low-can-binding/binding/low-can-cb.cpp

   1 /*
   2  * Copyright (C) 2015, 2016 "IoT.bzh"
   3  * Author "Romain Forlot" <romain.forlot@iot.bzh>
   4  * Author "Loic Collignon" <loic.collignon@iot.bzh>
   5  *
   6  * Licensed under the Apache License, Version 2.0 (the "License");
   7  * you may not use this file except in compliance with the License.
   8  * You may obtain a copy of the License at
   9  *
  10  *       http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  * Unless required by applicable law or agreed to in writing, software
  13  * distributed under the License is distributed on an "AS IS" BASIS,
  14  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  15  * See the License for the specific language governing permissions and
  16  * limitations under the License.
  17  */
  18
  19 #include "low-can-hat.hpp"
  20 #include "low-can-apidef.h"
  21
  22 #include <map>
  23 #include <queue>
  24 #include <mutex>
  25 #include <vector>
  26 #include <thread>
  27 #include <wrap-json.h>
  28 #include <systemd/sd-event.h>
  29
  30 #include "openxc.pb.h"
  31 #include "application.hpp"
  32 #include "../can/can-encoder.hpp"
  33 #include "../can/can-bus.hpp"
  34 #include "../can/can-signals.hpp"
  35 #include "../can/can-message.hpp"
  36 #include "../utils/signals.hpp"
  37 #include "../diagnostic/diagnostic-message.hpp"
  38 #include "../utils/openxc-utils.hpp"
  39
  40 ///******************************************************************************
  41 ///
  42 ///             SystemD event loop Callbacks
  43 ///
  44 ///*******************************************************************************/
  45
  46 void on_no_clients(std::shared_ptr<low_can_subscription_t> can_subscription, uint32_t pid, std::map<int, std::shared_ptr<low_can_subscription_t> >& s)
  47 {
  48         bool is_permanent_recurring_request = false;
  49
  50         if( ! can_subscription->get_diagnostic_message().empty() && can_subscription->get_diagnostic_message(pid) != nullptr)
  51         {
  52                 DiagnosticRequest diag_req = can_subscription->get_diagnostic_message(pid)->build_diagnostic_request();
  53                 active_diagnostic_request_t* adr = application_t::instance().get_diagnostic_manager().find_recurring_request(diag_req);
  54                 if( adr != nullptr)
  55                 {
  56                         is_permanent_recurring_request = adr->get_permanent();
  57
  58                         if(! is_permanent_recurring_request)
  59                                 application_t::instance().get_diagnostic_manager().cleanup_request(adr, true);
  60                 }
  61         }
  62
  63         if(! is_permanent_recurring_request)
  64                 on_no_clients(can_subscription, s);
  65 }
  66
  67 void on_no_clients(std::shared_ptr<low_can_subscription_t> can_subscription, std::map<int, std::shared_ptr<low_can_subscription_t> >& s)
  68 {
  69         auto it = s.find(can_subscription->get_index());
  70         s.erase(it);
  71 }
  72
  73 static void push_n_notify(const can_message_t& cm)
  74 {
  75         can_bus_t& cbm = application_t::instance().get_can_bus_manager();
  76         {
  77                 std::lock_guard<std::mutex> can_message_lock(cbm.get_can_message_mutex());
  78                 cbm.push_new_can_message(cm);
  79         }
  80         cbm.get_new_can_message_cv().notify_one();
  81 }
  82
  83 int read_message(sd_event_source *event_source, int fd, uint32_t revents, void *userdata)
  84 {
  85         low_can_subscription_t* can_subscription = (low_can_subscription_t*)userdata;
  86         if ((revents & EPOLLIN) != 0)
  87         {
  88                 can_message_t cm;
  89                 utils::socketcan_bcm_t& s = can_subscription->get_socket();
  90                 s >> cm;
  91
  92                 // Sure we got a valid CAN message ?
