src/vca_canping.c

   1 /**************************************************************************/
   2 /* File: vca_canping.c - utility to test CAN functionality and throughput */
   3 /*                                                                        */
   4 /* LibVCA - Versatile CAN/CANopen API library                             */
   5 /* Copyright (C) 2005-2006 Michal Sojka, DCE FEE CTU Prague               */
   6 /* Copyright (C) 2006-2009 Pavel Pisa <pisa@cmp.felk.cvut.cz>             */
   7 /*                                                                        */
   8 /* LibVCA is free software; you can redistribute it and/or modify it      */
   9 /* under terms of the GNU General Public License as published by the      */
  10 /* Free Software Foundation; either version 2, or (at your option) any    */
  11 /* later version.  LinCAN is distributed in the hope that it will be      */
  12 /* useful, but WITHOUT ANY WARRANTY; without even the implied warranty    */
  13 /* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU    */
  14 /* General Public License for more details. You should have received a    */
  15 /* copy of the GNU General Public License along with LinCAN; see file     */
  16 /* COPYING. If not, write to the Free Software Foundation, 675 Mass Ave,  */
  17 /* Cambridge, MA 02139, USA.                                              */
  18 /**************************************************************************/
  19
  20 #include <string.h>
  21 #include <math.h>
  22 #include <stdio.h>
  23 #include <unistd.h>
  24 #include <fcntl.h>
  25 #include <stdlib.h>
  26 #include <ctype.h>
  27 #include <pthread.h>
  28 #include <signal.h>
  29 #include <sys/types.h>
  30 #include <sys/time.h>
  31 #include <ul_list.h>
  32 #include <errno.h>
  33 #include <semaphore.h>
  34 #include <stdbool.h>
  35 #include <error.h>
  36
  37 /* TODO: Handle the case where there are more canping slaves running
  38  * on one CAN bus. */
  39
  40 #include <can_vca.h>
  41
  42 //#define DEBUG 1
  43 //#define DEBUG 2
  44 #define WITH_RTPRIO
  45
  46 #ifdef WITH_RTPRIO
  47 #include <sched.h>
  48 #include <sys/mman.h>
  49
  50 int sched_policy = SCHED_OTHER;
  51 int sched_rtprio;
  52
  53 #endif
  54
  55
  56 #ifndef DEBUG
  57 #define dbg(level, fmt, arg...) do {} while (0)
  58 #else
  59 #define dbg(level, fmt, arg...) do { if (level <= DEBUG) { printf("candping: " fmt, ## arg); } } while (0)
  60 #endif
  61
  62 #define NOT_INTERRUPTED_SYSCALL (errno != EINTR && errno != ERESTART)
  63 #define IS_FINISH_FLAG() (finish_flag)
  64
  65 /* Exit codes */
  66 #define EXIT_OK 0
  67 #define EXIT_BAD_PARAM 1
  68 #define EXIT_CANNOT_OPEN 2
  69 #define EXIT_FILTER_ERROR 3
  70 #define EXIT_NO_MEM 4
  71 #define EXIT_READ_ERROR 5
  72 #define EXIT_WRITE_ERROR 6
  73 #define EXIT_SELECT_ERROR 7
  74 #define EXIT_FLUSH_ERROR 8
  75
  76 /* Global variables */
  77 sig_atomic_t finish_flag = 0;   /* Threads should terminate. */
  78 sem_t finish_sem;               /* Thread signals a termination */
  79 vca_handle_t global_vcah = VCA_HANDLE_INVALID;
  80
  81 int total_count = 0;
  82 int total_timeout = 0;
  83
  84 pthread_mutex_t mut_start = PTHREAD_MUTEX_INITIALIZER;
  85 pthread_cond_t cond_start = PTHREAD_COND_INITIALIZER;
  86 int start_flag = 0;
  87 sem_t ready_sem;                /* Thread is ready for execution */
  88
  89
  90 /* Command line options */
  91 char *option_device = "/dev/can0";
  92 int option_masters = 0;
