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 <string.h> 30#include <wtf/Forward.h> 31#include <wtf/HashTraits.h> 32 33namespace IPC { 34 35class ArgumentEncoder; 36class ArgumentDecoder; 37 38class StringReference { 39public: 40 StringReference() 41 : m_data(0) 42 , m_size(0) 43 { 44 } 45 46 StringReference(const char* data, size_t size) 47 : m_data(data) 48 , m_size(size) 49 { 50 } 51 52 template<size_t length> 53 StringReference(const char (&string)[length]) 54 : m_data(string) 55 , m_size(length - 1) 56 { 57 } 58 59 bool isEmpty() const { return !m_size; } 60 61 size_t size() const { return m_size; } 62 const char* data() const { return m_data; } 63 64 CString toString() const; 65 66 friend bool operator==(const StringReference& a, const StringReference& b) 67 { 68 return a.m_size == b.m_size && !memcmp(a.m_data, b.m_data, a.m_size); 69 } 70 71 void encode(ArgumentEncoder&) const; 72 static bool decode(ArgumentDecoder&, StringReference&); 73 74 struct Hash { 75 static unsigned hash(const StringReference& a); 76 static bool equal(const StringReference& a, const StringReference& b) { return a == b; } 77 static const bool safeToCompareToEmptyOrDeleted = true; 78 }; 79 80private: 81 const char* m_data; 82 size_t m_size; 83}; 84 85} // namespace IPC 86 87namespace WTF { 88template<typename T> struct DefaultHash; 89 90template<> struct DefaultHash<IPC::StringReference> { 91 typedef IPC::StringReference::Hash Hash; 92}; 93 94template<> struct HashTraits<IPC::StringReference> : GenericHashTraits<IPC::StringReference> { 95 static const bool emptyValueIsZero = 0; 96 static void constructDeletedValue(IPC::StringReference& stringReference) { stringReference = IPC::StringReference(0, std::numeric_limits<size_t>::max()); } 97 static bool isDeletedValue(const IPC::StringReference& stringReference) { return stringReference.size() == std::numeric_limits<size_t>::max(); } 98}; 99 100} // namespace WTF 101 102#endif // StringReference_h 103