src/main.c

   1 #ifdef HAVE_CONFIG_H
   2 #include <config.h>
   3 #endif
   4 #include <errno.h>
   5 #include <getopt.h>
   6 #include <pthread.h>
   7 #include <signal.h>
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10 #include <string.h>
  11 #include <sys/mman.h>
  12 #include <sys/prctl.h>
  13 #include <sys/wait.h>
  14 #include <syslog.h>
  15 #include <unistd.h>
  16
  17 #include "appconfig.h"
  18 #include "common.h"
  19 #include "daemon.h"
  20 #include "log.h"
  21 #include "popen.h"
  22 #include "rrd.h"
  23 #include "rrd2json.h"
  24 #include "web_client.h"
  25 #include "web_server.h"
  26
  27 #include "unit_test.h"
  28
  29 #include "plugin_checks.h"
  30 #include "plugin_idlejitter.h"
  31 #include "plugin_nfacct.h"
  32 #include "registry.h"
  33 #include "plugin_proc.h"
  34 #include "plugin_tc.h"
  35 #include "plugins_d.h"
  36
  37 #include "main.h"
  38
  39 extern void *cgroups_main(void *ptr);
  40
  41 volatile sig_atomic_t netdata_exit = 0;
  42
  43 void netdata_cleanup_and_exit(int ret)
  44 {
  45         netdata_exit = 1;
  46         rrdset_save_all();
  47         // kill_childs();
  48
  49         // let it log a few more error messages
  50         error_log_limit_reset();
  51
  52         if(pidfd != -1) {
  53                 if(ftruncate(pidfd, 0) != 0)
  54                         error("Cannot truncate pidfile '%s'.", pidfile);
  55
  56                 close(pidfd);
  57                 pidfd = -1;
  58         }
  59
  60         if(pidfile[0]) {
  61                 if(unlink(pidfile) != 0)
  62                         error("Cannot unlink pidfile '%s'.", pidfile);
  63         }
  64
  65         info("NetData exiting. Bye bye...");
  66         exit(ret);
  67 }
  68
  69 struct netdata_static_thread {
  70         char *name;
  71
  72         char *config_section;
  73         char *config_name;
  74
  75         int enabled;
  76
  77         pthread_t *thread;
  78
  79         void (*init_routine) (void);
  80         void *(*start_routine) (void *);
  81 };
  82
  83 struct netdata_static_thread static_threads[] = {
  84         {"tc",                  "plugins",      "tc",                   1, NULL, NULL,  tc_main},
  85         {"idlejitter",  "plugins",      "idlejitter",   1, NULL, NULL,  cpuidlejitter_main},
  86         {"proc",                "plugins",      "proc",                 1, NULL, NULL,  proc_main},
  87         {"cgroups",             "plugins",      "cgroups",              1, NULL, NULL,  cgroups_main},
  88
  89 #ifdef INTERNAL_PLUGIN_NFACCT
  90         // nfacct requires root access
  91         // so, we build it as an external plugin with setuid to root
  92         {"nfacct",              "plugins",      "nfacct",               1, NULL, NULL,  nfacct_main},
  93 #endif
  94
  95         {"plugins.d",   NULL,           NULL,                   1, NULL, NULL,  pluginsd_main},
  96         {"check",               "plugins",      "checks",               0, NULL, NULL,  checks_main},
  97         {"web",                 NULL,           NULL,                   1, NULL, NULL,  socket_listen_main},
  98         {NULL,                  NULL,           NULL,                   0, NULL, NULL,  NULL}
  99 };
 100
 101 int killpid(pid_t pid, int sig)
 102 {
 103         int ret = -1;
 104         debug(D_EXIT, "Request to kill pid %d", pid);
 105
 106         errno = 0;
 107         if(kill(pid, 0) == -1) {
 108                 switch(errno) {
 109                         case ESRCH:
 110                                 error("Request to kill pid %d, but it is not running.", pid);
 111                                 break;
 112
 113                         case EPERM:
 114                                 error("Request to kill pid %d, but I do not have enough permissions.", pid);
 115                                 break;
 116
 117                         default:
 118                                 error("Request to kill pid %d, but I received an error.", pid);
 119                                 break;
 120                 }
 121         }
 122         else {
 123                 errno = 0;
 124                 ret = kill(pid, sig);
 125                 if(ret == -1) {
 126                         switch(errno) {
 127                                 case ESRCH:
 128                                         error("Cannot kill pid %d, but it is not running.", pid);
 129                                         break;
 130
 131                                 case EPERM:
 132                                         error("Cannot kill pid %d, but I do not have enough permissions.", pid);
 133                                         break;
 134
 135                                 default:
 136                                         error("Cannot kill pid %d, but I received an error.", pid);
