CAN-binder/low-can-binding/can/can-message.cpp

   1 /*
   2  * Copyright (C) 2015, 2016 "IoT.bzh"
   3  * Author "Romain Forlot" <romain.forlot@iot.bzh>
   4  *
   5  * Licensed under the Apache License, Version 2.0 (the "License");
   6  * you may not use this file except in compliance with the License.
   7  * You may obtain a copy of the License at
   8  *
   9  *       http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing, software
  12  * distributed under the License is distributed on an "AS IS" BASIS,
  13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  * See the License for the specific language governing permissions and
  15  * limitations under the License.
  16  */
  17
  18 #include "can-message.hpp"
  19
  20 #include <cstring>
  21
  22 #include "../binding/low-can-hat.hpp"
  23
  24 ///
  25 /// @brief Class constructor
  26 ///
  27 /// Constructor about can_message_t class.
  28 ///
  29 can_message_t::can_message_t()
  30         : maxdlen_{0}, id_{0}, length_{0}, format_{can_message_format_t::INVALID}, rtr_flag_{false}, flags_{0}, timestamp_{0}
  31 {}
  32
  33 can_message_t::can_message_t(uint8_t maxdlen,
  34         uint32_t id,
  35         uint8_t length,
  36         can_message_format_t format,
  37         bool rtr_flag,
  38         uint8_t flags,
  39         std::vector<uint8_t>& data,
  40         uint64_t timestamp)
  41         :  maxdlen_{maxdlen},
  42         id_{id},
  43         length_{length},
  44         format_{format},
  45         rtr_flag_{rtr_flag},
  46         flags_{flags},
  47         data_{data},
  48         timestamp_{timestamp}
  49 {}
  50
  51 ///
  52 /// @brief Retrieve id_ member value.
  53 ///
  54 /// @return id_ class member
  55 ///
  56 uint32_t can_message_t::get_id() const
  57 {
  58         return id_;
  59 }
  60
  61 ///
  62 /// @brief Retrieve RTR flag member.
  63 ///
  64 /// @return rtr_flags_ class member
  65 ///
  66 bool can_message_t::get_rtr_flag_() const
  67 {
  68         return rtr_flag_;
  69 }
  70
  71 ///
  72 /// @brief Retrieve format_ member value.
  73 ///
  74 /// @return format_ class member
  75 ///
  76 can_message_format_t can_message_t::get_format() const
  77 {
  78         if (format_ != can_message_format_t::STANDARD || format_ != can_message_format_t::EXTENDED)
  79                 return can_message_format_t::INVALID;
  80         return format_;
  81 }
  82
  83 ///
  84 /// @brief Retrieve flags_ member value.
  85 ///
  86 /// @return flags_ class member
  87 ///
  88 uint8_t can_message_t::get_flags() const
  89 {
  90         return flags_;
  91 }
  92
  93 ///
  94 /// @brief Retrieve data_ member value.
  95 ///
  96 /// @return pointer to the first element
  97 ///  of class member data_
  98 ///
  99 const uint8_t* can_message_t::get_data() const
 100 {
 101         return data_.data();
 102 }
 103
 104 ///
 105 /// @brief Retrieve data_ member whole vector
 106 ///
 107 /// @return the vector as is
 108 ///
 109 const std::vector<uint8_t> can_message_t::get_data_vector() const
 110 {
 111         return data_;
 112 }
 113
 114 ///
 115 /// @brief Retrieve length_ member value.
 116 ///
 117 /// @return length_ class member
 118 ///
 119 uint8_t can_message_t::get_length() const
 120 {
 121         return length_;
 122 }
 123
 124 uint64_t can_message_t::get_timestamp() const
 125 {
 126         return timestamp_;
 127 }
 128
 129 void can_message_t::set_timestamp(uint64_t timestamp)
 130 {
 131         timestamp_ = timestamp;
 132 }
 133
 134 ///
 135 /// @brief Control whether the object is correctly initialized
 136 ///  to be sent over the CAN bus
 137 ///
 138 /// @return true if object correctly initialized and false if not.
 139 ///
 140 bool can_message_t::is_correct_to_send()
 141 {
 142         if (id_ != 0 && length_ != 0 && format_ != can_message_format_t::INVALID)
 143         {
 144                 int i;
 145                 for(i=0;i<CAN_MESSAGE_SIZE;i++)
 146                         if(data_[i] != 0)
 147                                 return true;
 148         }
 149         return false;
 150 }
 151
 152 ///
 153 /// @brief Set format_ member value.
