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
  33 #include "command.h"
  34
  35 /* Variables */
  36 static 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         { "list", cmd_list},
  68         { "status", cmd_status},
  69         { "create", cmd_create},
  70         { "destroy", cmd_destroy},
  71         { "start", cmd_start},
  72         { "stop", cmd_stop},
  73         { "enable-event", cmd_enable_events},
  74         { "disable-event", cmd_disable_events},
  75         { "enable-channel", cmd_enable_channels},
  76         { "disable-channel", cmd_disable_channels},
  77         { "add-context", cmd_add_context},
  78         { "set-session", cmd_set_session},
  79         { "version", cmd_version},
  80         { "calibrate", cmd_calibrate},
  81         { "view", cmd_view},
  82         { "snapshot", cmd_snapshot},
  83         { "save", cmd_save},
  84         { "load", cmd_load},
  85         { "track", cmd_track},
  86         { "untrack", cmd_untrack},
  87         { "metadata", cmd_metadata},
  88         { NULL, NULL}   /* Array closure */
  89 };
  90
  91 static void usage(FILE *ofp)
  92 {
  93         fprintf(ofp, "LTTng Trace Control " VERSION " - " VERSION_NAME "%s\n\n",
  94                 GIT_VERSION[0] == '\0' ? "" : " - " GIT_VERSION);
  95         fprintf(ofp, "usage: lttng [OPTIONS] <COMMAND> [<ARGS>]\n");
  96         fprintf(ofp, "\n");
  97         fprintf(ofp, "Options:\n");
  98         fprintf(ofp, "  -V, --version              Show version\n");
  99         fprintf(ofp, "  -h, --help                 Show this help\n");
 100         fprintf(ofp, "      --list-options         Simple listing of lttng options\n");
 101         fprintf(ofp, "      --list-commands        Simple listing of lttng commands\n");
 102         fprintf(ofp, "  -v, --verbose              Increase verbosity\n");
 103         fprintf(ofp, "  -q, --quiet                Quiet mode\n");
 104         fprintf(ofp, "  -m, --mi TYPE              Machine Interface mode.\n");
 105         fprintf(ofp, "                                 Type: xml\n");
 106         fprintf(ofp, "  -g, --group NAME           Unix tracing group name. (default: tracing)\n");
 107         fprintf(ofp, "  -n, --no-sessiond          Don't spawn a session daemon\n");
 108         fprintf(ofp, "      --sessiond-path PATH   Session daemon full path\n");
 109         fprintf(ofp, "      --relayd-path PATH     Relayd daemon full path\n");
 110         fprintf(ofp, "\n");
 111         fprintf(ofp, "Commands:\n");
 112         fprintf(ofp, "    add-context       Add context to event and/or channel\n");
 113         fprintf(ofp, "    calibrate         Quantify LTTng overhead\n");
 114         fprintf(ofp, "    create            Create tracing session\n");
 115         fprintf(ofp, "    destroy           Tear down tracing session\n");
 116         fprintf(ofp, "    enable-channel    Enable tracing channel\n");
 117         fprintf(ofp, "    enable-event      Enable tracing event\n");
 118         fprintf(ofp, "    disable-channel   Disable tracing channel\n");
 119         fprintf(ofp, "    disable-event     Disable tracing event\n");
 120         fprintf(ofp, "    list              List possible tracing options\n");
 121         fprintf(ofp, "    set-session       Set current session name\n");
 122         fprintf(ofp, "    snapshot          Snapshot buffers of current session name\n");
 123         fprintf(ofp, "    start             Start tracing\n");
 124         fprintf(ofp, "    status            Show current session's details\n");
 125         fprintf(ofp, "    stop              Stop tracing\n");
 126         fprintf(ofp, "    version           Show version information\n");
 127         fprintf(ofp, "    view              Start trace viewer\n");
 128         fprintf(ofp, "    save              Save session configuration\n");
 129         fprintf(ofp, "    load              Load session configuration\n");
 130         fprintf(ofp, "    track             Track specific system resources\n");
 131         fprintf(ofp, "    untrack           Untrack specific system resources\n");
 132         fprintf(ofp, "    metadata          Regenerate the metadata of a session\n");
 133         fprintf(ofp, "\n");
 134         fprintf(ofp, "Each command also has its own -h, --help option.\n");
 135         fprintf(ofp, "\n");
 136         fprintf(ofp, "Please see the lttng(1) man page for full documentation.\n");
 137         fprintf(ofp, "See http://lttng.org for updates, bug reports and news.\n");
 138 }
 139
 140 static void version(FILE *ofp)
 141 {
 142         fprintf(ofp, "%s (LTTng Trace Control) " VERSION" - " VERSION_NAME "%s\n",
 143                         progname,
 144                         GIT_VERSION[0] == '\0' ? "" : " - " GIT_VERSION);
 145 }
 146
 147 /*
 148  * Find the MI output type enum from a string. This function is for the support
 149  * of machine interface output.
