First commit: work has to be done...

Change-Id: Iad7a1780280064e0ff6970c21423ba825dd333dd
Signed-off-by: Romain Forlot <romain.forlot@iot.bzh>

2 files changed, 515 insertions, 0 deletions

diff --git a/export.map b/export.map
new file mode 100644
index 00000000..52c1b4aa
--- /dev/null
+++ b/export.map
@@ -0,0 +1 @@
+{ global: afbBindingV1*; local: *; };
diff --git a/iotbzh-CAN-binding.c b/iotbzh-CAN-binding.c
new file mode 100644
index 00000000..293ad3bc
--- /dev/null
+++ b/iotbzh-CAN-binding.c
@@ -0,0 +1,514 @@
+/*
+ * Copyright (C) 2015, 2016 "IoT.bzh"
+ * Author "Romain Forlot" <romain.forlot@iot.bzh>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#define _GNU_SOURCE
+
+#include <string.h>
+#include <stdbool.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/ioctl.h>
+#include <net/if.h>
+#include <sys/time.h>
+#include <linux/can.h>
+#include <math.h>
+#include <fcntl.h>
+#include <systemd/sd-event.h>
+
+#include <json-c/json.h>
+
+#include <afb/afb-binding.h>
+#include <afb/afb-service-itf.h>
+
+/*****************************************************************************************/
+/*****************************************************************************************/
+/**											**/
+/**											**/
+/**	   SECTION: GLOBAL VARIABLES							**/
+/**											**/
+/**											**/
+/*****************************************************************************************/
+/*****************************************************************************************/
+
+/*
+ * Interface between the daemon and the binding
+ */
+static const struct afb_binding_interface *interface;
+
+/*
+ * the type of position expected
+ *
+ * here, this type is the selection of protocol
+ */
+enum type {
+	type_OBDII,
+	type_CAN,
+	type_DEFAULT = type_CAN,
+	type_INVALID = -1
+};
+
+#define type_size sizeof(enum type)-2
+
+/*
+ * names of the types
+ */
+static const char * const type_NAMES[type_size] = {
+	"OBDII",
+	"CAN"
+};
+
+struct can_handler {
+	int socket;
+	char *device;
+	char *send_msg;
+	char *read_msg;
+	struct sockaddr_can txAddress;
+};
+
+static struct can_handler can_handler = {
+	.socket = -1,
+	.device = "vcan0"
+};
+
+struct can_frame can_frame;
+
+/*****************************************************************************************/
+/*****************************************************************************************/
+/**											**/
+/**											**/
+/**	   SECTION: UTILITY FUNCTIONS							**/
+/**											**/
+/**											**/
+/*****************************************************************************************/
+/*****************************************************************************************/
+
+/*
+ * @brief Retry a function 3 times
+ *
+ * @param int function(): function that return an int wihtout any parameter
+ *
+ * @ return : 0 if ok, -1 if failed
+ *
+ */
+static int retry( int(*func)());
+static int retry( int(*func)())
+{
+	int i;
+
+	for (i=0;i<4;i++)
+	{
+		if ( (*func)() >= 0)
+		{
+			return 0;
+		}
+		usleep(100000);
+	}
+	return -1;
+}
+
+/*****************************************************************************************/
+/*****************************************************************************************/
+/**											**/
+/**											**/
+/**	   SECTION: HANDLE CAN DEVICE							**/
+/**											**/
+/**											**/
+/*****************************************************************************************/
+/*****************************************************************************************/
+
+static int connect_to_event_loop();
+
+/*
+ * Parse the CAN frame data payload as a CANopen packet
+ * TODO: define can_frame_t
+ */
+int can_frame_parse(canopen_frame_t *canopen_frame, struct can_frame *can_frame)
+{
+    int i;
+
+    if (canopen_frame == NULL || can_frame == NULL)
+    {
+        return -1;
+    }
+
+    bzero((void *)canopen_frame, sizeof(canopen_frame_t));
+
+    //
+    // Parse basic protocol fields
+    //
+
+    if (can_frame->can_id & CAN_EFF_FLAG)
+    {
+        canopen_frame->type = CANOPEN_FLAG_EXTENDED;
+        canopen_frame->id   = can_frame->can_id & CAN_EFF_MASK;
+    }
+    else
+    {
+        canopen_frame->type = CANOPEN_FLAG_STANDARD;
+        canopen_frame->function_code = (can_frame->can_id & 0x00000780U) >> 7;
+        canopen_frame->id            = (can_frame->can_id & 0x0000007FU);
+    }
+
+    canopen_frame->rtr = (can_frame->can_id & CAN_RTR_FLAG) ?