 137                                         break;
 138                         }
 139                 }
 140         }
 141
 142         return ret;
 143 }
 144
 145 void kill_childs()
 146 {
 147         siginfo_t info;
 148
 149         struct web_client *w;
 150         for(w = web_clients; w ; w = w->next) {
 151                 debug(D_EXIT, "Stopping web client %s", w->client_ip);
 152                 pthread_cancel(w->thread);
 153                 pthread_join(w->thread, NULL);
 154         }
 155
 156         int i;
 157         for (i = 0; static_threads[i].name != NULL ; i++) {
 158                 if(static_threads[i].thread) {
 159                         debug(D_EXIT, "Stopping %s thread", static_threads[i].name);
 160                         pthread_cancel(*static_threads[i].thread);
 161                         pthread_join(*static_threads[i].thread, NULL);
 162                         static_threads[i].thread = NULL;
 163                 }
 164         }
 165
 166         if(tc_child_pid) {
 167                 info("Killing tc-qos-helper procees");
 168                 if(killpid(tc_child_pid, SIGTERM) != -1)
 169                         waitid(P_PID, (id_t) tc_child_pid, &info, WEXITED);
 170         }
 171         tc_child_pid = 0;
 172
 173         struct plugind *cd;
 174         for(cd = pluginsd_root ; cd ; cd = cd->next) {
 175                 debug(D_EXIT, "Stopping %s plugin thread", cd->id);
 176                 pthread_cancel(cd->thread);
 177                 pthread_join(cd->thread, NULL);
 178
 179                 if(cd->pid && !cd->obsolete) {
 180                         debug(D_EXIT, "killing %s plugin process", cd->id);
 181                         if(killpid(cd->pid, SIGTERM) != -1)
 182                                 waitid(P_PID, (id_t) cd->pid, &info, WEXITED);
 183                 }
 184         }
 185
 186         // if, for any reason there is any child exited
 187         // catch it here
 188         waitid(P_PID, 0, &info, WEXITED|WNOHANG);
 189
 190         debug(D_EXIT, "All threads/childs stopped.");
 191 }
 192
 193 struct option_def options[] = {
 194         // opt description                                                       arg name                     default value
 195         {'c', "Load alternate configuration file",                               "config_file",                          CONFIG_DIR "/" CONFIG_FILENAME},
 196         {'D', "Disable fork into background",                                    NULL,                                   NULL},
 197         {'h', "Display help message",                                            NULL,                                   NULL},
 198         {'P', "File to save a pid while running",                                "FILE",                                 NULL},
 199         {'p', "Port to listen. Can be from 1 to 65535.",                         "port_number",                          "19999"},
 200         {'s', "Path to access host /proc and /sys when running in a container.", "PATH",                                 NULL},
 201         {'t', "The frequency in seconds, for data collection. \
 202                 Same as 'update every' config file option.",                         "seconds",                              "1"},
 203         {'l', "The number of entries the netdata daemon will keep in memory \
 204                 for each chart dimension. Same as 'history config file option.",     "lines_to_save",                        NULL},
 205         {'u', "System username to run as.",                                      "username",                             "netdata"},
 206         {'v', "Version of the program",                                          NULL,                                   NULL},
 207         {'W', "vendor options.",                                                 "stacksize=<size>|unittest|debug_flag", NULL},
 208 };
 209
 210 void help(int exitcode) {
 211         FILE *stream;
 212         if(exitcode == 0)
 213                 stream = stdout;
 214         else
 215                 stream = stderr;
 216
 217         int num_opts = sizeof(options) / sizeof(struct option_def);
 218         int i;
 219         int max_len_arg = 0;
 220
 221         // Compute maximum argument length
 222         for( i = 0; i < num_opts; i++ ) {
 223                 if(options[i].arg_name) {
 224                         int len_arg = strlen(options[i].arg_name);
 225                         if(len_arg > max_len_arg) max_len_arg = len_arg;
 226                 }
 227         }
 228
 229         fprintf(stream, "SYNOPSIS: netdata [options]\n");
 230         fprintf(stream, "\n");
 231         fprintf(stream, "Options:\n");
 232
 233         // Output options description.
