candump.c

   1 /*
   2  *  $Id$
   3  */
   4
   5 /*
   6  * candump.c
   7  *
   8  * Copyright (c) 2002-2009 Volkswagen Group Electronic Research
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  * 3. Neither the name of Volkswagen nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * Alternatively, provided that this notice is retained in full, this
  24  * software may be distributed under the terms of the GNU General
  25  * Public License ("GPL") version 2, in which case the provisions of the
  26  * GPL apply INSTEAD OF those given above.
  27  *
  28  * The provided data structures and external interfaces from this code
  29  * are not restricted to be used by modules with a GPL compatible license.
  30  *
  31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  36  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  37  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  38  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  39  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  40  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  41  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
  42  * DAMAGE.
  43  *
  44  * Send feedback to <socketcan-users@lists.berlios.de>
  45  *
  46  */
  47
  48 #include <stdio.h>
  49 #include <stdlib.h>
  50 #include <unistd.h>
  51 #include <string.h>
  52 #include <signal.h>
  53 #include <ctype.h>
  54 #include <libgen.h>
  55 #include <time.h>
  56
  57 #include <sys/time.h>
  58 #include <sys/types.h>
  59 #include <sys/socket.h>
  60 #include <sys/ioctl.h>
  61 #include <sys/uio.h>
  62 #include <net/if.h>
  63
  64 #include <linux/can.h>
  65 #include <linux/can/raw.h>
  66
  67 #include "terminal.h"
  68 #include "lib.h"
  69
  70 #define MAXSOCK 16    /* max. number of CAN interfaces given on the cmdline */
  71 #define MAXIFNAMES 30 /* size of receive name index to omit ioctls */
  72 #define MAXCOL 6      /* number of different colors for colorized output */
  73 #define ANYDEV "any"  /* name of interface to receive from any CAN interface */
  74 #define ANL "\r\n"    /* newline in ASC mode */
  75
  76 #define SILENT_INI 42 /* detect user setting on commandline */
  77 #define SILENT_OFF 0  /* no silent mode */
  78 #define SILENT_ANI 1  /* silent mode with animation */
  79 #define SILENT_ON  2  /* silent mode (completely silent) */
  80
  81 #define BOLD    ATTBOLD
  82 #define RED     ATTBOLD FGRED
  83 #define GREEN   ATTBOLD FGGREEN
  84 #define YELLOW  ATTBOLD FGYELLOW
  85 #define BLUE    ATTBOLD FGBLUE
  86 #define MAGENTA ATTBOLD FGMAGENTA
  87 #define CYAN    ATTBOLD FGCYAN
  88
  89 const char col_on [MAXCOL][19] = {BLUE, RED, GREEN, BOLD, MAGENTA, CYAN};
  90 const char col_off [] = ATTRESET;
  91
  92 static char *cmdlinename[MAXSOCK];
  93 static __u32 dropcnt[MAXSOCK];
  94 static __u32 last_dropcnt[MAXSOCK];
  95 static char devname[MAXIFNAMES][IFNAMSIZ+1];
  96 static int  dindex[MAXIFNAMES];
  97 static int  max_devname_len; /* to prevent frazzled device name output */
  98
  99 #define MAXANI 4
 100 const char anichar[MAXANI] = {'|', '/', '-', '\\'};
 101
 102 extern int optind, opterr, optopt;
 103
 104 static volatile int running = 1;
 105
 106 void print_usage(char *prg)
 107 {
 108         fprintf(stderr, "\nUsage: %s [options] <CAN interface>+\n", prg);
 109         fprintf(stderr, "  (use CTRL-C to terminate %s)\n\n", prg);
 110         fprintf(stderr, "Options: -t <type>   (timestamp: (a)bsolute/(d)elta/(z)ero/(A)bsolute w date)\n");
 111         fprintf(stderr, "         -c          (increment color mode level)\n");
 112         fprintf(stderr, "         -i          (binary output - may exceed 80 chars/line)\n");
 113         fprintf(stderr, "         -a          (enable additional ASCII output)\n");
 114         fprintf(stderr, "         -S          (swap byte order in printed CAN data[] - marked with '%c' )\n", SWAP_DELIMITER);
 115         fprintf(stderr, "         -s <level>  (silent mode - %d: off (default) %d: animation %d: silent)\n", SILENT_OFF, SILENT_ANI, SILENT_ON);
 116         fprintf(stderr, "         -b <can>    (bridge mode - send received frames to <can>)\n");
 117         fprintf(stderr, "         -B <can>    (bridge mode - like '-b' with disabled loopback)\n");
 118         fprintf(stderr, "         -l          (log CAN-frames into file. Sets '-s %d' by default)\n", SILENT_ON);
 119         fprintf(stderr, "         -L          (use log file format on stdout)\n");
 120         fprintf(stderr, "         -n <count>  (terminate after receiption of <count> CAN frames)\n");
 121         fprintf(stderr, "         -r <size>   (set socket receive buffer to <size>)\n");
 122         fprintf(stderr, "         -d          (monitor dropped CAN frames)\n");
 123         fprintf(stderr, "\n");
