src/plugins_d.c

   1 #include "common.h"
   2
   3 struct plugind *pluginsd_root = NULL;
   4
   5 #define MAX_WORDS 20
   6
   7 static inline int pluginsd_space(char c) {
   8         switch(c) {
   9         case ' ':
  10         case '\t':
  11         case '\r':
  12         case '\n':
  13         case '=':
  14                 return 1;
  15
  16         default:
  17                 return 0;
  18         }
  19 }
  20
  21 static int pluginsd_split_words(char *str, char **words, int max_words) {
  22         char *s = str, quote = 0;
  23         int i = 0, j;
  24
  25         // skip all white space
  26         while(unlikely(pluginsd_space(*s))) s++;
  27
  28         // check for quote
  29         if(unlikely(*s == '\'' || *s == '"')) {
  30                 quote = *s;     // remember the quote
  31                 s++;            // skip the quote
  32         }
  33
  34         // store the first word
  35         words[i++] = s;
  36
  37         // while we have something
  38         while(likely(*s)) {
  39                 // if it is escape
  40                 if(unlikely(*s == '\\' && s[1])) {
  41                         s += 2;
  42                         continue;
  43                 }
  44
  45                 // if it is quote
  46                 else if(unlikely(*s == quote)) {
  47                         quote = 0;
  48                         *s = ' ';
  49                         continue;
  50                 }
  51
  52                 // if it is a space
  53                 else if(unlikely(quote == 0 && pluginsd_space(*s))) {
  54
  55                         // terminate the word
  56                         *s++ = '\0';
  57
  58                         // skip all white space
  59                         while(likely(pluginsd_space(*s))) s++;
  60
  61                         // check for quote
  62                         if(unlikely(*s == '\'' || *s == '"')) {
  63                                 quote = *s;     // remember the quote
  64                                 s++;            // skip the quote
  65                         }
  66
  67                         // if we reached the end, stop
  68                         if(unlikely(!*s)) break;
  69
  70                         // store the next word
  71                         if(likely(i < max_words)) words[i++] = s;
  72                         else break;
  73                 }
  74
  75                 // anything else
  76                 else s++;
  77         }
  78
  79         // terminate the words
  80         j = i;
  81         while(likely(j < max_words)) words[j++] = NULL;
  82
  83         return i;
  84 }
  85
  86
  87 void *pluginsd_worker_thread(void *arg)
  88 {
  89         struct plugind *cd = (struct plugind *)arg;
  90         char line[PLUGINSD_LINE_MAX + 1];
  91
  92 #ifdef DETACH_PLUGINS_FROM_NETDATA
  93         unsigned long long usec = 0, susec = 0;
  94         struct timeval last = {0, 0} , now = {0, 0};
  95 #endif
  96
  97         char *words[MAX_WORDS] = { NULL };
  98         uint32_t SET_HASH = simple_hash("SET");
  99         uint32_t BEGIN_HASH = simple_hash("BEGIN");
 100         uint32_t END_HASH = simple_hash("END");
 101         uint32_t FLUSH_HASH = simple_hash("FLUSH");
 102         uint32_t CHART_HASH = simple_hash("CHART");
 103         uint32_t DIMENSION_HASH = simple_hash("DIMENSION");
 104         uint32_t DISABLE_HASH = simple_hash("DISABLE");
 105 #ifdef DETACH_PLUGINS_FROM_NETDATA
 106         uint32_t MYPID_HASH = simple_hash("MYPID");
 107         uint32_t STOPPING_WAKE_ME_UP_PLEASE_HASH = simple_hash("STOPPING_WAKE_ME_UP_PLEASE");
 108 #endif
 109
 110         size_t count = 0;
 111
 112         while(likely(1)) {
 113                 if(unlikely(netdata_exit)) break;
 114
 115                 FILE *fp = mypopen(cd->cmd, &cd->pid);
 116                 if(unlikely(!fp)) {
 117                         error("Cannot popen(\"%s\", \"r\").", cd->cmd);
 118                         break;
 119                 }
 120
 121                 info("PLUGINSD: '%s' running on pid %d", cd->fullfilename, cd->pid);
 122
 123                 RRDSET *st = NULL;
 124                 char *s;
 125                 uint32_t hash;
 126
 127                 while(likely(fgets(line, PLUGINSD_LINE_MAX, fp) != NULL)) {
 128                         if(unlikely(netdata_exit)) break;
 129
 130                         line[PLUGINSD_LINE_MAX] = '\0';
 131
 132                         // debug(D_PLUGINSD, "PLUGINSD: %s: %s", cd->filename, line);
 133
 134                         int w = pluginsd_split_words(line, words, MAX_WORDS);
 135                         s = words[0];
 136                         if(unlikely(!s || !*s || !w)) {
 137                                 // debug(D_PLUGINSD, "PLUGINSD: empty line");
 138                                 continue;
 139                         }
 140
