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Diffstat (limited to 'low-can-binding/can/can-message.cpp')
| -rw-r--r-- | low-can-binding/can/can-message.cpp | 264 |
1 files changed, 264 insertions, 0 deletions
diff --git a/low-can-binding/can/can-message.cpp b/low-can-binding/can/can-message.cpp new file mode 100644 index 0000000..f61de67 --- /dev/null +++ b/low-can-binding/can/can-message.cpp @@ -0,0 +1,264 @@ +/* + * 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, "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_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, "set_max_data_length: Got an CAN FD frame"); + maxdlen = CANFD_MAX_DLEN; + break; + case CAN_MTU: + DEBUG(binder_interface, "set_max_data_length: Got a legacy CAN frame"); + maxdlen = CAN_MAX_DLEN; + break; + default: + ERROR(binder_interface, "set_max_data_length: unsupported CAN frame"); + 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, "ERROR: Can set id, not a compatible format or format not set prior to set id."); + 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, "convert_from_canfd_frame: 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); +} + +/// +/// @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, "can_message_t not correctly initialized to be sent"); + + return frame; +} |