src/bin/lttng-sessiond/main.c

   1 /*
   2  * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
   3  *                      Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   4  *               2013 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License, version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18  */
  19
  20 #define _LGPL_SOURCE
  21 #include <getopt.h>
  22 #include <grp.h>
  23 #include <limits.h>
  24 #include <paths.h>
  25 #include <pthread.h>
  26 #include <signal.h>
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30 #include <inttypes.h>
  31 #include <sys/mman.h>
  32 #include <sys/mount.h>
  33 #include <sys/resource.h>
  34 #include <sys/socket.h>
  35 #include <sys/stat.h>
  36 #include <sys/types.h>
  37 #include <sys/wait.h>
  38 #include <urcu/uatomic.h>
  39 #include <unistd.h>
  40 #include <ctype.h>
  41
  42 #include <common/common.h>
  43 #include <common/compat/socket.h>
  44 #include <common/compat/getenv.h>
  45 #include <common/defaults.h>
  46 #include <common/kernel-consumer/kernel-consumer.h>
  47 #include <common/futex.h>
  48 #include <common/relayd/relayd.h>
  49 #include <common/utils.h>
  50 #include <common/daemonize.h>
  51 #include <common/config/session-config.h>
  52 #include <common/dynamic-buffer.h>
  53 #include <lttng/event-internal.h>
  54
  55 #include "lttng-sessiond.h"
  56 #include "buffer-registry.h"
  57 #include "channel.h"
  58 #include "cmd.h"
  59 #include "consumer.h"
  60 #include "context.h"
  61 #include "event.h"
  62 #include "kernel.h"
  63 #include "kernel-consumer.h"
  64 #include "modprobe.h"
  65 #include "shm.h"
  66 #include "ust-ctl.h"
  67 #include "ust-consumer.h"
  68 #include "utils.h"
  69 #include "fd-limit.h"
  70 #include "health-sessiond.h"
  71 #include "testpoint.h"
  72 #include "notify-apps.h"
  73 #include "agent-thread.h"
  74 #include "save.h"
  75 #include "notification-thread.h"
  76 #include "notification-thread-commands.h"
  77 #include "rotation-thread.h"
  78 #include "lttng-syscall.h"
  79 #include "agent.h"
  80 #include "ht-cleanup.h"
  81 #include "sessiond-config.h"
  82 #include "timer.h"
  83 #include "thread.h"
  84 #include "client.h"
  85 #include "dispatch.h"
  86 #include "register.h"
  87 #include "manage-apps.h"
  88 #include "manage-kernel.h"
  89
  90 static const char *help_msg =
  91 #ifdef LTTNG_EMBED_HELP
  92 #include <lttng-sessiond.8.h>
  93 #else
  94 NULL
  95 #endif
  96 ;
  97
  98 const char *progname;
  99 static int lockfile_fd = -1;
 100
 101 /* Set to 1 when a SIGUSR1 signal is received. */
 102 static int recv_child_signal;
 103
 104 /* Command line options */
 105 static const struct option long_options[] = {
 106         { "client-sock", required_argument, 0, 'c' },
 107         { "apps-sock", required_argument, 0, 'a' },
 108         { "kconsumerd-cmd-sock", required_argument, 0, '\0' },
 109         { "kconsumerd-err-sock", required_argument, 0, '\0' },
 110         { "ustconsumerd32-cmd-sock", required_argument, 0, '\0' },
 111         { "ustconsumerd32-err-sock", required_argument, 0, '\0' },
 112         { "ustconsumerd64-cmd-sock", required_argument, 0, '\0' },
 113         { "ustconsumerd64-err-sock", required_argument, 0, '\0' },
 114         { "consumerd32-path", required_argument, 0, '\0' },
 115         { "consumerd32-libdir", required_argument, 0, '\0' },
 116         { "consumerd64-path", required_argument, 0, '\0' },
 117         { "consumerd64-libdir", required_argument, 0, '\0' },
 118         { "daemonize", no_argument, 0, 'd' },
 119         { "background", no_argument, 0, 'b' },
 120         { "sig-parent", no_argument, 0, 'S' },
 121         { "help", no_argument, 0, 'h' },
 122         { "group", required_argument, 0, 'g' },
 123         { "version", no_argument, 0, 'V' },
 124         { "quiet", no_argument, 0, 'q' },
 125         { "verbose", no_argument, 0, 'v' },
 126         { "verbose-consumer", no_argument, 0, '\0' },
 127         { "no-kernel", no_argument, 0, '\0' },
 128         { "pidfile", required_argument, 0, 'p' },
 129         { "agent-tcp-port", required_argument, 0, '\0' },
 130         { "config", required_argument, 0, 'f' },
 131         { "load", required_argument, 0, 'l' },
 132         { "kmod-probes", required_argument, 0, '\0' },
 133         { "extra-kmod-probes", required_argument, 0, '\0' },
 134         { NULL, 0, 0, 0 }
 135 };
 136
 137 /* Command line options to ignore from configuration file */
 138 static const char *config_ignore_options[] = { "help", "version", "config" };
 139
 140 /*
 141  * This pipe is used to inform the thread managing application communication
 142  * that a command is queued and ready to be processed.
 143  */
 144 static int apps_cmd_pipe[2] = { -1, -1 };
 145 static int apps_cmd_notify_pipe[2] = { -1, -1 };
 146
 147 /*
 148  * UST registration command queue. This queue is tied with a futex and uses a N
 149  * wakers / 1 waiter implemented and detailed in futex.c/.h
 150  *
 151  * The thread_registration_apps and thread_dispatch_ust_registration uses this
 152  * queue along with the wait/wake scheme. The thread_manage_apps receives down
 153  * the line new application socket and monitors it for any I/O error or clean
 154  * close that triggers an unregistration of the application.
 155  */
 156 static struct ust_cmd_queue ust_cmd_queue;
 157
 158 static const char *module_proc_lttng = "/proc/lttng";
 159
 160 /*
 161  * Section name to look for in the daemon configuration file.
 162  */
 163 static const char * const config_section_name = "sessiond";
 164
 165 /* Am I root or not. Set to 1 if the daemon is running as root */
 166 static int is_root;
 167
 168 /*
 169  * Stop all threads by closing the thread quit pipe.
 170  */
 171 static void stop_threads(void)
 172 {
 173         int ret;
 174
 175         /* Stopping all threads */
 176         DBG("Terminating all threads");
 177         ret = sessiond_notify_quit_pipe();
 178         if (ret < 0) {
 179                 ERR("write error on thread quit pipe");
 180         }
 181 }
 182
 183 /*
 184  * Close every consumer sockets.
 185  */
 186 static void close_consumer_sockets(void)
 187 {
 188         int ret;
 189
 190         if (kconsumer_data.err_sock >= 0) {
 191                 ret = close(kconsumer_data.err_sock);
 192                 if (ret < 0) {
 193                         PERROR("kernel consumer err_sock close");
 194                 }
 195         }
 196         if (ustconsumer32_data.err_sock >= 0) {
 197                 ret = close(ustconsumer32_data.err_sock);
 198                 if (ret < 0) {
 199                         PERROR("UST consumerd32 err_sock close");
 200                 }
 201         }
 202         if (ustconsumer64_data.err_sock >= 0) {
 203                 ret = close(ustconsumer64_data.err_sock);
 204                 if (ret < 0) {
 205                         PERROR("UST consumerd64 err_sock close");
 206                 }
 207         }
 208         if (kconsumer_data.cmd_sock >= 0) {
 209                 ret = close(kconsumer_data.cmd_sock);
 210                 if (ret < 0) {
 211                         PERROR("kernel consumer cmd_sock close");
 212                 }
 213         }
 214         if (ustconsumer32_data.cmd_sock >= 0) {
 215                 ret = close(ustconsumer32_data.cmd_sock);
 216                 if (ret < 0) {
 217                         PERROR("UST consumerd32 cmd_sock close");
 218                 }
 219         }
 220         if (ustconsumer64_data.cmd_sock >= 0) {
 221                 ret = close(ustconsumer64_data.cmd_sock);
 222                 if (ret < 0) {
 223                         PERROR("UST consumerd64 cmd_sock close");
 224                 }
 225         }
 226         if (kconsumer_data.channel_monitor_pipe >= 0) {
 227                 ret = close(kconsumer_data.channel_monitor_pipe);
 228                 if (ret < 0) {
 229                         PERROR("kernel consumer channel monitor pipe close");
 230                 }
 231         }
 232         if (ustconsumer32_data.channel_monitor_pipe >= 0) {
 233                 ret = close(ustconsumer32_data.channel_monitor_pipe);
 234                 if (ret < 0) {
 235                         PERROR("UST consumerd32 channel monitor pipe close");
 236                 }
 237         }
 238         if (ustconsumer64_data.channel_monitor_pipe >= 0) {
 239                 ret = close(ustconsumer64_data.channel_monitor_pipe);
 240                 if (ret < 0) {
 241                         PERROR("UST consumerd64 channel monitor pipe close");
 242                 }
 243         }
 244 }
 245
 246 /*
 247  * Wait on consumer process termination.