 141                         // debug(D_PLUGINSD, "PLUGINSD: words 0='%s' 1='%s' 2='%s' 3='%s' 4='%s' 5='%s' 6='%s' 7='%s' 8='%s' 9='%s'", words[0], words[1], words[2], words[3], words[4], words[5], words[6], words[7], words[8], words[9]);
 142
 143                         hash = simple_hash(s);
 144
 145                         if(likely(hash == SET_HASH && !strcmp(s, "SET"))) {
 146                                 char *dimension = words[1];
 147                                 char *value = words[2];
 148
 149                                 if(unlikely(!dimension || !*dimension)) {
 150                                         error("PLUGINSD: '%s' is requesting a SET on chart '%s', without a dimension. Disabling it.", cd->fullfilename, st->id);
 151                                         cd->enabled = 0;
 152                                         killpid(cd->pid, SIGTERM);
 153                                         break;
 154                                 }
 155
 156                                 if(unlikely(!value || !*value)) value = NULL;
 157
 158                                 if(unlikely(!st)) {
 159                                         error("PLUGINSD: '%s' is requesting a SET on dimension %s with value %s, without a BEGIN. Disabling it.", cd->fullfilename, dimension, value?value:"<nothing>");
 160                                         cd->enabled = 0;
 161                                         killpid(cd->pid, SIGTERM);
 162                                         break;
 163                                 }
 164
 165                                 if(unlikely(st->debug)) debug(D_PLUGINSD, "PLUGINSD: '%s' is setting dimension %s/%s to %s", cd->fullfilename, st->id, dimension, value?value:"<nothing>");
 166
 167                                 if(value) rrddim_set(st, dimension, strtoll(value, NULL, 0));
 168                         }
 169                         else if(likely(hash == BEGIN_HASH && !strcmp(s, "BEGIN"))) {
 170                                 char *id = words[1];
 171                                 char *microseconds_txt = words[2];
 172
 173                                 if(unlikely(!id)) {
 174                                         error("PLUGINSD: '%s' is requesting a BEGIN without a chart id. Disabling it.", cd->fullfilename);
 175                                         cd->enabled = 0;
 176                                         killpid(cd->pid, SIGTERM);
 177                                         break;
 178                                 }
 179
 180                                 st = rrdset_find(id);
 181                                 if(unlikely(!st)) {
 182                                         error("PLUGINSD: '%s' is requesting a BEGIN on chart '%s', which does not exist. Disabling it.", cd->fullfilename, id);
 183                                         cd->enabled = 0;
 184                                         killpid(cd->pid, SIGTERM);
 185                                         break;
 186                                 }
 187
 188                                 if(likely(st->counter_done)) {
 189                                         unsigned long long microseconds = 0;
 190                                         if(microseconds_txt && *microseconds_txt) microseconds = strtoull(microseconds_txt, NULL, 10);
 191                                         if(microseconds) rrdset_next_usec(st, microseconds);
 192                                         else rrdset_next_plugins(st);
 193                                 }
 194                         }
 195                         else if(likely(hash == END_HASH && !strcmp(s, "END"))) {
 196                                 if(unlikely(!st)) {
 197                                         error("PLUGINSD: '%s' is requesting an END, without a BEGIN. Disabling it.", cd->fullfilename);
 198                                         cd->enabled = 0;
 199                                         killpid(cd->pid, SIGTERM);
 200                                         break;
 201                                 }
 202
 203                                 if(unlikely(st->debug)) debug(D_PLUGINSD, "PLUGINSD: '%s' is requesting an END on chart %s", cd->fullfilename, st->id);
 204
 205                                 rrdset_done(st);
 206                                 st = NULL;
 207
 208                                 count++;
 209                         }
 210                         else if(likely(hash == FLUSH_HASH && !strcmp(s, "FLUSH"))) {
 211                                 debug(D_PLUGINSD, "PLUGINSD: '%s' is requesting a FLUSH", cd->fullfilename);
 212                                 st = NULL;
 213                         }
 214                         else if(likely(hash == CHART_HASH && !strcmp(s, "CHART"))) {
 215                                 int noname = 0;
 216                                 st = NULL;
 217
 218                                 if((words[1]) != NULL && (words[2]) != NULL && strcmp(words[1], words[2]) == 0)
