atomicstringhash.h

来自「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Web」· C头文件 代码 · 共 65 行

/*
 * Copyright (C) 2008 Apple Inc. All rights reserved.
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 *
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 *     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
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#ifndef AtomicStringHash_h
#define AtomicStringHash_h

#include "AtomicString.h"
#include <wtf/HashTraits.h>

namespace WebCore {

    struct AtomicStringHash {
        static unsigned hash(const AtomicString& key)
        {
            return key.impl()->existingHash();
        }

        static bool equal(const AtomicString& a, const AtomicString& b)
        {
            return a == b;
        }

        static const bool safeToCompareToEmptyOrDeleted = false;
    };

}

namespace WTF {

    // WebCore::AtomicStringHash is the default hash for AtomicString
    template<> struct HashTraits<WebCore::AtomicString> : GenericHashTraits<WebCore::AtomicString> {
        static const bool emptyValueIsZero = true;
        static void constructDeletedValue(WebCore::AtomicString& slot) { new (&slot) WebCore::AtomicString(HashTableDeletedValue); }
        static bool isDeletedValue(const WebCore::AtomicString& slot) { return slot.isHashTableDeletedValue(); }
    };

}

#endif