
                        bool operator !() const { return !m_ptr.operator bool();  }
                        operator bool() const { return m_ptr.operator bool(); }
                        void make_unique() { if (!m_ptr) return; m_ptr.reset(m_ptr.get()->clone()); }
                        bool present() const { return m_ptr.get()!=NULL; }
                        void set(CObject* p) { m_ptr.reset(p); }
                        void reset(CObject* p=NULL) { m_ptr.reset(p); }
                        void clear_unique() { m_ptr.reset(); }
                };

                inline mrpt::utils::CObjectPtr mrpt::utils::CObject::duplicateGetSmartPtr() const { return mrpt::utils::CObjectPtr(this->duplicate()); }


                /** Just like DEFINE_MRPT_OBJECT but with DLL export/import linkage keywords. Note: The replication of macro arguments is to avoid errors with empty macro arguments */
#define DEFINE_MRPT_OBJECT_CUSTOM_LINKAGE(class_name, _STATIC_LINKAGE_, _VIRTUAL_LINKAGE_) \
                        /*! @name RTTI stuff  */ \
                        /*! @{  */ \
                protected: \
                        _STATIC_LINKAGE_ const mrpt::utils::TRuntimeClassId* _GetBaseClass(); \
                        _STATIC_LINKAGE_ mrpt::utils::CLASSINIT _init_##class_name;\
                public: \
                        /*! A typedef for the associated smart pointer */ \
                        typedef class_name##Ptr Ptr; \
                        typedef class_name##Ptr ConstPtr; \
                        _STATIC_LINKAGE_ mrpt::utils::TRuntimeClassId  class##class_name; \
                        _STATIC_LINKAGE_ const mrpt::utils::TRuntimeClassId *classinfo; \
                        _VIRTUAL_LINKAGE_ const mrpt::utils::TRuntimeClassId* GetRuntimeClass() const MRPT_OVERRIDE; \
                        _STATIC_LINKAGE_ mrpt::utils::CObject* CreateObject(); \
                        _STATIC_LINKAGE_ class_name##Ptr Create(); \
                        _VIRTUAL_LINKAGE_ mrpt::utils::CObject *duplicate() const MRPT_OVERRIDE; \
                        /*! @} */ \
                public: \
                        MRPT_MAKE_ALIGNED_OPERATOR_NEW \

                /** This declaration must be inserted in all CObject classes definition, within the class declaration. */
#define DEFINE_MRPT_OBJECT(class_name) \
                        DEFINE_MRPT_OBJECT_CUSTOM_LINKAGE(class_name, static /*none*/, virtual /*none*/)

                // This macro is a workaround to avoid possibly empty arguments to MACROS (when _LINKAGE_ evals to nothing...)
#define DEFINE_MRPT_OBJECT_PRE_CUSTOM_BASE_LINKAGE(class_name, base_name, _LINKAGE_ )  DEFINE_MRPT_OBJECT_PRE_CUSTOM_BASE_LINKAGE2(class_name, base_name, _LINKAGE_ class_name)
#define DEFINE_MRPT_OBJECT_POST_CUSTOM_BASE_LINKAGE(class_name, base_name, _LINKAGE_ ) DEFINE_MRPT_OBJECT_POST_CUSTOM_BASE_LINKAGE2(class_name, base_name, _LINKAGE_ class_name)

// Use this one when there is NO import/export macro:
#define DEFINE_MRPT_OBJECT_PRE_CUSTOM_BASE_NO_LINKAGE(class_name, base_name) DEFINE_MRPT_OBJECT_PRE_CUSTOM_BASE_LINKAGE2(class_name, base_name, class_name)
#define DEFINE_MRPT_OBJECT_POST_CUSTOM_BASE_NO_LINKAGE(class_name, base_name) DEFINE_MRPT_OBJECT_POST_CUSTOM_BASE_LINKAGE2(class_name, base_name, class_name)

/**  This declaration must be inserted in all CObject classes definition, before the class declaration.  */
#define DEFINE_MRPT_OBJECT_PRE_CUSTOM_BASE_LINKAGE2(class_name, base_name, class_name_LINKAGE_ ) \
                        class  class_name_LINKAGE_; \
                        struct class_name_LINKAGE_##Ptr;

