tap-iostat.c

   1 /* tap-iostat.c
   2  * iostat   2002 Ronnie Sahlberg
   3  *
   4  * $Id$
   5  *
   6  * Wireshark - Network traffic analyzer
   7  * By Gerald Combs <gerald@wireshark.org>
   8  * Copyright 1998 Gerald Combs
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public License
  12  * as published by the Free Software Foundation; either version 2
  13  * of the License, or (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  23  */
  24
  25 #ifdef HAVE_CONFIG_H
  26 # include "config.h"
  27 #endif
  28
  29 #include <stdio.h>
  30
  31 #ifdef HAVE_SYS_TYPES_H
  32 # include <sys/types.h>
  33 #endif
  34
  35 #include <string.h>
  36 #include "epan/epan_dissect.h"
  37 #include "epan/packet_info.h"
  38 #include <epan/tap.h>
  39 #include <epan/stat_cmd_args.h>
  40 #include <epan/strutil.h>
  41 #include "register.h"
  42
  43
  44 typedef struct _io_stat_t {
  45         gint32 interval;        /* unit is ms */
  46         guint32 num_items;
  47         struct _io_stat_item_t *items;
  48         const char **filters;
  49 } io_stat_t;
  50
  51 #define CALC_TYPE_BYTES 0
  52 #define CALC_TYPE_COUNT 1
  53 #define CALC_TYPE_SUM   2
  54 #define CALC_TYPE_MIN   3
  55 #define CALC_TYPE_MAX   4
  56 #define CALC_TYPE_AVG   5
  57
  58 typedef struct _io_stat_item_t {
  59         io_stat_t *parent;
  60         struct _io_stat_item_t *next;
  61         struct _io_stat_item_t *prev;
  62         gint32 time;            /* unit is ms since start of capture */
  63         int calc_type;
  64         int hf_index;
  65         guint32 frames;
  66         guint32 num;
  67         guint32 counter;
  68 } io_stat_item_t;
  69
  70
  71 static int
  72 iostat_packet(void *arg, packet_info *pinfo, epan_dissect_t *edt _U_, const void *dummy _U_)
  73 {
  74         io_stat_item_t *mit = arg;
  75         io_stat_item_t *it;
  76         gint32 current_time;
  77         GPtrArray *gp;
  78         guint i;
  79
  80         current_time=(gint32) ((pinfo->fd->rel_ts.secs*1000)+(pinfo->fd->rel_ts.nsecs/1000000));
  81
  82         /* the prev item before the main one is always the last interval we saw packets for */
  83         it=mit->prev;
  84
  85         /* XXX for the time being, just ignore all frames that are in the past.
  86            should be fixed in the future but hopefully it is uncommon */
  87         if(current_time<it->time){
  88                 return FALSE;
  89         }
  90
  91         /* we have moved into a new interval, we need to create a new struct */
  92         if(current_time>=(it->time+mit->parent->interval)){
  93                 it->next=g_malloc(sizeof(io_stat_item_t));
  94                 it->next->prev=it;
  95                 it->next->next=NULL;
  96                 it=it->next;
  97                 mit->prev=it;
  98
  99                 it->time=(current_time / mit->parent->interval) * mit->parent->interval;
 100                 it->frames=0;
 101                 it->counter=0;
 102                 it->num=0;
 103                 it->calc_type=it->prev->calc_type;
 104                 it->hf_index=it->prev->hf_index;
 105         }
 106
 107         /* it will now give us the current structure to use to store the data in */
 108         it->frames++;
 109
 110         switch(it->calc_type){
 111         case CALC_TYPE_BYTES:
 112                 it->counter+=pinfo->fd->pkt_len;
 113                 break;
 114         case CALC_TYPE_COUNT:
 115                 gp=proto_get_finfo_ptr_array(edt->tree, it->hf_index);
 116                 if(gp){
 117                         it->counter+=gp->len;
 118                 }
 119                 break;
 120         case CALC_TYPE_SUM:
 121                 gp=proto_get_finfo_ptr_array(edt->tree, it->hf_index);
 122                 if(gp){
 123                         for(i=0;i<gp->len;i++){
 124                                 switch(proto_registrar_get_ftype(it->hf_index)){
 125                                 case FT_UINT8:
 126                                 case FT_UINT16:
 127                                 case FT_UINT24:
 128                                 case FT_UINT32:
 129                                         it->counter+=fvalue_get_uinteger(&((field_info *)gp->pdata[i])->value);
 130                                         break;
 131                                 case FT_INT8:
 132                                 case FT_INT16:
 133                                 case FT_INT24:
 134                                 case FT_INT32:
 135                                         it->counter+=fvalue_get_sinteger(&((field_info *)gp->pdata[i])->value);
 136                                         break;
 137                                 }
 138                         }
 139                 }
 140                 break;
 141         case CALC_TYPE_MIN:
 142                 gp=proto_get_finfo_ptr_array(edt->tree, it->hf_index);
 143                 if(gp){
 144                         int type;
 145                         guint32 val;
 146                         nstime_t *new_time;
 147
 148                         type=proto_registrar_get_ftype(it->hf_index);
