1 // Copyright 2014 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef MOJO_PUBLIC_CPP_BINDINGS_STRING_H_ 6 #define MOJO_PUBLIC_CPP_BINDINGS_STRING_H_ 7 8 #include <assert.h> 9 10 #include <string> 11 12 #include "mojo/public/cpp/bindings/lib/array_internal.h" 13 #include "mojo/public/cpp/bindings/type_converter.h" 14 #include "mojo/public/cpp/system/macros.h" 15 16 namespace mojo { 17 18 class String { 19 public: 20 typedef internal::String_Data Data_; 21 String()22 String() : is_null_(true) {} String(const std::string & str)23 String(const std::string& str) : value_(str), is_null_(false) {} String(const char * chars)24 String(const char* chars) : is_null_(!chars) { 25 if (chars) 26 value_ = chars; 27 } String(const char * chars,size_t num_chars)28 String(const char* chars, size_t num_chars) 29 : value_(chars, num_chars), 30 is_null_(false) { 31 } 32 template <size_t N> String(const char chars[N])33 String(const char chars[N]) : value_(chars, N-1), is_null_(false) {} 34 35 template <typename U> From(const U & other)36 static String From(const U& other) { 37 return TypeConverter<String, U>::ConvertFrom(other); 38 } 39 40 template <typename U> To()41 U To() const { 42 return TypeConverter<String, U>::ConvertTo(*this); 43 } 44 45 String& operator=(const std::string& str) { 46 value_ = str; 47 is_null_ = false; 48 return *this; 49 } 50 String& operator=(const char* chars) { 51 is_null_ = !chars; 52 if (chars) { 53 value_ = chars; 54 } else { 55 value_.clear(); 56 } 57 return *this; 58 } 59 reset()60 void reset() { 61 value_.clear(); 62 is_null_ = true; 63 } 64 is_null()65 bool is_null() const { return is_null_; } 66 size()67 size_t size() const { return value_.size(); } 68 data()69 const char* data() const { return value_.data(); } 70 at(size_t offset)71 const char& at(size_t offset) const { return value_.at(offset); } 72 const char& operator[](size_t offset) const { return value_[offset]; } 73 get()74 const std::string& get() const { return value_; } 75 operator const std::string&() const { return value_; } 76 Swap(String * other)77 void Swap(String* other) { 78 std::swap(is_null_, other->is_null_); 79 value_.swap(other->value_); 80 } 81 Swap(std::string * other)82 void Swap(std::string* other) { 83 is_null_ = false; 84 value_.swap(*other); 85 } 86 87 private: 88 typedef std::string String::*Testable; 89 90 public: Testable()91 operator Testable() const { return is_null_ ? 0 : &String::value_; } 92 93 private: 94 std::string value_; 95 bool is_null_; 96 }; 97 98 inline bool operator==(const String& a, const String& b) { 99 return a.is_null() == b.is_null() && a.get() == b.get(); 100 } 101 inline bool operator==(const char* a, const String& b) { 102 return !b.is_null() && a == b.get(); 103 } 104 inline bool operator==(const String& a, const char* b) { 105 return !a.is_null() && a.get() == b; 106 } 107 inline bool operator!=(const String& a, const String& b) { return !(a == b); } 108 inline bool operator!=(const char* a, const String& b) { return !(a == b); } 109 inline bool operator!=(const String& a, const char* b) { return !(a == b); } 110 111 // TODO(darin): Add similar variants of operator<,<=,>,>= 112 113 template <> 114 class TypeConverter<String, std::string> { 115 public: ConvertFrom(const std::string & input)116 static String ConvertFrom(const std::string& input) { 117 return String(input); 118 } ConvertTo(const String & input)119 static std::string ConvertTo(const String& input) { 120 return input; 121 } 122 }; 123 124 template <size_t N> 125 class TypeConverter<String, char[N]> { 126 public: ConvertFrom(const char input[N])127 static String ConvertFrom(const char input[N]) { 128 assert(input); 129 return String(input, N-1); 130 } 131 }; 132 133 // Appease MSVC. 134 template <size_t N> 135 class TypeConverter<String, const char[N]> { 136 public: ConvertFrom(const char input[N])137 static String ConvertFrom(const char input[N]) { 138 assert(input); 139 return String(input, N-1); 140 } 141 }; 142 143 template <> 144 class TypeConverter<String, const char*> { 145 public: 146 // |input| may be null, in which case a null String will be returned. ConvertFrom(const char * input)147 static String ConvertFrom(const char* input) { 148 return String(input); 149 } 150 }; 151 152 } // namespace mojo 153 154 #endif // MOJO_PUBLIC_CPP_BINDINGS_STRING_H_ 155