  93 long int option_first_id = 1000;
  94 int option_slaves = 0;
  95 int option_verbose = 0;         /* 0 - nothing, 1 - only global
  96                                  * statistics, 2 - simple times, 3 -
  97                                  * verbose times */
  98 int option_length = 8;
  99 int option_count = 0;
 100 int option_wait_ms = 1000;
 101 int option_timeout = 4;
 102 int option_open_once = 0;
 103 int option_synch_start = 0;
 104 bool option_background = false;
 105 char *option_histogram = NULL;
 106
 107 /* Lists */
 108 typedef struct threads {
 109         ul_list_head_t head;
 110 } threads_t;
 111
 112 struct histogram {
 113         unsigned *data;
 114         unsigned allocated;
 115         unsigned resolution;
 116 };
 117
 118 typedef struct thread_data {
 119         pthread_t tid;
 120         long int canid;
 121
 122         int count;
 123         double mean;            /* mean value of responses */
 124         double moment2nd;       /* used to compute variance of
 125                                  * responses */
 126         int min, max;           /* min/max response times */
 127         int timeout;            /* number of timeouts */
 128
 129         struct histogram hist;
 130
 131         ul_list_node_t node;
 132 } thread_data_t;
 133
 134 UL_LIST_CUST_DEC(thread_list, threads_t, thread_data_t, head, node);
 135
 136 threads_t master_threads;
 137 threads_t slave_threads;
 138
 139 int histogram_init(struct histogram *h,
 140                    unsigned max_value,
 141                    unsigned resolution)
 142 {
 143         size_t mem;
 144         h->allocated = max_value/resolution + 1;
 145         h->resolution = resolution;
 146         mem = h->allocated*sizeof(*h->data);
 147         h->data = malloc(mem);
 148         if (h->data) {
 149                 memset(h->data, 0, mem);
 150                 return 0;
 151         } else
 152                 return -1;
 153 }
 154
 155 void histogram_add(struct histogram *h, unsigned value)
 156 {
 157         unsigned index = value / h->resolution;
 158         if (index >= h->allocated)
 159                 index = h->allocated - 1;
 160         h->data[index]++;
 161 }
 162
 163 void histogram_fprint(struct histogram *h, FILE *f)
 164 {
 165         unsigned long long sum = 0, cum;
 166         unsigned i;
 167         for (i = 0; i < h->allocated; i++)
 168                 sum += h->data[i];
 169         cum = sum;
 170         for (i = 0; i < h->allocated; i++) {
 171                 if (h->data[i] != 0)
 172                         fprintf(f, "%d %lld\n", i*h->resolution, cum);
 173                 cum -= h->data[i];
 174         }
 175 }
 176
 177 /* Subtract the `struct timeval' values X and Y, storing the result in
 178    RESULT.  Return 1 if the difference is negative, otherwise 0.  */
 179
 180 int timeval_subtract (struct timeval *result, struct timeval *x, struct timeval *y)
 181 {
 182         /* Perform the carry for the later subtraction by updating Y. */
 183         if (x->tv_usec < y->tv_usec) {
 184                 int nsec = (y->tv_usec - x->tv_usec) / 1000000 + 1;
 185                 y->tv_usec -= 1000000 * nsec;
 186                 y->tv_sec += nsec;
 187         }
 188         if (x->tv_usec - y->tv_usec > 1000000) {
 189                 int nsec = (x->tv_usec - y->tv_usec) / 1000000;
 190                 y->tv_usec += 1000000 * nsec;
 191                 y->tv_sec -= nsec;
 192         }
 193
 194         /* Compute the time remaining to wait.