 124         fprintf(stderr, "Up to %d CAN interfaces with optional filter sets can be specified\n", MAXSOCK);
 125         fprintf(stderr, "on the commandline in the form: <ifname>[,filter]*\n");
 126         fprintf(stderr, "\nComma separated filters can be specified for each given CAN interface:\n");
 127         fprintf(stderr, " <can_id>:<can_mask> (matches when <received_can_id> & mask == can_id & mask)\n");
 128         fprintf(stderr, " <can_id>~<can_mask> (matches when <received_can_id> & mask != can_id & mask)\n");
 129         fprintf(stderr, " #<error_mask>       (set error frame filter, see include/linux/can/error.h)\n");
 130         fprintf(stderr, "\nCAN IDs, masks and data content are given and expected in hexadecimal values.\n");
 131         fprintf(stderr, "When can_id and can_mask are both 8 digits, they are assumed to be 29 bit EFF.\n");
 132         fprintf(stderr, "Without any given filter all data frames are received ('0:0' default filter).\n");
 133         fprintf(stderr, "\nUse interface name '%s' to receive from all CAN interfaces.\n", ANYDEV);
 134         fprintf(stderr, "\nExamples:\n");
 135         fprintf(stderr, "%s -c -c -ta can0,123:7FF,400:700,#000000FF can2,400~7F0 can3 can8\n", prg);
 136         fprintf(stderr, "%s -l any,0~0,#FFFFFFFF    (log only error frames but no(!) data frames)\n", prg);
 137         fprintf(stderr, "%s -l any,0:0,#FFFFFFFF    (log error frames and also all data frames)\n", prg);
 138         fprintf(stderr, "%s vcan2,92345678:DFFFFFFF (match only for extended CAN ID 12345678)\n", prg);
 139         fprintf(stderr, "%s vcan2,123:7FF (matches CAN ID 123 - including EFF and RTR frames)\n", prg);
 140         fprintf(stderr, "%s vcan2,123:C00007FF (matches CAN ID 123 - only SFF and non-RTR frames)\n", prg);
 141         fprintf(stderr, "\n");
 142 }
 143
 144 void sigterm(int signo)
 145 {
 146         running = 0;
 147 }
 148
 149 int idx2dindex(int ifidx, int socket) {
 150
 151         int i;
 152         struct ifreq ifr;
 153
 154         for (i=0; i < MAXIFNAMES; i++) {
 155                 if (dindex[i] == ifidx)
 156                         return i;
 157         }
 158
 159         /* create new interface index cache entry */
 160
 161         /* remove index cache zombies first */
 162         for (i=0; i < MAXIFNAMES; i++) {
 163                 if (dindex[i]) {
 164                         ifr.ifr_ifindex = dindex[i];
 165                         if (ioctl(socket, SIOCGIFNAME, &ifr) < 0)
 166                                 dindex[i] = 0;
 167                 }
 168         }
 169
 170         for (i=0; i < MAXIFNAMES; i++)
 171                 if (!dindex[i]) /* free entry */
 172                         break;
 173
 174         if (i == MAXIFNAMES) {
 175                 fprintf(stderr, "Interface index cache only supports %d interfaces.\n",
 176                        MAXIFNAMES);
 177                 exit(1);
 178         }
 179
 180         dindex[i] = ifidx;
 181
 182         ifr.ifr_ifindex = ifidx;
 183         if (ioctl(socket, SIOCGIFNAME, &ifr) < 0)
 184                 perror("SIOCGIFNAME");
 185
 186         if (max_devname_len < strlen(ifr.ifr_name))
 187                 max_devname_len = strlen(ifr.ifr_name);
 188
 189         strcpy(devname[i], ifr.ifr_name);
 190
 191 #ifdef DEBUG
 192         printf("new index %d (%s)\n", i, devname[i]);
 193 #endif
 194
 195         return i;
 196 }
 197
 198 int main(int argc, char **argv)
 199 {
 200         fd_set rdfs;
 201         int s[MAXSOCK];
 202         int bridge = 0;
 203         unsigned char timestamp = 0;
 204         unsigned char dropmonitor = 0;
 205         unsigned char silent = SILENT_INI;
 206         unsigned char silentani = 0;
 207         unsigned char color = 0;
 208         unsigned char view = 0;
 209         unsigned char log = 0;
 210         unsigned char logfrmt = 0;
 211         int count = 0;
 212         int rcvbuf_size = 0;
 213         int opt, ret;
 214         int currmax, numfilter;
 215         char *ptr, *nptr;
 216         struct sockaddr_can addr;
 217         char ctrlmsg[CMSG_SPACE(sizeof(struct timeval)) + CMSG_SPACE(sizeof(__u32))];
 218         struct iovec iov;
 219         struct msghdr msg;
 220         struct cmsghdr *cmsg;
 221         struct can_filter *rfilter;
 222         can_err_mask_t err_mask;
 223         struct can_frame frame;
 224         int nbytes, i;
 225         struct ifreq ifr;
 226         struct timeval tv, last_tv;
 227         FILE *logfile = NULL;
 228
 229         signal(SIGTERM, sigterm);
 230         signal(SIGHUP, sigterm);
 231         signal(SIGINT, sigterm);
 232
 233         last_tv.tv_sec  = 0;
 234         last_tv.tv_usec = 0;
 235
 236         while ((opt = getopt(argc, argv, "t:ciaSs:b:B:ldLn:r:h?")) != -1) {
 237                 switch (opt) {
 238                 case 't':
