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 "application.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 #include "canutil/write.h"
  39
  40 extern "C"
  41 {
  42         #include <afb/afb-service-itf.h>
  43 };
  44
  45 ///******************************************************************************
  46 ///
  47 ///     low_can_subscription_t object
  48 ///
  49 ///*******************************************************************************/
  50
  51 low_can_subscription_t::low_can_subscription_t()
  52         : index_{-1},
  53         event_filter_{event_filter_t()},
  54         socket_{}
  55 {}
  56
  57 low_can_subscription_t::low_can_subscription_t(struct event_filter_t event_filter)
  58         : event_filter_{event_filter}
  59 {}
  60
  61 low_can_subscription_t::low_can_subscription_t( low_can_subscription_t&& s)
  62         : index_{s.index_},
  63         event_filter_{s.event_filter_},
  64         socket_{std::move(s.socket_)}
  65 {}
  66
  67         low_can_subscription_t& low_can_subscription_t::operator=(const low_can_subscription_t& s)
  68 {
  69         socket_ = std::move(s.socket_);
  70         return *this;
  71 }
  72
  73 low_can_subscription_t::~low_can_subscription_t()
  74 {
  75         socket_.close();
  76 }
  77
  78 low_can_subscription_t::operator bool() const
  79 {
  80         return ((can_signal_ != nullptr || ! diagnostic_message_.empty()) && afb_event_is_valid(event_));
  81 }
  82
  83 struct afb_event& low_can_subscription_t::get_event()
  84 {
  85         return event_;
  86 }
  87
  88 int low_can_subscription_t::get_index() const
  89 {
  90         return index_;
  91 }
  92
  93 const std::shared_ptr<can_signal_t> low_can_subscription_t::get_can_signal() const
  94 {
  95         return can_signal_;
  96 }
  97
  98 const std::vector<std::shared_ptr<diagnostic_message_t> > low_can_subscription_t::get_diagnostic_message() const
  99 {
 100         return diagnostic_message_;
 101 }
 102
 103 const std::shared_ptr<diagnostic_message_t> low_can_subscription_t::get_diagnostic_message(uint32_t pid) const
 104 {
 105         for(const auto& diag: diagnostic_message_)
 106         {
 107                 if(diag->get_pid() == pid)
 108                 {
 109                         return diag;
 110                 }
 111         }
 112         return nullptr;
 113 }
 114
 115 const std::shared_ptr<diagnostic_message_t> low_can_subscription_t::get_diagnostic_message(const std::string& name) const
 116 {
 117         for(const auto& diag: diagnostic_message_)
 118         {
 119                 if(diag->get_name() == name)
 120                 {
 121                         return diag;
 122                 }
 123         }
 124         return nullptr;
 125 }
 126
 127 const std::string low_can_subscription_t::get_name() const
 128 {
 129         if (can_signal_ != nullptr)
 130                 return can_signal_->get_name();
 131
 132         return "";
 133 }
 134
 135 const std::string low_can_subscription_t::get_name(uint32_t pid) const
 136 {
 137         if (!diagnostic_message_.empty())
 138                 return get_diagnostic_message(pid)->get_name() ;
 139
 140         return "";
 141 }
 142
 143 float low_can_subscription_t::get_frequency() const
 144 {
 145         return event_filter_.frequency;
 146 }
 147
 148 float low_can_subscription_t::get_min() const
 149 {
 150         return event_filter_.min;
 151 }
 152
 153 float low_can_subscription_t::get_max() const
 154 {
 155         return event_filter_.max;
 156 }
 157
 158 utils::socketcan_bcm_t& low_can_subscription_t::get_socket()
 159 {
 160         return socket_;
 161 }
 162
 163 void low_can_subscription_t::set_event(struct afb_event event)
 164 {
 165         event_ = event;
 166 }
 167
 168 void low_can_subscription_t::set_frequency(float freq)
 169 {
 170         event_filter_.frequency = freq;
 171 }
 172
 173 void low_can_subscription_t::set_min(float min)
