/* * Copyright (C) 2008-2019 Apple 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 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. */ #pragma once #include <wtf/text/AtomString.h> #include <wtf/HashTraits.h> namespace WTF { struct AtomStringHash { static unsigned hash(const AtomString& key) { return key.impl()->existingHash(); } static bool equal(const AtomString& a, const AtomString& b) { return a == b; } static constexpr bool safeToCompareToEmptyOrDeleted = false; }; template<> struct HashTraits<WTF::AtomString> : SimpleClassHashTraits<WTF::AtomString> { static constexpr bool hasIsEmptyValueFunction = true; static bool isEmptyValue(const AtomString& value) { return value.isNull(); } static void customDeleteBucket(AtomString& value) { // See unique_ptr's customDeleteBucket() for an explanation. ASSERT(!isDeletedValue(value)); AtomString valueToBeDestroyed = WTFMove(value); constructDeletedValue(value); } }; template<> struct DefaultHash<AtomString> : AtomStringHash { }; } using WTF::AtomStringHash;