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 "configuration.hpp"
  31 #include "../can/can-bus.hpp"
  32 #include "../can/can-signals.hpp"
  33 #include "../can/can-message.hpp"
  34 #include "../utils/timer.hpp"
  35 #include "../utils/signals.hpp"
  36 #include "../diagnostic/diagnostic-message.hpp"
  37 #include "../utils/openxc-utils.hpp"
  38
  39 extern "C"
  40 {
  41         #include <afb/afb-service-itf.h>
  42 };
  43
  44 void on_no_clients(std::string message)
  45 {
  46         DiagnosticRequest* diag_req = configuration_t::instance().get_request_from_diagnostic_message(message);
  47         if(diag_req != nullptr)
  48         {
  49                 active_diagnostic_request_t* adr = configuration_t::instance().get_diagnostic_manager().find_recurring_request(diag_req);
  50                 if( adr != nullptr)
  51                         configuration_t::instance().get_diagnostic_manager().cleanup_request(adr, true);
  52         }
  53 }
  54
  55 int read(sd_event_source *s, int fd, uint32_t revents, void *userdata)
  56 {
  57         can_signal_t* sig= (can_signal_t*)userdata;
  58         sig->read_socket();
  59
  60         /* check if error or hangup */
  61         if ((revents & (EPOLLERR|EPOLLRDHUP|EPOLLHUP)) != 0)
  62         {
  63                 sd_event_source_unref(s);
  64                 sig->get_socket().close();
  65                 sig->create_rx_filter();
  66         }
  67         return 0;
  68 }
  69
  70 ///******************************************************************************
  71 ///
  72 ///             Subscription and unsubscription
  73 ///
  74 ///*******************************************************************************/
  75
  76 static int make_subscription_unsubscription(struct afb_req request, const std::string& sig_name, std::map<std::string, struct afb_event>& s, bool subscribe)
  77 {
  78         /* Make the subscription or unsubscription to the event */
  79         if (((subscribe ? afb_req_subscribe : afb_req_unsubscribe)(request, s[sig_name])) < 0)
  80         {
  81                 ERROR(binder_interface, "%s: Operation goes wrong for signal: %s", __FUNCTION__, sig_name.c_str());
  82                 return 0;
  83         }
  84         return 1;
  85 }
  86
  87 static int create_event_handle(const std::string& sig_name, std::map<std::string, struct afb_event>& s)
  88 {
  89         s[sig_name] = afb_daemon_make_event(binder_interface->daemon, sig_name.c_str());
  90         if (!afb_event_is_valid(s[sig_name]))
  91         {
  92                 ERROR(binder_interface, "%s: Can't create an event for %s, something goes wrong.", __FUNCTION__, sig_name.c_str());
  93                 return 0;
  94         }
  95         return 1;
  96 }
  97
  98 /// @brief Will determine if it is needed or not to create the event handle and checks it to be sure that
  99 /// we got a valid afb_event to get subscribe or unsubscribe. Then launch the subscription or unsubscription
 100 /// against the application framework using that event handle.
 101 static int subscribe_unsubscribe_signal(struct afb_req request, bool subscribe, const std::string& sig)
 102 {
 103         int ret;
 104
 105         utils::signals_manager_t& sm = utils::signals_manager_t::instance();
 106
 107         std::lock_guard<std::mutex> subscribed_signals_lock(sm.get_subscribed_signals_mutex());
 108         std::map<std::string, struct afb_event>& s = sm.get_subscribed_signals();
 109         if (s.find(sig) != s.end())
 110         {
 111                 if (!afb_event_is_valid(s[sig]) && !subscribe)
 112                 {
 113                         NOTICE(binder_interface, "%s: Event isn't valid, no need to unsubscribed.", __FUNCTION__);
 114                         ret = -1;
 115                 }
 116                 else
 117                 {
 118                         // Event it isn't valid annymore, recreate it
 119                         ret = create_event_handle(sig, s);
 120                 }
 121         }
 122         else
 123         {
 124                 /* Event doesn't exist , so let's create it */
 125                 struct afb_event empty_event = {nullptr, nullptr};
 126                 s[sig] = empty_event;
 127                 ret = create_event_handle(sig, s);
 128         }
 129
 130         // Check whether or not the event handler has been correctly created and
 131         // make the subscription/unsubscription operation is so.
 132         if (ret <= 0)
 133                 return ret;
 134         return make_subscription_unsubscription(request, sig, s, subscribe);
 135 }
 136
 137 ///
 138 /// @brief subscribe to all signals in the vector signals
 139 ///
 140 /// @param[in] afb_req request : contain original request use to subscribe or unsubscribe
 141 /// @param[in] subscribe boolean value used to chose between a subscription operation or an unsubscription
 142 /// @param[in] signals -  struct containing vectors with can_signal_t and diagnostic_messages to subscribe
 143 ///
 144 /// @return Number of correctly subscribed signal
 145 ///
 146 static int subscribe_unsubscribe_signals(struct afb_req request, bool subscribe, const struct utils::signals_found& signals)
 147 {
 148         int ret,  rets = 0;
 149
 150         //TODO: Implement way to dynamically call the right function no matter
 151         // how much signals types we have.
