1 /**
2 * collectd - src/collectd.c
3 * Copyright (C) 2005-2007 Florian octo Forster
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation; only version 2 of the License is applicable.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
17 *
18 * Authors:
19 * Florian octo Forster <octo at verplant.org>
20 * Alvaro Barcellos <alvaro.barcellos at gmail.com>
21 **/
23 #include "collectd.h"
24 #include "common.h"
26 #include <sys/types.h>
27 #include <sys/socket.h>
28 #include <netdb.h>
30 #include <pthread.h>
32 #include "plugin.h"
33 #include "configfile.h"
35 #if HAVE_STATGRAB_H
36 # include <statgrab.h>
37 #endif
39 /*
40 * Global variables
41 */
42 char hostname_g[DATA_MAX_NAME_LEN];
43 cdtime_t interval_g;
44 int timeout_g;
45 #if HAVE_LIBKSTAT
46 kstat_ctl_t *kc;
47 #endif /* HAVE_LIBKSTAT */
49 static int loop = 0;
51 static void *do_flush (void __attribute__((unused)) *arg)
52 {
53 INFO ("Flushing all data.");
54 plugin_flush (/* plugin = */ NULL,
55 /* timeout = */ 0,
56 /* ident = */ NULL);
57 INFO ("Finished flushing all data.");
58 pthread_exit (NULL);
59 return NULL;
60 }
62 static void sig_int_handler (int __attribute__((unused)) signal)
63 {
64 loop++;
65 }
67 static void sig_term_handler (int __attribute__((unused)) signal)
68 {
69 loop++;
70 }
72 static void sig_usr1_handler (int __attribute__((unused)) signal)
73 {
74 pthread_t thread;
75 pthread_attr_t attr;
77 /* flushing the data might take a while,
78 * so it should be done asynchronously */
79 pthread_attr_init (&attr);
80 pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
81 pthread_create (&thread, &attr, do_flush, NULL);
82 pthread_attr_destroy (&attr);
83 }
85 static int init_hostname (void)
86 {
87 const char *str;
89 struct addrinfo ai_hints;
90 struct addrinfo *ai_list;
91 struct addrinfo *ai_ptr;
92 int status;
94 str = global_option_get ("Hostname");
95 if (str != NULL)
96 {
97 sstrncpy (hostname_g, str, sizeof (hostname_g));
98 return (0);
99 }
101 if (gethostname (hostname_g, sizeof (hostname_g)) != 0)
102 {
103 fprintf (stderr, "`gethostname' failed and no "
104 "hostname was configured.\n");
105 return (-1);
106 }
108 str = global_option_get ("FQDNLookup");
109 if (IS_FALSE (str))
110 return (0);
112 memset (&ai_hints, '\0', sizeof (ai_hints));
113 ai_hints.ai_flags = AI_CANONNAME;
115 status = getaddrinfo (hostname_g, NULL, &ai_hints, &ai_list);
116 if (status != 0)
117 {
118 ERROR ("Looking up \"%s\" failed. You have set the "
119 "\"FQDNLookup\" option, but I cannot resolve "
120 "my hostname to a fully qualified domain "
121 "name. Please fix you network "
122 "configuration.", hostname_g);
123 return (-1);
124 }
126 for (ai_ptr = ai_list; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next)
127 {
128 if (ai_ptr->ai_canonname == NULL)
129 continue;
131 sstrncpy (hostname_g, ai_ptr->ai_canonname, sizeof (hostname_g));
132 break;
133 }
135 freeaddrinfo (ai_list);
136 return (0);
137 } /* int init_hostname */
139 static int init_global_variables (void)
140 {
141 const char *str;
143 str = global_option_get ("Interval");
144 if (str == NULL)
145 {
146 interval_g = TIME_T_TO_CDTIME_T (10);
147 }
148 else
149 {
150 double tmp;
152 tmp = atof (str);
153 if (tmp <= 0.0)
154 {
155 fprintf (stderr, "Cannot set the interval to a "
156 "correct value.\n"
157 "Please check your settings.\n");
158 return (-1);
159 }
161 interval_g = DOUBLE_TO_CDTIME_T (tmp);
162 }
163 DEBUG ("interval_g = %.3f;", CDTIME_T_TO_DOUBLE (interval_g));
165 str = global_option_get ("Timeout");
166 if (str == NULL)