/**  This declaration must be inserted in all CObject classes definition, after the class declaration.  */
#define DEFINE_MRPT_OBJECT_POST_CUSTOM_BASE_LINKAGE2(class_name, base_name, class_name_LINKAGE_ ) \
                        /*! The smart pointer type for the associated class */ \
                        struct class_name_LINKAGE_##Ptr : public base_name##Ptr \
                        { \
                                typedef class_name value_type; \
                                class_name##Ptr() { } \
                                explicit class_name##Ptr(class_name* p) : base_name##Ptr(p) { } \
                                class_name##Ptr(const mrpt::utils::CObjectPtr &p) { m_ptr = p.m_ptr; } \
                                /*! Return the internal plain C++ pointer */ \
                                class_name * pointer() { return dynamic_cast<class_name*>(m_ptr.get()); } \
                                class_name * get() { return dynamic_cast<class_name*>(m_ptr.get()); } \
                                /*! Return the internal plain C++ pointer (const) */ \
                                const class_name * pointer() const { return dynamic_cast<const class_name*>(m_ptr.get()); } \
                                const class_name * get() const { return dynamic_cast<const class_name*>(m_ptr.get()); } \
                                class_name* operator ->(void) { return dynamic_cast<class_name*>(m_ptr.get()); } \
                                const class_name* operator ->(void) const { return dynamic_cast<const class_name*>(m_ptr.get()); } \
                                class_name& operator *(void) { ASSERT_(m_ptr); return *dynamic_cast<class_name*>(m_ptr.get()); } \
                                const class_name& operator *(void) const { ASSERT_(m_ptr); return *dynamic_cast<const class_name*>(m_ptr.get()); } \
                        };


                // This macro is a workaround to avoid possibly empty arguments to MACROS (when _LINKAGE_ evals to nothing...)
                #define DEFINE_MRPT_OBJECT_PRE_CUSTOM_LINKAGE(class_name,_LINKAGE_)  DEFINE_MRPT_OBJECT_PRE_CUSTOM_LINKAGE2(class_name, _LINKAGE_ class_name)
                #define DEFINE_MRPT_OBJECT_POST_CUSTOM_LINKAGE(class_name,_LINKAGE_) DEFINE_MRPT_OBJECT_POST_CUSTOM_LINKAGE2(class_name, _LINKAGE_ class_name)

                // Use this macro when there is NO export/import macro:
                #define DEFINE_MRPT_OBJECT_PRE_NO_LINKAGE(class_name) DEFINE_MRPT_OBJECT_PRE_CUSTOM_LINKAGE2(class_name, class_name)
                #define DEFINE_MRPT_OBJECT_POST_NO_LINKAGE(class_name) DEFINE_MRPT_OBJECT_POST_CUSTOM_LINKAGE2(class_name, class_name)

                // This one is almost identical to the one above, but without a member:
                /**  This declaration must be inserted in all CObject classes definition, before the class declaration. */
                #define DEFINE_MRPT_OBJECT_PRE_CUSTOM_LINKAGE2(class_name,class_name_LINKAGE_) \
                        struct class_name_LINKAGE_##Ptr;

                /**  This declaration must be inserted in all CObject classes definition, after the class declaration. */
                #define DEFINE_MRPT_OBJECT_POST_CUSTOM_LINKAGE2(class_name,class_name_LINKAGE_) \
                        /*! The smart pointer type for the associated class */ \
                        struct class_name_LINKAGE_##Ptr : public mrpt::utils::CObjectPtr \
                        { \
                                inline class_name##Ptr() : mrpt::utils::CObjectPtr(static_cast<mrpt::utils::CObject*>(NULL)) { } \
                                inline explicit class_name##Ptr(class_name* p) : mrpt::utils::CObjectPtr( static_cast<mrpt::utils::CObject*>(p) ) { } \
                                inline explicit class_name##Ptr(const mrpt::utils::CObjectPtr & p) : mrpt::utils::CObjectPtr(p) { ASSERTMSG_( p->GetRuntimeClass()->derivedFrom(#class_name),::mrpt::format("Wrong typecasting of smart pointers: %s -> %s",p->GetRuntimeClass()->className, #class_name) )  } \
                                /*! Return the internal plain C++ pointer */ \
                                inline class_name * pointer() { return dynamic_cast<class_name*>(mrpt::utils::CObjectPtr::pointer()); } \
                                /*! Return the internal plain C++ pointer (const) */ \
                                inline const class_name * pointer() const { return dynamic_cast<const class_name*>(mrpt::utils::CObjectPtr::pointer()); } \
                                inline class_name* operator ->(void) { return dynamic_cast<class_name*>( mrpt::utils::CObjectPtr::operator ->() ); } \
                                inline const class_name* operator ->(void) const { return dynamic_cast<const class_name*>( mrpt::utils::CObjectPtr::operator ->() ); } \
                                inline class_name& operator *(void) { return *dynamic_cast<class_name*>( mrpt::utils::CObjectPtr::operator ->() ); } \
                                inline const class_name& operator *(void) const { return *dynamic_cast<const class_name*>( mrpt::utils::CObjectPtr::operator ->() ); } \
                        };

