/* * Copyright (C) 2015, 2016 "IoT.bzh" * Author "Romain Forlot" <romain.forlot@iot.bzh> * * 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 "can-message.hpp" #include <cstring> #include "../binding/low-can-hat.hpp" /// /// @brief Class constructor /// /// Constructor about can_message_t class. /// can_message_t::can_message_t() : maxdlen_{0}, id_{0}, length_{0}, format_{can_message_format_t::INVALID}, rtr_flag_{false}, flags_{0}, timestamp_{0}, sub_id_{-1} {} can_message_t::can_message_t(uint8_t maxdlen, uint32_t id, uint8_t length, can_message_format_t format, bool rtr_flag, uint8_t flags, std::vector<uint8_t>& data, uint64_t timestamp) : maxdlen_{maxdlen}, id_{id}, length_{length}, format_{format}, rtr_flag_{rtr_flag}, flags_{flags}, data_{data}, timestamp_{timestamp}, sub_id_{-1} {} /// /// @brief Retrieve id_ member value. /// /// @return id_ class member /// uint32_t can_message_t::get_id() const { return id_; } int can_message_t::get_sub_id() const { return sub_id_; } /// /// @brief Retrieve RTR flag member. /// /// @return rtr_flags_ class member /// bool can_message_t::get_rtr_flag_() const { return rtr_flag_; } /// /// @brief Retrieve format_ member value. /// /// @return format_ class member. Default to INVALID. /// can_message_format_t can_message_t::get_format() const { if (format_ != can_message_format_t::STANDARD || format_ != can_message_format_t::EXTENDED) return can_message_format_t::INVALID; return format_; } /// /// @brief Retrieve flags_ member value. /// /// @return flags_ class member /// uint8_t can_message_t::get_flags() const { return flags_; } /// /// @brief Retrieve data_ member value. /// /// @return pointer to the first element /// of class member data_ /// const uint8_t* can_message_t::get_data() const { return data_.data(); } /// /// @brief Retrieve data_ member whole vector /// /// @return the vector as is /// const std::vector<uint8_t> can_message_t::get_data_vector() const { return data_; } /// /// @brief Retrieve length_ member value. /// /// @return length_ class member /// uint8_t can_message_t::get_length() const { return length_; } void can_message_t::set_sub_id(int sub_id) { sub_id_ = sub_id; } uint64_t can_message_t::get_timestamp() const { return timestamp_; } void can_message_t::set_timestamp(uint64_t timestamp) { timestamp_ = timestamp; } /// @brief Control whether the object is correctly initialized /// to be sent over the CAN bus /// /// @return True if object correctly initialized and false if not. bool can_message_t::is_correct_to_send() { if (id_ != 0 && length_ != 0 && format_ != can_message_format_t::INVALID) { int i; for(i=0;i<CAN_MESSAGE_SIZE;i++) if(data_[i] != 0) return true; } return false; } /// @brief Set format_ member value. /// /// Preferred way to initialize these members by using /// convert_from_canfd_frame method. /// /// @param[in] new_format - class member void can_message_t::set_format(const can_message_format_t new_format) { if(new_format == can_message_format_t::STANDARD || new_format == can_message_format_t::EXTENDED || new_format == can_message_format_t::INVALID) format_ = new_format; else ERROR("Can set format, wrong format chosen"); } /// @brief Take a canfd_frame struct to initialize class members /// /// This is the preferred way to initialize class members. /// /// @param[in] frame - canfd_frame to convert coming from a read of CAN socket /// @param[in] nbytes - bytes read from socket read operation. /// /// @return A can_message_t object fully initialized with canfd_frame values. can_message_t can_message_t::convert_from_frame(const struct canfd_frame& frame, size_t nbytes, uint64_t timestamp) { uint8_t maxdlen, length, flags = (uint8_t)NULL; uint32_t id; can_message_format_t format; bool rtr_flag; std::vector<uint8_t> data; switch(nbytes) { case CANFD_MTU: DEBUG("Got an CAN FD frame"); maxdlen = CANFD_MAX_DLEN; break; case CAN_MTU: DEBUG("Got a legacy CAN frame"); maxdlen = CAN_MAX_DLEN; break; default: ERROR("unsupported CAN frame"); break; } if (frame.can_id & CAN_ERR_FLAG) { format = can_message_format_t::INVALID; id = frame.can_id & (CAN_ERR_MASK|CAN_ERR_FLAG); } else