src/bin/lttng/commands/list.c

   1 /*
   2  * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License, version 2 only,
   6  * as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  16  */
  17
  18 #define _GNU_SOURCE
  19 #include <inttypes.h>
  20 #include <popt.h>
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <string.h>
  24 #include <assert.h>
  25
  26 #include "../command.h"
  27
  28 static int opt_userspace;
  29 static int opt_kernel;
  30 static char *opt_channel;
  31 static int opt_domain;
  32 static int opt_fields;
  33 #if 0
  34 /* Not implemented yet */
  35 static char *opt_cmd_name;
  36 static pid_t opt_pid;
  37 #endif
  38
  39 const char *indent4 = "    ";
  40 const char *indent6 = "      ";
  41 const char *indent8 = "        ";
  42
  43 enum {
  44         OPT_HELP = 1,
  45         OPT_USERSPACE,
  46         OPT_LIST_OPTIONS,
  47 };
  48
  49 static struct lttng_handle *handle;
  50
  51 static struct poptOption long_options[] = {
  52         /* longName, shortName, argInfo, argPtr, value, descrip, argDesc */
  53         {"help",      'h', POPT_ARG_NONE, 0, OPT_HELP, 0, 0},
  54         {"kernel",    'k', POPT_ARG_VAL, &opt_kernel, 1, 0, 0},
  55 #if 0
  56         /* Not implemented yet */
  57         {"userspace",      'u', POPT_ARG_STRING | POPT_ARGFLAG_OPTIONAL, &opt_cmd_name, OPT_USERSPACE, 0, 0},
  58         {"pid",            'p', POPT_ARG_INT, &opt_pid, 0, 0, 0},
  59 #else
  60         {"userspace",      'u', POPT_ARG_NONE, 0, OPT_USERSPACE, 0, 0},
  61 #endif
  62         {"channel",   'c', POPT_ARG_STRING, &opt_channel, 0, 0, 0},
  63         {"domain",    'd', POPT_ARG_VAL, &opt_domain, 1, 0, 0},
  64         {"fields",    'f', POPT_ARG_VAL, &opt_fields, 1, 0, 0},
  65         {"list-options", 0, POPT_ARG_NONE, NULL, OPT_LIST_OPTIONS, NULL, NULL},
  66         {0, 0, 0, 0, 0, 0, 0}
  67 };
  68
  69 /*
  70  * usage
  71  */
  72 static void usage(FILE *ofp)
  73 {
  74         fprintf(ofp, "usage: lttng list [OPTIONS] [SESSION [<OPTIONS>]]\n");
  75         fprintf(ofp, "\n");
  76         fprintf(ofp, "With no arguments, list available tracing session(s)\n");
  77         fprintf(ofp, "\n");
  78         fprintf(ofp, "Without a session, -k lists available kernel events\n");
  79         fprintf(ofp, "Without a session, -u lists available userspace events\n");
  80         fprintf(ofp, "\n");
  81         fprintf(ofp, "  -h, --help              Show this help\n");
  82         fprintf(ofp, "      --list-options      Simple listing of options\n");
  83         fprintf(ofp, "  -k, --kernel            Select kernel domain\n");
  84         fprintf(ofp, "  -u, --userspace         Select user-space domain.\n");
  85         fprintf(ofp, "  -f, --fields            List event fields.\n");
  86 #if 0
  87         fprintf(ofp, "  -p, --pid PID           List user-space events by PID\n");
  88 #endif
  89         fprintf(ofp, "\n");
  90         fprintf(ofp, "Session Options:\n");
  91         fprintf(ofp, "  -c, --channel NAME      List details of a channel\n");
  92         fprintf(ofp, "  -d, --domain            List available domain(s)\n");
  93         fprintf(ofp, "\n");
  94 }
  95
  96 /*
  97  * Get command line from /proc for a specific pid.
  98  *
  99  * On success, return an allocated string pointer to the proc cmdline.
 100  * On error, return NULL.
