1 /**
2 * collectd - src/collectd.c
3 * Copyright (C) 2005-2007 Florian octo Forster
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be included in
13 * all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21 * DEALINGS IN THE SOFTWARE.
22 *
23 * Authors:
24 * Florian octo Forster <octo at collectd.org>
25 * Alvaro Barcellos <alvaro.barcellos at gmail.com>
26 **/
28 #include "collectd.h"
29 #include "common.h"
31 #include "plugin.h"
32 #include "configfile.h"
34 #include <sys/types.h>
35 #include <sys/socket.h>
36 #include <sys/un.h>
37 #include <netdb.h>
39 #include <pthread.h>
41 #if HAVE_LOCALE_H
42 # include <locale.h>
43 #endif
45 #if HAVE_STATGRAB_H
46 # include <statgrab.h>
47 #endif
49 #ifndef COLLECTD_LOCALE
50 # define COLLECTD_LOCALE "C"
51 #endif
53 /*
54 * Global variables
55 */
56 char hostname_g[DATA_MAX_NAME_LEN];
57 cdtime_t interval_g;
58 int pidfile_from_cli = 0;
59 int timeout_g;
60 #if HAVE_LIBKSTAT
61 kstat_ctl_t *kc;
62 #endif /* HAVE_LIBKSTAT */
64 static int loop = 0;
66 static void *do_flush (void __attribute__((unused)) *arg)
67 {
68 INFO ("Flushing all data.");
69 plugin_flush (/* plugin = */ NULL,
70 /* timeout = */ 0,
71 /* ident = */ NULL);
72 INFO ("Finished flushing all data.");
73 pthread_exit (NULL);
74 return NULL;
75 }
77 static void sig_int_handler (int __attribute__((unused)) signal)
78 {
79 loop++;
80 }
82 static void sig_term_handler (int __attribute__((unused)) signal)
83 {
84 loop++;
85 }
87 static void sig_usr1_handler (int __attribute__((unused)) signal)
88 {
89 pthread_t thread;
90 pthread_attr_t attr;
92 /* flushing the data might take a while,
93 * so it should be done asynchronously */
94 pthread_attr_init (&attr);
95 pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
96 pthread_create (&thread, &attr, do_flush, NULL);
97 pthread_attr_destroy (&attr);
98 }
100 static int init_hostname (void)
101 {
102 const char *str;
104 struct addrinfo ai_hints;
105 struct addrinfo *ai_list;
106 struct addrinfo *ai_ptr;
107 int status;
109 str = global_option_get ("Hostname");
110 if (str != NULL)
111 {
112 sstrncpy (hostname_g, str, sizeof (hostname_g));
113 return (0);
114 }
116 if (gethostname (hostname_g, sizeof (hostname_g)) != 0)
117 {
118 fprintf (stderr, "`gethostname' failed and no "
119 "hostname was configured.\n");
120 return (-1);
121 }
123 str = global_option_get ("FQDNLookup");
124 if (IS_FALSE (str))
125 return (0);
127 memset (&ai_hints, '\0', sizeof (ai_hints));
128 ai_hints.ai_flags = AI_CANONNAME;
130 status = getaddrinfo (hostname_g, NULL, &ai_hints, &ai_list);
131 if (status != 0)
132 {
133 ERROR ("Looking up \"%s\" failed. You have set the "
134 "\"FQDNLookup\" option, but I cannot resolve "
135 "my hostname to a fully qualified domain "
136 "name. Please fix the network "
137 "configuration.", hostname_g);
138 return (-1);
139 }
141 for (ai_ptr = ai_list; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next)
142 {
143 if (ai_ptr->ai_canonname == NULL)
144 continue;
146 sstrncpy (hostname_g, ai_ptr->ai_canonname, sizeof (hostname_g));
147 break;
148 }
150 freeaddrinfo (ai_list);
151 return (0);
152 } /* int init_hostname */
154 static int init_global_variables (void)
155 {
156 char const *str;
158 interval_g = cf_get_default_interval ();
159 assert (interval_g > 0);