  93                 if(! cm.get_id() == 0 && ! cm.get_length() == 0)
  94                         {push_n_notify(cm);}
  95         }
  96
  97         // check if error or hangup
  98         if ((revents & (EPOLLERR|EPOLLRDHUP|EPOLLHUP)) != 0)
  99         {
 100                 sd_event_source_unref(event_source);
 101                 can_subscription->get_socket().close();
 102         }
 103         return 0;
 104 }
 105
 106 ///******************************************************************************
 107 ///
 108 ///             Subscription and unsubscription
 109 ///
 110 ///*******************************************************************************/
 111
 112 static int make_subscription_unsubscription(afb_req_t request,
 113                                             std::shared_ptr<low_can_subscription_t>& can_subscription,
 114                                             std::map<int, std::shared_ptr<low_can_subscription_t> >& s,
 115                                             bool subscribe)
 116 {
 117         /* Make the subscription or unsubscription to the event (if request is not null) */
 118         if(request &&
 119            ((subscribe ? afb_req_subscribe : afb_req_unsubscribe)(request, s[can_subscription->get_index()]->get_event())) < 0)
 120         {
 121                 AFB_ERROR("Operation goes wrong for signal: %s", can_subscription->get_name().c_str());
 122                 return -1;
 123         }
 124         return 0;
 125 }
 126
 127 static int create_event_handle(std::shared_ptr<low_can_subscription_t>& can_subscription,
 128                                std::map<int, std::shared_ptr<low_can_subscription_t> >& s)
 129 {
 130         int sub_index = can_subscription->get_index();
 131         can_subscription->set_event(afb_daemon_make_event(can_subscription->get_name().c_str()));
 132         s[sub_index] = can_subscription;
 133         if (!afb_event_is_valid(s[sub_index]->get_event()))
 134         {
 135                 AFB_ERROR("Can't create an event for %s, something goes wrong.", can_subscription->get_name().c_str());
 136                 return -1;
 137         }
 138         return 0;
 139 }
 140
 141 /// @brief This will determine if an event handle needs to be created and checks if
 142 /// we got a valid afb_event to get subscribe or unsubscribe. After that launch the subscription or unsubscription
 143 /// against the application framework using that event handle.
 144 static int subscribe_unsubscribe_signal(afb_req_t request,
 145                                         bool subscribe,
 146                                         std::shared_ptr<low_can_subscription_t>& can_subscription,
 147                                         std::map<int, std::shared_ptr<low_can_subscription_t> >& s)
 148 {
 149         int ret = -1;
 150         int sub_index = can_subscription->get_index();
 151
 152         if (can_subscription && s.find(sub_index) != s.end())
 153         {
 154                 if (!afb_event_is_valid(s[sub_index]->get_event()) && !subscribe)
 155                 {
 156                         AFB_NOTICE("Event isn't valid, no need to unsubscribed.");
 157                         ret = -1;
 158                 }
 159                 ret = 0;
 160         }
 161         else
 162         {
 163                 /* Event doesn't exist , so let's create it */
 164                 s[sub_index] = can_subscription;
 165                 ret = create_event_handle(can_subscription, s);
 166         }
 167
 168         // Checks if the event handler is correctly created, if it is, it
 169         // performs the subscription or unsubscription operations.
