1 // Copyright 2015 Google Inc. All rights reserved 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 // Copyright (c) 2011 The Chromium Authors. All rights reserved. 16 // Use of this source code is governed by a BSD-style license that can be 17 // found in the LICENSE file. 18 // Copied from strings/stringpiece.h with modifications 19 // 20 // A string-like object that points to a sized piece of memory. 21 // 22 // Functions or methods may use const StringPiece& parameters to accept either 23 // a "const char*" or a "string" value that will be implicitly converted to 24 // a StringPiece. The implicit conversion means that it is often appropriate 25 // to include this .h file in other files rather than forward-declaring 26 // StringPiece as would be appropriate for most other Google classes. 27 // 28 // Systematic usage of StringPiece is encouraged as it will reduce unnecessary 29 // conversions from "const char*" to "string" and back again. 30 // 31 32 #ifndef BASE_STRING_PIECE_H_ 33 #define BASE_STRING_PIECE_H_ 34 #pragma once 35 36 #include <stddef.h> 37 #include <string.h> 38 39 #include <string> 40 41 //#include "base/base_api.h" 42 //#include "base/basictypes.h" 43 44 class StringPiece { 45 public: 46 // standard STL container boilerplate 47 typedef size_t size_type; 48 typedef char value_type; 49 typedef const char* pointer; 50 typedef const char& reference; 51 typedef const char& const_reference; 52 typedef ptrdiff_t difference_type; 53 typedef const char* const_iterator; 54 typedef const char* iterator; 55 typedef std::reverse_iterator<const_iterator> const_reverse_iterator; 56 typedef std::reverse_iterator<iterator> reverse_iterator; 57 58 static const size_type npos; 59 60 public: 61 // We provide non-explicit singleton constructors so users can pass 62 // in a "const char*" or a "string" wherever a "StringPiece" is 63 // expected. 64 StringPiece() : ptr_(NULL), length_(0) { } 65 StringPiece(const char* str) 66 : ptr_(str), length_((str == NULL) ? 0 : strlen(str)) { } 67 StringPiece(const std::string& str) 68 : ptr_(str.data()), length_(str.size()) { } 69 StringPiece(const std::string&& str) 70 : ptr_(str.data()), length_(str.size()) { } 71 StringPiece(const char* offset, size_type len) 72 : ptr_(offset), length_(len) { } 73 74 // data() may return a pointer to a buffer with embedded NULs, and the 75 // returned buffer may or may not be null terminated. Therefore it is 76 // typically a mistake to pass data() to a routine that expects a NUL 77 // terminated string. 78 const char* data() const { return ptr_; } 79 size_type size() const { return length_; } 80 size_type length() const { return length_; } 81 bool empty() const { return length_ == 0; } 82 83 void clear() { 84 ptr_ = NULL; 85 length_ = 0; 86 } 87 void set(const char* data, size_type len) { 88 ptr_ = data; 89 length_ = len; 90 } 91 void set(const char* str) { 92 ptr_ = str; 93 length_ = str ? strlen(str) : 0; 94 } 95 void set(const void* data, size_type len) { 96 ptr_ = reinterpret_cast<const char*>(data); 97 length_ = len; 98 } 99 100 char operator[](size_type i) const { return ptr_[i]; } 101 102 void remove_prefix(size_type n) { 103 ptr_ += n; 104 length_ -= n; 105 } 106 107 void remove_suffix(size_type n) { 108 length_ -= n; 109 } 110 111 int compare(const StringPiece& x) const { 112 int r = wordmemcmp( 113 ptr_, x.ptr_, (length_ < x.length_ ? length_ : x.length_)); 114 if (r == 0) { 115 if (length_ < x.length_) r = -1; 116 else if (length_ > x.length_) r = +1; 117 } 118 return r; 119 } 120 121 std::string as_string() const { 122 // std::string doesn't like to take a NULL pointer even with a 0 size. 123 return std::string(!empty() ? data() : "", size()); 124 } 125 126 void CopyToString(std::string* target) const; 127 void AppendToString(std::string* target) const; 128 129 // Does "this" start with "x" 130 bool starts_with(const StringPiece& x) const { 131 return ((length_ >= x.length_) && 132 (wordmemcmp(ptr_, x.ptr_, x.length_) == 0)); 133 } 134 135 // Does "this" end with "x" 136 bool ends_with(const StringPiece& x) const { 137 return ((length_ >= x.length_) && 138 (wordmemcmp(ptr_ + (length_-x.length_), x.ptr_, x.length_) == 0)); 139 } 140 141 iterator begin() const { return ptr_; } 142 iterator end() const { return ptr_ + length_; } 143 const_reverse_iterator rbegin() const { 144 return const_reverse_iterator(ptr_ + length_); 145 } 146 const_reverse_iterator rend() const { 147 return const_reverse_iterator(ptr_); 148 } 149 150 size_type max_size() const { return length_; } 151 size_type capacity() const { return length_; } 152 153 size_type copy(char* buf, size_type n, size_type pos = 0) const; 154 155 size_type find(const StringPiece& s, size_type pos = 0) const; 156 size_type find(char c, size_type pos = 0) const; 157 size_type rfind(const StringPiece& s, size_type pos = npos) const; 158 size_type rfind(char c, size_type pos = npos) const; 159 160 size_type find_first_of(const StringPiece& s, size_type pos = 0) const; 161 size_type find_first_of(char c, size_type pos = 0) const { 162 return find(c, pos); 163 } 164 size_type find_first_not_of(const StringPiece& s, size_type pos = 0) const; 165 size_type find_first_not_of(char c, size_type pos = 0) const; 166 size_type find_last_of(const StringPiece& s, size_type pos = npos) const; 167 size_type find_last_of(char c, size_type pos = npos) const { 168 return rfind(c, pos); 169 } 170 size_type find_last_not_of(const StringPiece& s, size_type pos = npos) const; 171 size_type find_last_not_of(char c, size_type pos = npos) const; 172 173 StringPiece substr(size_type pos, size_type n = npos) const; 174 175 static int wordmemcmp(const char* p, const char* p2, size_type N) { 176 return memcmp(p, p2, N); 177 } 178 179 // kati specific functions will follow. 180 181 char get(size_type i) const { return i < length_ ? ptr_[i] : 0; } 182 183 private: 184 const char* ptr_; 185 size_type length_; 186 }; 187 188 bool operator==(const StringPiece& x, const StringPiece& y); 189 190 inline bool operator!=(const StringPiece& x, const StringPiece& y) { 191 return !(x == y); 192 } 193 194 inline bool operator<(const StringPiece& x, const StringPiece& y) { 195 const int r = StringPiece::wordmemcmp( 196 x.data(), y.data(), (x.size() < y.size() ? x.size() : y.size())); 197 return ((r < 0) || ((r == 0) && (x.size() < y.size()))); 198 } 199 200 inline bool operator>(const StringPiece& x, const StringPiece& y) { 201 return y < x; 202 } 203 204 inline bool operator<=(const StringPiece& x, const StringPiece& y) { 205 return !(x > y); 206 } 207 208 inline bool operator>=(const StringPiece& x, const StringPiece& y) { 209 return !(x < y); 210 } 211 212 namespace std { 213 template<> struct hash<StringPiece> { 214 size_t operator()(const StringPiece& s) const { 215 size_t result = 0; 216 for (char c : s) { 217 result = (result * 131) + c; 218 } 219 return result; 220 } 221 }; 222 223 } 224 225 #define SPF(s) static_cast<int>((s).size()), (s).data() 226 227 #endif // BASE_STRING_PIECE_H_ 228