 248  *
 249  * Need to be called with the consumer data lock held or from a context
 250  * ensuring no concurrent access to data (e.g: cleanup).
 251  */
 252 static void wait_consumer(struct consumer_data *consumer_data)
 253 {
 254         pid_t ret;
 255         int status;
 256
 257         if (consumer_data->pid <= 0) {
 258                 return;
 259         }
 260
 261         DBG("Waiting for complete teardown of consumerd (PID: %d)",
 262                         consumer_data->pid);
 263         ret = waitpid(consumer_data->pid, &status, 0);
 264         if (ret == -1) {
 265                 PERROR("consumerd waitpid pid: %d", consumer_data->pid)
 266         } else  if (!WIFEXITED(status)) {
 267                 ERR("consumerd termination with error: %d",
 268                                 WEXITSTATUS(ret));
 269         }
 270         consumer_data->pid = 0;
 271 }
 272
 273 /*
 274  * Cleanup the session daemon's data structures.
 275  */
 276 static void sessiond_cleanup(void)
 277 {
 278         int ret;
 279         struct ltt_session_list *session_list = session_get_list();
 280
 281         DBG("Cleanup sessiond");
 282
 283         /*
 284          * Close the thread quit pipe. It has already done its job,
 285          * since we are now called.
 286          */
 287         sessiond_close_quit_pipe();
 288         utils_close_pipe(apps_cmd_pipe);
 289         utils_close_pipe(apps_cmd_notify_pipe);
 290         utils_close_pipe(kernel_poll_pipe);
 291
 292         ret = remove(config.pid_file_path.value);
 293         if (ret < 0) {
 294                 PERROR("remove pidfile %s", config.pid_file_path.value);
 295         }
 296
 297         DBG("Removing sessiond and consumerd content of directory %s",
 298                 config.rundir.value);
 299
 300         /* sessiond */
 301         DBG("Removing %s", config.pid_file_path.value);
 302         (void) unlink(config.pid_file_path.value);
 303
 304         DBG("Removing %s", config.agent_port_file_path.value);
 305         (void) unlink(config.agent_port_file_path.value);
 306
 307         /* kconsumerd */
 308         DBG("Removing %s", kconsumer_data.err_unix_sock_path);
 309         (void) unlink(kconsumer_data.err_unix_sock_path);
 310
 311         DBG("Removing directory %s", config.kconsumerd_path.value);
 312         (void) rmdir(config.kconsumerd_path.value);
 313
 314         /* ust consumerd 32 */
 315         DBG("Removing %s", config.consumerd32_err_unix_sock_path.value);
 316         (void) unlink(config.consumerd32_err_unix_sock_path.value);
 317
 318         DBG("Removing directory %s", config.consumerd32_path.value);
 319         (void) rmdir(config.consumerd32_path.value);
 320
 321         /* ust consumerd 64 */
 322         DBG("Removing %s", config.consumerd64_err_unix_sock_path.value);
 323         (void) unlink(config.consumerd64_err_unix_sock_path.value);
 324
 325         DBG("Removing directory %s", config.consumerd64_path.value);
 326         (void) rmdir(config.consumerd64_path.value);
 327
 328         pthread_mutex_destroy(&session_list->lock);
 329
 330         wait_consumer(&kconsumer_data);
 331         wait_consumer(&ustconsumer64_data);
 332         wait_consumer(&ustconsumer32_data);
 333
 334         DBG("Cleaning up all agent apps");
 335         agent_app_ht_clean();
 336
 337         DBG("Closing all UST sockets");
 338         ust_app_clean_list();
 339         buffer_reg_destroy_registries();
 340
 341         if (is_root && !config.no_kernel) {
 342                 DBG2("Closing kernel fd");
 343                 if (kernel_tracer_fd >= 0) {
 344                         ret = close(kernel_tracer_fd);
 345                         if (ret) {
 346                                 PERROR("close");
 347                         }
 348                 }
 349                 DBG("Unloading kernel modules");
 350                 modprobe_remove_lttng_all();
 351                 free(syscall_table);
 352         }
 353
 354         close_consumer_sockets();
 355
 356         /*
 357          * We do NOT rmdir rundir because there are other processes
 358          * using it, for instance lttng-relayd, which can start in
 359          * parallel with this teardown.
 360          */
 361 }
 362
 363 /*
 364  * Cleanup the daemon's option data structures.
 365  */
 366 static void sessiond_cleanup_options(void)
 367 {
 368         DBG("Cleaning up options");
 369
 370         sessiond_config_fini(&config);
 371
 372         run_as_destroy_worker();
 373 }
 374
 375 /*
 376  * Setup necessary data for kernel tracer action.
 377  */
 378 static int init_kernel_tracer(void)
 379 {
 380         int ret;
 381
 382         /* Modprobe lttng kernel modules */
 383         ret = modprobe_lttng_control();
 384         if (ret < 0) {
 385                 goto error;
 386         }
 387
 388         /* Open debugfs lttng */
 389         kernel_tracer_fd = open(module_proc_lttng, O_RDWR);
 390         if (kernel_tracer_fd < 0) {
 391                 DBG("Failed to open %s", module_proc_lttng);
 392                 goto error_open;
 393         }
 394
 395         /* Validate kernel version */
 396         ret = kernel_validate_version(kernel_tracer_fd, &kernel_tracer_version,
 397                         &kernel_tracer_abi_version);
 398         if (ret < 0) {
 399                 goto error_version;
 400         }
 401
 402         ret = modprobe_lttng_data();
 403         if (ret < 0) {
 404                 goto error_modules;
 405         }
 406
 407         ret = kernel_supports_ring_buffer_snapshot_sample_positions(
 408                         kernel_tracer_fd);
 409         if (ret < 0) {
 410                 goto error_modules;
 411         }
 412
 413         if (ret < 1) {
 414                 WARN("Kernel tracer does not support buffer monitoring. "
 415                         "The monitoring timer of channels in the kernel domain "
 416                         "will be set to 0 (disabled).");
 417         }
 418
 419         DBG("Kernel tracer fd %d", kernel_tracer_fd);
 420         return 0;
 421
 422 error_version:
 423         modprobe_remove_lttng_control();
 424         ret = close(kernel_tracer_fd);
 425         if (ret) {
 426                 PERROR("close");
 427         }
 428         kernel_tracer_fd = -1;
 429         return LTTNG_ERR_KERN_VERSION;
 430
 431 error_modules:
 432         ret = close(kernel_tracer_fd);
 433         if (ret) {
 434                 PERROR("close");
 435         }
 436
 437 error_open:
 438         modprobe_remove_lttng_control();
 439
 440 error:
 441         WARN("No kernel tracer available");
 442         kernel_tracer_fd = -1;
 443         if (!is_root) {
 444                 return LTTNG_ERR_NEED_ROOT_SESSIOND;
 445         } else {
 446                 return LTTNG_ERR_KERN_NA;
 447         }
 448 }
 449
 450 static int string_match(const char *str1, const char *str2)
 451 {
 452         return (str1 && str2) && !strcmp(str1, str2);
 453 }
 454
 455 /*
 456  * Take an option from the getopt output and set it in the right variable to be
 457  * used later.
 458  *
 459  * Return 0 on success else a negative value.