 149                         for(i=0;i<gp->len;i++){
 150                                 switch(type){
 151                                 case FT_UINT8:
 152                                 case FT_UINT16:
 153                                 case FT_UINT24:
 154                                 case FT_UINT32:
 155                                         val=fvalue_get_uinteger(&((field_info *)gp->pdata[i])->value);
 156                                         if((it->frames==1)&&(i==0)){
 157                                                 it->counter=val;
 158                                         } else if(val<it->counter){
 159                                                 it->counter=val;
 160                                         }
 161                                         break;
 162                                 case FT_INT8:
 163                                 case FT_INT16:
 164                                 case FT_INT24:
 165                                 case FT_INT32:
 166                                         val=fvalue_get_sinteger(&((field_info *)gp->pdata[i])->value);
 167                                         if((it->frames==1)&&(i==0)){
 168                                                 it->counter=val;
 169                                         } else if((gint32)val<(gint32)(it->counter)){
 170                                                 it->counter=val;
 171                                         }
 172                                         break;
 173                                 case FT_RELATIVE_TIME:
 174                                         new_time=fvalue_get(&((field_info *)gp->pdata[i])->value);
 175                                         val=(guint32) (new_time->secs*1000+new_time->nsecs/1000000);
 176                                         if((it->frames==1)&&(i==0)){
 177                                                 it->counter=val;
 178                                         } else if(val<it->counter){
 179                                                 it->counter=val;
 180                                         }
 181                                         break;
 182                                 }
 183                         }
 184                 }
 185                 break;
 186         case CALC_TYPE_MAX:
 187                 gp=proto_get_finfo_ptr_array(edt->tree, it->hf_index);
 188                 if(gp){
 189                         int type;
 190                         guint32 val;
 191                         nstime_t *new_time;
 192
 193                         type=proto_registrar_get_ftype(it->hf_index);
 194                         for(i=0;i<gp->len;i++){
 195                                 switch(type){
 196                                 case FT_UINT8:
 197                                 case FT_UINT16:
 198                                 case FT_UINT24:
 199                                 case FT_UINT32:
 200                                         val=fvalue_get_uinteger(&((field_info *)gp->pdata[i])->value);
 201                                         if((it->frames==1)&&(i==0)){
 202                                                 it->counter=val;
 203                                         } else if(val>it->counter){
 204                                                 it->counter=val;
 205                                         }
 206                                         break;
 207                                 case FT_INT8:
 208                                 case FT_INT16:
 209                                 case FT_INT24:
 210                                 case FT_INT32:
 211                                         val=fvalue_get_sinteger(&((field_info *)gp->pdata[i])->value);
 212                                         if((it->frames==1)&&(i==0)){
 213                                                 it->counter=val;
 214                                         } else if((gint32)val>(gint32)(it->counter)){
 215                                                 it->counter=val;
 216                                         }
 217                                         break;
 218                                 case FT_RELATIVE_TIME:
 219                                         new_time=fvalue_get(&((field_info *)gp->pdata[i])->value);
 220                                         val=(guint32) (new_time->secs*1000+new_time->nsecs/1000000);
 221                                         if((it->frames==1)&&(i==0)){
 222                                                 it->counter=val;
 223                                         } else if(val>it->counter){
 224                                                 it->counter=val;
 225                                         }
 226                                         break;
 227                                 }
 228                         }
 229                 }
 230                 break;
 231         case CALC_TYPE_AVG:
 232                 gp=proto_get_finfo_ptr_array(edt->tree, it->hf_index);
 233                 if(gp){
 234                         int type;
 235                         guint32 val;
