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 int 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 (NULL, -1, NULL);
55 INFO ("Finished flushing all data.");
56 pthread_exit (NULL);
57 return NULL;
58 }
60 static void sig_int_handler (int __attribute__((unused)) signal)
61 {
62 loop++;
63 }
65 static void sig_term_handler (int __attribute__((unused)) signal)
66 {
67 loop++;
68 }
70 static void sig_usr1_handler (int __attribute__((unused)) signal)
71 {
72 pthread_t thread;
73 pthread_attr_t attr;
75 /* flushing the data might take a while,
76 * so it should be done asynchronously */
77 pthread_attr_init (&attr);
78 pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
79 pthread_create (&thread, &attr, do_flush, NULL);
80 pthread_attr_destroy (&attr);
81 }
83 static int init_hostname (void)
84 {
85 const char *str;
87 struct addrinfo ai_hints;
88 struct addrinfo *ai_list;
89 struct addrinfo *ai_ptr;
90 int status;
92 str = global_option_get ("Hostname");
93 if (str != NULL)
94 {
95 sstrncpy (hostname_g, str, sizeof (hostname_g));
96 return (0);
97 }
99 if (gethostname (hostname_g, sizeof (hostname_g)) != 0)
100 {
101 fprintf (stderr, "`gethostname' failed and no "
102 "hostname was configured.\n");
103 return (-1);
104 }
106 str = global_option_get ("FQDNLookup");
107 if (IS_FALSE (str))
108 return (0);
110 memset (&ai_hints, '\0', sizeof (ai_hints));
111 ai_hints.ai_flags = AI_CANONNAME;
113 status = getaddrinfo (hostname_g, NULL, &ai_hints, &ai_list);
114 if (status != 0)
115 {
116 ERROR ("Looking up \"%s\" failed. You have set the "
117 "\"FQDNLookup\" option, but I cannot resolve "
118 "my hostname to a fully qualified domain "
119 "name. Please fix you network "
120 "configuration.", hostname_g);
121 return (-1);
122 }
124 for (ai_ptr = ai_list; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next)
125 {
126 if (ai_ptr->ai_canonname == NULL)
127 continue;
129 sstrncpy (hostname_g, ai_ptr->ai_canonname, sizeof (hostname_g));
130 break;
131 }
133 freeaddrinfo (ai_list);
134 return (0);
135 } /* int init_hostname */
137 static int init_global_variables (void)
138 {
139 const char *str;
141 str = global_option_get ("Interval");
142 if (str == NULL)
143 str = "10";
144 interval_g = atoi (str);
145 if (interval_g <= 0)
146 {
147 fprintf (stderr, "Cannot set the interval to a correct value.\n"
148 "Please check your settings.\n");
149 return (-1);
150 }
151 DEBUG ("interval_g = %i;", interval_g);
153 str = global_option_get ("Timeout");
154 if (str == NULL)
155 str = "2";
156 timeout_g = atoi (str);
157 if (timeout_g <= 1)
158 {
159 fprintf (stderr, "Cannot set the timeout to a correct value.\n"
160 "Please check your settings.\n");
161 return (-1);
162 }
163 DEBUG ("timeout_g = %i;", timeout_g);
165 if (init_hostname () != 0)
166 return (-1);
167 DEBUG ("hostname_g = %s;", hostname_g);
169 return (0);
170 } /* int init_global_variables */
172 static int change_basedir (const char *orig_dir)
173 {
174 char *dir;
175 size_t dirlen;
176 int status;
178 dir = strdup (orig_dir);
179 if (dir == NULL)
180 {
181 char errbuf[1024];
182 ERROR ("strdup failed: %s",
183 sstrerror (errno, errbuf, sizeof (errbuf)));
184 return (-1);
185 }
187 dirlen = strlen (dir);
188 while ((dirlen > 0) && (dir[dirlen - 1] == '/'))
189 dir[--dirlen] = '\0';
191 if (dirlen <= 0)
