2 * Copyright (C) 2015, 2016 "IoT.bzh"
3 * Author "Romain Forlot" <romain.forlot@iot.bzh>
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
9 * http://www.apache.org/licenses/LICENSE-2.0
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
19 #include <sys/types.h>
20 #include <sys/socket.h>
21 #include <sys/ioctl.h>
23 #include <linux/can.h>
24 #include <linux/can/raw.h>
26 #include <systemd/sd-event.h>
35 #include <json-c/json.h>
36 #include <openxc.pb.h>
38 #include <afb/afb-binding.h>
39 #include <afb/afb-service-itf.h>
41 #include "ll-can-binding.h"
44 /*************************************************************************/
45 /*************************************************************************/
48 /** SECTION: UTILITY FUNCTIONS **/
51 /*************************************************************************/
52 /*************************************************************************/
55 * Browse chained list and return the one with specified id
57 * param uint32_t id : can arbitration identifier
61 static can_event *get_event_list_of_id(uint32_t id)
65 /* create and return if lists not exists */
68 can_events_list = (can_event*)calloc(1, sizeof(can_event));
69 can_events_list->id = id;
70 return can_events_list;
74 current = can_events_list;
77 if (current->id == id)
81 current->next = (can_event*)calloc(1, sizeof(can_event));
82 current->next->id = id;
85 current = current->next;
92 * Take an id and return it into a char array
94 static char* create_name(uint32_t id)
99 nchar = (size_t)sprintf(name, "can_%u", id);
102 char *result = (char*)malloc(nchar + 1);
103 memcpy(result, name, nchar);
112 * Create json object that will be pushed through event_loop to any subscriber
114 * param : openxc_CanMessage structure complete with data to put into json
117 * return : json object
119 static json_object* create_json_from_openxc_CanMessage(event *event)
121 struct json_object *json;
124 * TODO: process the openxc_CanMessage struct. Should be a call to a
125 * decoder function relative to that msg
127 openxc_CanMessage can_message;
128 can_message = event->can_message;
131 json = json_object_new_object();
132 json_object_object_add(json, "name", json_object_new_string(event->name));
137 /*************************************************************************/
138 /*************************************************************************/
141 /** SECTION: HANDLE CAN DEVICE **/
144 /*************************************************************************/
145 /*************************************************************************/
148 * open the can socket
152 const int canfd_on = 1;
154 struct timeval timeout = {1, 0};
156 DEBUG(interface, "open_can_dev: CAN Handler socket : %d", socket);
160 socket = socket(PF_CAN, SOCK_RAW, CAN_RAW);
163 ERROR(interface, "open_can_dev: socket could not be created");
167 /* Set timeout for read */
168 setsockopt(socket, SOL_SOCKET, SO_RCVTIMEO, (char *)&timeout, sizeof(timeout));
169 /* try to switch the socket into CAN_FD mode */
170 if (setsockopt(socket, SOL_CAN_RAW, CAN_RAW_FD_FRAMES, &canfd_on, sizeof(canfd_on)) < 0)
172 NOTICE(interface, "open_can_dev: Can not switch into CAN Extended frame format.");
173 is_fdmode_on = false;
178 /* Attempts to open a socket to CAN bus */
179 strcpy(ifr.ifr_name, device);
180 if(ioctl(socket, SIOCGIFINDEX, &ifr) < 0)
181 ERROR(interface, "open_can_dev: ioctl failed");
184 txAddress.can_family = AF_CAN;
185 txAddress.can_ifindex = ifr.ifr_ifindex;
187 /* And bind it to txAddress */
188 if (bind(socket, (struct sockaddr *)&txAddress, sizeof(txAddress)) < 0)
190 ERROR(interface, "open_can_dev: bind failed");
194 fcntl(socket, F_SETFL, O_NONBLOCK);
205 * TODO : test that socket is really opened
207 static int write_can()
216 * TODO change old hvac write can frame to generic on_event
218 nbytes = sendto(socket, &canfd_frame, sizeof(struct canfd_frame), 0,
219 (struct sockaddr*)&txAddress, sizeof(txAddress));
222 ERROR(interface, "write_can: Sending CAN frame failed.");
