intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 429 insertions, 0 deletions

diff --git a/util/ysafeptr.h b/util/ysafeptr.h
new file mode 100644
index 0000000000..af7dfd4bed
--- /dev/null
+++ b/util/ysafeptr.h
@@ -0,0 +1,429 @@
+#pragma once
+
+#include <stddef.h>
+#include <util/system/yassert.h>
+#include <util/system/defaults.h>
+#include <util/system/tls.h>
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+//   There are different templates of pointers:
+//     1. Simple pointers.
+//     2. TPtr with refereces.
+//     3. TObj/TMObj with ownership. After destruction of a TObj the object it referenced to is
+//        cleaned up and marked as non valid. Similarly does TMobj organizing the parallel ownership
+//        of an object.
+//
+//   Limitations:
+//     1. It may be necessary to use BASIC_REGISTER_CLASS() in .cpp files to be able to use a
+//        pointer to a forward declared class.
+//     2. It's prohibited to override the 'new' operator, since the standard 'delete' will be used
+//        for destruction of objects (because of 'delete this').
+////////////////////////////////////////////////////////////////////////////////////////////////////
+
+#if defined(_MSC_VER) && defined(_DEBUG)
+    #include <util/system/winint.h>
+    #define CHECK_YPTR2
+#endif
+
+struct IBinSaver;
+
+class IObjectBase {
+private:
+#ifdef CHECK_YPTR2
+    static Y_POD_THREAD(bool) DisableThreadCheck;
+    void CheckThreadId() {
+        if (dwThreadId == 0)
+            dwThreadId = GetCurrentThreadId();
+        else
+            Y_ASSERT(dwThreadId == GetCurrentThreadId() || DisableThreadCheck);
+    }
+    void AddRef() {
+        CheckThreadId();
+        ++RefData;
+    }
+    void AddObj(int nRef) {
+        CheckThreadId();
+        ObjData += nRef;
+    }
+#else
+    void CheckThreadId() {
+    }
+    void AddRef() {
+        ++RefData;
+    }
+    void AddObj(int nRef) {
+        ObjData += nRef;
+    }
+#endif
+    void ReleaseRefComplete();
+    void ReleaseObjComplete(int nMask);
+    void DecRef() {
+        CheckThreadId();
+        --RefData;
+    }
+    void DecObj(int nRef) {
+        CheckThreadId();
+        ObjData -= nRef;
+    }
+    void ReleaseRef() {
+        CheckThreadId();
+        --RefData;
+        if (RefData == 0)
+            ReleaseRefComplete();
+    }
+    void ReleaseObj(int nRef, int nMask) {
+        CheckThreadId();
+        ObjData -= nRef;
+        if ((ObjData & nMask) == 0)
+            ReleaseObjComplete(nMask);
+    }
+
+protected:
+#ifdef CHECK_YPTR2
+    DWORD dwThreadId;
+#endif
+    ui32 ObjData;
+    ui32 RefData;
+    // function should clear contents of object, easy to implement via consequent calls to
+    // destructor and constructor, this function should not be called directly, use Clear()
+    virtual void DestroyContents() = 0;
+    virtual ~IObjectBase() = default;
+    inline void CopyValidFlag(const IObjectBase& a) {
+        ObjData &= 0x7fffffff;
+        ObjData |= a.ObjData & 0x80000000;
+    }
+
+public:
+    IObjectBase()
+        : ObjData(0)
+        , RefData(0)
+    {
+#ifdef CHECK_YPTR2
+        dwThreadId = 0;
+#endif
+    }
+    // do not copy refcount when copy object
+    IObjectBase(const IObjectBase& a)
+        : ObjData(0)
+        , RefData(0)
+    {
+#ifdef CHECK_YPTR2
+        dwThreadId = 0;
+#endif
+        CopyValidFlag(a);
+    }
+    IObjectBase& operator=(const IObjectBase& a) {
+        CopyValidFlag(a);
+        return *this;
+    }
+#ifdef CHECK_YPTR2
+    static void SetThreadCheckMode(bool val) {
+        DisableThreadCheck = !val;
+    }
+    void ResetThreadId() {
+        Y_ASSERT(RefData == 0 && ObjData == 0); // can reset thread check only for ref free objects
+        dwThreadId = 0;
+    }
+#else
+    static void SetThreadCheckMode(bool) {
+    }
+    void ResetThreadId() {
+    }
+#endif
+
+    // class name of derived class
+    virtual const char* GetClassName() const = 0;
+
+    ui32 IsRefInvalid() const {
+        return (ObjData & 0x80000000);
+    }
+    ui32 IsRefValid() const {
+        return !IsRefInvalid();
+    }
+    // reset data in class to default values, saves RefCount from destruction
+    void Clear() {
+        AddRef();
+        DestroyContents();
+        DecRef();
+    }
+
+    virtual int operator&(IBinSaver&) {
+        return 0;
+    }
+
+    struct TRefO {
+        void AddRef(IObjectBase* pObj) {
+            pObj->AddObj(1);
+        }
+        void DecRef(IObjectBase* pObj) {
+            pObj->DecObj(1);
+        }
+        void Release(IObjectBase* pObj) {
+            pObj->ReleaseObj(1, 0x000fffff);
+        }
+    };
+    struct TRefM {
