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(pidfile[0]) {
  53                 if(unlink(pidfile) != 0)
  54                         error("Cannot unlink pidfile '%s'.", pidfile);
  55         }
  56
  57         info("NetData exiting. Bye bye...");
  58         exit(ret);
  59 }
  60
  61 struct netdata_static_thread {
  62         char *name;
  63
  64         char *config_section;
  65         char *config_name;
  66
  67         int enabled;
  68
  69         pthread_t *thread;
  70
  71         void (*init_routine) (void);
  72         void *(*start_routine) (void *);
  73 } static_threads[] = {
  74 #ifdef INTERNAL_PLUGIN_NFACCT
  75 // nfacct requires root access
  76         // so, we build it as an external plugin with setuid to root
  77         {"nfacct",              "plugins",  "nfacct",     1, NULL, NULL, nfacct_main},
  78 #endif
  79
  80         {"tc",                 "plugins",   "tc",         1, NULL, NULL, tc_main},
  81         {"idlejitter",         "plugins",   "idlejitter", 1, NULL, NULL, cpuidlejitter_main},
  82         {"proc",               "plugins",   "proc",       1, NULL, NULL, proc_main},
  83         {"cgroups",            "plugins",   "cgroups",    1, NULL, NULL, cgroups_main},
  84         {"plugins.d",           NULL,       NULL,         1, NULL, NULL, pluginsd_main},
  85         {"check",               "plugins",  "checks",     0, NULL, NULL, checks_main},
  86         {"web",                 NULL,       NULL,         1, NULL, NULL, socket_listen_main_multi_threaded},
  87         {"web-single-threaded", NULL,       NULL,         0, NULL, NULL, socket_listen_main_single_threaded},
  88         {NULL,                  NULL,       NULL,         0, NULL, NULL, NULL}
  89 };
  90
  91 void web_server_threading_selection(void) {
  92         int threaded = config_get_boolean("global", "multi threaded web server", 1);
  93
  94         int i;
  95         for(i = 0; static_threads[i].name ; i++) {
  96                 if(static_threads[i].start_routine == socket_listen_main_multi_threaded)
  97                         static_threads[i].enabled = threaded?1:0;
  98
  99                 if(static_threads[i].start_routine == socket_listen_main_single_threaded)
 100                         static_threads[i].enabled = threaded?0:1;
 101         }
 102
 103         web_client_timeout = (int) config_get_number("global", "disconnect idle web clients after seconds", DEFAULT_DISCONNECT_IDLE_WEB_CLIENTS_AFTER_SECONDS);
 104
 105 #ifdef NETDATA_WITH_ZLIB
 106         web_enable_gzip = config_get_boolean("global", "enable web responses gzip compression", web_enable_gzip);
 107
 108         char *s = config_get("global", "web compression strategy", "default");
 109         if(!strcmp(s, "default"))
 110                 web_gzip_strategy = Z_DEFAULT_STRATEGY;
 111         else if(!strcmp(s, "filtered"))
 112                 web_gzip_strategy = Z_FILTERED;
 113         else if(!strcmp(s, "huffman only"))
 114                 web_gzip_strategy = Z_HUFFMAN_ONLY;
 115         else if(!strcmp(s, "rle"))
 116                 web_gzip_strategy = Z_RLE;
 117         else if(!strcmp(s, "fixed"))
 118                 web_gzip_strategy = Z_FIXED;
 119         else {
 120                 error("Invalid compression strategy '%s'. Valid strategies are 'default', 'filtered', 'huffman only', 'rle' and 'fixed'. Proceeding with 'default'.");
 121                 web_gzip_strategy = Z_DEFAULT_STRATEGY;
 122         }
 123
 124         web_gzip_level = (int)config_get_number("global", "web compression level", 3);
 125         if(web_gzip_level < 1) {
 126                 error("Invalid compression level %d. Valid levels are 1 (fastest) to 9 (best ratio). Proceeding with level 1 (fastest compression).");
 127                 web_gzip_level = 1;
 128         }
 129         else if(web_gzip_level > 9) {
 130                 error("Invalid compression level %d. Valid levels are 1 (fastest) to 9 (best ratio). Proceeding with level 9 (best compression).");
 131                 web_gzip_level = 9;
 132         }
 133 #endif /* NETDATA_WITH_ZLIB */
 134 }
 135
 136
 137 int killpid(pid_t pid, int sig)
 138 {
 139         int ret = -1;
 140         debug(D_EXIT, "Request to kill pid %d", pid);
 141
 142         errno = 0;
 143         if(kill(pid, 0) == -1) {
 144                 switch(errno) {
 145                         case ESRCH:
 146                                 error("Request to kill pid %d, but it is not running.", pid);
 147                                 break;
 148
 149                         case EPERM:
 150                                 error("Request to kill pid %d, but I do not have enough permissions.", pid);
 151                                 break;
 152
 153                         default:
 154                                 error("Request to kill pid %d, but I received an error.", pid);
 155                                 break;
 156                 }
 157         }
 158         else {
 159                 errno = 0;
 160                 ret = kill(pid, sig);
 161                 if(ret == -1) {
 162                         switch(errno) {
 163                                 case ESRCH:
