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.
22 #include <sys/types.h>
23 #include <sys/socket.h>
24 #include <sys/ioctl.h>
27 #include <linux/can.h>
28 #include <linux/can/raw.h>
31 #include <systemd/sd-event.h>
34 #include <json-c/json.h>
35 #include <openxc.pb.h>
37 #include <afb/afb-binding.h>
38 #include <afb/afb-service-itf.h>
40 /*****************************************************************************************/
41 /*****************************************************************************************/
44 /** SECTION: GLOBAL VARIABLES **/
47 /*****************************************************************************************/
48 /*****************************************************************************************/
50 /* max. number of CAN interfaces given on the cmdline */
53 /* buffer sizes for CAN frame string representations */
54 #define CL_ID (sizeof("12345678##1"))
55 #define CL_DATA sizeof(".AA")
56 #define CL_BINDATA sizeof(".10101010")
58 /* CAN FD ASCII hex short representation with DATA_SEPERATORs */
59 #define CL_CFSZ (2*CL_ID + 64*CL_DATA)
61 #define CANID_DELIM '#'
64 * the type of position expected
66 * here, this type is the selection of protocol
71 type_DEFAULT = type_CAN,
75 #define type_size sizeof(enum type)-2
78 * each generated event
81 struct event *next; /* link for the same period */
82 const char *name; /* name of the event */
83 struct afb_event event; /* the event for the binder */
84 enum type type; /* the type of data expected */
85 int id; /* id of the event for unsubscribe */
88 /* CAN variable initialization */
90 static __u32 dropcnt[MAXSOCK];
91 static __u32 last_dropcnt[MAXSOCK];
93 struct canfd_frame canfd_frame;
98 openxc_CanMessage *msg;
99 struct sockaddr_can txAddress;
104 /*****************************************************************************************/
105 /*****************************************************************************************/
108 /** SECTION: UTILITY FUNCTIONS **/
111 /*****************************************************************************************/
112 /*****************************************************************************************/
114 * Interface between the daemon and the binding
116 static const struct afb_binding_interface *interface;
119 * @brief Retry a function 3 times
121 * @param int function(): function that return an int wihtout any parameter
123 * @ return : 0 if ok, -1 if failed
126 static int retry( int(*func)());
127 static int retry( int(*func)())
142 /*****************************************************************************************/
143 /*****************************************************************************************/
146 /** SECTION: HANDLE CAN DEVICE **/
149 /*****************************************************************************************/
150 /*****************************************************************************************/
151 const char hex_asc_upper[] = "0123456789ABCDEF";
153 #define hex_asc_upper_lo(x) hex_asc_upper[((x) & 0x0F)]
154 #define hex_asc_upper_hi(x) hex_asc_upper[((x) & 0xF0) >> 4]
156 static inline void _put_id(char *buf, int end_offset, canid_t id)
158 /* build 3 (SFF) or 8 (EFF) digit CAN identifier */
159 while (end_offset >= 0) {
160 buf[end_offset--] = hex_asc_upper[id & 0xF];
165 #define put_sff_id(buf, id) _put_id(buf, 2, id)
166 #define put_eff_id(buf, id) _put_id(buf, 7, id)
168 static void canread_frame_parse(struct canfd_frame *canfd_frame, int maxdlen);
173 static const char * const type_NAMES[type_size] = {
179 // Initialize default can_handler values
180 static struct can_handler can_handler = {
187 * open the can socket
189 static int open_can_dev()
191 const int canfd_on = 1;
193 struct timeval timeout = {1,0};
194 openxc_CanMessage *can_msg;
196 DEBUG(interface, "open_can_dev: CAN Handler socket : %d", can_handler.socket);
197 close(can_handler.socket);
199 can_handler.socket = socket(PF_CAN, SOCK_RAW, CAN_RAW);
200 if (can_handler.socket < 0)
