Re-implementation in C++ and separate threads to

read, decode and pushing on the event loop.

Old code has been moved into obsolete directory.

Change-Id: Ia389ab84a1dc566c48e0269f2466843de0e51158
Signed-off-by: Romain Forlot <romain.forlot@iot.bzh>

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);
+}