 164                                         error("Cannot kill pid %d, but it is not running.", pid);
 165                                         break;
 166
 167                                 case EPERM:
 168                                         error("Cannot kill pid %d, but I do not have enough permissions.", pid);
 169                                         break;
 170
 171                                 default:
 172                                         error("Cannot kill pid %d, but I received an error.", pid);
 173                                         break;
 174                         }
 175                 }
 176         }
 177
 178         return ret;
 179 }
 180
 181 void kill_childs()
 182 {
 183         siginfo_t info;
 184
 185         struct web_client *w;
 186         for(w = web_clients; w ; w = w->next) {
 187                 debug(D_EXIT, "Stopping web client %s", w->client_ip);
 188                 pthread_cancel(w->thread);
 189                 pthread_join(w->thread, NULL);
 190         }
 191
 192         int i;
 193         for (i = 0; static_threads[i].name != NULL ; i++) {
 194                 if(static_threads[i].thread) {
 195                         debug(D_EXIT, "Stopping %s thread", static_threads[i].name);
 196                         pthread_cancel(*static_threads[i].thread);
 197                         pthread_join(*static_threads[i].thread, NULL);
 198                         static_threads[i].thread = NULL;
 199                 }
 200         }
 201
 202         if(tc_child_pid) {
 203                 info("Killing tc-qos-helper procees");
 204                 if(killpid(tc_child_pid, SIGTERM) != -1)
 205                         waitid(P_PID, (id_t) tc_child_pid, &info, WEXITED);
 206         }
 207         tc_child_pid = 0;
 208
 209         struct plugind *cd;
 210         for(cd = pluginsd_root ; cd ; cd = cd->next) {
 211                 debug(D_EXIT, "Stopping %s plugin thread", cd->id);
 212                 pthread_cancel(cd->thread);
 213                 pthread_join(cd->thread, NULL);
 214
 215                 if(cd->pid && !cd->obsolete) {
 216                         debug(D_EXIT, "killing %s plugin process", cd->id);
 217                         if(killpid(cd->pid, SIGTERM) != -1)
 218                                 waitid(P_PID, (id_t) cd->pid, &info, WEXITED);
 219                 }
 220         }
 221
 222         // if, for any reason there is any child exited
 223         // catch it here
 224         waitid(P_PID, 0, &info, WEXITED|WNOHANG);
 225
 226         debug(D_EXIT, "All threads/childs stopped.");
 227 }
 228
 229 struct option_def options[] = {
 230         // opt description                                                       arg name                     default value
 231         {'c', "Load alternate configuration file",                               "config_file",                          CONFIG_DIR "/" CONFIG_FILENAME},
 232         {'D', "Disable fork into background",                                    NULL,                                   NULL},
 233         {'h', "Display help message",                                            NULL,                                   NULL},
 234         {'P', "File to save a pid while running",                                "FILE",                                 NULL},
 235         {'i', "The IP address to listen to.",                                    "address",                              "All addresses"},
 236         {'p', "Port to listen. Can be from 1 to 65535.",                         "port_number",                          "19999"},
 237         {'s', "Path to access host /proc and /sys when running in a container.", "PATH",                                 NULL},
 238         {'t', "The frequency in seconds, for data collection. \
 239 Same as 'update every' config file option.",                                 "seconds",                              "1"},
 240         {'u', "System username to run as.",                                      "username",                             "netdata"},
 241         {'v', "Version of the program",                                          NULL,                                   NULL},
 242         {'W', "vendor options.",                                                 "stacksize=<size>|unittest|debug_flag", NULL},
 243 };
 244
 245 void help(int exitcode) {
 246         FILE *stream;
 247         if(exitcode == 0)
 248                 stream = stdout;
 249         else
 250                 stream = stderr;
 251
 252         int num_opts = sizeof(options) / sizeof(struct option_def);
 253         int i;
 254         int max_len_arg = 0;
 255
 256         // Compute maximum argument length
 257         for( i = 0; i < num_opts; i++ ) {
 258                 if(options[i].arg_name) {
 259                         int len_arg = strlen(options[i].arg_name);
 260                         if(len_arg > max_len_arg) max_len_arg = len_arg;
 261                 }
 262         }
 263
 264         fprintf(stream, "SYNOPSIS: netdata [options]\n");
 265         fprintf(stream, "\n");
 266         fprintf(stream, "Options:\n");
 267
 268         // Output options description.
