src/bin/lttng/lttng.cpp

   1 /*
   2  * Copyright (C) 2011 EfficiOS Inc.
   3  *
   4  * SPDX-License-Identifier: GPL-2.0-only
   5  *
   6  */
   7
   8 #define _LGPL_SOURCE
   9 #include <getopt.h>
  10 #include <signal.h>
  11 #include <stdio.h>
  12 #include <stdlib.h>
  13 #include <string.h>
  14 #include <sys/types.h>
  15 #include <sys/wait.h>
  16 #include <unistd.h>
  17 #include <ctype.h>
  18
  19 #include <lttng/lttng.h>
  20 #include <common/error.hpp>
  21 #include <common/compat/getenv.hpp>
  22 #include <common/utils.hpp>
  23
  24 #include "command.hpp"
  25 #include "version.hpp"
  26
  27 static const char *help_msg =
  28 #ifdef LTTNG_EMBED_HELP
  29 #include <lttng.1.h>
  30 #else
  31 NULL
  32 #endif
  33 ;
  34
  35 /* Variables */
  36 static const char *progname;
  37 int opt_no_sessiond;
  38 char *opt_sessiond_path;
  39
  40 char *opt_relayd_path;
  41
  42 enum {
  43         OPT_RELAYD_PATH,
  44         OPT_SESSION_PATH,
  45         OPT_DUMP_OPTIONS,
  46         OPT_DUMP_COMMANDS,
  47 };
  48
  49 /* Getopt options. No first level command. */
  50 static struct option long_options[] = {
  51         {"version",          0, NULL, 'V'},
  52         {"help",             0, NULL, 'h'},
  53         {"group",            1, NULL, 'g'},
  54         {"verbose",          0, NULL, 'v'},
  55         {"quiet",            0, NULL, 'q'},
  56         {"mi",               1, NULL, 'm'},
  57         {"no-sessiond",      0, NULL, 'n'},
  58         {"sessiond-path",    1, NULL, OPT_SESSION_PATH},
  59         {"relayd-path",      1, NULL, OPT_RELAYD_PATH},
  60         {"list-options",     0, NULL, OPT_DUMP_OPTIONS},
  61         {"list-commands",    0, NULL, OPT_DUMP_COMMANDS},
  62         {NULL, 0, NULL, 0}
  63 };
  64
  65 /* First level command */
  66 static struct cmd_struct commands[] =  {
  67         { "add-context", cmd_add_context},
  68         { "add-trigger", cmd_add_trigger},
  69         { "create", cmd_create},
  70         { "clear", cmd_clear},
  71         { "destroy", cmd_destroy},
  72         { "disable-channel", cmd_disable_channels},
  73         { "disable-event", cmd_disable_events},
  74         { "enable-channel", cmd_enable_channels},
  75         { "enable-event", cmd_enable_events},
  76         { "help", NULL},
  77         { "list", cmd_list},
  78         { "list-triggers", cmd_list_triggers},
  79         { "load", cmd_load},
  80         { "metadata", cmd_metadata},
  81         { "regenerate", cmd_regenerate},
  82         { "remove-trigger", cmd_remove_trigger},
  83         { "rotate", cmd_rotate},
  84         { "enable-rotation", cmd_enable_rotation},
  85         { "disable-rotation", cmd_disable_rotation},
  86         { "save", cmd_save},
  87         { "set-session", cmd_set_session},
  88         { "snapshot", cmd_snapshot},
  89         { "start", cmd_start},
  90         { "status", cmd_status},
  91         { "stop", cmd_stop},
  92         { "track", cmd_track},
  93         { "untrack", cmd_untrack},
  94         { "version", cmd_version},
  95         { "view", cmd_view},
  96         { NULL, NULL}   /* Array closure */
  97 };
  98
  99 static void version(FILE *ofp)
 100 {
 101         fprintf(ofp, "%s (LTTng Trace Control) " VERSION" - " VERSION_NAME "%s%s\n",
 102                         progname,
 103                         GIT_VERSION[0] == '\0' ? "" : " - " GIT_VERSION,
 104                         EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " EXTRA_VERSION_NAME);
 105 }
 106
 107 /*
 108  * Find the MI output type enum from a string. This function is for the support
 109  * of machine interface output.