 236                         nstime_t *new_time;
 237
 238                         type=proto_registrar_get_ftype(it->hf_index);
 239                         for(i=0;i<gp->len;i++){
 240                                 it->num++;
 241                                 switch(type){
 242                                 case FT_UINT8:
 243                                 case FT_UINT16:
 244                                 case FT_UINT24:
 245                                 case FT_UINT32:
 246                                         val=fvalue_get_uinteger(&((field_info *)gp->pdata[i])->value);
 247                                         it->counter+=val;
 248                                         break;
 249                                 case FT_INT8:
 250                                 case FT_INT16:
 251                                 case FT_INT24:
 252                                 case FT_INT32:
 253                                         val=fvalue_get_sinteger(&((field_info *)gp->pdata[i])->value);
 254                                         it->counter+=val;
 255                                         break;
 256                                 case FT_RELATIVE_TIME:
 257                                         new_time=fvalue_get(&((field_info *)gp->pdata[i])->value);
 258                                         val=(guint32) (new_time->secs*1000+new_time->nsecs/1000000);
 259                                         it->counter+=val;
 260                                         break;
 261                                 }
 262                         }
 263                 }
 264                 break;
 265         }
 266
 267         return TRUE;
 268 }
 269
 270 static void
 271 iostat_draw(void *arg)
 272 {
 273         io_stat_item_t *mit = arg;
 274         io_stat_t *iot;
 275         io_stat_item_t **items;
 276         guint32 *frames;
 277         guint32 *counters;
 278         guint32 *num;
 279         guint32 i,more_items;
 280         gint t;
 281
 282         iot=mit->parent;
 283
 284         printf("\n");
 285         printf("===================================================================\n");
 286         printf("IO Statistics\n");
 287         printf("Interval: %d.%03d secs\n", iot->interval/1000, iot->interval%1000);
 288         for(i=0;i<iot->num_items;i++){
 289                 printf("Column #%d: %s\n",i,iot->filters[i]?iot->filters[i]:"");
 290         }
 291         printf("                ");
 292         for(i=0;i<iot->num_items;i++){
 293                 printf("|   Column #%-2d   ",i);
 294         }
 295         printf("\n");
 296         printf("Time            ");
 297         for(i=0;i<iot->num_items;i++){
 298                 switch(iot->items[i].calc_type){
 299                 case CALC_TYPE_BYTES:
 300                         printf("|frames|  bytes  ");
 301                         break;
 302                 case CALC_TYPE_COUNT:
 303                         printf("|          COUNT ");
 304                         break;
 305                 case CALC_TYPE_SUM:
 306                         printf("|            SUM ");
 307                         break;
 308                 case CALC_TYPE_MIN:
 309                         printf("|            MIN ");
 310                         break;
 311                 case CALC_TYPE_MAX:
 312                         printf("|            MAX ");
 313                         break;
 314                 case CALC_TYPE_AVG:
 315                         printf("|            AVG ");
 316                         break;
 317                 }
 318         }
 319         printf("\n");
 320
 321         items=g_malloc(sizeof(io_stat_item_t *)*iot->num_items);
 322         frames=g_malloc(sizeof(guint32)*iot->num_items);
 323         counters=g_malloc(sizeof(guint32)*iot->num_items);
 324         num=g_malloc(sizeof(guint32)*iot->num_items);
 325         /* preset all items at the first interval */
 326         for(i=0;i<iot->num_items;i++){
 327                 items[i]=&iot->items[i];
 328         }
 329
 330         /* loop the items until we run out of them all */
 331         t=0;
 332         do {
 333                 more_items=0;
 334                 for(i=0;i<iot->num_items;i++){
 335                         frames[i]=0;
 336                         counters[i]=0;
 337                         num[i]=0;
 338                 }
 339                 for(i=0;i<iot->num_items;i++){
 340                         if(items[i] && (t>=(items[i]->time+iot->interval))){
 341                                 items[i]=items[i]->next;
 342                         }
 343
 344                         if(items[i] && (t<(items[i]->time+iot->interval)) && (t>=items[i]->time) ){
 345                                 frames[i]=items[i]->frames;
 346                                 counters[i]=items[i]->counter;
 347                                 num[i]=items[i]->num;
 348                         }
 349
 350                         if(items[i]){
 351                                 more_items=1;
 352                         }
 353                 }
 354
 355                 if(more_items){
 356                         printf("%03d.%03d-%03d.%03d  ",
