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 #define MICRO 1000000
  46
  47 // Interface between the daemon and the binding
  48 const struct afb_binding_interface *binder_interface;
  49
  50 /********************************************************************************
  51 *
  52 *               Subscription and unsubscription
  53 *
  54 *********************************************************************************/
  55
  56 static int make_subscription_unsubscription(struct afb_req request, const std::string& sig_name, std::map<std::string, struct afb_event>& s, bool subscribe)
  57 {
  58         /* Make the subscription or unsubscription to the event */
  59         if (((subscribe ? afb_req_subscribe : afb_req_unsubscribe)(request, s[sig_name.c_str()])) < 0)
  60         {
  61                 ERROR(binder_interface, "Operation goes wrong for signal: %s", sig_name);
  62                 return 0;
  63         }
  64         return 1;
  65
  66 }
  67
  68 static int create_event_handle(const std::string& sig_name, std::map<std::string, struct afb_event>& s)
  69 {
  70         s[sig_name] = afb_daemon_make_event(binder_interface->daemon, sig_name.c_str());
  71         if (!afb_event_is_valid(s[sig_name]))
  72         {
  73                 ERROR(binder_interface, "Can't create an event, something goes wrong.");
  74                 return 0;
  75         }
  76         return 1;
  77 }
  78
  79 static int subscribe_unsubscribe_signal(struct afb_req request, bool subscribe, const std::string& sig)
  80 {
  81         int ret;
  82
  83         std::lock_guard<std::mutex> subscribed_signals_lock(get_subscribed_signals_mutex());
  84         std::map<std::string, struct afb_event>& s = get_subscribed_signals();
  85         if (s.find(sig) != s.end() && !afb_event_is_valid(s[sig]))
  86         {
  87                 if(!subscribe)
  88                 {
  89                         NOTICE(binder_interface, "Event isn't valid, it can't be unsubscribed.");
  90                         ret = -1;
  91                 }
  92                 else
  93                 {
  94                         /* Event it isn't valid annymore, recreate it */
  95                         ret = create_event_handle(sig, s);
  96                 }
  97         }
  98         else
  99         {
 100                 /* Event doesn't exist , so let's create it */
 101                 struct afb_event empty_event = {nullptr, nullptr};
 102                 subscribed_signals[sig] = empty_event;
 103                 ret = create_event_handle(sig, s);
 104         }
 105
 106         /* Check whether or not the event handler has been correctly created and
 107          * make the subscription/unsubscription operation is so.
 108          */
 109         if (ret <= 0)
 110                 return ret;
 111         return make_subscription_unsubscription(request, sig, s, subscribe);
 112 }
 113
 114 /**
 115  * @fn static int subscribe_unsubscribe_signals(struct afb_req request, bool subscribe, const std::vector<can_signal_t>& signals)
 116  * @brief subscribe to all signals in the vector signals
 117  *
 118  * @param[in] afb_req request : contain original request use to subscribe or unsubscribe
 119  * @param[in] subscribe boolean value used to chose between a subscription operation or an unsubscription
 120  * @param[in] can_signal_t  vector with can_signal_t to subscribe
 121  *
 122  * @return Number of correctly subscribed signal
 123  */
 124 static int subscribe_unsubscribe_signals(struct afb_req request, bool subscribe, const std::vector<std::string>& signals)
 125 {
 126         int rets = 0;
 127         sd_event_source *source;
 128
 129         //TODO: Implement way to dynamically call the right function no matter
 130         // how much signals types we have.