 269         for( i = 0; i < num_opts; i++ ) {
 270                 fprintf(stream, "  -%c %-*s  %s", options[i].val, max_len_arg, options[i].arg_name ? options[i].arg_name : "", options[i].description);
 271                 if(options[i].default_value) {
 272                         fprintf(stream, " Default: %s\n", options[i].default_value);
 273                 } else {
 274                         fprintf(stream, "\n");
 275                 }
 276         }
 277
 278         fflush(stream);
 279         exit(exitcode);
 280 }
 281
 282 // TODO: Remove this function with the nix major release.
 283 void remove_option(int opt_index, int *argc, char **argv) {
 284         int i = opt_index;
 285         // remove the options.
 286         do {
 287                 *argc = *argc - 1;
 288                 for(i = opt_index; i < *argc; i++) {
 289                         argv[i] = argv[i+1];
 290                 }
 291                 i = opt_index;
 292         } while(argv[i][0] != '-' && opt_index >= *argc);
 293 }
 294
 295
 296 int main(int argc, char **argv)
 297 {
 298         int i;
 299         int config_loaded = 0;
 300         int dont_fork = 0;
 301         size_t wanted_stacksize = 0, stacksize = 0;
 302         pthread_attr_t attr;
 303
 304         // global initialization
 305         get_HZ();
 306
 307         // set the name for logging
 308         program_name = "netdata";
 309
 310         // parse command line.
 311
 312         // parse depercated options
 313         // TODO: Remove this block with the next major release.
 314         {
 315                 i = 1;
 316                 while(i < argc) {
 317                         if(strcmp(argv[i], "-pidfile") == 0 && (i+1) < argc) {
 318                                 strncpyz(pidfile, argv[i+1], FILENAME_MAX);
 319                                 fprintf(stderr, "%s: deprecate option -- %s -- please use -P instead.\n", argv[0], argv[i]);
 320                                 remove_option(i, &argc, argv);
 321                         }
 322                         else if(strcmp(argv[i], "-nodaemon") == 0 || strcmp(argv[i], "-nd") == 0) {
 323                                 dont_fork = 1;
 324                                 fprintf(stderr, "%s: deprecate option -- %s -- please use -D instead.\n ", argv[0], argv[i]);
 325                                 remove_option(i, &argc, argv);
 326                         }
 327                         else if(strcmp(argv[i], "-ch") == 0 && (i+1) < argc) {
 328                                 config_set("global", "host access prefix", argv[i+1]);
 329                                 fprintf(stderr, "%s: deprecate option -- %s -- please use -s instead.\n", argv[0], argv[i]);
 330                                 remove_option(i, &argc, argv);
 331                         }
 332                         else if(strcmp(argv[i], "-l") == 0 && (i+1) < argc) {
 333                                 config_set("global", "history", argv[i+1]);
 334                                 fprintf(stderr, "%s: deprecate option -- %s -- This option will be rmoved with V2.*.\n", argv[0], argv[i]);
 335                                 remove_option(i, &argc, argv);
 336                         }
 337                         else i++;
 338                 }
 339         }
 340
 341         // parse options
 342         {
 343                 int num_opts = sizeof(options) / sizeof(struct option_def);
 344                 char optstring[(num_opts * 2) + 1];
 345
 346                 int string_i = 0;
 347                 for( i = 0; i < num_opts; i++ ) {
 348                         optstring[string_i] = options[i].val;
 349                         string_i++;
 350                         if(options[i].arg_name) {
 351                                 optstring[string_i] = ':';
 352                                 string_i++;
 353                         }
 354                 }
 355
 356                 int opt;
 357                 while( (opt = getopt(argc, argv, optstring)) != -1 ) {
 358                         switch(opt) {
 359                                 case 'c':
 360                                         if(load_config(optarg, 1) != 1) {
 361                                                 error("Cannot load configuration file %s.", optarg);
 362                                                 exit(1);
 363                                         }
 364                                         else {