192 return (-1);
194 status = chdir (dir);
195 if (status == 0)
196 {
197 free (dir);
198 return (0);
199 }
200 else if (errno != ENOENT)
201 {
202 char errbuf[1024];
203 ERROR ("change_basedir: chdir (%s): %s", dir,
204 sstrerror (errno, errbuf, sizeof (errbuf)));
205 free (dir);
206 return (-1);
207 }
209 status = mkdir (dir, S_IRWXU | S_IRWXG | S_IRWXO);
210 if (status != 0)
211 {
212 char errbuf[1024];
213 ERROR ("change_basedir: mkdir (%s): %s", dir,
214 sstrerror (errno, errbuf, sizeof (errbuf)));
215 free (dir);
216 return (-1);
217 }
219 status = chdir (dir);
220 if (status != 0)
221 {
222 char errbuf[1024];
223 ERROR ("change_basedir: chdir (%s): %s", dir,
224 sstrerror (errno, errbuf, sizeof (errbuf)));
225 free (dir);
226 return (-1);
227 }
229 free (dir);
230 return (0);
231 } /* static int change_basedir (char *dir) */
233 #if HAVE_LIBKSTAT
234 static void update_kstat (void)
235 {
236 if (kc == NULL)
237 {
238 if ((kc = kstat_open ()) == NULL)
239 ERROR ("Unable to open kstat control structure");
240 }
241 else
242 {
243 kid_t kid;
244 kid = kstat_chain_update (kc);
245 if (kid > 0)
246 {
247 INFO ("kstat chain has been updated");
248 plugin_init_all ();
249 }
250 else if (kid < 0)
251 ERROR ("kstat chain update failed");
252 /* else: everything works as expected */
253 }
255 return;
256 } /* static void update_kstat (void) */
257 #endif /* HAVE_LIBKSTAT */
259 /* TODO
260 * Remove all settings but `-f' and `-C'
261 */
262 static void exit_usage (int status)
263 {
264 printf ("Usage: "PACKAGE" [OPTIONS]\n\n"
266 "Available options:\n"
267 " General:\n"
268 " -C <file> Configuration file.\n"
269 " Default: "CONFIGFILE"\n"
270 " -t Test config and exit.\n"
271 " -T Test plugin read and exit.\n"
272 " -P <file> PID-file.\n"
273 " Default: "PIDFILE"\n"
274 #if COLLECT_DAEMON
275 " -f Don't fork to the background.\n"
276 #endif
277 " -h Display help (this message)\n"
278 "\nBuiltin defaults:\n"
279 " Config file "CONFIGFILE"\n"
280 " PID file "PIDFILE"\n"
281 " Plugin directory "PLUGINDIR"\n"
282 " Data directory "PKGLOCALSTATEDIR"\n"
283 "\n"PACKAGE" "VERSION", http://collectd.org/\n"
284 "by Florian octo Forster <octo@verplant.org>\n"
285 "for contributions see `AUTHORS'\n");
286 exit (status);
287 } /* static void exit_usage (int status) */
289 static int do_init (void)
290 {
291 #if HAVE_LIBKSTAT
292 kc = NULL;
293 update_kstat ();
294 #endif
296 #if HAVE_LIBSTATGRAB
297 if (sg_init ())
298 {
299 ERROR ("sg_init: %s", sg_str_error (sg_get_error ()));
300 return (-1);
301 }
303 if (sg_drop_privileges ())
304 {
305 ERROR ("sg_drop_privileges: %s", sg_str_error (sg_get_error ()));
306 return (-1);
307 }
308 #endif
310 plugin_init_all ();
312 return (0);
313 } /* int do_init () */
316 static int do_loop (void)
317 {
318 struct timeval tv_now;
319 struct timeval tv_next;
320 struct timeval tv_wait;
321 struct timespec ts_wait;
323 while (loop == 0)
324 {
325 if (gettimeofday (&tv_next, NULL) < 0)
326 {
327 char errbuf[1024];
328 ERROR ("gettimeofday failed: %s",
329 sstrerror (errno, errbuf,
330 sizeof (errbuf)));
331 return (-1);
332 }
333 tv_next.tv_sec += interval_g;
335 #if HAVE_LIBKSTAT
336 update_kstat ();
337 #endif
339 /* Issue all plugins */
340 plugin_read_all ();
342 if (gettimeofday (&tv_now, NULL) < 0)
343 {
344 char errbuf[1024];
