| // |
| // 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 "h4_packetizer.h" |
| |
| #define LOG_TAG "h4_packetizer" |
| |
| #include <dlfcn.h> |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <log/log.h> |
| #include <sys/uio.h> |
| #include <unistd.h> |
| |
| namespace test_vendor_lib { |
| namespace hci { |
| constexpr size_t H4Packetizer::COMMAND_PREAMBLE_SIZE; |
| constexpr size_t H4Packetizer::COMMAND_LENGTH_OFFSET; |
| constexpr size_t H4Packetizer::ACL_PREAMBLE_SIZE; |
| constexpr size_t H4Packetizer::ACL_LENGTH_OFFSET; |
| constexpr size_t H4Packetizer::SCO_PREAMBLE_SIZE; |
| constexpr size_t H4Packetizer::SCO_LENGTH_OFFSET; |
| constexpr size_t H4Packetizer::EVENT_PREAMBLE_SIZE; |
| constexpr size_t H4Packetizer::EVENT_LENGTH_OFFSET; |
| |
| constexpr size_t H4Packetizer::PREAMBLE_SIZE_MAX; |
| |
| size_t H4Packetizer::HciGetPacketLengthForType(hci::PacketType type, const uint8_t* preamble) { |
| static const size_t packet_length_offset[static_cast<size_t>(hci::PacketType::EVENT) + 1] = { |
| 0, |
| H4Packetizer::COMMAND_LENGTH_OFFSET, |
| H4Packetizer::ACL_LENGTH_OFFSET, |
| H4Packetizer::SCO_LENGTH_OFFSET, |
| H4Packetizer::EVENT_LENGTH_OFFSET, |
| }; |
| |
| size_t offset = packet_length_offset[static_cast<size_t>(type)]; |
| if (type != hci::PacketType::ACL) return preamble[offset]; |
| return (((preamble[offset + 1]) << 8) | preamble[offset]); |
| } |
| |
| H4Packetizer::H4Packetizer(int fd, PacketReadCallback command_cb, PacketReadCallback event_cb, |
| PacketReadCallback acl_cb, PacketReadCallback sco_cb) |
| : uart_fd_(fd), command_cb_(command_cb), event_cb_(event_cb), acl_cb_(acl_cb), sco_cb_(sco_cb) {} |
| |
| size_t H4Packetizer::Send(uint8_t type, const uint8_t* data, size_t length) { |
| struct iovec iov[] = {{&type, sizeof(type)}, {const_cast<uint8_t*>(data), length}}; |
| ssize_t ret = 0; |
| do { |
| ret = TEMP_FAILURE_RETRY(writev(uart_fd_, iov, sizeof(iov) / sizeof(iov[0]))); |
| } while (-1 == ret && EAGAIN == errno); |
| |
| if (ret == -1) { |
| ALOGE("%s error writing to UART (%s)", __func__, strerror(errno)); |
| } else if (ret < static_cast<ssize_t>(length + 1)) { |
| ALOGE("%s: %d / %d bytes written - something went wrong...", __func__, static_cast<int>(ret), |
| static_cast<int>(length + 1)); |
| } |
| return ret; |
| } |
| |
| void H4Packetizer::OnPacketReady() { |
| ALOGE("%s: before switch", __func__); |
| switch (hci_packet_type_) { |
| case hci::PacketType::COMMAND: |
| command_cb_(packet_); |
| break; |
| case hci::PacketType::ACL: |
| acl_cb_(packet_); |
| break; |
| case hci::PacketType::SCO: |
| sco_cb_(packet_); |
| break; |
| case hci::PacketType::EVENT: |
| event_cb_(packet_); |
| break; |
| default: |
| LOG_ALWAYS_FATAL("%s: Unimplemented packet type %d", __func__, static_cast<int>(hci_packet_type_)); |
| } |
| // Get ready for the next type byte. |
| hci_packet_type_ = hci::PacketType::UNKNOWN; |
| } |
| |
| void H4Packetizer::OnDataReady(int fd) { |
| if (hci_packet_type_ == hci::PacketType::UNKNOWN) { |
| uint8_t buffer[1] = {0}; |
| ssize_t bytes_read = TEMP_FAILURE_RETRY(read(fd, buffer, 1)); |