 357                                 t/1000,t%1000,
 358                                 (t+iot->interval)/1000,(t+iot->interval)%1000);
 359                         for(i=0;i<iot->num_items;i++){
 360                                 switch(iot->items[i].calc_type){
 361                                 case CALC_TYPE_BYTES:
 362                                         printf("%6d %9d ",frames[i],counters[i]);
 363                                         break;
 364                                 case CALC_TYPE_COUNT:
 365                                         printf("        %8d ", counters[i]);
 366                                         break;
 367                                 case CALC_TYPE_SUM:
 368                                         printf("        %8d ", counters[i]);
 369                                         break;
 370                                 case CALC_TYPE_MIN:
 371                                         switch(proto_registrar_get_ftype(iot->items[i].hf_index)){
 372                                         case FT_UINT8:
 373                                         case FT_UINT16:
 374                                         case FT_UINT24:
 375                                         case FT_UINT32:
 376                                                 printf("        %8u ", counters[i]);
 377                                                 break;
 378                                         case FT_INT8:
 379                                         case FT_INT16:
 380                                         case FT_INT24:
 381                                         case FT_INT32:
 382                                                 printf("        %8d ", counters[i]);
 383                                                 break;
 384                                         case FT_RELATIVE_TIME:
 385                                                 printf("      %6d.%03d ", counters[i]/1000, counters[i]%1000);
 386                                                 break;
 387                                         }
 388                                         break;
 389                                 case CALC_TYPE_MAX:
 390                                         switch(proto_registrar_get_ftype(iot->items[i].hf_index)){
 391                                         case FT_UINT8:
 392                                         case FT_UINT16:
 393                                         case FT_UINT24:
 394                                         case FT_UINT32:
 395                                                 printf("        %8u ", counters[i]);
 396                                                 break;
 397                                         case FT_INT8:
 398                                         case FT_INT16:
 399                                         case FT_INT24:
 400                                         case FT_INT32:
 401                                                 printf("        %8d ", counters[i]);
 402                                                 break;
 403                                         case FT_RELATIVE_TIME:
 404                                                 printf("      %6d.%03d ", counters[i]/1000, counters[i]%1000);
 405                                                 break;
 406                                         }
 407                                         break;
 408                                 case CALC_TYPE_AVG:
 409                                         if(num[i]==0){
 410                                                 num[i]=1;
 411                                         }
 412                                         switch(proto_registrar_get_ftype(iot->items[i].hf_index)){
 413                                         case FT_UINT8:
 414                                         case FT_UINT16:
 415                                         case FT_UINT24:
 416                                         case FT_UINT32:
 417                                                 printf("        %8u ", counters[i]/num[i]);
 418                                                 break;
 419                                         case FT_INT8:
 420                                         case FT_INT16:
 421                                         case FT_INT24:
 422                                         case FT_INT32:
 423                                                 printf("        %8d ", counters[i]/num[i]);
 424                                                 break;
 425                                         case FT_RELATIVE_TIME:
 426                                                 counters[i]/=num[i];
 427                                                 printf("      %6d.%03d ", counters[i]/1000, counters[i]%1000);
 428                                                 break;
 429                                         }
 430                                         break;
 431
 432                                 }
 433                         }
 434                         printf("\n");
 435                 }
 436
 437                 t+=iot->interval;