 234         for( i = 0; i < num_opts; i++ ) {
 235                 fprintf(stream, "  -%c %-*s  %s", options[i].val, max_len_arg, options[i].arg_name ? options[i].arg_name : "", options[i].description);
 236                 if(options[i].default_value) {
 237                         fprintf(stream, " Default: %s\n", options[i].default_value);
 238                 } else {
 239                         fprintf(stream, "\n");
 240                 }
 241         }
 242
 243         fflush(stream);
 244         exit(exitcode);
 245 }
 246
 247
 248 int main(int argc, char **argv)
 249 {
 250         int i;
 251         int config_loaded = 0;
 252         int dont_fork = 0;
 253         size_t wanted_stacksize = 0, stacksize = 0;
 254         pthread_attr_t attr;
 255
 256         // global initialization
 257         get_HZ();
 258
 259         // set the name for logging
 260         program_name = "netdata";
 261
 262         // parse command line.
 263
 264         // parse depercated options
 265         // TODO: Remove this block with the next major release.
 266         {
 267                 void remove_option(int opt_index, int *argc, char **argv) {
 268                         int i = opt_index;
 269                         // remove the options.
 270                         do {
 271                                 *argc = *argc - 1;
 272                                 for(i = opt_index; i < *argc; i++) {
 273                                         argv[i] = argv[i+1];
 274                                 }
 275                                 i = opt_index;
 276                         } while(argv[i][0] != '-' && opt_index >= *argc);
 277                 }
 278
 279                 i = 1;
 280                 while(i < argc) {
 281                         if(strcmp(argv[i], "-pidfile") == 0 && (i+1) < argc) {
 282                                 strncpyz(pidfile, argv[i+1], FILENAME_MAX);
 283                                 fprintf(stderr, "%s: deprecate option -- %s -- please use -P instead.\n", argv[0], argv[i]);
 284                                 remove_option(i, &argc, argv);
 285                         }
 286                         else if(strcmp(argv[i], "-nodaemon") == 0 || strcmp(argv[i], "-nd") == 0) {
 287                                 dont_fork = 1;
 288                                 fprintf(stderr, "%s: deprecate option -- %s -- please use -D instead.\n ", argv[0], argv[i]);
 289                                 remove_option(i, &argc, argv);
 290                         }
 291                         else if(strcmp(argv[i], "-ch") == 0 && (i+1) < argc) {
 292                                 config_set("global", "host access prefix", argv[i+1]);
 293                                 fprintf(stderr, "%s: deprecate option -- %s -- please use -s instead.\n", argv[0], argv[i]);
 294                                 remove_option(i, &argc, argv);
 295                         }
 296                         else i++;
 297                 }
 298         }
 299
 300         // parse options
 301         {
 302                 int num_opts = sizeof(options) / sizeof(struct option_def);
 303                 char optstring[(num_opts * 2) + 1];
 304
 305                 int string_i = 0;
 306                 for( i = 0; i < num_opts; i++ ) {
 307                         optstring[string_i] = options[i].val;
 308                         string_i++;
 309                         if(options[i].arg_name) {
 310                                 optstring[string_i] = ':';
 311                                 string_i++;
 312                         }
 313                 }
 314
 315                 int opt;
 316                 while( (opt = getopt(argc, argv, optstring)) != -1 ) {
 317                         switch(opt) {
 318                                 case 'c':
 319                                         if(load_config(optarg, 1) != 1) {
 320                                                 error("Cannot load configuration file %s.", optarg);
 321                                                 exit(1);
 322                                         }
 323                                         else {
 324                                                 debug(D_OPTIONS, "Configuration loaded from %s.", optarg);
 325                                                 config_loaded = 1;
 326                                         }
 327                                         break;
 328                                 case 'D':
 329                                         dont_fork = 1;
 330                                         break;
 331                                 case 'h':
 332                                         help(0);
 333                                         break;
 334                                 case 'P':
 335                                         strncpy(pidfile, optarg, FILENAME_MAX);
 336                                         pidfile[FILENAME_MAX] = '\0';
 337                                         break;
 338                                 case 'p':
 339                                         config_set("global", "port", optarg);
 340                                         break;
 341                                 case 's':
 342                                         config_set("global", "host access prefix", optarg);
 343                                         break;
 344                                 case 't':
 345                                         config_set("global", "update every", optarg);
 346                                         break;
 347                                 case 'u':
 348                                         config_set("global", "run as user", optarg);
 349                                         break;
 350                                 case 'v':
 351                                         // TODO: Outsource version to makefile which can compute version from git.