 154 ///
 155 /// Preferred way to initialize these members by using
 156 /// convert_from_canfd_frame method.
 157 ///
 158 /// @param[in] new_format - class member
 159 ///
 160 void can_message_t::set_format(const can_message_format_t new_format)
 161 {
 162         if(new_format == can_message_format_t::STANDARD || new_format == can_message_format_t::EXTENDED || new_format == can_message_format_t::INVALID)
 163                 format_ = new_format;
 164         else
 165                 ERROR(binder_interface, "%s: Can set format, wrong format chosen", __FUNCTION__);
 166 }
 167
 168 /// @brief Take a canfd_frame struct to initialize class members
 169 ///
 170 /// This is the preferred way to initialize class members.
 171 ///
 172 /// @param[in] frame - canfd_frame to convert coming from a read of CAN socket
 173 /// @param[in] nbytes - bytes read from socket read operation.
 174 ///
 175 /// @return A can_message_t object fully initialized with canfd_frame values.
 176 ///
 177 can_message_t can_message_t::convert_from_frame(const struct canfd_frame& frame, size_t nbytes, uint64_t timestamp)
 178 {
 179         uint8_t maxdlen, length, flags = (uint8_t)NULL;
 180         uint32_t id;
 181         can_message_format_t format;
 182         bool rtr_flag;
 183         std::vector<uint8_t> data;
 184
 185         switch(nbytes)
 186         {
 187                 case CANFD_MTU:
 188                         DEBUG(binder_interface, "%s: Got an CAN FD frame", __FUNCTION__);
 189                         maxdlen = CANFD_MAX_DLEN;
 190                         break;
 191                 case CAN_MTU:
 192                         DEBUG(binder_interface, "%s: Got a legacy CAN frame", __FUNCTION__);
 193                         maxdlen = CAN_MAX_DLEN;
 194                         break;
 195                 default:
 196                         ERROR(binder_interface, "%s: unsupported CAN frame", __FUNCTION__);
 197                         break;
 198         }
 199
 200         if (frame.can_id & CAN_ERR_FLAG)
 201         {
 202                 format = can_message_format_t::INVALID;
 203                 id = frame.can_id & (CAN_ERR_MASK|CAN_ERR_FLAG);
 204         }
 205         else if (frame.can_id & CAN_EFF_FLAG)
 206         {
 207                 format = can_message_format_t::EXTENDED;
 208                 id = frame.can_id & CAN_EFF_MASK;
 209         }
 210         else
 211         {
 212                 format = can_message_format_t::STANDARD;
 213                 id = frame.can_id & CAN_SFF_MASK;
 214         }
 215
 216         /* Overwrite length_ if RTR flags is detected.
 217          * standard CAN frames may have RTR enabled. There are no ERR frames with RTR */
 218         if (frame.can_id & CAN_RTR_FLAG)
 219         {
 220                 rtr_flag = true;
 221                 if(frame.len && frame.len <= CAN_MAX_DLC)
 222                 {
 223                         if(rtr_flag)
 224                                 length = frame.len& 0xF;
 225                         else
 226                         {
 227                                 length = (frame.len > maxdlen) ? maxdlen : frame.len;
 228                         }
 229                 }
 230         }
 231         else
 232         {
 233                 length = (frame.len > maxdlen) ? maxdlen : frame.len;
 234
 235                 /* Flags field only present for CAN FD frames*/
 236                 if(maxdlen == CANFD_MAX_DLEN)
 237                                 flags = frame.flags & 0xF;
 238
 239                 if (data.capacity() < maxdlen)
 240                         data.reserve(maxdlen);
 241                                 int i;
 242
 243                         data.clear();
 244                         /* maxdlen_ is now set at CAN_MAX_DLEN or CANFD_MAX_DLEN, respectively 8 and 64 bytes*/
 245                         for(i=0;i<maxdlen;i++)
 246                         {
 247                                 data.push_back(frame.data[i]);
 248                         };
 249
 250                 DEBUG(binder_interface, "%s: Found id: %X, format: %X, length: %X, data %02X%02X%02X%02X%02X%02X%02X%02X", __FUNCTION__,
 251                                                                 id, (uint8_t)format, length, data[0], data[1], data[2], data[3], data[4], data[5], data[6], data[7]);
 252         }
 253
