Enable error frame reception in raw mode (#67)

* Enable error frame reception in raw mode

* add error_mask option

Author: occam25

src/socketcand.c

@@ -64,6 +64,7 @@ int cmd_index = 0;
 char *description;
 char *afuxname;
 int more_elements = 0;
+can_err_mask_t error_mask = 0;
 struct sockaddr_in saddr, broadcast_addr;
 struct sockaddr_un unaddr;
 socklen_t unaddrlen;
@@ -212,11 +213,12 @@ int main(int argc, char **argv)
 			{ "daemon", no_argument, 0, 'd' },
 			{ "version", no_argument, 0, 'z' },
 			{ "no-beacon", no_argument, 0, 'n' },
+			{ "error-mask", required_argument, 0, 'e' },
 			{ "help", no_argument, 0, 'h' },
 			{ 0, 0, 0, 0 }
 		};
 
-		c = getopt_long(argc, argv, "vi:p:qu:l:dznh", long_options, &option_index);
+		c = getopt_long(argc, argv, "vi:p:qu:l:dzne:h", long_options, &option_index);
 
 		if (c == -1)
 			break;
@@ -269,6 +271,10 @@ int main(int argc, char **argv)
 			disable_beacon = 1;
 			break;
 
+		case 'e':
+			error_mask = strtoul(optarg, NULL, 16);
+			break;
+
 		case 'h':
 			print_usage();
 			return 0;
@@ -651,6 +657,7 @@ void print_usage(void)
 	printf("\t-l <interface> (changes the default network interface the daemon will\n\t\tbind to - default: %s)\n", DEFAULT_INTERFACE);
 	printf("\t-u <name> (the AF_UNIX socket path - abstract name when leading '/' is missing)\n\t\t(N.B. the AF_UNIX binding will supersede the port/interface settings)\n");
 	printf("\t-n (deactivates the discovery beacon)\n");
+	printf("\t-e <error_mask> (enable CAN error frames in raw mode providing an hexadecimal error mask, e.g: 0x1FFFFFFF)\n");
 	printf("\t-d (set this flag if you want log to syslog instead of STDOUT)\n");
 	printf("\t-h (prints this message)\n");
 }

src/socketcand.h

@@ -2,6 +2,7 @@
 
 #include <pthread.h>
 #include <syslog.h>
+#include <linux/can.h>
 
 /* max. length for ISO 15765-2 PDUs */
 #define ISOTPLEN 4095
@@ -69,6 +70,7 @@ extern pthread_t statistics_thread;
 extern int more_elements;
 extern struct sockaddr_in broadcast_addr;
 extern struct sockaddr_in saddr;
+extern can_err_mask_t error_mask;
 
 int receive_command(int socket, char *buf);
 int state_changed(char *buf, int current_state);

src/state_raw.c

@@ -21,6 +21,7 @@
 #include <syslog.h>
 
 #include <linux/can.h>
+#include <linux/can/raw.h>
 
 int raw_socket;
 struct ifreq ifr;
@@ -62,6 +63,15 @@ void state_raw()
 			return;
 		}
 
+		if (error_mask != 0) {
+			can_err_mask_t err_mask = (error_mask & CAN_ERR_MASK);
+			if (setsockopt(raw_socket, SOL_CAN_RAW, CAN_RAW_ERR_FILTER, &err_mask, sizeof(err_mask)) < 0) {
+				PRINT_ERROR("Could not enable CAN_RAW_ERR_FILTER\n");
+				state = STATE_SHUTDOWN;
+				return;
+			}
+		}
+
 		if (bind(raw_socket, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
 			PRINT_ERROR("Error while binding RAW socket %s\n", strerror(errno));
 			state = STATE_SHUTDOWN;