Merge b541771b7b into 7a4dd732af

README.md

@@ -11,7 +11,7 @@ subsystem (aka SocketCAN):
 
 * candump : display, filter and log CAN data to files
 * canplayer : replay CAN logfiles
-* cansend : send a single frame
+* cansend : send single frames
 * cangen : generate (random) CAN traffic
 * cansniffer : display CAN data content differences (just 11bit CAN IDs)
 

cansend.c

@@ -60,31 +60,15 @@ int main(int argc, char **argv)
 	int s; /* can raw socket */ 
 	int required_mtu;
 	int mtu;
-	int enable_canfd = 1;
+	int enable_canfd = 0;
+	int framecnt;
 	struct sockaddr_can addr;
 	struct canfd_frame frame;
 	struct ifreq ifr;
 
 	/* check command line options */
-	if (argc != 3) {
+	if (argc < 3) {
-		fprintf(stderr, "Usage: %s <device> <can_frame>.\n", argv[0]);
+		fprintf(stderr, "Usage: %s <device> <can_frame>...\n", argv[0]);
-		return 1;
-	}
-
-	/* parse CAN frame */
-	required_mtu = parse_canframe(argv[2], &frame);
-	if (!required_mtu){
-		fprintf(stderr, "\nWrong CAN-frame format! Try:\n\n");
-		fprintf(stderr, "    <can_id>#{R|data}          for CAN 2.0 frames\n");
-		fprintf(stderr, "    <can_id>##<flags>{data}    for CAN FD frames\n\n");
-		fprintf(stderr, "<can_id> can have 3 (SFF) or 8 (EFF) hex chars\n");
-		fprintf(stderr, "{data} has 0..8 (0..64 CAN FD) ASCII hex-values (optionally");
-		fprintf(stderr, " separated by '.')\n");
-		fprintf(stderr, "<flags> a single ASCII Hex value (0 .. F) which defines");
-		fprintf(stderr, " canfd_frame.flags\n\n");
-		fprintf(stderr, "e.g. 5A1#11.2233.44556677.88 / 123#DEADBEEF / 5AA# / ");
-		fprintf(stderr, "123##1 / 213##311\n     1F334455#1122334455667788 / 123#R ");
-		fprintf(stderr, "for remote transmission request.\n\n");
 		return 1;
 	}
 
@@ -106,8 +90,38 @@ int main(int argc, char **argv)
 	addr.can_family = AF_CAN;
 	addr.can_ifindex = ifr.ifr_ifindex;
 
+	/* disable default receive filter on this RAW socket */
+	/* This is obsolete as we do not read from the socket at all, but for */
+	/* this reason we can remove the receive list in the Kernel to save a */
+	/* little (really a very little!) CPU usage.                          */
+	setsockopt(s, SOL_CAN_RAW, CAN_RAW_FILTER, NULL, 0);
+
+	if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
+		perror("bind");
+		return 1;
+	}
+
+	for (framecnt = 2; framecnt < argc; framecnt++) {
+		/* parse CAN frame */
+		required_mtu = parse_canframe(argv[framecnt], &frame);
+		if (!required_mtu){
+			fprintf(stderr, "\nWrong CAN-frame format! Try:\n\n");
+			fprintf(stderr, "    <can_id>#{R|data}          for CAN 2.0 frames\n");
+			fprintf(stderr, "    <can_id>##<flags>{data}    for CAN FD frames\n\n");
+			fprintf(stderr, "<can_id> can have 3 (SFF) or 8 (EFF) hex chars\n");
+			fprintf(stderr, "{data} has 0..8 (0..64 CAN FD) ASCII hex-values (optionally");
+			fprintf(stderr, " separated by '.')\n");
+			fprintf(stderr, "<flags> a single ASCII Hex value (0 .. F) which defines");
+			fprintf(stderr, " canfd_frame.flags\n\n");
+			fprintf(stderr, "e.g. 5A1#11.2233.44556677.88 / 123#DEADBEEF / 5AA# / ");
+			fprintf(stderr, "123##1 / 213##311\n     1F334455#1122334455667788 / 123#R ");
+			fprintf(stderr, "for remote transmission request.\n\n");
+			return 1;
+		}
+
 		if (required_mtu > CAN_MTU) {
 
+			if (enable_canfd == 0) {
 				/* check if the frame fits into the CAN netdevice */
 				if (ioctl(s, SIOCGIFMTU, &ifr) < 0) {
 					perror("SIOCGIFMTU");
@@ -121,32 +135,24 @@ int main(int argc, char **argv)
 				}
 
 				/* interface is ok - try to switch the socket into CAN FD mode */
+				enable_canfd = 1;
 				if (setsockopt(s, SOL_CAN_RAW, CAN_RAW_FD_FRAMES,
 					&enable_canfd, sizeof(enable_canfd))){
 					printf("error when enabling CAN FD support\n");
 					return 1;
 				}
+			}
 
 			/* ensure discrete CAN FD length values 0..8, 12, 16, 20, 24, 32, 64 */
 			frame.len = can_dlc2len(can_len2dlc(frame.len));
 		}
 
-	/* disable default receive filter on this RAW socket */
-	/* This is obsolete as we do not read from the socket at all, but for */
-	/* this reason we can remove the receive list in the Kernel to save a */
-	/* little (really a very little!) CPU usage.                          */
-	setsockopt(s, SOL_CAN_RAW, CAN_RAW_FILTER, NULL, 0);
-
-	if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
-		perror("bind");
-		return 1;
-	}
-
 		/* send frame */
 		if (write(s, &frame, required_mtu) != required_mtu) {
 			perror("write");
 			return 1;
 		}
+	}
 
 	close(s);