 101  */
 102 static char *get_cmdline_by_pid(pid_t pid)
 103 {
 104         int ret;
 105         FILE *fp;
 106         char *cmdline = NULL;
 107         char path[24];  /* Can't go bigger than /proc/65535/cmdline */
 108
 109         snprintf(path, sizeof(path), "/proc/%d/cmdline", pid);
 110         fp = fopen(path, "r");
 111         if (fp == NULL) {
 112                 goto end;
 113         }
 114
 115         /* Caller must free() *cmdline */
 116         cmdline = malloc(PATH_MAX);
 117         ret = fread(cmdline, 1, PATH_MAX, fp);
 118         if (ret < 0) {
 119                 perror("fread proc list");
 120         }
 121         fclose(fp);
 122
 123 end:
 124         return cmdline;
 125 }
 126
 127 static
 128 const char *active_string(int value)
 129 {
 130         switch (value) {
 131         case 0: return " [inactive]";
 132         case 1: return " [active]";
 133         case -1: return "";
 134         default: return NULL;
 135         }
 136 }
 137
 138 static
 139 const char *enabled_string(int value)
 140 {
 141         switch (value) {
 142         case 0: return " [disabled]";
 143         case 1: return " [enabled]";
 144         case -1: return "";
 145         default: return NULL;
 146         }
 147 }
 148
 149 static
 150 const char *filter_string(int value)
 151 {
 152         switch (value) {
 153         case 1: return " [with filter]";
 154         default: return "";
 155         }
 156 }
 157
 158 static const char *loglevel_string(int value)
 159 {
 160         switch (value) {
 161         case -1:
 162                 return "";
 163         case LTTNG_LOGLEVEL_EMERG:
 164                 return "TRACE_EMERG";
 165         case LTTNG_LOGLEVEL_ALERT:
 166                 return "TRACE_ALERT";
 167         case LTTNG_LOGLEVEL_CRIT:
 168                 return "TRACE_CRIT";
 169         case LTTNG_LOGLEVEL_ERR:
 170                 return "TRACE_ERR";
 171         case LTTNG_LOGLEVEL_WARNING:
 172                 return "TRACE_WARNING";
 173         case LTTNG_LOGLEVEL_NOTICE:
 174                 return "TRACE_NOTICE";
 175         case LTTNG_LOGLEVEL_INFO:
 176                 return "TRACE_INFO";
 177         case LTTNG_LOGLEVEL_DEBUG_SYSTEM:
 178                 return "TRACE_DEBUG_SYSTEM";
 179         case LTTNG_LOGLEVEL_DEBUG_PROGRAM:
 180                 return "TRACE_DEBUG_PROGRAM";
 181         case LTTNG_LOGLEVEL_DEBUG_PROCESS:
 182                 return "TRACE_DEBUG_PROCESS";
 183         case LTTNG_LOGLEVEL_DEBUG_MODULE:
 184                 return "TRACE_DEBUG_MODULE";
 185         case LTTNG_LOGLEVEL_DEBUG_UNIT:
 186                 return "TRACE_DEBUG_UNIT";
 187         case LTTNG_LOGLEVEL_DEBUG_FUNCTION:
 188                 return "TRACE_DEBUG_FUNCTION";
 189         case LTTNG_LOGLEVEL_DEBUG_LINE:
 190                 return "TRACE_DEBUG_LINE";
 191         case LTTNG_LOGLEVEL_DEBUG:
 192                 return "TRACE_DEBUG";
 193         default:
 194                 return "<<UNKNOWN>>";
 195         }
 196 }
 197
 198 /*
 199  * Pretty print single event.