 174 {
 175         event_filter_.min = min;
 176 }
 177
 178 void low_can_subscription_t::set_max(float max)
 179 {
 180         event_filter_.max = max;
 181 }
 182
 183 int low_can_subscription_t::open_socket()
 184 {
 185         int ret = 0;
 186         if(! socket_)
 187         {
 188                 if( can_signal_ != nullptr)
 189                         {ret = socket_.open(can_signal_->get_message()->get_bus_device_name());}
 190                 else if (! diagnostic_message_ .empty())
 191                         {ret = socket_.open(application_t::instance().get_diagnostic_manager().get_bus_device_name());}
 192                 index_ = (int)socket_.socket();
 193         }
 194         return ret;
 195 }
 196
 197 struct utils::simple_bcm_msg low_can_subscription_t::make_bcm_head(uint32_t can_id, uint32_t flags, const struct timeval& timeout, const struct timeval& frequency_thinning) const
 198 {
 199         struct utils::simple_bcm_msg bcm_msg;
 200
 201         memset(&bcm_msg, 0, sizeof(bcm_msg));
 202
 203         bcm_msg.msg_head.opcode  = RX_SETUP;
 204         bcm_msg.msg_head.can_id  = can_id;
 205         bcm_msg.msg_head.flags = flags;
 206         bcm_msg.msg_head.ival1.tv_sec = timeout.tv_sec ;
 207         bcm_msg.msg_head.ival1.tv_usec = timeout.tv_usec;
 208         bcm_msg.msg_head.ival2.tv_sec = frequency_thinning.tv_sec ;
 209         bcm_msg.msg_head.ival2.tv_usec = frequency_thinning.tv_usec;
 210
 211         return bcm_msg;
 212 }
 213
 214 void low_can_subscription_t::add_bcm_frame(const struct can_frame& cfd, struct utils::simple_bcm_msg& bcm_msg) const
 215 {
 216         for(int i=0; i < CAN_MAX_DLEN; i++)
 217         {
 218                 if(cfd.data[i] != 0)
 219                 {
 220                         bcm_msg.msg_head.nframes = 1;
 221                         bcm_msg.frames = cfd;
 222                         return;
 223                 }
 224         }
 225 }
 226
 227 /// @brief Create a RX_SETUP receive job used by the BCM socket.
 228 ///
 229 /// @return 0 if ok else -1
 230 int low_can_subscription_t::create_rx_filter()
 231 {
 232         int ret = -1;
 233         if ( can_signal_ != nullptr)
 234                 {ret = create_rx_filter(can_signal_);}
 235         else if (! diagnostic_message_ .empty())
 236                 {ret = create_rx_filter(diagnostic_message_.front());}
 237
 238         return ret;
 239 }
 240
 241 /// @brief Create a RX_SETUP receive job used by the BCM socket.
 242 ///
 243 /// @return 0 if ok else -1
 244 int low_can_subscription_t::create_rx_filter(std::shared_ptr<can_signal_t> sig)
 245 {
 246         can_signal_= sig;
 247
 248         struct can_frame cfd;
 249         memset(&cfd, 0, sizeof(cfd));
 250
 251         float val = (float)(1 << can_signal_->get_bit_size()) - 1;
 252         bitfield_encode_float(val,
 253                                                         can_signal_->get_bit_position(),
 254                                                         can_signal_->get_bit_size(),
 255                                                         can_signal_->get_factor(),
 256                                                         can_signal_->get_offset(),
 257                                                         cfd.data,
 258                                                         CAN_MAX_DLEN);
 259
 260         struct timeval freq, timeout = {0, 0};
 261         frequency_clock_t f = std::isnan(event_filter_.frequency) ? can_signal_->get_frequency() : frequency_clock_t(event_filter_.frequency);
 262         freq = f.get_timeval_from_period();
 263
 264         utils::simple_bcm_msg bcm_msg = make_bcm_head(can_signal_->get_message()->get_id(), SETTIMER|RX_NO_AUTOTIMER, timeout, freq);
 265         add_bcm_frame(cfd, bcm_msg);
 266
 267         return create_rx_filter(bcm_msg);
 268 }
 269
 270 /// @brief Create a RX_SETUP receive job used by the BCM socket.
