low-can-binding/can/can-bus.cpp

   1 /*
   2  * Copyright (C) 2015, 2018 "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 <net/if.h>
  19 #include <sys/socket.h>
  20 #include <json-c/json.h>
  21 #include <linux/can/raw.h>
  22 #include <map>
  23 #include <cerrno>
  24 #include <vector>
  25 #include <string>
  26 #include <algorithm>
  27
  28 #include "can-bus.hpp"
  29
  30 #include "signals.hpp"
  31 #include "can-decoder.hpp"
  32 #include "../binding/application.hpp"
  33 #include "../utils/signals.hpp"
  34 #include "../utils/openxc-utils.hpp"
  35
  36 /// @brief Class destructor
  37 ///
  38 /// @param[in] conf_file - Stop threads and unlock them to correctly finish them
  39 /// even without any activity on the CAN bus.
  40 can_bus_t::~can_bus_t()
  41 {
  42         stop_threads();
  43         new_can_message_cv_.notify_one();
  44 }
  45
  46 /// @brief Class constructor
  47 can_bus_t::can_bus_t()
  48 {}
  49
  50 /// @brief Fills the CAN device map member with value from device
  51 ///
  52 /// @param[in] mapping configuration section.
  53 void can_bus_t::set_can_devices(json_object *mapping)
  54 {
  55         if (! mapping)
  56         {
  57                 AFB_ERROR("Can't initialize CAN buses with this empty mapping.");
  58                 return;
  59         }
  60
  61         struct json_object_iterator it = json_object_iter_begin(mapping);
  62         struct json_object_iterator end = json_object_iter_end(mapping);
  63         while (! json_object_iter_equal(&it, &end)) {
  64                 can_devices_mapping_.push_back(std::make_pair(
  65                         json_object_iter_peek_name(&it),
  66                         json_object_get_string(json_object_iter_peek_value(&it))
  67                         ));
  68                 json_object_iter_next(&it);
  69         }
  70 }
  71
  72 /// @brief Fills the CAN device map member with given values
  73 ///
  74 /// @param[in] mapping configuration section.
  75 void can_bus_t::set_can_devices(const std::vector<std::pair<std::string, std::string> >& mapping)
  76 {
  77         can_devices_mapping_ = mapping;
  78 }
  79
  80 /// @brief Take a decoded message to determine if its value complies with the desired
  81 /// filters.
  82 ///
  83 /// @param[in] vehicle_message - The decoded message to be analyzed.
  84 /// @param[in] can_subscription - the subscription which will be notified depending
  85 ///  on its filtering values. Filtering values are stored in the event_filtermember.
  86 ///
  87 /// @return True if the value is compliant with event filter values, false if not...
  88 bool can_bus_t::apply_filter(const openxc_VehicleMessage& vehicle_message, std::shared_ptr<low_can_subscription_t> can_subscription)
  89 {
  90         bool send = false;
  91         if(is_valid(vehicle_message))
  92         {
  93                 float min = can_subscription->get_min();
  94                 float max = can_subscription->get_max();
  95                 double value = get_numerical_from_DynamicField(vehicle_message);
  96                 send = (value < min || value > max) ? false : true;
  97         }
  98         return send;
  99 }
 100
 101 /// @brief Will make the decoding operation on a classic CAN message. It will not
 102 /// handle CAN commands nor diagnostic messages that have their own method to get
 103 /// this happens.
 104 ///
 105 /// It will add to the vehicle_message queue the decoded message and tell the event push
 106 /// thread to process it.
 107 ///
 108 /// @param[in] can_message - a single CAN message from the CAN socket read, to be decode.
 109 ///
 110 /// @return How many signals has been decoded.
