nuclear@3: /************************************************************************************
nuclear@3: 
nuclear@3: PublicHeader:   Kernel
nuclear@3: Filename    :   OVR_RefCount.h
nuclear@3: Content     :   Reference counting implementation headers
nuclear@3: Created     :   September 19, 2012
nuclear@3: Notes       : 
nuclear@3: 
nuclear@3: Copyright   :   Copyright 2012 Oculus VR, Inc. All Rights reserved.
nuclear@3: 
nuclear@3: Use of this software is subject to the terms of the Oculus license
nuclear@3: agreement provided at the time of installation or download, or which
nuclear@3: otherwise accompanies this software in either electronic or hard copy form.
nuclear@3: 
nuclear@3: ************************************************************************************/
nuclear@3: 
nuclear@3: #ifndef OVR_RefCount_h
nuclear@3: #define OVR_RefCount_h
nuclear@3: 
nuclear@3: #include "OVR_Types.h"
nuclear@3: #include "OVR_Allocator.h"
nuclear@3: 
nuclear@3: namespace OVR {
nuclear@3: 
nuclear@3: //-----------------------------------------------------------------------------------
nuclear@3: // ***** Reference Counting
nuclear@3: 
nuclear@3: // There are three types of reference counting base classes:
nuclear@3: //
nuclear@3: //  RefCountBase     - Provides thread-safe reference counting (Default).
nuclear@3: //  RefCountBaseNTS  - Non Thread Safe version of reference counting.
nuclear@3: 
nuclear@3: 
nuclear@3: // ***** Declared classes
nuclear@3: 
nuclear@3: template<class C>
nuclear@3: class   RefCountBase;
nuclear@3: template<class C>
nuclear@3: class   RefCountBaseNTS;
nuclear@3: 
nuclear@3: class   RefCountImpl;
nuclear@3: class   RefCountNTSImpl;
nuclear@3: 
nuclear@3: 
nuclear@3: //-----------------------------------------------------------------------------------
nuclear@3: // ***** Implementation For Reference Counting
nuclear@3: 
nuclear@3: // RefCountImplCore holds RefCount value and defines a few utility
nuclear@3: // functions shared by all implementations.
nuclear@3: 
nuclear@3: class RefCountImplCore
nuclear@3: {
nuclear@3: protected:
nuclear@3:     volatile int RefCount;
nuclear@3: 
nuclear@3: public:
nuclear@3:     // RefCountImpl constructor always initializes RefCount to 1 by default.
nuclear@3:     OVR_FORCE_INLINE RefCountImplCore() : RefCount(1) { }
nuclear@3: 
nuclear@3:     // Need virtual destructor
nuclear@3:     // This:    1. Makes sure the right destructor's called.
nuclear@3:     //          2. Makes us have VTable, necessary if we are going to have format needed by InitNewMem()
nuclear@3:     virtual ~RefCountImplCore();
nuclear@3: 
nuclear@3:     // Debug method only.
nuclear@3:     int GetRefCount() const { return RefCount;  }
nuclear@3: 
nuclear@3:     // This logic is used to detect invalid 'delete' calls of reference counted
nuclear@3:     // objects. Direct delete calls are not allowed on them unless they come in
nuclear@3:     // internally from Release.
nuclear@3: #ifdef OVR_BUILD_DEBUG    
nuclear@3:     static void   OVR_CDECL  reportInvalidDelete(void *pmem);
nuclear@3:     inline static void checkInvalidDelete(RefCountImplCore *pmem)
nuclear@3:     {
nuclear@3:         if (pmem->RefCount != 0)
nuclear@3:             reportInvalidDelete(pmem);
nuclear@3:     }
nuclear@3: #else
nuclear@3:     inline static void checkInvalidDelete(RefCountImplCore *) { }
nuclear@3: #endif
nuclear@3: 
nuclear@3:     // Base class ref-count content should not be copied.
nuclear@3:     void operator = (const RefCountImplCore &) { }  
nuclear@3: };
nuclear@3: 
nuclear@3: class RefCountNTSImplCore
nuclear@3: {
nuclear@3: protected:
nuclear@3:     mutable int RefCount;
nuclear@3: 
nuclear@3: public:
nuclear@3:     // RefCountImpl constructor always initializes RefCount to 1 by default.