 352                                         printf("netdata 1.1.0\n");
 353                                         return 0;
 354                                         break;
 355                                 case 'l':
 356                                         config_set("global", "history", optarg);
 357                                         break;
 358                                 case 'W':
 359                                         {
 360                                                 char* stacksize = "stacksize=";
 361                                                 char* debug_flags_string = "debug_flags=";
 362                                                 if(strcmp(optarg, "unittest") == 0) {
 363                                                         rrd_update_every = 1;
 364                                                         if(run_all_mockup_tests()) exit(1);
 365                                                         if(unit_test_storage()) exit(1);
 366                                                         fprintf(stderr, "\n\nALL TESTS PASSED\n\n");
 367                                                         exit(0);
 368                                                 } else if(strncmp(optarg, stacksize, strlen(stacksize)) == 0) {
 369                                                         optarg += strlen(stacksize);
 370                                                         config_set("global", "pthread stack size", optarg);
 371                                                 } else if(strncmp(optarg, debug_flags_string, strlen(debug_flags_string)) == 0) {
 372                                                         optarg += strlen(debug_flags_string);
 373                                                         config_set("global", "debug flags",  optarg);
 374                                                         debug_flags = strtoull(optarg, NULL, 0);
 375                                                 }
 376                                         }
 377                                         break;
 378                                 default: /* ? */
 379                                         help(1);
 380                                         break;
 381                         }
 382                 }
 383         }
 384
 385         if(!config_loaded) load_config(NULL, 0);
 386
 387         // prepare configuration environment variables for the plugins
 388         setenv("NETDATA_CONFIG_DIR" , config_get("global", "config directory"   , CONFIG_DIR) , 1);
 389         setenv("NETDATA_PLUGINS_DIR", config_get("global", "plugins directory"  , PLUGINS_DIR), 1);
 390         setenv("NETDATA_WEB_DIR"    , config_get("global", "web files directory", WEB_DIR)    , 1);
 391         setenv("NETDATA_CACHE_DIR"  , config_get("global", "cache directory"    , CACHE_DIR)  , 1);
 392         setenv("NETDATA_LIB_DIR"    , config_get("global", "lib directory"      , VARLIB_DIR) , 1);
 393         setenv("NETDATA_LOG_DIR"    , config_get("global", "log directory"      , LOG_DIR)    , 1);
 394         setenv("NETDATA_HOST_PREFIX", config_get("global", "host access prefix" , "")         , 1);
 395         setenv("HOME"               , config_get("global", "home directory"     , CACHE_DIR)  , 1);
 396
 397         // avoid extended to stat(/etc/localtime)
 398         // http://stackoverflow.com/questions/4554271/how-to-avoid-excessive-stat-etc-localtime-calls-in-strftime-on-linux
 399         setenv("TZ", ":/etc/localtime", 0);
 400
 401         // cd to /tmp to avoid any plugins writing files at random places
 402         if(chdir("/tmp")) error("netdata: ERROR: Cannot cd to /tmp");
 403
 404         char *input_log_file = NULL;
 405         char *output_log_file = NULL;
 406         char *error_log_file = NULL;
 407         char *access_log_file = NULL;
 408         char *user = NULL;
 409         {
 410                 char buffer[1024];
 411
 412                 // --------------------------------------------------------------------
 413
 414                 sprintf(buffer, "0x%08llx", 0ULL);
 415                 char *flags = config_get("global", "debug flags", buffer);
 416                 setenv("NETDATA_DEBUG_FLAGS", flags, 1);
 417
 418                 debug_flags = strtoull(flags, NULL, 0);
 419                 debug(D_OPTIONS, "Debug flags set to '0x%8llx'.", debug_flags);
 420
 421                 if(debug_flags != 0) {
 422                         struct rlimit rl = { RLIM_INFINITY, RLIM_INFINITY };
 423                         if(setrlimit(RLIMIT_CORE, &rl) != 0)
 424                                 info("Cannot request unlimited core dumps for debugging... Proceeding anyway...");
 425                         prctl(PR_SET_DUMPABLE, 1, 0, 0, 0);
 426                 }
 427
 428                 // --------------------------------------------------------------------
 429
 430 #ifdef MADV_MERGEABLE
 431                 enable_ksm = config_get_boolean("global", "memory deduplication (ksm)", enable_ksm);
 432 #else
 433 #warning "Kernel memory deduplication (KSM) is not available"
 434 #endif
 435
 436                 // --------------------------------------------------------------------