 195            `tv_usec' is certainly positive. */
 196         result->tv_sec = x->tv_sec - y->tv_sec;
 197         result->tv_usec = x->tv_usec - y->tv_usec;
 198
 199         /* Return 1 if result is negative. */
 200         return x->tv_sec < y->tv_sec;
 201 }
 202
 203 void dbg_print_timeval(char *msg, struct timeval *tv)
 204 {
 205
 206         printf("%s sec=%ld usec=%ld\n", msg, tv->tv_sec, tv->tv_usec);
 207 }
 208 void kill_all_threads(int signum)
 209 {
 210         thread_data_t *td;
 211
 212         ul_list_for_each(thread_list, &master_threads, td) {
 213                 pthread_kill(td->tid, signum);
 214         }
 215         ul_list_for_each(thread_list, &slave_threads, td) {
 216                 pthread_kill(td->tid, signum);
 217         }
 218 }
 219 void term_handler(int signum)
 220 {
 221         dbg(1, "Thread %p got a signal %d\n", (void *)pthread_self(), signum);
 222         if (!IS_FINISH_FLAG()) {
 223                 dbg(1, "Terminating threads\n");
 224                 finish_flag = 1;
 225
 226                 kill_all_threads(signum);
 227         }
 228 }
 229
 230 void *master_thread(void *arg)
 231 {
 232         thread_data_t *td = (thread_data_t *)arg;
 233         int ping_id = td->canid;
 234         int pong_id = ping_id + 1;
 235         struct canmsg_t pingmsg, pongmsg;
 236         int ping_count = 0;
 237         int ret = 0;
 238         vca_handle_t vcah = VCA_HANDLE_INVALID; /* File descriptor of CAN driver. */
 239         int i;
 240         fd_set rdset;           /* read set for select syscall */
 241         struct timeval timeout, pingtime, pongtime;
 242         struct canfilt_t canfilt; /* filter for received messages */
 243
 244         if (!option_open_once) {
 245                 /* Open can driver */
 246                 if(vca_open_handle(&vcah, option_device, NULL, 0) < 0) {
 247                         perror("open");
 248                         fprintf(stderr, "Error opening %s (for id %d)\n", option_device, ping_id);
 249                         exit(EXIT_CANNOT_OPEN);
 250                 }
 251         } else {
 252                 vcah = global_vcah;
 253         }
 254
 255         /* setup filtering of received messages */
 256         memset(&canfilt, 0, sizeof(canfilt));
 257         canfilt.mask = 0xfffffff;
 258         canfilt.id = pong_id;   /* pong responces with increased id */
 259         ret = vca_set_filt(vcah, &canfilt);
 260         if(ret<0) {
 261                 perror("ioctl CANQUE_FILTER");
 262                 exit(EXIT_FILTER_ERROR);
 263         }
 264         ret = vca_queue_flush(vcah, 0);
 265         if(ret<0) {
 266                 perror("ioctl CANQUE_QUEUE_FLUSH");
 267                 exit(EXIT_FLUSH_ERROR);
 268         }
 269
 270         if (option_histogram)
 271                 histogram_init(&td->hist, 1000*1000/*max [us]*/, 5/*resolution [us]*/);
 272
 273         /* Prepare data structures for the select syscall. */
 274         FD_ZERO (&rdset);
 275
 276         /* Signal that I'm ready */
 277         sem_post(&ready_sem);
 278
 279         if (option_synch_start) {
 280                 /* Wait for other threads to initialize */
 281                 pthread_mutex_lock(&mut_start);
 282                 while (!start_flag) pthread_cond_wait(&cond_start, &mut_start);
 283                 pthread_mutex_unlock(&mut_start);
 284         }
 285
 286         while (!IS_FINISH_FLAG() && (option_count == 0 || ping_count++ < option_count)) {
 287                 /* Send a ping message */
 288                 pingmsg.flags=0;
 289                 pingmsg.id=ping_id;
 290                 pingmsg.length = option_length;
 291                 for (i=0; i < option_length; i++) pingmsg.data[i] = i;
 292                 gettimeofday(&pingtime, NULL);
 293
 294                 ret = vca_send_msg_seq(vcah, &pingmsg, 1);
 295                 if (ret < 0) {
 296                         if (NOT_INTERRUPTED_SYSCALL) {
 297                                 perror("write");
 298                                 exit(EXIT_WRITE_ERROR);
 299                         }
 300                         else continue;
 301                 }
 302
 303                 /* Wait for a pong responce */
 304                 FD_SET (vca_h2fd(vcah), &rdset);
 305
 306                 timeout.tv_sec = option_timeout;
 307                 timeout.tv_usec = 0;
 308