nuclear@3:     OVR_FORCE_INLINE RefCountNTSImplCore() : RefCount(1) { }
nuclear@3: 
nuclear@3:     // Need virtual destructor
nuclear@3:     // This:    1. Makes sure the right destructor's called.
nuclear@3:     //          2. Makes us have VTable, necessary if we are going to have format needed by InitNewMem()
nuclear@3:     virtual ~RefCountNTSImplCore();
nuclear@3: 
nuclear@3:     // Debug method only.
nuclear@3:     int             GetRefCount() const { return RefCount;  }
nuclear@3: 
nuclear@3:     // This logic is used to detect invalid 'delete' calls of reference counted
nuclear@3:     // objects. Direct delete calls are not allowed on them unless they come in
nuclear@3:     // internally from Release.
nuclear@3: #ifdef OVR_BUILD_DEBUG    
nuclear@3:     static void   OVR_CDECL  reportInvalidDelete(void *pmem);
nuclear@3:     OVR_FORCE_INLINE static void checkInvalidDelete(RefCountNTSImplCore *pmem)
nuclear@3:     {
nuclear@3:         if (pmem->RefCount != 0)
nuclear@3:             reportInvalidDelete(pmem);
nuclear@3:     }
nuclear@3: #else
nuclear@3:     OVR_FORCE_INLINE static void checkInvalidDelete(RefCountNTSImplCore *) { }
nuclear@3: #endif
nuclear@3: 
nuclear@3:     // Base class ref-count content should not be copied.
nuclear@3:     void operator = (const RefCountNTSImplCore &) { }  
nuclear@3: };
nuclear@3: 
nuclear@3: 
nuclear@3: 
nuclear@3: // RefCountImpl provides Thread-Safe implementation of reference counting, so
nuclear@3: // it should be used by default in most places.
nuclear@3: 
nuclear@3: class RefCountImpl : public RefCountImplCore
nuclear@3: {
nuclear@3: public:
nuclear@3:     // Thread-Safe Ref-Count Implementation.
nuclear@3:     void    AddRef();
nuclear@3:     void    Release();   
nuclear@3: };
nuclear@3: 
nuclear@3: // RefCountVImpl provides Thread-Safe implementation of reference counting, plus,
nuclear@3: // virtual AddRef and Release.
nuclear@3: 
nuclear@3: class RefCountVImpl : public RefCountImplCore
nuclear@3: {
nuclear@3: public:
nuclear@3:     // Thread-Safe Ref-Count Implementation.
nuclear@3:     virtual void      AddRef();
nuclear@3:     virtual void      Release();   
nuclear@3: };
nuclear@3: 
nuclear@3: 
nuclear@3: // RefCountImplNTS provides Non-Thread-Safe implementation of reference counting,
nuclear@3: // which is slightly more efficient since it doesn't use atomics.
nuclear@3: 
nuclear@3: class RefCountNTSImpl : public RefCountNTSImplCore
nuclear@3: {
nuclear@3: public:
nuclear@3:     OVR_FORCE_INLINE void    AddRef() const { RefCount++; }
nuclear@3:     void    Release() const;   
nuclear@3: };
nuclear@3: 
nuclear@3: 
nuclear@3: 
nuclear@3: // RefCountBaseStatImpl<> is a common class that adds new/delete override with Stat tracking
nuclear@3: // to the reference counting implementation. Base must be one of the RefCountImpl classes.
nuclear@3: 
nuclear@3: template<class Base>
nuclear@3: class RefCountBaseStatImpl : public Base
nuclear@3: {
nuclear@3: public:
nuclear@3:     RefCountBaseStatImpl() { }
nuclear@3:      
nuclear@3:     // *** Override New and Delete
nuclear@3: 
nuclear@3:     // DOM-IGNORE-BEGIN
nuclear@3:     // Undef new temporarily if it is being redefined
nuclear@3: #ifdef OVR_DEFINE_NEW
nuclear@3: #undef new
nuclear@3: #endif
nuclear@3: 
nuclear@3: #ifdef OVR_BUILD_DEBUG
nuclear@3:     // Custom check used to detect incorrect calls of 'delete' on ref-counted objects.