 271 ///
 272 /// @return 0 if ok else -1
 273 int low_can_subscription_t::create_rx_filter(std::shared_ptr<diagnostic_message_t> sig)
 274 {
 275         diagnostic_message_.push_back(sig);
 276
 277         struct timeval freq = frequency_clock_t(event_filter_.frequency).get_timeval_from_period();
 278         //struct timeval timeout = frequency_clock_t(10).get_timeval_from_period();
 279         struct timeval timeout = {0,0};
 280
 281         utils::simple_bcm_msg bcm_msg =  make_bcm_head(OBD2_FUNCTIONAL_BROADCAST_ID, SETTIMER|RX_NO_AUTOTIMER|RX_FILTER_ID, timeout, freq);
 282         return create_rx_filter(bcm_msg);
 283 }
 284
 285 /// @brief Create a RX_SETUP receive job used by the BCM socket.
 286 ///
 287 /// @return 0 if ok else -1
 288 int low_can_subscription_t::create_rx_filter(utils::simple_bcm_msg& bcm_msg)
 289 {
 290         // Make sure that socket has been opened.
 291         if(open_socket() < 0)
 292                 {return -1;}
 293
 294         // If it isn't an OBD2 CAN ID then just add a simple RX_SETUP job
 295         // else monitor all standard 8 CAN OBD2 ID response.
 296         if(bcm_msg.msg_head.can_id != OBD2_FUNCTIONAL_BROADCAST_ID)
 297         {
 298                 socket_ << bcm_msg;
 299                         if(! socket_)
 300                                 return -1;
 301         }
 302         else
 303         {
 304                 for(uint8_t i = 0; i < 8; i++)
 305                 {
 306                         bcm_msg.msg_head.can_id  =  OBD2_FUNCTIONAL_RESPONSE_START + i;
 307
 308                         socket_ << bcm_msg;
 309                         if(! socket_)
 310                                 return -1;
 311                 }
 312         }
 313
 314         return 0;
 315 }
 316
 317 ///******************************************************************************
 318 ///
 319 ///             SystemD event loop Callbacks
 320 ///
 321 ///*******************************************************************************/
 322
 323 void on_no_clients(std::shared_ptr<low_can_subscription_t> can_subscription, uint32_t pid)
 324 {
 325         if( ! can_subscription->get_diagnostic_message().empty() && can_subscription->get_diagnostic_message(pid) != nullptr)
 326         {
 327                 DiagnosticRequest diag_req = can_subscription->get_diagnostic_message(pid)->build_diagnostic_request();
 328                 active_diagnostic_request_t* adr = application_t::instance().get_diagnostic_manager().find_recurring_request(diag_req);
 329                 if( adr != nullptr)
 330                         application_t::instance().get_diagnostic_manager().cleanup_request(adr, true);
 331         }
 332
 333         on_no_clients(can_subscription);
 334 }
 335
 336 void on_no_clients(std::shared_ptr<low_can_subscription_t> can_subscription)
 337 {
 338         utils::signals_manager_t& sm = utils::signals_manager_t::instance();
 339         std::lock_guard<std::mutex> subscribed_signals_lock(sm.get_subscribed_signals_mutex());
 340         std::map<int, std::shared_ptr<low_can_subscription_t> >& s = sm.get_subscribed_signals();
 341         auto it = s.find(can_subscription->get_index());
 342         s.erase(it);
 343 }
 344
 345 static void push_n_notify(const can_message_t& cm)
 346 {
 347         can_bus_t& cbm = application_t::instance().get_can_bus_manager();
 348         {
 349                 std::lock_guard<std::mutex> can_message_lock(cbm.get_can_message_mutex());
 350                 cbm.push_new_can_message(cm);
 351         }
 352         cbm.get_new_can_message_cv().notify_one();
 353 }
 354
 355 int read_message(sd_event_source *event_source, int fd, uint32_t revents, void *userdata)
 356 {
 357         low_can_subscription_t* can_subscription = (low_can_subscription_t*)userdata;
 358         if ((revents & EPOLLIN) != 0)
 359         {
 360                 can_message_t cm;
 361                 utils::socketcan_bcm_t& s = can_subscription->get_socket();
 362                 s >> cm;
 363
 364                 push_n_notify(cm);
 365         }
 366
 367         /* check if error or hangup */
 368         if ((revents & (EPOLLERR|EPOLLRDHUP|EPOLLHUP)) != 0)
 369         {
 370                 sd_event_source_unref(event_source);
 371                 can_subscription->get_socket().close();
 372         }
 373         return 0;
 374 }
 375
 376 ///******************************************************************************
 377 ///
 378 ///             Subscription and unsubscription
 379 ///
 380 ///*******************************************************************************/
