1 /* 2 * Copyright (C) 2017 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include "text/Utf8Iterator.h" 18 19 #include "android-base/logging.h" 20 #include "utils/Unicode.h" 21 22 using ::android::StringPiece; 23 24 namespace aapt { 25 namespace text { 26 27 Utf8Iterator::Utf8Iterator(const StringPiece& str) 28 : str_(str), current_pos_(0), next_pos_(0), current_codepoint_(0) { 29 DoNext(); 30 } 31 32 void Utf8Iterator::DoNext() { 33 current_pos_ = next_pos_; 34 int32_t result = utf32_from_utf8_at(str_.data(), str_.size(), current_pos_, &next_pos_); 35 if (result == -1) { 36 current_codepoint_ = 0u; 37 } else { 38 current_codepoint_ = static_cast<char32_t>(result); 39 } 40 } 41 42 bool Utf8Iterator::HasNext() const { 43 return current_codepoint_ != 0; 44 } 45 46 size_t Utf8Iterator::Position() const { 47 return current_pos_; 48 } 49 50 void Utf8Iterator::Skip(int amount) { 51 while (amount > 0 && HasNext()) { 52 Next(); 53 --amount; 54 } 55 } 56 57 char32_t Utf8Iterator::Next() { 58 CHECK(HasNext()) << "Next() called after iterator exhausted"; 59 char32_t result = current_codepoint_; 60 DoNext(); 61 return result; 62 } 63 64 } // namespace text 65 } // namespace aapt 66