nuclear@3:     #define OVR_REFCOUNTALLOC_CHECK_DELETE(class_name, p)   \
nuclear@3:         do {if (p) Base::checkInvalidDelete((class_name*)p); } while(0)
nuclear@3: #else
nuclear@3:     #define OVR_REFCOUNTALLOC_CHECK_DELETE(class_name, p)
nuclear@3: #endif
nuclear@3: 
nuclear@3:     // Redefine all new & delete operators.
nuclear@3:     OVR_MEMORY_REDEFINE_NEW_IMPL(Base, OVR_REFCOUNTALLOC_CHECK_DELETE)
nuclear@3: 
nuclear@3: #ifdef OVR_DEFINE_NEW
nuclear@3: #define new OVR_DEFINE_NEW
nuclear@3: #endif
nuclear@3:         // OVR_BUILD_DEFINE_NEW
nuclear@3:         // DOM-IGNORE-END
nuclear@3: };
nuclear@3: 
nuclear@3: 
nuclear@3: 
nuclear@3: //-----------------------------------------------------------------------------------
nuclear@3: // *** End user RefCountBase<> classes
nuclear@3: 
nuclear@3: 
nuclear@3: // RefCountBase is a base class for classes that require thread-safe reference
nuclear@3: // counting; it also overrides the new and delete operators to use MemoryHeap.
nuclear@3: //
nuclear@3: // Reference counted objects start out with RefCount value of 1. Further lifetime
nuclear@3: // management is done through the AddRef() and Release() methods, typically
nuclear@3: // hidden by Ptr<>.
nuclear@3: 
nuclear@3: template<class C>
nuclear@3: class RefCountBase : public RefCountBaseStatImpl<RefCountImpl>
nuclear@3: {
nuclear@3: public:    
nuclear@3:     // Constructor.
nuclear@3:     OVR_FORCE_INLINE RefCountBase() : RefCountBaseStatImpl<RefCountImpl>() { }    
nuclear@3: };
nuclear@3: 
nuclear@3: // RefCountBaseV is the same as RefCountBase but with virtual AddRef/Release
nuclear@3: 
nuclear@3: template<class C>
nuclear@3: class RefCountBaseV : public RefCountBaseStatImpl<RefCountVImpl>
nuclear@3: {
nuclear@3: public:    
nuclear@3:     // Constructor.
nuclear@3:     OVR_FORCE_INLINE RefCountBaseV() : RefCountBaseStatImpl<RefCountVImpl>() { }    
nuclear@3: };
nuclear@3: 
nuclear@3: 
nuclear@3: // RefCountBaseNTS is a base class for classes that require Non-Thread-Safe reference
nuclear@3: // counting; it also overrides the new and delete operators to use MemoryHeap.
nuclear@3: // This class should only be used if all pointers to it are known to be assigned,
nuclear@3: // destroyed and manipulated within one thread.
nuclear@3: //
nuclear@3: // Reference counted objects start out with RefCount value of 1. Further lifetime
nuclear@3: // management is done through the AddRef() and Release() methods, typically
nuclear@3: // hidden by Ptr<>.
nuclear@3: 
nuclear@3: template<class C>
nuclear@3: class RefCountBaseNTS : public RefCountBaseStatImpl<RefCountNTSImpl>
nuclear@3: {
nuclear@3: public:    
nuclear@3:     // Constructor.