 365                                                 debug(D_OPTIONS, "Configuration loaded from %s.", optarg);
 366                                                 config_loaded = 1;
 367                                         }
 368                                         break;
 369                                 case 'D':
 370                                         dont_fork = 1;
 371                                         break;
 372                                 case 'h':
 373                                         help(0);
 374                                         break;
 375                                 case 'i':
 376                                         config_set("global", "bind socket to IP", optarg);
 377                                         break;
 378                                 case 'P':
 379                                         strncpy(pidfile, optarg, FILENAME_MAX);
 380                                         pidfile[FILENAME_MAX] = '\0';
 381                                         break;
 382                                 case 'p':
 383                                         config_set("global", "port", optarg);
 384                                         break;
 385                                 case 's':
 386                                         config_set("global", "host access prefix", optarg);
 387                                         break;
 388                                 case 't':
 389                                         config_set("global", "update every", optarg);
 390                                         break;
 391                                 case 'u':
 392                                         config_set("global", "run as user", optarg);
 393                                         break;
 394                                 case 'v':
 395                                         // TODO: Outsource version to makefile which can compute version from git.
 396                                         printf("netdata 1.1.0\n");
 397                                         return 0;
 398                                         break;
 399                                 case 'W':
 400                                         {
 401                                                 char* stacksize = "stacksize=";
 402                                                 char* debug_flags_string = "debug_flags=";
 403                                                 if(strcmp(optarg, "unittest") == 0) {
 404                                                         rrd_update_every = 1;
 405                                                         if(run_all_mockup_tests()) exit(1);
 406                                                         if(unit_test_storage()) exit(1);
 407                                                         fprintf(stderr, "\n\nALL TESTS PASSED\n\n");
 408                                                         exit(0);
 409                                                 } else if(strncmp(optarg, stacksize, strlen(stacksize)) == 0) {
 410                                                         optarg += strlen(stacksize);
 411                                                         config_set("global", "pthread stack size", optarg);
 412                                                 } else if(strncmp(optarg, debug_flags_string, strlen(debug_flags_string)) == 0) {
 413                                                         optarg += strlen(debug_flags_string);
 414                                                         config_set("global", "debug flags",  optarg);
 415                                                         debug_flags = strtoull(optarg, NULL, 0);
 416                                                 }
 417                                         }
 418                                         break;
 419                                 default: /* ? */
 420                                         help(1);
 421                                         break;
 422                         }
 423                 }
 424         }
 425
 426         if(!config_loaded) load_config(NULL, 0);
 427
 428         // prepare configuration environment variables for the plugins
 429         setenv("NETDATA_CONFIG_DIR" , config_get("global", "config directory"   , CONFIG_DIR) , 1);
 430         setenv("NETDATA_PLUGINS_DIR", config_get("global", "plugins directory"  , PLUGINS_DIR), 1);
 431         setenv("NETDATA_WEB_DIR"    , config_get("global", "web files directory", WEB_DIR)    , 1);