202 ERROR(interface, "open_can_dev: socket could not be created");
206 /* Set timeout for read */
207 setsockopt(can_handler.socket, SOL_SOCKET, SO_RCVTIMEO, (char *)&timeout, sizeof(timeout));
208 /* try to switch the socket into CAN_FD mode */
209 can_msg->has_frame_format = true;
210 if (setsockopt(can_handler.socket, SOL_CAN_RAW, CAN_RAW_FD_FRAMES, &canfd_on, sizeof(canfd_on)) < 0)
212 NOTICE(interface, "open_can_dev: Can not switch into CAN Extended frame format.");
213 can_msg->frame_format = openxc_CanMessage_FrameFormat_STANDARD;
215 can_msg->frame_format = openxc_CanMessage_FrameFormat_EXTENDED;
218 /* Attempts to open a socket to CAN bus */
219 strcpy(ifr.ifr_name, can_handler.device);
220 if(ioctl(can_handler.socket, SIOCGIFINDEX, &ifr) < 0)
222 ERROR(interface, "open_can_dev: ioctl failed");
226 can_handler.txAddress.can_family = AF_CAN;
227 can_handler.txAddress.can_ifindex = ifr.ifr_ifindex;
229 /* And bind it to txAddress */
230 if (bind(can_handler.socket, (struct sockaddr *)&can_handler.txAddress, sizeof(can_handler.txAddress)) < 0)
232 ERROR(interface, "open_can_dev: bind failed");
236 fcntl(can_handler.socket, F_SETFL, O_NONBLOCK);
237 can_handler.msg = can_msg;
241 close(can_handler.socket);
242 can_handler.socket = -1;
247 static int write_can()
251 rc = can_handler.socket;
255 * TODO change old hvac write can frame to generic on_event
257 rc = sendto(can_handler.socket, &canfd_frame, sizeof(struct canfd_frame), 0,
258 (struct sockaddr*)&can_handler.txAddress, sizeof(can_handler.txAddress));
261 ERROR(interface, "Sending CAN frame failed.");
266 ERROR(interface, "socket not initialized. Attempt to reopen can device socket.");
273 * Read on CAN bus and return how much bytes has been read.
275 static int read_can()
277 int bytes_read, maxdlen;
279 bytes_read = read(can_handler.socket, &canfd_frame, sizeof(struct canfd_frame));
283 if (errno == ENETDOWN) {
284 ERROR(interface, "%s: interface down", can_handler.device);
286 ERROR(interface, "Error reading CAN bus");
290 /* CAN frame integrity check */
291 if ((size_t)bytes_read == CAN_MTU)
292 maxdlen = CAN_MAX_DLEN;
293 else if ((size_t)bytes_read == CANFD_MTU)
294 maxdlen = CANFD_MAX_DLEN;
297 ERROR(interface, "CAN frame incomplete");
301 canread_frame_parse(&canfd_frame, maxdlen);
305 * Parse the CAN frame data payload as a CAN packet
306 * TODO: parse as an OpenXC Can Message
308 static void canread_frame_parse(struct canfd_frame *canfd_frame, int maxdlen)
311 int len = (canfd_frame->len > maxdlen) ? maxdlen : canfd_frame->len;
314 if (canfd_frame->can_id & CAN_ERR_FLAG) {
315 put_eff_id(buf, canfd_frame->can_id & (CAN_ERR_MASK|CAN_ERR_FLAG));
318 } else if (canfd_frame->can_id & CAN_EFF_FLAG) {
319 put_eff_id(buf, canfd_frame->can_id & CAN_EFF_MASK);
323 put_sff_id(buf, canfd_frame->can_id & CAN_SFF_MASK);
328 /* standard CAN frames may have RTR enabled. There are no ERR frames with RTR */
329 if (maxdlen == CAN_MAX_DLEN && canfd_frame->can_id & CAN_RTR_FLAG) {
331 /* print a given CAN 2.0B DLC if it's not zero */
332 if (canfd_frame->len && canfd_frame->len <= CAN_MAX_DLC)
333 buf[offset++] = hex_asc_upper[canfd_frame->len & 0xF];
338 if (maxdlen == CANFD_MAX_DLEN) {
339 /* add CAN FD specific escape char and flags */
341 buf[offset++] = hex_asc_upper[canfd_frame->flags & 0xF];
344 for (i = 0; i < len; i++) {
345 put_hex_byte(buf + offset, canfd_frame->data[i]);
351 can_message->has_id = true;
352 can_message->id = msg.id; // TODO make the parsing to extract id from data and only return left data into msg.msg_iov
353 can_message->has_data = true;
354 can_message->data = msg.msg_iov;
358 /***************************************************************************************/
359 /***************************************************************************************/
362 /** SECTION: MANAGING EVENTS **/
365 /***************************************************************************************/
366 /***************************************************************************************/
367 static int connect_to_event_loop();