nuclear@3:     OVR_FORCE_INLINE RefCountBaseNTS() : RefCountBaseStatImpl<RefCountNTSImpl>() { }    
nuclear@3: };
nuclear@3: 
nuclear@3: //-----------------------------------------------------------------------------------
nuclear@3: // ***** Pickable template pointer
nuclear@3: enum PickType { PickValue };
nuclear@3: 
nuclear@3: template <typename T>
nuclear@3: class Pickable
nuclear@3: {
nuclear@3: public:
nuclear@3:     Pickable() : pV(NULL) {}
nuclear@3:     explicit Pickable(T* p) : pV(p) {}
nuclear@3:     Pickable(T* p, PickType) : pV(p) 
nuclear@3:     {
nuclear@3:         OVR_ASSERT(pV);
nuclear@3:         if (pV)
nuclear@3:             pV->AddRef();
nuclear@3:     }
nuclear@3:     template <typename OT>
nuclear@3:     Pickable(const Pickable<OT>& other) : pV(other.GetPtr()) {}
nuclear@3: 
nuclear@3: public:
nuclear@3:     Pickable& operator =(const Pickable& other)
nuclear@3:     {
nuclear@3:         OVR_ASSERT(pV == NULL);
nuclear@3:         pV = other.pV;
nuclear@3:         // Extra check.
nuclear@3:         //other.pV = NULL;
nuclear@3:         return *this;
nuclear@3:     }
nuclear@3: 
nuclear@3: public:
nuclear@3:     T* GetPtr() const { return pV; }
nuclear@3:     T* operator->() const
nuclear@3:     {
nuclear@3:         return pV;
nuclear@3:     }
nuclear@3:     T& operator*() const
nuclear@3:     {
nuclear@3:         OVR_ASSERT(pV);
nuclear@3:         return *pV;
nuclear@3:     }
nuclear@3: 
nuclear@3: private:
nuclear@3:     T* pV;
nuclear@3: };
nuclear@3: 
nuclear@3: template <typename T>
nuclear@3: OVR_FORCE_INLINE
nuclear@3: Pickable<T> MakePickable(T* p)
nuclear@3: {
nuclear@3:     return Pickable<T>(p);
nuclear@3: }
nuclear@3: 
nuclear@3: //-----------------------------------------------------------------------------------
nuclear@3: // ***** Ref-Counted template pointer
nuclear@3: 
nuclear@3: // Automatically AddRefs and Releases interfaces
nuclear@3: 
nuclear@3: void* ReturnArg0(void* p);
nuclear@3: 
nuclear@3: template<class C>
nuclear@3: class Ptr
nuclear@3: {
nuclear@3: #ifdef OVR_CC_ARM
nuclear@3:     static C* ReturnArg(void* p) { return (C*)ReturnArg0(p); }
nuclear@3: #endif
nuclear@3: 
nuclear@3: protected:
nuclear@3:     C   *pObject;
nuclear@3: 
nuclear@3: public:
nuclear@3: 
nuclear@3:     // Constructors
nuclear@3:     OVR_FORCE_INLINE Ptr() : pObject(0)
nuclear@3:     { }
nuclear@3: #ifdef OVR_CC_ARM
nuclear@3:     OVR_FORCE_INLINE Ptr(C &robj) : pObject(ReturnArg(&robj))
nuclear@3: #else
nuclear@3:     OVR_FORCE_INLINE Ptr(C &robj) : pObject(&robj)
nuclear@3: #endif
nuclear@3:     { }
nuclear@3:     OVR_FORCE_INLINE Ptr(Pickable<C> v) : pObject(v.GetPtr())
nuclear@3:     {
nuclear@3:         // No AddRef() on purpose.
nuclear@3:     }
nuclear@3:     OVR_FORCE_INLINE Ptr(Ptr<C>& other, PickType) : pObject(other.pObject)
nuclear@3:     {
nuclear@3:         other.pObject = NULL;
nuclear@3:         // No AddRef() on purpose.
nuclear@3:     }
nuclear@3:     OVR_FORCE_INLINE Ptr(C *pobj)
nuclear@3:     {
nuclear@3:         if (pobj) pobj->AddRef();   
nuclear@3:         pObject = pobj;
nuclear@3:     }
nuclear@3:     OVR_FORCE_INLINE Ptr(const Ptr<C> &src)
nuclear@3:     {
nuclear@3:         if (src.pObject) src.pObject->AddRef();     
nuclear@3:         pObject = src.pObject;
nuclear@3:     }
nuclear@3: 
nuclear@3:     template<class R>
nuclear@3:     OVR_FORCE_INLINE Ptr(Ptr<R> &src)
nuclear@3:     {
nuclear@3:         if (src) src->AddRef();
nuclear@3:         pObject = src;
nuclear@3:     }
nuclear@3:     template<class R>
nuclear@3:     OVR_FORCE_INLINE Ptr(Pickable<R> v) : pObject(v.GetPtr())
nuclear@3:     {
nuclear@3:         // No AddRef() on purpose.
