deque.h

linux下开源浏览器WebKit的源码,市面上的很多商用浏览器都是移植自WebKit

/*
 * Copyright (C) 2007, 2008 Apple Inc. All rights reserved.
 * Copyright (C) 2009 Google Inc. 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 WTF_Deque_h
#define WTF_Deque_h

// FIXME: Could move what Vector and Deque share into a separate file.
// Deque doesn't actually use Vector.

#include "Vector.h"

namespace WTF {

    template<typename T> class DequeIteratorBase;
    template<typename T> class DequeIterator;
    template<typename T> class DequeConstIterator;
    template<typename T> class DequeReverseIterator;
    template<typename T> class DequeConstReverseIterator;

    template<typename T>
    class Deque {
    public:
        typedef DequeIterator<T> iterator;
        typedef DequeConstIterator<T> const_iterator;
        typedef DequeReverseIterator<T> reverse_iterator;
        typedef DequeConstReverseIterator<T> const_reverse_iterator;

        Deque();
        Deque(const Deque<T>&);
        Deque& operator=(const Deque<T>&);
        ~Deque();

        void swap(Deque<T>&);

        size_t size() const { return m_start <= m_end ? m_end - m_start : m_end + m_buffer.capacity() - m_start; }
        bool isEmpty() const { return m_start == m_end; }

        iterator begin() { return iterator(this, m_start); }
        iterator end() { return iterator(this, m_end); }
        const_iterator begin() const { return const_iterator(this, m_start); }
        const_iterator end() const { return const_iterator(this, m_end); }
        reverse_iterator rbegin() { return reverse_iterator(this, m_end); }
        reverse_iterator rend() { return reverse_iterator(this, m_start); }
        const_reverse_iterator rbegin() const { return const_reverse_iterator(this, m_end); }
        const_reverse_iterator rend() const { return const_reverse_iterator(this, m_start); }

        T& first() { ASSERT(m_start != m_end); return m_buffer.buffer()[m_start]; }
        const T& first() const { ASSERT(m_start != m_end); return m_buffer.buffer()[m_start]; }

        template<typename U> void append(const U&);
        template<typename U> void prepend(const U&);
        void removeFirst();
        void remove(iterator&);
        void remove(const_iterator&);

        void clear();

        template<typename Predicate>
        iterator findIf(Predicate&);

    private:
        friend class DequeIteratorBase<T>;

        typedef VectorBuffer<T, 0> Buffer;
        typedef VectorTypeOperations<T> TypeOperations;
        typedef DequeIteratorBase<T> IteratorBase;

        void remove(size_t position);
        void invalidateIterators();
        void destroyAll();
        void checkValidity() const;
        void checkIndexValidity(size_t) const;
        void expandCapacityIfNeeded();
        void expandCapacity();

        size_t m_start;
        size_t m_end;
        Buffer m_buffer;
#ifndef NDEBUG
        mutable IteratorBase* m_iterators;
#endif
    };

    template<typename T>
    class DequeIteratorBase {
    private:
        typedef DequeIteratorBase<T> Base;

    protected:
        DequeIteratorBase();
        DequeIteratorBase(const Deque<T>*, size_t);
        DequeIteratorBase(const Base&);
        Base& operator=(const Base&);
        ~DequeIteratorBase();

        void assign(const Base& other) { *this = other; }

        void increment();
        void decrement();

        T* before() const;
        T* after() const;

        bool isEqual(const Base&) const;

    private:
        void addToIteratorsList();
        void removeFromIteratorsList();
        void checkValidity() const;
        void checkValidity(const Base&) const;

        Deque<T>* m_deque;
        size_t m_index;

        friend class Deque<T>;

#ifndef NDEBUG
        mutable DequeIteratorBase* m_next;
        mutable DequeIteratorBase* m_previous;
#endif
    };

    template<typename T>
    class DequeIterator : public DequeIteratorBase<T> {
    private:
        typedef DequeIteratorBase<T> Base;
        typedef DequeIterator<T> Iterator;

    public:
        DequeIterator(Deque<T>* deque, size_t index) : Base(deque, index) { }

        DequeIterator(const Iterator& other) : Base(other) { }
        DequeIterator& operator=(const Iterator& other) { Base::assign(other); return *this; }

        T& operator*() const { return *Base::after(); }
        T* operator->() const { return Base::after(); }

        bool operator==(const Iterator& other) const { return Base::isEqual(other); }
        bool operator!=(const Iterator& other) const { return !Base::isEqual(other); }

        Iterator& operator++() { Base::increment(); return *this; }
        // postfix ++ intentionally omitted
        Iterator& operator--() { Base::decrement(); return *this; }
        // postfix -- intentionally omitted
    };

    template<typename T>
    class DequeConstIterator : public DequeIteratorBase<T> {
    private:
        typedef DequeIteratorBase<T> Base;
        typedef DequeConstIterator<T> Iterator;
        typedef DequeIterator<T> NonConstIterator;

    public:
        DequeConstIterator(const Deque<T>* deque, size_t index) : Base(deque, index) { }

