1 /* 2 * ifstat.c handy utility to read net interface statistics 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 * 9 * Authors: Alexey Kuznetsov, <kuznet (at) ms2.inr.ac.ru> 10 */ 11 12 #include <stdio.h> 13 #include <stdlib.h> 14 #include <unistd.h> 15 #include <fcntl.h> 16 #include <string.h> 17 #include <errno.h> 18 #include <time.h> 19 #include <sys/time.h> 20 #include <fnmatch.h> 21 #include <sys/file.h> 22 #include <sys/socket.h> 23 #include <sys/un.h> 24 #include <sys/poll.h> 25 #include <sys/wait.h> 26 #include <sys/stat.h> 27 #include <signal.h> 28 #include <math.h> 29 #include <getopt.h> 30 31 #include <libnetlink.h> 32 #include <linux/netdevice.h> 33 34 #include <SNAPSHOT.h> 35 36 int dump_zeros = 0; 37 int reset_history = 0; 38 int ignore_history = 0; 39 int no_output = 0; 40 int no_update = 0; 41 int scan_interval = 0; 42 int time_constant = 0; 43 int show_errors = 0; 44 double W; 45 char **patterns; 46 int npatterns; 47 48 char info_source[128]; 49 int source_mismatch; 50 51 #define MAXS (sizeof(struct net_device_stats)/sizeof(unsigned long)) 52 53 struct ifstat_ent 54 { 55 struct ifstat_ent *next; 56 char *name; 57 int ifindex; 58 unsigned long long val[MAXS]; 59 double rate[MAXS]; 60 unsigned long ival[MAXS]; 61 }; 62 63 struct ifstat_ent *kern_db; 64 struct ifstat_ent *hist_db; 65 66 static int match(const char *id) 67 { 68 int i; 69 70 if (npatterns == 0) 71 return 1; 72 73 for (i=0; i<npatterns; i++) { 74 if (!fnmatch(patterns[i], id, 0)) 75 return 1; 76 } 77 return 0; 78 } 79 80 static int get_nlmsg(const struct sockaddr_nl *who, 81 struct nlmsghdr *m, void *arg) 82 { 83 struct ifinfomsg *ifi = NLMSG_DATA(m); 84 struct rtattr * tb[IFLA_MAX+1]; 85 int len = m->nlmsg_len; 86 struct ifstat_ent *n; 87 int i; 88 89 if (m->nlmsg_type != RTM_NEWLINK) 90 return 0; 91 92 len -= NLMSG_LENGTH(sizeof(*ifi)); 93 if (len < 0) 94 return -1; 95 96 if (!(ifi->ifi_flags&IFF_UP)) 97 return 0; 98 99 parse_rtattr(tb, IFLA_MAX, IFLA_RTA(ifi), len); 100 if (tb[IFLA_IFNAME] == NULL || tb[IFLA_STATS] == NULL) 101 return 0; 102 103 n = malloc(sizeof(*n)); 104 if (!n) 105 abort(); 106 n->ifindex = ifi->ifi_index; 107 n->name = strdup(RTA_DATA(tb[IFLA_IFNAME])); 108 memcpy(&n->ival, RTA_DATA(tb[IFLA_STATS]), sizeof(n->ival)); 109 memset(&n->rate, 0, sizeof(n->rate)); 110 for (i=0; i<MAXS; i++) 111 n->val[i] = n->ival[i]; 112 n->next = kern_db; 113 kern_db = n; 114 return 0; 115 } 116 117 void load_info(void) 118 { 119 struct ifstat_ent *db, *n; 120 struct rtnl_handle rth; 121 122 if (rtnl_open(&rth, 0) < 0) 123 exit(1); 124 125 if (rtnl_wilddump_request(&rth, AF_INET, RTM_GETLINK) < 0) { 126 perror("Cannot send dump request"); 127 exit(1); 128 } 129 130 if (rtnl_dump_filter(&rth, get_nlmsg, NULL, NULL, NULL) < 0) { 131 fprintf(stderr, "Dump terminated\n"); 132 exit(1); 133 } 134 135 rtnl_close(&rth); 136 137 db = kern_db; 138 kern_db = NULL; 139 140 while (db) { 141 n = db; 142 db = db->next; 143 n->next = kern_db; 144 kern_db = n; 145 } 146 } 147 148 void load_raw_table(FILE *fp) 149 { 150 char buf[4096]; 151 struct ifstat_ent *db = NULL; 152 struct ifstat_ent *n; 153 154 while (fgets(buf, sizeof(buf), fp) != NULL) { 155 char *p; 156 char *next; 157 int i; 158 159 if (buf[0] == '#') { 160 buf[strlen(buf)-1] = 0; 161 if (info_source[0] && strcmp(info_source, buf+1)) 162 source_mismatch = 1; 163 strncpy(info_source, buf+1, sizeof(info_source)-1); 164 continue; 165 } 166 if ((n = malloc(sizeof(*n))) == NULL) 167 abort(); 168 169 if (!