| /* |
| * Copyright (C) 2017 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #ifndef LIBTEXTCLASSIFIER_UTIL_STRINGS_STRINGPIECE_H_ |
| #define LIBTEXTCLASSIFIER_UTIL_STRINGS_STRINGPIECE_H_ |
| |
| #include <stddef.h> |
| |
| #include <string> |
| |
| namespace libtextclassifier { |
| |
| // Read-only "view" of a piece of data. Does not own the underlying data. |
| class StringPiece { |
| public: |
| StringPiece() : StringPiece(nullptr, 0) {} |
| |
| StringPiece(const char *str) // NOLINT(runtime/explicit) |
| : start_(str), size_(strlen(str)) {} |
| |
| StringPiece(const char *start, size_t size) |
| : start_(start), size_(size) {} |
| |
| // Intentionally no "explicit" keyword: in function calls, we want strings to |
| // be converted to StringPiece implicitly. |
| StringPiece(const std::string &s) // NOLINT(runtime/explicit) |
| : StringPiece(s.data(), s.size()) {} |
| |
| StringPiece(const std::string &s, int offset, int len) |
| : StringPiece(s.data() + offset, len) {} |
| |
| char operator[](size_t i) const { return start_[i]; } |
| |
| // Returns start address of underlying data. |
| const char *data() const { return start_; } |
| |
| // Returns number of bytes of underlying data. |
| size_t size() const { return size_; } |
| size_t length() const { return size_; } |
| |
| // Returns a std::string containing a copy of the underlying data. |
| std::string ToString() const { |
| return std::string(data(), size()); |
| } |
| |
| private: |
| const char *start_; // Not owned. |
| size_t size_; |
| }; |
| |
| } // namespace libtextclassifier |
| |
| #endif // LIBTEXTCLASSIFIER_UTIL_STRINGS_STRINGPIECE_H_ |