+        void AddRef(IObjectBase* pObj) {
+            pObj->AddObj(0x100000);
+        }
+        void DecRef(IObjectBase* pObj) {
+            pObj->DecObj(0x100000);
+        }
+        void Release(IObjectBase* pObj) {
+            pObj->ReleaseObj(0x100000, 0x3ff00000);
+        }
+    };
+    struct TRef {
+        void AddRef(IObjectBase* pObj) {
+            pObj->AddRef();
+        }
+        void DecRef(IObjectBase* pObj) {
+            pObj->DecRef();
+        }
+        void Release(IObjectBase* pObj) {
+            pObj->ReleaseRef();
+        }
+    };
+    friend struct IObjectBase::TRef;
+    friend struct IObjectBase::TRefO;
+    friend struct IObjectBase::TRefM;
+};
+////////////////////////////////////////////////////////////////////////////////////////////////////
+// macro that helps to create neccessary members for proper operation of refcount system
+// if class needs special destructor, use CFundament
+#define OBJECT_METHODS(classname)                                 \
+public:                                                           \
+    virtual const char* GetClassName() const override {           \
+        return #classname;                                        \
+    }                                                             \
+    static IObjectBase* NewSaveLoadNullItem() {                   \
+        return new classname();                                   \
+    }                                                             \
+                                                                  \
+protected:                                                        \
+    virtual void DestroyContents() override {                     \
+        this->~classname();                                       \
+        int nHoldRefs = this->RefData, nHoldObjs = this->ObjData; \
+        new (this) classname();                                   \
+        this->RefData += nHoldRefs;                               \
+        this->ObjData += nHoldObjs;                               \
+    }                                                             \
+                                                                  \
+private:
+#define OBJECT_NOCOPY_METHODS(classname) OBJECT_METHODS(classname)
+#define BASIC_REGISTER_CLASS(classname)                                              \
+    Y_PRAGMA_DIAGNOSTIC_PUSH                                                         \
+    Y_PRAGMA_NO_UNUSED_FUNCTION                                                      \
+    template <>                                                                      \
+    IObjectBase* CastToObjectBaseImpl<classname>(classname * p, void*) {             \
+        return p;                                                                    \
+    }                                                                                \
+    template <>                                                                      \
+    classname* CastToUserObjectImpl<classname>(IObjectBase * p, classname*, void*) { \
+        return dynamic_cast<classname*>(p);                                          \
+    }                                                                                \
+    Y_PRAGMA_DIAGNOSTIC_POP
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+template <class TUserObj>
+IObjectBase* CastToObjectBaseImpl(TUserObj* p, void*);
+template <class TUserObj>
+IObjectBase* CastToObjectBaseImpl(TUserObj* p, IObjectBase*) {
+    return p;
+}
+template <class TUserObj>
+TUserObj* CastToUserObjectImpl(IObjectBase* p, TUserObj*, void*);
+template <class TUserObj>
+TUserObj* CastToUserObjectImpl(IObjectBase* _p, TUserObj*, IObjectBase*) {
+    return dynamic_cast<TUserObj*>(_p);
+}
+template <class TUserObj>
+inline IObjectBase* CastToObjectBase(TUserObj* p) {
+    return CastToObjectBaseImpl(p, p);
+}
+template <class TUserObj>
+inline const IObjectBase* CastToObjectBase(const TUserObj* p) {
+    return p;
+}
+template <class TUserObj>
+inline TUserObj* CastToUserObject(IObjectBase* p, TUserObj* pu) {
+    return CastToUserObjectImpl(p, pu, pu);
+}
+////////////////////////////////////////////////////////////////////////////////////////////////////
+// TObject - base object for reference counting, TUserObj - user object name
+// TRef - struct with AddRef/DecRef/Release methods for refcounting to use
+template <class TUserObj, class TRef>
+class TPtrBase {
+private:
+    TUserObj* ptr;
+
+    void AddRef(TUserObj* _ptr) {
+        TRef p;
+        if (_ptr)
+            p.AddRef(CastToObjectBase(_ptr));
+    }
+    void DecRef(TUserObj* _ptr) {
+        TRef p;
+        if (_ptr)
+            p.DecRef(CastToObjectBase(_ptr));