(p = strchr(buf, ' '))) 170 abort(); 171 *p++ = 0; 172 173 if (sscanf(buf, "%d", &n->ifindex) != 1) 174 abort(); 175 if (!(next = strchr(p, ' '))) 176 abort(); 177 *next++ = 0; 178 179 n->name = strdup(p); 180 p = next; 181 182 for (i=0; i<MAXS; i++) { 183 unsigned rate; 184 if (!(next = strchr(p, ' '))) 185 abort(); 186 *next++ = 0; 187 if (sscanf(p, "%llu", n->val+i) != 1) 188 abort(); 189 n->ival[i] = (unsigned long)n->val[i]; 190 p = next; 191 if (!(next = strchr(p, ' '))) 192 abort(); 193 *next++ = 0; 194 if (sscanf(p, "%u", &rate) != 1) 195 abort(); 196 n->rate[i] = rate; 197 p = next; 198 } 199 n->next = db; 200 db = n; 201 } 202 203 while (db) { 204 n = db; 205 db = db->next; 206 n->next = kern_db; 207 kern_db = n; 208 } 209 } 210 211 void dump_raw_db(FILE *fp, int to_hist) 212 { 213 struct ifstat_ent *n, *h; 214 h = hist_db; 215 fprintf(fp, "#%s\n", info_source); 216 217 for (n=kern_db; n; n=n->next) { 218 int i; 219 unsigned long long *vals = n->val; 220 double *rates = n->rate; 221 if (!match(n->name)) { 222 struct ifstat_ent *h1; 223 if (!to_hist) 224 continue; 225 for (h1 = h; h1; h1 = h1->next) { 226 if (h1->ifindex == n->ifindex) { 227 vals = h1->val; 228 rates = h1->rate; 229 h = h1->next; 230 break; 231 } 232 } 233 } 234 fprintf(fp, "%d %s ", n->ifindex, n->name); 235 for (i=0; i<MAXS; i++) 236 fprintf(fp, "%llu %u ", vals[i], (unsigned)rates[i]); 237 fprintf(fp, "\n"); 238 } 239 } 240 241 /* use communication definitions of meg/kilo etc */ 242 static const unsigned long long giga = 1000000000ull; 243 static const unsigned long long mega = 1000000; 244 static const unsigned long long kilo = 1000; 245 246 void format_rate(FILE *fp, unsigned long long *vals, double *rates, int i) 247 { 248 char temp[64]; 249 if (vals[i] > giga) 250 fprintf(fp, "%7lluM ", vals[i]/mega); 251 else if (vals[i] > mega) 252 fprintf(fp, "%7lluK ", vals[i]/kilo); 253 else 254 fprintf(fp, "%8llu ", vals[i]); 255 256 if (rates[i] > mega) { 257 sprintf(temp, "%uM", (unsigned)(rates[i]/mega)); 258 fprintf(fp, "%-6s ", temp); 259 } else if (rates[i] > kilo) { 260 sprintf(temp, "%uK", (unsigned)(rates[i]/kilo)); 261 fprintf(fp, "%-6s ", temp); 262 } else 263 fprintf(fp, "%-6u ", (unsigned)rates[i]); 264 } 265 266 void format_pair(FILE *fp, unsigned long long *vals, int i, int k) 267 { 268 char temp[64]; 269 if (vals[i] > giga) 270 fprintf(fp, "%7lluM ", vals[i]/mega); 271 else if (vals[i] > mega) 272 fprintf(fp, "%7lluK ", vals[i]/kilo); 273 else 274 fprintf(fp, "%8llu ", vals[i]); 275 276 if (vals[k] > giga) { 277 sprintf(temp, "%uM", (unsigned)(vals[k]/mega)); 