 170         if (ret < 0)
 171                 return ret;
 172         return make_subscription_unsubscription(request, can_subscription, s, subscribe);
 173 }
 174
 175 static int add_to_event_loop(std::shared_ptr<low_can_subscription_t>& can_subscription)
 176 {
 177                 struct sd_event_source* event_source = nullptr;
 178                 return ( sd_event_add_io(afb_daemon_get_event_loop(),
 179                         &event_source,
 180                         can_subscription->get_socket().socket(),
 181                         EPOLLIN,
 182                         read_message,
 183                         can_subscription.get()));
 184 }
 185
 186 static int subscribe_unsubscribe_diagnostic_messages(afb_req_t request,
 187                                                      bool subscribe,
 188                                                      std::vector<std::shared_ptr<diagnostic_message_t> > diagnostic_messages,
 189                                                      struct event_filter_t& event_filter,
 190                                                      std::map<int, std::shared_ptr<low_can_subscription_t> >& s,
 191                                                      bool perm_rec_diag_req)
 192 {
 193         int rets = 0;
 194         application_t& app = application_t::instance();
 195         diagnostic_manager_t& diag_m = app.get_diagnostic_manager();
 196
 197         for(const auto& sig : diagnostic_messages)
 198         {
 199                 DiagnosticRequest* diag_req = new DiagnosticRequest(sig->build_diagnostic_request());
 200                 event_filter.frequency = event_filter.frequency == 0 ? sig->get_frequency() : event_filter.frequency;
 201                 std::shared_ptr<low_can_subscription_t> can_subscription;
 202
 203                 auto it =  std::find_if(s.begin(), s.end(), [&sig](std::pair<int, std::shared_ptr<low_can_subscription_t> > sub){ return (! sub.second->get_diagnostic_message().empty());});
 204                 can_subscription = it != s.end() ?
 205                         it->second :
 206                         std::make_shared<low_can_subscription_t>(low_can_subscription_t(event_filter));
 207                 // If the requested diagnostic message is not supported by the car then unsubcribe it
 208                 // no matter what we want, worst case will be a failed unsubscription but at least we won't
 209                 // poll a PID for nothing.
 210                 if(sig->get_supported() && subscribe)
 211                 {
 212                         if (!app.isEngineOn())
 213                                 AFB_WARNING("signal: Engine is off, %s won't received responses until it's on",  sig->get_name().c_str());
 214
 215                         diag_m.add_recurring_request(diag_req, sig->get_name().c_str(), false, sig->get_decoder(), sig->get_callback(), event_filter.frequency, perm_rec_diag_req);
 216                         if(can_subscription->create_rx_filter(sig) < 0)
 217                                 {return -1;}
 218                         AFB_DEBUG("Signal: %s subscribed", sig->get_name().c_str());
 219                         if(it == s.end() && add_to_event_loop(can_subscription) < 0)
 220                         {
 221                                 diag_m.cleanup_request(
 222                                         diag_m.find_recurring_request(*diag_req), true);
 223                                 AFB_WARNING("signal: %s isn't supported. Canceling operation.",  sig->get_name().c_str());
 224                                 return -1;
 225                         }
 226                 }
 227                 else
 228                 {
 229                         if(sig->get_supported())
 230                         {AFB_DEBUG("%s cancelled due to unsubscribe", sig->get_name().c_str());}
 231                         else
 232                         {
 233                                 AFB_WARNING("signal: %s isn't supported. Canceling operation.", sig->get_name().c_str());
 234                                 return -1;
 235                         }
 236                 }
 237                 int ret = subscribe_unsubscribe_signal(request, subscribe, can_subscription, s);
 238                 if(ret < 0)
 239                         return ret;
 240
 241                 rets++;
 242         }
 243
 244         return rets;
 245 }
 246