 309                 ret = select(FD_SETSIZE, &rdset, NULL, NULL, &timeout);
 310                 if (ret > 0) {
 311                         /* Read the message */
 312                         pongmsg.flags=0;
 313                         ret = vca_rec_msg_seq(vcah, &pongmsg, 1);
 314                         if (ret < 0) {
 315                                 if (NOT_INTERRUPTED_SYSCALL) {
 316                                         perror("read");
 317                                         exit(EXIT_READ_ERROR);
 318                                 }
 319                                 else continue;
 320                         }
 321                         else {  /* A pong message received */
 322                                 long int time;
 323                                 gettimeofday(&pongtime, NULL);
 324                                 if (ret == 0) {
 325                                         fprintf(stderr, "read returned zero\n");
 326                                         exit(EXIT_READ_ERROR);
 327                                 }
 328                                 if (pongmsg.id != pong_id) {
 329                                         fprintf(stderr, "Filter error (expected: %d, received %ld)\n", pong_id, pongmsg.id);
 330                                         exit(EXIT_FILTER_ERROR);
 331                                 }
 332                                 timeval_subtract(&pongtime, &pongtime, &pingtime);
 333                                 time = pongtime.tv_sec*1000000 + pongtime.tv_usec;
 334                                 switch (option_verbose) {
 335                                 case 2:
 336                                         printf("%d:%ld\n", ping_id, time);
 337                                         break;
 338                                 case 3:
 339                                         printf("Pong response for id %d received in %ld us\n", ping_id, time);
 340                                         break;
 341                                 }
 342                                 /* Update statistics */
 343                                 td->count++;
 344                                 td->mean =
 345                                         td->mean * ((double)(td->count - 1) / td->count) +
 346                                         (double)time / td->count;
 347                                 td->moment2nd =
 348                                         td->moment2nd * ((double)(td->count - 1) / td->count) +
 349                                         (double)time*time  / td->count;
 350                                 if (time > td->max) td->max = time;
 351                                 if (time < td->min) td->min = time;
 352                                 if (option_histogram)
 353                                         histogram_add(&td->hist, time);
 354                                 total_count++;
 355                         } /* read */
 356                 }
 357                 else if (ret == 0) { /* select */
 358                         if (option_verbose >= 2)
 359                                 printf("Timeout encountered (id %d)\n", ping_id);
 360                         td->timeout++;
 361                         total_timeout++;
 362                 }
 363                 else {
 364                         if (NOT_INTERRUPTED_SYSCALL) {
 365                                 perror("select");
 366                                 exit(EXIT_SELECT_ERROR);
 367                         }
 368                         else continue;
 369                 }
 370                 usleep(option_wait_ms * 1000);
 371         }
 372
 373         if (!option_open_once) {
 374                 /* Close the can driver */
 375                 vca_close_handle(vcah);
 376         }
 377
 378         if (option_histogram) {
 379                 FILE *f;
 380                 char buf[100];
 381                 snprintf(buf, sizeof(buf), "%s-%d.dat", option_histogram, ping_id);
 382                 f = fopen(buf, "w");
 383                 histogram_fprint(&td->hist, f);
 384                 fclose(f);
 385         }
 386
 387         sem_post(&finish_sem);
 388         return (void *)ret;
 389 }
 390
 391 void start_masters(int masters, int first_id)
 392 {
 393         int id = first_id;
 394         int i;
 395
 396         dbg(1, "Starting %d master threads\n", masters);
 397
 398         for (i = 0; i < masters; i++, id += 2) {