278 fprintf(fp, "%-6s ", temp); 279 } else if (vals[k] > mega) { 280 sprintf(temp, "%uK", (unsigned)(vals[k]/kilo)); 281 fprintf(fp, "%-6s ", temp); 282 } else 283 fprintf(fp, "%-6u ", (unsigned)vals[k]); 284 } 285 286 void print_head(FILE *fp) 287 { 288 fprintf(fp, "#%s\n", info_source); 289 fprintf(fp, "%-15s ", "Interface"); 290 291 fprintf(fp, "%8s/%-6s ", "RX Pkts", "Rate"); 292 fprintf(fp, "%8s/%-6s ", "TX Pkts", "Rate"); 293 fprintf(fp, "%8s/%-6s ", "RX Data", "Rate"); 294 fprintf(fp, "%8s/%-6s\n","TX Data", "Rate"); 295 296 if (!show_errors) { 297 fprintf(fp, "%-15s ", ""); 298 fprintf(fp, "%8s/%-6s ", "RX Errs", "Drop"); 299 fprintf(fp, "%8s/%-6s ", "TX Errs", "Drop"); 300 fprintf(fp, "%8s/%-6s ", "RX Over", "Rate"); 301 fprintf(fp, "%8s/%-6s\n","TX Coll", "Rate"); 302 } else { 303 fprintf(fp, "%-15s ", ""); 304 fprintf(fp, "%8s/%-6s ", "RX Errs", "Rate"); 305 fprintf(fp, "%8s/%-6s ", "RX Drop", "Rate"); 306 fprintf(fp, "%8s/%-6s ", "RX Over", "Rate"); 307 fprintf(fp, "%8s/%-6s\n","RX Leng", "Rate"); 308 309 fprintf(fp, "%-15s ", ""); 310 fprintf(fp, "%8s/%-6s ", "RX Crc", "Rate"); 311 fprintf(fp, "%8s/%-6s ", "RX Frm", "Rate"); 312 fprintf(fp, "%8s/%-6s ", "RX Fifo", "Rate"); 313 fprintf(fp, "%8s/%-6s\n","RX Miss", "Rate"); 314 315 fprintf(fp, "%-15s ", ""); 316 fprintf(fp, "%8s/%-6s ", "TX Errs", "Rate"); 317 fprintf(fp, "%8s/%-6s ", "TX Drop", "Rate"); 318 fprintf(fp, "%8s/%-6s ", "TX Coll", "Rate"); 319 fprintf(fp, "%8s/%-6s\n","TX Carr", "Rate"); 320 321 fprintf(fp, "%-15s ", ""); 322 fprintf(fp, "%8s/%-6s ", "TX Abrt", "Rate"); 323 fprintf(fp, "%8s/%-6s ", "TX Fifo", "Rate"); 324 fprintf(fp, "%8s/%-6s ", "TX Hear", "Rate"); 325 fprintf(fp, "%8s/%-6s\n","TX Wind", "Rate"); 326 } 327 } 328 329 void print_one_if(FILE *fp, struct ifstat_ent *n, unsigned long long *vals) 330 { 331 int i; 332 fprintf(fp, "%-15s ", n->name); 333 for (i=0; i<4; i++) 334 format_rate(fp, vals, n->rate, i); 335 fprintf(fp, "\n"); 336 337 if (!show_errors) { 338 fprintf(fp, "%-15s ", ""); 339 format_pair(fp, vals, 4, 6); 340 format_pair(fp, vals, 5, 7); 341 format_rate(fp, vals, n->rate, 11); 342 format_rate(fp, vals, n->rate, 9); 343 fprintf(fp, "\n"); 344 } else { 345 fprintf(fp, "%-15s ", ""); 346 format_rate(fp, vals, n->rate, 4); 347 format_rate(fp, vals, n->rate, 6); 348 format_rate(fp, vals, n->rate, 11); 349 format_rate(fp, vals, n->rate, 10); 350 fprintf(fp, "\n"); 351 352 fprintf(fp, "%-15s ", ""); 353 format_rate(fp, vals, n->rate, 12); 354 format_rate(fp, vals, n->rate, 13); 355 format_rate(fp, vals, n->rate, 14); 356 format_rate(fp, vals, n->rate, 15); 357 fprintf(fp, "\n"); 358 359 fprintf(fp, "%-15s ", ""); 360 format_rate(fp, vals, n->rate, 5); 361 format_rate(fp, vals, n->rate, 7); 362 format_rate(fp, vals, n->rate, 9); 363 format_rate(fp, vals, n->rate, 17); 364 fprintf(fp, "\n"); 365 366 fprintf(fp, "%-15s ", ""); 367 format_rate(fp, vals, n->rate, 16); 368 format_rate(fp, vals, n->rate, 18); 369 format_rate(fp, vals, n->rate, 19); 370 format_rate(fp, vals, n->rate, 20); 