 432         setenv("NETDATA_CACHE_DIR"  , config_get("global", "cache directory"    , CACHE_DIR)  , 1);
 433         setenv("NETDATA_LIB_DIR"    , config_get("global", "lib directory"      , VARLIB_DIR) , 1);
 434         setenv("NETDATA_LOG_DIR"    , config_get("global", "log directory"      , LOG_DIR)    , 1);
 435         setenv("NETDATA_HOST_PREFIX", config_get("global", "host access prefix" , "")         , 1);
 436         setenv("HOME"               , config_get("global", "home directory"     , CACHE_DIR)  , 1);
 437
 438         // avoid extended to stat(/etc/localtime)
 439         // http://stackoverflow.com/questions/4554271/how-to-avoid-excessive-stat-etc-localtime-calls-in-strftime-on-linux
 440         setenv("TZ", ":/etc/localtime", 0);
 441
 442         // cd to /tmp to avoid any plugins writing files at random places
 443         if(chdir("/tmp")) error("netdata: ERROR: Cannot cd to /tmp");
 444
 445         char *input_log_file = NULL;
 446         char *output_log_file = NULL;
 447         char *error_log_file = NULL;
 448         char *access_log_file = NULL;
 449         char *user = NULL;
 450         {
 451                 char buffer[1024];
 452
 453                 // --------------------------------------------------------------------
 454
 455                 sprintf(buffer, "0x%08llx", 0ULL);
 456                 char *flags = config_get("global", "debug flags", buffer);
 457                 setenv("NETDATA_DEBUG_FLAGS", flags, 1);
 458
 459                 debug_flags = strtoull(flags, NULL, 0);
 460                 debug(D_OPTIONS, "Debug flags set to '0x%8llx'.", debug_flags);
 461
 462                 if(debug_flags != 0) {
 463                         struct rlimit rl = { RLIM_INFINITY, RLIM_INFINITY };
 464                         if(setrlimit(RLIMIT_CORE, &rl) != 0)
 465                                 info("Cannot request unlimited core dumps for debugging... Proceeding anyway...");
 466                         prctl(PR_SET_DUMPABLE, 1, 0, 0, 0);
 467                 }
 468
 469                 // --------------------------------------------------------------------
 470
 471 #ifdef MADV_MERGEABLE
 472                 enable_ksm = config_get_boolean("global", "memory deduplication (ksm)", enable_ksm);
 473 #else
 474 #warning "Kernel memory deduplication (KSM) is not available"
 475 #endif
 476
 477                 // --------------------------------------------------------------------
 478
 479
 480                 global_host_prefix = config_get("global", "host access prefix", "");
 481                 setenv("NETDATA_HOST_PREFIX", global_host_prefix, 1);
 482
 483                 // --------------------------------------------------------------------
 484
 485                 output_log_file = config_get("global", "debug log", LOG_DIR "/debug.log");
 486                 if(strcmp(output_log_file, "syslog") == 0) {
 487                         output_log_syslog = 1;
 488                         output_log_file = NULL;
 489                 }
 490                 else if(strcmp(output_log_file, "none") == 0) {
 491                         output_log_syslog = 0;
 492                         output_log_file = NULL;
 493                 }
 494                 else output_log_syslog = 0;
 495
 496                 // --------------------------------------------------------------------
 497
 498                 error_log_file = config_get("global", "error log", LOG_DIR "/error.log");
 499                 if(strcmp(error_log_file, "syslog") == 0) {
 500                         error_log_syslog = 1;
 501                         error_log_file = NULL;
 502                 }
 503                 else if(strcmp(error_log_file, "none") == 0) {
 504                         error_log_syslog = 0;
 505                         error_log_file = NULL;
 506                         // optimization - do not even generate debug log entries
 507                 }
 508                 else error_log_syslog = 0;
 509
 510                 error_log_throttle_period = config_get_number("global", "errors flood protection period", error_log_throttle_period);
 511                 setenv("NETDATA_ERRORS_THROTTLE_PERIOD", config_get("global", "errors flood protection period"    , ""), 1);
 512
 513                 error_log_errors_per_period = (unsigned long)config_get_number("global", "errors to trigger flood protection", error_log_errors_per_period);
 514                 setenv("NETDATA_ERRORS_PER_PERIOD"     , config_get("global", "errors to trigger flood protection", ""), 1);