 381
 382 static int make_subscription_unsubscription(struct afb_req request, std::shared_ptr<low_can_subscription_t>& can_subscription, std::map<int, std::shared_ptr<low_can_subscription_t> >& s, bool subscribe)
 383 {
 384         /* Make the subscription or unsubscription to the event */
 385         if (((subscribe ? afb_req_subscribe : afb_req_unsubscribe)(request, s[can_subscription->get_index()]->get_event())) < 0)
 386         {
 387                 ERROR(binder_interface, "%s: Operation goes wrong for signal: %s", __FUNCTION__, can_subscription->get_name().c_str());
 388                 return -1;
 389         }
 390         return 0;
 391 }
 392
 393 static int create_event_handle(std::shared_ptr<low_can_subscription_t>& can_subscription, std::map<int, std::shared_ptr<low_can_subscription_t> >& s)
 394 {
 395         int sub_index = can_subscription->get_index();
 396         can_subscription->set_event(afb_daemon_make_event(binder_interface->daemon, can_subscription->get_name().c_str()));
 397         s[sub_index] = can_subscription;
 398         if (!afb_event_is_valid(s[sub_index]->get_event()))
 399         {
 400                 ERROR(binder_interface, "%s: Can't create an event for %s, something goes wrong.", __FUNCTION__, can_subscription->get_name().c_str());
 401                 return -1;
 402         }
 403         return 0;
 404 }
 405
 406 /// @brief Will determine if it is needed or not to create the event handle and checks it to be sure that
 407 /// we got a valid afb_event to get subscribe or unsubscribe. Then launch the subscription or unsubscription
 408 /// against the application framework using that event handle.
 409 static int subscribe_unsubscribe_signal(struct afb_req request, bool subscribe, std::shared_ptr<low_can_subscription_t>& can_subscription, std::map<int, std::shared_ptr<low_can_subscription_t> >& s)
 410 {
 411         int ret;
 412         int sub_index = can_subscription->get_index();
 413
 414         if (can_subscription && s.find(sub_index) != s.end())
 415         {
 416                 if (!afb_event_is_valid(s[sub_index]->get_event()) && !subscribe)
 417                 {
 418                         NOTICE(binder_interface, "%s: Event isn't valid, no need to unsubscribed.", __FUNCTION__);
 419                         ret = -1;
 420                 }
 421         }
 422         else
 423         {
 424                 /* Event doesn't exist , so let's create it */
 425                 can_subscription->set_event({nullptr, nullptr});
 426                 s[sub_index] = can_subscription;
 427                 ret = create_event_handle(can_subscription, s);
 428         }
 429
 430         // Check whether or not the event handler has been correctly created and
 431         // make the subscription/unsubscription operation is so.
 432         if (ret < 0)
 433                 return ret;
 434         return make_subscription_unsubscription(request, can_subscription, s, subscribe);
 435 }
 436
 437 static int add_to_event_loop(std::shared_ptr<low_can_subscription_t>& can_subscription)
 438 {
 439                 struct sd_event_source* event_source = nullptr;
 440                 return ( sd_event_add_io(afb_daemon_get_event_loop(binder_interface->daemon),
 441                         &event_source,
 442                         can_subscription->get_socket().socket(),
 443                         EPOLLIN,
 444                         read_message,
 445                         can_subscription.get()));
 446 }
 447
 448 static int subscribe_unsubscribe_diagnostic_messages(struct afb_req request, bool subscribe, std::vector<std::shared_ptr<diagnostic_message_t> > diagnostic_messages, struct event_filter_t& event_filter, std::map<int, std::shared_ptr<low_can_subscription_t> >& s)
 449 {
 450         int rets = 0;
 451         application_t& app = application_t::instance();
 452         diagnostic_manager_t& diag_m = app.get_diagnostic_manager();
 453
 454         for(const auto& sig : diagnostic_messages)
 455         {
 456                 DiagnosticRequest* diag_req = new DiagnosticRequest(sig->build_diagnostic_request());
 457                 event_filter.frequency = std::isnan(event_filter.frequency) ? sig->get_frequency() : event_filter.frequency;
 458                 std::shared_ptr<low_can_subscription_t> can_subscription;
 459
 460                 auto it =  std::find_if(s.begin(), s.end(), [&sig](std::pair<int, std::shared_ptr<low_can_subscription_t> > sub){ return (! sub.second->get_diagnostic_message().empty());});
 461                 can_subscription = it != s.end() ?
