cangw: Print error message on misspelled interface

[can-utils.git] / isotprecv.c

diff --git a/isotprecv.c b/isotprecv.c
index 2e0e81b5d8d2ca5d5e43f4ef105c793f951e7688..763da39315efe600ca03336c7858dada6165995b 100644 (file)
--- a/isotprecv.c
+++ b/isotprecv.c
@@ -64,8 +64,8 @@ void print_usage(char *prg)
        fprintf(stderr, "Options: -s <can_id>  (source can_id. Use 8 digits for extended IDs)\n");
        fprintf(stderr, "         -d <can_id>  (destination can_id. Use 8 digits for extended IDs)\n");
        fprintf(stderr, "         -x <addr>[:<rxaddr>] (extended addressing / opt. separate rxaddr)\n");
-       fprintf(stderr, "         -p <byte>    (set and enable padding byte)\n");
-       fprintf(stderr, "         -P <mode>    (check padding in SF/CF. (l)ength (c)ontent (a)ll)\n");
+       fprintf(stderr, "         -p [tx]:[rx] (set and enable tx/rx padding bytes)\n");
+       fprintf(stderr, "         -P <mode>    (check rx padding for (l)ength (c)ontent (a)ll)\n");
        fprintf(stderr, "         -b <bs>      (blocksize. 0 = off)\n");
        fprintf(stderr, "         -m <val>     (STmin in ms/ns. See spec.)\n");
        fprintf(stderr, "         -f <time ns> (force rx stmin value in nanosecs)\n");
@@ -81,7 +81,6 @@ int main(int argc, char **argv)
 {
     int s;
     struct sockaddr_can addr;
-    struct ifreq ifr;
     static struct can_isotp_options opts;
     static struct can_isotp_fc_options fcopts;
     static struct can_isotp_ll_options llopts;
@@ -128,9 +127,24 @@ int main(int argc, char **argv)
            }
 
            case 'p':
-                   opts.flags |= CAN_ISOTP_RX_PADDING;
-                   opts.rxpad_content = strtoul(optarg, (char **)NULL, 16) & 0xFF;
+           {
+                   int elements = sscanf(optarg, "%hhx:%hhx",
+                                         &opts.txpad_content,
+                                         &opts.rxpad_content);
+
+                   if (elements == 1)
+                           opts.flags |= CAN_ISOTP_TX_PADDING;
+                   else if (elements == 2)
+                           opts.flags |= (CAN_ISOTP_TX_PADDING | CAN_ISOTP_RX_PADDING);
+                   else if (sscanf(optarg, ":%hhx", &opts.rxpad_content) == 1)
+                           opts.flags |= CAN_ISOTP_RX_PADDING;
+                   else {
+                           printf("incorrect padding values '%s'.\n", optarg);
+                           print_usage(basename(argv[0]));
+                           exit(0);
+                   }
                    break;
+           }
 
            case 'P':
                    if (optarg[0] == 'l')
@@ -217,9 +231,7 @@ int main(int argc, char **argv)
            setsockopt(s, SOL_CAN_ISOTP, CAN_ISOTP_RX_STMIN, &force_rx_stmin, sizeof(force_rx_stmin));
 
     addr.can_family = AF_CAN;
-    strcpy(ifr.ifr_name, argv[optind]);
-    ioctl(s, SIOCGIFINDEX, &ifr);
-    addr.can_ifindex = ifr.ifr_ifindex;
+    addr.can_ifindex = if_nametoindex(argv[optind]);
 
     if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
        perror("bind");