 515
 516                 // --------------------------------------------------------------------
 517
 518                 access_log_file = config_get("global", "access log", LOG_DIR "/access.log");
 519                 if(strcmp(access_log_file, "syslog") == 0) {
 520                         access_log_syslog = 1;
 521                         access_log_file = NULL;
 522                 }
 523                 else if(strcmp(access_log_file, "none") == 0) {
 524                         access_log_syslog = 0;
 525                         access_log_file = NULL;
 526                 }
 527                 else access_log_syslog = 0;
 528
 529                 // --------------------------------------------------------------------
 530
 531                 rrd_memory_mode = rrd_memory_mode_id(config_get("global", "memory mode", rrd_memory_mode_name(rrd_memory_mode)));
 532
 533                 // --------------------------------------------------------------------
 534
 535                 if(gethostname(buffer, HOSTNAME_MAX) == -1)
 536                         error("WARNING: Cannot get machine hostname.");
 537                 hostname = config_get("global", "hostname", buffer);
 538                 debug(D_OPTIONS, "hostname set to '%s'", hostname);
 539
 540                 // --------------------------------------------------------------------
 541
 542                 rrd_default_history_entries = (int) config_get_number("global", "history", RRD_DEFAULT_HISTORY_ENTRIES);
 543                 if(rrd_default_history_entries < 5 || rrd_default_history_entries > RRD_HISTORY_ENTRIES_MAX) {
 544                         info("Invalid save lines %d given. Defaulting to %d.", rrd_default_history_entries, RRD_DEFAULT_HISTORY_ENTRIES);
 545                         rrd_default_history_entries = RRD_DEFAULT_HISTORY_ENTRIES;
 546                 }
 547                 else {
 548                         debug(D_OPTIONS, "save lines set to %d.", rrd_default_history_entries);
 549                 }
 550
 551                 // --------------------------------------------------------------------
 552
 553                 rrd_update_every = (int) config_get_number("global", "update every", UPDATE_EVERY);
 554                 if(rrd_update_every < 1 || rrd_update_every > 600) {
 555                         info("Invalid update timer %d given. Defaulting to %d.", rrd_update_every, UPDATE_EVERY_MAX);
 556                         rrd_update_every = UPDATE_EVERY;
 557                 }
 558                 else debug(D_OPTIONS, "update timer set to %d.", rrd_update_every);
 559
 560                 // let the plugins know the min update_every
 561                 {
 562                         char buf[51];
 563                         snprintfz(buf, 50, "%d", rrd_update_every);
 564                         setenv("NETDATA_UPDATE_EVERY", buf, 1);
 565                 }
 566
 567                 // --------------------------------------------------------------------
 568
 569                 // block signals while initializing threads.
 570                 // this causes the threads to block signals.
 571                 sigset_t sigset;
 572                 sigfillset(&sigset);
 573
 574                 if(pthread_sigmask(SIG_BLOCK, &sigset, NULL) == -1) {
 575                         error("Could not block signals for threads");
 576                 }
 577
 578                 // Catch signals which we want to use to quit savely
 579                 struct sigaction sa;
 580                 sigemptyset(&sa.sa_mask);
 581                 sigaddset(&sa.sa_mask, SIGHUP);
 582                 sigaddset(&sa.sa_mask, SIGINT);
 583                 sigaddset(&sa.sa_mask, SIGTERM);
 584                 sa.sa_handler = sig_handler;
 585                 sa.sa_flags = 0;
 586                 if(sigaction(SIGHUP, &sa, NULL) == -1) {
 587                         error("Failed to change signal handler for SIGHUP");
 588                 }
 589                 if(sigaction(SIGINT, &sa, NULL) == -1) {
 590                         error("Failed to change signal handler for SIGINT");
 591                 }
 592                 if(sigaction(SIGTERM, &sa, NULL) == -1) {
 593                         error("Failed to change signal handler for SIGTERM");
 594                 }
 595                 // Ignore SIGPIPE completely.
 596                 // INFO: If we add signals here we have to unblock them
 597                 // at popen.c when running a external plugin.
