CAN-binder/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
  21 #include <map>
  22 #include <queue>
  23 #include <mutex>
  24 #include <vector>
  25 #include <thread>
  26 #include <json-c/json.h>
  27 #include <systemd/sd-event.h>
  28
  29 #include "openxc.pb.h"
  30 #include "application.hpp"
  31 #include "../can/can-bus.hpp"
  32 #include "../can/can-signals.hpp"
  33 #include "../can/can-message.hpp"
  34 #include "../utils/signals.hpp"
  35 #include "../diagnostic/diagnostic-message.hpp"
  36 #include "../utils/openxc-utils.hpp"
  37
  38 extern "C"
  39 {
  40         #include <afb/afb-service-itf.h>
  41 };
  42
  43
  44 ///******************************************************************************
  45 ///
  46 ///             SystemD event loop Callbacks
  47 ///
  48 ///*******************************************************************************/
  49
  50 void on_no_clients(std::shared_ptr<low_can_subscription_t> can_subscription, uint32_t pid)
  51 {
  52         if( ! can_subscription->get_diagnostic_message().empty() && can_subscription->get_diagnostic_message(pid) != nullptr)
  53         {
  54                 DiagnosticRequest diag_req = can_subscription->get_diagnostic_message(pid)->build_diagnostic_request();
  55                 active_diagnostic_request_t* adr = application_t::instance().get_diagnostic_manager().find_recurring_request(diag_req);
  56                 if( adr != nullptr)
  57                         application_t::instance().get_diagnostic_manager().cleanup_request(adr, true);
  58         }
  59
  60         on_no_clients(can_subscription);
  61 }
  62
  63 void on_no_clients(std::shared_ptr<low_can_subscription_t> can_subscription)
  64 {
  65         utils::signals_manager_t& sm = utils::signals_manager_t::instance();
  66         std::lock_guard<std::mutex> subscribed_signals_lock(sm.get_subscribed_signals_mutex());
  67         std::map<int, std::shared_ptr<low_can_subscription_t> >& s = sm.get_subscribed_signals();
  68         auto it = s.find(can_subscription->get_index());
  69         s.erase(it);
  70 }
  71
  72 static void push_n_notify(const can_message_t& cm)
  73 {
  74         can_bus_t& cbm = application_t::instance().get_can_bus_manager();
  75         {
  76                 std::lock_guard<std::mutex> can_message_lock(cbm.get_can_message_mutex());
  77                 cbm.push_new_can_message(cm);
  78         }
  79         cbm.get_new_can_message_cv().notify_one();
  80 }
  81
  82 int read_message(sd_event_source *event_source, int fd, uint32_t revents, void *userdata)
  83 {
  84         low_can_subscription_t* can_subscription = (low_can_subscription_t*)userdata;
  85         if ((revents & EPOLLIN) != 0)
  86         {
  87                 can_message_t cm;
  88                 utils::socketcan_bcm_t& s = can_subscription->get_socket();
  89                 s >> cm;
  90
  91                 push_n_notify(cm);
  92         }
  93
  94         /* check if error or hangup */
  95         if ((revents & (EPOLLERR|EPOLLRDHUP|EPOLLHUP)) != 0)
  96         {
  97                 sd_event_source_unref(event_source);
  98                 can_subscription->get_socket().close();
  99         }
 100         return 0;
 101 }
 102
 103 ///******************************************************************************
 104 ///
 105 ///             Subscription and unsubscription
 106 ///
 107 ///*******************************************************************************/
 108
 109 static int make_subscription_unsubscription(struct afb_req request, std::shared_ptr<low_can_subscription_t>& can_subscription, std::map<int, std::shared_ptr<low_can_subscription_t> >& s, bool subscribe)
 110 {
 111         /* Make the subscription or unsubscription to the event */
 112         if (((subscribe ? afb_req_subscribe : afb_req_unsubscribe)(request, s[can_subscription->get_index()]->get_event())) < 0)
 113         {
 114                 ERROR(binder_interface, "%s: Operation goes wrong for signal: %s", __FUNCTION__, can_subscription->get_name().c_str());
 115                 return -1;
 116         }
 117         return 0;
 118 }
 119
 120 static int create_event_handle(std::shared_ptr<low_can_subscription_t>& can_subscription, std::map<int, std::shared_ptr<low_can_subscription_t> >& s)
 121 {
 122         int sub_index = can_subscription->get_index();
 123         can_subscription->set_event(afb_daemon_make_event(binder_interface->daemon, can_subscription->get_name().c_str()));
 124         s[sub_index] = can_subscription;
 125         if (!afb_event_is_valid(s[sub_index]->get_event()))
 126         {
 127                 ERROR(binder_interface, "%s: Can't create an event for %s, something goes wrong.", __FUNCTION__, can_subscription->get_name().c_str());
 128                 return -1;
 129         }
 130         return 0;
 131 }
 132
 133 /// @brief Will determine if it is needed or not to create the event handle and checks it to be sure that
 134 /// we got a valid afb_event to get subscribe or unsubscribe. Then launch the subscription or unsubscription
 135 /// against the application framework using that event handle.
