| /* |
| * 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_LANG_ID_CUSTOM_TOKENIZER_H_ |
| #define LIBTEXTCLASSIFIER_LANG_ID_CUSTOM_TOKENIZER_H_ |
| |
| #include <cstddef> |
| #include <string> |
| |
| #include "lang_id/light-sentence.h" |
| |
| namespace libtextclassifier { |
| namespace nlp_core { |
| namespace lang_id { |
| |
| // Perform custom tokenization of text. Customized for the language |
| // identification project. Currently (Sep 15, 2016) we tokenize on space, |
| // newline, and tab, ignore all empty tokens, and (for each of the remaining |
| // tokens) prepend "^" (special token begin marker) and append "$" (special |
| // token end marker). |
| // |
| // Tokens are stored into the words of the LightSentence *sentence. |
| void TokenizeTextForLangId(const std::string &text, LightSentence *sentence); |
| |
| // Returns a pointer "end" inside [data, data + size) such that the prefix from |
| // [data, end) is the largest one that does not contain '\0' and offers the |
| // following guarantee: if one starts with |
| // |
| // curr = text.data() |
| // |
| // and keeps executing |
| // |
| // curr += utils::GetNumBytesForNonZeroUTF8Char(curr) |
| // |
| // one would eventually reach curr == end (the pointer returned by this |
| // function) without accessing data outside the std::string. This guards |
| // against scenarios like a broken UTF-8 string which has only e.g., the first 2 |
| // bytes from a 3-byte UTF8 sequence. |
| const char *GetSafeEndOfString(const char *data, size_t size); |
| |
| static inline const char *GetSafeEndOfString(const std::string &text) { |
| return GetSafeEndOfString(text.data(), text.size()); |
| } |
| |
| } // namespace lang_id |
| } // namespace nlp_core |
| } // namespace libtextclassifier |
| |
| #endif // LIBTEXTCLASSIFIER_LANG_ID_CUSTOM_TOKENIZER_H_ |