167 str = "2";
168 timeout_g = atoi (str);
169 if (timeout_g <= 1)
170 {
171 fprintf (stderr, "Cannot set the timeout to a correct value.\n"
172 "Please check your settings.\n");
173 return (-1);
174 }
175 DEBUG ("timeout_g = %i;", timeout_g);
177 if (init_hostname () != 0)
178 return (-1);
179 DEBUG ("hostname_g = %s;", hostname_g);
181 return (0);
182 } /* int init_global_variables */
184 static int change_basedir (const char *orig_dir)
185 {
186 char *dir;
187 size_t dirlen;
188 int status;
190 dir = strdup (orig_dir);
191 if (dir == NULL)
192 {
193 char errbuf[1024];
194 ERROR ("strdup failed: %s",
195 sstrerror (errno, errbuf, sizeof (errbuf)));
196 return (-1);
197 }
199 dirlen = strlen (dir);
200 while ((dirlen > 0) && (dir[dirlen - 1] == '/'))
201 dir[--dirlen] = '\0';
203 if (dirlen <= 0)
204 return (-1);
206 status = chdir (dir);
207 if (status == 0)
208 {
209 free (dir);
210 return (0);
211 }
212 else if (errno != ENOENT)
213 {
214 char errbuf[1024];
215 ERROR ("change_basedir: chdir (%s): %s", dir,
216 sstrerror (errno, errbuf, sizeof (errbuf)));
217 free (dir);
218 return (-1);
219 }
221 status = mkdir (dir, S_IRWXU | S_IRWXG | S_IRWXO);
222 if (status != 0)
223 {
224 char errbuf[1024];
225 ERROR ("change_basedir: mkdir (%s): %s", dir,
226 sstrerror (errno, errbuf, sizeof (errbuf)));
227 free (dir);
228 return (-1);
229 }
231 status = chdir (dir);
232 if (status != 0)
233 {
234 char errbuf[1024];
235 ERROR ("change_basedir: chdir (%s): %s", dir,
236 sstrerror (errno, errbuf, sizeof (errbuf)));
237 free (dir);
238 return (-1);
239 }
241 free (dir);
242 return (0);
243 } /* static int change_basedir (char *dir) */
245 #if HAVE_LIBKSTAT
246 static void update_kstat (void)
247 {
248 if (kc == NULL)
249 {
250 if ((kc = kstat_open ()) == NULL)
251 ERROR ("Unable to open kstat control structure");
252 }
253 else
254 {
255 kid_t kid;
256 kid = kstat_chain_update (kc);
257 if (kid > 0)
258 {
259 INFO ("kstat chain has been updated");
260 plugin_init_all ();
261 }
262 else if (kid < 0)
263 ERROR ("kstat chain update failed");
264 /* else: everything works as expected */
265 }
267 return;
268 } /* static void update_kstat (void) */
269 #endif /* HAVE_LIBKSTAT */
271 /* TODO
272 * Remove all settings but `-f' and `-C'
273 */
274 static void exit_usage (int status)
275 {
276 printf ("Usage: "PACKAGE" [OPTIONS]\n\n"
278 "Available options:\n"
279 " General:\n"
280 " -C <file> Configuration file.\n"
281 " Default: "CONFIGFILE"\n"
282 " -t Test config and exit.\n"
283 " -T Test plugin read and exit.\n"
284 " -P <file> PID-file.\n"
285 " Default: "PIDFILE"\n"
286 #if COLLECT_DAEMON
287 " -f Don't fork to the background.\n"
288 #endif
289 " -h Display help (this message)\n"
290 "\nBuiltin defaults:\n"
291 " Config file "CONFIGFILE"\n"
292 " PID file "PIDFILE"\n"
293 " Plugin directory "PLUGINDIR"\n"
294 " Data directory "PKGLOCALSTATEDIR"\n"
295 "\n"PACKAGE" "VERSION", http://collectd.org/\n"
296 "by Florian octo Forster <octo@verplant.org>\n"
297 "for contributions see `AUTHORS'\n");
298 exit (status);
299 } /* static void exit_usage (int status) */
301 static int do_init (void)
302 {
303 #if HAVE_LIBKSTAT
304 kc = NULL;
305 update_kstat ();
306 #endif
308 #if HAVE_LIBSTATGRAB
309 if (sg_init ())
310 {
311 ERROR ("sg_init: %s", sg_str_error (sg_get_error ()));
312 return (-1);
313 }
315 if (sg_drop_privileges ())
316 {
317 ERROR ("sg_drop_privileges: %s", sg_str_error (sg_get_error ()));
318 return (-1);
319 }
320 #endif
322 plugin_init_all ();
324 return (0);