 462                         it->second :
 463                         std::make_shared<low_can_subscription_t>(low_can_subscription_t(event_filter));
 464                 // If the requested diagnostic message isn't supported by the car then unsubcribe it
 465                 // no matter what we want, worse case will be a fail unsubscription but at least we don't
 466                 // poll a PID for nothing.
 467                 //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);
 468                 if(sig->get_supported() && subscribe)
 469                 {
 470                         diag_m.add_recurring_request(diag_req, sig->get_name().c_str(), false, sig->get_decoder(), sig->get_callback(), event_filter.frequency);
 471                         if(can_subscription->create_rx_filter(sig) < 0)
 472                                 {return -1;}
 473                         DEBUG(binder_interface, "%s: Signal: %s subscribed", __FUNCTION__, sig->get_name().c_str());
 474                         if(it == s.end() && add_to_event_loop(can_subscription) < 0)
 475                         {
 476                                 diag_m.cleanup_request(
 477                                         diag_m.find_recurring_request(*diag_req), true);
 478                                 WARNING(binder_interface, "%s: signal: %s isn't supported. Canceling operation.", __FUNCTION__,  sig->get_name().c_str());
 479                                 return -1;
 480                         }
 481                 }
 482                 else
 483                 {
 484                         diag_m.cleanup_request(
 485                                         diag_m.find_recurring_request(*diag_req), true);
 486                         if(sig->get_supported())
 487                         {DEBUG(binder_interface, "%s: %s cancelled due to unsubscribe", __FUNCTION__, sig->get_name().c_str());}
 488                         else
 489                         {
 490                                 WARNING(binder_interface, "%s: signal: %s isn't supported. Canceling operation.", __FUNCTION__, sig->get_name().c_str());
 491                                 return -1;
 492                         }
 493                 }
 494                 int ret = subscribe_unsubscribe_signal(request, subscribe, can_subscription, s);
 495                 if(ret < 0)
 496                         return ret;
 497
 498                 rets++;
 499         }
 500
 501         return rets;
 502 }
 503
 504 static int subscribe_unsubscribe_can_signals(struct afb_req request, bool subscribe, std::vector<std::shared_ptr<can_signal_t> > can_signals, struct event_filter_t& event_filter, std::map<int, std::shared_ptr<low_can_subscription_t> >& s)
 505 {
 506         int rets = 0;
 507         for(const auto& sig: can_signals)
 508         {
 509                 auto it =  std::find_if(s.begin(), s.end(), [&sig](std::pair<int, std::shared_ptr<low_can_subscription_t> > sub){ return sub.second->get_can_signal() == sig; });
 510                 std::shared_ptr<low_can_subscription_t> can_subscription;
 511                 if(it != s.end())
 512                 {
 513                          can_subscription = it->second;
 514                 }
 515                 else
 516                 {
 517                          can_subscription = std::make_shared<low_can_subscription_t>(low_can_subscription_t(event_filter));
 518                         if(can_subscription->create_rx_filter(sig) < 0)
 519                                 {return -1;}
 520                 }
 521
 522                 if(subscribe_unsubscribe_signal(request, subscribe, can_subscription, s) < 0)
 523                         {return -1;}
 524
 525                 if(add_to_event_loop(can_subscription) < 0)
 526                         {return -1;}
 527                 rets++;
 528                 DEBUG(binder_interface, "%s: signal: %s subscribed", __FUNCTION__, sig->get_name().c_str());
 529         }
 530         return rets;
 531 }
 532
 533 ///
 534 /// @brief subscribe to all signals in the vector signals
 535 ///
 536 /// @param[in] afb_req request : contain original request use to subscribe or unsubscribe
 537 /// @param[in] subscribe boolean value used to chose between a subscription operation or an unsubscription
 538 /// @param[in] signals -  struct containing vectors with can_signal_t and diagnostic_messages to subscribe
 539 ///