 437
 438
 439                 global_host_prefix = config_get("global", "host access prefix", "");
 440                 setenv("NETDATA_HOST_PREFIX", global_host_prefix, 1);
 441
 442                 // --------------------------------------------------------------------
 443
 444                 output_log_file = config_get("global", "debug log", LOG_DIR "/debug.log");
 445                 if(strcmp(output_log_file, "syslog") == 0) {
 446                         output_log_syslog = 1;
 447                         output_log_file = NULL;
 448                 }
 449                 else if(strcmp(output_log_file, "none") == 0) {
 450                         output_log_syslog = 0;
 451                         output_log_file = NULL;
 452                 }
 453                 else output_log_syslog = 0;
 454
 455                 // --------------------------------------------------------------------
 456
 457                 error_log_file = config_get("global", "error log", LOG_DIR "/error.log");
 458                 if(strcmp(error_log_file, "syslog") == 0) {
 459                         error_log_syslog = 1;
 460                         error_log_file = NULL;
 461                 }
 462                 else if(strcmp(error_log_file, "none") == 0) {
 463                         error_log_syslog = 0;
 464                         error_log_file = NULL;
 465                         // optimization - do not even generate debug log entries
 466                 }
 467                 else error_log_syslog = 0;
 468
 469                 error_log_throttle_period = config_get_number("global", "errors flood protection period", error_log_throttle_period);
 470                 setenv("NETDATA_ERRORS_THROTTLE_PERIOD", config_get("global", "errors flood protection period"    , ""), 1);
 471
 472                 error_log_errors_per_period = config_get_number("global", "errors to trigger flood protection", error_log_errors_per_period);
 473                 setenv("NETDATA_ERRORS_PER_PERIOD"     , config_get("global", "errors to trigger flood protection", ""), 1);
 474
 475                 // --------------------------------------------------------------------
 476
 477                 access_log_file = config_get("global", "access log", LOG_DIR "/access.log");
 478                 if(strcmp(access_log_file, "syslog") == 0) {
 479                         access_log_syslog = 1;
 480                         access_log_file = NULL;
 481                 }
 482                 else if(strcmp(access_log_file, "none") == 0) {
 483                         access_log_syslog = 0;
 484                         access_log_file = NULL;
 485                 }
 486                 else access_log_syslog = 0;
 487
 488                 // --------------------------------------------------------------------
 489
 490                 rrd_memory_mode = rrd_memory_mode_id(config_get("global", "memory mode", rrd_memory_mode_name(rrd_memory_mode)));
 491
 492                 // --------------------------------------------------------------------
 493
 494                 if(gethostname(buffer, HOSTNAME_MAX) == -1)
 495                         error("WARNING: Cannot get machine hostname.");
 496                 hostname = config_get("global", "hostname", buffer);
 497                 debug(D_OPTIONS, "hostname set to '%s'", hostname);
 498
 499                 // --------------------------------------------------------------------
 500
 501                 rrd_default_history_entries = (int) config_get_number("global", "history", RRD_DEFAULT_HISTORY_ENTRIES);
 502                 if(rrd_default_history_entries < 5 || rrd_default_history_entries > RRD_HISTORY_ENTRIES_MAX) {
 503                         info("Invalid save lines %d given. Defaulting to %d.", rrd_default_history_entries, RRD_DEFAULT_HISTORY_ENTRIES);
 504                         rrd_default_history_entries = RRD_DEFAULT_HISTORY_ENTRIES;
 505                 }
 506                 else {
 507                         debug(D_OPTIONS, "save lines set to %d.", rrd_default_history_entries);
 508                 }
 509
 510                 // --------------------------------------------------------------------
 511
 512                 rrd_update_every = (int) config_get_number("global", "update every", UPDATE_EVERY);
 513                 if(rrd_update_every < 1 || rrd_update_every > 600) {
 514                         info("Invalid update timer %d given. Defaulting to %d.", rrd_update_every, UPDATE_EVERY_MAX);
 515                         rrd_update_every = UPDATE_EVERY;
 516                 }
 517                 else debug(D_OPTIONS, "update timer set to %d.", rrd_update_every);
 518
 519                 // let the plugins know the min update_every
 520                 {
 521                         char buf[51];
 522                         snprintfz(buf, 50, "%d", rrd_update_every);
 523                         setenv("NETDATA_UPDATE_EVERY", buf, 1);
 524                 }
 525
 526                 // --------------------------------------------------------------------
 527
 528                 // block signals while initializing threads.