 110  */
 111 static int mi_output_type(const char *output_type)
 112 {
 113         int ret = 0;
 114
 115         if (!strncasecmp("xml", output_type, 3)) {
 116                 ret = LTTNG_MI_XML;
 117         } else {
 118                 /* Invalid output format */
 119                 ERR("MI output format not supported");
 120                 ret = -LTTNG_ERR_MI_OUTPUT_TYPE;
 121         }
 122
 123         return ret;
 124 }
 125
 126 /*
 127  *  list_options
 128  *
 129  *  List options line by line. This is mostly for bash auto completion and to
 130  *  avoid difficult parsing.
 131  */
 132 static void list_options(FILE *ofp)
 133 {
 134         int i = 0;
 135         struct option *option = NULL;
 136
 137         option = &long_options[i];
 138         while (option->name != NULL) {
 139                 fprintf(ofp, "--%s\n", option->name);
 140
 141                 if (isprint(option->val)) {
 142                         fprintf(ofp, "-%c\n", option->val);
 143                 }
 144
 145                 i++;
 146                 option = &long_options[i];
 147         }
 148 }
 149
 150 /*
 151  * clean_exit
 152  */
 153 __attribute__((noreturn))
 154 static void clean_exit(int code)
 155 {
 156         DBG("Clean exit");
 157         exit(code);
 158 }
 159
 160 /*
 161  *  sighandler
 162  *
 163  *  Signal handler for the daemon
 164  */
 165 static void sighandler(int sig)
 166 {
 167         switch (sig) {
 168                 case SIGTERM:
 169                         DBG("SIGTERM caught");
 170                         clean_exit(EXIT_FAILURE);
 171                         break;
 172                 default:
 173                         DBG("Unknown signal %d caught", sig);
 174                         break;
 175         }
 176
 177         return;
 178 }
 179
 180 /*
 181  *  set_signal_handler
 182  *
 183  *  Setup signal handler for SIGCHLD and SIGTERM.
 184  */
 185 static int set_signal_handler(void)
 186 {
 187         int ret = 0;
 188         struct sigaction sa;
 189         sigset_t sigset;
 190
 191         if ((ret = sigemptyset(&sigset)) < 0) {
 192                 PERROR("sigemptyset");
 193                 goto end;
 194         }
 195
 196         sa.sa_handler = sighandler;
 197         sa.sa_mask = sigset;
 198         sa.sa_flags = 0;
 199
 200         if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
 201                 PERROR("sigaction");
 202                 goto end;
 203         }
 204
 205 end:
 206         return ret;
 207 }
 208
 209 /*
 210  *  handle_command
 211  *
 212  *  Handle the full argv list of a first level command. Will find the command
 213  *  in the global commands array and call the function callback associated.
 214  *
 215  *  If command not found, return -1
 216  *  else, return function command error code.
 217  */
 218 static int handle_command(int argc, char **argv)
 219 {
 220         int i = 0, ret;
 221         struct cmd_struct *cmd;
 222
 223         if (*argv == NULL) {
 224                 ret = CMD_SUCCESS;
 225                 goto end;
 226         }
 227
 228         /* Special case for help command which needs the commands array */
 229         if (strcmp(argv[0], "help") == 0) {
 230                 ret = cmd_help(argc, (const char**) argv, commands);
 231                 goto end;
 232         }
 233
 234         cmd = &commands[i];
 235         while (cmd->name != NULL) {
 236                 /* Find command */
 237                 if (strcmp(argv[0], cmd->name) == 0) {
 238                         ret = cmd->func(argc, (const char**) argv);
 239                         goto end;
 240                 }
 241                 i++;
 242                 cmd = &commands[i];