 152         configuration_t& conf = configuration_t::instance();
 153
 154         for(const auto& sig : signals.diagnostic_messages)
 155         {
 156                 diagnostic_manager_t& diag_m = conf.get_diagnostic_manager();
 157                 DiagnosticRequest* diag_req = conf.get_request_from_diagnostic_message(sig->get_name());
 158
 159                 // If the requested diagnostic message isn't supported by the car then unsubcribe it
 160                 // no matter what we want, worse case will be a fail unsubscription but at least we don't
 161                 // poll a PID for nothing.
 162                 if(sig->get_supported() && subscribe)
 163                 {
 164                                 float frequency = sig->get_frequency();
 165                                 subscribe = diag_m.add_recurring_request(
 166                                         diag_req, sig->get_name().c_str(), false, sig->get_decoder(), sig->get_callback(), (float)frequency);
 167                                         //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);
 168                 }
 169                 else
 170                 {
 171                         diag_m.cleanup_request(
 172                                 diag_m.find_recurring_request(diag_req), true);
 173                         WARNING(binder_interface, "%s: signal: %s isn't supported. Canceling operation.", __FUNCTION__, sig->get_name().c_str());
 174                         return -1;
 175                 }
 176
 177                 ret = subscribe_unsubscribe_signal(request, subscribe, sig->get_name());
 178                 if(ret <= 0)
 179                         return ret;
 180                 rets++;
 181                 DEBUG(binder_interface, "%s: Signal: %s subscribed", __FUNCTION__, sig->get_name().c_str());
 182         }
 183
 184         for(const auto& sig: signals.can_signals)
 185         {
 186                 if(sig->create_rx_filter() <= 0 &&
 187                         subscribe_unsubscribe_signal(request, subscribe, sig->get_name()) <=0)
 188                 {
 189                         return -1;
 190                 }
 191                 struct sd_event_source* e_source;
 192                 sd_event_add_io(afb_daemon_get_event_loop(binder_interface->daemon), &e_source, sig->get_socket().socket(), EPOLLIN, read, sig.get());
 193                 rets++;
 194                 DEBUG(binder_interface, "%s: signal: %s subscribed", __FUNCTION__, sig->get_name().c_str());
 195         }
 196         return rets;
 197 }
 198
 199 static int process_args(struct afb_req request, std::vector<std::string> args, bool subscribe)
 200 {
 201         struct utils::signals_found sf;
 202         int ok = 0, total = 0;
 203
 204         for(const auto& sig: args)
 205         {
 206                 openxc_DynamicField search_key = build_DynamicField(sig);
 207                 sf = utils::signals_manager_t::instance().find_signals(search_key);
 208                 total = (int)sf.can_signals.size() + (int)sf.diagnostic_messages.size();
 209
 210                 if (sf.can_signals.empty() && sf.diagnostic_messages.empty())
 211                         NOTICE(binder_interface, "%s: No signal(s) found for %s.", __FUNCTION__, sig.c_str());
 212                 else
 213                         ok = subscribe_unsubscribe_signals(request, subscribe, sf);
 214         }
 215         NOTICE(binder_interface, "%s: Subscribed/unsubscribe correctly to %d/%d signal(s).", __FUNCTION__, ok, total);
 216         return ok;
 217 }
 218
 219 static const std::vector<std::string> parse_args_from_request(struct afb_req request, bool subscribe)
 220 {
 221         int i, n;
 222         std::vector<std::string> ret;
 223         struct json_object *args, *a, *x;
 224
 225         /* retrieve signals to subscribe */
 226         args = afb_req_json(request);
 227         if (args == NULL || !json_object_object_get_ex(args, "event", &a))
 228         {
 229                 ret.push_back("*");
 230         }
 231         else if (json_object_get_type(a) != json_type_array)
 232         {
 233                 ret.push_back(json_object_get_string(a));
 234         }
 235         else
 236         {
 237                 n = json_object_array_length(a);
 238                 for (i = 0 ; i < n ; i++)
 239                 {
 240                         x = json_object_array_get_idx(a, i);
 241                         ret.push_back(json_object_get_string(x));
 242                 }
 243         }
 244
 245         return ret;
 246 }
 247
 248 void subscribe(struct afb_req request)
 249 {
 250         std::vector<std::string> args;
 251         bool subscribe = true;
 252
 253         args = parse_args_from_request(request, subscribe);
 254
 255         if (process_args(request, args, subscribe) > 0)
 256                 afb_req_success(request, NULL, NULL);
 257         else
 258                 afb_req_fail(request, "error", NULL);
 259 }
 260
 261 void unsubscribe(struct afb_req request)
 262 {
 263         std::vector<std::string> args;
 264         bool subscribe = false;
 265
 266         args = parse_args_from_request(request, subscribe);
 267
 268         if (process_args(request, args, subscribe) > 0)
 269                 afb_req_success(request, NULL, NULL);
 270         else
 271                 afb_req_fail(request, "error", NULL);
 272 }