 219                                         noname = 1;
 220
 221                                 char *type = words[1];
 222                                 char *id = NULL;
 223                                 if(likely(type)) {
 224                                         id = strchr(type, '.');
 225                                         if(likely(id)) { *id = '\0'; id++; }
 226                                 }
 227                                 char *name = words[2];
 228                                 char *title = words[3];
 229                                 char *units = words[4];
 230                                 char *family = words[5];
 231                                 char *context = words[6];
 232                                 char *chart = words[7];
 233                                 char *priority_s = words[8];
 234                                 char *update_every_s = words[9];
 235
 236                                 if(unlikely(!type || !*type || !id || !*id)) {
 237                                         error("PLUGINSD: '%s' is requesting a CHART, without a type.id. Disabling it.", cd->fullfilename);
 238                                         cd->enabled = 0;
 239                                         killpid(cd->pid, SIGTERM);
 240                                         break;
 241                                 }
 242
 243                                 int priority = 1000;
 244                                 if(likely(priority_s)) priority = atoi(priority_s);
 245
 246                                 int update_every = cd->update_every;
 247                                 if(likely(update_every_s)) update_every = atoi(update_every_s);
 248                                 if(unlikely(!update_every)) update_every = cd->update_every;
 249
 250                                 int chart_type = RRDSET_TYPE_LINE;
 251                                 if(unlikely(chart)) chart_type = rrdset_type_id(chart);
 252
 253                                 if(unlikely(noname || !name || !*name || strcasecmp(name, "NULL") == 0 || strcasecmp(name, "(NULL)") == 0)) name = NULL;
 254                                 if(unlikely(!family || !*family)) family = NULL;
 255                                 if(unlikely(!context || !*context)) context = NULL;
 256
 257                                 st = rrdset_find_bytype(type, id);
 258                                 if(unlikely(!st)) {
 259                                         debug(D_PLUGINSD, "PLUGINSD: Creating chart type='%s', id='%s', name='%s', family='%s', context='%s', chart='%s', priority=%d, update_every=%d"
 260                                                 , type, id
 261                                                 , name?name:""
 262                                                 , family?family:""
 263                                                 , context?context:""
 264                                                 , rrdset_type_name(chart_type)
 265                                                 , priority
 266                                                 , update_every
 267                                                 );
 268
 269                                         st = rrdset_create(type, id, name, family, context, title, units, priority, update_every, chart_type);
 270                                         cd->update_every = update_every;
 271                                 }
 272                                 else debug(D_PLUGINSD, "PLUGINSD: Chart '%s' already exists. Not adding it again.", st->id);
 273                         }
 274                         else if(likely(hash == DIMENSION_HASH && !strcmp(s, "DIMENSION"))) {
 275                                 char *id = words[1];
 276                                 char *name = words[2];
 277                                 char *algorithm = words[3];
 278                                 char *multiplier_s = words[4];
 279                                 char *divisor_s = words[5];
 280                                 char *options = words[6];
 281
 282                                 if(unlikely(!id || !*id)) {
 283                                         error("PLUGINSD: '%s' is requesting a DIMENSION, without an id. Disabling it.", cd->fullfilename);
 284                                         cd->enabled = 0;
 285                                         killpid(cd->pid, SIGTERM);
 286                                         break;
 287                                 }
 288
 289                                 if(unlikely(!st)) {
 290                                         error("PLUGINSD: '%s' is requesting a DIMENSION, without a CHART. Disabling it.", cd->fullfilename);
 291                                         cd->enabled = 0;
 292                                         killpid(cd->pid, SIGTERM);
 293                                         break;
