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 <unistd.h>
  20 #include <sys/types.h>
  21 #include <sys/socket.h>
  22 #include <sys/ioctl.h>
  23 #include <net/if.h>
  24 #include <linux/can.h>
  25 #include <linux/can/raw.h>
  26 #include <fcntl.h>
  27 #include <systemd/sd-event.h>
  28 #include <errno.h>
  29 #include <vector>
  30 #include <map>
  31 #include <queue>
  32 #include <string>
  33 #include <functional>
  34 #include <memory>
  35 #include <thread>
  36
  37 #include <json-c/json.h>
  38 #include <openxc.pb.h>
  39
  40 #include "low-can-binding.hpp"
  41 #include "openxc-utils.hpp"
  42 #include "obd2.hpp"
  43 #include "can-utils.hpp"
  44 #include "can-signals.hpp"
  45
  46 /********************************************************************************
  47 *
  48 *               Event management
  49 *
  50 *********************************************************************************/
  51
  52 /********************************************************************************
  53 *
  54 *               Subscription and unsubscription
  55 *
  56 *********************************************************************************/
  57
  58 static int subscribe_unsubscribe_signal(struct afb_req request, bool subscribe, const CanSignal& sig)
  59 {
  60         int ret;
  61
  62         const auto& ss_i = subscribed_signals.find(sig.genericName);
  63         if (ss_i != subscribed_signals.end())
  64         {
  65                 if(!afb_event_is_valid(ss_i->second))
  66                 {
  67                         if(!subscribe)
  68                         {
  69                                 NOTICE(interface, "Event isn't valid, it can't be unsubscribed.");
  70                                 ret = 1;
  71                         }
  72                         else
  73                         {
  74                                 ss_i->second = afb_daemon_make_event(interface->daemon, ss_i->first.c_str());
  75                                 if (!afb_event_is_valid(ss_i->second))
  76                                 {
  77                                         ERROR(interface, "Can't create an event, something goes wrong.");
  78                                         ret = 0;
  79                                 }
  80                         }
  81                 }
  82         }
  83         else
  84         {
  85                 subscribed_signals[sig.genericName] = afb_daemon_make_event(interface->daemon, sig.genericName);
  86                 if (!afb_event_is_valid(ss_i->second))
  87                 {
  88                         ERROR(interface, "Can't create an event, something goes wrong.");
  89                         ret = 0;
  90                 }
  91         }
  92
  93         if (((subscribe ? afb_req_subscribe : afb_req_unsubscribe)(request, subscribed_signals[sig.genericName])) < 0)
  94         {
  95                 ERROR(interface, "Operation goes wrong for signal: %s", sig.genericName);
  96                 ret = 0;
  97         }
  98         else
  99                 ret = 1;
 100
 101         return ret;
 102 }
 103
 104 static int subscribe_unsubscribe_signals(struct afb_req request, bool subscribe, const std::vector<CanSignal>& signals)
 105 {
 106         int ret;
 107
 108         // TODO: lock the subscribed_signals when insert/remove
 109         for(const auto& signal_i : signals)
 110         {
 111                 ret = subscribe_unsubscribe_signal(request, subscribe, signal_i);
 112                 if(ret == 0)
 113                         return ret;
 114         }
 115 }
 116
 117 static int subscribe_unsubscribe_all(struct afb_req request, bool subscribe)
 118 {
 119         int e = 0;
 120
 121         //for (const auto& sig : SIGNALS)
 122         //      e += !subscribe_unsubscribe_signals(request, subscribe, sig);
 123         e += !subscribe_unsubscribe_signals(request, subscribe, SIGNALS[MESSAGE_SET_ID]);
 124
 125         return e == 0;
 126 }
 127
 128 static int subscribe_unsubscribe_name(struct afb_req request, bool subscribe, const char *name)
 129 {
 130         std::vector<CanSignal> sig;
 131         int ret = 0;
 132
 133         if (!::strcmp(name, "*"))
 134                 ret = subscribe_unsubscribe_all(request, subscribe);
 135         else
 136         {
 137                 //if(obd2_handler_c.is_obd2_signal(name))
 138                 if(false)
 139                 {
 140                 // TODO
 141                 }
 142                 else
 143                 {
 144                         openxc_DynamicField search_key = build_DynamicField(name);
 145                         sig = find_can_signals(search_key);
 146                         if (sig.empty())
 147                                 ret = 0;
 148                 }
 149                 ret = subscribe_unsubscribe_signals(request, subscribe, sig);
 150         }
 151         return ret;
 152 }
 153
 154 static void subscribe_unsubscribe(struct afb_req request, bool subscribe)
 155 {
 156         int ok, i, n;
 157         struct json_object *args, *a, *x;
 158
 159         /* makes the subscription/unsubscription */
 160         args = afb_req_json(request);
 161         if (args == NULL || !json_object_object_get_ex(args, "event", &a)) {
 162                 ok = subscribe_unsubscribe_all(request, subscribe);
 163         } else if (json_object_get_type(a) != json_type_array) {
 164                 ok = subscribe_unsubscribe_name(request, subscribe, json_object_get_string(a));
 165         } else {
 166                 n = json_object_array_length(a);
 167                 ok = 0;
 168                 for (i = 0 ; i < n ; i++) {
 169                         x = json_object_array_get_idx(a, i);
 170                         if (subscribe_unsubscribe_name(request, subscribe, json_object_get_string(x)))
 171                                 ok++;
 172                 }
 173                 ok = (ok == n);
 174         }
 175
 176         /* send the report */
 177         if (ok)
 178                 afb_req_success(request, NULL, NULL);
 179         else
 180                 afb_req_fail(request, "error", NULL);
 181 }
 182
 183 static const struct afb_verb_desc_v1 verbs[]=
 184 {
 185         { .name= "subscribe",   .session= AFB_SESSION_NONE, .callback= subscribe,       .info= "subscribe to notification of CAN bus messages." },
 186         { .name= "unsubscribe", .session= AFB_SESSION_NONE, .callback= unsubscribe,     .info= "unsubscribe a previous subscription." }
 187 };
 188
 189 static const struct afb_binding binding_desc {
 190         AFB_BINDING_VERSION_1,
 191         {
 192                 "CAN bus service",
 193                 "can",
 194                 verbs
 195         }
 196 };
 197
 198 extern "C"
 199 {
 200         static void subscribe(struct afb_req request)
 201         {
 202                 subscribe_unsubscribe(request, true);
 203         }
 204
 205         static void unsubscribe(struct afb_req request)
 206         {
 207                 subscribe_unsubscribe(request, false);
 208         }
 209
 210         const struct afb_binding *afbBindingV1Register (const struct afb_binding_interface *itf)
 211         {
 212                 interface = itf;
 213
 214                 return &binding_desc;
 215         }
 216
 217         /**
 218         * @brief Initialize the binding.
 219         *
 220         * @param[in] service Structure which represent the Application Framework Binder.
 221         *
 222         * @return Exit code, zero if success.
 223         */
 224         int afbBindingV1ServiceInit(struct afb_service service)
 225         {
 226                 int fd_conf;
 227                 fd_conf = afb_daemon_rootdir_open_locale(interface->daemon, "can_bus.json", O_RDONLY, NULL);
 228
 229                 /* Open CAN socket */
 230                 can_bus_t can_bus_handler(interface, fd_conf);
 231                 if(can_bus_handler.init_can_dev() == 0)
 232                 {
 233                         can_bus_handler.start_threads();
 234                         return 0;
 235                 }
 236
 237                 return 1;
 238         }
 239 }