 200  */
 201 static void print_events(struct lttng_event *event)
 202 {
 203         switch (event->type) {
 204         case LTTNG_EVENT_TRACEPOINT:
 205         {
 206                 if (event->loglevel != -1) {
 207                         MSG("%s%s (loglevel: %s (%d)) (type: tracepoint)%s%s",
 208                                 indent6,
 209                                 event->name,
 210                                 loglevel_string(event->loglevel),
 211                                 event->loglevel,
 212                                 enabled_string(event->enabled),
 213                                 filter_string(event->filter));
 214                 } else {
 215                         MSG("%s%s (type: tracepoint)%s%s",
 216                                 indent6,
 217                                 event->name,
 218                                 enabled_string(event->enabled),
 219                                 filter_string(event->filter));
 220                 }
 221                 break;
 222         }
 223         case LTTNG_EVENT_PROBE:
 224                 MSG("%s%s (type: probe)%s%s", indent6,
 225                                 event->name, enabled_string(event->enabled),
 226                                 filter_string(event->filter));
 227                 if (event->attr.probe.addr != 0) {
 228                         MSG("%saddr: 0x%" PRIx64, indent8, event->attr.probe.addr);
 229                 } else {
 230                         MSG("%soffset: 0x%" PRIx64, indent8, event->attr.probe.offset);
 231                         MSG("%ssymbol: %s", indent8, event->attr.probe.symbol_name);
 232                 }
 233                 break;
 234         case LTTNG_EVENT_FUNCTION:
 235         case LTTNG_EVENT_FUNCTION_ENTRY:
 236                 MSG("%s%s (type: function)%s%s", indent6,
 237                                 event->name, enabled_string(event->enabled),
 238                                 filter_string(event->filter));
 239                 MSG("%ssymbol: \"%s\"", indent8, event->attr.ftrace.symbol_name);
 240                 break;
 241         case LTTNG_EVENT_SYSCALL:
 242                 MSG("%ssyscalls (type: syscall)%s%s", indent6,
 243                                 enabled_string(event->enabled),
 244                                 filter_string(event->filter));
 245                 break;
 246         case LTTNG_EVENT_NOOP:
 247                 MSG("%s (type: noop)%s%s", indent6,
 248                                 enabled_string(event->enabled),
 249                                 filter_string(event->filter));
 250                 break;
 251         case LTTNG_EVENT_ALL:
 252                 /* We should never have "all" events in list. */
 253                 assert(0);
 254                 break;
 255         }
 256 }
 257
 258 static const char *field_type(struct lttng_event_field *field)
 259 {
 260         switch(field->type) {
 261         case LTTNG_EVENT_FIELD_INTEGER:
 262                 return "integer";
 263         case LTTNG_EVENT_FIELD_ENUM:
 264                 return "enum";
 265         case LTTNG_EVENT_FIELD_FLOAT:
 266                 return "float";
 267         case LTTNG_EVENT_FIELD_STRING:
 268                 return "string";
 269         case LTTNG_EVENT_FIELD_OTHER:
 270         default:        /* fall-through */
 271                 return "unknown";
 272         }
 273 }
 274
 275 /*
 276  * Pretty print single event fields.
 277  */
 278 static void print_event_field(struct lttng_event_field *field)
 279 {
 280         if (!field->field_name[0]) {
 281                 return;
 282         }
 283         MSG("%sfield: %s (%s)%s", indent8, field->field_name,
 284                 field_type(field), field->nowrite ? " [no write]" : "");
 285 }
 286
 287 /*
 288  * Ask session daemon for all user space tracepoints available.
 289  */
 290 static int list_ust_events(void)
 291 {
 292         int i, size;
 293         struct lttng_domain domain;
 294         struct lttng_handle *handle;
 295         struct lttng_event *event_list;
 296         pid_t cur_pid = 0;
 297         char *cmdline = NULL;
 298
 299         memset(&domain, 0, sizeof(domain));
 300
 301         DBG("Getting UST tracing events");
 302
 303         domain.type = LTTNG_DOMAIN_UST;
 304
 305         handle = lttng_create_handle(NULL, &domain);
 306         if (handle == NULL) {
 307                 goto error;
 308         }
 309
 310         size = lttng_list_tracepoints(handle, &event_list);
 311         if (size < 0) {
 312                 ERR("Unable to list UST events");
 313                 lttng_destroy_handle(handle);
 314                 return size;
 315         }
 316
 317         MSG("UST events:\n-------------");
 318
 319         if (size == 0) {
 320                 MSG("None");
 321         }
 322
 323         for (i = 0; i < size; i++) {
 324                 if (cur_pid != event_list[i].pid) {
 325                         cur_pid = event_list[i].pid;
 326                         cmdline = get_cmdline_by_pid(cur_pid);
 327                         MSG("\nPID: %d - Name: %s", cur_pid, cmdline);
 328                         free(cmdline);
 329                 }
 330                 print_events(&event_list[i]);
 331         }
 332
 333         MSG("");
 334
 335         free(event_list);
 336         lttng_destroy_handle(handle);
 337
 338         return CMD_SUCCESS;
 339
 340 error:
 341         lttng_destroy_handle(handle);
 342         return -1;
 343 }
 344
 345 /*
 346  * Ask session daemon for all user space tracepoint fields available.
