/*

 * Copyright (C) 2008, 2009 Paul Pedriana <ppedriana@ea.com>. All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 *

 * 1.  Redistributions of source code must retain the above copyright

 *     notice, this list of conditions and the following disclaimer.

 * 2.  Redistributions in binary form must reproduce the above copyright

 *     notice, this list of conditions and the following disclaimer in the

 *     documentation and/or other materials provided with the distribution.

 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of

 *     its contributors may be used to endorse or promote products derived

 *     from this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY

 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE

 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY

 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES

 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;

 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND

 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF

 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */

#ifndef FastAllocBase_h

#define FastAllocBase_h

// Provides customizable overrides of fastMalloc/fastFree and operator new/delete

//

// Provided functionality:

//    namespace WTF {

//        class FastAllocBase;

//

//        T*    fastNew<T>();

//        T*    fastNew<T>(arg);

//        T*    fastNew<T>(arg, arg);

//        T*    fastNewArray<T>(count);

//        void  fastDelete(T* p);

//        void  fastDeleteArray(T* p);

//        void  fastNonNullDelete(T* p);

//        void  fastNonNullDeleteArray(T* p);

//    }

//

// FastDelete assumes that the underlying

//

// Example usage:

//    class Widget : public FastAllocBase { ... };

//

//    char* charPtr = fastNew<char>();

//    fastDelete(charPtr);

//

//    char* charArrayPtr = fastNewArray<char>(37);

//    fastDeleteArray(charArrayPtr);

//

//    void** voidPtrPtr = fastNew<void*>();

//    fastDelete(voidPtrPtr);

//

//    void** voidPtrArrayPtr = fastNewArray<void*>(37);

//    fastDeleteArray(voidPtrArrayPtr);

//

//    POD* podPtr = fastNew<POD>();

//    fastDelete(podPtr);

//

//    POD* podArrayPtr = fastNewArray<POD>(37);

//    fastDeleteArray(podArrayPtr);

//

//    Object* objectPtr = fastNew<Object>();

//    fastDelete(objectPtr);

//

//    Object* objectArrayPtr = fastNewArray<Object>(37);

//    fastDeleteArray(objectArrayPtr);

//

#include <new>

#include <stdint.h>

#include <stdlib.h>

#include <string.h>

#include "Assertions.h"

#include "FastMalloc.h"

#include "TypeTraits.h"

namespace WTF {

    class FastAllocBase {

    public:

        // Placement operator new.

        void* operator new(size_t, void* p) { return p; }

        void* operator new[](size_t, void* p) { return p; }

        void* operator new(size_t size)

        {

            void* p = fastMalloc(size);

            fastMallocMatchValidateMalloc(p, Internal::AllocTypeClassNew);

            return p;

        }

        void operator delete(void* p)

        {

            fastMallocMatchValidateFree(p, Internal::AllocTypeClassNew);

            fastFree(p);

        }

        void* operator new[](size_t size)

        {

            void* p = fastMalloc(size);

            fastMallocMatchValidateMalloc(p, Internal::AllocTypeClassNewArray);

            return p;

        }

        void operator delete[](void* p)

        {

            fastMallocMatchValidateFree(p, Internal::AllocTypeClassNewArray);

            fastFree(p);

        }

    };

    // fastNew / fastDelete

    template <typename T>

    inline T* fastNew()

    {

        void* p = fastMalloc(sizeof(T));

        if (!p)

            return 0;

        fastMallocMatchValidateMalloc(p, Internal::AllocTypeFastNew);

        return ::new(p) T;

    }

    template <typename T, typename Arg1>

    inline T* fastNew(Arg1 arg1)

    {

        void* p = fastMalloc(sizeof(T));

        if (!p)

            return 0;

        fastMallocMatchValidateMalloc(p, Internal::AllocTypeFastNew);

        return ::new(p) T(arg1);

    }

    template <typename T, typename Arg1, typename Arg2>

    inline T* fastNew(Arg1 arg1, Arg2 arg2)