371 fprintf(fp, "\n"); 372 } 373 } 374 375 376 void dump_kern_db(FILE *fp) 377 { 378 struct ifstat_ent *n, *h; 379 h = hist_db; 380 381 print_head(fp); 382 383 for (n=kern_db; n; n=n->next) { 384 if (!match(n->name)) 385 continue; 386 print_one_if(fp, n, n->val); 387 } 388 } 389 390 391 void dump_incr_db(FILE *fp) 392 { 393 struct ifstat_ent *n, *h; 394 h = hist_db; 395 396 print_head(fp); 397 398 for (n=kern_db; n; n=n->next) { 399 int i; 400 unsigned long long vals[MAXS]; 401 struct ifstat_ent *h1; 402 403 memcpy(vals, n->val, sizeof(vals)); 404 405 for (h1 = h; h1; h1 = h1->next) { 406 if (h1->ifindex == n->ifindex) { 407 for (i = 0; i < MAXS; i++) 408 vals[i] -= h1->val[i]; 409 h = h1->next; 410 break; 411 } 412 } 413 if (!match(n->name)) 414 continue; 415 print_one_if(fp, n, vals); 416 } 417 } 418 419 420 static int children; 421 422 void sigchild(int signo) 423 { 424 } 425 426 void update_db(int interval) 427 { 428 struct ifstat_ent *n, *h; 429 430 n = kern_db; 431 kern_db = NULL; 432 433 load_info(); 434 435 h = kern_db; 436 kern_db = n; 437 438 for (n = kern_db; n; n = n->next) { 439 struct ifstat_ent *h1; 440 for (h1 = h; h1; h1 = h1->next) { 441 if (h1->ifindex == n->ifindex) { 442 int i; 443 for (i = 0; i < MAXS; i++) { 444 if ((long)(h1->ival[i] - n->ival[i]) < 0) { 445 memset(n->ival, 0, sizeof(n->ival)); 446 break; 447 } 448 } 449 for (i = 0; i < MAXS; i++) { 450 double sample; 451 unsigned long incr = h1->ival[i] - n->ival[i]; 452 n->val[i] += incr; 453 n->ival[i] = h1->ival[i]; 454 sample = (double)(incr*1000)/interval; 455 if (interval >= scan_interval) { 456 n->rate[i] += W*(sample-n->rate[i]); 457 } else if (interval >= 1000) { 458 if (interval >= time_constant) { 459 n->rate[i] = sample; 460 } else { 461 double w = W*(double)interval/scan_interval; 462 n->rate[i] += w*(sample-n->rate[i]); 463 } 464 } 465 } 466 467 while (h != h1) { 468 struct ifstat_ent *tmp = h; 469 h = h->next; 470 free(tmp->name); 471 free(tmp); 472 }; 473 h = h1->next; 474 free(h1->name); 475 free(h1); 476 break; 477 } 478 } 479 } 480 } 481 482 #define T_DIFF(a,b) (((a).tv_sec-(b).tv_sec)*1000 + ((a).tv_usec-(b).tv_usec)/1000) 483 484 485 void server_loop(int fd) 486 { 487 struct timeval snaptime = { 0 }; 488 struct pollfd p; 489 p.fd = fd; 490 p.events = p.revents = POLLIN; 491 492 sprintf(info_source, "%d.%lu sampling_interval=%d time_const=%d", 493 getpid(), (unsigned long)random(), scan_interval/1000, time_constant/1000); 494 495 load_info(); 496 497 for (;;) { 498 int status; 499 int tdiff; 500 struct timeval now; 501 502 gettimeofday(&now, NULL); 503 tdiff = T_DIFF(now, snaptime); 504 if (tdiff >= scan_interval) { 505 update_db(tdiff); 506 snaptime = now; 507 tdiff = 0; 508 } 509 510 if (poll(&p, 1, tdiff + scan_interval) > 0 511 && (p.revents&POLLIN)) { 512 int clnt = accept(fd, NULL, NULL); 513 if (clnt >= 0) { 514 pid_t pid; 515 if (children >= 5) { 516 close(clnt); 517 } else if ((pid = fork()) != 0) { 518 if (pid>0) 519 children++; 520 close(clnt); 521 } else { 522 FILE *fp = fdopen(clnt, "w"); 523 if (fp) { 524 if (tdiff > 0) 525 update_db(tdiff); 526 dump_raw_db(fp, 0); 527 } 528 exit(0); 529 } 530 } 531 } 532 while (children && waitpid(-1, &status, WNOHANG) > 0) 533 children--; 534 } 535 } 536 537 int verify_forging(int fd) 538 { 539 struct ucred cred; 540 socklen_t olen = sizeof(cred); 541 542 if (getsockopt(fd, SOL_SOCKET, SO_PEERCRED, (void*)&cred, &olen) || 543 olen < sizeof(cred)) 544 return -1; 545 if (cred.uid == getuid() || cred.uid == 0) 546 return 0; 547 return -1; 548 } 549 550 static void usage(void) __attribute__((noreturn)); 551 552 static void usage(void) 553 { 554 fprintf(stderr, 555 "Usage: ifstat [OPTION] [ PATTERN [ PATTERN ] ]\n" 556 " -h, --help this message\n" 557 " -a, --ignore ignore history\n" 558 " -d, --scan=SECS sample every statistics every SECS\n" 559 " -e, --errors show errors\n" 560 " -n, --nooutput do history only\n" 561 " -r, --reset reset history\n" 562 " -s, --noupdate don;t update history\n" 563 " -t, --interval=SECS report average over the last SECS\n" 564 " -V, --version output version information\n" 565 " -z, --zeros show entries with zero activity\n" 566 " -e, --errors show errors\n" 567 " -z, --zeros show entries with zero activity\n"); 568 569 exit(-1); 570 } 571 572 static const struct option longopts[] = { 573 { "help", 0, 0, 'h' }, 574 { "ignore", 0, 0, 'a' }, 575 { "scan", 1, 0, 'd'}, 576 { "errors", 0, 0, 'e' }, 577 { "nooutput", 0, 0, 'n' }, 578 { "reset", 0, 0, 'r' }, 579 { "noupdate", 0, 0, 's' }, 580 { "interval", 1, 0, 't' }, 581 { "version", 0, 0, 'V' }, 582 { "zeros", 0, 0, 'z' }, 583 { "errors", 0, 0, 'e' }, 584 { "zeros", 0, 0, 'z' }, 585 { 0 } 586 }; 587 588 int main(int argc, char *argv[]) 589 { 590 char hist_name[128]; 591 struct sockaddr_un sun; 592 FILE *hist_fp = NULL; 593 int ch; 594 int fd; 595 596 while ((ch = getopt_long(argc, argv, "hvVzrnasd:t:eK", 597 longopts, NULL)) != EOF) { 598 switch(ch) { 599 case 'z': 600 dump_zeros = 1; 601 break; 602 case 'r': 603 reset_history = 1; 604 break; 605 case 'a': 606 ignore_history = 1; 607 break; 608 case 's': 609 no_update = 1; 610 break; 611 case 'n': 612 no_output = 1; 613 break; 614 case 'e': 615 show_errors = 1; 616 break; 617 case 'd': 618 scan_interval = atoi(optarg) * 1000; 619 if (scan_interval <= 0) { 620 fprintf(stderr, "ifstat: invalid scan interval\n"); 621 exit(-1); 622 } 623 break; 624 case 't': 625 time_constant = atoi(optarg); 626 if (time_constant <= 0) { 627 fprintf(stderr, "ifstat: invalid time constant divisor\n"); 628 exit(-1); 629 } 630 break; 631 case 'v': 632 case 'V': 633 printf("ifstat utility, iproute2-ss%s\n", SNAPSHOT); 634 exit(0); 635 case 'h': 636 case '?': 637 default: 638 usage(); 639 } 640 } 641 642 argc -= optind; 643 argv += optind; 644 645 sun.sun_family = AF_UNIX; 646 sun.sun_path[0] = 0; 647 sprintf(sun.sun_path+1, "ifstat%d", getuid()); 648 649 if (scan_interval > 0) { 650 if (time_constant == 0) 651 time_constant = 60; 652 time_constant *= 1000; 653 W = 1 - 1/exp(log(10)*(double)scan_interval/time_constant); 654 