 294                                 }
 295
 296                                 long multiplier = 1;
 297                                 if(multiplier_s && *multiplier_s) multiplier = strtol(multiplier_s, NULL, 0);
 298                                 if(unlikely(!multiplier)) multiplier = 1;
 299
 300                                 long divisor = 1;
 301                                 if(likely(divisor_s && *divisor_s)) divisor = strtol(divisor_s, NULL, 0);
 302                                 if(unlikely(!divisor)) divisor = 1;
 303
 304                                 if(unlikely(!algorithm || !*algorithm)) algorithm = "absolute";
 305
 306                                 if(unlikely(st->debug)) debug(D_PLUGINSD, "PLUGINSD: Creating dimension in chart %s, id='%s', name='%s', algorithm='%s', multiplier=%ld, divisor=%ld, hidden='%s'"
 307                                         , st->id
 308                                         , id
 309                                         , name?name:""
 310                                         , rrddim_algorithm_name(rrddim_algorithm_id(algorithm))
 311                                         , multiplier
 312                                         , divisor
 313                                         , options?options:""
 314                                         );
 315
 316                                 RRDDIM *rd = rrddim_find(st, id);
 317                                 if(unlikely(!rd)) {
 318                                         rd = rrddim_add(st, id, name, multiplier, divisor, rrddim_algorithm_id(algorithm));
 319                                         rd->flags = 0x00000000;
 320                                         if(options && *options) {
 321                                                 if(strstr(options, "hidden") != NULL) rd->flags |= RRDDIM_FLAG_HIDDEN;
 322                                                 if(strstr(options, "noreset") != NULL) rd->flags |= RRDDIM_FLAG_DONT_DETECT_RESETS_OR_OVERFLOWS;
 323                                                 if(strstr(options, "nooverflow") != NULL) rd->flags |= RRDDIM_FLAG_DONT_DETECT_RESETS_OR_OVERFLOWS;
 324                                         }
 325                                 }
 326                                 else if(unlikely(st->debug)) debug(D_PLUGINSD, "PLUGINSD: dimension %s/%s already exists. Not adding it again.", st->id, id);
 327                         }
 328                         else if(unlikely(hash == DISABLE_HASH && !strcmp(s, "DISABLE"))) {
 329                                 error("PLUGINSD: '%s' called DISABLE. Disabling it.", cd->fullfilename);
 330                                 cd->enabled = 0;
 331                                 killpid(cd->pid, SIGTERM);
 332                                 break;
 333                         }
 334 #ifdef DETACH_PLUGINS_FROM_NETDATA
 335                         else if(likely(hash == MYPID_HASH && !strcmp(s, "MYPID"))) {
 336                                 char *pid_s = words[1];
 337                                 pid_t pid = strtod(pid_s, NULL, 0);
 338
 339                                 if(likely(pid)) cd->pid = pid;
 340                                 debug(D_PLUGINSD, "PLUGINSD: %s is on pid %d", cd->id, cd->pid);
 341                         }
 342                         else if(likely(hash == STOPPING_WAKE_ME_UP_PLEASE_HASH && !strcmp(s, "STOPPING_WAKE_ME_UP_PLEASE"))) {
 343                                 error("PLUGINSD: '%s' (pid %d) called STOPPING_WAKE_ME_UP_PLEASE.", cd->fullfilename, cd->pid);
 344
 345                                 gettimeofday(&now, NULL);
 346                                 if(unlikely(!usec && !susec)) {
 347                                         // our first run
 348                                         susec = cd->rrd_update_every * 1000000ULL;
 349                                 }
 350                                 else {
 351                                         // second+ run
 352                                         usec = usecdiff(&now, &last) - susec;
 353                                         error("PLUGINSD: %s last loop took %llu usec (worked for %llu, sleeped for %llu).\n", cd->fullfilename, usec + susec, usec, susec);
 354                                         if(unlikely(usec < (rrd_update_every * 1000000ULL / 2ULL))) susec = (rrd_update_every * 1000000ULL) - usec;
 355                                         else susec = rrd_update_every * 1000000ULL / 2ULL;
 356                                 }
 357
 358                                 error("PLUGINSD: %s sleeping for %llu. Will kill with SIGCONT pid %d to wake it up.\n", cd->fullfilename, susec, cd->pid);
 359                                 usleep(susec);
 360                                 killpid(cd->pid, SIGCONT);
 361                                 bcopy(&now, &last, sizeof(struct timeval));
 362                                 break;