 136 static int subscribe_unsubscribe_signal(struct afb_req request, bool subscribe, std::shared_ptr<low_can_subscription_t>& can_subscription, std::map<int, std::shared_ptr<low_can_subscription_t> >& s)
 137 {
 138         int ret;
 139         int sub_index = can_subscription->get_index();
 140
 141         if (can_subscription && s.find(sub_index) != s.end())
 142         {
 143                 if (!afb_event_is_valid(s[sub_index]->get_event()) && !subscribe)
 144                 {
 145                         NOTICE(binder_interface, "%s: Event isn't valid, no need to unsubscribed.", __FUNCTION__);
 146                         ret = -1;
 147                 }
 148         }
 149         else
 150         {
 151                 /* Event doesn't exist , so let's create it */
 152                 can_subscription->set_event({nullptr, nullptr});
 153                 s[sub_index] = can_subscription;
 154                 ret = create_event_handle(can_subscription, s);
 155         }
 156
 157         // Check whether or not the event handler has been correctly created and
 158         // make the subscription/unsubscription operation is so.
 159         if (ret < 0)
 160                 return ret;
 161         return make_subscription_unsubscription(request, can_subscription, s, subscribe);
 162 }
 163
 164 static int add_to_event_loop(std::shared_ptr<low_can_subscription_t>& can_subscription)
 165 {
 166                 struct sd_event_source* event_source = nullptr;
 167                 return ( sd_event_add_io(afb_daemon_get_event_loop(binder_interface->daemon),
 168                         &event_source,
 169                         can_subscription->get_socket().socket(),
 170                         EPOLLIN,
 171                         read_message,
 172                         can_subscription.get()));
 173 }
 174
 175 static int subscribe_unsubscribe_diagnostic_messages(struct afb_req request, bool subscribe, std::vector<std::shared_ptr<diagnostic_message_t> > diagnostic_messages, struct event_filter_t& event_filter, std::map<int, std::shared_ptr<low_can_subscription_t> >& s)
 176 {
 177         int rets = 0;
 178         application_t& app = application_t::instance();
 179         diagnostic_manager_t& diag_m = app.get_diagnostic_manager();
 180
 181         for(const auto& sig : diagnostic_messages)
 182         {
 183                 DiagnosticRequest* diag_req = new DiagnosticRequest(sig->build_diagnostic_request());
 184                 event_filter.frequency = std::isnan(event_filter.frequency) ? sig->get_frequency() : event_filter.frequency;
 185                 std::shared_ptr<low_can_subscription_t> can_subscription;
 186
 187                 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());});
 188                 can_subscription = it != s.end() ?
 189                         it->second :
 190                         std::make_shared<low_can_subscription_t>(low_can_subscription_t(event_filter));
 191                 // If the requested diagnostic message isn't supported by the car then unsubcribe it
 192                 // no matter what we want, worse case will be a fail unsubscription but at least we don't
 193                 // poll a PID for nothing.