370 * called on an event on the CAN bus
372 static int on_event(sd_event_source *s, int fd, uint32_t revents, void *userdata)
374 openxc_CanMessage can_message;
376 /* read available data */
377 if ((revents & EPOLLIN) != 0)
379 read_can(&can_message);
383 /* check if error or hangup */
384 if ((revents & (EPOLLERR|EPOLLRDHUP|EPOLLHUP)) != 0)
386 sd_event_source_unref(s);
388 connect_to_event_loop();
395 * get or create an event handler for the type
396 * TODO: implement function and handle retrieve or create an event as needed
398 static struct event *event_get(enum type type)
403 static struct event *event_of_id(int id)
408 /*****************************************************************************************/
409 /*****************************************************************************************/
412 /** SECTION: BINDING VERBS IMPLEMENTATION **/
415 /*****************************************************************************************/
416 /*****************************************************************************************/
418 * Returns the type corresponding to the given name
420 static enum type type_of_name(const char *name)
425 for (result = 0 ; result < type_size; result++)
426 if (strcmp(type_NAMES[result], name) == 0)
432 * extract a valid type from the request
434 static int get_type_for_req(struct afb_req req, enum type *type)
436 if ((*type = type_of_name(afb_req_value(req, "type"))) != type_INVALID)
438 afb_req_fail(req, "unknown-type", NULL);
443 * subscribe to notification of new CAN messages
445 * parameters of the subscription are:
447 * TODO type: string: choose between CAN and OBDII messages formats.
449 * returns an object with 2 fields:
451 * name: string: the name of the event without its prefix
452 * id: integer: a numeric identifier of the event to be used for unsubscribing
454 static void subscribe(struct afb_req req)
459 struct json_object *json;
461 if (get_type_for_req(req, &type))
463 event = event_get(type);
465 afb_req_fail(req, "out-of-memory", NULL);
466 else if (afb_req_subscribe(req, event->event) != 0)
467 afb_req_fail_f(req, "failed", "afb_req_subscribe returned an error: %m");
470 json = json_object_new_object();
471 json_object_object_add(json, "name", json_object_new_string(event->name));
472 json_object_object_add(json, "id", json_object_new_int(event->id));
473 afb_req_success(req, json, NULL);
479 * unsubscribe a previous subscription
481 * parameters of the unsubscription are:
483 * id: integer: the numeric identifier of the event as returned when subscribing
485 static void unsubscribe(struct afb_req req)
490 id = afb_req_value(req, "id");
492 afb_req_fail(req, "missing-id", NULL);
495 event = event_of_id(atoi(id));
497 afb_req_fail(req, "bad-id", NULL);
500 afb_req_unsubscribe(req, event->event);
501 afb_req_success(req, NULL, NULL);
506 static int connect_to_event_loop()
508 sd_event_source *source;
513 if (can_handler.socket < 0)
515 return can_handler.socket;
518 rc = sd_event_add_io(afb_daemon_get_event_loop(interface->daemon), &source, can_handler.socket, EPOLLIN, on_event, NULL);
521 close(can_handler.socket);
522 ERROR(interface, "Can't connect CAN bus %s to the event loop", can_handler.device);
525 NOTICE(interface, "Connected CAN bus %s to the event loop", can_handler.device);
532 // TODO: Have to change session management flag to AFB_SESSION_CHECK to use token auth
533 static const struct afb_verb_desc_v1 verbs[]=
535 { .name= "subscribe", .session= AFB_SESSION_NONE, .callback= subscribe, .info= "subscribe to notification of CAN bus messages." },
536 { .name= "unsubscribe", .session= AFB_SESSION_NONE, .callback= unsubscribe, .info= "unsubscribe a previous subscription." },
540 static const struct afb_binding binding_desc = {
541 .type = AFB_BINDING_VERSION_1,
543 .info = "CAN bus service",
549 const struct afb_binding *afbBindingV1Register (const struct afb_binding_interface *itf)
553 return &binding_desc;
556 int afbBindingV1ServiceInit(struct afb_service service)
558 return connect_to_event_loop();