160 DEBUG ("interval_g = %.3f;", CDTIME_T_TO_DOUBLE (interval_g));
162 str = global_option_get ("Timeout");
163 if (str == NULL)
164 str = "2";
165 timeout_g = atoi (str);
166 if (timeout_g <= 1)
167 {
168 fprintf (stderr, "Cannot set the timeout to a correct value.\n"
169 "Please check your settings.\n");
170 return (-1);
171 }
172 DEBUG ("timeout_g = %i;", timeout_g);
174 if (init_hostname () != 0)
175 return (-1);
176 DEBUG ("hostname_g = %s;", hostname_g);
178 return (0);
179 } /* int init_global_variables */
181 static int change_basedir (const char *orig_dir)
182 {
183 char *dir;
184 size_t dirlen;
185 int status;
187 dir = strdup (orig_dir);
188 if (dir == NULL)
189 {
190 char errbuf[1024];
191 ERROR ("strdup failed: %s",
192 sstrerror (errno, errbuf, sizeof (errbuf)));
193 return (-1);
194 }
196 dirlen = strlen (dir);
197 while ((dirlen > 0) && (dir[dirlen - 1] == '/'))
198 dir[--dirlen] = '\0';
200 if (dirlen <= 0) {
201 free (dir);
202 return (-1);
203 }
205 status = chdir (dir);
206 if (status == 0)
207 {
208 free (dir);
209 return (0);
210 }
211 else if (errno != ENOENT)
212 {
213 char errbuf[1024];
214 ERROR ("change_basedir: chdir (%s): %s", dir,
215 sstrerror (errno, errbuf, sizeof (errbuf)));
216 free (dir);
217 return (-1);
218 }
220 status = mkdir (dir, S_IRWXU | S_IRWXG | S_IRWXO);
221 if (status != 0)
222 {
223 char errbuf[1024];
224 ERROR ("change_basedir: mkdir (%s): %s", dir,
225 sstrerror (errno, errbuf, sizeof (errbuf)));
226 free (dir);
227 return (-1);
228 }
230 status = chdir (dir);
231 if (status != 0)
232 {
233 char errbuf[1024];
234 ERROR ("change_basedir: chdir (%s): %s", dir,
235 sstrerror (errno, errbuf, sizeof (errbuf)));
236 free (dir);
237 return (-1);
238 }
240 free (dir);
241 return (0);
242 } /* static int change_basedir (char *dir) */
244 #if HAVE_LIBKSTAT
245 static void update_kstat (void)
246 {
247 if (kc == NULL)
248 {
249 if ((kc = kstat_open ()) == NULL)
250 ERROR ("Unable to open kstat control structure");
251 }
252 else
253 {
254 kid_t kid;
255 kid = kstat_chain_update (kc);
256 if (kid > 0)
257 {
258 INFO ("kstat chain has been updated");
259 plugin_init_all ();
260 }
261 else if (kid < 0)
262 ERROR ("kstat chain update failed");
263 /* else: everything works as expected */
264 }
266 return;
267 } /* static void update_kstat (void) */
268 #endif /* HAVE_LIBKSTAT */
270 /* TODO
271 * Remove all settings but `-f' and `-C'
272 */
273 static void exit_usage (int status)
274 {
275 printf ("Usage: "PACKAGE_NAME" [OPTIONS]\n\n"
277 "Available options:\n"
278 " General:\n"
279 " -C <file> Configuration file.\n"
280 " Default: "CONFIGFILE"\n"
281 " -t Test config and exit.\n"
282 " -T Test plugin read and exit.\n"
283 " -P <file> PID-file.\n"
284 " Default: "PIDFILE"\n"
285 #if COLLECT_DAEMON
286 " -f Don't fork to the background.\n"
287 #endif
288 " -h Display help (this message)\n"
289 "\nBuiltin defaults:\n"
290 " Config file "CONFIGFILE"\n"
291 " PID file "PIDFILE"\n"
292 " Plugin directory "PLUGINDIR"\n"
293 " Data directory "PKGLOCALSTATEDIR"\n"
294 "\n"PACKAGE_NAME" "PACKAGE_VERSION", http://collectd.org/\n"
295 "by Florian octo Forster <octo@collectd.org>\n"
296 "for contributions see `AUTHORS'\n");
297 exit (status);
298 } /* static void exit_usage (int status) */
300 static int do_init (void)
