src/bin/lttng/commands/snapshot.c

   1 /*
   2  * Copyright (C) 2013 - David Goulet <dgoulet@efficios.com>
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU General Public License, version 2 only, as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; if not, write to the Free Software Foundation, Inc., 51
  15  * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  16  */
  17
  18 #define _LGPL_SOURCE
  19 #include <assert.h>
  20 #include <inttypes.h>
  21 #include <popt.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <sys/stat.h>
  26 #include <sys/types.h>
  27 #include <unistd.h>
  28 #include <assert.h>
  29
  30 #include <common/utils.h>
  31 #include <common/mi-lttng.h>
  32 #include <lttng/snapshot.h>
  33
  34 #include "../command.h"
  35
  36 static const char *opt_session_name;
  37 static const char *opt_output_name;
  38 static const char *opt_data_url;
  39 static const char *opt_ctrl_url;
  40 static const char *current_session_name;
  41 static uint64_t opt_max_size;
  42
  43 /* Stub for the cmd struct actions. */
  44 static int cmd_add_output(int argc, const char **argv);
  45 static int cmd_del_output(int argc, const char **argv);
  46 static int cmd_list_output(int argc, const char **argv);
  47 static int cmd_record(int argc, const char **argv);
  48
  49 static const char *indent4 = "    ";
  50
  51 #ifdef LTTNG_EMBED_HELP
  52 static const char help_msg[] =
  53 #include <lttng-snapshot.1.h>
  54 ;
  55 #endif
  56
  57 enum {
  58         OPT_HELP = 1,
  59         OPT_LIST_OPTIONS,
  60         OPT_MAX_SIZE,
  61         OPT_LIST_COMMANDS,
  62 };
  63
  64 static struct mi_writer *writer;
  65
  66 static struct poptOption snapshot_opts[] = {
  67         /* longName, shortName, argInfo, argPtr, value, descrip, argDesc */
  68         {"help",      'h', POPT_ARG_NONE, 0, OPT_HELP, 0, 0},
  69         {"session",      's', POPT_ARG_STRING, &opt_session_name, 0, 0, 0},
  70         {"ctrl-url",     'C', POPT_ARG_STRING, &opt_ctrl_url, 0, 0, 0},
  71         {"data-url",     'D', POPT_ARG_STRING, &opt_data_url, 0, 0, 0},
  72         {"name",         'n', POPT_ARG_STRING, &opt_output_name, 0, 0, 0},
  73         {"max-size",     'm', POPT_ARG_STRING, 0, OPT_MAX_SIZE, 0, 0},
  74         {"list-options",   0, POPT_ARG_NONE, NULL, OPT_LIST_OPTIONS, NULL, NULL},
  75         {"list-commands",  0, POPT_ARG_NONE, NULL, OPT_LIST_COMMANDS},
  76         {0, 0, 0, 0, 0, 0, 0}
  77 };
  78
  79 static struct cmd_struct actions[] = {
  80         { "add-output", cmd_add_output },
  81         { "del-output", cmd_del_output },
  82         { "list-output", cmd_list_output },
  83         { "record", cmd_record },
  84         { NULL, NULL }  /* Array closure */
  85 };
  86
  87 /*
  88  * Count and return the number of arguments in argv.
  89  */
  90 static int count_arguments(const char **argv)
  91 {
  92         int i = 0;
  93
  94         assert(argv);
  95
  96         while (argv[i] != NULL) {
  97                 i++;
  98         }
  99
 100         return i;
 101 }
 102
 103 /*
 104  * Create a snapshot output object from arguments using the given URL.
 105  *
 106  * Return a newly allocated object or NULL on error.