 239                         timestamp = optarg[0];
 240                         if ((timestamp != 'a') && (timestamp != 'A') &&
 241                             (timestamp != 'd') && (timestamp != 'z')) {
 242                                 fprintf(stderr, "%s: unknown timestamp mode '%c' - ignored\n",
 243                                        basename(argv[0]), optarg[0]);
 244                                 timestamp = 0;
 245                         }
 246                         break;
 247
 248                 case 'c':
 249                         color++;
 250                         break;
 251
 252                 case 'i':
 253                         view |= CANLIB_VIEW_BINARY;
 254                         break;
 255
 256                 case 'a':
 257                         view |= CANLIB_VIEW_ASCII;
 258                         break;
 259
 260                 case 'S':
 261                         view |= CANLIB_VIEW_SWAP;
 262                         break;
 263
 264                 case 's':
 265                         silent = atoi(optarg);
 266                         if (silent > SILENT_ON) {
 267                                 print_usage(basename(argv[0]));
 268                                 exit(1);
 269                         }
 270                         break;
 271
 272                 case 'b':
 273                 case 'B':
 274                         if (strlen(optarg) >= IFNAMSIZ) {
 275                                 fprintf(stderr, "Name of CAN device '%s' is too long!\n\n", optarg);
 276                                 return 1;
 277                         } else {
 278                                 bridge = socket(PF_CAN, SOCK_RAW, CAN_RAW);
 279                                 if (bridge < 0) {
 280                                         perror("bridge socket");
 281                                         return 1;
 282                                 }
 283                                 addr.can_family = AF_CAN;
 284                                 strcpy(ifr.ifr_name, optarg);
 285                                 if (ioctl(bridge, SIOCGIFINDEX, &ifr) < 0)
 286                                         perror("SIOCGIFINDEX");
 287                                 addr.can_ifindex = ifr.ifr_ifindex;
 288
 289                                 if (!addr.can_ifindex) {
 290                                         perror("invalid bridge interface");
 291                                         return 1;
 292                                 }
 293
 294                                 /* disable default receive filter on this write-only RAW socket */
 295                                 setsockopt(bridge, SOL_CAN_RAW, CAN_RAW_FILTER, NULL, 0);
 296
 297                                 if (opt == 'B') {
 298                                         const int loopback = 0;
 299
 300                                         setsockopt(bridge, SOL_CAN_RAW, CAN_RAW_LOOPBACK,
 301                                                    &loopback, sizeof(loopback));
 302                                 }
 303
 304                                 if (bind(bridge, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
 305                                         perror("bridge bind");
 306                                         return 1;
 307                                 }
 308                         }
 309                         break;
 310
 311                 case 'l':
 312                         log = 1;
 313                         break;
 314
 315                 case 'd':
 316                         dropmonitor = 1;
 317                         break;
 318
 319                 case 'L':
 320                         logfrmt = 1;
 321                         break;
 322
 323                 case 'n':
 324                         count = atoi(optarg);
 325                         if (count < 1) {
 326                                 print_usage(basename(argv[0]));
 327                                 exit(1);
 328                         }
 329                         break;
 330
 331                 case 'r':
 332                         rcvbuf_size = atoi(optarg);
 333                         if (rcvbuf_size < 1) {
 334                                 print_usage(basename(argv[0]));
 335                                 exit(1);
 336                         }
 337                         break;
 338
 339                 default:
 340                         print_usage(basename(argv[0]));
 341                         exit(1);
 342                         break;
 343                 }
 344         }
 345
 346         if (optind == argc) {
 347                 print_usage(basename(argv[0]));
 348                 exit(0);
 349         }
 350
 351         if (logfrmt && view) {
