src/bin/lttng/lttng.c

   1 /*
   2  * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
   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.h>
  21 #include <common/compat/getenv.h>
  22 #include <common/utils.h>
  23
  24 #include "command.h"
  25 #include "version.h"
  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         { "add-map", cmd_add_map},
  77         { "enable-map", cmd_enable_map},
  78         { "disable-map", cmd_disable_map},
  79         { "help", NULL},
  80         { "list", cmd_list},
  81         { "list-triggers", cmd_list_triggers},
  82         { "load", cmd_load},
  83         { "metadata", cmd_metadata},
  84         { "regenerate", cmd_regenerate},
  85         { "remove-trigger", cmd_remove_trigger},
  86         { "rotate", cmd_rotate},
  87         { "enable-rotation", cmd_enable_rotation},
  88         { "disable-rotation", cmd_disable_rotation},
  89         { "save", cmd_save},
  90         { "set-session", cmd_set_session},
  91         { "snapshot", cmd_snapshot},
  92         { "start", cmd_start},
  93         { "status", cmd_status},
  94         { "stop", cmd_stop},
  95         { "track", cmd_track},
  96         { "untrack", cmd_untrack},
  97         { "version", cmd_version},
  98         { "view", cmd_view},
  99         { "view-map", cmd_view_map},
 100         { NULL, NULL}   /* Array closure */
 101 };
 102
 103 static void version(FILE *ofp)
 104 {
 105         fprintf(ofp, "%s (LTTng Trace Control) " VERSION" - " VERSION_NAME "%s%s\n",
 106                         progname,
 107                         GIT_VERSION[0] == '\0' ? "" : " - " GIT_VERSION,
 108                         EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " EXTRA_VERSION_NAME);
 109 }
 110
 111 /*
 112  * Find the MI output type enum from a string. This function is for the support
 113  * of machine interface output.
 114  */
 115 static int mi_output_type(const char *output_type)
 116 {
 117         int ret = 0;
 118
 119         if (!strncasecmp("xml", output_type, 3)) {
 120                 ret = LTTNG_MI_XML;
 121         } else {
 122                 /* Invalid output format */
 123                 ERR("MI output format not supported");
 124                 ret = -LTTNG_ERR_MI_OUTPUT_TYPE;
 125         }
 126
 127         return ret;
 128 }
 129
 130 /*
 131  *  list_options
 132  *
 133  *  List options line by line. This is mostly for bash auto completion and to
 134  *  avoid difficult parsing.
 135  */
 136 static void list_options(FILE *ofp)
 137 {
 138         int i = 0;
 139         struct option *option = NULL;
 140
 141         option = &long_options[i];
 142         while (option->name != NULL) {
 143                 fprintf(ofp, "--%s\n", option->name);
 144
 145                 if (isprint(option->val)) {
 146                         fprintf(ofp, "-%c\n", option->val);
 147                 }
 148
 149                 i++;
 150                 option = &long_options[i];
 151         }
 152 }
 153
 154 /*
 155  * clean_exit
 156  */
 157 static void clean_exit(int code)
 158 {
 159         DBG("Clean exit");
 160         exit(code);
 161 }
 162
 163 /*
 164  *  sighandler
 165  *
 166  *  Signal handler for the daemon
 167  */
 168 static void sighandler(int sig)
 169 {
 170         switch (sig) {
 171                 case SIGTERM:
 172                         DBG("SIGTERM caught");
 173                         clean_exit(EXIT_FAILURE);
 174                         break;
 175                 default:
 176                         DBG("Unknown signal %d caught", sig);
 177                         break;
 178         }
 179
 180         return;
 181 }
 182
 183 /*
 184  *  set_signal_handler
 185  *
 186  *  Setup signal handler for SIGCHLD and SIGTERM.
 187  */
 188 static int set_signal_handler(void)
 189 {
 190         int ret = 0;
 191         struct sigaction sa;
 192         sigset_t sigset;
 193
 194         if ((ret = sigemptyset(&sigset)) < 0) {
 195                 PERROR("sigemptyset");
 196                 goto end;
 197         }
 198
 199         sa.sa_handler = sighandler;
 200         sa.sa_mask = sigset;
 201         sa.sa_flags = 0;
 202
 203         if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
 204                 PERROR("sigaction");
 205                 goto end;
 206         }
 207
 208 end:
 209         return ret;
 210 }
 211
 212 /*
 213  *  handle_command
 214  *
 215  *  Handle the full argv list of a first level command. Will find the command
 216  *  in the global commands array and call the function callback associated.
 217  *
 218  *  If command not found, return -1
 219  *  else, return function command error code.