 107  */
 108 static struct lttng_snapshot_output *create_output_from_args(const char *url)
 109 {
 110         int ret = 0;
 111         struct lttng_snapshot_output *output = NULL;
 112
 113         output = lttng_snapshot_output_create();
 114         if (!output) {
 115                 goto error_create;
 116         }
 117
 118         if (url) {
 119                 ret = lttng_snapshot_output_set_ctrl_url(url, output);
 120                 if (ret < 0) {
 121                         goto error;
 122                 }
 123         } else if (opt_ctrl_url) {
 124                 ret = lttng_snapshot_output_set_ctrl_url(opt_ctrl_url, output);
 125                 if (ret < 0) {
 126                         goto error;
 127                 }
 128         }
 129
 130         if (opt_data_url) {
 131                 ret = lttng_snapshot_output_set_data_url(opt_data_url, output);
 132                 if (ret < 0) {
 133                         goto error;
 134                 }
 135         }
 136
 137         if (opt_max_size) {
 138                 ret = lttng_snapshot_output_set_size(opt_max_size, output);
 139                 if (ret < 0) {
 140                         goto error;
 141                 }
 142         }
 143
 144         if (opt_output_name) {
 145                 ret = lttng_snapshot_output_set_name(opt_output_name, output);
 146                 if (ret < 0) {
 147                         goto error;
 148                 }
 149         }
 150
 151         return output;
 152
 153 error:
 154         lttng_snapshot_output_destroy(output);
 155 error_create:
 156         return NULL;
 157 }
 158
 159 static int list_output(void)
 160 {
 161         int ret, output_seen = 0;
 162         struct lttng_snapshot_output *s_iter;
 163         struct lttng_snapshot_output_list *list;
 164
 165         ret = lttng_snapshot_list_output(current_session_name, &list);
 166         if (ret < 0) {
 167                 goto error;
 168         }
 169
 170         MSG("Snapshot output list for session %s", current_session_name);
 171
 172         if (lttng_opt_mi) {
 173                 ret = mi_lttng_snapshot_output_session_name(writer,
 174                                 current_session_name);
 175                 if (ret) {
 176                         ret = CMD_ERROR;
 177                         goto end;
 178                 }
 179         }
 180
 181         while ((s_iter = lttng_snapshot_output_list_get_next(list)) != NULL) {
 182                 if (lttng_snapshot_output_get_maxsize(s_iter)) {
 183                         MSG("%s[%" PRIu32 "] %s: %s (max size: %" PRIu64 " bytes)", indent4,
 184                                         lttng_snapshot_output_get_id(s_iter),
 185                                         lttng_snapshot_output_get_name(s_iter),
 186                                         lttng_snapshot_output_get_ctrl_url(s_iter),
 187                                         lttng_snapshot_output_get_maxsize(s_iter));
 188                 } else {
 189                         MSG("%s[%" PRIu32 "] %s: %s", indent4,
 190                                         lttng_snapshot_output_get_id(s_iter),
 191                                         lttng_snapshot_output_get_name(s_iter),
 192                                         lttng_snapshot_output_get_ctrl_url(s_iter));
 193                 }
 194                 output_seen = 1;
 195                 if (lttng_opt_mi) {
 196                         ret = mi_lttng_snapshot_list_output(writer, s_iter);
 197                         if (ret) {
 198                                 ret = CMD_ERROR;
 199                                 goto end;
 200                         }
 201                 }
 202         }
 203
 204         if (lttng_opt_mi) {
 205                 /* Close snapshot snapshots element */
 206                 ret = mi_lttng_writer_close_element(writer);
 207                 if (ret) {
 208                         ret = CMD_ERROR;
 209                         goto end;
 210                 }
 211
 212                 /* Close snapshot session element */
 213                 ret = mi_lttng_writer_close_element(writer);
 214                 if (ret) {
 215                         ret = CMD_ERROR;
 216                 }
 217         }
 218 end:
 219         lttng_snapshot_output_list_destroy(list);
 220
 221         if (!output_seen) {
 222                 MSG("%sNone", indent4);
 223         }
 224
 225 error:
 226         return ret;
 227 }
 228
 229 /*
 230  * Delete output by ID.