 352                 fprintf(stderr, "Log file format selected: Please disable ASCII/BINARY/SWAP options!\n");
 353                 exit(0);
 354         }
 355
 356         if (silent == SILENT_INI) {
 357                 if (log) {
 358                         fprintf(stderr, "Disabled standard output while logging.\n");
 359                         silent = SILENT_ON; /* disable output on stdout */
 360                 } else
 361                         silent = SILENT_OFF; /* default output */
 362         }
 363
 364         currmax = argc - optind; /* find real number of CAN devices */
 365
 366         if (currmax > MAXSOCK) {
 367                 fprintf(stderr, "More than %d CAN devices given on commandline!\n", MAXSOCK);
 368                 return 1;
 369         }
 370
 371         for (i=0; i < currmax; i++) {
 372
 373                 ptr = argv[optind+i];
 374                 nptr = strchr(ptr, ',');
 375
 376 #ifdef DEBUG
 377                 printf("open %d '%s'.\n", i, ptr);
 378 #endif
 379
 380                 s[i] = socket(PF_CAN, SOCK_RAW, CAN_RAW);
 381                 if (s[i] < 0) {
 382                         perror("socket");
 383                         return 1;
 384                 }
 385
 386                 cmdlinename[i] = ptr; /* save pointer to cmdline name of this socket */
 387
 388                 if (nptr)
 389                         nbytes = nptr - ptr;  /* interface name is up the first ',' */
 390                 else
 391                         nbytes = strlen(ptr); /* no ',' found => no filter definitions */
 392
 393                 if (nbytes >= IFNAMSIZ) {
 394                         fprintf(stderr, "name of CAN device '%s' is too long!\n", ptr);
 395                         return 1;
 396                 }
 397
 398                 if (nbytes > max_devname_len)
 399                         max_devname_len = nbytes; /* for nice printing */
 400
 401                 addr.can_family = AF_CAN;
 402
 403                 memset(&ifr.ifr_name, 0, sizeof(ifr.ifr_name));
 404                 strncpy(ifr.ifr_name, ptr, nbytes);
 405
 406 #ifdef DEBUG
 407                 printf("using interface name '%s'.\n", ifr.ifr_name);
 408 #endif
 409
 410                 if (strcmp(ANYDEV, ifr.ifr_name)) {
 411                         if (ioctl(s[i], SIOCGIFINDEX, &ifr) < 0) {
 412                                 perror("SIOCGIFINDEX");
 413                                 exit(1);
 414                         }
 415                         addr.can_ifindex = ifr.ifr_ifindex;
 416                 } else
 417                         addr.can_ifindex = 0; /* any can interface */
 418
 419                 if (nptr) {
 420
 421                         /* found a ',' after the interface name => check for filters */
 422
 423                         /* determine number of filters to alloc the filter space */
 424                         numfilter = 0;
 425                         ptr = nptr;
 426                         while (ptr) {
 427                                 numfilter++;
 428                                 ptr++; /* hop behind the ',' */
 429                                 ptr = strchr(ptr, ','); /* exit condition */
 430                         }
 431
 432                         rfilter = malloc(sizeof(struct can_filter) * numfilter);
 433                         if (!rfilter) {
 434                                 fprintf(stderr, "Failed to create filter space!\n");
 435                                 return 1;
 436                         }
 437
 438                         numfilter = 0;
 439                         err_mask = 0;
 440
 441                         while (nptr) {
 442
 443                                 ptr = nptr+1; /* hop behind the ',' */
 444                                 nptr = strchr(ptr, ','); /* update exit condition */
 445
 446                                 if (sscanf(ptr, "%x:%x",
 447                                            &rfilter[numfilter].can_id,
 448                                            &rfilter[numfilter].can_mask) == 2) {
 449                                         rfilter[numfilter].can_mask &= ~CAN_ERR_FLAG;
 450                                         numfilter++;
 451                                 } else if (sscanf(ptr, "%x~%x",
 452                                                   &rfilter[numfilter].can_id,
 453                                                   &rfilter[numfilter].can_mask) == 2) {
 454                                         rfilter[numfilter].can_id |= CAN_INV_FILTER;
 455                                         rfilter[numfilter].can_mask &= ~CAN_ERR_FLAG;
 456                                         numfilter++;
 457                                 } else if (sscanf(ptr, "#%x", &err_mask) != 1) {
