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                 {
 260                          can_subscription = it->second;
 261                 }
 262                 else
 263                 {
 264                          can_subscription = std::make_shared<low_can_subscription_t>(low_can_subscription_t(event_filter));
 265                         if(can_subscription->create_rx_filter(sig) < 0)
 266                                 {return -1;}
 267                         if(add_to_event_loop(can_subscription) < 0)
 268                                 {return -1;}
 269                 }
 270
 271                 if(subscribe_unsubscribe_signal(request, subscribe, can_subscription, s) < 0)
 272                         {return -1;}
 273
 274                 rets++;
 275                 AFB_DEBUG("signal: %s subscribed", sig->get_name().c_str());
 276         }
 277         return rets;
 278 }
 279
 280 ///
 281 /// @brief subscribe to all signals in the vector signals
 282 ///
 283 /// @param[in] afb_req request : contains original request use to subscribe or unsubscribe
 284 /// @param[in] subscribe boolean value, which chooses between a subscription operation or an unsubscription
 285 /// @param[in] signals -  struct containing vectors with can_signal_t and diagnostic_messages to subscribe
 286 ///
 287 /// @return Number of correctly subscribed signal
 288 ///
 289 static int subscribe_unsubscribe_signals(afb_req_t request,
 290                                          bool subscribe,
 291                                          const struct utils::signals_found& signals,
 292                                          struct event_filter_t& event_filter)
 293 {
 294         int rets = 0;
 295         utils::signals_manager_t& sm = utils::signals_manager_t::instance();
 296
 297         std::lock_guard<std::mutex> subscribed_signals_lock(sm.get_subscribed_signals_mutex());
 298         std::map<int, std::shared_ptr<low_can_subscription_t> >& s = sm.get_subscribed_signals();
 299
 300         rets += subscribe_unsubscribe_diagnostic_messages(request, subscribe, signals.diagnostic_messages, event_filter, s, false);
 301         rets += subscribe_unsubscribe_can_signals(request, subscribe, signals.can_signals, event_filter, s);
 302
 303         return rets;
 304 }
 305
 306 static int one_subscribe_unsubscribe(afb_req_t request,
 307                                      bool subscribe,
 308                                      const std::string& tag,
 309                                      json_object* args)
 310 {
 311         int ret = 0;
 312         struct event_filter_t event_filter;
 313         struct json_object  *filter, *obj;
 314         struct utils::signals_found sf;
 315
 316         // computes the filter
 317         if (json_object_object_get_ex(args, "filter", &filter))
 318         {
 319                 if (json_object_object_get_ex(filter, "frequency", &obj)
 320                 && (json_object_is_type(obj, json_type_double) || json_object_is_type(obj, json_type_int)))
 321                         {event_filter.frequency = (float)json_object_get_double(obj);}
 322                 if (json_object_object_get_ex(filter, "min", &obj)
 323                 && (json_object_is_type(obj, json_type_double) || json_object_is_type(obj, json_type_int)))
 324                         {event_filter.min = (float)json_object_get_double(obj);}
 325                 if (json_object_object_get_ex(filter, "max", &obj)
 326                 && (json_object_is_type(obj, json_type_double) || json_object_is_type(obj, json_type_int)))
 327                         {event_filter.max = (float)json_object_get_double(obj);}
 328         }
 329
 330         // subscribe or unsubscribe
 331         openxc_DynamicField search_key = build_DynamicField(tag);
 332         sf = utils::signals_manager_t::instance().find_signals(search_key);
 333         if (sf.can_signals.empty() && sf.diagnostic_messages.empty())
 334         {
 335                 AFB_NOTICE("No signal(s) found for %s.", tag.c_str());
