| /* |
| * Copyright (C) 2006, 2007, 2008 Apple Inc. All rights reserved. |
| * |
| * This library is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Library General Public |
| * License as published by the Free Software Foundation; either |
| * version 2 of the License, or (at your option) any later version. |
| * |
| * This library is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Library General Public License for more details. |
| * |
| * You should have received a copy of the GNU Library General Public License |
| * along with this library; see the file COPYING.LIB. If not, write to |
| * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, |
| * Boston, MA 02110-1301, USA. |
| * |
| */ |
| |
| #ifndef WTF_VectorTraits_h |
| #define WTF_VectorTraits_h |
| |
| #include <wtf/OwnPtr.h> |
| #include <wtf/RefPtr.h> |
| #include <wtf/TypeTraits.h> |
| #include <utility> |
| #include <memory> |
| |
| using std::pair; |
| |
| namespace WTF { |
| |
| class AtomicString; |
| |
| template<bool isPod, typename T> |
| struct VectorTraitsBase; |
| |
| template<typename T> |
| struct VectorTraitsBase<false, T> |
| { |
| static const bool needsDestruction = true; |
| static const bool needsInitialization = true; |
| static const bool canInitializeWithMemset = false; |
| static const bool canMoveWithMemcpy = false; |
| static const bool canCopyWithMemcpy = false; |
| static const bool canFillWithMemset = false; |
| static const bool canCompareWithMemcmp = false; |
| }; |
| |
| template<typename T> |
| struct VectorTraitsBase<true, T> |
| { |
| static const bool needsDestruction = false; |
| static const bool needsInitialization = false; |
| static const bool canInitializeWithMemset = false; |
| static const bool canMoveWithMemcpy = true; |
| static const bool canCopyWithMemcpy = true; |
| static const bool canFillWithMemset = sizeof(T) == sizeof(char); |
| static const bool canCompareWithMemcmp = true; |
| }; |
| |
| template<typename T> |
| struct VectorTraits : VectorTraitsBase<IsPod<T>::value, T> { }; |
| |
| struct SimpleClassVectorTraits : VectorTraitsBase<false, void> |
| { |
| static const bool canInitializeWithMemset = true; |
| static const bool canMoveWithMemcpy = true; |
| static const bool canCompareWithMemcmp = true; |
| }; |
| |
| // we know OwnPtr and RefPtr are simple enough that initializing to 0 and moving with memcpy |
| // (and then not destructing the original) will totally work |
| template<typename P> |
| struct VectorTraits<RefPtr<P> > : SimpleClassVectorTraits { }; |
| |
| template<typename P> |
| struct VectorTraits<OwnPtr<P> > : SimpleClassVectorTraits { }; |
| |
| template<> |
| struct VectorTraits<AtomicString> : SimpleClassVectorTraits { }; |
| |
| template<typename First, typename Second> |
| struct VectorTraits<pair<First, Second> > |
| { |
| typedef VectorTraits<First> FirstTraits; |
| typedef VectorTraits<Second> SecondTraits; |
| |
| static const bool needsDestruction = FirstTraits::needsDestruction || SecondTraits::needsDestruction; |
| static const bool needsInitialization = FirstTraits::needsInitialization || SecondTraits::needsInitialization; |
| static const bool canInitializeWithMemset = FirstTraits::canInitializeWithMemset && SecondTraits::canInitializeWithMemset; |
| static const bool canMoveWithMemcpy = FirstTraits::canMoveWithMemcpy && SecondTraits::canMoveWithMemcpy; |
| static const bool canCopyWithMemcpy = FirstTraits::canCopyWithMemcpy && SecondTraits::canCopyWithMemcpy; |
| static const bool canFillWithMemset = false; |
| static const bool canCompareWithMemcmp = FirstTraits::canCompareWithMemcmp && SecondTraits::canCompareWithMemcmp; |
| }; |
| |
| } // namespace WTF |
| |
| using WTF::VectorTraits; |
| using WTF::SimpleClassVectorTraits; |
| |
| #endif // WTF_VectorTraits_h |