301 {
302 #if HAVE_SETLOCALE
303 if (setlocale (LC_NUMERIC, COLLECTD_LOCALE) == NULL)
304 WARNING ("setlocale (\"%s\") failed.", COLLECTD_LOCALE);
306 /* Update the environment, so that libraries that are calling
307 * setlocale(LC_NUMERIC, "") don't accidentally revert these changes. */
308 unsetenv ("LC_ALL");
309 setenv ("LC_NUMERIC", COLLECTD_LOCALE, /* overwrite = */ 1);
310 #endif
312 #if HAVE_LIBKSTAT
313 kc = NULL;
314 update_kstat ();
315 #endif
317 #if HAVE_LIBSTATGRAB
318 if (sg_init (
319 # if HAVE_LIBSTATGRAB_0_90
320 0
321 # endif
322 ))
323 {
324 ERROR ("sg_init: %s", sg_str_error (sg_get_error ()));
325 return (-1);
326 }
328 if (sg_drop_privileges ())
329 {
330 ERROR ("sg_drop_privileges: %s", sg_str_error (sg_get_error ()));
331 return (-1);
332 }
333 #endif
335 plugin_init_all ();
337 return (0);
338 } /* int do_init () */
341 static int do_loop (void)
342 {
343 cdtime_t interval = cf_get_default_interval ();
344 cdtime_t wait_until;
346 wait_until = cdtime () + interval;
348 while (loop == 0)
349 {
350 struct timespec ts_wait = { 0, 0 };
351 cdtime_t now;
353 #if HAVE_LIBKSTAT
354 update_kstat ();
355 #endif
357 /* Issue all plugins */
358 plugin_read_all ();
360 now = cdtime ();
361 if (now >= wait_until)
362 {
363 WARNING ("Not sleeping because the next interval is "
364 "%.3f seconds in the past!",
365 CDTIME_T_TO_DOUBLE (now - wait_until));
366 wait_until = now + interval;
367 continue;
368 }
370 CDTIME_T_TO_TIMESPEC (wait_until - now, &ts_wait);
371 wait_until = wait_until + interval;
373 while ((loop == 0) && (nanosleep (&ts_wait, &ts_wait) != 0))
374 {
375 if (errno != EINTR)
376 {
377 char errbuf[1024];
378 ERROR ("nanosleep failed: %s",
379 sstrerror (errno, errbuf,
380 sizeof (errbuf)));
381 return (-1);
382 }
383 }
384 } /* while (loop == 0) */
386 return (0);
387 } /* int do_loop */
389 static int do_shutdown (void)
390 {
391 plugin_shutdown_all ();
392 return (0);
393 } /* int do_shutdown */
395 #if COLLECT_DAEMON
396 static int pidfile_create (void)
397 {
398 FILE *fh;
399 const char *file = global_option_get ("PIDFile");
401 if ((fh = fopen (file, "w")) == NULL)
402 {
403 char errbuf[1024];
404 ERROR ("fopen (%s): %s", file,
405 sstrerror (errno, errbuf, sizeof (errbuf)));
406 return (1);
407 }
409 fprintf (fh, "%i\n", (int) getpid ());
410 fclose(fh);
412 return (0);
413 } /* static int pidfile_create (const char *file) */
415 static int pidfile_remove (void)
416 {
417 const char *file = global_option_get ("PIDFile");
418 if (file == NULL)
419 return 0;
421 return (unlink (file));
422 } /* static int pidfile_remove (const char *file) */
423 #endif /* COLLECT_DAEMON */
425 #ifdef KERNEL_LINUX
426 static int notify_upstart (void)
427 {
428 const char *upstart_job = getenv("UPSTART_JOB");
430 if (upstart_job == NULL)
431 return 0;
433 if (strcmp(upstart_job, "collectd") != 0)
434 return 0;
436 WARNING ("supervised by upstart, will stop to signal readyness");
437 raise(SIGSTOP);
438 unsetenv("UPSTART_JOB");
440 return 1;
441 }
443 static int notify_systemd (void)
444 {
445 int fd = -1;
446 const char *notifysocket = getenv("NOTIFY_SOCKET");
447 struct sockaddr_un su;
448 struct iovec iov;
449 struct msghdr hdr;
451 if (notifysocket == NULL)
452 return 0;
454 if ((strchr("@/", notifysocket[0])) == NULL ||