 347  */
 348 static int list_ust_event_fields(void)
 349 {
 350         int i, size;
 351         struct lttng_domain domain;
 352         struct lttng_handle *handle;
 353         struct lttng_event_field *event_field_list;
 354         pid_t cur_pid = 0;
 355         char *cmdline = NULL;
 356
 357         struct lttng_event cur_event;
 358
 359         memset(&domain, 0, sizeof(domain));
 360         memset(&cur_event, 0, sizeof(cur_event));
 361
 362         DBG("Getting UST tracing event fields");
 363
 364         domain.type = LTTNG_DOMAIN_UST;
 365
 366         handle = lttng_create_handle(NULL, &domain);
 367         if (handle == NULL) {
 368                 goto error;
 369         }
 370
 371         size = lttng_list_tracepoint_fields(handle, &event_field_list);
 372         if (size < 0) {
 373                 ERR("Unable to list UST event fields");
 374                 lttng_destroy_handle(handle);
 375                 return size;
 376         }
 377
 378         MSG("UST events:\n-------------");
 379
 380         if (size == 0) {
 381                 MSG("None");
 382         }
 383
 384         for (i = 0; i < size; i++) {
 385                 if (cur_pid != event_field_list[i].event.pid) {
 386                         cur_pid = event_field_list[i].event.pid;
 387                         cmdline = get_cmdline_by_pid(cur_pid);
 388                         MSG("\nPID: %d - Name: %s", cur_pid, cmdline);
 389                         free(cmdline);
 390                 }
 391                 if (strcmp(cur_event.name, event_field_list[i].event.name) != 0) {
 392                         print_events(&event_field_list[i].event);
 393                         memcpy(&cur_event, &event_field_list[i].event,
 394                                 sizeof(cur_event));
 395                 }
 396                 print_event_field(&event_field_list[i]);
 397         }
 398
 399         MSG("");
 400
 401         free(event_field_list);
 402         lttng_destroy_handle(handle);
 403
 404         return CMD_SUCCESS;
 405
 406 error:
 407         lttng_destroy_handle(handle);
 408         return -1;
 409 }
 410
 411 /*
 412  * Ask for all trace events in the kernel and pretty print them.
 413  */
 414 static int list_kernel_events(void)
 415 {
 416         int i, size;
 417         struct lttng_domain domain;
 418         struct lttng_handle *handle;
 419         struct lttng_event *event_list;
 420
 421         memset(&domain, 0, sizeof(domain));
 422
 423         DBG("Getting kernel tracing events");
 424
 425         domain.type = LTTNG_DOMAIN_KERNEL;
 426
 427         handle = lttng_create_handle(NULL, &domain);
 428         if (handle == NULL) {
 429                 goto error;
 430         }
 431
 432         size = lttng_list_tracepoints(handle, &event_list);
 433         if (size < 0) {
 434                 ERR("Unable to list kernel events");
 435                 lttng_destroy_handle(handle);
 436                 return size;
 437         }
 438
 439         MSG("Kernel events:\n-------------");
 440
 441         for (i = 0; i < size; i++) {
 442                 print_events(&event_list[i]);
 443         }
 444
 445         MSG("");
 446
 447         free(event_list);
 448
 449         lttng_destroy_handle(handle);
 450         return CMD_SUCCESS;
 451
 452 error:
 453         lttng_destroy_handle(handle);
 454         return -1;
 455 }
 456
 457 /*
 458  * List events of channel of session and domain.