 438         } while(more_items);
 439
 440         printf("===================================================================\n");
 441
 442         g_free(items);
 443         g_free(frames);
 444         g_free(counters);
 445         g_free(num);
 446 }
 447
 448
 449 typedef struct {
 450         const char *func_name;
 451         int calc_type;
 452 } calc_type_ent_t;
 453
 454 static calc_type_ent_t calc_type_table[] = {
 455         { "COUNT", CALC_TYPE_COUNT },
 456         { "SUM", CALC_TYPE_SUM },
 457         { "MIN", CALC_TYPE_MIN },
 458         { "MAX", CALC_TYPE_MAX },
 459         { "AVG", CALC_TYPE_AVG },
 460         { NULL, 0 }
 461 };
 462
 463 static void
 464 register_io_tap(io_stat_t *io, int i, const char *filter)
 465 {
 466         GString *error_string;
 467         const char *flt;
 468         int j;
 469         size_t namelen;
 470         const char *p, *parenp;
 471         char *field;
 472         header_field_info *hfi;
 473
 474         io->items[i].prev=&io->items[i];
 475         io->items[i].next=NULL;
 476         io->items[i].parent=io;
 477         io->items[i].time=0;
 478         io->items[i].calc_type=CALC_TYPE_BYTES;
 479         io->items[i].frames=0;
 480         io->items[i].counter=0;
 481         io->items[i].num=0;
 482         io->filters[i]=filter;
 483         flt=filter;
 484
 485         if(!filter){
 486                 filter="";
 487         }
 488         field=NULL;
 489         hfi=NULL;
 490         for(j=0; calc_type_table[j].func_name; j++){
 491                 namelen=strlen(calc_type_table[j].func_name);
 492                 if(strncmp(filter, calc_type_table[j].func_name, namelen) == 0
 493                     && *(filter+namelen)=='('){
 494                         io->items[i].calc_type=calc_type_table[j].calc_type;
 495
 496                         p=filter+namelen+1;
 497                         parenp=strchr(p, ')');
 498                         if(!parenp){
 499                                 fprintf(stderr, "tshark: Closing parenthesis missing from calculated expression.\n");
 500                                 exit(10);
 501                         }
 502                         /* bail out if there was no field specified */
 503                         if(parenp==p){
 504                                 fprintf(stderr, "tshark: You didn't specify a field name for %s(*).\n",
 505                                     calc_type_table[j].func_name);
 506                                 exit(10);
 507                         }
 508                         field=g_malloc(parenp-p+1);
 509                         if(!field){
 510                                 fprintf(stderr, "tshark: Out of memory.\n");
 511                                 exit(10);
 512                         }
 513                         memcpy(field, p, parenp-p);
 514                         field[parenp-p] = '\0';
 515                         flt=parenp + 1;
 516
 517                         hfi=proto_registrar_get_byname(field);
 518                         if(!hfi){
 519                                 fprintf(stderr, "tshark: There is no field named '%s'.\n",
 520                                     field);
 521                                 g_free(field);
 522                                 exit(10);
 523                         }
 524
 525                         io->items[i].hf_index=hfi->id;
 526                         break;
 527                 }
 528         }
 529         if(io->items[i].calc_type!=CALC_TYPE_BYTES){
 530                 /* check that the type is compatible */
 531                 switch(hfi->type){
 532                 case FT_UINT8:
 533                 case FT_UINT16:
 534                 case FT_UINT24:
 535                 case FT_UINT32:
 536                 case FT_INT8:
 537                 case FT_INT16:
 538                 case FT_INT24:
 539                 case FT_INT32:
 540                         /* these types support all calculations */
 541                         break;
 542                 case FT_RELATIVE_TIME:
 543                         /* this type only supports SUM, COUNT, MAX, MIN, AVG */
 544                         switch(io->items[i].calc_type){
 545                         case CALC_TYPE_SUM:
 546                         case CALC_TYPE_COUNT:
 547                         case CALC_TYPE_MAX:
 548                         case CALC_TYPE_MIN:
 549                         case CALC_TYPE_AVG:
 550                                 break;
 551                         default:
 552                                 fprintf(stderr,
 553                                     "tshark: %s is a relative-time field, so %s(*) calculations are not supported on it.",
 554                                     field,
 555                                     calc_type_table[j].func_name);
 556                                 exit(10);
 557                         }
 558                         break;
 559                 case FT_UINT64:
 560                 case FT_INT64:
 561                         /*
 562                          * XXX - support this if gint64/guint64 are
 563                          * available?
