src/low-can-binding.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-binding.hpp"
  20
  21 #include <queue>
  22 #include <mutex>
  23 #include <vector>
  24 #include <thread>
  25 #include <time.h>
  26 #include <linux/can.h>
  27 #include <json-c/json.h>
  28 #include <systemd/sd-event.h>
  29
  30 #include "openxc.pb.h"
  31 #include "configuration.hpp"
  32 #include "can/can-bus.hpp"
  33 #include "can/can-signals.hpp"
  34 #include "can/can-message.hpp"
  35 #include "utils/timer.hpp"
  36 #include "utils/signals.hpp"
  37 #include "obd2/obd2-signals.hpp"
  38 #include "utils/openxc-utils.hpp"
  39
  40 extern "C"
  41 {
  42         #include <afb/afb-service-itf.h>
  43 };
  44
  45 // Interface between the daemon and the binding
  46 const struct afb_binding_interface *binder_interface;
  47
  48 /********************************************************************************
  49 *
  50 *               Subscription and unsubscription
  51 *
  52 *********************************************************************************/
  53
  54 static int make_subscription_unsubscription(struct afb_req request, const std::string& sig_name, std::map<std::string, struct afb_event>& s, bool subscribe)
  55 {
  56         /* Make the subscription or unsubscription to the event */
  57         if (((subscribe ? afb_req_subscribe : afb_req_unsubscribe)(request, s[sig_name.c_str()])) < 0)
  58         {
  59                 ERROR(binder_interface, "Operation goes wrong for signal: %s", sig_name);
  60                 return 0;
  61         }
  62         return 1;
  63
  64 }
  65
  66 static int create_event_handle(const std::string& sig_name, std::map<std::string, struct afb_event>& s)
  67 {
  68         s[sig_name] = afb_daemon_make_event(binder_interface->daemon, sig_name.c_str());
  69         if (!afb_event_is_valid(s[sig_name]))
  70         {
  71                 ERROR(binder_interface, "Can't create an event, something goes wrong.");
  72                 return 0;
  73         }
  74         return 1;
  75 }
  76
  77 static int subscribe_unsubscribe_signal(struct afb_req request, bool subscribe, const std::string& sig, DiagnosticRequest* diag_req, int frequency)
  78 {
  79         int ret;
  80         sd_event_source *source;
  81
  82         std::lock_guard<std::mutex> subscribed_signals_lock(get_subscribed_signals_mutex());
  83         std::map<std::string, struct afb_event>& s = get_subscribed_signals();
  84         if (s.find(sig) != s.end() && !afb_event_is_valid(s[sig]))
  85         {
  86                 if(!subscribe)
  87                 {
  88                         NOTICE(binder_interface, "Event isn't valid, it can't be unsubscribed.");
  89                         ret = -1;
  90                 }
  91                 else
  92                 {
  93                         /* Event it isn't valid anymore, recreate it */
  94                         sd_event_add_time(afb_daemon_get_event_loop(binder_interface->daemon), &source, CLOCK_MONOTONIC, frequency, 0,
  95                                                 configuration_t::instance().get_diagnostic_manager().send_request, diag_req);
  96                         ret = create_event_handle(sig, s);
  97                 }
  98         }
  99         else
 100         {
 101                 /* Event doesn't exist , so let's create it */
 102                 struct afb_event empty_event = {nullptr, nullptr};
 103                 subscribed_signals[sig] = empty_event;
 104                 ret = create_event_handle(sig, s);
 105         }
 106
 107         /* Check whether or not the event handler has been correctly created and
 108          * make the subscription/unsubscription operation is so.