345 ERROR ("gettimeofday failed: %s",
346 sstrerror (errno, errbuf,
347 sizeof (errbuf)));
348 return (-1);
349 }
351 if (timeval_cmp (tv_next, tv_now, &tv_wait) <= 0)
352 {
353 WARNING ("Not sleeping because the next interval is "
354 "%i.%06i seconds in the past!",
355 (int) tv_wait.tv_sec, (int) tv_wait.tv_usec);
356 continue;
357 }
359 ts_wait.tv_sec = tv_wait.tv_sec;
360 ts_wait.tv_nsec = (long) (1000 * tv_wait.tv_usec);
362 while ((loop == 0) && (nanosleep (&ts_wait, &ts_wait) == -1))
363 {
364 if (errno != EINTR)
365 {
366 char errbuf[1024];
367 ERROR ("nanosleep failed: %s",
368 sstrerror (errno, errbuf,
369 sizeof (errbuf)));
370 return (-1);
371 }
372 }
373 } /* while (loop == 0) */
375 DEBUG ("return (0);");
376 return (0);
377 } /* int do_loop */
379 static int do_shutdown (void)
380 {
381 plugin_shutdown_all ();
382 return (0);
383 } /* int do_shutdown */
385 #if COLLECT_DAEMON
386 static int pidfile_create (void)
387 {
388 FILE *fh;
389 const char *file = global_option_get ("PIDFile");
391 if ((fh = fopen (file, "w")) == NULL)
392 {
393 char errbuf[1024];
394 ERROR ("fopen (%s): %s", file,
395 sstrerror (errno, errbuf, sizeof (errbuf)));
396 return (1);
397 }
399 fprintf (fh, "%i\n", (int) getpid ());
400 fclose(fh);
402 return (0);
403 } /* static int pidfile_create (const char *file) */
405 static int pidfile_remove (void)
406 {
407 const char *file = global_option_get ("PIDFile");
409 DEBUG ("unlink (%s)", (file != NULL) ? file : "<null>");
410 return (unlink (file));
411 } /* static int pidfile_remove (const char *file) */
412 #endif /* COLLECT_DAEMON */
414 int main (int argc, char **argv)
415 {
416 struct sigaction sig_int_action;
417 struct sigaction sig_term_action;
418 struct sigaction sig_usr1_action;
419 struct sigaction sig_pipe_action;
420 char *configfile = CONFIGFILE;
421 int test_config = 0;
422 int test_readall = 0;
423 const char *basedir;
424 #if COLLECT_DAEMON
425 struct sigaction sig_chld_action;
426 pid_t pid;
427 int daemonize = 1;
428 #endif
429 int exit_status = 0;
431 /* read options */
432 while (1)
433 {
434 int c;
436 c = getopt (argc, argv, "htTC:"
437 #if COLLECT_DAEMON
438 "fP:"
439 #endif
440 );
442 if (c == -1)
443 break;
445 switch (c)
446 {
447 case 'C':
448 configfile = optarg;
449 break;
450 case 't':
451 test_config = 1;
452 break;
453 case 'T':
454 test_readall = 1;
455 global_option_set ("ReadThreads", "-1");
456 #if COLLECT_DAEMON
457 daemonize = 0;
458 #endif /* COLLECT_DAEMON */
459 break;
460 #if COLLECT_DAEMON
461 case 'P':
462 global_option_set ("PIDFile", optarg);
463 break;
464 case 'f':
465 daemonize = 0;
466 break;
467 #endif /* COLLECT_DAEMON */
468 case 'h':
469 exit_usage (0);
470 break;
471 default:
472 exit_usage (1);
473 } /* switch (c) */
474 } /* while (1) */
476 if (optind < argc)
477 exit_usage (1);
479 /*
480 * Read options from the config file, the environment and the command
481 * line (in that order, with later options overwriting previous ones in
482 * general).
483 * Also, this will automatically load modules.
484 */
485 if (cf_read (configfile))
486 {
487 fprintf (stderr, "Error: Reading the config file failed!\n"
488 "Read the syslog for details.\n");
489 return (1);
490 }
492 /*
493 * Change directory. We do this _after_ reading the config and loading
494 * modules to relative paths work as expected.