if (frame.can_id & CAN_EFF_FLAG) { format = can_message_format_t::EXTENDED; id = frame.can_id & CAN_EFF_MASK; } else { format = can_message_format_t::STANDARD; id = frame.can_id & CAN_SFF_MASK; } /* Overwrite length_ if RTR flags is detected. * standard CAN frames may have RTR enabled. There are no ERR frames with RTR */ if (frame.can_id & CAN_RTR_FLAG) { rtr_flag = true; if(frame.len && frame.len <= CAN_MAX_DLC) { if(rtr_flag) length = frame.len& 0xF; else { length = (frame.len > maxdlen) ? maxdlen : frame.len; } } } else { length = (frame.len > maxdlen) ? maxdlen : frame.len; /* Flags field only present for CAN FD frames*/ if(maxdlen == CANFD_MAX_DLEN) flags = frame.flags & 0xF; if (data.capacity() < maxdlen) data.reserve(maxdlen); int i; data.clear(); /* maxdlen_ is now set at CAN_MAX_DLEN or CANFD_MAX_DLEN, respectively 8 and 64 bytes*/ for(i=0;i<maxdlen;i++) { data.push_back(frame.data[i]); }; DEBUG("Found id: %X, format: %X, length: %X, data %02X%02X%02X%02X%02X%02X%02X%02X", id, (uint8_t)format, length, data[0], data[1], data[2], data[3], data[4], data[5], data[6], data[7]); } return can_message_t(maxdlen, id, length, format, rtr_flag, flags, data, timestamp); } /// @brief Take a can_frame struct to initialize class members /// /// This is the preferred way to initialize class members. /// /// @param[in] frame - can_frame to convert coming from a read of CAN socket /// @param[in] nbytes - bytes read from socket read operation. /// /// @return A can_message_t object fully initialized with can_frame values. can_message_t can_message_t::convert_from_frame(const struct can_frame& frame, size_t nbytes, uint64_t timestamp) { uint8_t maxdlen, length, flags = (uint8_t)NULL; uint32_t id; can_message_format_t format; bool rtr_flag; std::vector<uint8_t> data; if(nbytes <= CAN_MTU) { DEBUG("Got a legacy CAN frame"); maxdlen = CAN_MAX_DLEN; } else { ERROR("unsupported CAN frame"); } if (frame.can_id & CAN_ERR_FLAG) { format = can_message_format_t::INVALID; id = frame.can_id & (CAN_ERR_MASK|CAN_ERR_FLAG); } else if (frame.can_id & CAN_EFF_FLAG) { format = can_message_format_t::EXTENDED; id = frame.can_id & CAN_EFF_MASK; } else { format = can_message_format_t::STANDARD; id = frame.can_id & CAN_SFF_MASK; } /* Overwrite length_ if RTR flags is detected. * standard CAN frames may have RTR enabled. There are no ERR frames with RTR */ if (frame.can_id & CAN_RTR_FLAG) { rtr_flag = true; if(frame.can_dlc && frame.can_dlc <= CAN_MAX_DLC) { if(rtr_flag) length = frame.can_dlc& 0xF; else { length = (frame.can_dlc > maxdlen) ? maxdlen : frame.can_dlc; } } } else { length = (frame.can_dlc > maxdlen) ? maxdlen : frame.can_dlc; if (data.capacity() < maxdlen) data.reserve(maxdlen); int i; data.clear(); /* maxdlen_ is now set at CAN_MAX_DLEN or CANFD_MAX_DLEN, respectively 8 and 64 bytes*/ for(i=0;i<maxdlen;i++) { data.push_back(frame.data[i]); }; // DEBUG("Found id: %X, format: %X, length: %X, data %02X%02X%02X%02X%02X%02X%02X%02X", // id, (uint8_t)format, length, data[0], data[1], data[2], data[3], data[4], data[5], data[6], data[7]); } return can_message_t(maxdlen, id, length, format, rtr_flag, flags, data, timestamp); } /// @brief Take all initialized class's members and build an /// canfd_frame struct that can be use to send a CAN message over /// the bus. /// /// @return canfd_frame struct built from class members. struct canfd_frame can_message_t::convert_to_canfd_frame() { canfd_frame frame; if(is_correct_to_send()) { frame.can_id = get_id(); frame.len = get_length(); ::memcpy(frame.data, get_data(), length_); } else ERROR("can_message_t not correctly initialized to be sent"); return frame; } /// @brief Take all initialized class's members and build an /// can_frame struct that can be use to send a CAN message over /// the bus. /// /// @return can_frame struct built from class members. struct can_frame can_message_t::convert_to_can_frame() { can_frame frame; if(is_correct_to_send()) { frame.can_id = get_id(); frame.can_dlc = get_length(); ::memcpy(frame.data, get_data(), length_); } else ERROR("can_message_t not correctly initialized to be sent"); return frame; }