227 ERROR(interface, "write_can: socket not initialized. Attempt to reopen can device socket.");
234 * Parse the CAN frame data payload as a CAN packet
235 * TODO: parse as an OpenXC Can Message. Don't translate as ASCII and put bytes
236 * directly into openxc_CanMessage
238 static int parse_can_frame(openxc_CanMessage *can_message, struct canfd_frame *canfd_frame, int maxdlen)
243 len = (canfd_frame->len > maxdlen) ? maxdlen : canfd_frame->len;
245 can_message->has_id = true;
246 if (canfd_frame->can_id & CAN_ERR_FLAG)
247 can_message->id = canfd_frame->can_id & (CAN_ERR_MASK|CAN_ERR_FLAG);
248 else if (canfd_frame->can_id & CAN_EFF_FLAG)
250 can_message->has_frame_format = true;
251 can_message->frame_format = openxc_CanMessage_FrameFormat_EXTENDED;
252 can_message->id = canfd_frame->can_id & CAN_EFF_MASK;
255 can_message->has_frame_format = true;
256 can_message->frame_format = openxc_CanMessage_FrameFormat_STANDARD;
257 can_message->id = canfd_frame->can_id & CAN_SFF_MASK;
260 /* Don't know what to do with that for now as we haven't
261 * len fields in openxc_CanMessage struct
263 * standard CAN frames may have RTR enabled. There are no ERR frames with RTR
264 if (maxdlen == CAN_MAX_DLEN && canfd_frame->can_id & CAN_RTR_FLAG)
266 // print a given CAN 2.0B DLC if it's not zero
267 if (canfd_frame->len && canfd_frame->len <= CAN_MAX_DLC)
268 buf[offset++] = hex_asc_upper[canfd_frame->len & 0xF];
275 /* Doesn't handle real canfd_frame for now
276 if (maxdlen == CANFD_MAX_DLEN)
278 // add CAN FD specific escape char and flags
279 canfd_frame->flags & 0xF;
282 if (sizeof(canfd_frame->data) <= sizeof(can_message->data.bytes))
284 for (i = 0; i < len; i++)
285 can_message->data.bytes[i] = canfd_frame->data[i];
287 } else if (sizeof(canfd_frame->data) <= CAN_MAX_DLEN)
289 ERROR(interface, "parse_can_frame: can_frame data too long to be stored into openxc_CanMessage data field");
291 /* TODO create as many as needed openxc_CanMessage into an array to store all data from canfd_frame
292 n_msg = CAN_MAX_DLEN / sizeof(canfd_frame->data.bytes);
293 for (i = 0; i < len; i++)
294 can_message->data.bytes[i] = canfd_frame->data[i]; */
297 ERROR(interface, "parse_can_frame: can_frame is really too long here. Size of data greater than canfd maximum 64bytes size. Is it a CAN message ?");
301 /* You should not reach this return statement */
307 * Read on CAN bus and return how much bytes has been read.
309 static int read_can(openxc_CanMessage *can_message)
314 /* Test that socket is really opened */
315 if ( socket_test() < 0)
317 if (open_can_dev() < 0)
319 ERROR(interface, "read_can: Socket unavailable");
324 nbytes = read(socket, &canfd_frame, CANFD_MTU);
326 if (nbytes == CANFD_MTU)
328 DEBUG(interface, "read_can: Got an CAN FD frame with length %d", canfd_frame.len);
330 else if (nbytes == CAN_MTU)
332 DEBUG(interface, "read_can: Got a legacy CAN frame with length %d", canfd_frame.len);
336 if (errno == ENETDOWN)
337 ERROR(interface, "read_can: %s interface down", device);
338 ERROR(interface, "read_can: Error reading CAN bus");
342 /* CAN frame integrity check */
343 if ((size_t)nbytes == CAN_MTU)
344 maxdlen = CAN_MAX_DLEN;
345 else if ((size_t)nbytes == CANFD_MTU)
346 maxdlen = CANFD_MAX_DLEN;
349 ERROR(interface, "read_can: CAN frame incomplete");
353 if (parse_can_frame(can_message, &canfd_frame, maxdlen))
355 ERROR(interface, "read_can: Can't parse the can frame. ID: %i, DLC: %i, DATA: %s",
356 canfd_frame.can_id, canfd_frame.len, canfd_frame.data);
362 /*************************************************************************/
363 /*************************************************************************/
366 /** SECTION: MANAGING EVENTS **/
369 /*************************************************************************/
370 /*************************************************************************/
371 static int on_event(sd_event_source *s, int fd, uint32_t revents, void *userdata);
374 * Get the event loop running.
375 * Will trigger on_event function on EPOLLIN event on socket
377 * Return 0 or positive value on success. Else negative value for failure.