 220  */
 221 static int handle_command(int argc, char **argv)
 222 {
 223         int i = 0, ret;
 224         struct cmd_struct *cmd;
 225
 226         if (*argv == NULL) {
 227                 ret = CMD_SUCCESS;
 228                 goto end;
 229         }
 230
 231         /* Special case for help command which needs the commands array */
 232         if (strcmp(argv[0], "help") == 0) {
 233                 ret = cmd_help(argc, (const char**) argv, commands);
 234                 goto end;
 235         }
 236
 237         cmd = &commands[i];
 238         while (cmd->name != NULL) {
 239                 /* Find command */
 240                 if (strcmp(argv[0], cmd->name) == 0) {
 241                         ret = cmd->func(argc, (const char**) argv);
 242                         goto end;
 243                 }
 244                 i++;
 245                 cmd = &commands[i];
 246         }
 247
 248         /* Command not found */
 249         ret = CMD_UNDEFINED;
 250
 251 end:
 252         return ret;
 253 }
 254
 255 static bool command_exists(const char *command)
 256 {
 257         const struct cmd_struct *cmd = commands;
 258         bool exists = false;
 259
 260         while (cmd->name != NULL) {
 261                 if (!strcmp(command, cmd->name)) {
 262                         exists = true;
 263                         goto end;
 264                 }
 265                 cmd++;
 266         }
 267
 268 end:
 269         return exists;
 270 }
 271
 272 static void show_basic_help(void)
 273 {
 274         puts("Usage: lttng [--group=GROUP] [--mi=TYPE] [--no-sessiond | --sessiond-path=PATH]");
 275         puts("             [--quiet | -v | -vv | -vvv] COMMAND [COMMAND OPTIONS]");
 276         puts("");
 277         puts("Available commands:");
 278         puts("");
 279         puts("Tracing sessions:");
 280         puts("  create            " CONFIG_CMD_DESCR_CREATE);
 281         puts("  clear             " CONFIG_CMD_DESCR_CLEAR);
 282         puts("  destroy           " CONFIG_CMD_DESCR_DESTROY);
 283         puts("  load              " CONFIG_CMD_DESCR_LOAD);
 284         puts("  regenerate        " CONFIG_CMD_DESCR_REGENERATE);
 285         puts("  save              " CONFIG_CMD_DESCR_SAVE);
 286         puts("  set-session       " CONFIG_CMD_DESCR_SET_SESSION);
 287         puts("");
 288         puts("Channels:");
 289         puts("  add-context       " CONFIG_CMD_DESCR_ADD_CONTEXT);
 290         puts("  disable-channel   " CONFIG_CMD_DESCR_DISABLE_CHANNEL);
 291         puts("  enable-channel    " CONFIG_CMD_DESCR_ENABLE_CHANNEL);
 292         puts("");
 293         puts("Maps:");
 294         puts("  add-map           " CONFIG_CMD_DESCR_ADD_MAP);
 295         puts("  remove-map        " CONFIG_CMD_DESCR_ADD_MAP);
 296         puts("");
 297         puts("Event rules:");
 298         puts("  disable-event     " CONFIG_CMD_DESCR_DISABLE_EVENT);
 299         puts("  enable-event      " CONFIG_CMD_DESCR_ENABLE_EVENT);
 300         puts("");
 301         puts("Status:");
 302         puts("  list              " CONFIG_CMD_DESCR_LIST);
 303         puts("  status            " CONFIG_CMD_DESCR_STATUS);
 304         puts("");
 305         puts("Control:");
 306         puts("  snapshot          " CONFIG_CMD_DESCR_SNAPSHOT);
 307         puts("  start             " CONFIG_CMD_DESCR_START);
 308         puts("  stop              " CONFIG_CMD_DESCR_STOP);
 309         puts("");
 310         puts("Tracing session rotation:");
 311         puts("  disable-rotation  " CONFIG_CMD_DESCR_DISABLE_ROTATION);
 312         puts("  enable-rotation   " CONFIG_CMD_DESCR_ENABLE_ROTATION);
 313         puts("  rotate            " CONFIG_CMD_DESCR_ROTATE);
 314         puts("");
 315         puts("Resource tracking:");
 316         puts("  track             " CONFIG_CMD_DESCR_TRACK);
 317         puts("  untrack           " CONFIG_CMD_DESCR_UNTRACK);
 318         puts("");
 319         puts("Miscellaneous:");
 320         puts("  help              " CONFIG_CMD_DESCR_HELP);
 321         puts("  version           " CONFIG_CMD_DESCR_VERSION);
 322         puts("  view              " CONFIG_CMD_DESCR_VIEW);
 323         puts("");
 324         puts("Run `lttng help COMMAND` or `lttng COMMAND --help` to get help with");
 325         puts("command COMMAND.");
 326         puts("");
 327         puts("See `man lttng` for more help with the lttng command.");
 328 }
 329
 330 /*
 331  * Parse command line arguments.