| if (bytes_read != 1) { |
| if (bytes_read == 0) { |
| ALOGI("%s: Nothing ready, will retry!", __func__); |
| return; |
| } else if (bytes_read < 0) { |
| if (errno == EAGAIN) { |
| // No data, try again later. |
| return; |
| } else { |
| LOG_ALWAYS_FATAL("%s: Read packet type error: %s", __func__, strerror(errno)); |
| } |
| } else { |
| LOG_ALWAYS_FATAL("%s: More bytes read than expected (%u)!", __func__, static_cast<unsigned int>(bytes_read)); |
| } |
| } |
| hci_packet_type_ = static_cast<hci::PacketType>(buffer[0]); |
| if (hci_packet_type_ != hci::PacketType::ACL && hci_packet_type_ != hci::PacketType::SCO && |
| hci_packet_type_ != hci::PacketType::COMMAND && hci_packet_type_ != hci::PacketType::EVENT) { |
| LOG_ALWAYS_FATAL("%s: Unimplemented packet type %d", __func__, static_cast<int>(hci_packet_type_)); |
| } |
| } else { |
| static const size_t preamble_size[static_cast<size_t>(hci::PacketType::EVENT) + 1] = { |
| 0, |
| H4Packetizer::COMMAND_PREAMBLE_SIZE, |
| H4Packetizer::ACL_PREAMBLE_SIZE, |
| H4Packetizer::SCO_PREAMBLE_SIZE, |
| H4Packetizer::EVENT_PREAMBLE_SIZE, |
| }; |
| |
| switch (state_) { |
| case HCI_PREAMBLE: { |
| size_t preamble_bytes = preamble_size[static_cast<size_t>(hci_packet_type_)]; |
| ssize_t bytes_read = TEMP_FAILURE_RETRY(read(fd, preamble_ + bytes_read_, preamble_bytes - bytes_read_)); |
| if (bytes_read == 0) { |
| ALOGE("%s: Will try again to read the header!", __func__); |
| return; |
| } |
| if (bytes_read < 0) { |
| // Ignore temporary failures. |
| if (errno == EAGAIN) { |
| return; |
| } |
| LOG_ALWAYS_FATAL("%s: Read header error: %s", __func__, strerror(errno)); |
| } |
| bytes_read_ += bytes_read; |
| if (bytes_read_ == preamble_bytes) { |
| size_t packet_length = HciGetPacketLengthForType(hci_packet_type_, preamble_); |
| packet_.resize(preamble_bytes + packet_length); |
| memcpy(packet_.data(), preamble_, preamble_bytes); |
| ALOGI("%s: Read a preamble of size %d length %d %0x %0x %0x", __func__, static_cast<int>(bytes_read_), |
| static_cast<int>(packet_length), preamble_[0], preamble_[1], preamble_[2]); |
| bytes_remaining_ = packet_length; |
| if (bytes_remaining_ == 0) { |
| OnPacketReady(); |
| state_ = HCI_PREAMBLE; |
| bytes_read_ = 0; |
| } else { |
| state_ = HCI_PAYLOAD; |
| bytes_read_ = 0; |
| } |
| } |
| break; |
| } |
| |
| case HCI_PAYLOAD: { |
| size_t preamble_bytes = preamble_size[static_cast<size_t>(hci_packet_type_)]; |
| ssize_t bytes_read = |
| TEMP_FAILURE_RETRY(read(fd, packet_.data() + preamble_bytes + bytes_read_, bytes_remaining_)); |
| if (bytes_read == 0) { |
| ALOGI("%s: Will try again to read the payload!", __func__); |
| return; |
| } |
| if (bytes_read < 0) { |
| // Ignore temporary failures. |
| if (errno == EAGAIN) { |
| return; |
| } |
| LOG_ALWAYS_FATAL("%s: Read payload error: %s", __func__, strerror(errno)); |
| } |
| bytes_remaining_ -= bytes_read; |
| bytes_read_ += bytes_read; |
| if (bytes_remaining_ == 0) { |
| OnPacketReady(); |
| state_ = HCI_PREAMBLE; |
| bytes_read_ = 0; |
| } |
| break; |
| } |
| } |
| } |
| } |
| |
| } // namespace hci |
| } // namespace test_vendor_lib |