 336                 ret = -1;
 337         }
 338         else
 339                 {ret = subscribe_unsubscribe_signals(request, subscribe, sf, event_filter);}
 340
 341         return ret;
 342 }
 343 static int process_one_subscribe_args(afb_req_t request, bool subscribe, json_object *args)
 344 {
 345         int rc = 0, rc2=0;
 346         json_object *x = nullptr, *event = nullptr;
 347         if(args == NULL ||
 348                 !json_object_object_get_ex(args, "event", &event))
 349         {
 350                 rc = one_subscribe_unsubscribe(request, subscribe, "*", args);
 351         }
 352         else if (json_object_get_type(event) != json_type_array)
 353         {
 354                 rc = one_subscribe_unsubscribe(request, subscribe, json_object_get_string(event), args);
 355         }
 356         else
 357         {
 358                 for (int i = 0 ; i < json_object_array_length(event); i++)
 359                 {
 360                         x = json_object_array_get_idx(event, i);
 361                         rc2 = one_subscribe_unsubscribe(request, subscribe, json_object_get_string(x), args);
 362                         if (rc >= 0)
 363                                 rc = rc2 >= 0 ? rc + rc2 : rc2;
 364                 }
 365         }
 366         return rc;
 367 }
 368
 369 static void do_subscribe_unsubscribe(afb_req_t request, bool subscribe)
 370 {
 371         int rc = 0;
 372         struct json_object *args, *x;
 373
 374         args = afb_req_json(request);
 375         if (json_object_get_type(args) == json_type_array)
 376         {
 377                 for(int i = 0; i < json_object_array_length(args); i++)
 378                 {
 379                         x = json_object_array_get_idx(args, i);
 380                         rc += process_one_subscribe_args(request, subscribe, x);
 381                 }
 382         }
 383         else
 384         {
 385                 rc += process_one_subscribe_args(request, subscribe, args);
 386         }
 387
 388         if (rc >= 0)
 389                 afb_req_success(request, NULL, NULL);
 390         else
 391                 afb_req_fail(request, "error", NULL);
 392 }
 393
 394 void auth(afb_req_t request)
 395 {
 396         afb_req_session_set_LOA(request, 1);
 397         afb_req_success(request, NULL, NULL);
 398 }
 399
 400 void subscribe(afb_req_t request)
 401 {
 402         do_subscribe_unsubscribe(request, true);
 403 }
 404
 405 void unsubscribe(afb_req_t request)
 406 {
 407         do_subscribe_unsubscribe(request, false);
 408 }
 409
 410 static int send_frame(struct canfd_frame& cfd, const std::string& bus_name)
 411 {
 412         if(bus_name.empty()) {
 413                 return -1;
 414         }
 415
 416         std::map<std::string, std::shared_ptr<low_can_socket_t> >& cd = application_t::instance().get_can_devices();
 417
 418         if( cd.count(bus_name) == 0)
 419                 {cd[bus_name] = std::make_shared<low_can_socket_t>(low_can_socket_t());}
 420
 421         return cd[bus_name]->tx_send(cfd, bus_name);
 422 }
 423
 424 static void write_raw_frame(afb_req_t request, const std::string& bus_name, json_object *json_value)
 425 {
 426         struct canfd_frame cfd;
 427         struct json_object *can_data = nullptr;
 428
 429         ::memset(&cfd, 0, sizeof(cfd));
 430
 431         if(wrap_json_unpack(json_value, "{si, si, so !}",
 432                               "can_id", &cfd.can_id,
 433                               "can_dlc", &cfd.len,
 434                               "can_data", &can_data))
 435         {
 436                 afb_req_fail(request, "Invalid", "Frame object malformed");
 437                 return;
 438         }
 439
 440         if(cfd.len <= 8 && cfd.len > 0)
 441         {
 442                 for (int i = 0 ; i < cfd.len ; i++)
 443                 {
 444                         struct json_object *one_can_data = json_object_array_get_idx(can_data, i);
 445                         cfd.data[i] = (json_object_is_type(one_can_data, json_type_int)) ?
