Added some sample code to use CAN interfaces with PF_PACKET sockets.

[socketcan-devel.git] / test / tst-packet.c

diff --git a/test/tst-packet.c b/test/tst-packet.c
new file mode 100644 (file)
index 0000000..a7353b7
--- /dev/null
+++ b/test/tst-packet.c
@@ -0,0 +1,167 @@
+/*
+ *  $Id$
+ */
+
+/*
+ * tst-packet.c - send and receive CAN frames via PF_PACKET sockets
+ *
+ * Remark: The sending of CAN frames via PF_PACKET does not work for
+ * virtual CAN devices (vcan) as the packet type is not set to
+ * PACKET_LOOPBACK by the packet socket, so you'll never get something
+ * back (btw the outgoing vcan packet counters are updated correctly).
+ *
+ * Copyright (c) 2002-2009 Volkswagen Group Electronic Research
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Volkswagen nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * Alternatively, provided that this notice is retained in full, this
+ * software may be distributed under the terms of the GNU General
+ * Public License ("GPL") version 2, in which case the provisions of the
+ * GPL apply INSTEAD OF those given above.
+ *
+ * The provided data structures and external interfaces from this code
+ * are not restricted to be used by modules with a GPL compatible license.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * Send feedback to <socketcan-users@lists.berlios.de>
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/ioctl.h>
+#include <net/if.h>
+#include <netinet/in.h>                /* for htons() */
+
+#include <linux/if_packet.h>
+#include <linux/if_ether.h>    /* for ETH_P_CAN */
+#include <linux/can.h>         /* for struct can_frame */
+
+int main(int argc, char **argv)
+{
+       int s;
+       struct can_frame frame;
+       int nbytes, i;
+       static struct ifreq ifr;
+       static struct sockaddr_ll sll;
+       char *ifname = "vcan2";
+       int ifindex;
+       int opt;
+       int send_one_frame = 0;
+
+       while ((opt = getopt(argc, argv, "i:s")) != -1) {
+               switch (opt) {
+
+               case 'i':
+                       ifname = optarg;
+                       break;
+
+               case 's':
+                       send_one_frame = 1;
+                       break;
+
+               default:
+                       fprintf(stderr, "Unknown option %c\n", opt);
+                       break;
+               }
+       }
+
+       s = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_CAN));
+       if (s < 0) {
+               perror("socket");
+               return 1;
+       }
+
+       if (strcmp(ifname, "any") == 0)
+               ifindex = 0;
+       else {
+               strcpy(ifr.ifr_name, ifname);
+               ioctl(s, SIOCGIFINDEX, &ifr);
+               ifindex = ifr.ifr_ifindex;
+       }
+
+       sll.sll_family   = AF_PACKET;
+       sll.sll_ifindex  = ifindex;
+       sll.sll_protocol = htons(ETH_P_CAN);
+
+       if (bind(s, (struct sockaddr *)&sll, sizeof(sll)) < 0) {
+               perror("bind");
+               return 1;
+       }
+
+       if(send_one_frame) {
+
+               frame.can_id  = 0x123;
+               frame.can_dlc = 2;
+               frame.data[0] = 0x11;
+               frame.data[1] = 0x22;
+
+               nbytes = write(s, &frame, sizeof(struct can_frame));
+               if (nbytes < 0) {
+                       perror("write");
+                       return 1;
+               }
+               if (nbytes != sizeof(struct can_frame)) {
+                       perror("write_len");
+                       return 1;
+               }
+       }
+
+       while (1) {
+
+               if ((nbytes = read(s, &frame, sizeof(struct can_frame))) < 0) {
+                       perror("read");
+                       return 1;
+               } else if (nbytes < sizeof(struct can_frame)) {
+                       fprintf(stderr, "read: incomplete CAN frame\n");
+                       return 1;
+               } else {
+                       if (frame.can_id & CAN_EFF_FLAG)
+                               printf("%8X  ", frame.can_id & CAN_EFF_MASK);
+                       else
+                               printf("%3X  ", frame.can_id & CAN_SFF_MASK);
+           
+                       printf("[%d] ", frame.can_dlc);
+           
+                       for (i = 0; i < frame.can_dlc; i++) {
+                               printf("%02X ", frame.data[i]);
+                       }
+                       if (frame.can_id & CAN_RTR_FLAG)
+                               printf("remote request");
+                       printf("\n");
+                       fflush(stdout);
+               }
+       }
+
+       close(s);
+
+       return 0;
+}