 540 /// @return Number of correctly subscribed signal
 541 ///
 542 static int subscribe_unsubscribe_signals(struct afb_req request, bool subscribe, const struct utils::signals_found& signals, struct event_filter_t& event_filter)
 543 {
 544         int rets = 0;
 545         utils::signals_manager_t& sm = utils::signals_manager_t::instance();
 546
 547         std::lock_guard<std::mutex> subscribed_signals_lock(sm.get_subscribed_signals_mutex());
 548         std::map<int, std::shared_ptr<low_can_subscription_t> >& s = sm.get_subscribed_signals();
 549
 550         rets += subscribe_unsubscribe_diagnostic_messages(request, subscribe, signals.diagnostic_messages, event_filter, s);
 551         rets += subscribe_unsubscribe_can_signals(request, subscribe, signals.can_signals, event_filter, s);
 552
 553         return rets;
 554 }
 555
 556 static int one_subscribe_unsubscribe(struct afb_req request, bool subscribe, const std::string& tag, json_object* args)
 557 {
 558         int ret = 0;
 559         struct event_filter_t event_filter;
 560         struct json_object  *filter, *obj;
 561         struct utils::signals_found sf;
 562
 563         // computes the filter
 564         if (json_object_object_get_ex(args, "filter", &filter))
 565         {
 566                 if (json_object_object_get_ex(filter, "frequency", &obj)
 567                 && (json_object_is_type(obj, json_type_double) || json_object_is_type(obj, json_type_int)))
 568                 {
 569                         event_filter.frequency = (float)json_object_get_double(obj);
 570                         ret += 1;
 571                 }
 572                 if (json_object_object_get_ex(filter, "min", &obj)
 573                 && (json_object_is_type(obj, json_type_double) || json_object_is_type(obj, json_type_int)))
 574                 {
 575                         event_filter.min = (float)json_object_get_double(obj);
 576                         ret += 2;
 577                 }
 578                 if (json_object_object_get_ex(filter, "max", &obj)
 579                 && (json_object_is_type(obj, json_type_double) || json_object_is_type(obj, json_type_int)))
 580                 {
 581                         event_filter.max = (float)json_object_get_double(obj);
 582                         ret += 4;
 583                 }
 584         }
 585
 586         // subscribe or unsubscribe
 587         openxc_DynamicField search_key = build_DynamicField(tag);
 588         sf = utils::signals_manager_t::instance().find_signals(search_key);
 589         if (sf.can_signals.empty() && sf.diagnostic_messages.empty())
 590                 NOTICE(binder_interface, "%s: No signal(s) found for %s.", __FUNCTION__, tag.c_str());
 591         else
 592                 ret = subscribe_unsubscribe_signals(request, subscribe, sf, event_filter);
 593
 594         return ret;
 595 }
 596
 597 static void do_subscribe_unsubscribe(struct afb_req request, bool subscribe)
 598 {
 599         int i, n, rc, rc2;
 600         struct json_object *args, *event, *x;
 601
 602         args = afb_req_json(request);
 603         if (args == NULL || !json_object_object_get_ex(args, "event", &event))
 604         {
 605                 rc = one_subscribe_unsubscribe(request, subscribe, "*", args);
 606         }
 607         else if (json_object_get_type(event) != json_type_array)
 608         {
 609                 rc = one_subscribe_unsubscribe(request, subscribe, json_object_get_string(event), args);
 610         }
 611         else
 612         {
 613                 rc = 0;
 614                 n = json_object_array_length(event);
 615                 for (i = 0 ; i < n ; i++)
 616                 {
 617                         x = json_object_array_get_idx(event, i);
 618                         rc2 = one_subscribe_unsubscribe(request, subscribe, json_object_get_string(x), args);
 619                         if (rc >= 0)
 620                                 rc = rc2 >= 0 ? rc + rc2 : rc2;
 621                 }
 622         }
 623
 624         if (rc >= 0)
 625                 afb_req_success(request, NULL, NULL);
 626         else
 627                 afb_req_fail(request, "error", NULL);
 628 }
 629
 630 void subscribe(struct afb_req request)
 631 {
 632         do_subscribe_unsubscribe(request, true);
 633 }
 634
 635 void unsubscribe(struct afb_req request)
 636 {
 637         do_subscribe_unsubscribe(request, false);
 638 }