+                         CANOPEN_FLAG_RTR : CANOPEN_FLAG_NORMAL;
+
+    canopen_frame->data_len = can_frame->can_dlc;
+    for (i = 0; i < can_frame->can_dlc; i++)
+    {
+        canopen_frame->payload.data[i] = can_frame->data[i];
+    }
+
+    //
+    // Parse payload data
+    //
+
+    // NMT protocol
+    switch (canopen_frame->function_code)
+    {
+        // ---------------------------------------------------------------------
+        // Network ManagemenT frame: Module Control
+        //
+        case CANOPEN_FC_NMT_MC:
+
+            break;
+
+        // ---------------------------------------------------------------------
+        // Network ManagemenT frame: Node Guarding
+        //
+        case CANOPEN_FC_NMT_NG:
+
+
+            break;
+
+        //default:
+            // unhandled type...
+    }
+
+    return 0;
+}
+
+/*
+ * Read on CAN bus
+ */
+static int read_can()
+{
+	int byte_read;
+
+	byte_read = read(can_handler.socket, &can_frame, sizeof(struct can_frame));
+
+	if (byte_read < 0)
+	{
+		ERROR(interface, "Error reading CAN bus");
+		return -1;
+	}
+
+	if (byte_read < (int)sizeof(struct can_frame))
+	{
+		ERROR(interface, "CAN frame incomplete");
+		return -2;
+	}
+}
+
+/*
+ * called on an event on the CAN bus
+ */
+static int on_event(sd_event_source *s, int fd, uint32_t revents, void *userdata)
+{
+	/* read available data */
+	if ((revents & EPOLLIN) != 0)
+	{
+		read_can();
+//		event_send();
+	}
+
+	/* check if error or hangup */
+	if ((revents & (EPOLLERR|EPOLLRDHUP|EPOLLHUP)) != 0)
+	{
+		sd_event_source_unref(s);
+		close(fd);
+		connect_to_event_loop();
+	}
+
+	return 0;
+}
+
+/*
+ * open the can socket
+ */
+static int open_can_dev()
+{
+	struct ifreq ifr;
+	struct timeval timeout = {1,0};
+
+	DEBUG(interface, "open_can_dev: CAN Handler socket : %d", can_handler.socket);
+	close(can_handler.socket);
+
+	can_handler.socket = socket(PF_CAN, SOCK_RAW, CAN_RAW);
+	if (can_handler.socket < 0)
+	{
+		ERROR(interface, "open_can_dev: socket could not be created");
+	}
+	else
+	{
+		// Set timeout for read
+		setsockopt(can_handler.socket, SOL_SOCKET, SO_RCVTIMEO, (char *)&timeout, sizeof(timeout));
+		// Attempts to open a socket to CAN bus
+		strcpy(ifr.ifr_name, can_handler.device);
+		if(ioctl(can_handler.socket, SIOCGIFINDEX, &ifr) < 0)
+		{
+			ERROR(interface, "open_can_dev: ioctl failed");
+		}
+		else
+		{
+			can_handler.txAddress.can_family = AF_CAN;
+			can_handler.txAddress.can_ifindex = ifr.ifr_ifindex;
+
+			// And bind it to txAddress
+			if (bind(can_handler.socket, (struct sockaddr *)&can_handler.txAddress, sizeof(can_handler.txAddress)) < 0)
+			{
+				ERROR(interface, "open_can_dev: bind failed");
+			}
+			else
+			{
+				fcntl(can_handler.socket, F_SETFL, O_NONBLOCK);
+				return 0;
+			}
+		}
+		close(can_handler.socket);
+		can_handler.socket = -1;
+	}
+	return -1;
+}
+
+static int write_can()
+{
+	int rc = 0;
+
+	rc = can_handler.socket;
+	if (rc >= 0)
+	{
+/*
+ * TODO change old hvac write can frame to generic on_event
+ */
+		can_frame.can_id = 0x30;
+		can_frame.can_dlc = 8;
+		can_frame.data[0] = 0;
+		can_frame.data[1] = 0;
+		can_frame.data[2] = 0;
+		can_frame.data[3] = 0xf0;
+		can_frame.data[4] = 0;
+		can_frame.data[5] = 1;
+		can_frame.data[6] = 0;
+		can_frame.data[7] = 0;
+
+		DEBUG(interface, "%s: %d %d [%02x %02x %02x %02x %02x %02x %02x %02x]\n",
+			can_handler.send_msg,
+			can_frame.can_id, can_frame.can_dlc,
+			can_frame.data[0], can_frame.data[1], can_frame.data[2], can_frame.data[3],
+			can_frame.data[4], can_frame.data[5], can_frame.data[6], can_frame.data[7]);
+
+		rc = sendto(can_handler.socket, &can_frame, sizeof(struct can_frame), 0,
+			    (struct sockaddr*)&can_handler.txAddress, sizeof(can_handler.txAddress));
+		if (rc < 0)
+		{
+			ERROR(interface, "Sending CAN frame failed.");
+		}
+	}
+	else
+	{
+		ERROR(interface, "socket not initialized. Attempt to reopen can device socket.");
+		retry(open_can_dev);
+	}
+	return rc;
+}
+
+/***************************************************************************************/
+/***************************************************************************************/
+/**                                                                                   **/