 150  */
 151 static int mi_output_type(const char *output_type)
 152 {
 153         int ret = 0;
 154
 155         if (!strncasecmp("xml", output_type, 3)) {
 156                 ret = LTTNG_MI_XML;
 157         } else {
 158                 /* Invalid output format */
 159                 ERR("MI output format not supported");
 160                 ret = -LTTNG_ERR_MI_OUTPUT_TYPE;
 161         }
 162
 163         return ret;
 164 }
 165
 166 /*
 167  *  list_options
 168  *
 169  *  List options line by line. This is mostly for bash auto completion and to
 170  *  avoid difficult parsing.
 171  */
 172 static void list_options(FILE *ofp)
 173 {
 174         int i = 0;
 175         struct option *option = NULL;
 176
 177         option = &long_options[i];
 178         while (option->name != NULL) {
 179                 fprintf(ofp, "--%s\n", option->name);
 180
 181                 if (isprint(option->val)) {
 182                         fprintf(ofp, "-%c\n", option->val);
 183                 }
 184
 185                 i++;
 186                 option = &long_options[i];
 187         }
 188 }
 189
 190 /*
 191  * clean_exit
 192  */
 193 static void clean_exit(int code)
 194 {
 195         DBG("Clean exit");
 196         exit(code);
 197 }
 198
 199 /*
 200  *  sighandler
 201  *
 202  *  Signal handler for the daemon
 203  */
 204 static void sighandler(int sig)
 205 {
 206         switch (sig) {
 207                 case SIGTERM:
 208                         DBG("SIGTERM caught");
 209                         clean_exit(EXIT_FAILURE);
 210                         break;
 211                 default:
 212                         DBG("Unknown signal %d caught", sig);
 213                         break;
 214         }
 215
 216         return;
 217 }
 218
 219 /*
 220  *  set_signal_handler
 221  *
 222  *  Setup signal handler for SIGCHLD and SIGTERM.
 223  */
 224 static int set_signal_handler(void)
 225 {
 226         int ret = 0;
 227         struct sigaction sa;
 228         sigset_t sigset;
 229
 230         if ((ret = sigemptyset(&sigset)) < 0) {
 231                 PERROR("sigemptyset");
 232                 goto end;
 233         }
 234
 235         sa.sa_handler = sighandler;
 236         sa.sa_mask = sigset;
 237         sa.sa_flags = 0;
 238
 239         if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
 240                 PERROR("sigaction");
 241                 goto end;
 242         }
 243
 244 end:
 245         return ret;
 246 }
 247
 248 /*
 249  *  handle_command
 250  *
 251  *  Handle the full argv list of a first level command. Will find the command
 252  *  in the global commands array and call the function callback associated.
 253  *
 254  *  If command not found, return -1
 255  *  else, return function command error code.
 256  */
 257 static int handle_command(int argc, char **argv)
 258 {
 259         int i = 0, ret;
 260         struct cmd_struct *cmd;
 261
 262         if (*argv == NULL) {
 263                 ret = CMD_SUCCESS;
 264                 goto end;
 265         }
 266
 267         cmd = &commands[i];
 268         while (cmd->func != NULL) {
 269                 /* Find command */
 270                 if (strcmp(argv[0], cmd->name) == 0) {
 271                         ret = cmd->func(argc, (const char**) argv);
 272                         goto end;
 273                 }
 274                 i++;
 275                 cmd = &commands[i];
 276         }
 277
 278         /* Command not found */
 279         ret = CMD_UNDEFINED;
 280
 281 end:
 282         return ret;
 283 }
 284
 285 /*
 286  * Parse command line arguments.