 399                 thread_data_t *td;
 400
 401                 td = malloc(sizeof(*td));
 402                 if (!td) {
 403                         printf("Can't allocate memory");
 404                         exit(EXIT_NO_MEM);
 405                 }
 406                 memset(td, 0, sizeof(*td));
 407                 td->canid = id;
 408                 td->min = 0x7fffffff;
 409                 /* TODO use mutexes and signal blocking */
 410                 thread_list_ins_tail(&master_threads, td);
 411                 pthread_create(&td->tid, NULL, master_thread, (void *)td);
 412                 dbg(2, "Master thread: %p\n", (void *)td->tid);
 413         }
 414
 415
 416         /* Wait for all threads beeing ready */
 417         for (i = 0; i < masters; i++) sem_wait(&ready_sem);
 418
 419         /* Start threads */
 420         pthread_mutex_lock(&mut_start);
 421         start_flag = 1;
 422         pthread_cond_broadcast(&cond_start);
 423         pthread_mutex_unlock(&mut_start);
 424 }
 425
 426 void *slave_thread(void *arg)
 427 {
 428         thread_data_t *td = (thread_data_t *)arg;
 429         int ping_id = td->canid;
 430         int pong_id = ping_id + 1;
 431         struct canmsg_t pingmsg, pongmsg;
 432         int ret = 0;
 433         vca_handle_t vcah = VCA_HANDLE_INVALID; /* File descriptor of CAN driver. */
 434         int i;
 435         struct canfilt_t canfilt; /* filter for received messages */
 436
 437         if (!option_open_once) {
 438                 /* Open the CAN driver */
 439                 if(vca_open_handle(&vcah, option_device, NULL, 0) < 0) {
 440                         perror("open");
 441                         printf("Error opening %s (for id %d)\n", option_device, ping_id);
 442                         exit(EXIT_CANNOT_OPEN);
 443                 }
 444         } else {
 445                 vcah = global_vcah;
 446         }
 447
 448         /* setup filtering of received messages */
 449         memset(&canfilt, 0, sizeof(canfilt));
 450         canfilt.mask = 0xfffffff;
 451         canfilt.id = ping_id;   /* receive only our ping messages */
 452         ret = vca_set_filt(vcah, &canfilt);
 453         if (ret < 0) {
 454                 perror("ioctl CANQUE_FILTER");
 455                 exit(EXIT_FILTER_ERROR);
 456         }
 457         /* If there are some messages already, delete them. These may
 458          * not processed by our filter and thus may have a wrong
 459          * ID. */
 460         ret = vca_queue_flush(vcah, 0);
 461         if (ret < 0) {
 462                 perror("ioctl CANQUE_QUEUE_FLUSH");
 463                 exit(EXIT_FLUSH_ERROR);
 464         }
 465
 466         /* Prepare a pong message */
 467         pongmsg.flags = 0;
 468         pongmsg.id = pong_id;
 469         pongmsg.length = option_length;
 470         for (i=0; i < option_length; i++) pongmsg.data[i] = i;
 471
 472         /* Signal that I'm ready */
 473         sem_post(&ready_sem);
 474
 475         while (!IS_FINISH_FLAG()) {
 476                 /* Receive a ping message */
 477                 pingmsg.flags=0;
 478                 ret = vca_rec_msg_seq(vcah, &pingmsg, 1);
 479                 if (ret < 0) {
 480                         if (NOT_INTERRUPTED_SYSCALL) {
 481                                 printf("%d\n", errno);
 482                                 perror("read");
 483                                 exit(EXIT_READ_ERROR);
 484                         }
 485                 }
 486                 if (NOT_INTERRUPTED_SYSCALL && pingmsg.id != ping_id) {
 487                         fprintf(stderr, "Filter error (expected: %d, received %ld)\n", ping_id, pingmsg.id);
 488                         exit(EXIT_FILTER_ERROR);
 489                 }
 490                 /* Answer immendiately with a pong message */
 491                 if (NOT_INTERRUPTED_SYSCALL) {
 492                         ret = vca_send_msg_seq(vcah, &pongmsg, 1);
 493                         if (ret < 0) {
 494                                 if (NOT_INTERRUPTED_SYSCALL) {
 495                                         perror("write");
 496                                         exit(EXIT_WRITE_ERROR);
 497                                 }
 498                         }
 499                 }
 500
 501                 if (ret >= 0) total_count++;
 502
 503                 if (option_verbose >= 2)