 247 static int subscribe_unsubscribe_can_signals(afb_req_t request,
 248                                              bool subscribe,
 249                                              std::vector<std::shared_ptr<can_signal_t> > can_signals,
 250                                              struct event_filter_t& event_filter,
 251                                              std::map<int, std::shared_ptr<low_can_subscription_t> >& s)
 252 {
 253         int rets = 0;
 254         for(const auto& sig: can_signals)
 255         {
 256                 auto it =  std::find_if(s.begin(), s.end(), [&sig, &event_filter](std::pair<int, std::shared_ptr<low_can_subscription_t> > sub){ return sub.second->is_signal_subscription_corresponding(sig, event_filter) ; });
 257                 std::shared_ptr<low_can_subscription_t> can_subscription;
 258                 if(it != s.end())
 259                         {can_subscription = it->second;}
 260                 else
 261                 {
 262                          can_subscription = std::make_shared<low_can_subscription_t>(low_can_subscription_t(event_filter));
 263                         if(can_subscription->create_rx_filter(sig) < 0)
 264                                 {return -1;}
 265                         if(add_to_event_loop(can_subscription) < 0)
 266                                 {return -1;}
 267                 }
 268
 269                 if(subscribe_unsubscribe_signal(request, subscribe, can_subscription, s) < 0)
 270                         {return -1;}
 271
 272                 rets++;
 273                 AFB_DEBUG("signal: %s subscribed", sig->get_name().c_str());
 274         }
 275         return rets;
 276 }
 277
 278 ///
 279 /// @brief subscribe to all signals in the vector signals
 280 ///
 281 /// @param[in] afb_req request : contains original request use to subscribe or unsubscribe
 282 /// @param[in] subscribe boolean value, which chooses between a subscription operation or an unsubscription
 283 /// @param[in] signals -  struct containing vectors with can_signal_t and diagnostic_messages to subscribe
 284 ///
 285 /// @return Number of correctly subscribed signal
 286 ///
 287 static int subscribe_unsubscribe_signals(afb_req_t request,
 288                                          bool subscribe,
 289                                          const struct utils::signals_found& signals,
 290                                          struct event_filter_t& event_filter)
 291 {
 292         int rets = 0;
 293         utils::signals_manager_t& sm = utils::signals_manager_t::instance();
 294
 295         std::lock_guard<std::mutex> subscribed_signals_lock(sm.get_subscribed_signals_mutex());
 296         std::map<int, std::shared_ptr<low_can_subscription_t> >& s = sm.get_subscribed_signals();
 297
 298         rets += subscribe_unsubscribe_diagnostic_messages(request, subscribe, signals.diagnostic_messages, event_filter, s, false);
 299         rets += subscribe_unsubscribe_can_signals(request, subscribe, signals.can_signals, event_filter, s);
 300
 301         return rets;
 302 }
 303
 304 static int one_subscribe_unsubscribe(afb_req_t request,
 305                                      bool subscribe,
 306                                      const std::string& tag,
 307                                      json_object* args)
 308 {
 309         int ret = 0;
 310         struct event_filter_t event_filter;
 311         struct json_object  *filter, *obj;
 312         struct utils::signals_found sf;
 313
 314         // computes the filter
 315         if (json_object_object_get_ex(args, "filter", &filter))
 316         {
 317                 if (json_object_object_get_ex(filter, "frequency", &obj)
 318                 && (json_object_is_type(obj, json_type_double) || json_object_is_type(obj, json_type_int)))
 319                         {event_filter.frequency = (float)json_object_get_double(obj);}
 320                 if (json_object_object_get_ex(filter, "min", &obj)
 321                 && (json_object_is_type(obj, json_type_double) || json_object_is_type(obj, json_type_int)))
 322                         {event_filter.min = (float)json_object_get_double(obj);}
 323                 if (json_object_object_get_ex(filter, "max", &obj)
 324                 && (json_object_is_type(obj, json_type_double) || json_object_is_type(obj, json_type_int)))
 325                         {event_filter.max = (float)json_object_get_double(obj);}
