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