 564                          */
 565                         if(io->items[i].calc_type!=CALC_TYPE_COUNT){
 566                                 fprintf(stderr,
 567                                     "tshark: %s is a 64-bit integer, so %s(*) calculations are not supported on it.",
 568                                     field,
 569                                     calc_type_table[j].func_name);
 570                                 exit(10);
 571                         }
 572                         break;
 573                 default:
 574                         /*
 575                          * XXX - support all operations on floating-point
 576                          * numbers?
 577                          */
 578                         if(io->items[i].calc_type!=CALC_TYPE_COUNT){
 579                                 fprintf(stderr,
 580                                     "tshark: %s doesn't have integral values, so %s(*) calculations are not supported on it.\n",
 581                                     field,
 582                                     calc_type_table[j].func_name);
 583                                 exit(10);
 584                         }
 585                         break;
 586                 }
 587                 g_free(field);
 588         }
 589
 590 /*
 591 CALC_TYPE_SUM   2
 592 CALC_TYPE_MIN   3
 593 CALC_TYPE_MAX   4
 594 CALC_TYPE_AVG   5
 595 */
 596
 597         error_string=register_tap_listener("frame", &io->items[i], flt, NULL, iostat_packet, i?NULL:iostat_draw);
 598         if(error_string){
 599                 g_free(io->items);
 600                 g_free(io);
 601                 fprintf(stderr, "tshark: Couldn't register io,stat tap: %s\n",
 602                     error_string->str);
 603                 g_string_free(error_string, TRUE);
 604                 exit(1);
 605         }
 606 }
 607
 608 void
 609 iostat_init(const char *optarg, void* userdata _U_)
 610 {
 611         float interval_float;
 612         gint32 interval;
 613         int pos=0;
 614         io_stat_t *io;
 615         const char *filter=NULL;
 616
 617         if(sscanf(optarg,"io,stat,%f,%n",&interval_float,&pos)==1){
 618                 if(pos){
 619                         filter=optarg+pos;
 620                 } else {
 621                         filter=NULL;
 622                 }
 623         } else {
 624                 fprintf(stderr, "tshark: invalid \"-z io,stat,<interval>[,<filter>]\" argument\n");
 625                 exit(1);
 626         }
 627
 628
 629         /* make interval be number of ms */
 630         interval=(gint32)(interval_float*1000.0+0.9);
 631         if(interval<1){
 632                 fprintf(stderr, "tshark: \"-z\" interval must be >=0.001 seconds.\n");
 633                 exit(10);
 634         }
 635
 636         io=g_malloc(sizeof(io_stat_t));
 637         io->interval=interval;
 638         if((!filter)||(filter[0]==0)){
 639                 io->num_items=1;
 640                 io->items=g_malloc(sizeof(io_stat_item_t)*io->num_items);
 641                 io->filters=g_malloc(sizeof(char *)*io->num_items);
 642
 643                 register_io_tap(io, 0, NULL);
 644         } else {
 645                 const char *str,*pos;
 646                 char *tmp;
 647                 int i;
 648                 /* find how many ',' separated filters we have */
 649                 str=filter;
 650                 io->num_items=1;
 651                 while((str=strchr(str,','))){
 652                         io->num_items++;
 653                         str++;
 654                 }
 655
 656                 io->items=g_malloc(sizeof(io_stat_item_t)*io->num_items);
 657                 io->filters=g_malloc(sizeof(char *)*io->num_items);
 658
 659                 /* for each filter, register a tap listener */
 660                 i=0;
 661                 str=filter;
 662                 do{
 663                         pos=strchr(str,',');
 664                         if(pos==str){
 665                                 register_io_tap(io, i, NULL);
 666                         } else if(pos==NULL) {
 667                                 tmp=g_strdup(str);
 668                                 register_io_tap(io, i, tmp);
 669                         } else {
 670                                 tmp=g_malloc((pos-str)+1);
 671                                 g_strlcpy(tmp,str,(pos-str)+1);
 672                                 register_io_tap(io, i, tmp);
 673                         }
 674                         str=pos+1;
 675                         i++;
 676                 } while(pos);
 677         }
 678 }
 679
 680 void
 681 register_tap_listener_iostat(void)
 682 {
 683         register_stat_cmd_arg("io,stat,", iostat_init, NULL);
 684 }