nuclear@3:     }
nuclear@3: 
nuclear@3:     // Destructor
nuclear@3:     OVR_FORCE_INLINE ~Ptr()
nuclear@3:     {
nuclear@3:         if (pObject) pObject->Release();        
nuclear@3:     }
nuclear@3: 
nuclear@3:     // Compares
nuclear@3:     OVR_FORCE_INLINE bool operator == (const Ptr &other) const       { return pObject == other.pObject; }
nuclear@3:     OVR_FORCE_INLINE bool operator != (const Ptr &other) const       { return pObject != other.pObject; }
nuclear@3: 
nuclear@3:     OVR_FORCE_INLINE bool operator == (C *pother) const              { return pObject == pother; }
nuclear@3:     OVR_FORCE_INLINE bool operator != (C *pother) const              { return pObject != pother; }
nuclear@3: 
nuclear@3: 
nuclear@3:     OVR_FORCE_INLINE bool operator < (const Ptr &other) const       { return pObject < other.pObject; }
nuclear@3: 
nuclear@3:     // Assignment
nuclear@3:     template<class R>
nuclear@3:     OVR_FORCE_INLINE const Ptr<C>& operator = (const Ptr<R> &src)
nuclear@3:     {
nuclear@3:         if (src) src->AddRef();
nuclear@3:         if (pObject) pObject->Release();        
nuclear@3:         pObject = src;
nuclear@3:         return *this;
nuclear@3:     }   
nuclear@3:     // Specialization
nuclear@3:     OVR_FORCE_INLINE const Ptr<C>& operator = (const Ptr<C> &src)
nuclear@3:     {
nuclear@3:         if (src) src->AddRef();
nuclear@3:         if (pObject) pObject->Release();        
nuclear@3:         pObject = src;
nuclear@3:         return *this;
nuclear@3:     }   
nuclear@3:     
nuclear@3:     OVR_FORCE_INLINE const Ptr<C>& operator = (C *psrc)
nuclear@3:     {
nuclear@3:         if (psrc) psrc->AddRef();
nuclear@3:         if (pObject) pObject->Release();        
nuclear@3:         pObject = psrc;
nuclear@3:         return *this;
nuclear@3:     }   
nuclear@3:     OVR_FORCE_INLINE const Ptr<C>& operator = (C &src)
nuclear@3:     {       
nuclear@3:         if (pObject) pObject->Release();        
nuclear@3:         pObject = &src;
nuclear@3:         return *this;
nuclear@3:     }
nuclear@3:     OVR_FORCE_INLINE Ptr<C>& operator = (Pickable<C> src)
nuclear@3:     {
nuclear@3:         return Pick(src);
nuclear@3:     }
nuclear@3:     template<class R>
nuclear@3:     OVR_FORCE_INLINE Ptr<C>& operator = (Pickable<R> src)
nuclear@3:     {
nuclear@3:         return Pick(src);
nuclear@3:     }
nuclear@3:     
nuclear@3:     // Set Assignment
nuclear@3:     template<class R>
nuclear@3:     OVR_FORCE_INLINE Ptr<C>& SetPtr(const Ptr<R> &src)
nuclear@3:     {
nuclear@3:         if (src) src->AddRef();
nuclear@3:         if (pObject) pObject->Release();
nuclear@3:         pObject = src;
nuclear@3:         return *this;
nuclear@3:     }
nuclear@3:     // Specialization
nuclear@3:     OVR_FORCE_INLINE Ptr<C>& SetPtr(const Ptr<C> &src)
nuclear@3:     {
nuclear@3:         if (src) src->AddRef();
nuclear@3:         if (pObject) pObject->Release();
nuclear@3:         pObject = src;
nuclear@3:         return *this;
nuclear@3:     }   
nuclear@3:     
nuclear@3:     OVR_FORCE_INLINE Ptr<C>& SetPtr(C *psrc)
nuclear@3:     {
nuclear@3:         if (psrc) psrc->AddRef();