    {

        void* p = fastMalloc(sizeof(T));

        if (!p)

            return 0;

        fastMallocMatchValidateMalloc(p, Internal::AllocTypeFastNew);

        return ::new(p) T(arg1, arg2);

    }

    template <typename T, typename Arg1, typename Arg2, typename Arg3>

    inline T* fastNew(Arg1 arg1, Arg2 arg2, Arg3 arg3)

    {

        void* p = fastMalloc(sizeof(T));

        if (!p)

            return 0;

        fastMallocMatchValidateMalloc(p, Internal::AllocTypeFastNew);

        return ::new(p) T(arg1, arg2, arg3);

    }

    template <typename T, typename Arg1, typename Arg2, typename Arg3, typename Arg4>

    inline T* fastNew(Arg1 arg1, Arg2 arg2, Arg3 arg3, Arg4 arg4)

    {

        void* p = fastMalloc(sizeof(T));

        if (!p)

            return 0;

        fastMallocMatchValidateMalloc(p, Internal::AllocTypeFastNew);

        return ::new(p) T(arg1, arg2, arg3, arg4);

    }

    template <typename T, typename Arg1, typename Arg2, typename Arg3, typename Arg4, typename Arg5>

    inline T* fastNew(Arg1 arg1, Arg2 arg2, Arg3 arg3, Arg4 arg4, Arg5 arg5)

    {

        void* p = fastMalloc(sizeof(T));

        if (!p)

            return 0;

        fastMallocMatchValidateMalloc(p, Internal::AllocTypeFastNew);

        return ::new(p) T(arg1, arg2, arg3, arg4, arg5);

    }

    namespace Internal {

        // We define a union of pointer to an integer and pointer to T.

        // When non-POD arrays are allocated we add a few leading bytes to tell what

        // the size of the array is. We return to the user the pointer to T.

        // The way to think of it is as if we allocate a struct like so:

        //    struct Array {

        //        AllocAlignmentInteger m_size;

        //        T m_T[array count];

        //    };

        template <typename T>

        union ArraySize {

            AllocAlignmentInteger* size;

            T* t;

        };

        // This is a support template for fastNewArray.

        // This handles the case wherein T has a trivial ctor and a trivial dtor.

        template <typename T, bool trivialCtor, bool trivialDtor>

        struct NewArrayImpl {

            static T* fastNewArray(size_t count)

            {

                T* p = static_cast<T*>(fastMalloc(sizeof(T) * count));

                fastMallocMatchValidateMalloc(p, Internal::AllocTypeFastNewArray);

                return p;

            }

        };

        // This is a support template for fastNewArray.

        // This handles the case wherein T has a non-trivial ctor and a trivial dtor.

        template <typename T>

        struct NewArrayImpl<T, false, true> {

            static T* fastNewArray(size_t count)

            {

                T* p = static_cast<T*>(fastMalloc(sizeof(T) * count));

                if (!p)

                    return 0;

                fastMallocMatchValidateMalloc(p, Internal::AllocTypeFastNewArray);

                for (T* pObject = p, *pObjectEnd = pObject + count; pObject != pObjectEnd; ++pObject)

                    ::new(pObject) T;

                return p;

            }

        };

        // This is a support template for fastNewArray.

        // This handles the case wherein T has a trivial ctor and a non-trivial dtor.

        template <typename T>

        struct NewArrayImpl<T, true, false> {

            static T* fastNewArray(size_t count)

            {

                void* p = fastMalloc(sizeof(AllocAlignmentInteger) + (sizeof(T) * count));

                ArraySize<T> a = { static_cast<AllocAlignmentInteger*>(p) };

                if (!p)

                    return 0;

                fastMallocMatchValidateMalloc(p, Internal::AllocTypeFastNewArray);

                *a.size++ = count;

                // No need to construct the objects in this case.

                return a.t;

            }

        };

        // This is a support template for fastNewArray.

