/* * 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 "../low-can-binding.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::ERROR}, rtr_flag_{false}, flags_{0} {} 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) : maxdlen_{maxdlen}, id_{id}, length_{length}, format_{format}, rtr_flag_{rtr_flag}, flags_{flags}, data_{data} {} /// /// @brief Retrieve id_ member value. /// /// @return id_ class member /// uint32_t can_message_t::get_id() const { return 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 /// 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::ERROR; 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 length_ member value. /// /// @return length_ class member /// uint8_t can_message_t::get_length() const { return length_; } /// /// @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::ERROR) { 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::ERROR) format_ = new_format; else ERROR(binder_interface, "%s: Can set format, wrong format chosen", __FUNCTION__); } /// /// @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_canfd_frame(const struct canfd_frame& frame, size_t nbytes) { 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(binder_interface, "%s: Got an CAN FD frame", __FUNCTION__); maxdlen = CANFD_MAX_DLEN; break; case CAN_MTU: DEBUG(binder_interface, "%s: Got a legacy CAN frame", __FUNCTION__); maxdlen = CAN_MAX_DLEN; break; default: ERROR(binder_interface, "%s: unsupported CAN frame", __FUNCTION__); break; } if (frame.can_id & CAN_ERR_FLAG) format = can_message_format_t::ERROR; else if (frame.can_id & CAN_EFF_FLAG) format = can_message_format_t::EXTENDED; else format = can_message_format_t::STANDARD; switch(format) { case can_message_format_t::STANDARD: id = frame.can_id & CAN_SFF_MASK; break; case can_message_format_t::EXTENDED: id = frame.can_id & CAN_EFF_MASK; break; case can_message_format_t::ERROR: id = frame.can_id & (CAN_ERR_MASK|CAN_ERR_FLAG); break; default: ERROR(binder_interface, "%s: Can set id, not a compatible format or format not set prior to set id.", __FUNCTION__); break; } /* 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(binder_interface, "%s: Found id: %X, format: %X, length: %X, data %02X%02X%02X%02X%02X%02X%02X%02X", __FUNCTION__, 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); } /// /// @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. /// 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(binder_interface, "%s: can_message_t not correctly initialized to be sent", __FUNCTION__); return frame; }