 194                 //TODO: Adding callback requesting ignition status:     diag_req, sig.c_str(), false, diagnostic_message_t::decode_obd2_response, diagnostic_message_t::check_ignition_status, frequency);
 195                 if(sig->get_supported() && subscribe)
 196                 {
 197                         diag_m.add_recurring_request(diag_req, sig->get_name().c_str(), false, sig->get_decoder(), sig->get_callback(), event_filter.frequency);
 198                         if(can_subscription->create_rx_filter(sig) < 0)
 199                                 {return -1;}
 200                         DEBUG(binder_interface, "%s: Signal: %s subscribed", __FUNCTION__, sig->get_name().c_str());
 201                         if(it == s.end() && add_to_event_loop(can_subscription) < 0)
 202                         {
 203                                 diag_m.cleanup_request(
 204                                         diag_m.find_recurring_request(*diag_req), true);
 205                                 WARNING(binder_interface, "%s: signal: %s isn't supported. Canceling operation.", __FUNCTION__,  sig->get_name().c_str());
 206                                 return -1;
 207                         }
 208                 }
 209                 else
 210                 {
 211                         diag_m.cleanup_request(
 212                                         diag_m.find_recurring_request(*diag_req), true);
 213                         if(sig->get_supported())
 214                         {DEBUG(binder_interface, "%s: %s cancelled due to unsubscribe", __FUNCTION__, sig->get_name().c_str());}
 215                         else
 216                         {
 217                                 WARNING(binder_interface, "%s: signal: %s isn't supported. Canceling operation.", __FUNCTION__, sig->get_name().c_str());
 218                                 return -1;
 219                         }
 220                 }
 221                 int ret = subscribe_unsubscribe_signal(request, subscribe, can_subscription, s);
 222                 if(ret < 0)
 223                         return ret;
 224
 225                 rets++;
 226         }
 227
 228         return rets;
 229 }
 230
 231 static int subscribe_unsubscribe_can_signals(struct afb_req request, bool subscribe, std::vector<std::shared_ptr<can_signal_t> > can_signals, struct event_filter_t& event_filter, std::map<int, std::shared_ptr<low_can_subscription_t> >& s)
 232 {
 233         int rets = 0;
 234         for(const auto& sig: can_signals)
 235         {
 236                 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_can_signal() == sig; });
 237                 std::shared_ptr<low_can_subscription_t> can_subscription;
 238                 if(it != s.end())
 239                 {
 240                          can_subscription = it->second;
 241                 }
 242                 else
 243                 {
 244                          can_subscription = std::make_shared<low_can_subscription_t>(low_can_subscription_t(event_filter));
 245                         if(can_subscription->create_rx_filter(sig) < 0)
 246                                 {return -1;}
 247                 }
 248
 249                 if(subscribe_unsubscribe_signal(request, subscribe, can_subscription, s) < 0)
 250                         {return -1;}
 251
 252                 if(add_to_event_loop(can_subscription) < 0)
 253                         {return -1;}
 254                 rets++;
 255                 DEBUG(binder_interface, "%s: signal: %s subscribed", __FUNCTION__, sig->get_name().c_str());
 256         }
 257         return rets;
 258 }
 259
 260 ///
 261 /// @brief subscribe to all signals in the vector signals
 262 ///
 263 /// @param[in] afb_req request : contain original request use to subscribe or unsubscribe
 264 /// @param[in] subscribe boolean value used to chose between a subscription operation or an unsubscription
 265 /// @param[in] signals -  struct containing vectors with can_signal_t and diagnostic_messages to subscribe
 266 ///
 267 /// @return Number of correctly subscribed signal
 268 ///
 269 static int subscribe_unsubscribe_signals(struct afb_req request, bool subscribe, const struct utils::signals_found& signals, struct event_filter_t& event_filter)