 287  *
 288  * Return 0 if OK, else -1
 289  */
 290 static int parse_args(int argc, char **argv)
 291 {
 292         int opt, ret;
 293         char *user;
 294
 295         if (lttng_is_setuid_setgid()) {
 296                 ERR("'%s' is not allowed to be executed as a setuid/setgid binary for security reasons. Aborting.", argv[0]);
 297                 clean_exit(EXIT_FAILURE);
 298         }
 299
 300         if (argc < 2) {
 301                 usage(stderr);
 302                 clean_exit(EXIT_FAILURE);
 303         }
 304
 305         while ((opt = getopt_long(argc, argv, "+Vhnvqg:m:", long_options, NULL)) != -1) {
 306                 switch (opt) {
 307                 case 'V':
 308                         version(stdout);
 309                         ret = 0;
 310                         goto end;
 311                 case 'h':
 312                         usage(stdout);
 313                         ret = 0;
 314                         goto end;
 315                 case 'v':
 316                         /* There is only 3 possible level of verbosity. (-vvv) */
 317                         if (lttng_opt_verbose < 3) {
 318                                 lttng_opt_verbose += 1;
 319                         }
 320                         break;
 321                 case 'q':
 322                         lttng_opt_quiet = 1;
 323                         break;
 324                 case 'm':
 325                         lttng_opt_mi = mi_output_type(optarg);
 326                         if (lttng_opt_mi < 0) {
 327                                 ret = lttng_opt_mi;
 328                                 goto error;
 329                         }
 330                         break;
 331                 case 'g':
 332                         lttng_set_tracing_group(optarg);
 333                         break;
 334                 case 'n':
 335                         opt_no_sessiond = 1;
 336                         break;
 337                 case OPT_SESSION_PATH:
 338                         opt_sessiond_path = strdup(optarg);
 339                         if (!opt_sessiond_path) {
 340                                 ret = -1;
 341                                 goto error;
 342                         }
 343                         break;
 344                 case OPT_RELAYD_PATH:
 345                         opt_relayd_path = strdup(optarg);
 346                         if (!opt_relayd_path) {
 347                                 ret = -1;
 348                                 goto error;
 349                         }
 350                         break;
 351                 case OPT_DUMP_OPTIONS:
 352                         list_options(stdout);
 353                         ret = 0;
 354                         goto end;
 355                 case OPT_DUMP_COMMANDS:
 356                         list_commands(commands, stdout);
 357                         ret = 0;
 358                         goto end;
 359                 default:
 360                         usage(stderr);
 361                         ret = 1;
 362                         goto error;
 363                 }
 364         }
 365
 366         /* If both options are specified, quiet wins */
 367         if (lttng_opt_verbose && lttng_opt_quiet) {
 368                 lttng_opt_verbose = 0;
 369         }
 370
 371         /* No leftovers, print usage and quit */
 372         if ((argc - optind) == 0) {
 373                 usage(stderr);
 374                 ret = 1;
 375                 goto error;
 376         }
 377
 378         /* For Mathieu Desnoyers a.k.a. Dr. Tracing */
 379         user = getenv("USER");
 380         if (user != NULL && ((strncmp(progname, "drtrace", 7) == 0 ||
 381                                         strncmp("compudj", user, 7) == 0))) {
 382                 MSG("%c[%d;%dmWelcome back Dr Tracing!%c[%dm\n", 27,1,33,27,0);
 383         }
 384         /* Thanks Mathieu */
 385
 386         /*
 387          * Handle leftovers which is a first level command with the trailing
 388          * options.
 389          */
 390         ret = handle_command(argc - optind, argv + optind);
 391         switch (ret) {
 392         case CMD_WARNING:
 393                 WARN("Some command(s) went wrong");
 394                 break;
 395         case CMD_ERROR:
 396                 ERR("Command error");
 397                 break;
 398         case CMD_UNDEFINED:
 399                 ERR("Undefined command");
 400                 break;
 401         case CMD_FATAL:
 402                 ERR("Fatal error");
 403                 break;
 404         case CMD_UNSUPPORTED:
 405                 ERR("Unsupported command");
 406                 break;
 407         case -1:
 408                 usage(stderr);
 409                 ret = 1;
 410                 break;
 411         case 0:
 412                 break;
 413         default:
 414                 if (ret < 0) {
 415                         ret = -ret;
 416                 }
 417                 break;
 418         }
 419
 420 end:
 421 error:
 422         return ret;
 423 }
 424
 425
 426 /*
 427  *  main
 428  */
 429 int main(int argc, char *argv[])
 430 {
 431         int ret;
 432
 433         progname = argv[0] ? argv[0] : "lttng";
 434
 435         ret = set_signal_handler();
 436         if (ret < 0) {
 437                 clean_exit(ret);
 438         }
 439
 440         ret = parse_args(argc, argv);
 441         if (ret != 0) {
 442                 clean_exit(ret);
 443         }
 444
 445         return 0;
 446 }