325 } /* int do_init () */
328 static int do_loop (void)
329 {
330 cdtime_t wait_until;
332 wait_until = cdtime () + interval_g;
334 while (loop == 0)
335 {
336 struct timespec ts_wait = { 0, 0 };
337 cdtime_t now;
339 #if HAVE_LIBKSTAT
340 update_kstat ();
341 #endif
343 /* Issue all plugins */
344 plugin_read_all ();
346 now = cdtime ();
347 if (now >= wait_until)
348 {
349 WARNING ("Not sleeping because the next interval is "
350 "%.3f seconds in the past!",
351 CDTIME_T_TO_DOUBLE (now - wait_until));
352 wait_until = now + interval_g;
353 continue;
354 }
356 CDTIME_T_TO_TIMESPEC (wait_until - now, &ts_wait);
357 wait_until = wait_until + interval_g;
359 while ((loop == 0) && (nanosleep (&ts_wait, &ts_wait) != 0))
360 {
361 if (errno != EINTR)
362 {
363 char errbuf[1024];
364 ERROR ("nanosleep failed: %s",
365 sstrerror (errno, errbuf,
366 sizeof (errbuf)));
367 return (-1);
368 }
369 }
370 } /* while (loop == 0) */
372 return (0);
373 } /* int do_loop */
375 static int do_shutdown (void)
376 {
377 plugin_shutdown_all ();
378 return (0);
379 } /* int do_shutdown */
381 #if COLLECT_DAEMON
382 static int pidfile_create (void)
383 {
384 FILE *fh;
385 const char *file = global_option_get ("PIDFile");
387 if ((fh = fopen (file, "w")) == NULL)
388 {
389 char errbuf[1024];
390 ERROR ("fopen (%s): %s", file,
391 sstrerror (errno, errbuf, sizeof (errbuf)));
392 return (1);
393 }
395 fprintf (fh, "%i\n", (int) getpid ());
396 fclose(fh);
398 return (0);
399 } /* static int pidfile_create (const char *file) */
401 static int pidfile_remove (void)
402 {
403 const char *file = global_option_get ("PIDFile");
405 DEBUG ("unlink (%s)", (file != NULL) ? file : "<null>");
406 return (unlink (file));
407 } /* static int pidfile_remove (const char *file) */
408 #endif /* COLLECT_DAEMON */
410 int main (int argc, char **argv)
411 {
412 struct sigaction sig_int_action;
413 struct sigaction sig_term_action;
414 struct sigaction sig_usr1_action;
415 struct sigaction sig_pipe_action;
416 char *configfile = CONFIGFILE;
417 int test_config = 0;
418 int test_readall = 0;
419 const char *basedir;
420 #if COLLECT_DAEMON
421 struct sigaction sig_chld_action;
422 pid_t pid;
423 int daemonize = 1;
424 #endif
425 int exit_status = 0;
427 /* read options */
428 while (1)
429 {
430 int c;
432 c = getopt (argc, argv, "htTC:"
433 #if COLLECT_DAEMON
434 "fP:"
435 #endif
436 );
438 if (c == -1)
439 break;
441 switch (c)
442 {
443 case 'C':
444 configfile = optarg;
445 break;
446 case 't':
447 test_config = 1;
448 break;
449 case 'T':
450 test_readall = 1;
451 global_option_set ("ReadThreads", "-1");
452 #if COLLECT_DAEMON
453 daemonize = 0;
454 #endif /* COLLECT_DAEMON */
455 break;
456 #if COLLECT_DAEMON
457 case 'P':
458 global_option_set ("PIDFile", optarg);
459 break;
460 case 'f':
461 daemonize = 0;
462 break;
463 #endif /* COLLECT_DAEMON */
464 case 'h':
465 exit_usage (0);
466 break;
467 default:
468 exit_usage (1);
469 } /* switch (c) */
470 } /* while (1) */
472 if (optind < argc)
473 exit_usage (1);
475 /*
476 * Read options from the config file, the environment and the command
477 * line (in that order, with later options overwriting previous ones in
478 * general).
479 * Also, this will automatically load modules.
480 */
481 if (cf_read (configfile))
482 {
483 fprintf (stderr, "Error: Reading the config file failed!\n"
484 "Read the syslog for details.\n");
485 return (1);
486 }
488 /*
489 * Change directory. We do this _after_ reading the config and loading
490 * modules to relative paths work as expected.