 270 {
 271         int rets = 0;
 272         utils::signals_manager_t& sm = utils::signals_manager_t::instance();
 273
 274         std::lock_guard<std::mutex> subscribed_signals_lock(sm.get_subscribed_signals_mutex());
 275         std::map<int, std::shared_ptr<low_can_subscription_t> >& s = sm.get_subscribed_signals();
 276
 277         rets += subscribe_unsubscribe_diagnostic_messages(request, subscribe, signals.diagnostic_messages, event_filter, s);
 278         rets += subscribe_unsubscribe_can_signals(request, subscribe, signals.can_signals, event_filter, s);
 279
 280         return rets;
 281 }
 282
 283 static int one_subscribe_unsubscribe(struct afb_req request, bool subscribe, const std::string& tag, json_object* args)
 284 {
 285         int ret = 0;
 286         struct event_filter_t event_filter;
 287         struct json_object  *filter, *obj;
 288         struct utils::signals_found sf;
 289
 290         // computes the filter
 291         if (json_object_object_get_ex(args, "filter", &filter))
 292         {
 293                 if (json_object_object_get_ex(filter, "frequency", &obj)
 294                 && (json_object_is_type(obj, json_type_double) || json_object_is_type(obj, json_type_int)))
 295                 {
 296                         event_filter.frequency = (float)json_object_get_double(obj);
 297                         ret += 1;
 298                 }
 299                 if (json_object_object_get_ex(filter, "min", &obj)
 300                 && (json_object_is_type(obj, json_type_double) || json_object_is_type(obj, json_type_int)))
 301                 {
 302                         event_filter.min = (float)json_object_get_double(obj);
 303                         ret += 2;
 304                 }
 305                 if (json_object_object_get_ex(filter, "max", &obj)
 306                 && (json_object_is_type(obj, json_type_double) || json_object_is_type(obj, json_type_int)))
 307                 {
 308                         event_filter.max = (float)json_object_get_double(obj);
 309                         ret += 4;
 310                 }
 311         }
 312
 313         // subscribe or unsubscribe
 314         openxc_DynamicField search_key = build_DynamicField(tag);
 315         sf = utils::signals_manager_t::instance().find_signals(search_key);
 316         if (sf.can_signals.empty() && sf.diagnostic_messages.empty())
 317                 NOTICE(binder_interface, "%s: No signal(s) found for %s.", __FUNCTION__, tag.c_str());
 318         else
 319                 ret = subscribe_unsubscribe_signals(request, subscribe, sf, event_filter);
 320
 321         return ret;
 322 }
 323
 324 static void do_subscribe_unsubscribe(struct afb_req request, bool subscribe)
 325 {
 326         int i, n, rc, rc2;
 327         struct json_object *args, *event, *x;
 328
 329         args = afb_req_json(request);
 330         if (args == NULL || !json_object_object_get_ex(args, "event", &event))
 331         {
 332                 rc = one_subscribe_unsubscribe(request, subscribe, "*", args);
 333         }
 334         else if (json_object_get_type(event) != json_type_array)
 335         {
 336                 rc = one_subscribe_unsubscribe(request, subscribe, json_object_get_string(event), args);
 337         }
 338         else
 339         {
 340                 rc = 0;
 341                 n = json_object_array_length(event);
 342                 for (i = 0 ; i < n ; i++)
 343                 {
 344                         x = json_object_array_get_idx(event, i);
 345                         rc2 = one_subscribe_unsubscribe(request, subscribe, json_object_get_string(x), args);
 346                         if (rc >= 0)
 347                                 rc = rc2 >= 0 ? rc + rc2 : rc2;
 348                 }
 349         }
 350
 351         if (rc >= 0)
 352                 afb_req_success(request, NULL, NULL);
 353         else
 354                 afb_req_fail(request, "error", NULL);
 355 }
 356
 357 void subscribe(struct afb_req request)
 358 {
 359         do_subscribe_unsubscribe(request, true);
 360 }
 361
 362 void unsubscribe(struct afb_req request)
 363 {
 364         do_subscribe_unsubscribe(request, false);
 365 }