 111 void can_bus_t::process_signals(std::shared_ptr<message_t> message, map_subscription& s)
 112 {
 113         int subscription_id = message->get_sub_id();
 114         openxc_DynamicField decoded_message;
 115         openxc_VehicleMessage vehicle_message;
 116
 117         if( s.find(subscription_id) != s.end() && afb_event_is_valid(s[subscription_id]->get_event()))
 118         {
 119                 bool send = true;
 120                 // First we have to found which signal_t it is
 121                 std::shared_ptr<low_can_subscription_t> subscription = s[subscription_id];
 122                 openxc_SimpleMessage s_message;
 123
 124                 // messages
 125                 if(subscription->get_message_definition() != nullptr)
 126                 {
 127                         openxc_DynamicField dynamicField_tmp;
 128                         json_object *signal_json_tmp;
 129                         decoded_message = build_DynamicField_json(json_object_new_array());
 130                         for(std::shared_ptr<signal_t> sig : subscription->get_message_definition()->get_signals())
 131                         {
 132                                 signal_json_tmp = json_object_new_object();
 133                                 dynamicField_tmp = decoder_t::translate_signal(*sig, message, &send);
 134                                 json_object_object_add(signal_json_tmp,"name", json_object_new_string(sig->get_name().c_str()));
 135                                 jsonify_DynamicField(dynamicField_tmp,signal_json_tmp);
 136                                 if(sig != nullptr && sig->get_unit() != "")
 137                                         json_object_object_add(signal_json_tmp, "unit", json_object_new_string(sig->get_unit().c_str()));
 138                                 json_object_array_add(decoded_message.json_value,signal_json_tmp);
 139                         }
 140                 }
 141                 else // signal
 142                 {
 143                         decoded_message = decoder_t::translate_signal(*subscription->get_signal(), message, &send);
 144                 }
 145
 146                 s_message = build_SimpleMessage(subscription->get_name(), decoded_message);
 147                 vehicle_message = build_VehicleMessage(s_message, message->get_timestamp());
 148
 149                 if(send && apply_filter(vehicle_message, subscription))
 150                 {
 151                         std::lock_guard<std::mutex> decoded_can_message_lock(decoded_can_message_mutex_);
 152                         push_new_vehicle_message(subscription_id, vehicle_message);
 153                         AFB_DEBUG("%s CAN signals processed.", subscription->get_name().c_str());
 154                 }
 155         }
 156 }
 157
 158 /// @brief Will make the decoding operation on a diagnostic CAN message.Then it find the subscribed signal
 159 /// corresponding and will add the vehicle_message to the queue of event to pushed before notifying
 160 /// the event push thread to process it.
 161 ///
 162 /// @param[in] manager - the diagnostic manager object that handle diagnostic communication
 163 /// @param[in] can_message - a single CAN message from the CAN socket read, to be decode.
 164 ///
 165 /// @return How many signals has been decoded.
 166 void can_bus_t::process_diagnostic_signals(diagnostic_manager_t& manager, std::shared_ptr<message_t> message, map_subscription& s)
 167 {
 168         int subscription_id = message->get_sub_id();
 169
 170         openxc_VehicleMessage vehicle_message = manager.find_and_decode_adr(message);
 171         if (message->get_timestamp())
 172                 vehicle_message.timestamp = message->get_timestamp();
 173         if( (vehicle_message.has_simple_message && vehicle_message.simple_message.has_name) &&
 174                 s.find(subscription_id) != s.end() && afb_event_is_valid(s[subscription_id]->get_event()))
 175         {
 176                 if (apply_filter(vehicle_message, s[subscription_id]))
 177                 {
 178                         std::lock_guard<std::mutex> decoded_can_message_lock(decoded_can_message_mutex_);
 179                         push_new_vehicle_message(subscription_id, vehicle_message);
 180                         AFB_DEBUG("%s CAN signals processed.",  s[subscription_id]->get_name().c_str());
 181                 }
 182         }
 183 }
 184
 185 /// @brief thread to decoding raw CAN messages.
