2 * Copyright (C) 2006, 2007, 2008 Apple Inc. All rights reserved.
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Library General Public License for more details.
14 * You should have received a copy of the GNU Library General Public License
15 * along with this library; see the file COPYING.LIB. If not, write to
16 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
17 * Boston, MA 02110-1301, USA.
21 #ifndef WTF_VectorTraits_h
22 #define WTF_VectorTraits_h
24 #include <wtf/OwnPtr.h>
25 #include <wtf/RefPtr.h>
26 #include <wtf/TypeTraits.h>
34 template<bool isPod, typename T>
35 struct VectorTraitsBase;
38 struct VectorTraitsBase<false, T>
40 static const bool needsDestruction = true;
41 static const bool needsInitialization = true;
42 static const bool canInitializeWithMemset = false;
43 static const bool canMoveWithMemcpy = false;
44 static const bool canCopyWithMemcpy = false;
45 static const bool canFillWithMemset = false;
46 static const bool canCompareWithMemcmp = false;
50 struct VectorTraitsBase<true, T>
52 static const bool needsDestruction = false;
53 static const bool needsInitialization = false;
54 static const bool canInitializeWithMemset = false;
55 static const bool canMoveWithMemcpy = true;
56 static const bool canCopyWithMemcpy = true;
57 static const bool canFillWithMemset = sizeof(T) == sizeof(char);
58 static const bool canCompareWithMemcmp = true;
62 struct VectorTraits : VectorTraitsBase<IsPod<T>::value, T> { };
64 struct SimpleClassVectorTraits : VectorTraitsBase<false, void>
66 static const bool canInitializeWithMemset = true;
67 static const bool canMoveWithMemcpy = true;
68 static const bool canCompareWithMemcmp = true;
71 // we know OwnPtr and RefPtr are simple enough that initializing to 0 and moving with memcpy
72 // (and then not destructing the original) will totally work
74 struct VectorTraits<RefPtr<P> > : SimpleClassVectorTraits { };
77 struct VectorTraits<OwnPtr<P> > : SimpleClassVectorTraits { };
79 template<typename First, typename Second>
80 struct VectorTraits<pair<First, Second> >
82 typedef VectorTraits<First> FirstTraits;
83 typedef VectorTraits<Second> SecondTraits;
85 static const bool needsDestruction = FirstTraits::needsDestruction || SecondTraits::needsDestruction;
86 static const bool needsInitialization = FirstTraits::needsInitialization || SecondTraits::needsInitialization;
87 static const bool canInitializeWithMemset = FirstTraits::canInitializeWithMemset && SecondTraits::canInitializeWithMemset;
88 static const bool canMoveWithMemcpy = FirstTraits::canMoveWithMemcpy && SecondTraits::canMoveWithMemcpy;
89 static const bool canCopyWithMemcpy = FirstTraits::canCopyWithMemcpy && SecondTraits::canCopyWithMemcpy;
90 static const bool canFillWithMemset = false;
91 static const bool canCompareWithMemcmp = FirstTraits::canCompareWithMemcmp && SecondTraits::canCompareWithMemcmp;
96 using WTF::VectorTraits;
97 using WTF::SimpleClassVectorTraits;
99 #endif // WTF_VectorTraits_h