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