 529                 // this causes the threads to block signals.
 530                 sigset_t sigset;
 531                 sigfillset(&sigset);
 532
 533                 if(pthread_sigmask(SIG_BLOCK, &sigset, NULL) == -1) {
 534                         error("Could not block signals for threads");
 535                 }
 536
 537                 // Catch signals which we want to use to quit savely
 538                 struct sigaction sa;
 539                 sigemptyset(&sa.sa_mask);
 540                 sigaddset(&sa.sa_mask, SIGHUP);
 541                 sigaddset(&sa.sa_mask, SIGINT);
 542                 sigaddset(&sa.sa_mask, SIGTERM);
 543                 sa.sa_handler = sig_handler;
 544                 sa.sa_flags = 0;
 545                 if(sigaction(SIGHUP, &sa, NULL) == -1) {
 546                         error("Failed to change signal handler for SIGHUP");
 547                 }
 548                 if(sigaction(SIGINT, &sa, NULL) == -1) {
 549                         error("Failed to change signal handler for SIGINT");
 550                 }
 551                 if(sigaction(SIGTERM, &sa, NULL) == -1) {
 552                         error("Failed to change signal handler for SIGTERM");
 553                 }
 554                 // Ignore SIGPIPE completely.
 555                 // INFO: If we add signals here we have to unblock them
 556                 // at popen.c when running a external plugin.
 557                 sa.sa_handler = SIG_IGN;
 558                 if(sigaction(SIGPIPE, &sa, NULL) == -1) {
 559                         error("Failed to change signal handler for SIGTERM");
 560                 }
 561
 562                 // --------------------------------------------------------------------
 563
 564                 i = pthread_attr_init(&attr);
 565                 if(i != 0)
 566                         fatal("pthread_attr_init() failed with code %d.", i);
 567
 568                 i = pthread_attr_getstacksize(&attr, &stacksize);
 569                 if(i != 0)
 570                         fatal("pthread_attr_getstacksize() failed with code %d.", i);
 571                 else
 572                         debug(D_OPTIONS, "initial pthread stack size is %zu bytes", stacksize);
 573
 574                 wanted_stacksize = config_get_number("global", "pthread stack size", stacksize);
 575
 576                 // --------------------------------------------------------------------
 577
 578                 for (i = 0; static_threads[i].name != NULL ; i++) {
 579                         struct netdata_static_thread *st = &static_threads[i];
 580
 581                         if(st->config_name) st->enabled = config_get_boolean(st->config_section, st->config_name, st->enabled);
 582                         if(st->enabled && st->init_routine) st->init_routine();
 583                 }
 584
 585                 // --------------------------------------------------------------------
 586
 587                 // get the user we should run
 588                 // IMPORTANT: this is required before web_files_uid()
 589                 user = config_get("global", "run as user"    , (getuid() == 0)?NETDATA_USER:"");
 590
 591                 // IMPORTANT: these have to run once, while single threaded
 592                 web_files_uid(); // IMPORTANT: web_files_uid() before web_files_gid()
 593                 web_files_gid();
 594
 595                 // --------------------------------------------------------------------
 596
 597                 listen_backlog = (int) config_get_number("global", "http port listen backlog", LISTEN_BACKLOG);
 598
 599                 listen_port = (int) config_get_number("global", "port", LISTEN_PORT);
 600                 if(listen_port < 1 || listen_port > 65535) {
 601                         info("Invalid listen port %d given. Defaulting to %d.", listen_port, LISTEN_PORT);
 602                         listen_port = LISTEN_PORT;
 603                 }
 604                 else debug(D_OPTIONS, "Listen port set to %d.", listen_port);
 605
 606                 int ip = 0;
 607                 char *ipv = config_get("global", "ip version", "any");
 608                 if(!strcmp(ipv, "any") || !strcmp(ipv, "both") || !strcmp(ipv, "all")) ip = 0;
 609                 else if(!strcmp(ipv, "ipv4") || !strcmp(ipv, "IPV4") || !strcmp(ipv, "IPv4") || !strcmp(ipv, "4")) ip = 4;
