license.bot | f003cfe | 2008-08-24 09:55:55 +0900 | [diff] [blame^] | 1 | // Copyright (c) 2006-2008 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. |
initial.commit | 3f4a732 | 2008-07-27 06:49:38 +0900 | [diff] [blame] | 4 | // Copied from strings/stringpiece.cc with modifications |
| 5 | |
| 6 | #include <algorithm> |
| 7 | #include <iostream> |
| 8 | |
| 9 | #include "base/string_piece.h" |
| 10 | |
| 11 | typedef StringPiece::size_type size_type; |
| 12 | |
| 13 | std::ostream& operator<<(std::ostream& o, const StringPiece& piece) { |
| 14 | o.write(piece.data(), static_cast<std::streamsize>(piece.size())); |
| 15 | return o; |
| 16 | } |
| 17 | |
| 18 | bool operator==(const StringPiece& x, const StringPiece& y) { |
| 19 | if (x.size() != y.size()) |
| 20 | return false; |
| 21 | |
| 22 | return StringPiece::wordmemcmp(x.data(), y.data(), x.size()) == 0; |
| 23 | } |
| 24 | |
| 25 | void StringPiece::CopyToString(std::string* target) const { |
| 26 | target->assign(!empty() ? data() : "", size()); |
| 27 | } |
| 28 | |
| 29 | void StringPiece::AppendToString(std::string* target) const { |
| 30 | if (!empty()) |
| 31 | target->append(data(), size()); |
| 32 | } |
| 33 | |
| 34 | size_type StringPiece::copy(char* buf, size_type n, size_type pos) const { |
| 35 | size_type ret = std::min(length_ - pos, n); |
| 36 | memcpy(buf, ptr_ + pos, ret); |
| 37 | return ret; |
| 38 | } |
| 39 | |
| 40 | size_type StringPiece::find(const StringPiece& s, size_type pos) const { |
| 41 | if (pos > length_) |
| 42 | return npos; |
| 43 | |
| 44 | const char* result = std::search(ptr_ + pos, ptr_ + length_, |
| 45 | s.ptr_, s.ptr_ + s.length_); |
| 46 | const size_type xpos = result - ptr_; |
| 47 | return xpos + s.length_ <= length_ ? xpos : npos; |
| 48 | } |
| 49 | |
| 50 | size_type StringPiece::find(char c, size_type pos) const { |
| 51 | if (pos >= length_) |
| 52 | return npos; |
| 53 | |
| 54 | const char* result = std::find(ptr_ + pos, ptr_ + length_, c); |
| 55 | return result != ptr_ + length_ ? result - ptr_ : npos; |
| 56 | } |
| 57 | |
| 58 | size_type StringPiece::rfind(const StringPiece& s, size_type pos) const { |
| 59 | if (length_ < s.length_) |
| 60 | return npos; |
| 61 | |
| 62 | if (s.empty()) |
| 63 | return std::min(length_, pos); |
| 64 | |
| 65 | const char* last = ptr_ + std::min(length_ - s.length_, pos) + s.length_; |
| 66 | const char* result = std::find_end(ptr_, last, s.ptr_, s.ptr_ + s.length_); |
| 67 | return result != last ? result - ptr_ : npos; |
| 68 | } |
| 69 | |
| 70 | size_type StringPiece::rfind(char c, size_type pos) const { |
| 71 | if (length_ == 0) |
| 72 | return npos; |
| 73 | |
| 74 | for (size_type i = std::min(pos, length_ - 1); ; --i) { |
| 75 | if (ptr_[i] == c) |
| 76 | return i; |
| 77 | if (i == 0) |
| 78 | break; |
| 79 | } |
| 80 | return npos; |
| 81 | } |
| 82 | |
| 83 | // For each character in characters_wanted, sets the index corresponding |
| 84 | // to the ASCII code of that character to 1 in table. This is used by |
| 85 | // the find_.*_of methods below to tell whether or not a character is in |
| 86 | // the lookup table in constant time. |
| 87 | // The argument `table' must be an array that is large enough to hold all |
| 88 | // the possible values of an unsigned char. Thus it should be be declared |
| 89 | // as follows: |
| 90 | // bool table[UCHAR_MAX + 1] |
| 91 | static inline void BuildLookupTable(const StringPiece& characters_wanted, |
| 92 | bool* table) { |
| 93 | const size_type length = characters_wanted.length(); |
| 94 | const char* const data = characters_wanted.data(); |
| 95 | for (size_type i = 0; i < length; ++i) { |
| 96 | table[static_cast<unsigned char>(data[i])] = true; |
| 97 | } |
| 98 | } |
| 99 | |