 363                         }
 364 #endif
 365                         else {
 366                                 error("PLUGINSD: '%s' is sending command '%s' which is not known by netdata. Disabling it.", cd->fullfilename, s);
 367                                 cd->enabled = 0;
 368                                 killpid(cd->pid, SIGTERM);
 369                                 break;
 370                         }
 371                 }
 372                 if(likely(count)) {
 373                         cd->successful_collections += count;
 374                         cd->serial_failures = 0;
 375                 }
 376                 else
 377                         cd->serial_failures++;
 378
 379                 info("PLUGINSD: '%s' on pid %d stopped after %zu successful data collections (ENDs).", cd->fullfilename, cd->pid, count);
 380
 381                 // get the return code
 382                 int code = mypclose(fp, cd->pid);
 383
 384                 if(netdata_exit) {
 385                         cd->pid = 0;
 386                         cd->enabled = 0;
 387                         cd->obsolete = 1;
 388                         pthread_exit(NULL);
 389                         return NULL;
 390                 }
 391
 392                 if(code != 0) {
 393                         // the plugin reports failure
 394
 395                         if(likely(!cd->successful_collections)) {
 396                                 // nothing collected - disable it
 397                                 error("PLUGINSD: '%s' exited with error code %d. Disabling it.", cd->fullfilename, code);
 398                                 cd->enabled = 0;
 399                         }
 400                         else {
 401                                 // we have collected something
 402
 403                                 if(likely(cd->serial_failures <= 10)) {
 404                                         error("PLUGINSD: '%s' exited with error code %d, but has given useful output in the past (%zu times). Waiting a bit before starting it again.", cd->fullfilename, code, cd->successful_collections);
 405                                         sleep((unsigned int) (cd->update_every * 10));
 406                                 }
 407                                 else {
 408                                         error("PLUGINSD: '%s' exited with error code %d, but has given useful output in the past (%zu times). We tried %zu times to restart it, but it failed to generate data. Disabling it.", cd->fullfilename, code, cd->successful_collections, cd->serial_failures);
 409                                         cd->enabled = 0;
 410                                 }
 411                         }
 412                 }
 413                 else {
 414                         // the plugin reports success
 415
 416                         if(unlikely(!cd->successful_collections)) {
 417                                 // we have collected nothing so far
 418
 419                                 if(likely(cd->serial_failures <= 10)) {
 420                                         error("PLUGINSD: '%s' (pid %d) does not generate useful output but it reports success (exits with 0). Waiting a bit before starting it again.", cd->fullfilename, cd->pid);
 421                                         sleep((unsigned int) (cd->update_every * 10));
 422                                 }
 423                                 else {
 424                                         error("PLUGINSD: '%s' (pid %d) does not generate useful output, although it reports success (exits with 0), but we have tried %zu times to collect something. Disabling it.", cd->fullfilename, cd->pid, cd->serial_failures);
 425                                         cd->enabled = 0;
 426                                 }
 427                         }
 428                         else
 429                                 sleep((unsigned int) cd->update_every);
 430                 }
 431                 cd->pid = 0;
 432
 433                 if(unlikely(!cd->enabled))
 434                         break;
 435         }
 436
 437         cd->obsolete = 1;
 438         pthread_exit(NULL);
 439         return NULL;
 440 }
 441
 442 void *pluginsd_main(void *ptr)
 443 {
 444         if(ptr) { ; }
 445
 446         info("PLUGINS.D thread created with task id %d", gettid());
 447
 448         if(pthread_setcanceltype(PTHREAD_CANCEL_DEFERRED, NULL) != 0)
 449                 error("Cannot set pthread cancel type to DEFERRED.");
 450
 451         if(pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL) != 0)
 452                 error("Cannot set pthread cancel state to ENABLE.");
 453
 454         char *dir_name = config_get("plugins", "plugins directory", PLUGINS_DIR);
 455         int automatic_run = config_get_boolean("plugins", "enable running new plugins", 1);