 446                                         (uint8_t)json_object_get_int(one_can_data) : 0;
 447                 }
 448         }
 449         else
 450         {
 451                 afb_req_fail(request, "Invalid", "Data array must hold 1 to 8 values.");
 452                 return;
 453         }
 454
 455         if(! send_frame(cfd, application_t::instance().get_can_bus_manager().get_can_device_name(bus_name)))
 456                 afb_req_success(request, nullptr, "Message correctly sent");
 457         else
 458                 afb_req_fail(request, "Error", "sending the message. See the log for more details.");
 459 }
 460
 461 static void write_signal(afb_req_t request, const std::string& name, json_object *json_value)
 462 {
 463         struct canfd_frame cfd;
 464         struct utils::signals_found sf;
 465         signal_encoder encoder = nullptr;
 466         bool send = true;
 467
 468         ::memset(&cfd, 0, sizeof(cfd));
 469
 470         openxc_DynamicField search_key = build_DynamicField(name);
 471         sf = utils::signals_manager_t::instance().find_signals(search_key);
 472         openxc_DynamicField dynafield_value = build_DynamicField(json_value);
 473
 474         if (sf.can_signals.empty())
 475         {
 476                 afb_req_fail_f(request, "No signal(s) found for %s. Message not sent.", name.c_str());
 477                 return;
 478         }
 479
 480         std::shared_ptr<can_signal_t>& sig = sf.can_signals[0];
 481         if(! sig->get_writable())
 482         {
 483                 afb_req_fail_f(request, "%s isn't writable. Message not sent.", sig->get_name().c_str());
 484                 return;
 485         }
 486
 487         uint64_t value = (encoder = sig->get_encoder()) ?
 488                         encoder(*sig, dynafield_value, &send) :
 489                         encoder_t::encode_DynamicField(*sig, dynafield_value, &send);
 490
 491         cfd = encoder_t::build_frame(sig, value);
 492         if(! send_frame(cfd, sig->get_message()->get_bus_device_name()) && send)
 493                 afb_req_success(request, nullptr, "Message correctly sent");
 494         else
 495                 afb_req_fail(request, "Error", "Sending the message. See the log for more details.");
 496 }
 497
 498 void write(afb_req_t request)
 499 {
 500         struct json_object* args = nullptr, *json_value = nullptr;
 501         const char *name = nullptr;
 502
 503         args = afb_req_json(request);
 504
 505         // Process about Raw CAN message on CAN bus directly
 506         if (args != NULL && ! wrap_json_unpack(args, "{ss, so !}",
 507                                                "bus_name", &name,
 508                                                "frame", &json_value))
 509                 write_raw_frame(request, name, json_value);
 510
 511         // Search signal then encode value.
 512         else if(args != NULL &&
 513                 ! wrap_json_unpack(args, "{ss, so !}",
 514                                    "signal_name", &name,
 515                                    "signal_value", &json_value))
 516                 write_signal(request, std::string(name), json_value);
 517         else
 518                 afb_req_fail(request, "Error", "Request argument malformed");
 519 }
 520
 521 static struct json_object *get_signals_value(const std::string& name)
 522 {
 523         struct utils::signals_found sf;
 524         struct json_object *ans = nullptr;
 525
 526         openxc_DynamicField search_key = build_DynamicField(name);
 527         sf = utils::signals_manager_t::instance().find_signals(search_key);
 528
 529         if (sf.can_signals.empty())
 530         {
 531                 AFB_WARNING("No signal(s) found for %s.", name.c_str());
 532                 return NULL;
 533         }
 534         ans = json_object_new_array();
 535         for(const auto& sig: sf.can_signals)
 536         {
 537                 struct json_object *jobj = json_object_new_object();
 538                 json_object_object_add(jobj, "event", json_object_new_string(sig->get_name().c_str()));
 539                 json_object_object_add(jobj, "value", json_object_new_double(sig->get_last_value()));
 540                 json_object_array_add(ans, jobj);
 541         }
 542
 543         return ans;
 544 }
 545 void get(afb_req_t request)
 546 {
 547         int rc = 0;
 548         struct json_object* args = nullptr,
 549                 *json_name = nullptr;
 550         json_object *ans = nullptr;
 551
 552         args = afb_req_json(request);
 553
 554         // Process about Raw CAN message on CAN bus directly