 460  */
 461 static int set_option(int opt, const char *arg, const char *optname)
 462 {
 463         int ret = 0;
 464
 465         if (string_match(optname, "client-sock") || opt == 'c') {
 466                 if (!arg || *arg == '\0') {
 467                         ret = -EINVAL;
 468                         goto end;
 469                 }
 470                 if (lttng_is_setuid_setgid()) {
 471                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 472                                 "-c, --client-sock");
 473                 } else {
 474                         config_string_set(&config.client_unix_sock_path,
 475                                         strdup(arg));
 476                         if (!config.client_unix_sock_path.value) {
 477                                 ret = -ENOMEM;
 478                                 PERROR("strdup");
 479                         }
 480                 }
 481         } else if (string_match(optname, "apps-sock") || opt == 'a') {
 482                 if (!arg || *arg == '\0') {
 483                         ret = -EINVAL;
 484                         goto end;
 485                 }
 486                 if (lttng_is_setuid_setgid()) {
 487                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 488                                 "-a, --apps-sock");
 489                 } else {
 490                         config_string_set(&config.apps_unix_sock_path,
 491                                         strdup(arg));
 492                         if (!config.apps_unix_sock_path.value) {
 493                                 ret = -ENOMEM;
 494                                 PERROR("strdup");
 495                         }
 496                 }
 497         } else if (string_match(optname, "daemonize") || opt == 'd') {
 498                 config.daemonize = true;
 499         } else if (string_match(optname, "background") || opt == 'b') {
 500                 config.background = true;
 501         } else if (string_match(optname, "group") || opt == 'g') {
 502                 if (!arg || *arg == '\0') {
 503                         ret = -EINVAL;
 504                         goto end;
 505                 }
 506                 if (lttng_is_setuid_setgid()) {
 507                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 508                                 "-g, --group");
 509                 } else {
 510                         config_string_set(&config.tracing_group_name,
 511                                         strdup(arg));
 512                         if (!config.tracing_group_name.value) {
 513                                 ret = -ENOMEM;
 514                                 PERROR("strdup");
 515                         }
 516                 }
 517         } else if (string_match(optname, "help") || opt == 'h') {
 518                 ret = utils_show_help(8, "lttng-sessiond", help_msg);
 519                 if (ret) {
 520                         ERR("Cannot show --help for `lttng-sessiond`");
 521                         perror("exec");
 522                 }
 523                 exit(ret ? EXIT_FAILURE : EXIT_SUCCESS);
 524         } else if (string_match(optname, "version") || opt == 'V') {
 525                 fprintf(stdout, "%s\n", VERSION);
 526                 exit(EXIT_SUCCESS);
 527         } else if (string_match(optname, "sig-parent") || opt == 'S') {
 528                 config.sig_parent = true;
 529         } else if (string_match(optname, "kconsumerd-err-sock")) {
 530                 if (!arg || *arg == '\0') {
 531                         ret = -EINVAL;
 532                         goto end;
 533                 }
 534                 if (lttng_is_setuid_setgid()) {
 535                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 536                                 "--kconsumerd-err-sock");
 537                 } else {
 538                         config_string_set(&config.kconsumerd_err_unix_sock_path,
 539                                         strdup(arg));
 540                         if (!config.kconsumerd_err_unix_sock_path.value) {
 541                                 ret = -ENOMEM;
 542                                 PERROR("strdup");
 543                         }
 544                 }
 545         } else if (string_match(optname, "kconsumerd-cmd-sock")) {
 546                 if (!arg || *arg == '\0') {
 547                         ret = -EINVAL;
 548                         goto end;
 549                 }
 550                 if (lttng_is_setuid_setgid()) {
 551                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 552                                 "--kconsumerd-cmd-sock");
 553                 } else {
 554                         config_string_set(&config.kconsumerd_cmd_unix_sock_path,
 555                                         strdup(arg));
 556                         if (!config.kconsumerd_cmd_unix_sock_path.value) {
 557                                 ret = -ENOMEM;
 558                                 PERROR("strdup");
 559                         }
 560                 }
 561         } else if (string_match(optname, "ustconsumerd64-err-sock")) {
 562                 if (!arg || *arg == '\0') {
 563                         ret = -EINVAL;
 564                         goto end;
 565                 }
 566                 if (lttng_is_setuid_setgid()) {
 567                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 568                                 "--ustconsumerd64-err-sock");
 569                 } else {
 570                         config_string_set(&config.consumerd64_err_unix_sock_path,
 571                                         strdup(arg));
 572                         if (!config.consumerd64_err_unix_sock_path.value) {
 573                                 ret = -ENOMEM;
 574                                 PERROR("strdup");
 575                         }
 576                 }
 577         } else if (string_match(optname, "ustconsumerd64-cmd-sock")) {
 578                 if (!arg || *arg == '\0') {
 579                         ret = -EINVAL;
 580                         goto end;
 581                 }
 582                 if (lttng_is_setuid_setgid()) {
 583                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 584                                 "--ustconsumerd64-cmd-sock");
 585                 } else {
 586                         config_string_set(&config.consumerd64_cmd_unix_sock_path,
 587                                         strdup(arg));
 588                         if (!config.consumerd64_cmd_unix_sock_path.value) {
 589                                 ret = -ENOMEM;
 590                                 PERROR("strdup");
 591                         }
 592                 }
 593         } else if (string_match(optname, "ustconsumerd32-err-sock")) {
 594                 if (!arg || *arg == '\0') {
 595                         ret = -EINVAL;
 596                         goto end;
 597                 }
 598                 if (lttng_is_setuid_setgid()) {
 599                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 600                                 "--ustconsumerd32-err-sock");
 601                 } else {
 602                         config_string_set(&config.consumerd32_err_unix_sock_path,
 603                                         strdup(arg));
 604                         if (!config.consumerd32_err_unix_sock_path.value) {
 605                                 ret = -ENOMEM;
 606                                 PERROR("strdup");
 607                         }
 608                 }
 609         } else if (string_match(optname, "ustconsumerd32-cmd-sock")) {
 610                 if (!arg || *arg == '\0') {
 611                         ret = -EINVAL;
 612                         goto end;
 613                 }
 614                 if (lttng_is_setuid_setgid()) {
 615                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 616                                 "--ustconsumerd32-cmd-sock");
 617                 } else {
 618                         config_string_set(&config.consumerd32_cmd_unix_sock_path,
 619                                         strdup(arg));
 620                         if (!config.consumerd32_cmd_unix_sock_path.value) {
 621                                 ret = -ENOMEM;
 622                                 PERROR("strdup");
 623                         }
 624                 }
 625         } else if (string_match(optname, "no-kernel")) {
 626                 config.no_kernel = true;
 627         } else if (string_match(optname, "quiet") || opt == 'q') {
 628                 config.quiet = true;
 629         } else if (string_match(optname, "verbose") || opt == 'v') {
 630                 /* Verbose level can increase using multiple -v */
 631                 if (arg) {
 632                         /* Value obtained from config file */
 633                         config.verbose = config_parse_value(arg);
 634                 } else {
 635                         /* -v used on command line */
 636                         config.verbose++;
 637                 }
 638                 /* Clamp value to [0, 3] */
 639                 config.verbose = config.verbose < 0 ? 0 :
 640                         (config.verbose <= 3 ? config.verbose : 3);
 641         } else if (string_match(optname, "verbose-consumer")) {
 642                 if (arg) {
 643                         config.verbose_consumer = config_parse_value(arg);
 644                 } else {
 645                         config.verbose_consumer++;
 646                 }
 647         } else if (string_match(optname, "consumerd32-path")) {
 648                 if (!arg || *arg == '\0') {
 649                         ret = -EINVAL;
 650                         goto end;
 651                 }
 652                 if (lttng_is_setuid_setgid()) {
 653                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 654                                 "--consumerd32-path");
 655                 } else {
 656                         config_string_set(&config.consumerd32_bin_path,
 657                                         strdup(arg));
 658                         if (!config.consumerd32_bin_path.value) {
 659                                 PERROR("strdup");
 660                                 ret = -ENOMEM;
 661                         }
 662                 }
 663         } else if (string_match(optname, "consumerd32-libdir")) {
 664                 if (!arg || *arg == '\0') {
 665                         ret = -EINVAL;
 666                         goto end;
 667                 }
 668                 if (lttng_is_setuid_setgid()) {
 669                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 670                                 "--consumerd32-libdir");
 671                 } else {
 672                         config_string_set(&config.consumerd32_lib_dir,
 673                                         strdup(arg));
 674                         if (!config.consumerd32_lib_dir.value) {
 675                                 PERROR("strdup");
 676                                 ret = -ENOMEM;
 677                         }
 678                 }
 679         } else if (string_match(optname, "consumerd64-path")) {
 680                 if (!arg || *arg == '\0') {