379 static int connect_to_event_loop(CanBus &CanBus_handler)
381 sd_event *event_loop;
382 sd_event_source *source;
385 if (CanBus_handler.socket < 0)
387 return CanBus_handler.socket;
390 event_loop = afb_daemon_get_event_loop(interface->daemon);
391 rc = sd_event_add_io(event_loop, &source, CanBus_handler.socket, EPOLLIN, on_event, NULL);
394 CanBus_handler.close();
395 ERROR(interface, "Can't connect CAN bus %s to the event loop", CanBus_handler.device);
398 NOTICE(interface, "Connected CAN bus %s to the event loop", CanBus_handler.device);
406 static void send_event()
412 /* Browse can_events */
413 current = can_events_list;
416 /* Browse event for each can_events no matter what the id */
417 events = current->events;
420 object = create_json_from_openxc_CanMessage(events);
421 afb_event_push(events->afb_event, object);
422 events = events->next;
424 current = current->next;
429 * called on an event on the CAN bus
431 static int on_event(sd_event_source *s, int fd, uint32_t revents, void *userdata)
433 openxc_CanMessage can_message;
435 can_message = openxc_CanMessage_init_default;
437 /* read available data */
438 if ((revents & EPOLLIN) != 0)
440 read_can(&can_message);
444 /* check if error or hangup */
445 if ((revents & (EPOLLERR|EPOLLRDHUP|EPOLLHUP)) != 0)
447 sd_event_source_unref(s);
449 connect_to_event_loop();
456 * get or create an event handler for the type
458 static event *get_event(uint32_t id, enum type type)
463 /* find the can list by id */
464 list = get_event_list_of_id(id);
466 /* make the new event */
467 event_elt = (event*)calloc(1, sizeof(event));
468 event_elt->next = event_elt;
469 list->events = event_elt;
470 event_elt->name = create_name(id);
471 event_elt->afb_event = afb_daemon_make_event(interface->daemon, event_elt->name);
476 /*************************************************************************/
477 /*************************************************************************/
480 /** SECTION: BINDING VERBS IMPLEMENTATION **/
483 /*************************************************************************/
484 /*************************************************************************/
486 * Returns the type corresponding to the given name
488 static enum type type_of_name(const char *name)
493 for (result = 0 ; (size_t)result < type_size; result++)
494 if (strcmp(type_NAMES[result], name) == 0)
500 * extract a valid type from the request
502 static int get_type_for_req(struct afb_req req, enum type *type)
504 if ((*type = type_of_name(afb_req_value(req, "type"))) != type_INVALID)
506 afb_req_fail(req, "unknown-type", NULL);
510 static int subscribe_unsubscribe_sig(struct afb_req request, int subscribe, struct signal *sig)
512 if (!afb_event_is_valid(sig->event)) {
515 sig->event = afb_daemon_make_event(afbitf->daemon, sig->name);
516 if (!afb_event_is_valid(sig->event)) {
521 if (((subscribe ? afb_req_subscribe : afb_req_unsubscribe)(request, sig->event)) < 0) {
528 static int subscribe_unsubscribe_all(struct afb_req request, int subscribe)
532 n = sizeof OBD2_PIDS / sizeof * OBD2_PIDS;
534 for (i = 0 ; i < n ; i++)
535 e += !subscribe_unsubscribe_sig(request, subscribe, &OBD2_PIDS[i]);
539 static int subscribe_unsubscribe_name(struct afb_req request, int subscribe, const char *name)
543 if (0 == strcmp(name, "*"))
544 return subscribe_unsubscribe_all(request, subscribe);
551 return subscribe_unsubscribe_sig(request, subscribe, sig);
554 static void subscribe_unsubscribe(struct afb_req request, int subscribe)
557 struct json_object *args, *a, *x;
559 /* makes the subscription/unsubscription */
560 args = afb_req_json(request);
561 if (args == NULL || !json_object_object_get_ex(args, "event", &a)) {
562 ok = subscribe_unsubscribe_all(request, subscribe);
563 } else if (json_object_get_type(a) != json_type_array) {
564 ok = subscribe_unsubscribe_name(request, subscribe, json_object_get_string(a));
566 n = json_object_array_length(a);
568 for (i = 0 ; i < n ; i++) {
569 x = json_object_array_get_idx(a, i);
570 if (subscribe_unsubscribe_name(request, subscribe, json_object_get_string(x)))
576 /* send the report */
578 afb_req_success(request, NULL, NULL);
580 afb_req_fail(request, "error", NULL);
583 static void subscribe(struct afb_req request)
585 subscribe_unsubscribe(request, 1);
588 static void unsubscribe(struct afb_req request)
590 subscribe_unsubscribe(request, 0);
593 static const struct afb_verb_desc_v1 verbs[]=
595 { .name= "subscribe", .session= AFB_SESSION_NONE, .callback= subscribe, .info= "subscribe to notification of CAN bus messages." },
596 { .name= "unsubscribe", .session= AFB_SESSION_NONE, .callback= unsubscribe, .info= "unsubscribe a previous subscription." },
600 static const struct afb_binding binding_desc = {
601 .type = AFB_BINDING_VERSION_1,
603 .info = "CAN bus service",
609 const struct afb_binding *afbBindingV1Register (const struct afb_binding_interface *itf)
613 return &binding_desc;
616 int afbBindingV1ServiceInit(struct afb_service service)
618 /* Open JSON conf file */
620 /* Open CAN socket */
621 CanBus_handler.open();
623 return connect_to_event_loop(CanBus_handler);