455 strlen(notifysocket) < 2)
456 return 0;
458 WARNING ("supervised by systemd, will signal readyness");
459 if ((fd = socket(AF_UNIX, SOCK_DGRAM, 0)) < 0) {
460 WARNING ("cannot contact systemd socket %s", notifysocket);
461 return 0;
462 }
464 bzero(&su, sizeof(su));
465 su.sun_family = AF_UNIX;
466 sstrncpy (su.sun_path, notifysocket, sizeof(su.sun_path));
468 if (notifysocket[0] == '@')
469 su.sun_path[0] = 0;
471 bzero(&iov, sizeof(iov));
472 iov.iov_base = "READY=1";
473 iov.iov_len = strlen("READY=1");
475 bzero(&hdr, sizeof(hdr));
476 hdr.msg_name = &su;
477 hdr.msg_namelen = offsetof(struct sockaddr_un, sun_path) +
478 strlen(notifysocket);
479 hdr.msg_iov = &iov;
480 hdr.msg_iovlen = 1;
482 unsetenv("NOTIFY_SOCKET");
483 if (sendmsg(fd, &hdr, MSG_NOSIGNAL) < 0) {
484 WARNING ("cannot send notification to systemd");
485 close(fd);
486 return 0;
487 }
488 close(fd);
489 return 1;
490 }
491 #endif /* KERNEL_LINUX */
493 int main (int argc, char **argv)
494 {
495 struct sigaction sig_int_action;
496 struct sigaction sig_term_action;
497 struct sigaction sig_usr1_action;
498 struct sigaction sig_pipe_action;
499 char *configfile = CONFIGFILE;
500 int test_config = 0;
501 int test_readall = 0;
502 const char *basedir;
503 #if COLLECT_DAEMON
504 struct sigaction sig_chld_action;
505 pid_t pid;
506 int daemonize = 1;
507 #endif
508 int exit_status = 0;
510 /* read options */
511 while (1)
512 {
513 int c;
515 c = getopt (argc, argv, "htTC:"
516 #if COLLECT_DAEMON
517 "fP:"
518 #endif
519 );
521 if (c == -1)
522 break;
524 switch (c)
525 {
526 case 'C':
527 configfile = optarg;
528 break;
529 case 't':
530 test_config = 1;
531 break;
532 case 'T':
533 test_readall = 1;
534 global_option_set ("ReadThreads", "-1");
535 #if COLLECT_DAEMON
536 daemonize = 0;
537 #endif /* COLLECT_DAEMON */
538 break;
539 #if COLLECT_DAEMON
540 case 'P':
541 global_option_set ("PIDFile", optarg);
542 pidfile_from_cli = 1;
543 break;
544 case 'f':
545 daemonize = 0;
546 break;
547 #endif /* COLLECT_DAEMON */
548 case 'h':
549 exit_usage (0);
550 break;
551 default:
552 exit_usage (1);
553 } /* switch (c) */
554 } /* while (1) */
556 if (optind < argc)
557 exit_usage (1);
559 plugin_init_ctx ();
561 /*
562 * Read options from the config file, the environment and the command
563 * line (in that order, with later options overwriting previous ones in
564 * general).
565 * Also, this will automatically load modules.
566 */
567 if (cf_read (configfile))
568 {
569 fprintf (stderr, "Error: Reading the config file failed!\n"
570 "Read the syslog for details.\n");
571 return (1);
572 }
574 /*
575 * Change directory. We do this _after_ reading the config and loading
576 * modules to relative paths work as expected.
577 */
578 if ((basedir = global_option_get ("BaseDir")) == NULL)
579 {
580 fprintf (stderr, "Don't have a basedir to use. This should not happen. Ever.");
581 return (1);
582 }
583 else if (change_basedir (basedir))
584 {
585 fprintf (stderr, "Error: Unable to change to directory `%s'.\n", basedir);
586 return (1);
587 }
589 /*
590 * Set global variables or, if that failes, exit. We cannot run with
591 * them being uninitialized. If nothing is configured, then defaults
592 * are being used. So this means that the user has actually done
593 * something wrong.