 109          */
 110         if (ret <= 0)
 111                 return ret;
 112         return make_subscription_unsubscription(request, sig, s, subscribe);
 113 }
 114
 115 static int subscribe_unsubscribe_signal(struct afb_req request, bool subscribe, const std::string& sig)
 116 {
 117         int ret;
 118
 119         std::lock_guard<std::mutex> subscribed_signals_lock(get_subscribed_signals_mutex());
 120         std::map<std::string, struct afb_event>& s = get_subscribed_signals();
 121         if (s.find(sig) != s.end() && !afb_event_is_valid(s[sig]))
 122         {
 123                 if(!subscribe)
 124                 {
 125                         NOTICE(binder_interface, "Event isn't valid, it can't be unsubscribed.");
 126                         ret = -1;
 127                 }
 128                 else
 129                 {
 130                         /* Event it isn't valid annymore, recreate it */
 131                         ret = create_event_handle(sig, s);
 132                 }
 133         }
 134         else
 135         {
 136                 /* Event doesn't exist , so let's create it */
 137                 struct afb_event empty_event = {nullptr, nullptr};
 138                 subscribed_signals[sig] = empty_event;
 139                 ret = create_event_handle(sig, s);
 140         }
 141
 142         /* Check whether or not the event handler has been correctly created and
 143          * make the subscription/unsubscription operation is so.
 144          */
 145         if (ret <= 0)
 146                 return ret;
 147         return make_subscription_unsubscription(request, sig, s, subscribe);
 148 }
 149
 150 /**
 151  * @fn static int subscribe_unsubscribe_signals(struct afb_req request, bool subscribe, const std::vector<can_signal_t>& signals)
 152  * @brief subscribe to all signals in the vector signals
 153  *
 154  * @param[in] afb_req request : contain original request use to subscribe or unsubscribe
 155  * @param[in] subscribe boolean value used to chose between a subscription operation or an unsubscription
 156  * @param[in] can_signal_t  vector with can_signal_t to subscribe
 157  *
 158  * @return Number of correctly subscribed signal
 159  */
 160 static int subscribe_unsubscribe_signals(struct afb_req request, bool subscribe, const std::vector<std::string>& signals)
 161 {
 162         int rets = 0;
 163         //TODO: Implement way to dynamically call the right function no matter
 164         // how much signals types we have.
 165         const std::string& can_prefix = configuration_t::instance().get_can_signals().front().get_prefix();
 166         const std::string& obd2_prefix = configuration_t::instance().get_obd2_signals().front().get_prefix();
 167
 168         for(const std::string& sig : signals)
 169         {
 170                 int ret;
 171                 if (sig.find_first_of(can_prefix.c_str(), 0, can_prefix.size()))
 172                         ret = subscribe_unsubscribe_signal(request, subscribe, sig);
 173                 else if (sig.find_first_of(obd2_prefix.c_str(), 0, obd2_prefix.size()))
 174                 {
 175                         std::vector<obd2_signal_t*> found;
 176                         configuration_t::instance().find_obd2_signals(build_DynamicField(sig), found);
 177                         int frequency = found.front()->get_frequency();
 178                         DiagnosticRequest* diag_req = new DiagnosticRequest(found.front()->build_diagnostic_request());
 179                         configuration_t::instance().get_diagnostic_manager().add_recurring_request(
 180                                 diag_req, sig.c_str(), false, obd2_signal_t::decode_obd2_response, nullptr, (float)frequency);
 181                                 //TODO: Adding callback requesting ignition status:     diag_req, sig.c_str(), false, obd2_signal_t::decode_obd2_response, obd2_signal_t::check_ignition_status, frequency);
 182                         ret = subscribe_unsubscribe_signal(request, subscribe, sig, diag_req,frequency);
 183                 }
 184                 else
 185                         ret = -1;
 186
 187                 if(ret <= 0)
 188                         return ret;
 189                 rets++;
 190                 DEBUG(binder_interface, "Signal: %s subscribed", sig.c_str());
 191         }