 332  *
 333  * Return 0 if OK, else -1
 334  */
 335 static int parse_args(int argc, char **argv)
 336 {
 337         int opt, ret;
 338
 339         if (lttng_is_setuid_setgid()) {
 340                 ERR("'%s' is not allowed to be executed as a setuid/setgid binary for security reasons. Aborting.", argv[0]);
 341                 clean_exit(EXIT_FAILURE);
 342         }
 343
 344         if (argc < 2) {
 345                 show_basic_help();
 346                 clean_exit(EXIT_FAILURE);
 347         }
 348
 349         while ((opt = getopt_long(argc, argv, "+Vhnvqg:m:", long_options, NULL)) != -1) {
 350                 switch (opt) {
 351                 case 'V':
 352                         version(stdout);
 353                         ret = 0;
 354                         goto end;
 355                 case 'h':
 356                         ret = utils_show_help(1, "lttng", help_msg);
 357                         if (ret) {
 358                                 ERR("Cannot show --help for `lttng`");
 359                                 perror("exec");
 360                         }
 361                         goto end;
 362                 case 'v':
 363                         /* There is only 3 possible level of verbosity. (-vvv) */
 364                         if (lttng_opt_verbose < 3) {
 365                                 lttng_opt_verbose += 1;
 366                         }
 367                         break;
 368                 case 'q':
 369                         lttng_opt_quiet = 1;
 370                         break;
 371                 case 'm':
 372                         lttng_opt_mi = mi_output_type(optarg);
 373                         if (lttng_opt_mi < 0) {
 374                                 ret = lttng_opt_mi;
 375                                 goto error;
 376                         }
 377                         break;
 378                 case 'g':
 379                         lttng_set_tracing_group(optarg);
 380                         break;
 381                 case 'n':
 382                         opt_no_sessiond = 1;
 383                         break;
 384                 case OPT_SESSION_PATH:
 385                         free(opt_sessiond_path);
 386                         opt_sessiond_path = strdup(optarg);
 387                         if (!opt_sessiond_path) {
 388                                 ret = -1;
 389                                 goto error;
 390                         }
 391                         break;
 392                 case OPT_RELAYD_PATH:
 393                         free(opt_relayd_path);
 394                         opt_relayd_path = strdup(optarg);
 395                         if (!opt_relayd_path) {
 396                                 ret = -1;
 397                                 goto error;
 398                         }
 399                         break;
 400                 case OPT_DUMP_OPTIONS:
 401                         list_options(stdout);
 402                         ret = 0;
 403                         goto end;
 404                 case OPT_DUMP_COMMANDS:
 405                         list_commands(commands, stdout);
 406                         ret = 0;
 407                         goto end;
 408                 default:
 409                         ret = 1;
 410                         goto error;
 411                 }
 412         }
 413
 414         /* If both options are specified, quiet wins */
 415         if (lttng_opt_verbose && lttng_opt_quiet) {
 416                 lttng_opt_verbose = 0;
 417         }
 418
 419         /* No leftovers, quit */
 420         if ((argc - optind) == 0) {
 421                 ret = 1;
 422                 goto error;
 423         }
 424
 425         /*
 426          * Handle leftovers which is a first level command with the trailing
 427          * options.
 428          */
 429         ret = handle_command(argc - optind, argv + optind);
 430         switch (ret) {
 431         case CMD_WARNING:
 432         case CMD_ERROR:
 433                 break;
 434         case CMD_UNDEFINED:
 435                 if (!command_exists(*(argv + optind))) {
 436                         MSG("lttng: %s is not an lttng command. See 'lttng --help'.",
 437                                         *(argv + optind));
 438                 } else {
 439                         ERR("Unrecognized argument used with \'%s\' command",
 440                                         *(argv + optind));
 441                 }
 442                 break;
 443         case CMD_FATAL:
 444         case CMD_UNSUPPORTED:
 445                 break;
 446         case -1:
 447                 ret = 1;
 448                 break;
 449         case 0:
 450                 break;
 451         default:
 452                 if (ret < 0) {
 453                         ret = -ret;
 454                 }
 455                 break;
 456         }
 457
 458 end:
 459 error:
 460         return ret;
 461 }
 462
 463
 464 /*
 465  *  main
 466  */
 467 int main(int argc, char *argv[])
 468 {
 469         int ret;
 470
 471         progname = argv[0] ? argv[0] : "lttng";
 472
 473         ret = set_signal_handler();
 474         if (ret < 0) {
 475                 clean_exit(ret);
 476         }
 477
 478         ret = parse_args(argc, argv);
 479         if (ret != 0) {
 480                 clean_exit(ret);
 481         }
 482
 483         return 0;
 484 }