 681                         ret = -EINVAL;
 682                         goto end;
 683                 }
 684                 if (lttng_is_setuid_setgid()) {
 685                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 686                                 "--consumerd64-path");
 687                 } else {
 688                         config_string_set(&config.consumerd64_bin_path,
 689                                         strdup(arg));
 690                         if (!config.consumerd64_bin_path.value) {
 691                                 PERROR("strdup");
 692                                 ret = -ENOMEM;
 693                         }
 694                 }
 695         } else if (string_match(optname, "consumerd64-libdir")) {
 696                 if (!arg || *arg == '\0') {
 697                         ret = -EINVAL;
 698                         goto end;
 699                 }
 700                 if (lttng_is_setuid_setgid()) {
 701                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 702                                 "--consumerd64-libdir");
 703                 } else {
 704                         config_string_set(&config.consumerd64_lib_dir,
 705                                         strdup(arg));
 706                         if (!config.consumerd64_lib_dir.value) {
 707                                 PERROR("strdup");
 708                                 ret = -ENOMEM;
 709                         }
 710                 }
 711         } else if (string_match(optname, "pidfile") || opt == 'p') {
 712                 if (!arg || *arg == '\0') {
 713                         ret = -EINVAL;
 714                         goto end;
 715                 }
 716                 if (lttng_is_setuid_setgid()) {
 717                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 718                                 "-p, --pidfile");
 719                 } else {
 720                         config_string_set(&config.pid_file_path, strdup(arg));
 721                         if (!config.pid_file_path.value) {
 722                                 PERROR("strdup");
 723                                 ret = -ENOMEM;
 724                         }
 725                 }
 726         } else if (string_match(optname, "agent-tcp-port")) {
 727                 if (!arg || *arg == '\0') {
 728                         ret = -EINVAL;
 729                         goto end;
 730                 }
 731                 if (lttng_is_setuid_setgid()) {
 732                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 733                                 "--agent-tcp-port");
 734                 } else {
 735                         unsigned long v;
 736
 737                         errno = 0;
 738                         v = strtoul(arg, NULL, 0);
 739                         if (errno != 0 || !isdigit(arg[0])) {
 740                                 ERR("Wrong value in --agent-tcp-port parameter: %s", arg);
 741                                 return -1;
 742                         }
 743                         if (v == 0 || v >= 65535) {
 744                                 ERR("Port overflow in --agent-tcp-port parameter: %s", arg);
 745                                 return -1;
 746                         }
 747                         config.agent_tcp_port.begin = config.agent_tcp_port.end = (int) v;
 748                         DBG3("Agent TCP port set to non default: %i", (int) v);
 749                 }
 750         } else if (string_match(optname, "load") || opt == 'l') {
 751                 if (!arg || *arg == '\0') {
 752                         ret = -EINVAL;
 753                         goto end;
 754                 }
 755                 if (lttng_is_setuid_setgid()) {
 756                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 757                                 "-l, --load");
 758                 } else {
 759                         config_string_set(&config.load_session_path, strdup(arg));
 760                         if (!config.load_session_path.value) {
 761                                 PERROR("strdup");
 762                                 ret = -ENOMEM;
 763                         }
 764                 }
 765         } else if (string_match(optname, "kmod-probes")) {
 766                 if (!arg || *arg == '\0') {
 767                         ret = -EINVAL;
 768                         goto end;
 769                 }
 770                 if (lttng_is_setuid_setgid()) {
 771                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 772                                 "--kmod-probes");
 773                 } else {
 774                         config_string_set(&config.kmod_probes_list, strdup(arg));
 775                         if (!config.kmod_probes_list.value) {
 776                                 PERROR("strdup");
 777                                 ret = -ENOMEM;
 778                         }
 779                 }
 780         } else if (string_match(optname, "extra-kmod-probes")) {
 781                 if (!arg || *arg == '\0') {
 782                         ret = -EINVAL;
 783                         goto end;
 784                 }
 785                 if (lttng_is_setuid_setgid()) {
 786                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 787                                 "--extra-kmod-probes");
 788                 } else {
 789                         config_string_set(&config.kmod_extra_probes_list,
 790                                         strdup(arg));
 791                         if (!config.kmod_extra_probes_list.value) {
 792                                 PERROR("strdup");
 793                                 ret = -ENOMEM;
 794                         }
 795                 }
 796         } else if (string_match(optname, "config") || opt == 'f') {
 797                 /* This is handled in set_options() thus silent skip. */
 798                 goto end;
 799         } else {
 800                 /* Unknown option or other error.
 801                  * Error is printed by getopt, just return */
 802                 ret = -1;
 803         }
 804
 805 end:
 806         if (ret == -EINVAL) {
 807                 const char *opt_name = "unknown";
 808                 int i;
 809
 810                 for (i = 0; i < sizeof(long_options) / sizeof(struct option);
 811                         i++) {
 812                         if (opt == long_options[i].val) {
 813                                 opt_name = long_options[i].name;
 814                                 break;
 815                         }
 816                 }
 817
 818                 WARN("Invalid argument provided for option \"%s\", using default value.",
 819                         opt_name);
 820         }
 821
 822         return ret;
 823 }
 824
 825 /*
 826  * config_entry_handler_cb used to handle options read from a config file.
 827  * See config_entry_handler_cb comment in common/config/session-config.h for the
 828  * return value conventions.
 829  */
 830 static int config_entry_handler(const struct config_entry *entry, void *unused)
 831 {
 832         int ret = 0, i;
 833
 834         if (!entry || !entry->name || !entry->value) {
 835                 ret = -EINVAL;
 836                 goto end;
 837         }
 838
 839         /* Check if the option is to be ignored */
 840         for (i = 0; i < sizeof(config_ignore_options) / sizeof(char *); i++) {
 841                 if (!strcmp(entry->name, config_ignore_options[i])) {
 842                         goto end;
 843                 }
 844         }
 845
 846         for (i = 0; i < (sizeof(long_options) / sizeof(struct option)) - 1;
 847                 i++) {
 848
 849                 /* Ignore if not fully matched. */
 850                 if (strcmp(entry->name, long_options[i].name)) {
 851                         continue;
 852                 }
 853
 854                 /*
 855                  * If the option takes no argument on the command line, we have to
 856                  * check if the value is "true". We support non-zero numeric values,
 857                  * true, on and yes.
 858                  */
 859                 if (!long_options[i].has_arg) {
 860                         ret = config_parse_value(entry->value);
 861                         if (ret <= 0) {
 862                                 if (ret) {
 863                                         WARN("Invalid configuration value \"%s\" for option %s",
 864                                                         entry->value, entry->name);
 865                                 }
 866                                 /* False, skip boolean config option. */
 867                                 goto end;
 868                         }
 869                 }
 870
 871                 ret = set_option(long_options[i].val, entry->value, entry->name);
 872                 goto end;
 873         }
 874
 875         WARN("Unrecognized option \"%s\" in daemon configuration file.", entry->name);
 876
 877 end:
 878         return ret;
 879 }
 880
 881 /*
 882  * daemon configuration loading and argument parsing
 883  */
 884 static int set_options(int argc, char **argv)
 885 {
 886         int ret = 0, c = 0, option_index = 0;
 887         int orig_optopt = optopt, orig_optind = optind;
 888         char *optstring;
 889         const char *config_path = NULL;
 890
 891         optstring = utils_generate_optstring(long_options,
 892                         sizeof(long_options) / sizeof(struct option));
 893         if (!optstring) {
 894                 ret = -ENOMEM;
 895                 goto end;
 896         }
 897
 898         /* Check for the --config option */
 899         while ((c = getopt_long(argc, argv, optstring, long_options,
 900                                         &option_index)) != -1) {
 901                 if (c == '?') {
 902                         ret = -EINVAL;
 903                         goto end;
 904                 } else if (c != 'f') {
 905                         /* if not equal to --config option. */
 906                         continue;
 907                 }
 908
 909                 if (lttng_is_setuid_setgid()) {
 910                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 911                                 "-f, --config");
 912                 } else {
 913                         config_path = utils_expand_path(optarg);
 914                         if (!config_path) {
 915                                 ERR("Failed to resolve path: %s", optarg);
 916                         }
 917                 }
 918         }
 919
 920         ret = config_get_section_entries(config_path, config_section_name,
 921                         config_entry_handler, NULL);
 922         if (ret) {
 923                 if (ret > 0) {
 924                         ERR("Invalid configuration option at line %i", ret);
 925                         ret = -1;
 926                 }
 927                 goto end;
 928         }
 929
 930         /* Reset getopt's global state */
 931         optopt = orig_optopt;
 932         optind = orig_optind;
 933         while (1) {
 934                 option_index = -1;
 935                 /*
 936                  * getopt_long() will not set option_index if it encounters a
 937                  * short option.
