diff options
Diffstat (limited to 'low-can-binding.cpp')
-rw-r--r-- | low-can-binding.cpp | 296 |
1 files changed, 296 insertions, 0 deletions
diff --git a/low-can-binding.cpp b/low-can-binding.cpp new file mode 100644 index 0000000..017a90a --- /dev/null +++ b/low-can-binding.cpp @@ -0,0 +1,296 @@ + */ + +#include <unistd.h> +#include <sys/types.h> +#include <sys/socket.h> +#include <sys/ioctl.h> +#include <net/if.h> +#include <linux/can.h> +#include <linux/can/raw.h> +#include <fcntl.h> +#include <systemd/sd-event.h> +#include <errno.h> +#include <vector> +#include <map> +#include <queue> +#include <string> +#include <functional> +#include <memory> +#include <thread> + +#include <json-c/json.h> +#include <openxc.pb.h> + +#include <afb/afb-binding.h> +#include <afb/afb-service-itf.h> + +#include "ll-can-binding.h" +#include "obd2.h" + +/* + * Interface between the daemon and the binding + */ +static const struct afb_binding_interface *interface; + +/******************************************************************************** +* +* CanBus method implementation +* +*********************************************************************************/ + +int CanBus::open() +{ + const int canfd_on = 1; + struct ifreq ifr; + struct timeval timeout = {1, 0}; + + DEBUG(interface, "open_can_dev: CAN Handler socket : %d", socket); + if (socket >= 0) + close(socket); + + socket = socket(PF_CAN, SOCK_RAW, CAN_RAW); + if (socket < 0) + { + ERROR(interface, "open_can_dev: socket could not be created"); + } + else + { + /* Set timeout for read */ + setsockopt(socket, SOL_SOCKET, SO_RCVTIMEO, (char *)&timeout, sizeof(timeout)); + /* try to switch the socket into CAN_FD mode */ + if (setsockopt(socket, SOL_CAN_RAW, CAN_RAW_FD_FRAMES, &canfd_on, sizeof(canfd_on)) < 0) + { + NOTICE(interface, "open_can_dev: Can not switch into CAN Extended frame format."); + is_fdmode_on = false; + } else { + is_fdmode_on = true; + } + + /* Attempts to open a socket to CAN bus */ + strcpy(ifr.ifr_name, device); + if(ioctl(socket, SIOCGIFINDEX, &ifr) < 0) + ERROR(interface, "open_can_dev: ioctl failed"); + else + { + txAddress.can_family = AF_CAN; + txAddress.can_ifindex = ifr.ifr_ifindex; + + /* And bind it to txAddress */ + if (bind(socket, (struct sockaddr *)&txAddress, sizeof(txAddress)) < 0) + { + ERROR(interface, "open_can_dev: bind failed"); + } + else + { + fcntl(socket, F_SETFL, O_NONBLOCK); + return 0; + } + } + close(socket); + socket = -1; + } + return -1; +} + +int CanBus::close() +{ + close(socket); + socket = -1; +} + +void CanBus::start_threads() +{ + std::queue <canfd_frame> canfd_frame_queue; + std::queue <openxc_can_message_type> can_message_queue; + + th_reading = std::thread(can_reader, interface, socket, canfd_frame_queue); + th_decoding = std::thread(can_decoder, interface, canfd_frame_queue, can_message_queue); + th_pushing = std::thread(can_event_push, interface, can_message_queue); +} + +/******************************************************************************** +* +* Event management +* +*********************************************************************************/ + +/* + * TBF TBF TBF + * called on an event on the CAN bus + */ +static int on_event(sd_event_source *s, int fd, uint32_t revents, void *userdata) +{ + openxc_CanMessage can_message; + + can_message = openxc_CanMessage_init_default; + + /* read available data */ + if ((revents & EPOLLIN) != 0) + { + read_can(&can_message); + send_event(); + } + + /* check if error or hangup */ + if ((revents & (EPOLLERR|EPOLLRDHUP|EPOLLHUP)) != 0) + { + sd_event_source_unref(s); + close(fd); + connect_to_event_loop(); + } + + return 0; +} + +/* + * Get the event loop running. + * Will trigger on_event function on EPOLLIN event on socket + * + * Return 0 or positive value on