 131
 132         for(const std::string& sig : signals)
 133         {
 134                 int ret;
 135                 if (active_diagnostic_request_t::is_diagnostic_signal(sig))
 136                 {
 137                         std::vector<obd2_signal_t*> found;
 138                         configuration_t::instance().find_obd2_signals(build_DynamicField(sig), found);
 139                         int frequency = found.front()->get_frequency();
 140                         DiagnosticRequest* diag_req = new DiagnosticRequest(found.front()->build_diagnostic_request());
 141                         configuration_t::instance().get_diagnostic_manager().add_recurring_request(
 142                                 diag_req, sig.c_str(), false, obd2_signal_t::decode_obd2_response, nullptr, (float)frequency);
 143                                 //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);
 144                         sd_event_add_time(afb_daemon_get_event_loop(binder_interface->daemon), &source, CLOCK_MONOTONIC, frequency*MICRO, 0,
 145                                                                 configuration_t::instance().get_diagnostic_manager().send_request, diag_req);
 146                 }
 147
 148                 ret = subscribe_unsubscribe_signal(request, subscribe, sig);
 149                 if(ret <= 0)
 150                         return ret;
 151
 152                 rets++;
 153                 DEBUG(binder_interface, "Signal: %s subscribed", sig.c_str());
 154         }
 155         return rets;
 156 }
 157
 158 static int subscribe_unsubscribe_name(struct afb_req request, bool subscribe, const char *name)
 159 {
 160         std::vector<std::string> signals;
 161         int ret = 0;
 162
 163         openxc_DynamicField search_key = build_DynamicField(std::string(name));
 164         signals = find_signals(search_key);
 165         if (signals.empty())
 166                 ret = 0;
 167
 168         ret = subscribe_unsubscribe_signals(request, subscribe, signals);
 169         NOTICE(binder_interface, "Subscribed correctly to %d/%d signal(s).", ret, (int)signals.size());
 170
 171         return ret;
 172 }
 173
 174 static void subscribe_unsubscribe(struct afb_req request, bool subscribe)
 175 {
 176         int ok, i, n;
 177         struct json_object *args, *a, *x;
 178
 179         /* makes the subscription/unsubscription */
 180         args = afb_req_json(request);
 181         if (args == NULL || !json_object_object_get_ex(args, "event", &a)) {
 182                 ok = subscribe_unsubscribe_name(request, subscribe, "*");
 183         } else if (json_object_get_type(a) != json_type_array) {
 184                 ok = subscribe_unsubscribe_name(request, subscribe, json_object_get_string(a));
 185         } else {
 186                 n = json_object_array_length(a);
 187                 ok = 0;
 188                 for (i = 0 ; i < n ; i++) {
 189                         x = json_object_array_get_idx(a, i);
 190                         if (subscribe_unsubscribe_name(request, subscribe, json_object_get_string(x)))
 191                                 ok++;
 192                 }
 193                 ok = (ok == n);
 194         }
 195
 196         /* send the report */
 197         if (ok)
 198                 afb_req_success(request, NULL, NULL);
 199         else
 200                 afb_req_fail(request, "error", NULL);
 201 }
 202
 203 extern "C"
 204 {
 205         static void subscribe(struct afb_req request)
 206         {
 207                 subscribe_unsubscribe(request, true);
 208         }
 209
 210         static void unsubscribe(struct afb_req request)
 211         {
 212                 subscribe_unsubscribe(request, false);
 213         }
 214
 215         static const struct afb_verb_desc_v1 verbs[]=
 216         {
 217                 { .name= "subscribe",   .session= AFB_SESSION_NONE, .callback= subscribe,       .info= "subscribe to notification of CAN bus messages." },
 218                 { .name= "unsubscribe", .session= AFB_SESSION_NONE, .callback= unsubscribe,     .info= "unsubscribe a previous subscription." }
 219         };
 220
 221         static const struct afb_binding binding_desc {
 222                 AFB_BINDING_VERSION_1,
 223                 {
 224                         "Low level CAN bus service",
 225                         "low-can",
 226                         verbs
 227                 }
 228         };
 229
 230         const struct afb_binding *afbBindingV1Register (const struct afb_binding_interface *itf)
 231         {
 232                 binder_interface = itf;
 233
 234                 return &binding_desc;
 235         }
 236
 237         /**
 238         * @brief Initialize the binding.
 239         *
 240         * @param[in] service Structure which represent the Application Framework Binder.
 241         *
 242         * @return Exit code, zero if success.
 243         */
 244         int afbBindingV1ServiceInit(struct afb_service service)
 245         {
 246                 can_bus_t& can_bus_manager = configuration_t::instance().get_can_bus_manager();
 247
 248                 /// Initialize CAN socket
 249                 if(can_bus_manager.init_can_dev() == 0)
 250                 {
 251                         can_bus_manager.start_threads();
 252                         return 0;
 253                 }
 254
 255                 /// Initialize Diagnostic manager that will handle obd2 requests.
 256                 /// We pass by default the first CAN bus device to its Initialization.
 257                 /// TODO: be able to choose the CAN bus device that will be use as Diagnostic bus.
 258                 configuration_t::instance().get_diagnostic_manager().initialize(can_bus_manager.get_can_devices().front());
 259
 260                 ERROR(binder_interface, "There was something wrong with CAN device Initialization. Check your config file maybe");
 261                 return 1;
 262         }
 263 };