 938                  */
 939                 c = getopt_long(argc, argv, optstring, long_options,
 940                                 &option_index);
 941                 if (c == -1) {
 942                         break;
 943                 }
 944
 945                 /*
 946                  * Pass NULL as the long option name if popt left the index
 947                  * unset.
 948                  */
 949                 ret = set_option(c, optarg,
 950                                 option_index < 0 ? NULL :
 951                                 long_options[option_index].name);
 952                 if (ret < 0) {
 953                         break;
 954                 }
 955         }
 956
 957 end:
 958         free(optstring);
 959         return ret;
 960 }
 961
 962 /*
 963  * Create lockfile using the rundir and return its fd.
 964  */
 965 static int create_lockfile(void)
 966 {
 967         return utils_create_lock_file(config.lock_file_path.value);
 968 }
 969
 970 /*
 971  * Check if the global socket is available, and if a daemon is answering at the
 972  * other side. If yes, error is returned.
 973  *
 974  * Also attempts to create and hold the lock file.
 975  */
 976 static int check_existing_daemon(void)
 977 {
 978         int ret = 0;
 979
 980         /* Is there anybody out there ? */
 981         if (lttng_session_daemon_alive()) {
 982                 ret = -EEXIST;
 983                 goto end;
 984         }
 985
 986         lockfile_fd = create_lockfile();
 987         if (lockfile_fd < 0) {
 988                 ret = -EEXIST;
 989                 goto end;
 990         }
 991 end:
 992         return ret;
 993 }
 994
 995 static void sessiond_cleanup_lock_file(void)
 996 {
 997         int ret;
 998
 999         /*
1000          * Cleanup lock file by deleting it and finaly closing it which will
1001          * release the file system lock.
1002          */
1003         if (lockfile_fd >= 0) {
1004                 ret = remove(config.lock_file_path.value);
1005                 if (ret < 0) {
1006                         PERROR("remove lock file");
1007                 }
1008                 ret = close(lockfile_fd);
1009                 if (ret < 0) {
1010                         PERROR("close lock file");
1011                 }
1012         }
1013 }
1014
1015 /*
1016  * Set the tracing group gid onto the client socket.
1017  *
1018  * Race window between mkdir and chown is OK because we are going from more
1019  * permissive (root.root) to less permissive (root.tracing).
1020  */
1021 static int set_permissions(char *rundir)
1022 {
1023         int ret;
1024         gid_t gid;
1025
1026         ret = utils_get_group_id(config.tracing_group_name.value, true, &gid);
1027         if (ret) {
1028                 /* Default to root group. */
1029                 gid = 0;
1030         }
1031
1032         /* Set lttng run dir */
1033         ret = chown(rundir, 0, gid);
1034         if (ret < 0) {
1035                 ERR("Unable to set group on %s", rundir);
1036                 PERROR("chown");
1037         }
1038
1039         /*
1040          * Ensure all applications and tracing group can search the run
1041          * dir. Allow everyone to read the directory, since it does not
1042          * buy us anything to hide its content.
1043          */
1044         ret = chmod(rundir, S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH);
1045         if (ret < 0) {
1046                 ERR("Unable to set permissions on %s", rundir);
1047                 PERROR("chmod");
1048         }
1049
1050         /* lttng client socket path */
1051         ret = chown(config.client_unix_sock_path.value, 0, gid);
1052         if (ret < 0) {
1053                 ERR("Unable to set group on %s", config.client_unix_sock_path.value);
1054                 PERROR("chown");
1055         }
1056
1057         /* kconsumer error socket path */
1058         ret = chown(kconsumer_data.err_unix_sock_path, 0, 0);
1059         if (ret < 0) {
1060                 ERR("Unable to set group on %s", kconsumer_data.err_unix_sock_path);
1061                 PERROR("chown");
1062         }
1063
1064         /* 64-bit ustconsumer error socket path */
1065         ret = chown(ustconsumer64_data.err_unix_sock_path, 0, 0);
1066         if (ret < 0) {
1067                 ERR("Unable to set group on %s", ustconsumer64_data.err_unix_sock_path);
1068                 PERROR("chown");
1069         }
1070
1071         /* 32-bit ustconsumer compat32 error socket path */
1072         ret = chown(ustconsumer32_data.err_unix_sock_path, 0, 0);
1073         if (ret < 0) {
1074                 ERR("Unable to set group on %s", ustconsumer32_data.err_unix_sock_path);
1075                 PERROR("chown");
1076         }
1077
1078         DBG("All permissions are set");
1079
1080         return ret;
1081 }
1082
1083 /*
1084  * Create the lttng run directory needed for all global sockets and pipe.
1085  */
1086 static int create_lttng_rundir(void)
1087 {
1088         int ret;
1089
1090         DBG3("Creating LTTng run directory: %s", config.rundir.value);
1091
1092         ret = mkdir(config.rundir.value, S_IRWXU);
1093         if (ret < 0) {
1094                 if (errno != EEXIST) {
1095                         ERR("Unable to create %s", config.rundir.value);
1096                         goto error;
1097                 } else {
1098                         ret = 0;
1099                 }
1100         }
1101
1102 error:
1103         return ret;
1104 }
1105
1106 /*
1107  * Setup sockets and directory needed by the consumerds' communication with the
1108  * session daemon.
1109  */
1110 static int set_consumer_sockets(struct consumer_data *consumer_data)
1111 {
1112         int ret;
1113         char *path = NULL;
1114
1115         switch (consumer_data->type) {
1116         case LTTNG_CONSUMER_KERNEL:
1117                 path = config.kconsumerd_path.value;
1118                 break;
1119         case LTTNG_CONSUMER64_UST:
1120                 path = config.consumerd64_path.value;
1121                 break;
1122         case LTTNG_CONSUMER32_UST:
1123                 path = config.consumerd32_path.value;
1124                 break;
1125         default:
1126                 ERR("Consumer type unknown");
1127                 ret = -EINVAL;
1128                 goto error;
1129         }
1130         assert(path);
1131
1132         DBG2("Creating consumer directory: %s", path);
1133
1134         ret = mkdir(path, S_IRWXU | S_IRGRP | S_IXGRP);
1135         if (ret < 0 && errno != EEXIST) {
1136                 PERROR("mkdir");
1137                 ERR("Failed to create %s", path);
1138                 goto error;
1139         }
1140         if (is_root) {
1141                 gid_t gid;
1142
1143                 ret = utils_get_group_id(config.tracing_group_name.value, true,
1144                                 &gid);
1145                 if (ret) {
1146                         /* Default to root group. */
1147                         gid = 0;
1148                 }
1149
1150                 ret = chown(path, 0, gid);
1151                 if (ret < 0) {
1152                         ERR("Unable to set group on %s", path);
1153                         PERROR("chown");
1154                         goto error;
1155                 }
1156         }
1157
1158         /* Create the consumerd error unix socket */
1159         consumer_data->err_sock =
1160                 lttcomm_create_unix_sock(consumer_data->err_unix_sock_path);
1161         if (consumer_data->err_sock < 0) {
1162                 ERR("Create unix sock failed: %s", consumer_data->err_unix_sock_path);
1163                 ret = -1;
1164                 goto error;
1165         }
1166
1167         /*
1168          * Set the CLOEXEC flag. Return code is useless because either way, the
1169          * show must go on.
1170          */
1171         ret = utils_set_fd_cloexec(consumer_data->err_sock);
1172         if (ret < 0) {
1173                 PERROR("utils_set_fd_cloexec");
1174                 /* continue anyway */
1175         }
1176
1177         /* File permission MUST be 660 */
1178         ret = chmod(consumer_data->err_unix_sock_path,
1179                         S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
1180         if (ret < 0) {
1181                 ERR("Set file permissions failed: %s", consumer_data->err_unix_sock_path);
1182                 PERROR("chmod");
1183                 goto error;
1184         }
1185
1186 error:
1187         return ret;
1188 }
1189
1190 /*
1191  * Signal handler for the daemon
1192  *
1193  * Simply stop all worker threads, leaving main() return gracefully after
1194  * joining all threads and calling cleanup().