success. Else negative value for failure. + */ +static int connect_to_event_loop(CanBus &CanBus_handler) +{ + sd_event *event_loop; + sd_event_source *source; + int rc; + + if (CanBus_handler.socket < 0) + { + return CanBus_handler.socket; + } + + event_loop = afb_daemon_get_event_loop(interface->daemon); + rc = sd_event_add_io(event_loop, &source, CanBus_handler.socket, EPOLLIN, on_event, NULL); + if (rc < 0) + { + CanBus_handler.close(); + ERROR(interface, "Can't connect CAN bus %s to the event loop", CanBus_handler.device); + } else + { + NOTICE(interface, "Connected CAN bus %s to the event loop", CanBus_handler.device); + } + + return rc; +} + +/******************************************************************************** +* +* Subscription and unsubscription +* +*********************************************************************************/ + +static int subscribe_unsubscribe_sig(struct afb_req request, int subscribe, struct signal *sig) +{ + if (!afb_event_is_valid(sig->event)) { + if (!subscribe) + return 1; + sig->event = afb_daemon_make_event(afbitf->daemon, sig->name); + if (!afb_event_is_valid(sig->event)) { + return 0; + } + } + + if (((subscribe ? afb_req_subscribe : afb_req_unsubscribe)(request, sig->event)) < 0) { + return 0; + } + + return 1; +} + +static int subscribe_unsubscribe_all(struct afb_req request, int subscribe) +{ + int i, n, e; + + n = sizeof OBD2_PIDS / sizeof * OBD2_PIDS; + e = 0; + for (i = 0 ; i < n ; i++) + e += !subscribe_unsubscribe_sig(request, subscribe, &OBD2_PIDS[i]); + return e == 0; +} + +static int subscribe_unsubscribe_name(struct afb_req request, int subscribe, const char *name) +{ + struct signal *sig; + + if (0 == strcmp(name, "*")) + return subscribe_unsubscribe_all(request, subscribe); + + sig = getsig(name); + if (sig == NULL) { + return 0; + } + + return subscribe_unsubscribe_sig(request, subscribe, sig); +} + +static void subscribe_unsubscribe(struct afb_req request, int subscribe) +{ + int ok, i, n; + struct json_object *args, *a, *x; + + /* makes the subscription/unsubscription */ + args = afb_req_json(request); + if (args == NULL || !json_object_object_get_ex(args, "event", &a)) { + ok = subscribe_unsubscribe_all(request, subscribe); + } else if (json_object_get_type(a) != json_type_array) { + ok = subscribe_unsubscribe_name(request, subscribe, json_object_get_string(a)); + } else { + n = json_object_array_length(a); + ok = 0; + for (i = 0 ; i < n ; i++) { + x = json_object_array_get_idx(a, i); + if (subscribe_unsubscribe_name(request, subscribe, json_object_get_string(x))) + ok++; + } + ok = (ok == n); + } + + /* send the report */ + if (ok) + afb_req_success(request, NULL, NULL); + else + afb_req_fail(request, "error", NULL); +} + +static void subscribe(struct afb_req request) +{ + subscribe_unsubscribe(request, 1); +} + +static void unsubscribe(struct afb_req request) +{ + subscribe_unsubscribe(request, 0); +} +static const struct afb_verb_desc_v1 verbs[]= +{ + { .name= "subscribe", .session= AFB_SESSION_NONE, .callback= subscribe, .info= "subscribe to notification of CAN bus messages." }, + { .name= "unsubscribe", .session= AFB_SESSION_NONE, .callback= unsubscribe, .info= "unsubscribe a previous subscription." }, + {NULL} +}; + +static const struct afb_binding binding_desc = { + .type = AFB_BINDING_VERSION_1, + .v1 = { + .info = "CAN bus service", + .prefix = "can", + .verbs = verbs + } +}; + +const struct afb_binding *afbBindingV1Register (const struct afb_binding_interface *itf) +{ + interface = itf; + + return &binding_desc; +} + +int afbBindingV1ServiceInit(struct afb_service service) +{ + /* Open JSON conf file */ + + /* Open CAN socket */ + CanBus_handler.open(); + CanBus_handler.start_threads(); + + return connect_to_event_loop(CanBus_handler); +} |