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 #include "packet/fragmenting_inserter.h" 18 19 #include "os/log.h" 20 21 namespace bluetooth { 22 namespace packet { 23 24 FragmentingInserter::FragmentingInserter(size_t mtu, 25 std::back_insert_iterator<std::vector<std::unique_ptr<RawBuilder>>> iterator) 26 : BitInserter(to_construct_bit_inserter_), mtu_(mtu), curr_packet_(std::make_unique<RawBuilder>(mtu)), 27 iterator_(iterator) {} 28 29 void FragmentingInserter::insert_bits(uint8_t byte, size_t num_bits) { 30 ASSERT(curr_packet_ != nullptr); 31 size_t total_bits = num_bits + num_saved_bits_; 32 uint16_t new_value = static_cast<uint8_t>(saved_bits_) | (static_cast<uint16_t>(byte) << num_saved_bits_); 33 if (total_bits >= 8) { 34 uint8_t new_byte = static_cast<uint8_t>(new_value); 35 on_byte(new_byte); 36 curr_packet_->AddOctets1(new_byte); 37 if (curr_packet_->size() >= mtu_) { 38 iterator_ = std::move(curr_packet_); 39 curr_packet_ = std::make_unique<RawBuilder>(mtu_); 40 } 41 total_bits -= 8; 42 new_value = new_value >> 8; 43 } 44 num_saved_bits_ = total_bits; 45 uint8_t mask = static_cast<uint8_t>(0xff) >> (8 - num_saved_bits_); 46 saved_bits_ = static_cast<uint8_t>(new_value) & mask; 47 } 48 49 void FragmentingInserter::finalize() { 50 if (curr_packet_->size() != 0) { 51 iterator_ = std::move(curr_packet_); 52 } 53 curr_packet_.reset(); 54 } 55 56 } // namespace packet 57 } // namespace bluetooth 58