1195  */
1196 static void sighandler(int sig)
1197 {
1198         switch (sig) {
1199         case SIGINT:
1200                 DBG("SIGINT caught");
1201                 stop_threads();
1202                 break;
1203         case SIGTERM:
1204                 DBG("SIGTERM caught");
1205                 stop_threads();
1206                 break;
1207         case SIGUSR1:
1208                 CMM_STORE_SHARED(recv_child_signal, 1);
1209                 break;
1210         default:
1211                 break;
1212         }
1213 }
1214
1215 /*
1216  * Setup signal handler for :
1217  *              SIGINT, SIGTERM, SIGPIPE
1218  */
1219 static int set_signal_handler(void)
1220 {
1221         int ret = 0;
1222         struct sigaction sa;
1223         sigset_t sigset;
1224
1225         if ((ret = sigemptyset(&sigset)) < 0) {
1226                 PERROR("sigemptyset");
1227                 return ret;
1228         }
1229
1230         sa.sa_mask = sigset;
1231         sa.sa_flags = 0;
1232
1233         sa.sa_handler = sighandler;
1234         if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
1235                 PERROR("sigaction");
1236                 return ret;
1237         }
1238
1239         if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
1240                 PERROR("sigaction");
1241                 return ret;
1242         }
1243
1244         if ((ret = sigaction(SIGUSR1, &sa, NULL)) < 0) {
1245                 PERROR("sigaction");
1246                 return ret;
1247         }
1248
1249         sa.sa_handler = SIG_IGN;
1250         if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
1251                 PERROR("sigaction");
1252                 return ret;
1253         }
1254
1255         DBG("Signal handler set for SIGTERM, SIGUSR1, SIGPIPE and SIGINT");
1256
1257         return ret;
1258 }
1259
1260 /*
1261  * Set open files limit to unlimited. This daemon can open a large number of
1262  * file descriptors in order to consume multiple kernel traces.
1263  */
1264 static void set_ulimit(void)
1265 {
1266         int ret;
1267         struct rlimit lim;
1268
1269         /* The kernel does not allow an infinite limit for open files */
1270         lim.rlim_cur = 65535;
1271         lim.rlim_max = 65535;
1272
1273         ret = setrlimit(RLIMIT_NOFILE, &lim);
1274         if (ret < 0) {
1275                 PERROR("failed to set open files limit");
1276         }
1277 }
1278
1279 static int write_pidfile(void)
1280 {
1281         return utils_create_pid_file(getpid(), config.pid_file_path.value);
1282 }
1283
1284 static int set_clock_plugin_env(void)
1285 {
1286         int ret = 0;
1287         char *env_value = NULL;
1288
1289         if (!config.lttng_ust_clock_plugin.value) {
1290                 goto end;
1291         }
1292
1293         ret = asprintf(&env_value, "LTTNG_UST_CLOCK_PLUGIN=%s",
1294                         config.lttng_ust_clock_plugin.value);
1295         if (ret < 0) {
1296                 PERROR("asprintf");
1297                 goto end;
1298         }
1299
1300         ret = putenv(env_value);
1301         if (ret) {
1302                 free(env_value);
1303                 PERROR("putenv of LTTNG_UST_CLOCK_PLUGIN");
1304                 goto end;
1305         }
1306
1307         DBG("Updated LTTNG_UST_CLOCK_PLUGIN environment variable to \"%s\"",
1308                         config.lttng_ust_clock_plugin.value);
1309 end:
1310         return ret;
1311 }
1312
1313 static void destroy_all_sessions_and_wait(void)
1314 {
1315         struct ltt_session *session, *tmp;
1316         struct ltt_session_list *session_list;
1317
1318         session_list = session_get_list();
1319         DBG("Initiating destruction of all sessions");
1320
1321         if (!session_list) {
1322                 return;
1323         }
1324
1325         session_lock_list();
1326         /* Initiate the destruction of all sessions. */
1327         cds_list_for_each_entry_safe(session, tmp,
1328                         &session_list->head, list) {
1329                 if (!session_get(session)) {
1330                         continue;
1331                 }
1332
1333                 session_lock(session);
1334                 if (session->destroyed) {
1335                         goto unlock_session;
1336                 }
1337                 (void) cmd_stop_trace(session);
1338                 (void) cmd_destroy_session(session, notification_thread_handle,
1339                                 NULL);
1340         unlock_session:
1341                 session_unlock(session);
1342                 session_put(session);
1343         }
1344         session_unlock_list();
1345
1346         /* Wait for the destruction of all sessions to complete. */
1347         DBG("Waiting for the destruction of all sessions to complete");
1348         session_list_wait_empty();
1349         DBG("Destruction of all sessions completed");
1350 }
1351
1352 static int run_as_worker_post_fork_cleanup(void *data)
1353 {
1354         struct sessiond_config *sessiond_config = data;
1355
1356         sessiond_config_fini(sessiond_config);
1357         return 0;
1358 }
1359
1360 static int launch_run_as_worker(const char *procname)
1361 {
1362         /*
1363          * Clean-up before forking the run-as worker. Any dynamically
1364          * allocated memory of which the worker is not aware will
1365          * be leaked as the process forks a run-as worker (and performs
1366          * no exec*()). The same would apply to any opened fd.
1367          */
1368         return run_as_create_worker(procname, run_as_worker_post_fork_cleanup,
1369                         &config);
1370 }
1371
1372 static void sessiond_uuid_log(void)
1373 {
1374         char uuid_str[UUID_STR_LEN];
1375
1376         lttng_uuid_to_str(sessiond_uuid, uuid_str);
1377         DBG("Starting lttng-sessiond {%s}", uuid_str);
1378 }
1379
1380 /*
1381  * main
1382  */
1383 int main(int argc, char **argv)
1384 {
1385         int ret = 0, retval = 0;
1386         const char *env_app_timeout;
1387         struct lttng_pipe *ust32_channel_monitor_pipe = NULL,
1388                         *ust64_channel_monitor_pipe = NULL,
1389                         *kernel_channel_monitor_pipe = NULL;
1390         struct lttng_thread *ht_cleanup_thread = NULL;
1391         struct timer_thread_parameters timer_thread_parameters;
1392         /* Rotation thread handle. */
1393         struct rotation_thread_handle *rotation_thread_handle = NULL;
1394         /* Queue of rotation jobs populated by the sessiond-timer. */
1395         struct rotation_thread_timer_queue *rotation_timer_queue = NULL;
1396         struct lttng_thread *client_thread = NULL;
1397         struct lttng_thread *notification_thread = NULL;
1398         struct lttng_thread *register_apps_thread = NULL;
1399
1400         init_kernel_workarounds();
1401
1402         rcu_register_thread();
1403
1404         if (set_signal_handler()) {
1405                 retval = -1;
1406                 goto exit_set_signal_handler;
1407         }
1408
1409         if (timer_signal_init()) {
1410                 retval = -1;
1411                 goto exit_set_signal_handler;
1412         }
1413
1414         page_size = sysconf(_SC_PAGESIZE);
1415         if (page_size < 0) {
1416                 PERROR("sysconf _SC_PAGESIZE");
1417                 page_size = LONG_MAX;
1418                 WARN("Fallback page size to %ld", page_size);
1419         }
1420
1421         ret = sessiond_config_init(&config);
1422         if (ret) {
1423                 retval = -1;
1424                 goto exit_set_signal_handler;
1425         }
1426
1427         /*
1428          * Init config from environment variables.
1429          * Command line option override env configuration per-doc. Do env first.
1430          */
1431         sessiond_config_apply_env_config(&config);
1432
1433         /*
1434          * Parse arguments and load the daemon configuration file.
1435          *
1436          * We have an exit_options exit path to free memory reserved by
1437          * set_options. This is needed because the rest of sessiond_cleanup()
1438          * depends on ht_cleanup_thread, which depends on lttng_daemonize, which
1439          * depends on set_options.
1440          */
1441         progname = argv[0];
1442         if (set_options(argc, argv)) {
1443                 retval = -1;
1444                 goto exit_options;
1445         }
1446
1447         /*
1448          * Resolve all paths received as arguments, configuration option, or
1449          * through environment variable as absolute paths. This is necessary
1450          * since daemonizing causes the sessiond's current working directory
1451          * to '/'.