 504                         /* This drasticly slows down the pong
 505                          * response. Why??? */
 506                         printf("Replying to ping id %lu\n", pingmsg.id);
 507
 508         }
 509
 510         if (!option_open_once) {
 511                 /* Close can driver */
 512                 vca_close_handle(vcah);
 513         }
 514
 515         dbg(2, "Slave thread for id %d is going to finish\n", ping_id);
 516
 517         sem_post(&finish_sem);
 518         return (void *)ret;
 519 }
 520
 521 void start_slaves(int slaves, int first_id)
 522 {
 523         int id = first_id;
 524         int i;
 525
 526         dbg(1, "Starting %d slave threads\n", slaves);
 527
 528         for (i = 0; i < slaves; i++, id += 2) {
 529                 thread_data_t *td;
 530
 531                 td = malloc(sizeof(*td));
 532                 if (!td) {
 533                         printf("Can't allocate memory");
 534                         exit(EXIT_NO_MEM);
 535                 }
 536                 memset(td, 0, sizeof(*td));
 537                 td->canid = id;
 538                 /* TODO use mutexes and signal blocking */
 539                 thread_list_ins_tail(&slave_threads, td);
 540                 pthread_create(&td->tid, NULL, slave_thread, (void *)td);
 541                 dbg(2, "Slave thread: %p\n", (void *)td->tid);
 542         }
 543
 544         /* Wait for all threads beeing ready */
 545         for (i = 0; i < slaves; i++) sem_wait(&ready_sem);
 546 }
 547
 548 #ifdef WITH_RTPRIO
 549 int set_sched_policy_and_prio(int policy, int rtprio)
 550 {
 551         struct sched_param scheduling_parameters;
 552         int maxprio=sched_get_priority_max(policy);
 553         int minprio=sched_get_priority_min(policy);
 554
 555         if((rtprio < minprio) || (rtprio > maxprio)) {
 556                 fprintf(stderr, "The priority for requested policy is out of <%d, %d> range\n",
 557                                 minprio, maxprio);
 558                 return -1;
 559         }
 560
 561         scheduling_parameters.sched_priority = rtprio;
 562
 563         if (0 != pthread_setschedparam(pthread_self(), policy, &scheduling_parameters)) {
 564                 perror("pthread_setschedparam error");
 565         }
 566         return 0;
 567 }
 568 #endif
 569
 570 void print_help(void)
 571 {
 572         printf("Usage: canping -m <master threads> [other options]\n"
 573                "       canping -s <slave threads> [other options]\n\n"
 574                "Other options:\n"
 575                "  -b            go to background (fork) after initialization, prints child PID\n"
 576                "  -c count      how many messages each master sends\n"
 577                "  -d dev        device (e.g. /dev/can1)\n"
 578                "  -g prefix     store cumulative histogram in file <prefix>-<id>.dat\n"
 579                "  -h            print this help\n"
 580                "  -i id         id of first master message\n"
 581                "  -l length     length of the messages (0..8)\n"
 582                "  -o            open a device only once for all threads (doesn't work)\n" /* due to filters */
 583                "  -t timeout    timeout in seconds (default 4 s)\n"
 584                "  -v            be verbose (use more than once to increase verbosity)\n"
 585                "  -w ms         wait ms miliseconds between sending pings\n"
 586                "  -y            synchronize threads before start (doesn't test race conditions\n"
 587                "                between open and read/write)\n"
 588 #ifdef WITH_RTPRIO
 589                "  -r            run at realtime priority\n"
 590                "  -R P:prio     run at realtime priority prio, policy RR or FF\n"
 591 #endif
 592                "\n"
 593                "Example: canping -m 10 -vv\n"
 594                 );
 595 }
 596
 597 int parse_options(int argc, char *argv[])
 598 {
 599         int c;
 600
 601         opterr = 0;
 602         while ((c = getopt (argc, argv, "bc:d:g:h:i:l:m:os:t:vw:yrR:")) != -1)
 603                 switch (c)
 604                 {
 605                 case 'b':
 606                         option_background = true;
 607                         break;
 608                 case 'c':
 609                         option_count = atoi(optarg);
 610                         break;
 611                 case 'd':
