// // Copyright 2017 The Android Open Source Project // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. // See the License for the specific language governing permissions and // limitations under the License. // #include "hci_packetizer.h" #define LOG_TAG "android.hardware.bluetooth.hci_packetizer" #include <android-base/logging.h> #include <utils/Log.h> #include <dlfcn.h> #include <fcntl.h> namespace { const size_t preamble_size_for_type[] = { 0, HCI_COMMAND_PREAMBLE_SIZE, HCI_ACL_PREAMBLE_SIZE, HCI_SCO_PREAMBLE_SIZE, HCI_EVENT_PREAMBLE_SIZE}; const size_t packet_length_offset_for_type[] = { 0, HCI_LENGTH_OFFSET_CMD, HCI_LENGTH_OFFSET_ACL, HCI_LENGTH_OFFSET_SCO, HCI_LENGTH_OFFSET_EVT}; size_t HciGetPacketLengthForType(HciPacketType type, const uint8_t* preamble) { size_t offset = packet_length_offset_for_type[type]; if (type != HCI_PACKET_TYPE_ACL_DATA) return preamble[offset]; return (((preamble[offset + 1]) << 8) | preamble[offset]); } } // namespace namespace android { namespace hardware { namespace bluetooth { namespace hci { const hidl_vec<uint8_t>& HciPacketizer::GetPacket() const { return packet_; } void HciPacketizer::OnDataReady(int fd, HciPacketType packet_type) { switch (state_) { case HCI_PREAMBLE: { size_t bytes_read = TEMP_FAILURE_RETRY( read(fd, preamble_ + bytes_read_, preamble_size_for_type[packet_type] - bytes_read_)); CHECK(bytes_read > 0); bytes_read_ += bytes_read; if (bytes_read_ == preamble_size_for_type[packet_type]) { size_t packet_length = HciGetPacketLengthForType(packet_type, preamble_); packet_.resize(preamble_size_for_type[packet_type] + packet_length); memcpy(packet_.data(), preamble_, preamble_size_for_type[packet_type]); bytes_remaining_ = packet_length; state_ = HCI_PAYLOAD; bytes_read_ = 0; } break; } case HCI_PAYLOAD: { size_t bytes_read = TEMP_FAILURE_RETRY(read( fd, packet_.data() + preamble_size_for_type[packet_type] + bytes_read_, bytes_remaining_)); CHECK(bytes_read > 0); bytes_remaining_ -= bytes_read; bytes_read_ += bytes_read; if (bytes_remaining_ == 0) { packet_ready_cb_(); state_ = HCI_PREAMBLE; bytes_read_ = 0; } break; } } } } // namespace hci } // namespace bluetooth } // namespace hardware } // namespace android