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