495 */
496 if ((basedir = global_option_get ("BaseDir")) == NULL)
497 {
498 fprintf (stderr, "Don't have a basedir to use. This should not happen. Ever.");
499 return (1);
500 }
501 else if (change_basedir (basedir))
502 {
503 fprintf (stderr, "Error: Unable to change to directory `%s'.\n", basedir);
504 return (1);
505 }
507 /*
508 * Set global variables or, if that failes, exit. We cannot run with
509 * them being uninitialized. If nothing is configured, then defaults
510 * are being used. So this means that the user has actually done
511 * something wrong.
512 */
513 if (init_global_variables () != 0)
514 return (1);
516 if (test_config)
517 return (0);
519 #if COLLECT_DAEMON
520 /*
521 * fork off child
522 */
523 memset (&sig_chld_action, '\0', sizeof (sig_chld_action));
524 sig_chld_action.sa_handler = SIG_IGN;
525 sigaction (SIGCHLD, &sig_chld_action, NULL);
527 if (daemonize)
528 {
529 if ((pid = fork ()) == -1)
530 {
531 /* error */
532 char errbuf[1024];
533 fprintf (stderr, "fork: %s",
534 sstrerror (errno, errbuf,
535 sizeof (errbuf)));
536 return (1);
537 }
538 else if (pid != 0)
539 {
540 /* parent */
541 /* printf ("Running (PID %i)\n", pid); */
542 return (0);
543 }
545 /* Detach from session */
546 setsid ();
548 /* Write pidfile */
549 if (pidfile_create ())
550 exit (2);
552 /* close standard descriptors */
553 close (2);
554 close (1);
555 close (0);
557 if (open ("/dev/null", O_RDWR) != 0)
558 {
559 ERROR ("Error: Could not connect `STDIN' to `/dev/null'");
560 return (1);
561 }
562 if (dup (0) != 1)
563 {
564 ERROR ("Error: Could not connect `STDOUT' to `/dev/null'");
565 return (1);
566 }
567 if (dup (0) != 2)
568 {
569 ERROR ("Error: Could not connect `STDERR' to `/dev/null'");
570 return (1);
571 }
572 } /* if (daemonize) */
573 #endif /* COLLECT_DAEMON */
575 memset (&sig_pipe_action, '\0', sizeof (sig_pipe_action));
576 sig_pipe_action.sa_handler = SIG_IGN;
577 sigaction (SIGPIPE, &sig_pipe_action, NULL);
579 /*
580 * install signal handlers
581 */
582 memset (&sig_int_action, '\0', sizeof (sig_int_action));
583 sig_int_action.sa_handler = sig_int_handler;
584 if (0 != sigaction (SIGINT, &sig_int_action, NULL)) {
585 char errbuf[1024];
586 ERROR ("Error: Failed to install a signal handler for signal INT: %s",
587 sstrerror (errno, errbuf, sizeof (errbuf)));
588 return (1);
589 }
591 memset (&sig_term_action, '\0', sizeof (sig_term_action));
592 sig_term_action.sa_handler = sig_term_handler;
593 if (0 != sigaction (SIGTERM, &sig_term_action, NULL)) {
594 char errbuf[1024];
595 ERROR ("Error: Failed to install a signal handler for signal TERM: %s",
596 sstrerror (errno, errbuf, sizeof (errbuf)));
597 return (1);
598 }
600 memset (&sig_usr1_action, '\0', sizeof (sig_usr1_action));
601 sig_usr1_action.sa_handler = sig_usr1_handler;
602 if (0 != sigaction (SIGUSR1, &sig_usr1_action, NULL)) {
603 char errbuf[1024];
604 ERROR ("Error: Failed to install a signal handler for signal USR1: %s",
605 sstrerror (errno, errbuf, sizeof (errbuf)));
606 return (1);
607 }
609 /*
610 * run the actual loops
611 */
612 do_init ();
614 if (test_readall)
615 {
616 if (plugin_read_all_once () != 0)
617 exit_status = 1;
618 }
619 else
620 {
621 INFO ("Initialization complete, entering read-loop.");
622 do_loop ();
623 }
625 /* close syslog */
626 INFO ("Exiting normally.");
628 do_shutdown ();
630 #if COLLECT_DAEMON
631 if (daemonize)
632 pidfile_remove ();
633 #endif /* COLLECT_DAEMON */
635 return (exit_status);
636 } /* int main */