 231  */
 232 static int del_output(uint32_t id, const char *name)
 233 {
 234         int ret;
 235         struct lttng_snapshot_output *output = NULL;
 236
 237         output = lttng_snapshot_output_create();
 238         if (!output) {
 239                 ret = CMD_FATAL;
 240                 goto error;
 241         }
 242
 243         if (name) {
 244                 ret = lttng_snapshot_output_set_name(name, output);
 245         } else if (id != UINT32_MAX) {
 246                 ret = lttng_snapshot_output_set_id(id, output);
 247         } else {
 248                 ret = CMD_ERROR;
 249                 goto error;
 250         }
 251         if (ret < 0) {
 252                 ret = CMD_FATAL;
 253                 goto error;
 254         }
 255
 256         ret = lttng_snapshot_del_output(current_session_name, output);
 257         if (ret < 0) {
 258                 goto error;
 259         }
 260
 261         if (id != UINT32_MAX) {
 262                 MSG("Snapshot output id %" PRIu32 " successfully deleted for session %s",
 263                                 id, current_session_name);
 264         } else {
 265                 MSG("Snapshot output %s successfully deleted for session %s",
 266                                 name, current_session_name);
 267         }
 268
 269         if (lttng_opt_mi) {
 270                 ret = mi_lttng_snapshot_del_output(writer, id, name,
 271                                 current_session_name);
 272                 if (ret) {
 273                         ret = CMD_ERROR;
 274                 }
 275         }
 276
 277 error:
 278         lttng_snapshot_output_destroy(output);
 279         return ret;
 280 }
 281
 282 /*
 283  * Add output from the user URL.
 284  */
 285 static int add_output(const char *url)
 286 {
 287         int ret;
 288         struct lttng_snapshot_output *output = NULL;
 289         char name[NAME_MAX];
 290         const char *n_ptr;
 291
 292         if (!url && (!opt_data_url || !opt_ctrl_url)) {
 293                 ret = CMD_ERROR;
 294                 goto error;
 295         }
 296
 297         output = create_output_from_args(url);
 298         if (!output) {
 299                 ret = CMD_FATAL;
 300                 goto error;
 301         }
 302
 303         /* This call, if successful, populates the id of the output object. */
 304         ret = lttng_snapshot_add_output(current_session_name, output);
 305         if (ret < 0) {
 306                 goto error;
 307         }
 308
 309         n_ptr = lttng_snapshot_output_get_name(output);
 310         if (*n_ptr == '\0') {
 311                 int pret;
 312                 pret = snprintf(name, sizeof(name), DEFAULT_SNAPSHOT_NAME "-%" PRIu32,
 313                                 lttng_snapshot_output_get_id(output));
 314                 if (pret < 0) {
 315                         PERROR("snprintf add output name");
 316                 }
 317                 n_ptr = name;
 318         }
 319
 320         MSG("Snapshot output successfully added for session %s",
 321                         current_session_name);
 322         if (opt_max_size) {
 323                 MSG("  [%" PRIu32 "] %s: %s (max size: %" PRIu64 " bytes)",
 324                                 lttng_snapshot_output_get_id(output), n_ptr,
 325                                 lttng_snapshot_output_get_ctrl_url(output),
 326                                 lttng_snapshot_output_get_maxsize(output));
 327         } else {
 328                 MSG("  [%" PRIu32 "] %s: %s",
 329                                 lttng_snapshot_output_get_id(output), n_ptr,
 330                                 lttng_snapshot_output_get_ctrl_url(output));
 331         }
 332         if (lttng_opt_mi) {
 333                 ret = mi_lttng_snapshot_add_output(writer, current_session_name,
 334                                 n_ptr, output);
 335                 if (ret) {
 336                         ret = CMD_ERROR;
 337                 }
 338         }
 339 error:
 340         lttng_snapshot_output_destroy(output);
 341         return ret;
 342 }
 343
 344 static int cmd_add_output(int argc, const char **argv)
 345 {
 346         int ret;
 347
 348         if (argc < 2 && (!opt_data_url || !opt_ctrl_url)) {
 349                 ERR("An output destination must be specified to add a snapshot output.");
 350                 ret = CMD_ERROR;
 351                 goto end;
 352         }
 353
 354         ret = add_output(argv[1]);
 355         if (ret < 0) {