 243         }
 244
 245         /* Command not found */
 246         ret = CMD_UNDEFINED;
 247
 248 end:
 249         return ret;
 250 }
 251
 252 static bool command_exists(const char *command)
 253 {
 254         const struct cmd_struct *cmd = commands;
 255         bool exists = false;
 256
 257         while (cmd->name != NULL) {
 258                 if (!strcmp(command, cmd->name)) {
 259                         exists = true;
 260                         goto end;
 261                 }
 262                 cmd++;
 263         }
 264
 265 end:
 266         return exists;
 267 }
 268
 269 static void show_basic_help(void)
 270 {
 271         puts("Usage: lttng [--group=GROUP] [--mi=TYPE] [--no-sessiond | --sessiond-path=PATH]");
 272         puts("             [--quiet | -v | -vv | -vvv] COMMAND [COMMAND OPTIONS]");
 273         puts("");
 274         puts("Available commands:");
 275         puts("");
 276         puts("Recording sessions:");
 277         puts("  create            " CONFIG_CMD_DESCR_CREATE);
 278         puts("  clear             " CONFIG_CMD_DESCR_CLEAR);
 279         puts("  destroy           " CONFIG_CMD_DESCR_DESTROY);
 280         puts("  load              " CONFIG_CMD_DESCR_LOAD);
 281         puts("  regenerate        " CONFIG_CMD_DESCR_REGENERATE);
 282         puts("  save              " CONFIG_CMD_DESCR_SAVE);
 283         puts("  set-session       " CONFIG_CMD_DESCR_SET_SESSION);
 284         puts("");
 285         puts("Channels:");
 286         puts("  add-context       " CONFIG_CMD_DESCR_ADD_CONTEXT);
 287         puts("  disable-channel   " CONFIG_CMD_DESCR_DISABLE_CHANNEL);
 288         puts("  enable-channel    " CONFIG_CMD_DESCR_ENABLE_CHANNEL);
 289         puts("");
 290         puts("Recording event rules:");
 291         puts("  disable-event     " CONFIG_CMD_DESCR_DISABLE_EVENT);
 292         puts("  enable-event      " CONFIG_CMD_DESCR_ENABLE_EVENT);
 293         puts("");
 294         puts("Status:");
 295         puts("  list              " CONFIG_CMD_DESCR_LIST);
 296         puts("  status            " CONFIG_CMD_DESCR_STATUS);
 297         puts("");
 298         puts("Control:");
 299         puts("  snapshot          " CONFIG_CMD_DESCR_SNAPSHOT);
 300         puts("  start             " CONFIG_CMD_DESCR_START);
 301         puts("  stop              " CONFIG_CMD_DESCR_STOP);
 302         puts("");
 303         puts("Recording session rotation:");
 304         puts("  disable-rotation  " CONFIG_CMD_DESCR_DISABLE_ROTATION);
 305         puts("  enable-rotation   " CONFIG_CMD_DESCR_ENABLE_ROTATION);
 306         puts("  rotate            " CONFIG_CMD_DESCR_ROTATE);
 307         puts("");
 308         puts("Resource tracking:");
 309         puts("  track             " CONFIG_CMD_DESCR_TRACK);
 310         puts("  untrack           " CONFIG_CMD_DESCR_UNTRACK);
 311         puts("");
 312         puts("Triggers:");
 313         puts("  add-trigger       " CONFIG_CMD_DESCR_ADD_TRIGGER);
 314         puts("  remove-trigger    " CONFIG_CMD_DESCR_REMOVE_TRIGGER);
 315         puts("  list-triggers     " CONFIG_CMD_DESCR_LIST_TRIGGERS);
 316         puts("");
 317         puts("Miscellaneous:");
 318         puts("  help              " CONFIG_CMD_DESCR_HELP);
 319         puts("  version           " CONFIG_CMD_DESCR_VERSION);
 320         puts("  view              " CONFIG_CMD_DESCR_VIEW);
 321         puts("");
 322         puts("Run `lttng help COMMAND` or `lttng COMMAND --help` to get help with");
 323         puts("command COMMAND.");
 324         puts("");
 325         puts("See `man lttng` for more help with the lttng command.");
 326 }
 327
 328 /*
 329  * Parse command line arguments.