594 */
595 if (init_global_variables () != 0)
596 return (1);
598 if (test_config)
599 return (0);
601 #if COLLECT_DAEMON
602 /*
603 * fork off child
604 */
605 memset (&sig_chld_action, '\0', sizeof (sig_chld_action));
606 sig_chld_action.sa_handler = SIG_IGN;
607 sigaction (SIGCHLD, &sig_chld_action, NULL);
609 /*
610 * Only daemonize if we're not being supervised
611 * by upstart or systemd (when using Linux).
612 */
613 if (daemonize
614 #ifdef KERNEL_LINUX
615 && notify_upstart() == 0 && notify_systemd() == 0
616 #endif
617 )
618 {
619 if ((pid = fork ()) == -1)
620 {
621 /* error */
622 char errbuf[1024];
623 fprintf (stderr, "fork: %s",
624 sstrerror (errno, errbuf,
625 sizeof (errbuf)));
626 return (1);
627 }
628 else if (pid != 0)
629 {
630 /* parent */
631 /* printf ("Running (PID %i)\n", pid); */
632 return (0);
633 }
635 /* Detach from session */
636 setsid ();
638 /* Write pidfile */
639 if (pidfile_create ())
640 exit (2);
642 /* close standard descriptors */
643 close (2);
644 close (1);
645 close (0);
647 if (open ("/dev/null", O_RDWR) != 0)
648 {
649 ERROR ("Error: Could not connect `STDIN' to `/dev/null'");
650 return (1);
651 }
652 if (dup (0) != 1)
653 {
654 ERROR ("Error: Could not connect `STDOUT' to `/dev/null'");
655 return (1);
656 }
657 if (dup (0) != 2)
658 {
659 ERROR ("Error: Could not connect `STDERR' to `/dev/null'");
660 return (1);
661 }
662 } /* if (daemonize) */
663 #endif /* COLLECT_DAEMON */
665 memset (&sig_pipe_action, '\0', sizeof (sig_pipe_action));
666 sig_pipe_action.sa_handler = SIG_IGN;
667 sigaction (SIGPIPE, &sig_pipe_action, NULL);
669 /*
670 * install signal handlers
671 */
672 memset (&sig_int_action, '\0', sizeof (sig_int_action));
673 sig_int_action.sa_handler = sig_int_handler;
674 if (0 != sigaction (SIGINT, &sig_int_action, NULL)) {
675 char errbuf[1024];
676 ERROR ("Error: Failed to install a signal handler for signal INT: %s",
677 sstrerror (errno, errbuf, sizeof (errbuf)));
678 return (1);
679 }
681 memset (&sig_term_action, '\0', sizeof (sig_term_action));
682 sig_term_action.sa_handler = sig_term_handler;
683 if (0 != sigaction (SIGTERM, &sig_term_action, NULL)) {
684 char errbuf[1024];
685 ERROR ("Error: Failed to install a signal handler for signal TERM: %s",
686 sstrerror (errno, errbuf, sizeof (errbuf)));
687 return (1);
688 }
690 memset (&sig_usr1_action, '\0', sizeof (sig_usr1_action));
691 sig_usr1_action.sa_handler = sig_usr1_handler;
692 if (0 != sigaction (SIGUSR1, &sig_usr1_action, NULL)) {
693 char errbuf[1024];
694 ERROR ("Error: Failed to install a signal handler for signal USR1: %s",
695 sstrerror (errno, errbuf, sizeof (errbuf)));
696 return (1);
697 }
699 /*
700 * run the actual loops
701 */
702 do_init ();
704 if (test_readall)
705 {
706 if (plugin_read_all_once () != 0)
707 exit_status = 1;
708 }
709 else
710 {
711 INFO ("Initialization complete, entering read-loop.");
712 do_loop ();
713 }
715 /* close syslog */
716 INFO ("Exiting normally.");
718 do_shutdown ();
720 #if COLLECT_DAEMON
721 if (daemonize)
722 pidfile_remove ();
723 #endif /* COLLECT_DAEMON */
725 return (exit_status);
726 } /* int main */