 186 ///
 187 ///  Depending on the nature of message, if arbitration ID matches ID for a diagnostic response
 188 ///  then decoding a diagnostic message else use classic CAN signals decoding functions.
 189 ///
 190 /// It will take from the can_message_q_ queue the next can message to process then it search
 191 ///  about signal subscribed if there is a valid afb_event for it. We only decode signal for which a
 192 ///  subscription has been made. Can message will be decoded using translate_signal that will pass it to the
 193 ///  corresponding decoding function if there is one assigned for that signal. If not, it will be the default
 194 ///  noopDecoder function that will operate on it.
 195 ///
 196 ///  TODO: make diagnostic messages parsing optionnal.
 197 void can_bus_t::can_decode_message()
 198 {
 199         utils::signals_manager_t& sm = utils::signals_manager_t::instance();
 200
 201         while(is_decoding_)
 202         {
 203                 std::unique_lock<std::mutex> can_message_lock(can_message_mutex_);
 204                 new_can_message_cv_.wait(can_message_lock);
 205                 while(!can_message_q_.empty())
 206                 {
 207                         std::shared_ptr<message_t>  message = next_can_message();
 208                         can_message_lock.unlock();
 209
 210                         {
 211                                 std::lock_guard<std::mutex> subscribed_signals_lock(sm.get_subscribed_signals_mutex());
 212                                 map_subscription& s = sm.get_subscribed_signals();
 213                                 if(application_t::instance().get_diagnostic_manager().is_diagnostic_response(message))
 214                                         process_diagnostic_signals(application_t::instance().get_diagnostic_manager(), message, s);
 215                                 else
 216                                         process_signals(message, s);
 217                         }
 218                         can_message_lock.lock();
 219                 }
 220                 new_decoded_can_message_.notify_one();
 221                 can_message_lock.unlock();
 222         }
 223 }
 224
 225 /// @brief thread to push events to suscribers. It will read subscribed_signals map to look
 226 /// which are events that has to be pushed.
 227 void can_bus_t::can_event_push()
 228 {
 229         json_object* jo;
 230         utils::signals_manager_t& sm = utils::signals_manager_t::instance();
 231
 232         while(is_pushing_)
 233         {
 234                 std::unique_lock<std::mutex> decoded_can_message_lock(decoded_can_message_mutex_);
 235                 new_decoded_can_message_.wait(decoded_can_message_lock);
 236                 while(!vehicle_message_q_.empty())
 237                 {
 238                         std::pair<int, openxc_VehicleMessage> v_message = next_vehicle_message();
 239                         decoded_can_message_lock.unlock();
 240                         {
 241                                 std::lock_guard<std::mutex> subscribed_signals_lock(sm.get_subscribed_signals_mutex());
 242                                 map_subscription& s = sm.get_subscribed_signals();
 243                                 if(s.find(v_message.first) != s.end() && afb_event_is_valid(s[v_message.first]->get_event()))
 244                                 {
 245                                         jo = json_object_new_object();
 246                                         jsonify_vehicle(v_message.second, s[v_message.first]->get_signal(), jo);
 247                                         if(afb_event_push(s[v_message.first]->get_event(), jo) == 0)
 248                                         {
 249                                                 if(v_message.second.has_diagnostic_response)
 250                                                         on_no_clients(s[v_message.first], v_message.second.diagnostic_response.pid, s);
 251                                                 else
 252                                                         on_no_clients(s[v_message.first], s);
 253                                         }
 254                                 }
 255                         }
 256                         decoded_can_message_lock.lock();
 257                 }
 258                 decoded_can_message_lock.unlock();
 259         }
 260 }
 261
 262 /// @brief Will initialize threads that will decode
 263 ///  and push subscribed events.