        DequeConstIterator(const Iterator& other) : Base(other) { }
        DequeConstIterator(const NonConstIterator& other) : Base(other) { }
        DequeConstIterator& operator=(const Iterator& other) { Base::assign(other); return *this; }
        DequeConstIterator& operator=(const NonConstIterator& other) { Base::assign(other); return *this; }

        const T& operator*() const { return *Base::after(); }
        const T* operator->() const { return Base::after(); }

        bool operator==(const Iterator& other) const { return Base::isEqual(other); }
        bool operator!=(const Iterator& other) const { return !Base::isEqual(other); }

        Iterator& operator++() { Base::increment(); return *this; }
        // postfix ++ intentionally omitted
        Iterator& operator--() { Base::decrement(); return *this; }
        // postfix -- intentionally omitted
    };

    template<typename T>
    class DequeReverseIterator : public DequeIteratorBase<T> {
    private:
        typedef DequeIteratorBase<T> Base;
        typedef DequeReverseIterator<T> Iterator;

    public:
        DequeReverseIterator(const Deque<T>* deque, size_t index) : Base(deque, index) { }

        DequeReverseIterator(const Iterator& other) : Base(other) { }
        DequeReverseIterator& operator=(const Iterator& other) { Base::assign(other); return *this; }

        T& operator*() const { return *Base::before(); }
        T* operator->() const { return Base::before(); }

        bool operator==(const Iterator& other) const { return Base::isEqual(other); }
        bool operator!=(const Iterator& other) const { return !Base::isEqual(other); }

        Iterator& operator++() { Base::decrement(); return *this; }
        // postfix ++ intentionally omitted
        Iterator& operator--() { Base::increment(); return *this; }
        // postfix -- intentionally omitted
    };

    template<typename T>
    class DequeConstReverseIterator : public DequeIteratorBase<T> {
    private:
        typedef DequeIteratorBase<T> Base;
        typedef DequeConstReverseIterator<T> Iterator;
        typedef DequeReverseIterator<T> NonConstIterator;

    public:
        DequeConstReverseIterator(const Deque<T>* deque, size_t index) : Base(deque, index) { }

        DequeConstReverseIterator(const Iterator& other) : Base(other) { }
        DequeConstReverseIterator(const NonConstIterator& other) : Base(other) { }
        DequeConstReverseIterator& operator=(const Iterator& other) { Base::assign(other); return *this; }
        DequeConstReverseIterator& operator=(const NonConstIterator& other) { Base::assign(other); return *this; }

        const T& operator*() const { return *Base::before(); }
        const T* operator->() const { return Base::before(); }

        bool operator==(const Iterator& other) const { return Base::isEqual(other); }
        bool operator!=(const Iterator& other) const { return !Base::isEqual(other); }

        Iterator& operator++() { Base::decrement(); return *this; }
        // postfix ++ intentionally omitted
        Iterator& operator--() { Base::increment(); return *this; }
        // postfix -- intentionally omitted
    };

#ifdef NDEBUG
    template<typename T> inline void Deque<T>::checkValidity() const { }
    template<typename T> inline void Deque<T>::checkIndexValidity(size_t) const { }
    template<typename T> inline void Deque<T>::invalidateIterators() { }
#else
    template<typename T>
    void Deque<T>::checkValidity() const
    {
        if (!m_buffer.capacity()) {
            ASSERT(!m_start);
            ASSERT(!m_end);
        } else {
            ASSERT(m_start < m_buffer.capacity());
            ASSERT(m_end < m_buffer.capacity());
        }
    }

    template<typename T>
    void Deque<T>::checkIndexValidity(size_t index) const
    {
        ASSERT(index <= m_buffer.capacity());
        if (m_start <= m_end) {
            ASSERT(index >= m_start);
            ASSERT(index <= m_end);
        } else {
            ASSERT(index >= m_start || index <= m_end);
        }
    }

    template<typename T>
    void Deque<T>::invalidateIterators()
    {
        IteratorBase* next;
        for (IteratorBase* p = m_iterators; p; p = next) {
            next = p->m_next;
            p->m_deque = 0;
            p->m_next = 0;
            p->m_previous = 0;
        }
        m_iterators = 0;
    }
#endif

    template<typename T>
    inline Deque<T>::Deque()
        : m_start(0)
        , m_end(0)
#ifndef NDEBUG
        , m_iterators(0)
#endif
    {
        checkValidity();
    }

    template<typename T>
    inline Deque<T>::Deque(const Deque<T>& other)
        : m_start(other.m_start)
        , m_end(other.m_end)
        , m_buffer(other.m_buffer.capacity())
#ifndef NDEBUG
        , m_iterators(0)
#endif
    {
        const T* otherBuffer = other.m_buffer.buffer();
        if (m_start <= m_end)
            TypeOperations::uninitializedCopy(otherBuffer + m_start, otherBuffer + m_end, m_buffer.buffer() + m_start);
        else {
            TypeOperations::uninitializedCopy(otherBuffer, otherBuffer + m_end, m_buffer.buffer());
            TypeOperations::uninitializedCopy(otherBuffer + m_start, otherBuffer + m_buffer.capacity(), m_buffer.buffer() + m_start);
        }
    }

    template<typename T>
    void deleteAllValues(const Deque<T>& collection)
    {
        typedef typename Deque<T>::const_iterator iterator;
        iterator end = collection.end();
        for (iterator it = collection.begin(); it != end; ++it)
            delete *it;
    }

    template<typename T>
    inline Deque<T>& Deque<T>::operator=(const Deque<T>& other)
    {
        Deque<T> copy(other);