                /**  This declaration must be inserted in all CObject classes definition, before the class declaration.
                  */
                #define DEFINE_MRPT_OBJECT_PRE_CUSTOM_BASE(class_name, base_name) \
                        DEFINE_MRPT_OBJECT_PRE_CUSTOM_BASE_LINKAGE(class_name, base_name, BASE_IMPEXP )

                /**  This declaration must be inserted in all CObject classes definition, before the class declaration.
                  */
                #define DEFINE_MRPT_OBJECT_PRE(class_name)  DEFINE_MRPT_OBJECT_PRE_CUSTOM_LINKAGE(class_name, BASE_IMPEXP )  // This macro is valid for classes within mrpt-base only.
                #define DEFINE_MRPT_OBJECT_POST(class_name) DEFINE_MRPT_OBJECT_POST_CUSTOM_LINKAGE(class_name, BASE_IMPEXP )  // This macro is valid for classes within mrpt-base only.

                /** This must be inserted in all CObject classes implementation files
                  */
                #define IMPLEMENTS_MRPT_OBJECT(class_name, base,NameSpace) \
                        mrpt::utils::CObject* NameSpace::class_name::CreateObject() \
                                { return static_cast<mrpt::utils::CObject*>( new NameSpace::class_name ); } \
                        NameSpace::class_name##Ptr NameSpace::class_name::Create() \
                                { return NameSpace::class_name##Ptr( new NameSpace::class_name ); } \
                        const mrpt::utils::TRuntimeClassId* NameSpace::class_name::_GetBaseClass() \
                                { return CLASS_ID(base); } \
                        mrpt::utils::TRuntimeClassId NameSpace::class_name::class##class_name = { \
                                #class_name, NameSpace::class_name::CreateObject, &class_name::_GetBaseClass }; \
                        const mrpt::utils::TRuntimeClassId *NameSpace::class_name::classinfo = & NameSpace::class_name::class##class_name; \
                        const mrpt::utils::TRuntimeClassId* NameSpace::class_name::GetRuntimeClass() const \
                        { return CLASS_ID_NAMESPACE(class_name,NameSpace); } \
                        mrpt::utils::CLASSINIT NameSpace::class_name::_init_##class_name(CLASS_ID(base)); \
                        mrpt::utils::CObject * NameSpace::class_name::duplicate() const \
                        { return static_cast<mrpt::utils::CObject*>( new NameSpace::class_name(*this) ); }


                /** This declaration must be inserted in virtual CSerializable classes definition:
                  */
                #define DEFINE_VIRTUAL_MRPT_OBJECT(class_name) \
                /*! @name RTTI stuff  */ \
                /*! @{  */ \
                protected: \
                        static const mrpt::utils::TRuntimeClassId* _GetBaseClass(); \
                public: \
                        static const mrpt::utils::TRuntimeClassId class##class_name; \
                        virtual const mrpt::utils::TRuntimeClassId* GetRuntimeClass() const MRPT_OVERRIDE; \
                        friend class mrpt::utils::CStream; \
                        typedef class_name##Ptr Ptr; \
                        typedef class_name##Ptr ConstPtr; \
                /*! @}  */ \

                /** This must be inserted as implementation of some required members for
                  *  virtual CSerializable classes:
                  */
                #define IMPLEMENTS_VIRTUAL_MRPT_OBJECT(class_name, base_class_name,NameSpace) \
                        const mrpt::utils::TRuntimeClassId* class_name::_GetBaseClass() \
                                { return CLASS_ID(base_class_name); } \
                        const mrpt::utils::TRuntimeClassId class_name::class##class_name = { \
                                #class_name, NULL, &class_name::_GetBaseClass }; \
                        const mrpt::utils::TRuntimeClassId* class_name::GetRuntimeClass() const \
                                { return CLASS_ID(class_name); }

                /** @}  */   // end of RTTI

                /** Register all pending classes - to be called just before de-serializing an object, for example.
                  * After calling this method, pending_class_registers_modified is set to false until pending_class_registers() is invoked.
                  */
                void BASE_IMPEXP registerAllPendingClasses();

        } // End of namespace

/** Converts a smart pointer Base::Ptr to Derived::Ptr, in a way compatible
* with MRPT >=1.5.4 and MRPT 2.x series.
* \ingroup mrpt_base_grp
*/
template <typename CAST_TO>
struct ptr_cast
{
        template <typename CAST_FROM_PTR>
        static typename CAST_TO::Ptr from(const CAST_FROM_PTR &ptr)
        {
                return typename CAST_TO::Ptr(ptr);
        }
};

} // End of namespace

#endif