1 /* 2 * Copyright 2019 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 #pragma once 18 19 #include <cstdint> 20 #include <forward_list> 21 22 #include "packet/view.h" 23 24 namespace bluetooth { 25 namespace packet { 26 27 // Templated Iterator for endianness 28 template <bool little_endian> 29 class Iterator : public std::iterator<std::random_access_iterator_tag, uint8_t> { 30 public: 31 Iterator(std::forward_list<View> data, size_t offset); 32 Iterator(const Iterator& itr) = default; 33 virtual ~Iterator() = default; 34 35 // All addition and subtraction operators are unbounded. 36 Iterator operator+(int offset); 37 Iterator& operator+=(int offset); 38 Iterator operator++(int); 39 Iterator& operator++(); 40 41 Iterator operator-(int offset); 42 int operator-(Iterator& itr); 43 Iterator& operator-=(int offset); 44 Iterator operator--(int); 45 Iterator& operator--(); 46 47 Iterator& operator=(const Iterator& itr); 48 49 bool operator!=(const Iterator& itr) const; 50 bool operator==(const Iterator& itr) const; 51 52 bool operator<(const Iterator& itr) const; 53 bool operator>(const Iterator& itr) const; 54 55 bool operator<=(const Iterator& itr) const; 56 bool operator>=(const Iterator& itr) const; 57 58 uint8_t operator*() const; 59 uint8_t operator->() const; 60 61 size_t NumBytesRemaining() const; 62 63 // Get the next sizeof(FixedWidthPODType) bytes and return the filled type 64 template <typename FixedWidthPODType> extract()65 FixedWidthPODType extract() { 66 static_assert(std::is_pod<FixedWidthPODType>::value, "Iterator::extract requires an fixed type."); 67 FixedWidthPODType extracted_value; 68 uint8_t* value_ptr = (uint8_t*)&extracted_value; 69 70 for (size_t i = 0; i < sizeof(FixedWidthPODType); i++) { 71 size_t index = (little_endian ? i : sizeof(FixedWidthPODType) - i - 1); 72 value_ptr[index] = *((*this)++); 73 } 74 return extracted_value; 75 } 76 77 private: 78 std::forward_list<View> data_; 79 size_t index_; 80 size_t length_; 81 }; 82 83 } // namespace packet 84 } // namespace bluetooth 85