1452          */
1453         ret = sessiond_config_resolve_paths(&config);
1454         if (ret) {
1455                 goto exit_options;
1456         }
1457
1458         /* Apply config. */
1459         lttng_opt_verbose = config.verbose;
1460         lttng_opt_quiet = config.quiet;
1461         kconsumer_data.err_unix_sock_path =
1462                         config.kconsumerd_err_unix_sock_path.value;
1463         kconsumer_data.cmd_unix_sock_path =
1464                         config.kconsumerd_cmd_unix_sock_path.value;
1465         ustconsumer32_data.err_unix_sock_path =
1466                         config.consumerd32_err_unix_sock_path.value;
1467         ustconsumer32_data.cmd_unix_sock_path =
1468                         config.consumerd32_cmd_unix_sock_path.value;
1469         ustconsumer64_data.err_unix_sock_path =
1470                         config.consumerd64_err_unix_sock_path.value;
1471         ustconsumer64_data.cmd_unix_sock_path =
1472                         config.consumerd64_cmd_unix_sock_path.value;
1473         set_clock_plugin_env();
1474
1475         sessiond_config_log(&config);
1476         sessiond_uuid_log();
1477
1478         if (create_lttng_rundir()) {
1479                 retval = -1;
1480                 goto exit_options;
1481         }
1482
1483         /* Abort launch if a session daemon is already running. */
1484         if (check_existing_daemon()) {
1485                 ERR("A session daemon is already running.");
1486                 retval = -1;
1487                 goto exit_options;
1488         }
1489
1490         /* Daemonize */
1491         if (config.daemonize || config.background) {
1492                 int i;
1493
1494                 ret = lttng_daemonize(&child_ppid, &recv_child_signal,
1495                         !config.background);
1496                 if (ret < 0) {
1497                         retval = -1;
1498                         goto exit_options;
1499                 }
1500
1501                 /*
1502                  * We are in the child. Make sure all other file descriptors are
1503                  * closed, in case we are called with more opened file
1504                  * descriptors than the standard ones and the lock file.
1505                  */
1506                 for (i = 3; i < sysconf(_SC_OPEN_MAX); i++) {
1507                         if (i == lockfile_fd) {
1508                                 continue;
1509                         }
1510                         (void) close(i);
1511                 }
1512         }
1513
1514         if (launch_run_as_worker(argv[0]) < 0) {
1515                 goto exit_create_run_as_worker_cleanup;
1516         }
1517
1518         /*
1519          * Starting from here, we can create threads. This needs to be after
1520          * lttng_daemonize due to RCU.
1521          */
1522
1523         /*
1524          * Initialize the health check subsystem. This call should set the
1525          * appropriate time values.
1526          */
1527         health_sessiond = health_app_create(NR_HEALTH_SESSIOND_TYPES);
1528         if (!health_sessiond) {
1529                 PERROR("health_app_create error");
1530                 retval = -1;
1531                 goto stop_threads;
1532         }
1533
1534         /* Create thread to clean up RCU hash tables */
1535         ht_cleanup_thread = launch_ht_cleanup_thread();
1536         if (!ht_cleanup_thread) {
1537                 retval = -1;
1538                 goto stop_threads;
1539         }
1540
1541         /* Create thread quit pipe */
1542         if (sessiond_init_thread_quit_pipe()) {
1543                 retval = -1;
1544                 goto stop_threads;
1545         }
1546
1547         /* Check if daemon is UID = 0 */
1548         is_root = !getuid();
1549         if (is_root) {
1550                 /* Create global run dir with root access */
1551
1552                 kernel_channel_monitor_pipe = lttng_pipe_open(0);
1553                 if (!kernel_channel_monitor_pipe) {
1554                         ERR("Failed to create kernel consumer channel monitor pipe");
1555                         retval = -1;
1556                         goto stop_threads;
1557                 }
1558                 kconsumer_data.channel_monitor_pipe =
1559                                 lttng_pipe_release_writefd(
1560                                         kernel_channel_monitor_pipe);
1561                 if (kconsumer_data.channel_monitor_pipe < 0) {
1562                         retval = -1;
1563                         goto stop_threads;
1564                 }
1565         }
1566
1567         /* Set consumer initial state */
1568         kernel_consumerd_state = CONSUMER_STOPPED;
1569         ust_consumerd_state = CONSUMER_STOPPED;
1570
1571         ust32_channel_monitor_pipe = lttng_pipe_open(0);
1572         if (!ust32_channel_monitor_pipe) {
1573                 ERR("Failed to create 32-bit user space consumer channel monitor pipe");
1574                 retval = -1;
1575                 goto stop_threads;
1576         }
1577         ustconsumer32_data.channel_monitor_pipe = lttng_pipe_release_writefd(
1578                         ust32_channel_monitor_pipe);
1579         if (ustconsumer32_data.channel_monitor_pipe < 0) {
1580                 retval = -1;
1581                 goto stop_threads;
1582         }
1583
1584         /*
1585          * The rotation_thread_timer_queue structure is shared between the
1586          * sessiond timer thread and the rotation thread. The main thread keeps
1587          * its ownership and destroys it when both threads have been joined.
1588          */
1589         rotation_timer_queue = rotation_thread_timer_queue_create();
1590         if (!rotation_timer_queue) {
1591                 retval = -1;
1592                 goto stop_threads;
1593         }
1594         timer_thread_parameters.rotation_thread_job_queue =
1595                         rotation_timer_queue;
1596
1597         ust64_channel_monitor_pipe = lttng_pipe_open(0);
1598         if (!ust64_channel_monitor_pipe) {
1599                 ERR("Failed to create 64-bit user space consumer channel monitor pipe");
1600                 retval = -1;
1601                 goto stop_threads;
1602         }
1603         ustconsumer64_data.channel_monitor_pipe = lttng_pipe_release_writefd(
1604                         ust64_channel_monitor_pipe);
1605         if (ustconsumer64_data.channel_monitor_pipe < 0) {
1606                 retval = -1;
1607                 goto stop_threads;
1608         }
1609
1610         /*
1611          * Init UST app hash table. Alloc hash table before this point since
1612          * cleanup() can get called after that point.
1613          */
1614         if (ust_app_ht_alloc()) {
1615                 ERR("Failed to allocate UST app hash table");
1616                 retval = -1;
1617                 goto stop_threads;
1618         }
1619
1620         /*
1621          * Initialize agent app hash table. We allocate the hash table here
1622          * since cleanup() can get called after this point.
1623          */
1624         if (agent_app_ht_alloc()) {
1625                 ERR("Failed to allocate Agent app hash table");
1626                 retval = -1;
1627                 goto stop_threads;
1628         }
1629
1630         /*
1631          * These actions must be executed as root. We do that *after* setting up
1632          * the sockets path because we MUST make the check for another daemon using
1633          * those paths *before* trying to set the kernel consumer sockets and init
1634          * kernel tracer.