 610                 else if(!strcmp(ipv, "ipv6") || !strcmp(ipv, "IPV6") || !strcmp(ipv, "IPv6") || !strcmp(ipv, "6")) ip = 6;
 611                 else info("Cannot understand ip version '%s'. Assuming 'any'.", ipv);
 612
 613                 if(ip == 0 || ip == 6) listen_fd = create_listen_socket6(config_get("global", "bind socket to IP", "*"), listen_port, listen_backlog);
 614                 if(listen_fd < 0) {
 615                         listen_fd = create_listen_socket4(config_get("global", "bind socket to IP", "*"), listen_port, listen_backlog);
 616                         if(listen_fd >= 0 && ip != 4) info("Managed to open an IPv4 socket on port %d.", listen_port);
 617                 }
 618
 619                 if(listen_fd < 0) fatal("Cannot listen socket.");
 620         }
 621
 622         // never become a problem
 623         if(nice(20) == -1) error("Cannot lower my CPU priority.");
 624
 625         if(become_daemon(dont_fork, 0, user, input_log_file, output_log_file, error_log_file, access_log_file, &access_fd, &stdaccess) == -1)
 626                 fatal("Cannot demonize myself.");
 627
 628 #ifdef NETDATA_INTERNAL_CHECKS
 629         if(debug_flags != 0) {
 630                 struct rlimit rl = { RLIM_INFINITY, RLIM_INFINITY };
 631                 if(setrlimit(RLIMIT_CORE, &rl) != 0)
 632                         info("Cannot request unlimited core dumps for debugging... Proceeding anyway...");
 633                 prctl(PR_SET_DUMPABLE, 1, 0, 0, 0);
 634         }
 635 #endif /* NETDATA_INTERNAL_CHECKS */
 636
 637         if(output_log_syslog || error_log_syslog || access_log_syslog)
 638                 openlog("netdata", LOG_PID, LOG_DAEMON);
 639
 640         info("NetData started on pid %d", getpid());
 641
 642
 643         // ------------------------------------------------------------------------
 644         // get default pthread stack size
 645
 646         if(stacksize < wanted_stacksize) {
 647                 i = pthread_attr_setstacksize(&attr, wanted_stacksize);
 648                 if(i != 0)
 649                         fatal("pthread_attr_setstacksize() to %zu bytes, failed with code %d.", wanted_stacksize, i);
 650                 else
 651                         info("Successfully set pthread stacksize to %zu bytes", wanted_stacksize);
 652         }
 653
 654         // --------------------------------------------------------------------
 655         // initialize the registry
 656
 657         registry_init();
 658
 659         // ------------------------------------------------------------------------
 660         // spawn the threads
 661
 662         for (i = 0; static_threads[i].name != NULL ; i++) {
 663                 struct netdata_static_thread *st = &static_threads[i];
 664
 665                 if(st->enabled) {
 666                         st->thread = malloc(sizeof(pthread_t));
 667                         if(!st->thread)
 668                                 fatal("Cannot allocate pthread_t memory");
 669
 670                         info("Starting thread %s.", st->name);
 671
 672                         if(pthread_create(st->thread, &attr, st->start_routine, NULL))
 673                                 error("failed to create new thread for %s.", st->name);
 674
 675                         else if(pthread_detach(*st->thread))
 676                                 error("Cannot request detach of newly created %s thread.", st->name);
 677                 }
 678                 else info("Not starting thread %s.", st->name);
 679         }
 680
 681         // ------------------------------------------------------------------------
 682         // block signals while initializing threads.
 683         sigset_t sigset;
 684         sigfillset(&sigset);
 685
 686         if(pthread_sigmask(SIG_UNBLOCK, &sigset, NULL) == -1) {
 687                 error("Could not unblock signals for threads");
 688         }
 689
 690         // Handle flags set in the signal handler.
 691         while(1) {
 692                 pause();
 693                 if(netdata_exit) {
 694                         info("Exit main loop of netdata.");
 695                         netdata_cleanup_and_exit(0);
 696                         exit(0);
 697                 }
 698         }
 699 }