 612                         option_device = optarg;
 613                         break;
 614                 case 'g':
 615                         option_histogram = optarg;
 616                         break;
 617                 case 'h':
 618                         print_help();
 619                         exit(EXIT_OK);
 620                         break;
 621                 case 'i':
 622                         option_first_id = atoi(optarg);
 623                         break;
 624                 case 'l':
 625                         option_length = atoi(optarg);
 626                         if (option_length > 8) option_length = 8;
 627                         if (option_length < 0) option_length = 0;
 628                         break;
 629                 case 'm':
 630                         option_masters = atoi(optarg);
 631                         break;
 632                 case 'o':
 633                         option_open_once = 1;
 634                         break;
 635                 case 's':
 636                         option_slaves = atoi(optarg);
 637                         break;
 638                 case 't':
 639                         option_timeout = atoi(optarg);
 640                         break;
 641                 case 'v':
 642                         option_verbose++;
 643                         break;
 644                 case 'w':
 645                         option_wait_ms = atoi(optarg);
 646                         break;
 647                 case 'y':
 648                         option_synch_start = 1;
 649                         break;
 650 #ifdef WITH_RTPRIO
 651                 case 'r':
 652                         sched_policy = SCHED_FIFO;
 653                         sched_rtprio = (sched_get_priority_min(SCHED_FIFO) +
 654                                         sched_get_priority_max(SCHED_FIFO)) / 2;
 655                         break;
 656                 case 'R':
 657                         if(!isalpha(*optarg)) {
 658                                 sched_policy = SCHED_FIFO;
 659                         } else if(!strncmp(optarg,"FF:",3)) {
 660                                 sched_policy = SCHED_FIFO;
 661                                 optarg += 3;
 662                         } else if(!strncmp(optarg,"RR:",3)) {
 663                                 sched_policy = SCHED_RR;
 664                                 optarg += 3;
 665                         } else {
 666                                 fprintf (stderr, "Unknown policy %s\n", optarg);
 667                                 exit(EXIT_BAD_PARAM);
 668                         }
 669                         sched_rtprio = atoi(optarg);
 670                         break;
 671 #endif
 672                 case '?':
 673                         if (isprint (optopt))
 674                                 fprintf (stderr, "Unknown option `-%c'.\n", optopt);
 675                         else
 676                                 fprintf (stderr,
 677                                          "Unknown option character `\\x%x'.\n",
 678                                          optopt);
 679                         return 1;
 680                 default:
 681                         exit(EXIT_BAD_PARAM);
 682                 }
 683         if (!(option_masters || option_slaves) || (option_masters && option_slaves))
 684                 exit(EXIT_BAD_PARAM);
 685         return 0;
 686 }
 687
 688 void print_stats(thread_data_t *td)
 689 {
 690         char std[20];
 691         int count = td->count + td->timeout;
 692
 693         if (td->count >= 2) {
 694                 snprintf(std, 19, "%7.2f", sqrt((td->count/(td->count - 1)) *
 695                                                 (td->moment2nd - td->mean*td->mean)));
 696         } else {
 697                 strncpy(std, "N/A", 19);
 698         }
 699         printf("Id %4ld: count = %5d"
 700                " mean = %7.2f stddev = %s"
 701                " min = %5d max = %5d [us]"
 702                " loss = %d%% (%d)\n",
 703                td->canid, count, td->mean,
 704                std,
 705                td->min, td->max,
 706                (count > 0) ? 100 * td->timeout / count : 0, td->timeout
 707                 );
 708 }
 709
 710 void wait_for_threads(void)
 711 {
 712         thread_data_t *td;
 713         void *thread_ret;
 714         int thread_count = option_slaves + option_masters;