 326         }
 327
 328         // subscribe or unsubscribe
 329         openxc_DynamicField search_key = build_DynamicField(tag);
 330         sf = utils::signals_manager_t::instance().find_signals(search_key);
 331         if (sf.can_signals.empty() && sf.diagnostic_messages.empty())
 332         {
 333                 AFB_NOTICE("No signal(s) found for %s.", tag.c_str());
 334                 ret = -1;
 335         }
 336         else
 337                 {ret = subscribe_unsubscribe_signals(request, subscribe, sf, event_filter);}
 338
 339         return ret;
 340 }
 341 static int process_one_subscribe_args(afb_req_t request, bool subscribe, json_object *args)
 342 {
 343         int rc = 0, rc2=0;
 344         json_object *x = nullptr, *event = nullptr;
 345         if(args == NULL ||
 346                 !json_object_object_get_ex(args, "event", &event))
 347         {
 348                 rc = one_subscribe_unsubscribe(request, subscribe, "*", args);
 349         }
 350         else if (json_object_get_type(event) != json_type_array)
 351         {
 352                 rc = one_subscribe_unsubscribe(request, subscribe, json_object_get_string(event), args);
 353         }
 354         else
 355         {
 356                 for (int i = 0 ; i < json_object_array_length(event); i++)
 357                 {
 358                         x = json_object_array_get_idx(event, i);
 359                         rc2 = one_subscribe_unsubscribe(request, subscribe, json_object_get_string(x), args);
 360                         if (rc >= 0)
 361                                 rc = rc2 >= 0 ? rc + rc2 : rc2;
 362                 }
 363         }
 364         return rc;
 365 }
 366
 367 static void do_subscribe_unsubscribe(afb_req_t request, bool subscribe)
 368 {
 369         int rc = 0;
 370         struct json_object *args, *x;
 371
 372         args = afb_req_json(request);
 373         if (json_object_get_type(args) == json_type_array)
 374         {
 375                 for(int i = 0; i < json_object_array_length(args); i++)
 376                 {
 377                         x = json_object_array_get_idx(args, i);
 378                         rc += process_one_subscribe_args(request, subscribe, x);
 379                 }
 380         }
 381         else
 382         {
 383                 rc += process_one_subscribe_args(request, subscribe, args);
 384         }
 385
 386         if (rc >= 0)
 387                 afb_req_success(request, NULL, NULL);
 388         else
 389                 afb_req_fail(request, "error", NULL);
 390 }
 391
 392 void auth(afb_req_t request)
 393 {
 394         afb_req_session_set_LOA(request, 1);
 395         afb_req_success(request, NULL, NULL);
 396 }
 397
 398 void subscribe(afb_req_t request)
 399 {
 400         do_subscribe_unsubscribe(request, true);
 401 }
 402
 403 void unsubscribe(afb_req_t request)
 404 {
 405         do_subscribe_unsubscribe(request, false);
 406 }
 407
 408 static int send_frame(struct canfd_frame& cfd, const std::string& bus_name)
 409 {
 410         if(bus_name.empty()) {
 411                 return -1;
 412         }
 413
 414         std::map<std::string, std::shared_ptr<low_can_socket_t> >& cd = application_t::instance().get_can_devices();
 415
 416         if( cd.count(bus_name) == 0)
 417                 {cd[bus_name] = std::make_shared<low_can_socket_t>(low_can_socket_t());}
 418
 419         return cd[bus_name]->tx_send(cfd, bus_name);
 420 }
 421
 422 static void write_raw_frame(afb_req_t request, const std::string& bus_name, json_object *json_value)
 423 {
 424         struct canfd_frame cfd;
 425         struct json_object *can_data = nullptr;
 426
 427         ::memset(&cfd, 0, sizeof(cfd));
 428
 429         if(wrap_json_unpack(json_value, "{si, si, so !}",
 430                               "can_id", &cfd.can_id,
 431                               "can_dlc", &cfd.len,
 432                               "can_data", &can_data))
 433         {
 434                 afb_req_fail(request, "Invalid", "Frame object malformed");
 435                 return;
 436         }
 437
 438         if(cfd.len <= 8 && cfd.len > 0)
 439         {
 440                 for (int i = 0 ; i < cfd.len ; i++)
 441                 {
 442                         struct json_object *one_can_data = json_object_array_get_idx(can_data, i);
 443                         cfd.data[i] = (json_object_is_type(one_can_data, json_type_int)) ?
