1 /* 2 * Copyright 2018 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 #include <iterator> 22 #include <memory> 23 #include <vector> 24 25 #include "base_packet_builder.h" 26 #include "types/address.h" 27 #include "types/class_of_device.h" 28 29 namespace test_vendor_lib { 30 namespace packets { 31 32 // Abstract base class that is subclassed to build specifc packets. 33 // The template parameter little_endian controls the generation of insert(). 34 template <bool little_endian> 35 class PacketBuilder : public BasePacketBuilder { 36 public: 37 PacketBuilder() = default; 38 virtual ~PacketBuilder() = default; 39 40 // Classes which need fragmentation should define a function like this: 41 // std::forward_list<DerivedBuilder>& Fragment(size_t max_size); 42 43 protected: 44 // Write sizeof(FixedWidthIntegerType) bytes using the iterator 45 template <typename FixedWidthIntegerType, 46 typename std::enable_if<std::is_integral<FixedWidthIntegerType>::value, int>::type = 0> insert(FixedWidthIntegerType value,std::back_insert_iterator<std::vector<uint8_t>> it)47 void insert(FixedWidthIntegerType value, std::back_insert_iterator<std::vector<uint8_t>> it) const { 48 for (size_t i = 0; i < sizeof(FixedWidthIntegerType); i++) { 49 if (little_endian == true) { 50 *it = static_cast<uint8_t>(value >> (i * 8)); 51 } else { 52 *it = static_cast<uint8_t>(value >> ((sizeof(FixedWidthIntegerType) - i - 1) * 8)); 53 } 54 it++; 55 } 56 } 57 58 // Specialized insert that allows inserting enums without casting 59 template <typename Enum, typename std::enable_if<std::is_enum_v<Enum>, int>::type = 0> insert(Enum value,std::back_insert_iterator<std::vector<uint8_t>> it)60 inline void insert(Enum value, std::back_insert_iterator<std::vector<uint8_t>> it) const { 61 using enum_type = typename std::underlying_type_t<Enum>; 62 static_assert(std::is_unsigned_v<enum_type>, "Enum type is signed. Did you forget to specify the enum size?"); 63 insert<enum_type>(static_cast<enum_type>(value), it); 64 } 65 66 // Write a vector of FixedWidthIntegerType using the iterator 67 template <typename FixedWidthIntegerType> insert_vector(const std::vector<FixedWidthIntegerType> & vec,std::back_insert_iterator<std::vector<uint8_t>> it)68 void insert_vector(const std::vector<FixedWidthIntegerType>& vec, 69 std::back_insert_iterator<std::vector<uint8_t>> it) const { 70 static_assert(std::is_integral<FixedWidthIntegerType>::value, 71 "PacketBuilder::insert requires an integral type vector."); 72 for (const auto& element : vec) { 73 insert(element, it); 74 } 75 } 76 insert_address(const Address & addr,std::back_insert_iterator<std::vector<uint8_t>> it)77 void insert_address(const Address& addr, std::back_insert_iterator<std::vector<uint8_t>> it) const { 78 for (const auto& element : addr.address) { 79 insert(element, it); 80 } 81 } 82 insert_class_of_device(const ClassOfDevice & cod,std::back_insert_iterator<std::vector<uint8_t>> it)83 void insert_class_of_device(const ClassOfDevice& cod, std::back_insert_iterator<std::vector<uint8_t>> it) const { 84 for (const auto& element : cod.cod) { 85 insert(element, it); 86 } 87 } 88 }; 89 90 } // namespace packets 91 } // namespace test_vendor_lib 92