 715         int ret;
 716
 717         while (thread_count > 0) {
 718                 if (option_verbose != 1) {
 719                         ret = sem_wait(&finish_sem);
 720                         dbg(2, "Main thread sem_wait() exited with ret=%d.\n", ret);
 721
 722                         /* If the sem_wait is successful i.e. not
 723                          * interrupted by a signal, decrease the
 724                          * thread_count*/
 725                         if (ret == 0) thread_count--;
 726                 } else {
 727                         if (!IS_FINISH_FLAG()) {
 728                                 printf("Total count: %6d, Timeouts: %6d\r", total_count, total_timeout);
 729                                 fflush(stdout);
 730                                 usleep(1000000);
 731                         }
 732                         while (sem_trywait(&finish_sem) == 0) thread_count--;
 733                 }
 734         }
 735         if (option_verbose == 1) {
 736                 printf("\n");
 737         }
 738
 739         ul_list_for_each(thread_list, &master_threads, td) {
 740                 pthread_join(td->tid, &thread_ret);
 741                 dbg(2, "Master thread for id %ld finished; exit code %d\n", td->canid, (int)thread_ret);
 742         }
 743
 744         ul_list_for_each(thread_list, &slave_threads, td) {
 745                 pthread_join(td->tid, &thread_ret);
 746                 dbg(2, "Slave thread for id %ld finished; exit code %d\n", td->canid, (int)thread_ret);
 747         }
 748
 749         if (option_masters) printf("Summary statistics:\n");
 750
 751         ul_list_for_each_cut(thread_list, &master_threads, td) {
 752                 print_stats(td);
 753                 free(td);
 754         }
 755
 756
 757         ul_list_for_each_cut(thread_list, &slave_threads, td)
 758                 free(td);
 759 }
 760
 761 int main(int argc, char *argv[])
 762 {
 763         parse_options(argc, argv);
 764
 765 #ifdef WITH_RTPRIO
 766         if(sched_policy != SCHED_OTHER) {
 767                 if(set_sched_policy_and_prio(sched_policy, sched_rtprio) <0)
 768                         exit(EXIT_BAD_PARAM);
 769                 mlockall(MCL_CURRENT | MCL_FUTURE);
 770         }
 771 #endif
 772
 773
 774         thread_list_init_head(&master_threads);
 775         thread_list_init_head(&slave_threads);
 776
 777         sem_init(&finish_sem, 0, 0);
 778         sem_init(&ready_sem, 0, 0);
 779
 780         siginterrupt(SIGINT, 1);
 781         signal(SIGINT, term_handler);
 782         siginterrupt(SIGTERM, 1);
 783         signal(SIGTERM, term_handler);
 784
 785         dbg(2, "Main thread: %p\n", (void *)pthread_self());
 786
 787         if (option_open_once) {
 788                 /* Open the CAN driver */
 789                 if(vca_open_handle(&global_vcah, option_device, NULL, 0) < 0) {
 790                         perror("open");
 791                         printf("Error opening %s\n", option_device);
 792                         exit(EXIT_CANNOT_OPEN);
 793                 }
 794         }
 795
 796         sem_t *child_ready;
 797         int fork_ret = 0;
 798         if ((child_ready = sem_open("canping", O_CREAT)) == NULL)
 799                 error(1, errno, "sem_open");
 800         if (option_background) {
 801                 /* Go to background when everything is ready */
 802                 fork_ret = fork();
 803                 if (fork_ret < 0)
 804                         error(1, errno, "Cannot go to background");
 805                 if (fork_ret == 0) {
 806                         int devnull = open("/dev/null", O_WRONLY);
 807                         dup2(devnull, 1);
 808                 }
 809         }
 810
 811         if (fork_ret == 0) {
 812                 /* Child */
 813                 if (option_masters) start_masters(option_masters, option_first_id);
 814                 if (option_slaves) start_slaves(option_slaves, option_first_id);
 815                 sem_post(child_ready);
 816         } else {
 817                 /* Parent */
 818                 sem_wait(child_ready);
 819                 printf("%d\n", fork_ret);
 820                 exit(0);
 821         }
 822
 823         wait_for_threads();
 824
 825         if (option_open_once) {
 826                 vca_close_handle(global_vcah);
 827         }
 828
 829         return 0;
 830 }