 598                 sa.sa_handler = SIG_IGN;
 599                 if(sigaction(SIGPIPE, &sa, NULL) == -1) {
 600                         error("Failed to change signal handler for SIGTERM");
 601                 }
 602
 603                 // --------------------------------------------------------------------
 604
 605                 i = pthread_attr_init(&attr);
 606                 if(i != 0)
 607                         fatal("pthread_attr_init() failed with code %d.", i);
 608
 609                 i = pthread_attr_getstacksize(&attr, &stacksize);
 610                 if(i != 0)
 611                         fatal("pthread_attr_getstacksize() failed with code %d.", i);
 612                 else
 613                         debug(D_OPTIONS, "initial pthread stack size is %zu bytes", stacksize);
 614
 615                 wanted_stacksize = config_get_number("global", "pthread stack size", stacksize);
 616
 617                 // --------------------------------------------------------------------
 618
 619                 for (i = 0; static_threads[i].name != NULL ; i++) {
 620                         struct netdata_static_thread *st = &static_threads[i];
 621
 622                         if(st->config_name) st->enabled = config_get_boolean(st->config_section, st->config_name, st->enabled);
 623                         if(st->enabled && st->init_routine) st->init_routine();
 624                 }
 625
 626                 // --------------------------------------------------------------------
 627
 628                 // get the user we should run
 629                 // IMPORTANT: this is required before web_files_uid()
 630                 user = config_get("global", "run as user"    , (getuid() == 0)?NETDATA_USER:"");
 631
 632                 // IMPORTANT: these have to run once, while single threaded
 633                 web_files_uid(); // IMPORTANT: web_files_uid() before web_files_gid()
 634                 web_files_gid();
 635
 636                 // --------------------------------------------------------------------
 637
 638                 listen_fd = create_listen_socket();
 639                 if(listen_fd < 0) fatal("Cannot listen socket.");
 640         }
 641
 642         // never become a problem
 643         if(nice(20) == -1) error("Cannot lower my CPU priority.");
 644
 645         if(become_daemon(dont_fork, 0, user, input_log_file, output_log_file, error_log_file, access_log_file, &access_fd, &stdaccess) == -1)
 646                 fatal("Cannot demonize myself.");
 647
 648 #ifdef NETDATA_INTERNAL_CHECKS
 649         if(debug_flags != 0) {
 650                 struct rlimit rl = { RLIM_INFINITY, RLIM_INFINITY };
 651                 if(setrlimit(RLIMIT_CORE, &rl) != 0)
 652                         info("Cannot request unlimited core dumps for debugging... Proceeding anyway...");
 653                 prctl(PR_SET_DUMPABLE, 1, 0, 0, 0);
 654         }
 655 #endif /* NETDATA_INTERNAL_CHECKS */
 656
 657         if(output_log_syslog || error_log_syslog || access_log_syslog)
 658                 openlog("netdata", LOG_PID, LOG_DAEMON);
 659
 660         info("NetData started on pid %d", getpid());
 661
 662
 663         // ------------------------------------------------------------------------
 664         // get default pthread stack size
 665
 666         if(stacksize < wanted_stacksize) {
 667                 i = pthread_attr_setstacksize(&attr, wanted_stacksize);
 668                 if(i != 0)
 669                         fatal("pthread_attr_setstacksize() to %zu bytes, failed with code %d.", wanted_stacksize, i);
 670                 else
 671                         info("Successfully set pthread stacksize to %zu bytes", wanted_stacksize);
 672         }
 673
 674         // --------------------------------------------------------------------
 675         // initialize the registry
 676
 677         registry_init();
 678
 679         // ------------------------------------------------------------------------
 680         // spawn the threads
 681
 682         web_server_threading_selection();
 683
 684         for (i = 0; static_threads[i].name != NULL ; i++) {
 685                 struct netdata_static_thread *st = &static_threads[i];
 686
 687                 if(st->enabled) {
 688                         st->thread = malloc(sizeof(pthread_t));
 689                         if(!st->thread)
 690                                 fatal("Cannot allocate pthread_t memory");
 691
 692                         info("Starting thread %s.", st->name);
 693
 694                         if(pthread_create(st->thread, &attr, st->start_routine, NULL))
 695                                 error("failed to create new thread for %s.", st->name);
 696
 697                         else if(pthread_detach(*st->thread))
 698                                 error("Cannot request detach of newly created %s thread.", st->name);
 699                 }
 700                 else info("Not starting thread %s.", st->name);
 701         }
 702
 703         // ------------------------------------------------------------------------
 704         // block signals while initializing threads.
 705         sigset_t sigset;
 706         sigfillset(&sigset);
 707
 708         if(pthread_sigmask(SIG_UNBLOCK, &sigset, NULL) == -1) {
 709                 error("Could not unblock signals for threads");
 710         }
 711
 712         // Handle flags set in the signal handler.
 713         while(1) {
 714                 pause();
 715                 if(netdata_exit) {
 716                         info("Exit main loop of netdata.");
 717                         netdata_cleanup_and_exit(0);
 718                         exit(0);
 719                 }
 720         }
 721 }