1/* 2 * Copyright (C) 2012 Apple Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' 14 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 15 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS 17 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 18 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 19 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 20 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 21 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 22 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 23 * THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26#ifndef StringReference_h 27#define StringReference_h 28 29#include <wtf/Forward.h> 30#include <wtf/HashTraits.h> 31 32namespace CoreIPC { 33 34class ArgumentEncoder; 35class ArgumentDecoder; 36 37class StringReference { 38public: 39 StringReference() 40 : m_data(0) 41 , m_size(0) 42 { 43 } 44 45 StringReference(const char* data, size_t size) 46 : m_data(data) 47 , m_size(size) 48 { 49 } 50 51 template<size_t length> 52 StringReference(const char (&string)[length]) 53 : m_data(string) 54 , m_size(length - 1) 55 { 56 } 57 58 bool isEmpty() const { return !m_size; } 59 60 size_t size() const { return m_size; } 61 const char* data() const { return m_data; } 62 63 CString toString() const; 64 65 friend bool operator==(const StringReference& a, const StringReference& b) 66 { 67 return a.m_size == b.m_size && !memcmp(a.m_data, b.m_data, a.m_size); 68 } 69 70 void encode(ArgumentEncoder&) const; 71 static bool decode(ArgumentDecoder&, StringReference&); 72 73 struct Hash { 74 static unsigned hash(const StringReference& a); 75 static bool equal(const StringReference& a, const StringReference& b) { return a == b; } 76 static const bool safeToCompareToEmptyOrDeleted = true; 77 }; 78 79private: 80 const char* m_data; 81 size_t m_size; 82}; 83 84} // namespace CoreIPC 85 86namespace WTF { 87template<typename T> struct DefaultHash; 88 89template<> struct DefaultHash<CoreIPC::StringReference> { 90 typedef CoreIPC::StringReference::Hash Hash; 91}; 92 93template<> struct HashTraits<CoreIPC::StringReference> : GenericHashTraits<CoreIPC::StringReference> { 94 static const bool emptyValueIsZero = 0; 95 static void constructDeletedValue(CoreIPC::StringReference& stringReference) { stringReference = CoreIPC::StringReference(0, std::numeric_limits<size_t>::max()); } 96 static bool isDeletedValue(const CoreIPC::StringReference& stringReference) { return stringReference.size() == std::numeric_limits<size_t>::max(); } 97}; 98 99} // namespace WTF 100 101#endif // StringReference_h 102