+    }
+    void Release(TUserObj* _ptr) {
+        TRef p;
+        if (_ptr)
+            p.Release(CastToObjectBase(_ptr));
+    }
+
+protected:
+    void SetObject(TUserObj* _ptr) {
+        TUserObj* pOld = ptr;
+        ptr = _ptr;
+        AddRef(ptr);
+        Release(pOld);
+    }
+
+public:
+    TPtrBase()
+        : ptr(nullptr)
+    {
+    }
+    TPtrBase(TUserObj* _ptr)
+        : ptr(_ptr)
+    {
+        AddRef(ptr);
+    }
+    TPtrBase(const TPtrBase& a)
+        : ptr(a.ptr)
+    {
+        AddRef(ptr);
+    }
+    ~TPtrBase() {
+        Release(ptr);
+    }
+
+    void Set(TUserObj* _ptr) {
+        SetObject(_ptr);
+    }
+    TUserObj* Extract() {
+        TUserObj* pRes = ptr;
+        DecRef(ptr);
+        ptr = nullptr;
+        return pRes;
+    }
+
+    const char* GetClassName() const {
+        return ptr->GetClassName();
+    }
+
+    // assignment operators
+    TPtrBase& operator=(TUserObj* _ptr) {
+        Set(_ptr);
+        return *this;
+    }
+    TPtrBase& operator=(const TPtrBase& a) {
+        Set(a.ptr);
+        return *this;
+    }
+    // access
+    TUserObj* operator->() const {
+        return ptr;
+    }
+    operator TUserObj*() const {
+        return ptr;
+    }
+    TUserObj* Get() const {
+        return ptr;
+    }
+    IObjectBase* GetBarePtr() const {
+        return CastToObjectBase(ptr);
+    }
+    int operator&(IBinSaver& f);
+};
+////////////////////////////////////////////////////////////////////////////////////////////////////
+template <class T>
+inline bool IsValid(T* p) {
+    return p != nullptr && !CastToObjectBase(p)->IsRefInvalid();
+}
+template <class T, class TRef>
+inline bool IsValid(const TPtrBase<T, TRef>& p) {
+    return p.Get() && !p.GetBarePtr()->IsRefInvalid();
+}
+////////////////////////////////////////////////////////////////////////////////////////////////////
+#define BASIC_PTR_DECLARE(TPtrName, TRef)        \
+    template <class T>                           \
+    class TPtrName: public TPtrBase<T, TRef> {   \
+        using CBase = TPtrBase<T, TRef>;         \
+                                                 \
+    public:                                      \
+        using CDestType = T;                     \
+        TPtrName() {                             \
+        }                                        \
+        TPtrName(T* _ptr)                        \
+            : CBase(_ptr)                        \
+        {                                        \
+        }                                        \
+        TPtrName(const TPtrName& a)              \
+            : CBase(a)                           \
+        {                                        \
+        }                                        \
+        TPtrName& operator=(T* _ptr) {           \
+            this->Set(_ptr);                     \
+            return *this;                        \
+        }                                        \
+        TPtrName& operator=(const TPtrName& a) { \
+            this->SetObject(a.Get());            \
+            return *this;                        \
+        }                                        \
+        int operator&(IBinSaver& f) {            \
+            return (*(CBase*)this) & (f);        \
+        }                                        \
+    };
+
+BASIC_PTR_DECLARE(TPtr, IObjectBase::TRef)
+BASIC_PTR_DECLARE(TObj, IObjectBase::TRefO)
+BASIC_PTR_DECLARE(TMObj, IObjectBase::TRefM)
+// misuse guard
+template <class T>
+inline bool IsValid(TObj<T>* p) {
+    return p->YouHaveMadeMistake();
+}
+template <class T>
+inline bool IsValid(TPtr<T>* p) {
+    return p->YouHaveMadeMistake();
+}
+template <class T>
+inline bool IsValid(TMObj<T>* p) {
+    return p->YouHaveMadeMistake();
+}
+////////////////////////////////////////////////////////////////////////////////////////////////////
+// assumes base class is IObjectBase
+template <class T>
+class TDynamicCast {
+    T* ptr;
+
+public:
+    template <class TT>
+    TDynamicCast(TT* _ptr) {
+        ptr = dynamic_cast<T*>(CastToObjectBase(_ptr));
+    }
+    template <class TT>
+    TDynamicCast(const TT* _ptr) {
+        ptr = dynamic_cast<T*>(CastToObjectBase(const_cast<TT*>(_ptr)));
+    }
+    template <class T1, class T2>
+    TDynamicCast(const TPtrBase<T1, T2>& _ptr) {
+        ptr = dynamic_cast<T*>(_ptr.GetBarePtr());
+    }
+    operator T*() const {
+        return ptr;
+    }
+    T* operator->() const {
+        return ptr;
+    }
+    T* Get() const {
+        return ptr;
+    }
+};
+template <class T>
+inline bool IsValid(const TDynamicCast<T>& p) {
+    return IsValid(p.Get());
+}