| 100 | size_type StringPiece::find_first_of(const StringPiece& s, |
| 101 | size_type pos) const { |
| 102 | if (length_ == 0 || s.length_ == 0) |
| 103 | return npos; |
| 104 | |
| 105 | // Avoid the cost of BuildLookupTable() for a single-character search. |
| 106 | if (s.length_ == 1) |
| 107 | return find_first_of(s.ptr_[0], pos); |
| 108 | |
| 109 | bool lookup[UCHAR_MAX + 1] = { false }; |
| 110 | BuildLookupTable(s, lookup); |
| 111 | for (size_type i = pos; i < length_; ++i) { |
| 112 | if (lookup[static_cast<unsigned char>(ptr_[i])]) { |
| 113 | return i; |
| 114 | } |
| 115 | } |
| 116 | return npos; |
| 117 | } |
| 118 | |
| 119 | size_type StringPiece::find_first_not_of(const StringPiece& s, |
| 120 | size_type pos) const { |
| 121 | if (length_ == 0) |
| 122 | return npos; |
| 123 | |
| 124 | if (s.length_ == 0) |
| 125 | return 0; |
| 126 | |
| 127 | // Avoid the cost of BuildLookupTable() for a single-character search. |
| 128 | if (s.length_ == 1) |
| 129 | return find_first_not_of(s.ptr_[0], pos); |
| 130 | |
| 131 | bool lookup[UCHAR_MAX + 1] = { false }; |
| 132 | BuildLookupTable(s, lookup); |
| 133 | for (size_type i = pos; i < length_; ++i) { |
| 134 | if (!lookup[static_cast<unsigned char>(ptr_[i])]) { |
| 135 | return i; |
| 136 | } |
| 137 | } |
| 138 | return npos; |
| 139 | } |
| 140 | |
| 141 | size_type StringPiece::find_first_not_of(char c, size_type pos) const { |
| 142 | if (length_ == 0) |
| 143 | return npos; |
| 144 | |
| 145 | for (; pos < length_; ++pos) { |
| 146 | if (ptr_[pos] != c) { |
| 147 | return pos; |
| 148 | } |
| 149 | } |
| 150 | return npos; |
| 151 | } |
| 152 | |
| 153 | size_type StringPiece::find_last_of(const StringPiece& s, size_type pos) const { |
| 154 | if (length_ == 0 || s.length_ == 0) |
| 155 | return npos; |
| 156 | |
| 157 | // Avoid the cost of BuildLookupTable() for a single-character search. |
| 158 | if (s.length_ == 1) |
| 159 | return find_last_of(s.ptr_[0], pos); |
| 160 | |
| 161 | bool lookup[UCHAR_MAX + 1] = { false }; |
| 162 | BuildLookupTable(s, lookup); |
| 163 | for (size_type i = std::min(pos, length_ - 1); ; --i) { |
| 164 | if (lookup[static_cast<unsigned char>(ptr_[i])]) |
| 165 | return i; |
| 166 | if (i == 0) |
| 167 | break; |
| 168 | } |
| 169 | return npos; |
| 170 | } |
| 171 | |
| 172 | size_type StringPiece::find_last_not_of(const StringPiece& s, |
| 173 | size_type pos) const { |
| 174 | if (length_ == 0) |
| 175 | return npos; |
| 176 | |
| 177 | size_type i = std::min(pos, length_ - 1); |
| 178 | if (s.length_ == 0) |
| 179 | return i; |
| 180 | |
| 181 | // Avoid the cost of BuildLookupTable() for a single-character search. |
| 182 | if (s.length_ == 1) |
| 183 | return find_last_not_of(s.ptr_[0], pos); |
| 184 | |
| 185 | bool lookup[UCHAR_MAX + 1] = { false }; |
| 186 | BuildLookupTable(s, lookup); |
| 187 | for (; ; --i) { |
| 188 | if (!lookup[static_cast<unsigned char>(ptr_[i])]) |
| 189 | return i; |
| 190 | if (i == 0) |
| 191 | break; |
| 192 | } |
| 193 | return npos; |
| 194 | } |
| 195 | |
| 196 | size_type StringPiece::find_last_not_of(char c, size_type pos) const { |
| 197 | if (length_ == 0) |
| 198 | return npos; |
| 199 | |
| 200 | for (size_type i = std::min(pos, length_ - 1); ; --i) { |
| 201 | if (ptr_[i] != c) |
| 202 | return i; |
| 203 | if (i == 0) |
| 204 | break; |
| 205 | } |
| 206 | return npos; |
| 207 | } |
| 208 | |
| 209 | StringPiece StringPiece::substr(size_type pos, size_type n) const { |
| 210 | if (pos > length_) pos = length_; |
| 211 | if (n > length_ - pos) n = length_ - pos; |
| 212 | return StringPiece(ptr_ + pos, n); |
| 213 | } |
| 214 | |
| 215 | const StringPiece::size_type StringPiece::npos = size_type(-1); |
license.bot | f003cfe | 2008-08-24 09:55:55 +0900 | [diff] [blame^] | 216 | |