 356                 switch (-ret) {
 357                 case LTTNG_ERR_SNAPSHOT_UNSUPPORTED:
 358                         ERR("Session \"%s\" contains a channel that is incompatible with the snapshot functionality.\nMake sure all channels are configured in 'mmap' output mode.",
 359                                         current_session_name);
 360                         ret = CMD_ERROR;
 361                         break;
 362                 default:
 363                         break;
 364                 }
 365         }
 366
 367 end:
 368         return ret;
 369 }
 370
 371 static int cmd_del_output(int argc, const char **argv)
 372 {
 373         int ret;
 374         char *name;
 375         long id;
 376
 377         if (argc < 2) {
 378                 ERR("A snapshot output name or id must be provided to delete a snapshot output.");
 379                 ret = CMD_ERROR;
 380                 goto end;
 381         }
 382
 383         errno = 0;
 384         id = strtol(argv[1], &name, 10);
 385         if (id == 0 && (errno == 0 || errno == EINVAL)) {
 386                 ret = del_output(UINT32_MAX, name);
 387         } else if (errno == 0 && *name == '\0') {
 388                 ret = del_output(id, NULL);
 389         } else {
 390                 ERR("Argument %s not recognized", argv[1]);
 391                 ret = -1;
 392                 goto end;
 393         }
 394
 395 end:
 396         return ret;
 397 }
 398
 399 static int cmd_list_output(int argc, const char **argv)
 400 {
 401         int ret;
 402
 403         ret = list_output();
 404
 405         return ret;
 406 }
 407
 408 /*
 409  * Do a snapshot record with the URL if one is given.
 410  */
 411 static int record(const char *url)
 412 {
 413         int ret;
 414         struct lttng_snapshot_output *output = NULL;
 415
 416         output = create_output_from_args(url);
 417         if (!output) {
 418                 ret = CMD_FATAL;
 419                 goto error;
 420         }
 421
 422         ret = lttng_snapshot_record(current_session_name, output, 0);
 423         if (ret < 0) {
 424                 if (ret == -LTTNG_ERR_MAX_SIZE_INVALID) {
 425                         ERR("Invalid snapshot size. Cannot fit at least one packet per stream.");
 426                 }
 427                 goto error;
 428         }
 429
 430         MSG("Snapshot recorded successfully for session %s", current_session_name);
 431
 432         if (url) {
 433                 MSG("Snapshot written at: %s", url);
 434         } else if (opt_ctrl_url) {
 435                 MSG("Snapshot written to ctrl: %s, data: %s", opt_ctrl_url,
 436                                 opt_data_url);
 437         }
 438
 439         if (lttng_opt_mi) {
 440                 ret = mi_lttng_snapshot_record(writer, current_session_name, url,
 441                                 opt_ctrl_url, opt_data_url);
 442                 if (ret) {
 443                         ret = CMD_ERROR;
 444                 }
 445         }
 446
 447 error:
 448         lttng_snapshot_output_destroy(output);
 449         return ret;
 450 }
 451
 452 static int cmd_record(int argc, const char **argv)
 453 {
 454         int ret;
 455
 456         if (argc == 2) {
 457                 ret = record(argv[1]);
 458         } else {
 459                 ret = record(NULL);
 460         }
 461
 462         return ret;
 463 }
 464
 465 static enum cmd_error_code handle_command(const char **argv)
 466 {
 467         int mi_ret, i = 0, argc;
 468         enum cmd_error_code cmd_ret;
 469         struct cmd_struct *cmd;
 470
 471         if (!argv) {
 472                 ERR("No action specified for snapshot command.");
 473                 cmd_ret = CMD_ERROR;
 474                 goto end;
 475         }
 476
 477         if ((!opt_ctrl_url && opt_data_url) ||
 478                         (opt_ctrl_url && !opt_data_url)) {
 479                 ERR("URLs must be specified for both data and control");
 480                 cmd_ret = CMD_ERROR;
 481                 goto end;
 482         }
 483
 484         argc = count_arguments(argv);
 485         /* popt should have passed NULL if no arguments are present. */
 486         assert(argc > 0);
 487
 488         cmd = &actions[i];
 489         while (cmd->func != NULL) {
 490                 /* Find command */
 491                 if (strcmp(argv[0], cmd->name) == 0) {
 492                         int result;
 493
 494                         if (lttng_opt_mi) {
 495                                 /* Action element */