 456         int scan_frequency = (int) config_get_number("plugins", "check for new plugins every", 60);
 457         DIR *dir = NULL;
 458         struct dirent *file = NULL;
 459         struct plugind *cd;
 460
 461         // enable the apps plugin by default
 462         // config_get_boolean("plugins", "apps", 1);
 463
 464         if(scan_frequency < 1) scan_frequency = 1;
 465
 466         while(likely(1)) {
 467                 if(unlikely(netdata_exit)) break;
 468
 469                 dir = opendir(dir_name);
 470                 if(unlikely(!dir)) {
 471                         error("Cannot open directory '%s'.", dir_name);
 472                         pthread_exit(NULL);
 473                         return NULL;
 474                 }
 475
 476                 while(likely((file = readdir(dir)))) {
 477                         if(unlikely(netdata_exit)) break;
 478
 479                         debug(D_PLUGINSD, "PLUGINSD: Examining file '%s'", file->d_name);
 480
 481                         if(unlikely(strcmp(file->d_name, ".") == 0 || strcmp(file->d_name, "..") == 0)) continue;
 482
 483                         int len = (int) strlen(file->d_name);
 484                         if(unlikely(len <= (int)PLUGINSD_FILE_SUFFIX_LEN)) continue;
 485                         if(unlikely(strcmp(PLUGINSD_FILE_SUFFIX, &file->d_name[len - (int)PLUGINSD_FILE_SUFFIX_LEN]) != 0)) {
 486                                 debug(D_PLUGINSD, "PLUGINSD: File '%s' does not end in '%s'.", file->d_name, PLUGINSD_FILE_SUFFIX);
 487                                 continue;
 488                         }
 489
 490                         char pluginname[CONFIG_MAX_NAME + 1];
 491                         snprintfz(pluginname, CONFIG_MAX_NAME, "%.*s", (int)(len - PLUGINSD_FILE_SUFFIX_LEN), file->d_name);
 492                         int enabled = config_get_boolean("plugins", pluginname, automatic_run);
 493
 494                         if(unlikely(!enabled)) {
 495                                 debug(D_PLUGINSD, "PLUGINSD: plugin '%s' is not enabled", file->d_name);
 496                                 continue;
 497                         }
 498
 499                         // check if it runs already
 500                         for(cd = pluginsd_root ; likely(cd) ; cd = cd->next) {
 501                                 if(unlikely(strcmp(cd->filename, file->d_name) == 0)) break;
 502                         }
 503                         if(likely(cd && !cd->obsolete)) {
 504                                 debug(D_PLUGINSD, "PLUGINSD: plugin '%s' is already running", cd->filename);
 505                                 continue;
 506                         }
 507
 508                         // it is not running
 509                         // allocate a new one, or use the obsolete one
 510                         if(unlikely(!cd)) {
 511                                 cd = calloc(sizeof(struct plugind), 1);
 512                                 if(unlikely(!cd)) fatal("Cannot allocate memory for plugin.");
 513
 514                                 snprintfz(cd->id, CONFIG_MAX_NAME, "plugin:%s", pluginname);
 515
 516                                 strncpyz(cd->filename, file->d_name, FILENAME_MAX);
 517                                 snprintfz(cd->fullfilename, FILENAME_MAX, "%s/%s", dir_name, cd->filename);
 518
 519                                 cd->enabled = enabled;
 520                                 cd->update_every = (int) config_get_number(cd->id, "update every", rrd_update_every);
 521                                 cd->started_t = time(NULL);
 522
 523                                 char *def = "";
 524                                 snprintfz(cd->cmd, PLUGINSD_CMD_MAX, "exec %s %d %s", cd->fullfilename, cd->update_every, config_get(cd->id, "command options", def));
 525
 526                                 // link it
 527                                 if(likely(pluginsd_root)) cd->next = pluginsd_root;
 528                                 pluginsd_root = cd;
 529                         }
 530                         cd->obsolete = 0;
 531
 532                         if(unlikely(!cd->enabled)) continue;
 533
 534                         // spawn a new thread for it
 535                         if(unlikely(pthread_create(&cd->thread, NULL, pluginsd_worker_thread, cd) != 0)) {
 536                                 error("PLUGINSD: failed to create new thread for plugin '%s'.", cd->filename);
 537                                 cd->obsolete = 1;
 538                         }
 539                         else if(unlikely(pthread_detach(cd->thread) != 0))
 540                                 error("PLUGINSD: Cannot request detach of newly created thread for plugin '%s'.", cd->filename);
 541                 }
 542
 543                 closedir(dir);
 544                 sleep((unsigned int) scan_frequency);
 545         }
 546
 547         pthread_exit(NULL);
 548         return NULL;
 549 }