 555         if (args != nullptr &&
 556                 (json_object_object_get_ex(args, "event", &json_name) && json_object_is_type(json_name, json_type_string) ))
 557         {
 558                 ans = get_signals_value(json_object_get_string(json_name));
 559                 if (!ans)
 560                         rc = -1;
 561         }
 562         else
 563         {
 564                 AFB_ERROR("Request argument malformed. Please use the following syntax:");
 565                 rc = -1;
 566         }
 567
 568         if (rc >= 0)
 569                 afb_req_success(request, ans, NULL);
 570         else
 571                 afb_req_fail(request, "error", NULL);
 572 }
 573
 574
 575 static struct json_object *list_can_message(const std::string& name)
 576 {
 577         struct utils::signals_found sf;
 578         struct json_object *ans = nullptr;
 579
 580         openxc_DynamicField search_key = build_DynamicField(name);
 581         sf = utils::signals_manager_t::instance().find_signals(search_key);
 582
 583         if (sf.can_signals.empty() && sf.diagnostic_messages.empty())
 584         {
 585                 AFB_WARNING("No signal(s) found for %s.", name.c_str());
 586                 return NULL;
 587         }
 588         ans = json_object_new_array();
 589         for(const auto& sig: sf.can_signals)
 590         {
 591                 json_object_array_add(ans,
 592                         json_object_new_string(sig->get_name().c_str()));
 593         }
 594         for(const auto& sig: sf.diagnostic_messages)
 595         {
 596                 json_object_array_add(ans,
 597                         json_object_new_string(sig->get_name().c_str()));
 598         }
 599
 600         return ans;
 601 }
 602
 603 void list(afb_req_t request)
 604 {
 605         int rc = 0;
 606         json_object *ans = nullptr;
 607         struct json_object* args = nullptr,
 608                 *json_name = nullptr;
 609         args = afb_req_json(request);
 610         const char *name;
 611         if ((args != nullptr) &&
 612                 (json_object_object_get_ex(args, "event", &json_name) && json_object_is_type(json_name, json_type_string)))
 613         {
 614                 name = json_object_get_string(json_name);
 615         }
 616         else
 617         {
 618                 name = "*";
 619         }
 620
 621         ans = list_can_message(name);
 622         if (!ans)
 623                 rc = -1;
 624
 625         if (rc >= 0)
 626                 afb_req_success(request, ans, NULL);
 627         else
 628                 afb_req_fail(request, "error", NULL);
 629 }
 630
 631 /// @brief Initialize the binding.
 632 ///
 633 /// @param[in] service Structure which represent the Application Framework Binder.
 634 ///
 635 /// @return Exit code, zero if success.
 636 int init_binding(afb_api_t api)
 637 {
 638         uint32_t ret = 1;
 639         can_bus_t& can_bus_manager = application_t::instance().get_can_bus_manager();
 640
 641         can_bus_manager.set_can_devices();
 642         can_bus_manager.start_threads();
 643
 644         /// Initialize Diagnostic manager that will handle obd2 requests.
 645         /// We pass by default the first CAN bus device to its Initialization.
 646         /// TODO: be able to choose the CAN bus device that will be use as Diagnostic bus.
 647         if(application_t::instance().get_diagnostic_manager().initialize())
 648                 ret = 0;
 649
 650         // Add a recurring dignostic message request to get engine speed at all times.
 651         openxc_DynamicField search_key = build_DynamicField("diagnostic_messages.engine.speed");
 652         struct utils::signals_found sf = utils::signals_manager_t::instance().find_signals(search_key);
 653
 654         if(sf.can_signals.empty() && sf.diagnostic_messages.size() == 1)
 655         {
 656                 afb_req_t request = nullptr;
 657
 658                 struct event_filter_t event_filter;
 659                 event_filter.frequency = sf.diagnostic_messages.front()->get_frequency();
 660
 661                 utils::signals_manager_t& sm = utils::signals_manager_t::instance();
 662                 std::map<int, std::shared_ptr<low_can_subscription_t> >& s = sm.get_subscribed_signals();
 663
 664                 subscribe_unsubscribe_diagnostic_messages(request, true, sf.diagnostic_messages, event_filter, s, true);
 665         }
 666
 667         if(ret)
 668                 AFB_ERROR("There was something wrong with CAN device Initialization.");
 669
 670         return ret;
 671 }