 444                                         (uint8_t)json_object_get_int(one_can_data) : 0;
 445                 }
 446         }
 447         else
 448         {
 449                 afb_req_fail(request, "Invalid", "Data array must hold 1 to 8 values.");
 450                 return;
 451         }
 452
 453         if(! send_frame(cfd, application_t::instance().get_can_bus_manager().get_can_device_name(bus_name)))
 454                 afb_req_success(request, nullptr, "Message correctly sent");
 455         else
 456                 afb_req_fail(request, "Error", "sending the message. See the log for more details.");
 457 }
 458
 459 static void write_signal(afb_req_t request, const std::string& name, json_object *json_value)
 460 {
 461         struct canfd_frame cfd;
 462         struct utils::signals_found sf;
 463         signal_encoder encoder = nullptr;
 464         bool send = true;
 465
 466         ::memset(&cfd, 0, sizeof(cfd));
 467
 468         openxc_DynamicField search_key = build_DynamicField(name);
 469         sf = utils::signals_manager_t::instance().find_signals(search_key);
 470         openxc_DynamicField dynafield_value = build_DynamicField(json_value);
 471
 472         if (sf.can_signals.empty())
 473         {
 474                 afb_req_fail_f(request, "No signal(s) found for %s. Message not sent.", name.c_str());
 475                 return;
 476         }
 477
 478         std::shared_ptr<can_signal_t>& sig = sf.can_signals[0];
 479         if(! sig->get_writable())
 480         {
 481                 afb_req_fail_f(request, "%s isn't writable. Message not sent.", sig->get_name().c_str());
 482                 return;
 483         }
 484
 485         uint64_t value = (encoder = sig->get_encoder()) ?
 486                         encoder(*sig, dynafield_value, &send) :
 487                         encoder_t::encode_DynamicField(*sig, dynafield_value, &send);
 488
 489         cfd = encoder_t::build_frame(sig, value);
 490         if(! send_frame(cfd, sig->get_message()->get_bus_device_name()) && send)
 491                 afb_req_success(request, nullptr, "Message correctly sent");
 492         else
 493                 afb_req_fail(request, "Error", "Sending the message. See the log for more details.");
 494 }
 495
 496 void write(afb_req_t request)
 497 {
 498         struct json_object* args = nullptr, *json_value = nullptr;
 499         const char *name = nullptr;
 500
 501         args = afb_req_json(request);
 502
 503         // Process about Raw CAN message on CAN bus directly
 504         if (args != NULL && ! wrap_json_unpack(args, "{ss, so !}",
 505                                                "bus_name", &name,
 506                                                "frame", &json_value))
 507                 write_raw_frame(request, name, json_value);
 508
 509         // Search signal then encode value.
 510         else if(args != NULL &&
 511                 ! wrap_json_unpack(args, "{ss, so !}",
 512                                    "signal_name", &name,
 513                                    "signal_value", &json_value))
 514                 write_signal(request, std::string(name), json_value);
 515         else
 516                 afb_req_fail(request, "Error", "Request argument malformed");
 517 }
 518
 519 static struct json_object *get_signals_value(const std::string& name)
 520 {
 521         struct utils::signals_found sf;
 522         struct json_object *ans = nullptr;
 523
 524         openxc_DynamicField search_key = build_DynamicField(name);
 525         sf = utils::signals_manager_t::instance().find_signals(search_key);
 526
 527         if (sf.can_signals.empty())
 528         {
 529                 AFB_WARNING("No signal(s) found for %s.", name.c_str());
 530                 return NULL;
 531         }
 532         ans = json_object_new_array();
 533         for(const auto& sig: sf.can_signals)
 534         {
 535                 struct json_object *jobj = json_object_new_object();
 536                 json_object_object_add(jobj, "event", json_object_new_string(sig->get_name().c_str()));
 537                 json_object_object_add(jobj, "value", json_object_new_double(sig->get_last_value()));
 538                 json_object_array_add(ans, jobj);
 539         }
 540
 541         return ans;
 542 }
 543 void get(afb_req_t request)
 544 {
 545         int rc = 0;
 546         struct json_object* args = nullptr,
 547                 *json_name = nullptr;
 548         json_object *ans = nullptr;
 549
 550         args = afb_req_json(request);
 551
 552         // Process about Raw CAN message on CAN bus directly