 496                                 mi_ret = mi_lttng_writer_open_element(writer,
 497                                                 mi_lttng_element_command_action);
 498                                 if (mi_ret) {
 499                                         cmd_ret = CMD_ERROR;
 500                                         goto end;
 501                                 }
 502
 503                                 /* Name of the action */
 504                                 mi_ret = mi_lttng_writer_write_element_string(writer,
 505                                                 config_element_name, argv[0]);
 506                                 if (mi_ret) {
 507                                         cmd_ret = CMD_ERROR;
 508                                         goto end;
 509                                 }
 510
 511                                 /* Open output element */
 512                                 mi_ret = mi_lttng_writer_open_element(writer,
 513                                                 mi_lttng_element_command_output);
 514                                 if (mi_ret) {
 515                                         cmd_ret = CMD_ERROR;
 516                                         goto end;
 517                                 }
 518                         }
 519
 520                         result = cmd->func(argc, argv);
 521                         if (result) {
 522                                 switch (result) {
 523                                 case CMD_ERROR:
 524                                 case CMD_UNDEFINED:
 525                                 case CMD_FATAL:
 526                                 case CMD_WARNING:
 527                                 case CMD_UNSUPPORTED:
 528                                         /*
 529                                          * Sub-commands mix lttng_error_codes
 530                                          * and cmd_error_codes. This should be
 531                                          * cleaned-up, but in the meantime this
 532                                          * hack works since the values of the
 533                                          * two enums do not intersect.
 534                                          */
 535                                         cmd_ret = result;
 536                                         break;
 537                                 case -LTTNG_ERR_SNAPSHOT_NODATA:
 538                                         WARN("%s", lttng_strerror(result));
 539
 540                                         /*  A warning is fine since the user has no control on
 541                                          *  whether or not applications (or the kernel) have
 542                                          *  produced any event between the start of the tracing
 543                                          *  session and the recording of the snapshot. MI wise
 544                                          *  the command is not a success since nothing was
 545                                          *  recorded.
 546                                          */
 547                                         cmd_ret = CMD_SUCCESS;
 548                                         break;
 549                                 default:
 550                                         ERR("%s", lttng_strerror(result));
 551                                         cmd_ret = CMD_ERROR;
 552                                         break;
 553                                 }
 554                         } else {
 555                                 cmd_ret = CMD_SUCCESS;
 556                         }
 557
 558
 559                         if (lttng_opt_mi) {
 560                                 /* Close output and action element */
 561                                 mi_ret = mi_lttng_close_multi_element(writer, 2);
 562                                 if (mi_ret) {
 563                                         cmd_ret = CMD_ERROR;
 564                                         goto end;
 565                                 }
 566                         }
 567                         goto end;
 568                 }
 569                 i++;
 570                 cmd = &actions[i];
 571         }
 572
 573         cmd_ret = CMD_UNDEFINED;
 574
 575 end:
 576         return cmd_ret;
 577 }
 578 /*
 579  * The 'snapshot <cmd> <options>' first level command
 580  */
 581 int cmd_snapshot(int argc, const char **argv)
 582 {
 583         int opt;