 458                                         fprintf(stderr, "Error in filter option parsing: '%s'\n", ptr);
 459                                         return 1;
 460                                 }
 461                         }
 462
 463                         if (err_mask)
 464                                 setsockopt(s[i], SOL_CAN_RAW, CAN_RAW_ERR_FILTER,
 465                                            &err_mask, sizeof(err_mask));
 466
 467                         if (numfilter)
 468                                 setsockopt(s[i], SOL_CAN_RAW, CAN_RAW_FILTER,
 469                                            rfilter, numfilter * sizeof(struct can_filter));
 470
 471                         free(rfilter);
 472
 473                 } /* if (nptr) */
 474
 475                 if (rcvbuf_size) {
 476
 477                         int curr_rcvbuf_size;
 478                         socklen_t curr_rcvbuf_size_len = sizeof(curr_rcvbuf_size);
 479
 480                         /* try SO_RCVBUFFORCE first, if we run with CAP_NET_ADMIN */
 481                         if (setsockopt(s[i], SOL_SOCKET, SO_RCVBUFFORCE,
 482                                        &rcvbuf_size, sizeof(rcvbuf_size)) < 0) {
 483 #ifdef DEBUG
 484                                 printf("SO_RCVBUFFORCE failed so try SO_RCVBUF ...\n");
 485 #endif
 486                                 if (setsockopt(s[i], SOL_SOCKET, SO_RCVBUF,
 487                                                &rcvbuf_size, sizeof(rcvbuf_size)) < 0) {
 488                                         perror("setsockopt SO_RCVBUF");
 489                                         return 1;
 490                                 }
 491
 492                                 if (getsockopt(s[i], SOL_SOCKET, SO_RCVBUF,
 493                                                &curr_rcvbuf_size, &curr_rcvbuf_size_len) < 0) {
 494                                         perror("getsockopt SO_RCVBUF");
 495                                         return 1;
 496                                 }
 497
 498                                 /* Only print a warning the first time we detect the adjustment */
 499                                 /* n.b.: The wanted size is doubled in Linux in net/sore/sock.c */
 500                                 if (!i && curr_rcvbuf_size < rcvbuf_size*2)
 501                                         fprintf(stderr, "The socket receive buffer size was "
 502                                                 "adjusted due to /proc/sys/net/core/rmem_max.\n");
 503                         }
 504                 }
 505
 506                 if (timestamp || log || logfrmt) {
 507
 508                         const int timestamp_on = 1;
 509
 510                         if (setsockopt(s[i], SOL_SOCKET, SO_TIMESTAMP,
 511                                        &timestamp_on, sizeof(timestamp_on)) < 0) {
 512                                 perror("setsockopt SO_TIMESTAMP");
 513                                 return 1;
 514                         }
 515                 }
 516
 517                 if (dropmonitor) {
 518
 519                         const int dropmonitor_on = 1;
 520
 521                         if (setsockopt(s[i], SOL_SOCKET, SO_RXQ_OVFL,
 522                                        &dropmonitor_on, sizeof(dropmonitor_on)) < 0) {
 523                                 perror("setsockopt SO_RXQ_OVFL not supported by your Linux Kernel");
 524                                 return 1;
 525                         }
 526                 }
 527
 528                 if (bind(s[i], (struct sockaddr *)&addr, sizeof(addr)) < 0) {
 529                         perror("bind");
 530                         return 1;
 531                 }
 532         }
 533
 534         if (log) {
 535                 time_t currtime;
 536                 struct tm now;
 537                 char fname[sizeof("candump-2006-11-20_202026.log")+1];
 538
 539                 if (time(&currtime) == (time_t)-1) {
 540                         perror("time");
 541                         return 1;
 542                 }
 543
 544                 localtime_r(&currtime, &now);
 545
 546                 sprintf(fname, "candump-%04d-%02d-%02d_%02d%02d%02d.log",
 547                         now.tm_year + 1900,
 548                         now.tm_mon + 1,
 549                         now.tm_mday,
 550                         now.tm_hour,
 551                         now.tm_min,
 552                         now.tm_sec);
 553
 554                 if (silent != SILENT_ON)
 555                         printf("\nWarning: console output active while logging!");
 556
 557                 fprintf(stderr, "\nEnabling Logfile '%s'\n\n", fname);
 558
 559                 logfile = fopen(fname, "w");
 560                 if (!logfile) {
 561                         perror("logfile");