 553         if (args != nullptr &&
 554                 (json_object_object_get_ex(args, "event", &json_name) && json_object_is_type(json_name, json_type_string) ))
 555         {
 556                 ans = get_signals_value(json_object_get_string(json_name));
 557                 if (!ans)
 558                         rc = -1;
 559         }
 560         else
 561         {
 562                 AFB_ERROR("Request argument malformed. Please use the following syntax:");
 563                 rc = -1;
 564         }
 565
 566         if (rc >= 0)
 567                 afb_req_success(request, ans, NULL);
 568         else
 569                 afb_req_fail(request, "error", NULL);
 570 }
 571
 572
 573 static struct json_object *list_can_message(const std::string& name)
 574 {
 575         struct utils::signals_found sf;
 576         struct json_object *ans = nullptr;
 577
 578         openxc_DynamicField search_key = build_DynamicField(name);
 579         sf = utils::signals_manager_t::instance().find_signals(search_key);
 580
 581         if (sf.can_signals.empty() && sf.diagnostic_messages.empty())
 582         {
 583                 AFB_WARNING("No signal(s) found for %s.", name.c_str());
 584                 return NULL;
 585         }
 586         ans = json_object_new_array();
 587         for(const auto& sig: sf.can_signals)
 588         {
 589                 json_object_array_add(ans,
 590                         json_object_new_string(sig->get_name().c_str()));
 591         }
 592         for(const auto& sig: sf.diagnostic_messages)
 593         {
 594                 json_object_array_add(ans,
 595                         json_object_new_string(sig->get_name().c_str()));
 596         }
 597
 598         return ans;
 599 }
 600
 601 void list(afb_req_t request)
 602 {
 603         int rc = 0;
 604         json_object *ans = nullptr;
 605         struct json_object* args = nullptr,
 606                 *json_name = nullptr;
 607         args = afb_req_json(request);
 608         const char *name;
 609         if ((args != nullptr) &&
 610                 (json_object_object_get_ex(args, "event", &json_name) && json_object_is_type(json_name, json_type_string)))
 611         {
 612                 name = json_object_get_string(json_name);
 613         }
 614         else
 615         {
 616                 name = "*";
 617         }
 618
 619         ans = list_can_message(name);
 620         if (!ans)
 621                 rc = -1;
 622
 623         if (rc >= 0)
 624                 afb_req_success(request, ans, NULL);
 625         else
 626                 afb_req_fail(request, "error", NULL);
 627 }
 628
 629 /// @brief Initialize the binding.
 630 ///
 631 /// @param[in] service Structure which represent the Application Framework Binder.
 632 ///
 633 /// @return Exit code, zero if success.
 634 int init_binding(afb_api_t api)
 635 {
 636         uint32_t ret = 1;
 637         can_bus_t& can_bus_manager = application_t::instance().get_can_bus_manager();
 638
 639         can_bus_manager.set_can_devices();
 640         can_bus_manager.start_threads();
 641
 642         /// Initialize Diagnostic manager that will handle obd2 requests.
 643         /// We pass by default the first CAN bus device to its Initialization.
 644         /// TODO: be able to choose the CAN bus device that will be use as Diagnostic bus.
 645         if(application_t::instance().get_diagnostic_manager().initialize())
 646                 ret = 0;
 647
 648         // Add a recurring dignostic message request to get engine speed at all times.
 649         openxc_DynamicField search_key = build_DynamicField("diagnostic_messages.engine.speed");
 650         struct utils::signals_found sf = utils::signals_manager_t::instance().find_signals(search_key);
 651
 652         if(sf.can_signals.empty() && sf.diagnostic_messages.size() == 1)
 653         {
 654                 afb_req_t request = nullptr;
 655
 656                 struct event_filter_t event_filter;
 657                 event_filter.frequency = sf.diagnostic_messages.front()->get_frequency();
 658
 659                 utils::signals_manager_t& sm = utils::signals_manager_t::instance();
 660                 std::map<int, std::shared_ptr<low_can_subscription_t> >& s = sm.get_subscribed_signals();
 661
 662                 subscribe_unsubscribe_diagnostic_messages(request, true, sf.diagnostic_messages, event_filter, s, true);
 663         }
 664
 665         if(ret)
 666                 AFB_ERROR("There was something wrong with CAN device Initialization.");
 667
 668         return ret;
 669 }