 330  *
 331  * Return 0 if OK, else -1
 332  */
 333 static int parse_args(int argc, char **argv)
 334 {
 335         int opt, ret;
 336
 337         if (lttng_is_setuid_setgid()) {
 338                 ERR("'%s' is not allowed to be executed as a setuid/setgid binary for security reasons. Aborting.", argv[0]);
 339                 clean_exit(EXIT_FAILURE);
 340         }
 341
 342         if (argc < 2) {
 343                 show_basic_help();
 344                 clean_exit(EXIT_FAILURE);
 345         }
 346
 347         while ((opt = getopt_long(argc, argv, "+Vhnvqg:m:", long_options, NULL)) != -1) {
 348                 switch (opt) {
 349                 case 'V':
 350                         version(stdout);
 351                         ret = 0;
 352                         goto end;
 353                 case 'h':
 354                         ret = utils_show_help(1, "lttng", help_msg);
 355                         if (ret) {
 356                                 ERR("Cannot show --help for `lttng`");
 357                                 perror("exec");
 358                         }
 359                         goto end;
 360                 case 'v':
 361                         /* There is only 3 possible level of verbosity. (-vvv) */
 362                         if (lttng_opt_verbose < 3) {
 363                                 lttng_opt_verbose += 1;
 364                         }
 365                         break;
 366                 case 'q':
 367                         lttng_opt_quiet = 1;
 368                         break;
 369                 case 'm':
 370                         lttng_opt_mi = mi_output_type(optarg);
 371                         if (lttng_opt_mi < 0) {
 372                                 ret = lttng_opt_mi;
 373                                 goto error;
 374                         }
 375                         break;
 376                 case 'g':
 377                         lttng_set_tracing_group(optarg);
 378                         break;
 379                 case 'n':
 380                         opt_no_sessiond = 1;
 381                         break;
 382                 case OPT_SESSION_PATH:
 383                         free(opt_sessiond_path);
 384                         opt_sessiond_path = strdup(optarg);
 385                         if (!opt_sessiond_path) {
 386                                 ret = -1;
 387                                 goto error;
 388                         }
 389                         break;
 390                 case OPT_RELAYD_PATH:
 391                         free(opt_relayd_path);
 392                         opt_relayd_path = strdup(optarg);
 393                         if (!opt_relayd_path) {
 394                                 ret = -1;
 395                                 goto error;
 396                         }
 397                         break;
 398                 case OPT_DUMP_OPTIONS:
 399                         list_options(stdout);
 400                         ret = 0;
 401                         goto end;
 402                 case OPT_DUMP_COMMANDS:
 403                         list_commands(commands, stdout);
 404                         ret = 0;
 405                         goto end;
 406                 default:
 407                         ret = 1;
 408                         goto error;
 409                 }
 410         }
 411
 412         /* If both options are specified, quiet wins */
 413         if (lttng_opt_verbose && lttng_opt_quiet) {
 414                 lttng_opt_verbose = 0;
 415         }
 416
 417         /* No leftovers, quit */
 418         if ((argc - optind) == 0) {
 419                 ret = 1;
 420                 goto error;
 421         }
 422
 423         /*
 424          * Handle leftovers which is a first level command with the trailing
 425          * options.
 426          */
 427         ret = handle_command(argc - optind, argv + optind);
 428         switch (ret) {
 429         case CMD_WARNING:
 430         case CMD_ERROR:
 431                 break;
 432         case CMD_UNDEFINED:
 433                 if (!command_exists(*(argv + optind))) {
 434                         MSG("lttng: %s is not an lttng command. See 'lttng --help'.",
 435                                         *(argv + optind));
 436                 } else {
 437                         ERR("Unrecognized argument used with \'%s\' command",
 438                                         *(argv + optind));
 439                 }
 440                 break;
 441         case CMD_FATAL:
 442         case CMD_UNSUPPORTED:
 443                 break;
 444         case -1:
 445                 ret = 1;
 446                 break;
 447         case 0:
 448                 break;
 449         default:
 450                 if (ret < 0) {
 451                         ret = -ret;
 452                 }
 453                 break;
 454         }
 455
 456 end:
 457 error:
 458         return ret;
 459 }
 460
 461
 462 /*
 463  *  main
 464  */
 465 int main(int argc, char *argv[])
 466 {
 467         int ret;
 468
 469         progname = argv[0] ? argv[0] : "lttng";
 470
 471         ret = set_signal_handler();
 472         if (ret < 0) {
 473                 clean_exit(ret);
 474         }
 475
 476         ret = parse_args(argc, argv);
 477         if (ret != 0) {
 478                 clean_exit(ret);
 479         }
 480
 481         return 0;
 482 }