1635          */
1636         if (is_root) {
1637                 if (set_consumer_sockets(&kconsumer_data)) {
1638                         retval = -1;
1639                         goto stop_threads;
1640                 }
1641
1642                 /* Setup kernel tracer */
1643                 if (!config.no_kernel) {
1644                         init_kernel_tracer();
1645                         if (kernel_tracer_fd >= 0) {
1646                                 ret = syscall_init_table();
1647                                 if (ret < 0) {
1648                                         ERR("Unable to populate syscall table. "
1649                                                 "Syscall tracing won't work "
1650                                                 "for this session daemon.");
1651                                 }
1652                         }
1653                 }
1654
1655                 /* Set ulimit for open files */
1656                 set_ulimit();
1657         }
1658         /* init lttng_fd tracking must be done after set_ulimit. */
1659         lttng_fd_init();
1660
1661         if (set_consumer_sockets(&ustconsumer64_data)) {
1662                 retval = -1;
1663                 goto stop_threads;
1664         }
1665
1666         if (set_consumer_sockets(&ustconsumer32_data)) {
1667                 retval = -1;
1668                 goto stop_threads;
1669         }
1670
1671         /* Get parent pid if -S, --sig-parent is specified. */
1672         if (config.sig_parent) {
1673                 ppid = getppid();
1674         }
1675
1676         /* Setup the kernel pipe for waking up the kernel thread */
1677         if (is_root && !config.no_kernel) {
1678                 if (utils_create_pipe_cloexec(kernel_poll_pipe)) {
1679                         retval = -1;
1680                         goto stop_threads;
1681                 }
1682         }
1683
1684         /* Setup the thread apps communication pipe. */
1685         if (utils_create_pipe_cloexec(apps_cmd_pipe)) {
1686                 retval = -1;
1687                 goto stop_threads;
1688         }
1689
1690         /* Setup the thread apps notify communication pipe. */
1691         if (utils_create_pipe_cloexec(apps_cmd_notify_pipe)) {
1692                 retval = -1;
1693                 goto stop_threads;
1694         }
1695
1696         /* Initialize global buffer per UID and PID registry. */
1697         buffer_reg_init_uid_registry();
1698         buffer_reg_init_pid_registry();
1699
1700         /* Init UST command queue. */
1701         cds_wfcq_init(&ust_cmd_queue.head, &ust_cmd_queue.tail);
1702
1703         cmd_init();
1704
1705         /* Check for the application socket timeout env variable. */
1706         env_app_timeout = getenv(DEFAULT_APP_SOCKET_TIMEOUT_ENV);
1707         if (env_app_timeout) {
1708                 config.app_socket_timeout = atoi(env_app_timeout);
1709         } else {
1710                 config.app_socket_timeout = DEFAULT_APP_SOCKET_RW_TIMEOUT;
1711         }
1712
1713         ret = write_pidfile();
1714         if (ret) {
1715                 ERR("Error in write_pidfile");
1716                 retval = -1;
1717                 goto stop_threads;
1718         }
1719
1720         /* Initialize communication library */
1721         lttcomm_init();
1722         /* Initialize TCP timeout values */
1723         lttcomm_inet_init();
1724
1725         /* Create health-check thread. */
1726         if (!launch_health_management_thread()) {
1727                 retval = -1;
1728                 goto stop_threads;
1729         }
1730
1731         /* notification_thread_data acquires the pipes' read side. */
1732         notification_thread_handle = notification_thread_handle_create(
1733                         ust32_channel_monitor_pipe,
1734                         ust64_channel_monitor_pipe,
1735                         kernel_channel_monitor_pipe);
1736         if (!notification_thread_handle) {
1737                 retval = -1;
1738                 ERR("Failed to create notification thread shared data");
1739                 goto stop_threads;
1740         }
1741
1742         /* Create notification thread. */
1743         notification_thread = launch_notification_thread(
1744                         notification_thread_handle);
1745         if (!notification_thread) {
1746                 retval = -1;
1747                 goto stop_threads;
1748         }
1749
1750         /* Create timer thread. */
1751         if (!launch_timer_thread(&timer_thread_parameters)) {
1752                 retval = -1;
1753                 goto stop_threads;
1754         }
1755
1756         /* rotation_thread_data acquires the pipes' read side. */
1757         rotation_thread_handle = rotation_thread_handle_create(
1758                         rotation_timer_queue,
1759                         notification_thread_handle);
1760         if (!rotation_thread_handle) {
1761                 retval = -1;
1762                 ERR("Failed to create rotation thread shared data");
1763                 stop_threads();
1764                 goto stop_threads;
1765         }
1766
1767         /* Create rotation thread. */
1768         if (!launch_rotation_thread(rotation_thread_handle)) {
1769                 retval = -1;
1770                 goto stop_threads;
1771         }
1772
1773         /* Create thread to manage the client socket */
1774         client_thread = launch_client_thread();
1775         if (!client_thread) {
1776                 retval = -1;
1777                 goto stop_threads;
1778         }
1779
1780         /* Set credentials of the client socket and rundir */
1781         if (is_root && set_permissions(config.rundir.value)) {
1782                 retval = -1;
1783                 goto stop_threads;
1784         }
1785
1786         if (!launch_ust_dispatch_thread(&ust_cmd_queue, apps_cmd_pipe[1],
1787                         apps_cmd_notify_pipe[1])) {
1788                 retval = -1;
1789                 goto stop_threads;
1790         }
1791
1792         /* Create thread to manage application registration. */
1793         register_apps_thread = launch_application_registration_thread(
1794                         &ust_cmd_queue);
1795         if (!register_apps_thread) {
1796                 retval = -1;
1797                 goto stop_threads;
1798         }
1799
1800         /* Create thread to manage application socket */
1801         if (!launch_application_management_thread(apps_cmd_pipe[0])) {
1802                 retval = -1;
1803                 goto stop_threads;
1804         }
1805
1806         /* Create thread to manage application notify socket */
1807         if (!launch_application_notification_thread(apps_cmd_notify_pipe[0])) {
1808                 retval = -1;
1809                 goto stop_threads;
1810         }
1811
1812         /* Create agent management thread. */
1813         if (!launch_agent_management_thread()) {
1814                 retval = -1;
1815                 goto stop_threads;
1816         }
1817
1818         /* Don't start this thread if kernel tracing is not requested nor root */
1819         if (is_root && !config.no_kernel) {
1820                 /* Create kernel thread to manage kernel event */
1821                 if (!launch_kernel_management_thread(kernel_poll_pipe[0])) {
1822                         retval = -1;
1823                         goto stop_threads;
1824                 }
1825         }
1826
1827         /* Load sessions. */
1828         ret = config_load_session(config.load_session_path.value,
1829                         NULL, 1, 1, NULL);
1830         if (ret) {
1831                 ERR("Session load failed: %s", error_get_str(ret));
1832                 retval = -1;
1833                 goto stop_threads;
1834         }
1835
1836         /* Initialization completed. */
1837         sessiond_signal_parents();
1838
1839         /*
1840          * This is where we start awaiting program completion (e.g. through
1841          * signal that asks threads to teardown).
1842          */
1843
1844         /* Initiate teardown once activity occurs on the quit pipe. */
1845         sessiond_wait_for_quit_pipe(-1U);
1846
1847 stop_threads:
1848         /*
1849          * Ensure that the client thread is no longer accepting new commands,
1850          * which could cause new sessions to be created.
1851          */
1852         if (client_thread) {
1853                 lttng_thread_shutdown(client_thread);
1854                 lttng_thread_put(client_thread);
1855         }
1856
1857         destroy_all_sessions_and_wait();
1858
1859         if (register_apps_thread) {
1860                 lttng_thread_shutdown(register_apps_thread);
1861                 lttng_thread_put(register_apps_thread);
1862         }
1863         lttng_thread_list_shutdown_orphans();
1864
1865         /*
1866          * Wait for all pending call_rcu work to complete before tearing
1867          * down data structures. call_rcu worker may be trying to
1868          * perform lookups in those structures.
1869          */
1870         rcu_barrier();
1871         /*
1872          * sessiond_cleanup() is called when no other thread is running, except
1873          * the ht_cleanup thread, which is needed to destroy the hash tables.
1874          */
1875         rcu_thread_online();
1876         sessiond_cleanup();
1877
1878         if (notification_thread) {
1879                 lttng_thread_shutdown(notification_thread);
1880                 lttng_thread_put(notification_thread);
1881         }
1882
1883         /*
1884          * Ensure all prior call_rcu are done. call_rcu callbacks may push
1885          * hash tables to the ht_cleanup thread. Therefore, we ensure that
1886          * the queue is empty before shutting down the clean-up thread.
1887          */
1888         rcu_barrier();
1889
1890         if (ht_cleanup_thread) {
1891                 lttng_thread_shutdown(ht_cleanup_thread);
1892                 lttng_thread_put(ht_cleanup_thread);
1893         }
1894
1895         rcu_thread_offline();
1896         rcu_unregister_thread();
1897
1898         if (rotation_thread_handle) {
1899                 rotation_thread_handle_destroy(rotation_thread_handle);
1900         }
1901
1902         /*
1903          * After the rotation and timer thread have quit, we can safely destroy
1904          * the rotation_timer_queue.
1905          */
1906         rotation_thread_timer_queue_destroy(rotation_timer_queue);
1907         /*
1908          * The teardown of the notification system is performed after the
1909          * session daemon's teardown in order to allow it to be notified
1910          * of the active session and channels at the moment of the teardown.
1911          */
1912         if (notification_thread_handle) {
1913                 notification_thread_handle_destroy(notification_thread_handle);
1914         }
1915         lttng_pipe_destroy(ust32_channel_monitor_pipe);
1916         lttng_pipe_destroy(ust64_channel_monitor_pipe);
1917         lttng_pipe_destroy(kernel_channel_monitor_pipe);
1918
1919         health_app_destroy(health_sessiond);
1920 exit_create_run_as_worker_cleanup:
1921 exit_options:
1922         sessiond_cleanup_lock_file();
1923         sessiond_cleanup_options();
1924
1925 exit_set_signal_handler:
1926         if (!retval) {
1927                 exit(EXIT_SUCCESS);
1928         } else {
1929                 exit(EXIT_FAILURE);
1930         }
1931 }