 264 void can_bus_t::start_threads()
 265 {
 266         is_decoding_ = true;
 267         th_decoding_ = std::thread(&can_bus_t::can_decode_message, this);
 268         th_decoding_.detach();
 269
 270         is_pushing_ = true;
 271         th_pushing_ = std::thread(&can_bus_t::can_event_push, this);
 272         th_pushing_.detach();
 273 }
 274
 275 /// @brief Will stop all threads holded by can_bus_t object
 276 ///  which are decoding and pushing then will wait that's
 277 /// they'll finish their job.
 278 void can_bus_t::stop_threads()
 279 {
 280         is_decoding_ = false;
 281         is_pushing_ = false;
 282 }
 283
 284 /// @brief return new_can_message_cv_ member
 285 ///
 286 /// @return  return new_can_message_cv_ member
 287 std::condition_variable& can_bus_t::get_new_can_message_cv()
 288 {
 289         return new_can_message_cv_;
 290 }
 291
 292 /// @brief return can_message_mutex_ member
 293 ///
 294 /// @return  return can_message_mutex_ member
 295 std::mutex& can_bus_t::get_can_message_mutex()
 296 {
 297         return can_message_mutex_;
 298 }
 299
 300 /// @brief Return first can_message_t on the queue
 301 ///
 302 /// @return a can_message_t
 303 std::shared_ptr<message_t> can_bus_t::next_can_message()
 304 {
 305         std::shared_ptr<message_t> msg;
 306
 307         if(!can_message_q_.empty())
 308         {
 309                 msg = can_message_q_.front();
 310                 can_message_q_.pop();
 311                 std::string debug = msg->get_debug_message();
 312                 AFB_DEBUG(debug.c_str());
 313                 return msg;
 314         }
 315
 316         return msg;
 317 }
 318
 319 /// @brief Push a message_t into the queue
 320 ///
 321 /// @param[in] msg - the const reference message_t object to push into the queue
 322 void can_bus_t::push_new_can_message(std::shared_ptr<message_t> msg)
 323 {
 324         can_message_q_.push(msg);
 325 }
 326
 327 /// @brief Return first openxc_VehicleMessage on the queue
 328 ///
 329 /// @return a openxc_VehicleMessage containing a decoded can message
 330 std::pair<int, openxc_VehicleMessage> can_bus_t::next_vehicle_message()
 331 {
 332         std::pair<int, openxc_VehicleMessage> v_msg;
 333
 334         if(! vehicle_message_q_.empty())
 335         {
 336                 v_msg = vehicle_message_q_.front();
 337                 vehicle_message_q_.pop();
 338                 AFB_DEBUG("next vehicle message poped");
 339                 return v_msg;
 340         }
 341
 342         return v_msg;
 343 }
 344
 345 /// @brief Push a openxc_VehicleMessage into the queue
 346 ///
 347 /// @param[in] v_msg - const reference openxc_VehicleMessage object to push into the queue
 348 void can_bus_t::push_new_vehicle_message(int subscription_id, const openxc_VehicleMessage& v_msg)
 349 {
 350         vehicle_message_q_.push(std::make_pair(subscription_id, v_msg));
 351 }
 352
 353 /// @brief Return the CAN device index from the map
 354 /// map are sorted so index depend upon alphabetical sorting.
 355 int can_bus_t::get_can_device_index(const std::string& bus_name) const
 356 {
 357         int i = 0;
 358         for(const auto& d: can_devices_mapping_)
 359         {
 360                 if(d.first == bus_name)
 361                         break;
 362                 i++;
 363         }
 364         return i;
 365 }
 366
 367 /// @brief Return CAN device name from a logical CAN device name gotten from
 368 /// the signals.json description file which comes from a CAN databases file in
 369 /// general.
 370 const std::string can_bus_t::get_can_device_name(const std::string& id_name) const
 371 {
 372         std::string ret = "";
 373         for(const auto& d: can_devices_mapping_)
 374         {
 375                 if(d.first == id_name)
 376                 {
 377                         ret = d.second;
 378                         break;
 379                 }
 380         }
 381         return ret;
 382 }