 192         return rets;
 193 }
 194
 195 static int subscribe_unsubscribe_name(struct afb_req request, bool subscribe, const char *name)
 196 {
 197         std::vector<std::string> signals;
 198         int ret = 0;
 199
 200         openxc_DynamicField search_key = build_DynamicField(std::string(name));
 201         signals = find_signals(search_key);
 202         if (signals.empty())
 203                 ret = 0;
 204
 205         ret = subscribe_unsubscribe_signals(request, subscribe, signals);
 206         NOTICE(binder_interface, "Subscribed correctly to %d/%d signal(s).", ret, (int)signals.size());
 207
 208         return ret;
 209 }
 210
 211 static void subscribe_unsubscribe(struct afb_req request, bool subscribe)
 212 {
 213         int ok, i, n;
 214         struct json_object *args, *a, *x;
 215
 216         /* makes the subscription/unsubscription */
 217         args = afb_req_json(request);
 218         if (args == NULL || !json_object_object_get_ex(args, "event", &a)) {
 219                 ok = subscribe_unsubscribe_name(request, subscribe, "*");
 220         } else if (json_object_get_type(a) != json_type_array) {
 221                 ok = subscribe_unsubscribe_name(request, subscribe, json_object_get_string(a));
 222         } else {
 223                 n = json_object_array_length(a);
 224                 ok = 0;
 225                 for (i = 0 ; i < n ; i++) {
 226                         x = json_object_array_get_idx(a, i);
 227                         if (subscribe_unsubscribe_name(request, subscribe, json_object_get_string(x)))
 228                                 ok++;
 229                 }
 230                 ok = (ok == n);
 231         }
 232
 233         /* send the report */
 234         if (ok)
 235                 afb_req_success(request, NULL, NULL);
 236         else
 237                 afb_req_fail(request, "error", NULL);
 238 }
 239
 240 extern "C"
 241 {
 242         static void subscribe(struct afb_req request)
 243         {
 244                 subscribe_unsubscribe(request, true);
 245         }
 246
 247         static void unsubscribe(struct afb_req request)
 248         {
 249                 subscribe_unsubscribe(request, false);
 250         }
 251
 252         static const struct afb_verb_desc_v1 verbs[]=
 253         {
 254                 { .name= "subscribe",   .session= AFB_SESSION_NONE, .callback= subscribe,       .info= "subscribe to notification of CAN bus messages." },
 255                 { .name= "unsubscribe", .session= AFB_SESSION_NONE, .callback= unsubscribe,     .info= "unsubscribe a previous subscription." }
 256         };
 257
 258         static const struct afb_binding binding_desc {
 259                 AFB_BINDING_VERSION_1,
 260                 {
 261                         "Low level CAN bus service",
 262                         "low-can",
 263                         verbs
 264                 }
 265         };
 266
 267         const struct afb_binding *afbBindingV1Register (const struct afb_binding_interface *itf)
 268         {
 269                 binder_interface = itf;
 270
 271                 return &binding_desc;
 272         }
 273
 274         /**
 275         * @brief Initialize the binding.
 276         *
 277         * @param[in] service Structure which represent the Application Framework Binder.
 278         *
 279         * @return Exit code, zero if success.
 280         */
 281         int afbBindingV1ServiceInit(struct afb_service service)
 282         {
 283                 can_bus_t& can_bus_manager = configuration_t::instance().get_can_bus_manager();
 284
 285                 /// Initialize CAN socket
 286                 if(can_bus_manager.init_can_dev() == 0)
 287                 {
 288                         can_bus_manager.start_threads();
 289                         return 0;
 290                 }
 291
 292                 /// Initialize Diagnostic manager that will handle obd2 requests
 293                 diagnostic_manager_t& diag_manager = configuration_t::instance().get_diagnostic_manager();
 294                 diag_manager.initialize(can_bus_manager.get_can_devices().front());
 295
 296                 ERROR(binder_interface, "There was something wrong with CAN device Initialization. Check your config file maybe");
 297                 return 1;
 298         }
 299 };