 584         int mi_ret;
 585         enum cmd_error_code cmd_ret = CMD_SUCCESS;
 586         char *session_name = NULL;
 587         static poptContext pc;
 588
 589         pc = poptGetContext(NULL, argc, argv, snapshot_opts, 0);
 590         poptReadDefaultConfig(pc, 0);
 591
 592         /* Mi check */
 593         if (lttng_opt_mi) {
 594                 writer = mi_lttng_writer_create(fileno(stdout), lttng_opt_mi);
 595                 if (!writer) {
 596                         cmd_ret = CMD_ERROR;
 597                         goto end;
 598                 }
 599
 600                 /* Open command element */
 601                 mi_ret = mi_lttng_writer_command_open(writer,
 602                                 mi_lttng_element_command_snapshot);
 603                 if (mi_ret) {
 604                         cmd_ret = CMD_ERROR;
 605                         goto end;
 606                 }
 607
 608                 /* Open output element */
 609                 mi_ret = mi_lttng_writer_open_element(writer,
 610                                 mi_lttng_element_command_output);
 611                 if (mi_ret) {
 612                         cmd_ret = CMD_ERROR;
 613                         goto end;
 614                 }
 615         }
 616
 617         while ((opt = poptGetNextOpt(pc)) != -1) {
 618                 switch (opt) {
 619                 case OPT_HELP:
 620                 {
 621                         int ret;
 622
 623                         /* SHOW_HELP assigns to ret. */
 624                         SHOW_HELP();
 625                         cmd_ret = ret;
 626                         goto end;
 627                 }
 628                 case OPT_LIST_OPTIONS:
 629                         list_cmd_options(stdout, snapshot_opts);
 630                         goto end;
 631                 case OPT_LIST_COMMANDS:
 632                         list_commands(actions, stdout);
 633                         goto end;
 634                 case OPT_MAX_SIZE:
 635                 {
 636                         uint64_t val;
 637                         const char *opt = poptGetOptArg(pc);
 638
 639                         if (utils_parse_size_suffix((char *) opt, &val) < 0) {
 640                                 ERR("Unable to handle max-size value %s", opt);
 641                                 cmd_ret = CMD_ERROR;
 642                                 goto end;
 643                         }
 644
 645                         opt_max_size = val;
 646
 647                         break;
 648                 }
 649                 default:
 650                         cmd_ret = CMD_UNDEFINED;
 651                         goto end;
 652                 }
 653         }
 654
 655         if (!opt_session_name) {
 656                 session_name = get_session_name();
 657                 if (session_name == NULL) {
 658                         cmd_ret = CMD_ERROR;
 659                         goto end;
 660                 }
 661                 current_session_name = session_name;
 662         } else {
 663                 current_session_name = opt_session_name;
 664         }
 665
 666         cmd_ret = handle_command(poptGetArgs(pc));
 667
 668         if (lttng_opt_mi) {
 669                 /* Close output element */
 670                 mi_ret = mi_lttng_writer_close_element(writer);
 671                 if (mi_ret) {
 672                         cmd_ret = CMD_ERROR;
 673                         goto end;
 674                 }
 675
 676                 /* Success ? */
 677                 mi_ret = mi_lttng_writer_write_element_bool(writer,
 678                                 mi_lttng_element_command_success,
 679                                 cmd_ret == CMD_SUCCESS);
 680                 if (mi_ret) {
 681                         cmd_ret = CMD_ERROR;
 682                         goto end;
 683                 }
 684
 685                 /* Command element close */
 686                 mi_ret = mi_lttng_writer_command_close(writer);
 687                 if (mi_ret) {
 688                         cmd_ret = CMD_ERROR;
 689                         goto end;
 690                 }
 691         }
 692
 693 end:
 694         /* Mi clean-up */
 695         if (writer && mi_lttng_writer_destroy(writer)) {
 696                 cmd_ret = CMD_ERROR;
 697         }
 698
 699         if (!opt_session_name) {
 700                 free(session_name);
 701         }
 702
 703         poptFreeContext(pc);
 704         return cmd_ret;
 705 }