 459  */
 460 static int list_events(const char *channel_name)
 461 {
 462         int ret, count, i;
 463         struct lttng_event *events = NULL;
 464
 465         count = lttng_list_events(handle, channel_name, &events);
 466         if (count < 0) {
 467                 ret = count;
 468                 goto error;
 469         }
 470
 471         MSG("\n%sEvents:", indent4);
 472         if (count == 0) {
 473                 MSG("%sNone\n", indent6);
 474                 goto end;
 475         }
 476
 477         for (i = 0; i < count; i++) {
 478                 print_events(&events[i]);
 479         }
 480
 481         MSG("");
 482
 483 end:
 484         free(events);
 485         ret = CMD_SUCCESS;
 486
 487 error:
 488         return ret;
 489 }
 490
 491 /*
 492  * Pretty print channel
 493  */
 494 static void print_channel(struct lttng_channel *channel)
 495 {
 496         MSG("- %s:%s\n", channel->name, enabled_string(channel->enabled));
 497
 498         MSG("%sAttributes:", indent4);
 499         MSG("%soverwrite mode: %d", indent6, channel->attr.overwrite);
 500         MSG("%ssubbufers size: %" PRIu64, indent6, channel->attr.subbuf_size);
 501         MSG("%snumber of subbufers: %" PRIu64, indent6, channel->attr.num_subbuf);
 502         MSG("%sswitch timer interval: %u", indent6, channel->attr.switch_timer_interval);
 503         MSG("%sread timer interval: %u", indent6, channel->attr.read_timer_interval);
 504         switch (channel->attr.output) {
 505                 case LTTNG_EVENT_SPLICE:
 506                         MSG("%soutput: splice()", indent6);
 507                         break;
 508                 case LTTNG_EVENT_MMAP:
 509                         MSG("%soutput: mmap()", indent6);
 510                         break;
 511         }
 512 }
 513
 514 /*
 515  * List channel(s) of session and domain.
 516  *
 517  * If channel_name is NULL, all channels are listed.
 518  */
 519 static int list_channels(const char *channel_name)
 520 {
 521         int count, i, ret = CMD_SUCCESS;
 522         unsigned int chan_found = 0;
 523         struct lttng_channel *channels = NULL;
 524
 525         DBG("Listing channel(s) (%s)", channel_name ? : "<all>");
 526
 527         count = lttng_list_channels(handle, &channels);
 528         if (count < 0) {
 529                 switch (-count) {
 530                 case LTTNG_ERR_KERN_CHAN_NOT_FOUND:
 531                         ret = CMD_SUCCESS;
 532                         WARN("No kernel channel");
 533                         break;
 534                 default:
 535                         /* We had a real error */
 536                         ret = count;
 537                         ERR("%s", lttng_strerror(ret));
 538                 }
 539                 goto error_channels;
 540         }
 541
 542         if (channel_name == NULL) {
 543                 MSG("Channels:\n-------------");
 544         }
 545
 546         for (i = 0; i < count; i++) {
 547                 if (channel_name != NULL) {
 548                         if (strncmp(channels[i].name, channel_name, NAME_MAX) == 0) {
 549                                 chan_found = 1;
 550                         } else {
 551                                 continue;
 552                         }
 553                 }
 554                 print_channel(&channels[i]);
 555
 556                 /* Listing events per channel */
 557                 ret = list_events(channels[i].name);
 558                 if (ret < 0) {
 559                         MSG("%s", lttng_strerror(ret));
 560                 }
 561
 562                 if (chan_found) {
 563                         break;
 564                 }
 565         }
 566
 567         if (!chan_found && channel_name != NULL) {
 568                 ERR("Channel %s not found", channel_name);
 569                 goto error;
 570         }
 571
 572         ret = CMD_SUCCESS;
 573
 574 error:
 575         free(channels);
 576
 577 error_channels:
 578         return ret;
 579 }
 580
 581 /*
 582  * List available tracing session. List only basic information.