 562                         return 1;
 563                 }
 564         }
 565
 566         /* these settings are static and can be held out of the hot path */
 567         iov.iov_base = &frame;
 568         msg.msg_name = &addr;
 569         msg.msg_iov = &iov;
 570         msg.msg_iovlen = 1;
 571         msg.msg_control = &ctrlmsg;
 572
 573         while (running) {
 574
 575                 FD_ZERO(&rdfs);
 576                 for (i=0; i<currmax; i++)
 577                         FD_SET(s[i], &rdfs);
 578
 579                 if ((ret = select(s[currmax-1]+1, &rdfs, NULL, NULL, NULL)) < 0) {
 580                         //perror("select");
 581                         running = 0;
 582                         continue;
 583                 }
 584
 585                 for (i=0; i<currmax; i++) {  /* check all CAN RAW sockets */
 586
 587                         if (FD_ISSET(s[i], &rdfs)) {
 588
 589                                 int idx;
 590
 591                                 /* these settings may be modified by recvmsg() */
 592                                 iov.iov_len = sizeof(frame);
 593                                 msg.msg_namelen = sizeof(addr);
 594                                 msg.msg_controllen = sizeof(ctrlmsg);
 595                                 msg.msg_flags = 0;
 596
 597                                 nbytes = recvmsg(s[i], &msg, 0);
 598                                 if (nbytes < 0) {
 599                                         perror("read");
 600                                         return 1;
 601                                 }
 602
 603                                 if (nbytes < sizeof(struct can_frame)) {
 604                                         fprintf(stderr, "read: incomplete CAN frame\n");
 605                                         return 1;
 606                                 }
 607
 608                                 if (count && (--count == 0))
 609                                         running = 0;
 610
 611                                 if (bridge) {
 612                                         nbytes = write(bridge, &frame, sizeof(struct can_frame));
 613                                         if (nbytes < 0) {
 614                                                 perror("bridge write");
 615                                                 return 1;
 616                                         } else if (nbytes < sizeof(struct can_frame)) {
 617                                                 fprintf(stderr,"bridge write: incomplete CAN frame\n");
 618                                                 return 1;
 619                                         }
 620                                 }
 621
 622                                 for (cmsg = CMSG_FIRSTHDR(&msg);
 623                                      cmsg && (cmsg->cmsg_level == SOL_SOCKET);
 624                                      cmsg = CMSG_NXTHDR(&msg,cmsg)) {
 625                                         if (cmsg->cmsg_type == SO_TIMESTAMP)
 626                                                 tv = *(struct timeval *)CMSG_DATA(cmsg);
 627                                         else if (cmsg->cmsg_type == SO_RXQ_OVFL)
 628                                                 dropcnt[i] = *(__u32 *)CMSG_DATA(cmsg);
 629                                 }
 630
 631                                 /* check for (unlikely) dropped frames on this specific socket */
 632                                 if (dropcnt[i] != last_dropcnt[i]) {
 633
 634                                         __u32 frames;
 635
 636                                         if (dropcnt[i] > last_dropcnt[i])
 637                                                 frames = dropcnt[i] - last_dropcnt[i];
 638                                         else
 639                                                 frames = 4294967295U - last_dropcnt[i] + dropcnt[i]; /* 4294967295U == UINT32_MAX */
 640
 641                                         if (silent != SILENT_ON)
 642                                                 printf("DROPCOUNT: dropped %d CAN frame%s on '%s' socket (total drops %d)\n",
 643                                                        frames, (frames > 1)?"s":"", cmdlinename[i], dropcnt[i]);
 644
 645                                         if (log)
 646                                                 fprintf(logfile, "DROPCOUNT: dropped %d CAN frame%s on '%s' socket (total drops %d)\n",
 647                                                         frames, (frames > 1)?"s":"", cmdlinename[i], dropcnt[i]);
 648
 649                                         last_dropcnt[i] = dropcnt[i];
 650                                 }
 651
 652                                 idx = idx2dindex(addr.can_ifindex, s[i]);
 653
 654                                 if (log) {