+/**                                                                                   **/
+/**       SECTION: MANAGING EVENTS                                                    **/
+/**                                                                                   **/
+/**                                                                                   **/
+/***************************************************************************************/
+/***************************************************************************************/
+
+/*
+ * get or create an event handler for the type
+ * TODO: implement function and handle retrieve or create an event as needed
+ */
+static struct event *event_get(enum type type)
+{
+
+}
+
+static struct event *event_of_id(int id)
+{
+
+}
+
+/*****************************************************************************************/
+/*****************************************************************************************/
+/**											**/
+/**											**/
+/**	   SECTION: BINDING VERBS IMPLEMENTATION					**/
+/**											**/
+/**											**/
+/*****************************************************************************************/
+/*****************************************************************************************/
+/*
+ * Returns the type corresponding to the given name
+ */
+static enum type type_of_name(const char *name)
+{
+	enum type result;
+	if (name == NULL)
+		return type_DEFAULT;
+	for (result = 0 ; result < type_size; result++)
+		if (strcmp(type_NAMES[result], name) == 0)
+			return result;
+	return type_INVALID;
+}
+
+/*
+ * extract a valid type from the request
+ */
+static int get_type_for_req(struct afb_req req, enum type *type)
+{
+	if ((*type = type_of_name(afb_req_value(req, "type"))) != type_INVALID)
+		return 1;
+	afb_req_fail(req, "unknown-type", NULL);
+	return 0;
+}
+
+/*
+ * subscribe to notification of new CAN messages
+ *
+ * parameters of the subscription are:
+ *
+ *    TODO type: string:  choose between CAN and OBDII messages formats.
+ *
+ * returns an object with 2 fields:
+ *
+ *    name:   string:  the name of the event without its prefix
+ *    id:     integer: a numeric identifier of the event to be used for unsubscribing
+ */
+static void subscribe(struct afb_req req)
+{
+	enum type type;
+	const char *period;
+	struct event *event;
+	struct json_object *json;
+
+	if (get_type_for_req(req, &type))
+	{
+		event = event_get(type);
+		if (event == NULL)
+			afb_req_fail(req, "out-of-memory", NULL);
+		else if (afb_req_subscribe(req, event->event) != 0)
+			afb_req_fail_f(req, "failed", "afb_req_subscribe returned an error: %m");
+		else
+		{
+			json = json_object_new_object();
+			json_object_object_add(json, "name", json_object_new_string(event->name));
+			json_object_object_add(json, "id", json_object_new_int(event->id));
+			afb_req_success(req, json, NULL);
+		}
+	}
+}
+
+/*
+ * unsubscribe a previous subscription
+ *
+ * parameters of the unsubscription are:
+ *
+ *    id:   integer: the numeric identifier of the event as returned when subscribing
+ */
+static void unsubscribe(struct afb_req req)
+{
+	const char *id;
+	struct event *event;
+
+	id = afb_req_value(req, "id");
+	if (id == NULL)
+		afb_req_fail(req, "missing-id", NULL);
+	else
+	{
+		event = event_of_id(atoi(id));
+		if (event == NULL)
+			afb_req_fail(req, "bad-id", NULL);
+		else
+		{
+			afb_req_unsubscribe(req, event->event);
+			afb_req_success(req, NULL, NULL);
+		}
+	}
+}
+
+static int connect_to_event_loop()
+{
+	sd_event_source *source;
+	int rc;
+
+	retry(open_can_dev);
+
+	if (can_handler.socket < 0)
+	{
+		return can_handler.socket;
+	}
+
+	rc = sd_event_add_io(afb_daemon_get_event_loop(interface->daemon), &source, can_handler.socket, EPOLLIN, on_event, NULL);
+	if (rc < 0)
+	{
+		close(can_handler.socket);
+		ERROR(interface, "Can't connect CAN bus %s to the event loop", can_handler.device);
+	} else
+	{
+		NOTICE(interface, "Connected CAN bus %s to the event loop", can_handler.device);
+	}
+
+	return rc;
+}
+
+
+// TODO: Have to change session management flag to AFB_SESSION_CHECK to use token auth
+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)
+{
+	return connect_to_event_loop();
+}