1// 2// Copyright 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 "hci_packetizer.h" 18 19#define LOG_TAG "android.hardware.bluetooth.hci_packetizer" 20#include <android-base/logging.h> 21#include <utils/Log.h> 22 23#include <dlfcn.h> 24#include <fcntl.h> 25 26namespace { 27 28const size_t preamble_size_for_type[] = { 29 0, HCI_COMMAND_PREAMBLE_SIZE, HCI_ACL_PREAMBLE_SIZE, HCI_SCO_PREAMBLE_SIZE, 30 HCI_EVENT_PREAMBLE_SIZE}; 31const size_t packet_length_offset_for_type[] = { 32 0, HCI_LENGTH_OFFSET_CMD, HCI_LENGTH_OFFSET_ACL, HCI_LENGTH_OFFSET_SCO, 33 HCI_LENGTH_OFFSET_EVT}; 34 35size_t HciGetPacketLengthForType(HciPacketType type, const uint8_t* preamble) { 36 size_t offset = packet_length_offset_for_type[type]; 37 if (type != HCI_PACKET_TYPE_ACL_DATA) return preamble[offset]; 38 return (((preamble[offset + 1]) << 8) | preamble[offset]); 39} 40 41} // namespace 42 43namespace android { 44namespace hardware { 45namespace bluetooth { 46namespace hci { 47 48const hidl_vec<uint8_t>& HciPacketizer::GetPacket() const { return packet_; } 49 50void HciPacketizer::CbHciPacket(uint8_t *data, size_t len) { 51 packet_.setToExternal(data, len); 52 packet_ready_cb_(); 53} 54 55void HciPacketizer::OnDataReady(int fd, HciPacketType packet_type) { 56 switch (state_) { 57 case HCI_PREAMBLE: { 58 size_t bytes_read = TEMP_FAILURE_RETRY( 59 read(fd, preamble_ + bytes_read_, 60 preamble_size_for_type[packet_type] - bytes_read_)); 61 CHECK(bytes_read > 0); 62 bytes_read_ += bytes_read; 63 if (bytes_read_ == preamble_size_for_type[packet_type]) { 64 size_t packet_length = 65 HciGetPacketLengthForType(packet_type, preamble_); 66 packet_.resize(preamble_size_for_type[packet_type] + packet_length); 67 memcpy(packet_.data(), preamble_, preamble_size_for_type[packet_type]); 68 bytes_remaining_ = packet_length; 69 state_ = HCI_PAYLOAD; 70 bytes_read_ = 0; 71 } 72 break; 73 } 74 75 case HCI_PAYLOAD: { 76 size_t bytes_read = TEMP_FAILURE_RETRY(read( 77 fd, 78 packet_.data() + preamble_size_for_type[packet_type] + bytes_read_, 79 bytes_remaining_)); 80 CHECK(bytes_read > 0); 81 bytes_remaining_ -= bytes_read; 82 bytes_read_ += bytes_read; 83 if (bytes_remaining_ == 0) { 84 packet_ready_cb_(); 85 state_ = HCI_PREAMBLE; 86 bytes_read_ = 0; 87 } 88 break; 89 } 90 } 91} 92 93} // namespace hci 94} // namespace bluetooth 95} // namespace hardware 96} // namespace android 97