 655                                         /* log CAN frame with absolute timestamp & device */
 656                                         fprintf(logfile, "(%ld.%06ld) ", tv.tv_sec, tv.tv_usec);
 657                                         fprintf(logfile, "%*s ", max_devname_len, devname[idx]);
 658                                         /* without seperator as logfile use-case is parsing */
 659                                         fprint_canframe(logfile, &frame, "\n", 0);
 660                                 }
 661
 662                                 if (logfrmt) {
 663                                         /* print CAN frame in log file style to stdout */
 664                                         printf("(%ld.%06ld) ", tv.tv_sec, tv.tv_usec);
 665                                         printf("%*s ", max_devname_len, devname[idx]);
 666                                         fprint_canframe(stdout, &frame, "\n", 0);
 667                                         goto out_fflush; /* no other output to stdout */
 668                                 }
 669
 670                                 if (silent != SILENT_OFF){
 671                                         if (silent == SILENT_ANI) {
 672                                                 printf("%c\b", anichar[silentani%=MAXANI]);
 673                                                 silentani++;
 674                                         }
 675                                         goto out_fflush; /* no other output to stdout */
 676                                 }
 677
 678                                 printf(" %s", (color>2)?col_on[idx%MAXCOL]:"");
 679
 680                                 switch (timestamp) {
 681
 682                                 case 'a': /* absolute with timestamp */
 683                                         printf("(%ld.%06ld) ", tv.tv_sec, tv.tv_usec);
 684                                         break;
 685
 686                                 case 'A': /* absolute with date */
 687                                 {
 688                                         struct tm tm;
 689                                         char timestring[25];
 690
 691                                         tm = *localtime(&tv.tv_sec);
 692                                         strftime(timestring, 24, "%Y-%m-%d %H:%M:%S", &tm);
 693                                         printf("(%s.%06ld) ", timestring, tv.tv_usec);
 694                                 }
 695                                 break;
 696
 697                                 case 'd': /* delta */
 698                                 case 'z': /* starting with zero */
 699                                 {
 700                                         struct timeval diff;
 701
 702                                         if (last_tv.tv_sec == 0)   /* first init */
 703                                                 last_tv = tv;
 704                                         diff.tv_sec  = tv.tv_sec  - last_tv.tv_sec;
 705                                         diff.tv_usec = tv.tv_usec - last_tv.tv_usec;
 706                                         if (diff.tv_usec < 0)
 707                                                 diff.tv_sec--, diff.tv_usec += 1000000;
 708                                         if (diff.tv_sec < 0)
 709                                                 diff.tv_sec = diff.tv_usec = 0;
 710                                         printf("(%ld.%06ld) ", diff.tv_sec, diff.tv_usec);
 711
 712                                         if (timestamp == 'd')
 713                                                 last_tv = tv; /* update for delta calculation */
 714                                 }
 715                                 break;
 716
 717                                 default: /* no timestamp output */
 718                                         break;
 719                                 }
 720
 721                                 printf(" %s", (color && (color<3))?col_on[idx%MAXCOL]:"");
 722                                 printf("%*s", max_devname_len, devname[idx]);
 723                                 printf("%s  ", (color==1)?col_off:"");
 724
 725                                 fprint_long_canframe(stdout, &frame, NULL, view);
 726
 727                                 printf("%s", (color>1)?col_off:"");
 728                                 printf("\n");
 729                         }
 730
 731                 out_fflush:
 732                         fflush(stdout);
 733                 }
 734         }
 735
 736         for (i=0; i<currmax; i++)
 737                 close(s[i]);
 738
 739         if (bridge)
 740                 close(bridge);
 741
 742         if (log)
 743                 fclose(logfile);
 744
 745         return 0;
 746 }