src/bin/lttng/lttng.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 _LGPL_SOURCE
  19 #include <getopt.h>
  20 #include <signal.h>
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <string.h>
  24 #include <sys/types.h>
  25 #include <sys/wait.h>
  26 #include <unistd.h>
  27 #include <ctype.h>
  28
  29 #include <lttng/lttng.h>
  30 #include <common/error.h>
  31 #include <common/compat/getenv.h>
  32 #include <common/utils.h>
  33
  34 #include "command.h"
  35
  36 static const char *help_msg =
  37 #ifdef LTTNG_EMBED_HELP
  38 #include <lttng.1.h>
  39 #else
  40 NULL
  41 #endif
  42 ;
  43
  44 /* Variables */
  45 static char *progname;
  46 int opt_no_sessiond;
  47 char *opt_sessiond_path;
  48
  49 char *opt_relayd_path;
  50
  51 enum {
  52         OPT_RELAYD_PATH,
  53         OPT_SESSION_PATH,
  54         OPT_DUMP_OPTIONS,
  55         OPT_DUMP_COMMANDS,
  56 };
  57
  58 /* Getopt options. No first level command. */
  59 static struct option long_options[] = {
  60         {"version",          0, NULL, 'V'},
  61         {"help",             0, NULL, 'h'},
  62         {"group",            1, NULL, 'g'},
  63         {"verbose",          0, NULL, 'v'},
  64         {"quiet",            0, NULL, 'q'},
  65         {"mi",               1, NULL, 'm'},
  66         {"no-sessiond",      0, NULL, 'n'},
  67         {"sessiond-path",    1, NULL, OPT_SESSION_PATH},
  68         {"relayd-path",      1, NULL, OPT_RELAYD_PATH},
  69         {"list-options",     0, NULL, OPT_DUMP_OPTIONS},
  70         {"list-commands",    0, NULL, OPT_DUMP_COMMANDS},
  71         {NULL, 0, NULL, 0}
  72 };
  73
  74 /* First level command */
  75 static struct cmd_struct commands[] =  {
  76         { "add-context", cmd_add_context},
  77         { "create", cmd_create},
  78         { "destroy", cmd_destroy},
  79         { "disable-channel", cmd_disable_channels},
  80         { "disable-event", cmd_disable_events},
  81         { "enable-channel", cmd_enable_channels},
  82         { "enable-event", cmd_enable_events},
  83         { "help", NULL},
  84         { "list", cmd_list},
  85         { "load", cmd_load},
  86         { "metadata", cmd_metadata},
  87         { "regenerate", cmd_regenerate},
  88         { "rotate", cmd_rotate},
  89         { "enable-rotation", cmd_enable_rotation},
  90         { "disable-rotation", cmd_disable_rotation},
  91         { "save", cmd_save},
  92         { "set-session", cmd_set_session},
  93         { "snapshot", cmd_snapshot},
  94         { "start", cmd_start},
  95         { "status", cmd_status},
  96         { "stop", cmd_stop},
  97         { "track", cmd_track},
  98         { "untrack", cmd_untrack},
  99         { "version", cmd_version},
 100         { "view", cmd_view},
 101         { NULL, NULL}   /* Array closure */
 102 };
 103
 104 static void version(FILE *ofp)
 105 {
 106         fprintf(ofp, "%s (LTTng Trace Control) " VERSION" - " VERSION_NAME "%s\n",
 107                         progname,
 108                         GIT_VERSION[0] == '\0' ? "" : " - " GIT_VERSION);
 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 void show_basic_help(void)
 256 {
 257         puts("Usage: lttng [--group=GROUP] [--mi=TYPE] [--no-sessiond | --sessiond-path=PATH]");
 258         puts("             [--quiet | -v | -vv | -vvv] COMMAND [COMMAND OPTIONS]");
 259         puts("");
 260         puts("Available commands:");
 261         puts("");
 262         puts("Tracing sessions:");
 263         puts("  create            " CONFIG_CMD_DESCR_CREATE);
 264         puts("  destroy           " CONFIG_CMD_DESCR_DESTROY);
 265         puts("  load              " CONFIG_CMD_DESCR_LOAD);
 266         puts("  regenerate        " CONFIG_CMD_DESCR_REGENERATE);
 267         puts("  save              " CONFIG_CMD_DESCR_SAVE);
 268         puts("  set-session       " CONFIG_CMD_DESCR_SET_SESSION);
 269         puts("");
 270         puts("Channels:");
 271         puts("  add-context       " CONFIG_CMD_DESCR_ADD_CONTEXT);
 272         puts("  disable-channel   " CONFIG_CMD_DESCR_DISABLE_CHANNEL);
 273         puts("  enable-channel    " CONFIG_CMD_DESCR_ENABLE_CHANNEL);
 274         puts("");
 275         puts("Event rules:");
 276         puts("  disable-event     " CONFIG_CMD_DESCR_DISABLE_EVENT);
 277         puts("  enable-event      " CONFIG_CMD_DESCR_ENABLE_EVENT);
 278         puts("");
 279         puts("Status:");
 280         puts("  list              " CONFIG_CMD_DESCR_LIST);
 281         puts("  status            " CONFIG_CMD_DESCR_STATUS);
 282         puts("");
 283         puts("Control:");
 284         puts("  snapshot          " CONFIG_CMD_DESCR_SNAPSHOT);
 285         puts("  start             " CONFIG_CMD_DESCR_START);
 286         puts("  stop              " CONFIG_CMD_DESCR_STOP);
 287         puts("");
 288         puts("Resource tracking:");
 289         puts("  track             " CONFIG_CMD_DESCR_TRACK);
 290         puts("  untrack           " CONFIG_CMD_DESCR_UNTRACK);
 291         puts("");
 292         puts("Miscellaneous:");
 293         puts("  help              " CONFIG_CMD_DESCR_HELP);
 294         puts("  version           " CONFIG_CMD_DESCR_VERSION);
 295         puts("  view              " CONFIG_CMD_DESCR_VIEW);
 296         puts("");
 297         puts("Run `lttng help COMMAND` or `lttng COMMAND --help` to get help with");
 298         puts("command COMMAND.");
 299         puts("");
 300         puts("See `man lttng` for more help with the lttng command.");
 301 }
 302
 303 /*
 304  * Parse command line arguments.