        // This handles the case wherein T has a non-trivial ctor and a non-trivial dtor.

        template <typename T>

        struct NewArrayImpl<T, false, false> {

            static T* fastNewArray(size_t count)

            {

                void* p = fastMalloc(sizeof(AllocAlignmentInteger) + (sizeof(T) * count));

                ArraySize<T> a = { static_cast<AllocAlignmentInteger*>(p) };

                if (!p)

                    return 0;

                fastMallocMatchValidateMalloc(p, Internal::AllocTypeFastNewArray);

                *a.size++ = count;

                for (T* pT = a.t, *pTEnd = pT + count; pT != pTEnd; ++pT)

                    ::new(pT) T;

                return a.t;

            }

        };

    } // namespace Internal

    template <typename T>

    inline T* fastNewArray(size_t count)

    {

        return Internal::NewArrayImpl<T, WTF::HasTrivialConstructor<T>::value, WTF::HasTrivialDestructor<T>::value>::fastNewArray(count);

    }

    template <typename T>

    inline void fastDelete(T* p)

    {

        if (!p)

            return;

        fastMallocMatchValidateFree(p, Internal::AllocTypeFastNew);

        p->~T();

        fastFree(p);

    }

    template <typename T>

    inline void fastDeleteSkippingDestructor(T* p)

    {

        if (!p)

            return;

        fastMallocMatchValidateFree(p, Internal::AllocTypeFastNew);

        fastFree(p);

    }

    namespace Internal {

        // This is a support template for fastDeleteArray.

        // This handles the case wherein T has a trivial dtor.

        template <typename T, bool trivialDtor>

        struct DeleteArrayImpl {

            static void fastDeleteArray(void* p)

            {

                // No need to destruct the objects in this case.

                // We expect that fastFree checks for null.

                fastMallocMatchValidateFree(p, Internal::AllocTypeFastNewArray);

                fastFree(p);

            }

        };

        // This is a support template for fastDeleteArray.

        // This handles the case wherein T has a non-trivial dtor.

        template <typename T>

        struct DeleteArrayImpl<T, false> {

            static void fastDeleteArray(T* p)

            {

                if (!p)

                    return;

                ArraySize<T> a;

                a.t = p;

                a.size--; // Decrement size pointer

                T* pEnd = p + *a.size;

                while (pEnd-- != p)

                    pEnd->~T();

                fastMallocMatchValidateFree(a.size, Internal::AllocTypeFastNewArray);

                fastFree(a.size);

            }

        };

    } // namespace Internal

    template <typename T>

    void fastDeleteArray(T* p)

    {

        Internal::DeleteArrayImpl<T, WTF::HasTrivialDestructor<T>::value>::fastDeleteArray(p);

    }

    template <typename T>

    inline void fastNonNullDelete(T* p)

    {

        fastMallocMatchValidateFree(p, Internal::AllocTypeFastNew);

        p->~T();

        fastFree(p);

    }

    namespace Internal {

        // This is a support template for fastDeleteArray.

        // This handles the case wherein T has a trivial dtor.

        template <typename T, bool trivialDtor>

        struct NonNullDeleteArrayImpl {

            static void fastNonNullDeleteArray(void* p)

            {

                fastMallocMatchValidateFree(p, Internal::AllocTypeFastNewArray);

                // No need to destruct the objects in this case.

                fastFree(p);

            }

        };

        // This is a support template for fastDeleteArray.

        // This handles the case wherein T has a non-trivial dtor.

        template <typename T>

        struct NonNullDeleteArrayImpl<T, false> {

            static void fastNonNullDeleteArray(T* p)

            {

                ArraySize<T> a;

                a.t = p;

                a.size--;

                T* pEnd = p + *a.size;

                while (pEnd-- != p)

                    pEnd->~T();

                fastMallocMatchValidateFree(a.size, Internal::AllocTypeFastNewArray);

                fastFree(a.size);

            }

        };

    } // namespace Internal

    template <typename T>

    void fastNonNullDeleteArray(T* p)

    {

        Internal::NonNullDeleteArrayImpl<T, WTF::HasTrivialDestructor<T>::value>::fastNonNullDeleteArray(p);

    }

} // namespace WTF

using WTF::FastAllocBase;

using WTF::fastDeleteSkippingDestructor;

#endif // FastAllocBase_h