 254         return can_message_t(maxdlen, id, length, format, rtr_flag, flags, data, timestamp);
 255 }
 256
 257 can_message_t can_message_t::convert_from_frame(const struct can_frame& frame, size_t nbytes, uint64_t timestamp)
 258 {
 259         uint8_t maxdlen, length, flags = (uint8_t)NULL;
 260         uint32_t id;
 261         can_message_format_t format;
 262         bool rtr_flag;
 263         std::vector<uint8_t> data;
 264
 265         if(nbytes <= CAN_MTU)
 266         {
 267                         DEBUG(binder_interface, "%s: Got a legacy CAN frame", __FUNCTION__);
 268                         maxdlen = CAN_MAX_DLEN;
 269         }
 270         else
 271         {
 272                         ERROR(binder_interface, "%s: unsupported CAN frame", __FUNCTION__);
 273         }
 274
 275         if (frame.can_id & CAN_ERR_FLAG)
 276         {
 277                 format = can_message_format_t::INVALID;
 278                 id = frame.can_id & (CAN_ERR_MASK|CAN_ERR_FLAG);
 279         }
 280         else if (frame.can_id & CAN_EFF_FLAG)
 281         {
 282                 format = can_message_format_t::EXTENDED;
 283                 id = frame.can_id & CAN_EFF_MASK;
 284         }
 285         else
 286         {
 287                 format = can_message_format_t::STANDARD;
 288                 id = frame.can_id & CAN_SFF_MASK;
 289         }
 290
 291         /* Overwrite length_ if RTR flags is detected.
 292          * standard CAN frames may have RTR enabled. There are no ERR frames with RTR */
 293         if (frame.can_id & CAN_RTR_FLAG)
 294         {
 295                 rtr_flag = true;
 296                 if(frame.can_dlc && frame.can_dlc <= CAN_MAX_DLC)
 297                 {
 298                         if(rtr_flag)
 299                                 length = frame.can_dlc& 0xF;
 300                         else
 301                         {
 302                                 length = (frame.can_dlc > maxdlen) ? maxdlen : frame.can_dlc;
 303                         }
 304                 }
 305         }
 306         else
 307         {
 308                 length = (frame.can_dlc > maxdlen) ? maxdlen : frame.can_dlc;
 309
 310                 if (data.capacity() < maxdlen)
 311                         data.reserve(maxdlen);
 312                                 int i;
 313
 314                         data.clear();
 315                         /* maxdlen_ is now set at CAN_MAX_DLEN or CANFD_MAX_DLEN, respectively 8 and 64 bytes*/
 316                         for(i=0;i<maxdlen;i++)
 317                         {
 318                                 data.push_back(frame.data[i]);
 319                         };
 320
 321 //              DEBUG(binder_interface, "%s: Found id: %X, format: %X, length: %X, data %02X%02X%02X%02X%02X%02X%02X%02X", __FUNCTION__,
 322 //                                                              id, (uint8_t)format, length, data[0], data[1], data[2], data[3], data[4], data[5], data[6], data[7]);
 323         }
 324
 325         return can_message_t(maxdlen, id, length, format, rtr_flag, flags, data, timestamp);
 326 }
 327
 328 ///
 329 /// @brief Take all initialized class's members and build an
 330 /// canfd_frame struct that can be use to send a CAN message over
 331 /// the bus.
 332 ///
 333 /// @return canfd_frame struct built from class members.
 334 ///
 335 struct canfd_frame can_message_t::convert_to_canfd_frame()
 336 {
 337         canfd_frame frame;
 338
 339         if(is_correct_to_send())
 340         {
 341                 frame.can_id = get_id();
 342                 frame.len = get_length();
 343                 ::memcpy(frame.data, get_data(), length_);
 344         }
 345         else
 346                 ERROR(binder_interface, "%s: can_message_t not correctly initialized to be sent", __FUNCTION__);
 347
 348         return frame;
 349 }
 350
 351 struct can_frame can_message_t::convert_to_can_frame()
 352 {
 353         can_frame frame;
 354
 355         if(is_correct_to_send())
 356         {
 357                 frame.can_id = get_id();
 358                 frame.can_dlc = get_length();
 359                 ::memcpy(frame.data, get_data(), length_);
 360         }
 361         else
 362                 ERROR(binder_interface, "%s: can_message_t not correctly initialized to be sent", __FUNCTION__);
 363
 364         return frame;
 365 }