491 */
492 if ((basedir = global_option_get ("BaseDir")) == NULL)
493 {
494 fprintf (stderr, "Don't have a basedir to use. This should not happen. Ever.");
495 return (1);
496 }
497 else if (change_basedir (basedir))
498 {
499 fprintf (stderr, "Error: Unable to change to directory `%s'.\n", basedir);
500 return (1);
501 }
503 /*
504 * Set global variables or, if that failes, exit. We cannot run with
505 * them being uninitialized. If nothing is configured, then defaults
506 * are being used. So this means that the user has actually done
507 * something wrong.
508 */
509 if (init_global_variables () != 0)
510 return (1);
512 if (test_config)
513 return (0);
515 #if COLLECT_DAEMON
516 /*
517 * fork off child
518 */
519 memset (&sig_chld_action, '\0', sizeof (sig_chld_action));
520 sig_chld_action.sa_handler = SIG_IGN;
521 sigaction (SIGCHLD, &sig_chld_action, NULL);
523 if (daemonize)
524 {
525 if ((pid = fork ()) == -1)
526 {
527 /* error */
528 char errbuf[1024];
529 fprintf (stderr, "fork: %s",
530 sstrerror (errno, errbuf,
531 sizeof (errbuf)));
532 return (1);
533 }
534 else if (pid != 0)
535 {
536 /* parent */
537 /* printf ("Running (PID %i)\n", pid); */
538 return (0);
539 }
541 /* Detach from session */
542 setsid ();
544 /* Write pidfile */
545 if (pidfile_create ())
546 exit (2);
548 /* close standard descriptors */
549 close (2);
550 close (1);
551 close (0);
553 if (open ("/dev/null", O_RDWR) != 0)
554 {
555 ERROR ("Error: Could not connect `STDIN' to `/dev/null'");
556 return (1);
557 }
558 if (dup (0) != 1)
559 {
560 ERROR ("Error: Could not connect `STDOUT' to `/dev/null'");
561 return (1);
562 }
563 if (dup (0) != 2)
564 {
565 ERROR ("Error: Could not connect `STDERR' to `/dev/null'");
566 return (1);
567 }
568 } /* if (daemonize) */
569 #endif /* COLLECT_DAEMON */
571 memset (&sig_pipe_action, '\0', sizeof (sig_pipe_action));
572 sig_pipe_action.sa_handler = SIG_IGN;
573 sigaction (SIGPIPE, &sig_pipe_action, NULL);
575 /*
576 * install signal handlers
577 */
578 memset (&sig_int_action, '\0', sizeof (sig_int_action));
579 sig_int_action.sa_handler = sig_int_handler;
580 if (0 != sigaction (SIGINT, &sig_int_action, NULL)) {
581 char errbuf[1024];
582 ERROR ("Error: Failed to install a signal handler for signal INT: %s",
583 sstrerror (errno, errbuf, sizeof (errbuf)));
584 return (1);
585 }
587 memset (&sig_term_action, '\0', sizeof (sig_term_action));
588 sig_term_action.sa_handler = sig_term_handler;
589 if (0 != sigaction (SIGTERM, &sig_term_action, NULL)) {
590 char errbuf[1024];
591 ERROR ("Error: Failed to install a signal handler for signal TERM: %s",
592 sstrerror (errno, errbuf, sizeof (errbuf)));
593 return (1);
594 }
596 memset (&sig_usr1_action, '\0', sizeof (sig_usr1_action));
597 sig_usr1_action.sa_handler = sig_usr1_handler;
598 if (0 != sigaction (SIGUSR1, &sig_usr1_action, NULL)) {
599 char errbuf[1024];
600 ERROR ("Error: Failed to install a signal handler for signal USR1: %s",
601 sstrerror (errno, errbuf, sizeof (errbuf)));
602 return (1);
603 }
605 /*
606 * run the actual loops
607 */
608 do_init ();
610 if (test_readall)
611 {
612 if (plugin_read_all_once () != 0)
613 exit_status = 1;
614 }
615 else
616 {
617 INFO ("Initialization complete, entering read-loop.");
618 do_loop ();
619 }
621 /* close syslog */
622 INFO ("Exiting normally.");
624 do_shutdown ();
626 #if COLLECT_DAEMON
627 if (daemonize)
628 pidfile_remove ();
629 #endif /* COLLECT_DAEMON */
631 return (exit_status);
632 } /* int main */