 583  *
 584  * If session_name is NULL, all sessions are listed.
 585  */
 586 static int list_sessions(const char *session_name)
 587 {
 588         int ret, count, i;
 589         unsigned int session_found = 0;
 590         struct lttng_session *sessions;
 591
 592         count = lttng_list_sessions(&sessions);
 593         DBG("Session count %d", count);
 594         if (count < 0) {
 595                 ret = count;
 596                 ERR("%s", lttng_strerror(ret));
 597                 goto error;
 598         } else if (count == 0) {
 599                 MSG("Currently no available tracing session");
 600                 goto end;
 601         }
 602
 603         if (session_name == NULL) {
 604                 MSG("Available tracing sessions:");
 605         }
 606
 607         for (i = 0; i < count; i++) {
 608                 if (session_name != NULL) {
 609                         if (strncmp(sessions[i].name, session_name, NAME_MAX) == 0) {
 610                                 session_found = 1;
 611                                 MSG("Tracing session %s:%s", session_name, active_string(sessions[i].enabled));
 612                                 MSG("%sTrace path: %s\n", indent4, sessions[i].path);
 613                                 break;
 614                         }
 615                         continue;
 616                 }
 617
 618                 MSG("  %d) %s (%s)%s", i + 1, sessions[i].name, sessions[i].path,
 619                                 active_string(sessions[i].enabled));
 620
 621                 if (session_found) {
 622                         break;
 623                 }
 624         }
 625
 626         free(sessions);
 627
 628         if (!session_found && session_name != NULL) {
 629                 ERR("Session '%s' not found", session_name);
 630                 ret = CMD_ERROR;
 631                 goto error;
 632         }
 633
 634         if (session_name == NULL) {
 635                 MSG("\nUse lttng list <session_name> for more details");
 636         }
 637
 638 end:
 639         return CMD_SUCCESS;
 640
 641 error:
 642         return ret;
 643 }
 644
 645 /*
 646  * List available domain(s) for a session.
 647  */
 648 static int list_domains(const char *session_name)
 649 {
 650         int i, count, ret = CMD_SUCCESS;
 651         struct lttng_domain *domains = NULL;
 652
 653         MSG("Domains:\n-------------");
 654
 655         count = lttng_list_domains(session_name, &domains);
 656         if (count < 0) {
 657                 ret = count;
 658                 goto error;
 659         } else if (count == 0) {
 660                 MSG("  None");
 661                 goto end;
 662         }
 663
 664         for (i = 0; i < count; i++) {
 665                 switch (domains[i].type) {
 666                 case LTTNG_DOMAIN_KERNEL:
 667                         MSG("  - Kernel");
 668                         break;
 669                 case LTTNG_DOMAIN_UST:
 670                         MSG("  - UST global");
 671                         break;
 672                 default:
 673                         break;
 674                 }
 675         }
 676
 677 end:
 678         free(domains);
 679
 680 error:
 681         return ret;
 682 }
 683
 684 /*
 685  * The 'list <options>' first level command
 686  */
 687 int cmd_list(int argc, const char **argv)
 688 {
 689         int opt, ret = CMD_SUCCESS;
 690         const char *session_name;
 691         static poptContext pc;
 692         struct lttng_domain domain;
 693         struct lttng_domain *domains = NULL;
 694
 695         memset(&domain, 0, sizeof(domain));
 696
 697         if (argc < 1) {
 698                 usage(stderr);
 699                 ret = CMD_ERROR;
 700                 goto end;
 701         }
 702
 703         pc = poptGetContext(NULL, argc, argv, long_options, 0);
 704         poptReadDefaultConfig(pc, 0);
 705
 706         while ((opt = poptGetNextOpt(pc)) != -1) {
 707                 switch (opt) {
 708                 case OPT_HELP:
 709                         usage(stdout);
 710                         goto end;
 711                 case OPT_USERSPACE:
 712                         opt_userspace = 1;
 713                         break;
 714                 case OPT_LIST_OPTIONS:
 715                         list_cmd_options(stdout, long_options);
 716                         goto end;
 717                 default:
 718                         usage(stderr);
 719                         ret = CMD_UNDEFINED;
 720                         goto end;
 721                 }
 722         }
 723
 724         /* Get session name (trailing argument) */