nuclear@3:         if (pObject) pObject->Release();
nuclear@3:         pObject = psrc;
nuclear@3:         return *this;
nuclear@3:     }   
nuclear@3:     OVR_FORCE_INLINE Ptr<C>& SetPtr(C &src)
nuclear@3:     {       
nuclear@3:         if (pObject) pObject->Release();
nuclear@3:         pObject = &src;
nuclear@3:         return *this;
nuclear@3:     }
nuclear@3:     OVR_FORCE_INLINE Ptr<C>& SetPtr(Pickable<C> src)
nuclear@3:     {       
nuclear@3:         return Pick(src);
nuclear@3:     }
nuclear@3: 
nuclear@3:     // Nulls ref-counted pointer without decrement
nuclear@3:     OVR_FORCE_INLINE void    NullWithoutRelease()    
nuclear@3:     { 
nuclear@3:         pObject = 0;    
nuclear@3:     }
nuclear@3: 
nuclear@3:     // Clears the pointer to the object
nuclear@3:     OVR_FORCE_INLINE void    Clear()
nuclear@3:     {
nuclear@3:         if (pObject) pObject->Release();
nuclear@3:         pObject = 0;
nuclear@3:     }
nuclear@3: 
nuclear@3:     // Obtain pointer reference directly, for D3D interfaces
nuclear@3:     OVR_FORCE_INLINE C*& GetRawRef()                 { return pObject; }
nuclear@3: 
nuclear@3:     // Access Operators
nuclear@3:     OVR_FORCE_INLINE C* GetPtr() const               { return pObject; }
nuclear@3:     OVR_FORCE_INLINE C& operator * () const          { return *pObject; }
nuclear@3:     OVR_FORCE_INLINE C* operator -> ()  const        { return pObject; }
nuclear@3:     // Conversion                   
nuclear@3:     OVR_FORCE_INLINE operator C* () const            { return pObject; }
nuclear@3: 
nuclear@3:     // Pickers.
nuclear@3: 
nuclear@3:     // Pick a value.
nuclear@3:     OVR_FORCE_INLINE Ptr<C>& Pick(Ptr<C>& other)
nuclear@3:     {
nuclear@3:         if (&other != this)
nuclear@3:         {
nuclear@3:             if (pObject) pObject->Release();
nuclear@3:             pObject = other.pObject;
nuclear@3:             other.pObject = 0;
nuclear@3:         }
nuclear@3: 
nuclear@3:         return *this;
nuclear@3:     }
nuclear@3: 
nuclear@3:     OVR_FORCE_INLINE Ptr<C>& Pick(Pickable<C> v)
nuclear@3:     {
nuclear@3:         if (v.GetPtr() != pObject)
nuclear@3:         {
nuclear@3:             if (pObject) pObject->Release();
nuclear@3:             pObject = v.GetPtr();
nuclear@3:         }
nuclear@3: 
nuclear@3:         return *this;
nuclear@3:     }
nuclear@3: 
nuclear@3:     template<class R>
nuclear@3:     OVR_FORCE_INLINE Ptr<C>& Pick(Pickable<R> v)
nuclear@3:     {
nuclear@3:         if (v.GetPtr() != pObject)
nuclear@3:         {
nuclear@3:             if (pObject) pObject->Release();
nuclear@3:             pObject = v.GetPtr();
nuclear@3:         }
nuclear@3: 
nuclear@3:         return *this;
nuclear@3:     }
nuclear@3: 
nuclear@3:     OVR_FORCE_INLINE Ptr<C>& Pick(C* p)
nuclear@3:     {
nuclear@3:         if (p != pObject)
nuclear@3:         {
nuclear@3:             if (pObject) pObject->Release();
nuclear@3:             pObject = p;
nuclear@3:         }
nuclear@3: 
nuclear@3:         return *this;
nuclear@3:     }
nuclear@3: };
nuclear@3: 
nuclear@3: } // OVR
nuclear@3: 
nuclear@3: #endif