if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) { 655 perror("ifstat: socket"); 656 exit(-1); 657 } 658 if (bind(fd, (struct sockaddr*)&sun, 2+1+strlen(sun.sun_path+1)) < 0) { 659 perror("ifstat: bind"); 660 exit(-1); 661 } 662 if (listen(fd, 5) < 0) { 663 perror("ifstat: listen"); 664 exit(-1); 665 } 666 if (daemon(0, 0)) { 667 perror("ifstat: daemon"); 668 exit(-1); 669 } 670 signal(SIGPIPE, SIG_IGN); 671 signal(SIGCHLD, sigchild); 672 server_loop(fd); 673 exit(0); 674 } 675 676 patterns = argv; 677 npatterns = argc; 678 679 if (getenv("IFSTAT_HISTORY")) 680 snprintf(hist_name, sizeof(hist_name), getenv("IFSTAT_HISTORY")); 681 else 682 sprintf(hist_name, "%s/.ifstat.u%d", P_tmpdir, getuid()); 683 684 if (reset_history) 685 unlink(hist_name); 686 687 if (!ignore_history || !no_update) { 688 struct stat stb; 689 690 fd = open(hist_name, O_RDWR|O_CREAT|O_NOFOLLOW, 0600); 691 if (fd < 0) { 692 perror("ifstat: open history file"); 693 exit(-1); 694 } 695 if ((hist_fp = fdopen(fd, "r+")) == NULL) { 696 perror("ifstat: fdopen history file"); 697 exit(-1); 698 } 699 if (flock(fileno(hist_fp), LOCK_EX)) { 700 perror("ifstat: flock history file"); 701 exit(-1); 702 } 703 if (fstat(fileno(hist_fp), &stb) != 0) { 704 perror("ifstat: fstat history file"); 705 exit(-1); 706 } 707 if (stb.st_nlink != 1 || stb.st_uid != getuid()) { 708 fprintf(stderr, "ifstat: something is so wrong with history file, that I prefer not to proceed.\n"); 709 exit(-1); 710 } 711 if (!ignore_history) { 712 FILE *tfp; 713 long uptime; 714 if ((tfp = fopen("/proc/uptime", "r")) != NULL) { 715 if (fscanf(tfp, "%ld", &uptime) != 1) 716 uptime = -1; 717 fclose(tfp); 718 } 719 if (uptime >= 0 && time(NULL) >= stb.st_mtime+uptime) { 720 fprintf(stderr, "ifstat: history is aged out, resetting\n"); 721 ftruncate(fileno(hist_fp), 0); 722 } 723 } 724 725 load_raw_table(hist_fp); 726 727 hist_db = kern_db; 728 kern_db = NULL; 729 } 730 731 if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) >= 0 && 732 (connect(fd, (struct sockaddr*)&sun, 2+1+strlen(sun.sun_path+1)) == 0 733 || (strcpy(sun.sun_path+1, "ifstat0"), 734 connect(fd, (struct sockaddr*)&sun, 2+1+strlen(sun.sun_path+1)) == 0)) 735 && verify_forging(fd) == 0) { 736 FILE *sfp = fdopen(fd, "r"); 737 load_raw_table(sfp); 738 if (hist_db && source_mismatch) { 739 fprintf(stderr, "ifstat: history is stale, ignoring it.\n"); 740 hist_db = NULL; 741 } 742 fclose(sfp); 743 } else { 744 if (fd >= 0) 745 close(fd); 746 if (hist_db && info_source[0] && strcmp(info_source, "kernel")) { 747 fprintf(stderr, "ifstat: history is stale, ignoring it.\n"); 748 hist_db = NULL; 749 info_source[0] = 0; 750 } 751 load_info(); 752 if (info_source[0] == 0) 753 strcpy(info_source, "kernel"); 754 } 755 756 if (!no_output) { 757 if (ignore_history || hist_db == NULL) 758 dump_kern_db(stdout); 759 else 760 dump_incr_db(stdout); 761 } 762 if (!no_update) { 763 ftruncate(fileno(hist_fp), 0); 764 rewind(hist_fp); 765 dump_raw_db(hist_fp, 1); 766 fflush(hist_fp); 767 } 768 exit(0); 769 } 770