 725         session_name = poptGetArg(pc);
 726         DBG2("Session name: %s", session_name);
 727
 728         if (opt_kernel) {
 729                 domain.type = LTTNG_DOMAIN_KERNEL;
 730         } else if (opt_userspace) {
 731                 DBG2("Listing userspace global domain");
 732                 domain.type = LTTNG_DOMAIN_UST;
 733         }
 734
 735         if (opt_kernel || opt_userspace) {
 736                 handle = lttng_create_handle(session_name, &domain);
 737                 if (handle == NULL) {
 738                         ret = CMD_FATAL;
 739                         goto end;
 740                 }
 741         }
 742
 743         if (session_name == NULL) {
 744                 if (!opt_kernel && !opt_userspace) {
 745                         ret = list_sessions(NULL);
 746                         if (ret != 0) {
 747                                 goto end;
 748                         }
 749                 }
 750                 if (opt_kernel) {
 751                         ret = list_kernel_events();
 752                         if (ret < 0) {
 753                                 ret = CMD_ERROR;
 754                                 goto end;
 755                         }
 756                 }
 757                 if (opt_userspace) {
 758                         if (opt_fields) {
 759                                 ret = list_ust_event_fields();
 760                         } else {
 761                                 ret = list_ust_events();
 762                         }
 763                         if (ret < 0) {
 764                                 ret = CMD_ERROR;
 765                                 goto end;
 766                         }
 767                 }
 768         } else {
 769                 /* List session attributes */
 770                 ret = list_sessions(session_name);
 771                 if (ret != 0) {
 772                         goto end;
 773                 }
 774
 775                 /* Domain listing */
 776                 if (opt_domain) {
 777                         ret = list_domains(session_name);
 778                         goto end;
 779                 }
 780
 781                 if (opt_kernel) {
 782                         /* Channel listing */
 783                         ret = list_channels(opt_channel);
 784                         if (ret < 0) {
 785                                 goto end;
 786                         }
 787                 } else {
 788                         int i, nb_domain;
 789
 790                         /* We want all domain(s) */
 791                         nb_domain = lttng_list_domains(session_name, &domains);
 792                         if (nb_domain < 0) {
 793                                 ret = nb_domain;
 794                                 goto end;
 795                         }
 796
 797                         for (i = 0; i < nb_domain; i++) {
 798                                 switch (domains[i].type) {
 799                                 case LTTNG_DOMAIN_KERNEL:
 800                                         MSG("=== Domain: Kernel ===\n");
 801                                         break;
 802                                 case LTTNG_DOMAIN_UST:
 803                                         MSG("=== Domain: UST global ===\n");
 804                                         break;
 805                                 default:
 806                                         MSG("=== Domain: Unimplemented ===\n");
 807                                         break;
 808                                 }
 809
 810                                 /* Clean handle before creating a new one */
 811                                 if (handle) {
 812                                         lttng_destroy_handle(handle);
 813                                 }
 814
 815                                 handle = lttng_create_handle(session_name, &domains[i]);
 816                                 if (handle == NULL) {
 817                                         ret = CMD_FATAL;
 818                                         goto end;
 819                                 }
 820
 821                                 ret = list_channels(opt_channel);
 822                                 if (ret < 0) {
 823                                         goto end;
 824                                 }
 825                         }
 826                 }
 827         }
 828
 829 end:
 830         free(domains);
 831         if (handle) {
 832                 lttng_destroy_handle(handle);
 833         }
 834
 835         poptFreeContext(pc);
 836         return ret;
 837 }