 305  *
 306  * Return 0 if OK, else -1
 307  */
 308 static int parse_args(int argc, char **argv)
 309 {
 310         int opt, ret;
 311
 312         if (lttng_is_setuid_setgid()) {
 313                 ERR("'%s' is not allowed to be executed as a setuid/setgid binary for security reasons. Aborting.", argv[0]);
 314                 clean_exit(EXIT_FAILURE);
 315         }
 316
 317         if (argc < 2) {
 318                 show_basic_help();
 319                 clean_exit(EXIT_FAILURE);
 320         }
 321
 322         while ((opt = getopt_long(argc, argv, "+Vhnvqg:m:", long_options, NULL)) != -1) {
 323                 switch (opt) {
 324                 case 'V':
 325                         version(stdout);
 326                         ret = 0;
 327                         goto end;
 328                 case 'h':
 329                         ret = utils_show_help(1, "lttng", help_msg);
 330                         if (ret) {
 331                                 ERR("Cannot show --help for `lttng`");
 332                                 perror("exec");
 333                         }
 334                         goto end;
 335                 case 'v':
 336                         /* There is only 3 possible level of verbosity. (-vvv) */
 337                         if (lttng_opt_verbose < 3) {
 338                                 lttng_opt_verbose += 1;
 339                         }
 340                         break;
 341                 case 'q':
 342                         lttng_opt_quiet = 1;
 343                         break;
 344                 case 'm':
 345                         lttng_opt_mi = mi_output_type(optarg);
 346                         if (lttng_opt_mi < 0) {
 347                                 ret = lttng_opt_mi;
 348                                 goto error;
 349                         }
 350                         break;
 351                 case 'g':
 352                         lttng_set_tracing_group(optarg);
 353                         break;
 354                 case 'n':
 355                         opt_no_sessiond = 1;
 356                         break;
 357                 case OPT_SESSION_PATH:
 358                         free(opt_sessiond_path);
 359                         opt_sessiond_path = strdup(optarg);
 360                         if (!opt_sessiond_path) {
 361                                 ret = -1;
 362                                 goto error;
 363                         }
 364                         break;
 365                 case OPT_RELAYD_PATH:
 366                         free(opt_relayd_path);
 367                         opt_relayd_path = strdup(optarg);
 368                         if (!opt_relayd_path) {
 369                                 ret = -1;
 370                                 goto error;
 371                         }
 372                         break;
 373                 case OPT_DUMP_OPTIONS:
 374                         list_options(stdout);
 375                         ret = 0;
 376                         goto end;
 377                 case OPT_DUMP_COMMANDS:
 378                         list_commands(commands, stdout);
 379                         ret = 0;
 380                         goto end;
 381                 default:
 382                         ret = 1;
 383                         goto error;
 384                 }
 385         }
 386
 387         /* If both options are specified, quiet wins */
 388         if (lttng_opt_verbose && lttng_opt_quiet) {
 389                 lttng_opt_verbose = 0;
 390         }
 391
 392         /* No leftovers, quit */
 393         if ((argc - optind) == 0) {
 394                 ret = 1;
 395                 goto error;
 396         }
 397
 398         /*
 399          * Handle leftovers which is a first level command with the trailing
 400          * options.
 401          */
 402         ret = handle_command(argc - optind, argv + optind);
 403         switch (ret) {
 404         case CMD_WARNING:
 405                 WARN("Some command(s) went wrong");
 406                 break;
 407         case CMD_ERROR:
 408                 ERR("Command error");
 409                 break;
 410         case CMD_UNDEFINED:
 411                 ERR("Undefined command or invalid arguments");
 412                 break;
 413         case CMD_FATAL:
 414                 ERR("Fatal error");
 415                 break;
 416         case CMD_UNSUPPORTED:
 417                 ERR("Unsupported command");
 418                 break;
 419         case -1:
 420                 ret = 1;
 421                 break;
 422         case 0:
 423                 break;
 424         default:
 425                 if (ret < 0) {
 426                         ret = -ret;
 427                 }
 428                 break;
 429         }
 430
 431 end:
 432 error:
 433         return ret;
 434 }
 435
 436
 437 /*
 438  *  main
 439  */
 440 int main(int argc, char *argv[])
 441 {
 442         int ret;
 443
 444         progname = argv[0] ? argv[0] : "lttng";
 445
 446         ret = set_signal_handler();
 447         if (ret < 0) {
 448                 clean_exit(ret);
 449         }
 450
 451         ret = parse_args(argc, argv);
 452         if (ret != 0) {
 453                 clean_exit(ret);
 454         }
 455
 456         return 0;
 457 }